tretinoin and Acute-Disease

The success of all-trans retinoic acid (ATRA) therapy for acute promyelocytic leukemia (APL) provides a rationale for using retinoic acid (RA)-based therapy for other subtypes of acute myeloid leukemia (AML). Recently, several studies showed that ATRA may drive leukemic cells efficiently into differentiation and/or apoptosis in a subset of AML patients with an NPM1 mutation, a FLT3-ITD, an IDH1 mutation, and patients overexpressing EVI-1. Because not all patients within these molecular subgroups respond to ATRA and clinical trials that tested ATRA response in non-APL AML patients have had disappointing results, the identification of additional biomarkers may help to identify patients who strongly respond to ATRA-based therapy. Searching for response biomarkers might also reveal novel RA-based combination therapies with an efficient differentiation/apoptosis-inducing effect in non-APL AML patients. Preliminary studies suggest that the epigenetic or transcriptional state of leukemia cells determines their susceptibility to ATRA. We hypothesize that reprogramming by inhibitors of epigenetic-modifying enzymes or by modulation of microRNA expression might sensitize non-APL AML cells for RA-based therapy. AML relapse is caused by a subpopulation of leukemia cells, named leukemic stem cells (LSCs), which are in a different epigenetic state than the total bulk of the AML. The survival of LSCs after therapy is the main cause of the poor prognosis of AML patients, and novel differentiation therapies should drive these LSCs into maturity. In this review, we summarize the current knowledge on the epigenetic aspects of susceptibility to RA-induced differentiation in APL and non-APL AML.

Topics: Acetylation; Acute Disease; Antineoplastic Agents; Apoptosis; Cell Differentiation; Gene Expression Regulation, Leukemic; Histones; Humans; Leukemia, Myeloid; MicroRNAs; Nucleophosmin; Tretinoin

To explore the characteristics and risk of etoposide-related leukemia in the treatment of hemophagocytic lymphohistiocytosis (HLH).. Clinical characteristics of a case with secondary acute promyelocytic leukemia (APL) were summarized and 10 cases of secondary leukemia after treatment for HLH from literature were analyzed.. The child was diagnosed with Epstein-Barr virus associated HLH and received HLH-2004 protocol. The cumulative dose of etoposide (VP16) was 3520 mg/m(2). The patient was diagnosed with APL after 28 months of HLH.He achieved complete remission after induction chemotherapy of all-trans-retinoic acid and darubicin. Consolidated chemotherapy was continued. There were 10 reports of etoposide-related leukemia after treatment for HLH in the literature.Review of 11 cases treated with VP16, of which cumulative doses were 900-20 500 mg/m(2). The interval period between HLH and secondary leukemia was 24 months. The types of secondary leukemia included 1 case with acute lymphoblastic leukemia, 1 case with myelodysplastic syndrome and 9 cases of acute myeloid leukemia. The abnormalities of chromosome included 3 patients with 11q23, 3 APL patients with t (15, 17).Seven patients survived and 4 died.. The latency period of etoposide-related leukemia is short. Acute myeloid leukemia and balanced chromosomal abnormality are common in etoposide-related leukemia. The risk factors for development of secondary leukemia are related to cumulative drug doses of etoposide, treatment schedules and co-administration of other antineoplastic agents.It is appropriate to keep suitable range of the cumulative dose of etoposide in HLH therapy in order to reduce the risk of therapy related leukemia.

Topics: Acute Disease; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Child, Preschool; Daunorubicin; Epstein-Barr Virus Infections; Etoposide; Humans; Leukemia, Promyelocytic, Acute; Lymphohistiocytosis, Hemophagocytic; Male; Neoplasms, Second Primary; Risk Assessment; Treatment Outcome; Tretinoin

Transcription factors play essential roles in controlling normal blood development and their alteration leads to abnormalities in cell proliferation, differentiation and survival. In many childhood acute leukemias, transcription factors are altered through chromosomal translocations that change their functional properties resulting in repressed activity or inappropriate activation. The development of therapies that specifically target these molecular abnormalities holds promise for improving the outcome in diseases that remain challenging to treat, such as childhood T-cell acute lymphoblastic leukemia and acute myeloid leukemia, with improved toxicity profiles. All trans-retinoic acid and arsenic trioxide have already demonstrated efficacy in acute promyelocytic leukemia in both adults and children. Newer agents, such as histone deacetylase inhibitors, drugs targeting the NOTCH pathway, and short interfering RNAs have shown encouraging results in pre-clinical studies and are likely to enter the clinical arena in the near future. Through an improved understanding of the pathways and mechanisms underlying the malignant transformation induced by altered transcription factors, new targeted therapies will be designed that should greatly enhance current available treatments.

Topics: Acute Disease; Antineoplastic Agents; Arsenic Trioxide; Arsenicals; Child; DNA Methylation; Drug Delivery Systems; Histone Deacetylase Inhibitors; Humans; Leukemia; Oxides; Transcription Factors; Tretinoin

Valproic acid (VPA) has been used as an anticonvulsant for decades. Recently, it was demonstrated that VPA also acts as a histone deacetylase inhibitor and induces differentiation and apoptosis in a variety of malignant cells in vitro. The effect of VPA on tumor cells differs according to cell type, degree of differentiation, and underlying genetic alterations. Clinical trials with VPA have focused on acute myeloid leukemia and the myelodysplastic syndromes. When it was used as monotherapy or in combination with all-trans retinoic acid, which synergizes in vitro, VPA achieved hematologic improvement in a subset of patients. Similar to other inhibitors of histone deacetylases, complete or partial remissions rarely were observed. In this report, the authors reviewed the in vitro and in vivo data obtained with VPA, and they considered possible combination regimens aimed at improving therapeutic efficacy.

Topics: Acute Disease; Apoptosis; Cell Line, Tumor; Drug Synergism; Drug Therapy, Combination; Histone Deacetylase Inhibitors; Humans; Leukemia, Myeloid; Tretinoin; Valproic Acid

The beginning of this century was marked, in our specialty as in other, by two revolutions: the routine use of molecular biology tools for a better prognosis of the disease (flt3 receptor duplication in AML, mutational profile of Ig genes in CLL, gene expression profile with ARN chips in aggressive lymphomas.), and the discovery of "intelligent" molecules, targeting the tumoral cell. In this category, the most appealing is the STI571 (Gleevec , Novartis), targeting the molecular abnormality of the cells expressing bcr-abl protein: CML, ALL Ph1(+). Other molecules targeting signal transduction proteins (ras farnesylation inhibitors for example) are already in clinical trials. The increasing therapeutic use of monoclonal antibodies is also to be cited, with a special mention concerning the rituximab, used in several B lymphoid pathologies, from lymphoma to autoimmune diseases. His very good tolerance permits his use in ambulatory patients, and his combination with chemotherapy or his linkage with radioactive elements render this molecule indispensable. The other side of these molecules is their incredibly high cost, explaining the uncontrolled expenses in 2001 of hospitals hosting hematology as well as oncology activities.

Topics: Acute Disease; Antineoplastic Combined Chemotherapy Protocols; Benzamides; Hematopoietic Stem Cell Transplantation; Humans; Imatinib Mesylate; Immunotoxins; Leukemia, Lymphoid; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Leukemia, Myeloid; Lymphoma; Myelodysplastic Syndromes; Piperazines; Pyrimidines; Tretinoin

Therapy-related MDS and AML are complications of intensive chemotherapy regimens. Traditionally, patients exposed to topoisomerase II inhibitors are reported to develop secondary AML with abnormalities of chromosome 11q23. We evaluated the long-term hematologic toxicity of topoisomerase II-intensive high-dose mitoxantrone-based chemotherapy in 163 newly diagnosed acute leukemia patients treated over an 8 year period. Nine (5.5%) patients developed new cytogenetic abnormalities. Four patients developed MDS with progression to AML, three patients developed new abnormalities at the time of relapse, and three patients (including one of the former patients) had changes that were not associated with hematologic disease. The abnormalities most frequently involved chromosomes 7q, 20q, 1q, and 13q. Despite the use of topoisomerase II-intensive treatment, no patient developed an abnormality involving chromosome 11q23. Spontaneous resolution of some changes and prolonged persistence of others in the absence of hematologic disease indicates that some cytogenetic changes are not sufficient to promote leukemogenesis.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Chromosome Aberrations; Chromosomes, Human, Pair 11; Clinical Trials, Phase II as Topic; Clinical Trials, Phase III as Topic; Cytarabine; Disease Progression; Disease-Free Survival; Enzyme Inhibitors; Etoposide; Female; Humans; Idarubicin; Incidence; Karyotyping; Leukemia, Myeloid; Life Tables; Male; Middle Aged; Mitoxantrone; Myelodysplastic Syndromes; Neoplasm Proteins; Neoplasms, Second Primary; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Randomized Controlled Trials as Topic; Remission Induction; Retrospective Studies; Topoisomerase II Inhibitors; Treatment Outcome; Tretinoin

Recent discoveries have identified key molecular events in the pathogenesis of acute promyelocytic leukemia (APL), caused by chromosomal rearrangements of the transcription factor RAR (resulting in a fusion protein with the product of other cellular genes, such as PML). Oligomerization of RAR, through a self-association domain present in PML, imposes an altered interaction with transcriptional co-regulators (NCoR/SMRT). NCoR/SMRT are responsible for recruitment of histone deacetylases (HDACs), which is required for transcriptional repression of PML-RAR target genes, and for the transforming potential of the fusion protein. Oligomerization and altered recruitment of HDACs are also responsible for transformation by the fusion protein AML1-ETO, extending these mechanisms to other forms of acute myeloid leukemias (AMLs) and suggesting that HDAC is a common target for myeloid leukemias. Strikingly, AML1-ETO expression blocks retinoic acid (RA) signaling in hematopoietic cells, suggesting that interference with the RA pathway (genetically altered in APL) by HDAC recruitment may be a common theme in AMLs. Treatment of APLs with RA, and of other AMLs with RA plus HDAC inhibitors (HDACi), results in myeloid differentiation. Thus, activation of the RA signaling pathway and inhibition of HDAC activity might represent a general strategy for the differentiation treatment of myeloid leukemias.

Topics: Acute Disease; Animals; Cell Differentiation; Enzyme Inhibitors; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Tretinoin

Successful treatment of acute promyelocytic leukemia (APL) has identified several novel approaches to induce leukemic cell differentiation and selective apoptosis by overcoming the site-specific transcriptional repression by dominant fusion leukemogenic proteins characteristic of APL and other forms of acute myelogenous leukemia (AML). These therapeutic approaches include the use of site-specific ligands, receptors and cytokines, disruption of dominant fusion leukemogenic proteins, chromatin remodeling and combining the above with cytotoxic chemotherapy. With the exception of cytotoxic chemotherapy, the above therapeutic strategies do not significantly affect normal hematopoiesis and their combinations have been shown to be synergistic in inducing myeloid differentiation and apoptosis in several AML cell lines and in patients with APL. These approaches are, in general, non-cross resistant and should be well tolerated particularly in elderly patients with AML. Clinical studies which include biologic end points for differentiation induction, histone acetylation and selective apoptosis are presently in development to evaluate these strategies in the treatment of AML.

Topics: Acute Disease; Adult; Aged; Animals; Antineoplastic Agents; Apoptosis; Butyrates; Cell Differentiation; Cholecalciferol; Chromatin; Drug Design; Drug Synergism; Gene Expression Regulation, Leukemic; Granulocyte Colony-Stimulating Factor; Humans; Leukemia, Myeloid; Ligands; Mice; Middle Aged; Oncogene Proteins, Fusion; Phenylbutyrates; Transcription, Genetic; Translocation, Genetic; Tretinoin

This review briefly summarizes literature noteworthy in the field of adult acute leukemia published during 1999. The relationship between specific cytogenetic abnormalities and response to treatment was explored within a clinical framework. In particular, detailed analyses of the abnormalities seen in acute promyelocytic leukemia were examined. Two case reports of special interest were published: one shed light on the role of histone deacetylase inhibitors in combination with all-trans retinoic acid, and the other, on the role of granulocyte colony-stimulating factor in this disease. The clinical activity of arsenic was also reported and its mechanism of action explored. In acute lymphoblastic leukemia, attention was focused on occult translocations, and the importance of minimal residual disease was again emphasized. Lastly, results of early clinical trials using an anti-CD19 antibody were reported, with provocative results.

Topics: Acute Disease; Adolescent; Adult; Antibodies, Monoclonal; Antigens, CD19; Antineoplastic Combined Chemotherapy Protocols; Bone Marrow Transplantation; Child; Chromosome Aberrations; Clinical Trials as Topic; Combined Modality Therapy; DNA, Neoplasm; Drug Design; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Humans; Infant; Leukemia; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Middle Aged; Multicenter Studies as Topic; Neoplasm Proteins; Neoplasm, Residual; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Prognosis; Randomized Controlled Trials as Topic; Treatment Outcome; Tretinoin

The outlook for patients with acute promyelocytic leukaemia has improved vastly with the use of all-trans retinoic acid. The development of this therapeutic agent stemmed from the finding that an abnormality of the retinoic acid receptor is involved in this disease. In the search for other molecular abnormalities in the acute leukaemias that might serve as therapeutic targets, the chromosomal translocations associated with this group of disorders have been helpful in indicating where to look for potential cancer genes. Some common signal-transduction pathways through which different such genes act have been identified, and compounds that interfere with these pathways are already being screened for.

Topics: Acute Disease; Chronic Disease; Humans; Leukemia; Leukemia, Promyelocytic, Acute; Molecular Biology; Protein-Tyrosine Kinases; Translocation, Genetic; Tretinoin

The bcl-2 gene encodes a mitochondrial protein that inhibits the onset of apoptosis induced by growth factor withdrawal or cytotoxic agents. Using quantitative flow cytometry and expressing bcl-2 levels as the number of molecules of equivalent soluble fluorochrome (MESF) per cell, we have shown that bcl-2 protein expression in the blast cells from patients with acute myeloblastic leukaemia (AML) is heterogeneous, but not related to FAB type. The blast cells from AML patients with the capacity to grow and survive autonomously in vitro were found to have higher bcl-2 MESF values than those that were dependent upon exogenous growth factors. We have previously reported that the blast cells from 70% of AML patients exhibit autonomous growth and autocrine growth factor production in vitro and that this has been shown to be an important indicator of poor prognosis in AML. High bcl-2 expression has also been associated with a low complete remission rate and poor survival in AML. In the patients whose blast cells exhibited autonomous growth, neutralisation of endogenous GM-CSF resulted in down-regulation of bcl-2 protein, whereas in blast cells from patients whose cells proliferated only in the presence of added growth factors, incorporation of recombinant human (rh) GM-CSF in the culture media resulted in up-regulation of bcl-2. Because CD34 positivity has been reported as another indicator of poor prognosis in AML, we compared bcl-2 expression in cases of CD34 positive AML, CD34 negative AML and CD34 positive normal bone marrow cells. Bcl-2 was found to be strongly expressed on the CD34+ normal bone marrow cells. The blast cells from CD34+ AML patients expressed significantly higher bcl-2 levels than CD34- AML patients. In five cases of CD34+ AML, the bcl-2 levels were determined on purified CD34+ and CD34- blast cell populations. The CD34+ blast cells were found to express significantly higher bcl-2 levels compared with the CD34-blast cells. Our data would suggest that quantification of bcl-2 in AML blast cell may be useful as a prognostic indicator in AML.

Topics: Acute Disease; Adult; Antigens, CD34; Antigens, Neoplasm; Antineoplastic Agents; Apoptosis; Cell Division; Drug Resistance, Neoplasm; Granulocyte-Macrophage Colony-Stimulating Factor; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid; Neoplasm Proteins; Neoplastic Stem Cells; Prognosis; Proto-Oncogene Proteins c-bcl-2; Tretinoin; Tumor Cells, Cultured

Differentiating therapy is a new antineoplastic strategy which has received increasing attention due to the remarkable activity of the vitamin A derivative, all-trans retinoic acid (ATRA) in patients with acute promyelocytic leukemia (APL). Although it has been known for years that a variety of agents, including retinoids, could induce leukemic cells to differentiate in vitro, it was not until the initial report from Shanghai in 1988 that laboratory studies translated into clinical activity and benefit in patients. Since this initial report, a number of studies have confirmed that the majority of patients with both newly diagnosed and previously chemotherapy-treated patients with APL achieve complete remission (CR) with ATRA. In addition, the characteristic life-threatening coagulopathy resolves quickly. Several limitations to this approach have emerged, including the development of retinoid resistance, hyperleukocytosis and the retinoic acid syndrome, a constellation of findings including unexplained fever, fluid retention, pleuropericardial effusions and pulmonary infiltrates. Although ATRA is very effective in inducing CR, its benefits compared to conventional chemotherapy are only now being addressed. The first prospective randomized trial comparing ATRA plus chemotherapy to chemotherapy alone was terminated early because of an improved event-free survival for patients receiving ATRA. The benefit was attributable to a difference in relapse rate. A large, intergroup, prospective, randomized trial comparing conventional chemotherapy to ATRA for induction and ATRA to observation for maintenance has recently completed accrual and will provide insight into the emerging role of ATRA in patients with APL. ATRA represents the first example of a specific form of antileukemic therapy targeting a specific genetic abnormality and may serve as a paradigm for the development of differentiating therapy for patients with other hematologic malignancies.

Topics: Acute Disease; Cell Differentiation; Clinical Protocols; Clinical Trials, Phase II as Topic; Humans; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Randomized Controlled Trials as Topic; Translocation, Genetic; Tretinoin

A review of recent information on the expression and the ATRA-driven modulation of cell surface adhesion molecules of acute myelogenous leukemia blast cells is presented. Cytofluorometric studies on fresh blast cells have demonstrated that CD11a, CD11b CD11c, CD15, CD45RO and CD54 expression is significantly lower in acute promyelocytic leukemia (APL) than is acute myeloid leukemia of other subtypes (AML). In vitro treatment with ATRA dramatically modifies the adhesion phenotype of APL blast cells, promoting a consistently striking up-regulation of CD11b, CD11c, CD15, CD65, CD54, and CD38. Which is in general, poorly demonstrable in AML. The behaviour of CD15s is variable and fully independent from CD15 and CD65 in induction experiments, suggesting a differential enzyme regulation within the selectin ligand system. ATRA is capable, in both APL and AML, of producing a switch from the high- (RA) to the low- (RO) molecular weight isoform of CD54, Moreover, treatment with this retinoid exerts a negative regulation of the membrane expression of CD49e, CD58 and CD11a in APL as well as in AML. Of particular interest is the fact that the negative effect on CD1 1a expression generates an asynchronous phenotype in APL (CD11a-, CD11b+, CD15+), undetectable on normal maturing myeloid cells. In the last part of this review the possible implications of adhesion molecule modulation in the pathogenesis of ATRA syndrome are discussed.

Topics: Acute Disease; Cell Adhesion Molecules; Humans; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Tretinoin

Given the many ways our culture promotes deeply tanned skin as a symbol of beauty, health, and even happiness, physicians face an uphill battle in promoting the healthy aspects of a pale complexion. Not only can excessive solar exposure accelerate and intensify aging in skin, it can also lead to serious health risks. Drs Browder and Beers tell why photoaging happens and how to prevent it.

Topics: Acute Disease; Biopsy; Chronic Disease; Family Practice; Humans; Patient Education as Topic; Protective Clothing; Skin Aging; Sunscreening Agents; Tretinoin; Ultraviolet Rays

Topics: Acute Disease; Antineoplastic Combined Chemotherapy Protocols; Carboplatin; Cytarabine; Daunorubicin; Drug Evaluation; Etoposide; Humans; Idarubicin; Leukemia, Myeloid; Middle Aged; Mitoxantrone; Remission Induction; Tretinoin

The use of chemical agents that induce differentiation of malignant cells to normal cells has held great promise as an adjunct to standard chemotherapy. In vitro data has shown that 13-cis-retinoic acid can differentiate certain leukemia cell lines (e.g., HL-60) into stable granulocyte cells. In this study, oral 13-cis-retinoic acid was administered to four patients with the myelodysplastic syndrome (MDS) and to four patients with acute nonlymphocytic leukemia (ANLL). None of the MDS patients showed an hematologic response to the drug, while three of four ANLL patients responded with normalized peripheral blood counts. The side effects of the drug at 80-120 mg/d (dry skin, cheilitis, epistaxis) were self limiting.

Topics: Acute Disease; Cell Differentiation; Hemoglobins; Humans; Isotretinoin; Leukemia; Middle Aged; Myelodysplastic Syndromes; Tretinoin

Major advances have been made in the past 10 yr in both the understanding of the biologic characteristics of acute nonlymphocytic leukemia and in the treatment of patients with this disease. Advances in the biologic characteristics include: a better understanding of the nature of leukemic cell proliferation and differentiation; a clearer description of the morphological, histochemical, and ultrastructural characteristics of leukemic cells; a recognition that a high percentage of patients may have specific cytogenetic abnormalities; and a recognition that biochemical differences exist between acute nonlymphocytic leukemia (ANLL) and acute lymphoblastic leukemia (ALL). Today, over 70% of children with ANLL can be induced into a complete remission and over 25% are remaining in a continuous remission for over 2 yr. In spite of these improved results, the best method of extending remissions is unknown. It is unlikely that better results of therapy will be achieved in the future by tailoring the treatment according to the biologic characteristics of the patient, since it appears that ANLL is a heterogeneous group of diseases.

Topics: Acute Disease; Adolescent; Adult; Aged; Bone Marrow Transplantation; Brain Diseases; Cell Aggregation; Cell Differentiation; Cytogenetics; Down Syndrome; Doxorubicin; Granulocytes; Hematopoietic Stem Cells; Humans; Injections, Spinal; Kinetics; Leukemia; Leukocyte Count; Macrophages; Methotrexate; Middle Aged; Mitosis; Phagocytosis; Prognosis; Receptors, Drug; Tretinoin

Various methods of intensive chemotherapy have contributed to an improved survival in pediatric acute myeloid leukemia (AML). We here report the long-term results of the two consecutive trials of Tokyo Children's Cancer Study Group (TCCSG), incorporating repetitive use of high-dose cytarabine (HD-Ara-C) based combination chemotherapy in post-remission phase.. A total of 216 eligible children with newly diagnosed AML were treated in the two consecutive multi-center trials of TCCSG, M91-13 and M96-14, from August 1991 to September 1998. In M91-13 trial, patients received eight courses of intensive post-remission chemotherapy, including six HD-Ara-C containing courses, after remission-induction therapy. Autologous hematopoietic stem cell transplantation (HSCT) could be selected by physician's choice, and allogeneic HSCT was allocated if donor was available. In M96-14 trial, the last two HD-Ara-C courses were omitted from the chemotherapy arm.. The remission-induction rate was 88.8% and probability of 5-year Overall survival (OS) and event-free survival (EFS) were 62% (56-69% with 95% Confidence intervals (CIs)) and 56% (49-62%), respectively. Treatment-related mortality (TRM) was 7.8%. Among patients without Down syndrome (DS) or acute promyelocytic leukemia (APL), the presence of t(8;21) or inv(16) was a significant good prognostic factor both in the univariate and multivariate analyses. Children with DS (N = 10) and APL (N = 14) also showed a good survival exceeding 70% in 5 years.. These results suggest that repetitive use of HD-Ara-C was effective and safe for childhood AML. However, further optimization of AML therapy is required.

Topics: Acute Disease; Adolescent; Antimetabolites, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Child; Child, Preschool; Combined Modality Therapy; Cytarabine; Disease-Free Survival; Down Syndrome; Doxorubicin; Drug Administration Schedule; Etoposide; Female; Hematopoietic Stem Cell Transplantation; Humans; Hydrocortisone; Infant; Infections; Japan; Kaplan-Meier Estimate; Leukemia, Myeloid; Male; Methotrexate; Mitoxantrone; Remission Induction; Survival Analysis; Transplantation, Autologous; Transplantation, Homologous; Treatment Outcome; Tretinoin; Vincristine

The survival of older patients with acute myeloid leukemia has not improved. Few clinical trials have been available for older patients who are not considered fit for an intensive chemotherapy approach.. Between December 1998 and November 2003, as part of National Cancer Research Institute Acute Myeloid Leukemia 14 Trial, 217 patients, who were deemed unfit for intensive chemotherapy were randomized to receive low-dose cytarabine (Ara-C) (20 mg twice daily for 10 days) or hydroxyurea with or without all-trans retinoic acid (ATRA).. Low-dose ara-C produced a better remission rate (18% vs 1%; odds ratio [OR], 0.15; 95% confidence interval [95% CI], 0.06-0.37; P = .00006) and better overall survival (OR, 0.60; 95% CI, 0.44-0.81; P = .0009), which was accounted for by the achievement of complete remission (CR) (duration of CR: 80 weeks vs 10 weeks for patients with no CR). Patients who had adverse cytogenetics did not benefit. ATRA had no effect. Toxicity scores or supportive care requirements did not differ between the treatment arms.. Older, less fit patients have a poor outcome, and few trials have been conducted in this patient group. Low-dose ara-C treatment was superior to best supportive care and hydroxyurea because it had greater success in achieving CR, and it could represent standard care against which new treatments may be compared in this patient group.

Topics: Acute Disease; Aged; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Female; Humans; Hydroxyurea; Leukemia, Myeloid; Male; Middle Aged; Myelodysplastic Syndromes; Risk; Survival; Treatment Outcome; Tretinoin

Valproic acid (VPA) inhibits histone deacetylase activity and, synergizing with all-trans retinoic acid (ATRA), achieves differentiation induction of myeloid blast cells in vitro.. We used VPA in 58 patients with acute myeloid leukemia (AML) who were too old and/or medically unfit to receive intensive chemotherapy (32 AML secondary to myelodysplastic syndrome [MDS], 22 de novo AML, 4 AML secondary to myeloproliferative syndrome). VPA serum concentrations were 50-100 mug/mL. Thirty-one patients received VPA monotherapy. ATRA was added later in 13 patients who did not respond or who relapsed. Another 27 patients received VPA plus ATRA from the start. Median treatment duration was 93 days for VPA and 88 days for ATRA.. The response rate was only 5% according to International Working Group (IWG) criteria for AML but was 16% when IWG response criteria for MDS were used, which capture hematologic improvement and stabilization of the disease. These endpoints, which are not necessarily correlated with diminishing blast counts, are relevant for the patients' quality of life. Among 23 patients with a peripheral blast count > 5%, 6 (26%) showed a diminishing blast count, and 5 of these had a complete peripheral blast clearance.. Future trials should combine VPA with chemotherapy or demethylating agents.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Female; Histone Deacetylase Inhibitors; Humans; Leukemia, Myeloid; Male; Middle Aged; Treatment Outcome; Tretinoin; Valproic Acid

Topics: Acute Disease; Administration, Oral; Aged; Antineoplastic Combined Chemotherapy Protocols; Drug Administration Schedule; Etoposide; Female; Humans; Idarubicin; Injections, Intravenous; Leukemia, Myeloid; Male; Middle Aged; Recurrence; Remission Induction; Survival Rate; Treatment Outcome; Tretinoin

The authors investigated the efficacy and safety of the histone deacetylase inhibitors valproic acid (VPA) and all-trans retinoic acid (ATRA) as differentiation agents in a cohort of older, poor-risk patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS).. Twenty older patients with recurrent or refractory AML or MDS were treated in a Phase II protocol with sequential VPA and ATRA therapy. VPA was started at a dose of 10 mg/kg per day and then escalated to achieve the serum concentration of 45-100 microg/mL. ATRA was added at 45 mg/square meters (sm) per day when VPA reached the target serum concentration. Only patients treated continuously for > or = 2 months were considered evaluable.. Hematologic improvement, according to World Health Organization criteria, was observed in 6 of 20 patients enrolled in the protocol but in 6 of 11 considered evaluable. In five patients, a major platelet response was observed, achieving platelet transfusion independence. Three of these five patients also exhibited a minor erythroid response. A sixth patient showed both a minor erythroid response and a platelet response. The median duration of response was 189 days (range, 63-550 days). No significant reduction in the blast count was observed. Grade 3 neurocortical toxicity was observed in four patients. Severe bone pain was experienced by 4 patients (2 Grade 4 and 2 Grade 3) and was associated with an increase in the peripheral blast cell count. Treatment with ATRA did not modify the response observed with VPA alone.. Differentiation therapy with VPA was of clinical benefit in approximately 30% of elderly patients with AML and MDS of the refractory anemia with excess of blast type with unfavorable prognostic features. A striking platelet transfusion independence lasting several months may be obtained in some patients, reducing the burden of palliative care and improving the quality of life.

Topics: Acute Disease; Aged; Female; Humans; Leukemia, Myeloid; Male; Middle Aged; Myelodysplastic Syndromes; Platelet Count; Risk; Tretinoin; Valproic Acid

Valproic acid (VPA) inhibits histone deacetylase activity and induces differentiation of acute myeloid leukemia (AML) blasts in vitro. We observed clinical responses to VPA in patients with myelodysplastic syndrome (MDS) and AML. Here, we report follow-up data on 75 patients. Of these, 66 were started on VPA monotherapy, with later addition of all-trans retinoic acid (ATRA) in patients who did not respond or relapsed. Nine patients were treated with VPA + ATRA from the start. Median treatment duration was 4 months for VPA and 2 months for ATRA. Hematological improvement, according to international working group criteria for MDS, was observed in 18 patients (24%). Median response duration was 4 months. ATRA exerted no additional effect in patients receiving the combination from the start or benefited primary VPA nonresponders. However, of ten VPA responders who relapsed, four achieved a second response after addition of ATRA. Response rates were strongly dependent on disease type according to WHO classification. We found a response rate of 52% in MDS patients with a normal blast count (refractory sideroblastic anemia, refractory cytopenia with multilineage dysplasia, and refractory sideroblastic cytopenia with multilineage dysplasia). The response rate was 6% in refractory anemia with excess blasts (I + II), 16% in AML, and 0% in chronic myelomonocytic leukemia. Bone marrow blast count was the only variable that predicted responses. We conclude that VPA is clinically useful in low-risk MDS. For patients with high-risk MDS, VPA may be combined with chemotherapy or demethylating drugs. If patients relapse after an initial response to VPA, ATRA has the potential to induce a prolonged second response.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Cell Differentiation; Female; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Kaplan-Meier Estimate; Leukemia, Myeloid; Male; Middle Aged; Myelodysplastic Syndromes; Remission Induction; Treatment Outcome; Tretinoin; Valproic Acid

Topics: Acute Disease; Antineoplastic Combined Chemotherapy Protocols; Clinical Trials as Topic; Humans; Leukemia, Myeloid; Prognosis; Transplantation, Homologous; Tretinoin

The purpose of our study was (i) to evaluate the impact of all-trans retinoic acid (ATRA) given as adjunct to chemotherapy and (ii) to compare second consolidation vs maintenance therapy in elderly patients with acute myeloid leukemia (AML). A total of 242 patients aged >or=61 years (median, 66.6 years) with AML were randomly assigned to ATRA beginning on day +3 after the initiation of chemotherapy (ATRA-arm, n=122) or no ATRA (standard-arm, n=120) in combination with induction and first consolidation therapy. A total of 61 patients in complete remission (CR) were randomly assigned to second intense consolidation (n=31) or 1-year oral maintenance therapy (n=30). After induction therapy the intention-to-treat analysis revealed a significant difference in CR rates between the ATRA- and the standard-arm (52 vs 39%; P=0.05). Event-free (EFS) and overall survival (OS) were significantly better in the ATRA-compared to the standard-arm (P=0.03 and 0.01, respectively). OS after second randomization was significantly better for patients assigned to intensive consolidation therapy (P<0.001). The multivariate model for survival revealed lactate dehydrogenase, cytogenetic risk group, age, and first and second randomization as prognostic variables. In conclusion, the addition of ATRA to induction and consolidation therapy may improve CR rate, EFS and OS in elderly patients with AML.

Topics: Acute Disease; Aged; Aged, 80 and over; Anemia, Refractory, with Excess of Blasts; Antineoplastic Combined Chemotherapy Protocols; Combined Modality Therapy; Cytarabine; Etoposide; Humans; Idarubicin; Leukemia, Myeloid; Middle Aged; Prognosis; Remission Induction; Survival Rate; Transplantation, Homologous; Tretinoin

All trans retinoic acid has shown a remarkable effectiveness in acute promyelocytic leukemia. These results have encouraged studies of treatment with ATRA in other acute myeloid leukemia subtypes.. In order to evaluate toxicity and antileukemic efficacy of all ATRA in patients with relapsed or refractory non promyelocytic AML, 95 patients (median age, 58 years; range, 20 to 80 years), with unclassified AML according to the FAB classification or secondary AML at diagnosis, or refractory or relapsing AML, received induction therapy with Idarubicin, 10 mg/m(2)/day, for 3 days and cytarabine, 1000 mg/m(2)/12 h, for 6 days, alone or combined, on a randomized basis, with ATRA, 45 mg/m(2)/day, from day 1 to complete remission. Patients in CR received maintenance therapy with 6 monthly courses combining Ida, 10 mg/m(2)/day, intravenously, on day 1 with Ara-C100 mg/m(2)/day, subcutaneously, from day 1 to day 5.. Results were evaluated after one induction course. Overall 54 patients (57%, 26 with ATRA and 28 without ATRA) achieved CR including five patients treated at time of initial diagnosis, seven previously resistant, 38 in first relapse and four in further relapse. Thirty patients (31%) had resistant disease and 11 (12%) died from toxicity. Median time for neutrophil recovery to 0.5 x 10(9)/l and platelets to 20 x 10(9)/l was 31 and 21 days respectively. Severe toxicity (WHO grade >or=3) included infections (37%), diarrhea (9%), bleeding (3%), vomiting (16%), hyperbilirubinemia (5%), mucositis (6%) and hypercreatininemia (2%). No ATRA syndrome was noted in the ATRA arm. Median overall survival for the entire cohort was 6.3 months and median disease-free survival was 4.7 months. There were no statistical differences in terms of CR, DFS, and OS between the two arms.. We conclude that ATRA in combination with Ida and Ara-C can be administered safely to high-risk AML patients. However, in this setting, ATRA did not offer any advantage when compared to chemotherapy alone.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Female; Humans; Idarubicin; Leukemia, Myeloid; Male; Middle Aged; Remission Induction; Salvage Therapy; Survival Analysis; Therapeutic Equivalency; Treatment Outcome; Tretinoin

To evaluate the efficiency of combination of interferon-alpha (INF) and all trans-retinoic acid (ATRA) as a treatment for maintaining remission in high risk group patients with acute myeloid leukemia (AML).. Three-day INF + ATRA course was administered every 3 months to 22 patients with AML from high risk group (impossibility of drug therapy during the first complete remission, resistant forms of AML, relapses, secondary AML, acute promyelocytic leukemia after attaining molecular remission).. INF + ATRA during remission maintained a long first complete remission (median 18 months) in patients with primary AML after small-volume drug therapy, led to long first and second complete remissions (median 12 months) in patients with resistant AML, and induced and maintained molecular remissions in patients with acute promyelocytic leukemia.

Topics: Acute Disease; Adolescent; Adult; Antineoplastic Combined Chemotherapy Protocols; Drug Therapy, Combination; Female; Humans; Interferon-alpha; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Male; Middle Aged; Recurrence; Remission Induction; Risk Factors; Time Factors; Tretinoin

To evaluate a regimen including high-dose mitoxantrone in previously untreated adults with AML, 45 patients aged 21-59 (median 41) were given cytarabine, 3 g/m2 days 1-5, mitoxantrone, 80 mg/m2 day 2 and etoposide, 150 mg/m2 days 1,3,5. Post-remission therapy consisted of 5 cycles combining the same agents at reduced doses. Complete remission was seen in 36 patients. The observed 3-year survival is 28%. Cytogenetic pattern and CD34 expression correlated with response and survival. Significant toxicity included myelosuppression, mucositis, diarrhea and hyperbilirubinemia. Ventricular ejection fraction was generally reduced, with clinical cardiac dysfunction in only 2 patients. This high-dose mitoxantrone combination can be administered to young adults with AML with tolerable toxicity and results comparable to those of other dose-intensive regimens.

Topics: Actuarial Analysis; Acute Disease; Adult; Antineoplastic Combined Chemotherapy Protocols; Bone Marrow Transplantation; Combined Modality Therapy; Conjunctivitis; Cytarabine; Disease-Free Survival; Etoposide; Female; Gastrointestinal Diseases; Humans; Hyperbilirubinemia; Leukemia, Myeloid; Male; Methylprednisolone; Middle Aged; Mitoxantrone; Remission Induction; Risk; Stomatitis; Stroke Volume; Survival Analysis; Survival Rate; Treatment Outcome; Tretinoin; Ventricular Dysfunction, Left

Between May 1988 and March 1995, 359 children with acute myeloid leukaemia (AML) were treated in the MRC AML 10 trial. Three risk groups were identified based on cytogenetics and response to treatment. One hundred and twenty-five children relapsed--103 in the bone marrow only, 12 in the bone marrow combined with other sites, and six had isolated extramedullary relapses (site was not known in four cases). Eighty-seven children received further combination chemotherapy, one all-trans retinoic acid for acute promyelocytic leukaemia, and one a matched unrelated donor allograft in relapse, and 61 achieved a second remission. One patient with no details on reinduction therapy also achieved second remission. Treatment in second remission varied--44 children received a BMT (22 autografts, 12 matched unrelated donor allografts, 10 family donor allografts), and 17 were treated with chemotherapy alone. The overall survival rate for all children (treated and untreated) was 24% at 3 years, with a disease-free survival of 44% for those achieving a second remission. Length of first remission was the most important factor affecting response rates--children with a first remission of less than 1 year fared poorly (second remission rate 36%, 3 year survival 11%), whereas those with longer first remissions had a higher response rate (second remission rate 75%, 3 year survival 49%, P < 0.0001).

Topics: Acute Disease; Adolescent; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Bone Marrow Transplantation; Child; Clinical Protocols; Disease-Free Survival; Follow-Up Studies; Humans; Leukemia, Myeloid; Recurrence; Survival Analysis; Transplantation, Autologous; Transplantation, Homologous; Tretinoin; United Kingdom

Preclinical data suggest that retinoids, eg, all-trans retinoic acid (ATRA), lower concentrations of antiapoptotic proteins such as bcl-2, possibly thereby improving the outcome of anti-acute myeloid leukemia (AML) chemotherapy. Granulocyte colony-stimulating factor (G-CSF) has been considered to be potentially synergistic with ATRA in this regard. Accordingly, we randomized 215 patients with newly diagnosed AML (153 patients) or high-risk myelodysplastic syndrome (MDS) (refractory anemia with excess blasts [RAEB] or RAEB-t, 62 patients) to receive fludarabine + ara-C + idarubicin (FAI) alone, FAI + ATRA, FAI + G-CSF, or FAI + ATRA + G-CSF. Eligibility required one of the following: age over 71 years, a history of abnormal blood counts before M.D. Anderson (MDA) presentation, secondary AML/MDS, failure to respond to one prior course of chemotherapy given outside MDA, or abnormal renal or hepatic function. For the two treatment arms containing ATRA, ATRA was given 2 days (day-2) before beginning and continued for 3 days after completion of FAI. For the two treatment arms including G-CSF, G-CSF began on day-1 and continued until neutrophil recovery. Patients with white blood cell (WBC) counts >50,000/microL began ATRA on day 1 and G-CSF on day 2. Events (death, failure to achieve complete remission [CR], or relapse from CR) have occurred in 77% of the 215 patients. Reflecting the poor prognosis of the patients entered, the CR rate was only 51%, median event-free survival (EFS) time once in CR was 36 weeks, and median survival time was 28 weeks. A Cox regression analysis indicated that, after accounting for patient prognostic variables, none of the three adjuvant treatment combinations (FAI + ATRA, FAI + G, FAI + ATRA + G) affected survival, EFS, or EFS once in CR compared with FAI. Similarly, there were no significant effects of either ATRA ignoring G-CSF, or of G-CSF ignoring ATRA. As previously found, a diagnosis of RAEB or RAEB-t rather than AML was insignificant. There were no indications that the effect of ATRA differed according to cytogenetic group, diagnosis (AML or MDS), or treatment schedule. Logistic regression analysis indicated that, after accounting for prognosis, addition of G-CSF +/- ATRA to FAI improved CR rate versus either FAI or FAI + ATRA, but G-CSF had no effect on the other outcomes. We conclude that addition of ATRA +/- G-CSF to FAI had no effect on CR rate, survival, EFS, or EFS in CR in poor prognosis, newly diagnosed AML or high-r

Topics: Acute Disease; Aged; Antineoplastic Combined Chemotherapy Protocols; Combined Modality Therapy; Cytarabine; Granulocyte Colony-Stimulating Factor; Humans; Idarubicin; Leukemia, Myeloid; Middle Aged; Myelodysplastic Syndromes; Probability; Prognosis; Survival Rate; Time Factors; Tretinoin; Vidarabine

We report a single institution sequential trial of two maintenance treatment regimens for patients with acute myelogenous leukemia (AML). A total of 175 consecutive patients with AML received initial remission induction therapy with high-dose cytosine arabinoside (ara-C) and glucocorticoids. For the initial 63 patients (group A), the control population, planned maintenance treatment was with conventional-dose ara-C given over 4 days for up to 18 months. The subsequent 107 patients (group B) had planned maintenance therapy of up to 6 courses of daunorubicin, ara-C and prednisone and daily cis-retinoic acid for up to two years. The presenting features of group A and B patients were similar as were the response to remission induction, 60 and 52%, respectively. Severe neurological toxicity was encountered once after high-dose ara-C; no drug-related deaths occurred during maintenance treatment. Median duration of remission for group B patients was 9.9 months compared with 5.5 for group A (p = 0.0685). Median survival duration for the two groups was similar, 9.1 months for group A and 10.4 for group B. Survival of patients in group B who attained a complete remission was significantly better than that of patients in group A (p = 0.0439). The studies confirm our initial experience with remission induction using single agent high-dose ara-C and suggest a positive role for maintenance therapy in AML.

Topics: Acute Disease; Adult; Age Factors; Antineoplastic Combined Chemotherapy Protocols; Bone Marrow Transplantation; Combined Modality Therapy; Cytarabine; Daunorubicin; Humans; Leukemia, Myeloid; Middle Aged; Prednisone; Survival Analysis; Tretinoin

Topics: Acute Disease; Antineoplastic Combined Chemotherapy Protocols; Carboplatin; Cytarabine; Daunorubicin; Drug Evaluation; Etoposide; Humans; Idarubicin; Leukemia, Myeloid; Middle Aged; Mitoxantrone; Remission Induction; Tretinoin

Topics: Acute Disease; Appendicitis; Blood Coagulation Disorders; Child; Humans; Leukemia, Promyelocytic, Acute; Leukemic Infiltration; Tretinoin

Topics: Acute Disease; Humans; Leukemia, Promyelocytic, Acute; Pancreatitis; Tretinoin

CD137, a potent costimulatory receptor for CD8

Topics: Acute Disease; Adenylate Kinase; Aldehyde Oxidoreductases; Animals; Antigens, CD; Apoptosis; CD11b Antigen; Cell Differentiation; Colitis; Dendritic Cells; Disease Susceptibility; Forkhead Transcription Factors; Integrin alpha Chains; Intestines; MAP Kinase Kinase Kinases; Mice, Inbred C57BL; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Signal Transduction; T-Lymphocytes, Regulatory; Th17 Cells; Tretinoin; Tumor Necrosis Factor Receptor Superfamily, Member 9

A 55-year-old woman developed acute promyelocytic leukaemia during treatment with all-trans-retinoic acid and arsenic trioxide. Initially, she presented with symptoms of epigastric pain, vomiting, and nausea, and she developed acute pancreatitis. She was treated with parenteral nutritional supplementation for 20 days. However, the patient continued to develop refractory hyponatraemia, hypotension, and apathy. Finally, the patient was diagnosed with Wernicke encephalopathy (WE) using head magnetic resonance imaging. The patient underwent high-dose intravenous thiamine administration, and her symptoms were alleviated. WE is a rare adverse event during acute pancreatitis therapy. Acute pancreatitis that is caused by all-trans-retinoic acid and arsenic trioxide is a rare complication of acute promyelocytic leukaemia during chemotherapy. Further study is essential to improve our comprehension of the risk factors for complications in patients with acute promyelocytic leukaemia, considering that the associated complications were potentially caused by multiple etiological factors. A better understanding of these risk factors may help to improve the prognosis of patients with acute promyelocytic leukaemia at an early stage.

Topics: Acute Disease; Arsenic Trioxide; Arsenicals; Female; Humans; Leukemia, Promyelocytic, Acute; Middle Aged; Oxides; Pancreatitis; Tretinoin; Wernicke Encephalopathy

To investigate the clinical features of and therapeutic options for a rare morphology resembling APL with t (11;12) (p15;q13) in acute myeloid leukemia.. One case of APL-like acute leukemia with a t (11;12) (p15;q13) translocation is reported and related literature is retrospectively reviewed.. A rare acute myeloid leukemia with a t (11;12) (p15;q13) translocation was diagnosed by morphology, immunophenotyping, chromosome analysis, and fusion gene detection, without finding a classical t (15;17) (q24.1;q21.1) translocation and the PML-RARa fusion gene. The patient responded poorly to differentiation induction therapy with all-trans retinoic acid (ATRA) and arsenic trioxide (ATO). In the three previous cases re-ported, poor results were obtained with ATRA and/or ATO therapy.. We reported a rare meaningful AML patient with t (11;12) (p15;q13). Standard AML regimens may be preferred. These APL-like leukemias may benefit from hematopoietic stem cell transplantation treatment. Further investigation involving more cases is needed to determine the role of t (11;12) (p15;q13) in AML and to find better therapy choices.

Topics: Acute Disease; Antineoplastic Agents; Arsenic Trioxide; Chromosomes, Human, Pair 11; Chromosomes, Human, Pair 12; Humans; Leukemia, Myeloid; Male; Oncogene Proteins, Fusion; Review Literature as Topic; Translocation, Genetic; Treatment Outcome; Tretinoin; Young Adult

We report a rare case of hypercalcemia and acute pancreatitis in a subject with acute promyelocytic leukemia (APL) and pulmonary tuberculosis, during all-trans-retinoic acid (ATRA) treatment. Both associated complications were potentially due to several causes. A careful monitoring and exclusion of all causative factors must be addressed. Further research is necessary to improve our understanding of risk factors for these complications in patients with (APL). Studying these patterns may help us to improve outcomes for all children and young adults with hematologic malignancies.

Topics: Acute Disease; Antineoplastic Combined Chemotherapy Protocols; Asparaginase; Causality; Febrile Neutropenia; Humans; Hypercalcemia; Leukemia, Promyelocytic, Acute; Male; Mercaptopurine; Methotrexate; Middle Aged; Models, Biological; Pancreatitis; Pleural Effusion; Prednisone; Pulmonary Aspergillosis; Risk Factors; Tretinoin; Tuberculosis, Pulmonary; Vincristine

Adoptively transferred regulatory T-cells represent a promising therapeutic approach for tolerance induction in autoimmunity and transplantation medicine. However, a major hurdle for clinical application is the manufacturing of sufficient Treg cell numbers with respect to the low frequency of naturally occurring Tregs in the peripheral blood. Therefore, ex vivo large-scale expansion is mandatory for most of the clinical conditions. Besides the Treg cell number other parameters of the cell product are of high relevance for safe and efficient clinical Treg cell application like Treg cell purity, suppressive capacity and genetic stability of the Treg cell phenotype. Moreover, migratory properties of ex vivo expanded Tregs should be defined very clearly in order to predict their migration to secondary lymphoid organs as sites of antigen-specific activation, in vivo proliferation and subsequent trafficking to affected target organs. Therefore, we studied different cell culture conditions for Treg large-cell expansion using all-trans retinoic acid (ATRA) and/or rapamycin (Rapa) with focus on their migratory properties. The tested culture conditions revealed comparable chemokine receptor expression profiles (CXCR3, CCR4, CCR6, CCR7) and functional migration capabilities (IP10 and CCL19) with respect to Th1 and Th2 inflammatory conditions. However, the most striking difference was detected for the expansion capacity, suppressive potency and genetic stability likely predisposing large-scale expansion with ATRA and/or Rapa for therapeutic intervention in acute GvHD and without supplementation for chronic GvHD.

Topics: Acute Disease; Cell Culture Techniques; Cell Movement; Cell Proliferation; Cells, Cultured; Chronic Disease; Graft vs Host Disease; Humans; Immune Tolerance; Immunotherapy, Adoptive; Receptors, Chemokine; Sirolimus; T-Lymphocytes, Regulatory; Th1 Cells; Th1-Th2 Balance; Th2 Cells; Transcriptome; Tretinoin

Treatment of acute promyelocytic leukemia (APL) with all-trans retinoic acid (ATRA) is the first example of targeted therapy. In fact, the oncogenic fusion-protein (PML-RAR) typical of this leukemia contains the retinoid-nuclear-receptor RARα. PML-RAR is responsible for the differentiation block of the leukemic blast. Besides PML-RAR, two endogenous RARα proteins are present in APL blasts, i.e. RARα1 and RARα2. We developed different cell populations characterized by PML-RAR, RARα2 and RARα1 knock-down in the APL-derived NB4 cell-line. Unexpectedly, silencing of PML-RAR and RARα2 results in similar increases in the constitutive expression of several granulocytic differentiation markers. This is accompanied by enhanced expression of the same granulocytic markers upon exposure of the NB4 blasts to ATRA. Silencing of PML-RAR and RARα2 causes also similar perturbations in the whole genome gene-expression profiles of vehicle and ATRA treated NB4 cells. Unlike PML-RAR and RARα2, RARα1 knock-down blocks ATRA-dependent induction of several granulocytic differentiation markers. Many of the effects on myeloid differentiation are confirmed by over-expression of RARα2 in NB4 cells. RARα2 action on myeloid differentiation does not require the presence of PML-RAR, as it is recapitulated also upon knock-down in PML-RAR-negative HL-60 cells. Thus, relative to RARα1, PML-RAR and RARα2 exert opposite effects on APL-cell differentiation. These contrasting actions may be related to the fact that both PML-RAR and RARα2 interact with and inhibit the transcriptional activity of RARα1. The interaction surface is located in the carboxy-terminal domain containing the D/E/F regions and it is influenced by phosphorylation of Ser-369 of RARα1.

Topics: Acute Disease; Animals; Antineoplastic Agents; Cell Differentiation; Cell Line, Tumor; Cell Survival; Chlorocebus aethiops; COS Cells; Gene Expression Regulation, Leukemic; HL-60 Cells; Humans; Leukemia, Myeloid; Oncogene Proteins, Fusion; Retinoic Acid Receptor alpha; RNA Interference; Tretinoin

Topics: Acute Disease; Adolescent; Antineoplastic Agents; Arsenic Trioxide; Arsenicals; Electrocardiography; Humans; Leukemia, Promyelocytic, Acute; Maintenance Chemotherapy; Male; Oxides; Pericarditis; Remission Induction; Tretinoin

Topics: Acute Disease; Adenocarcinoma; Antineoplastic Agents; Capecitabine; Chemoradiotherapy; Colorectal Neoplasms; Female; Humans; Idarubicin; Leukemia, Promyelocytic, Acute; Middle Aged; Neoplasms, Second Primary; Organoplatinum Compounds; Oxaliplatin; Pancytopenia; Primary Myelofibrosis; Remission Induction; Tretinoin

Gap junctional intercellular communication (GJIC) is typically decreased in malignant tumors. Gap junction is not presented between hematopoietic cells but occurred in bone marrow stromal cells (BMSCs). Connexin 43 (Cx43) is the major gap junction (GJ) protein; our previous study revealed that Cx43 expression and GJIC were decreased in acute leukemic BMSCs. All-trans retinoic acid (ATRA) increases GJIC in a variety of cancer cells and has been used to treat acute promyelocytic leukemia, but the effects of ATRA on leukemic BMSCs is unknown. In this study, we evaluated the potential effects of ATRA on cell cycle, proliferation, and apoptosis of leukemic BMSCs. Effects of ATRA on Cx43 expression and GJIC were also examined.. Human BMSCs obtained from 25 patients with primary acute leukemia, and 10 normal healthy donors were cultured. Effects of ATRA on cell cycle, cell proliferation, and apoptosis were examined with or without co-treatment with amphotericin-B. Cx43 expression was examined at both the mRNA and protein expression levels. GJIC was examined by using a dye transfer assay and measuring the rate of fluorescence recovery after photobleaching (FRAP).. ATRA arrested the cell cycle progression, inhibited cell growth, and increased apoptosis in leukemic BMSCs. Both Cx43 expression and GJIC function were increased by ATRA treatment. Most of the observed effects mediated by ATRA were abolished by amphotericin-B pretreatment.. ATRA arrests cell cycle progression in leukemic BMSCs, likely due to upregulating Cx43 expression and enhancing GJIC function.

Topics: Acute Disease; Adult; Amphotericin B; Antineoplastic Agents; Apoptosis; Blotting, Western; Cell Communication; Cell Cycle Checkpoints; Cell Proliferation; Cells, Cultured; Connexin 43; Female; Fluorescence Recovery After Photobleaching; Gap Junctions; Gene Expression; Humans; Leukemia, Myeloid; Male; Mesenchymal Stem Cells; Microscopy, Confocal; Reverse Transcriptase Polymerase Chain Reaction; Tretinoin

The transfer of alloreactive regulatory T (aTreg) cells into transplant recipients represents an attractive treatment option to improve long-term graft acceptance. We recently described a protocol for the generation of aTreg cells in mice using a nondepleting anti-CD4 antibody (aCD4). Here, we investigated whether adding TGF-β and retinoic acid (RA) or rapamycin (Rapa) can further improve aTreg-cell generation and function. Murine CD4(+) T cells were cultured with allogeneic B cells in the presence of aCD4 alone, aCD4+TGF-β+RA or aCD4+Rapa. Addition of TGF-β+RA or Rapa resulted in an increase of CD25(+)Foxp3(+)-expressing T cells. Expression of CD40L and production of IFN-γ and IL-17 was abolished in aCD4+TGF-β+RA aTreg cells. Additionally, aCD4+TGF-β+RA aTreg cells showed the highest level of Helios and Neuropilin-1 co-expression. Although CD25(+)Foxp3(+) cells from all culture conditions displayed complete demethylation of the Treg-specific demethylated region, aCD4+TGF-β+RA Treg cells showed the most stable Foxp3 expression upon restimulation. Consequently, aCD4+TGF-β+RA aTreg cells suppressed effector T-cell differentiation more effectively in comparison to aTreg cells harvested from all other cultures, and furthermore inhibited acute graft versus host disease and especially skin transplant rejection. Thus, addition of TGF-β+RA seems to be superior over Rapa in stabilising the phenotype and functional capacity of aTreg cells.

Topics: Acute Disease; Allografts; Animals; Antibiotics, Antineoplastic; Antibodies, Monoclonal, Murine-Derived; B-Lymphocytes; CD4 Antigens; CD40 Ligand; Cell Differentiation; Cells, Cultured; Coculture Techniques; Forkhead Transcription Factors; Gene Expression Regulation; Graft vs Host Disease; Interleukin-2 Receptor alpha Subunit; Mice; Mice, Inbred BALB C; Mice, Knockout; Sirolimus; Skin Transplantation; T-Lymphocytes, Regulatory; Transforming Growth Factor beta; Tretinoin

Stem cell therapy is a potential strategy to treat patients with Parkinson's disease (PD); however, several practical limitations remain. As such, finding the appropriate stem cell remains the primary issue in regenerative medicine today. We isolated a pre-placental pluripotent stem cell from the chorionic villi of women with early tubal ectopic pregnancies. Our objectives in this study were (i) to identify the characteristics of hTS cells as a potential cell source for therapy; and (ii) to test if hTS cells can be used as a potential therapeutic strategy for PD.. hTS cells expressed gene markers of both the trophectoderm (TE) and the inner cell mass (ICM). hTS cells exhibited genetic and biological characteristics similar to that of hES cells, yet genetically distinct from placenta-derived mesenchymal stem cells. All-trans retinoic acid (RA) efficiently induced hTS cells into trophoblast neural stem cells (tNSCs) in 1-day. Overexpression of transcription factor Nanog was possibly achieved through a RA-induced non-genomic c-Src/Stat3/Nanog signaling pathway mediated by the subcellular c-Src mRNA localization for the maintenance of pluripotency in tNSCs. tNSC transplantation into the lesioned striatum of acute and chronic PD rats not only improved behavioral deficits but also regenerated dopaminergic neurons in the nigrostriatal pathway, evidenced by immunofluorescent and immunohistological analyses at 18-weeks. Furthermore, tNSCs showed immunological advantages for the application in regenerative medicine.. We successfully isolated and characterized the unique ectopic pregnancy-derived hTS cells. hTS cells are pluripotent stem cells that can be efficiently induced to tNSCs with positive results in PD rat models. Our data suggest that the hTS cell is a dynamic stem cell platform that is potentially suitable for use in disease models, drug discovery, and cell therapy such as PD.

Topics: Acute Disease; Animals; Behavior, Animal; Cell Proliferation; Chronic Disease; Dopamine; Female; Genome; Humans; Leukemia Inhibitory Factor; Neostriatum; Neural Stem Cells; Parkinson Disease; Pluripotent Stem Cells; Pregnancy; Pregnancy, Ectopic; Rats; Regeneration; Signal Transduction; Tretinoin; Trophoblasts

Topics: Acute Disease; Antineoplastic Agents; Humans; Hypertriglyceridemia; Pancreatitis; Tretinoin

Treg are endowed with immunosuppressive activities and have been proposed as promising targets for the therapy of autoimmune diseases. As the suppressive capacity of Treg depends on their migration into the affected tissues, we tested here whether modulation of Treg homing would enhance their capacity to suppress inflammation in mouse models of inflammatory bowel disease. Retinoic acid (RA) was used to induce the gut-specific homing receptor alpha(4)beta(7) efficiently and, to some extent, the chemokine receptor CCR9 on in vitro expanded Treg. Upon transfer, RA-treated Treg were indeed more potent suppressors in an acute, small intestinal inflammation model, compared with Treg stimulated without RA. By contrast, the efficacy of Treg to resolve an established, chronic inflammation of the colon in the transfer colitis model was not affected by RA-treatment. In the latter model, a rapid loss of RA-induced alpha(4)beta(7) expression and de novo induction of alpha(4)beta(7) on previously negative cells was observed on transferred Treg, which implies that Treg acquire gut-seeking properties in vivo under inflammatory and/or lymphopenic conditions. Together, our data show that the induction of appropriate homing properties prior to transfer increases the protective potential of adoptively transferred Treg in acute, but not in chronic, inflammatory disorders of the gut.

Topics: Acute Disease; Adoptive Transfer; Animals; Cells, Cultured; Chronic Disease; Colitis; Disease Models, Animal; Homeodomain Proteins; Humans; Immunosuppression Therapy; Inflammation; Inflammatory Bowel Diseases; Integrins; Intestine, Small; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Mice, Transgenic; Receptors, CCR; Receptors, Lymphocyte Homing; T-Lymphocytes, Regulatory; Tretinoin

The peptidyl-prolyl-isomerase Pin1 interacts with phosphorylated proteins, altering their conformation. The retinoic acid receptor RARalpha and the acute-promyelocytic-leukemia-specific counterpart PML-RARalpha directly interact with Pin1. Overexpression of Pin1 inhibits ligand-dependent activation of RARalpha and PML-RARalpha. Inhibition is relieved by Pin1-targeted short interfering RNAs and by pharmacologic inhibition of the catalytic activity of the protein. Mutants of Pin1 catalytically inactive or defective for client-protein-binding activity are incapable of inhibiting ligand-dependent RARalpha transcriptional activity. Functional inhibition of RARalpha and PML-RARalpha by Pin1 correlates with degradation of the nuclear receptors via the proteasome-dependent pathway. In the acute myelogenous leukemia cell lines HL-60 and NB4, Pin1 interacts with RARalpha in a constitutive fashion. Suppression of Pin1 by a specific short hairpin RNA in HL-60 or NB4 cells stabilizes RARalpha and PML-RARalpha, resulting in increased sensitivity to the cytodifferentiating and antiproliferative activities of all-trans retinoic acid. Treatment of the two cell lines and freshly isolated acute myelogenous leukemia blasts (M1 to M4) with ATRA and a pharmacologic inhibitor of Pin1 causes similar effects. Our results add a further layer of complexity to the regulation of nuclear retinoic acid receptors and suggest that Pin1 represents an important target for strategies aimed at increasing the therapeutic index of retinoids.

Topics: Acute Disease; Animals; Antineoplastic Agents; Chlorocebus aethiops; COS Cells; HL-60 Cells; Humans; Leukemia, Myeloid; NIMA-Interacting Peptidylprolyl Isomerase; Oncogene Proteins, Fusion; Peptidylprolyl Isomerase; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Transcriptional Activation; Transfection; Tretinoin

Topics: Acute Disease; Adolescent; Antineoplastic Agents; Female; Humans; Hypertriglyceridemia; Leukemia, Promyelocytic, Acute; Pancreatitis; Tretinoin

Arsenic trioxide (As2O3) is highly efficacious in acute promyelocytic leukemia (APL). Aquaglyceroporin 9 (AQP9) is a transmembrane protein that may be involved in arsenic uptake. In 10 of 11 myeloid and lymphoid leukemia lines, quantitative polymerase chain reaction (Q-PCR) and Western blotting showed that AQP9 expression correlated positively with As2O3-induced cytotoxicity. As a proof-of-principle, transfection of EGFP-tagged AQP9 to the hepatoma line Hep3B, not expressing AQP9 and As2O3 insensitive, led to membrane AQP9 expression and increased As2O3-induced cytotoxicity. Similarly, the chronic myeloid leukemia line K562 expressed low levels of AQP9 and was As2O3 insensitive. The K562(EGFP-AQP9) transfectant accumulated significantly higher levels of intracellular arsenic than control K562(EGFP) when incubated with As2O3, resulting in significantly increased As2O3-induced cytotoxicity. Pretreatment of the myeloid leukemia line HL-60 with all-trans retinoic acid (ATRA) up-regulated AQP9, leading to a significantly increased arsenic uptake and As2O3-induced cytotoxicity on incubation with As2O3, which might explain the synergism between ATRA and As2O3. Therefore, AQP9 controlled arsenic transport and might determine As2O3 sensitivity. Q-PCR showed that primary APL cells expressed AQP9 significantly (2-3 logs) higher than other acute myeloid leukemias (AMLs), which might explain their exquisite As2O3 sensitivity. However, APL and AML with maturation expressed comparable AQP9 levels, suggesting that AQP9 expression was related to granulocytic maturation.

Topics: Acute Disease; Aquaporins; Arsenic Trioxide; Arsenicals; Cell Line, Tumor; Cell Proliferation; Gene Expression Profiling; Humans; K562 Cells; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Oxides; Point Mutation; Reverse Transcriptase Polymerase Chain Reaction; Sensitivity and Specificity; Tretinoin; Up-Regulation

Alteration of lineage-specific transcriptional programs for hematopoiesis causes differentiation block and promotes leukemia development. Here, we show that AML1/ETO, the most common translocation fusion product in acute myeloid leukemia (AML), counteracts the activity of retinoic acid (RA), a transcriptional regulator of myelopoiesis. AML1/ETO participates in a protein complex with the RA receptor alpha (RARalpha) at RA regulatory regions on RARbeta2, which is a key RA target gene mediating RA activity/resistance in cells. At these sites, AML1/ETO recruits histone deacetylase, DNA methyltransferase, and DNA-methyl-CpG binding activities that promote a repressed chromatin conformation. The link among AML1/ETO, heterochromatic RARbeta2 repression, RA resistance, and myeloid differentiation block is indicated by the ability of either siRNA-AML1/ETO or the DNA methylation inhibitor 5-azacytidine to revert these epigenetic alterations and to restore RA differentiation response in AML1/ETO blasts. Finally, RARbeta2 is commonly silenced by hypermethylation in primary AML blasts but not in normal hematopoietic precursors, thus suggesting a role for the epigenetic repression of the RA signaling pathway in myeloid leukemogenesis.

Topics: Acute Disease; Cell Differentiation; Cells, Cultured; Core Binding Factor Alpha 2 Subunit; Gene Expression Regulation, Leukemic; Gene Silencing; Heterochromatin; Humans; Leukemia, Myeloid; Oncogene Proteins, Fusion; Protein Binding; Receptors, Retinoic Acid; Response Elements; Retinoid X Receptors; RUNX1 Translocation Partner 1 Protein; Signal Transduction; Transfection; Tretinoin; U937 Cells

Programmed cell death-4 (PDCD4) is a recently discovered tumor suppressor protein that inhibits protein synthesis by suppression of translation initiation. We investigated the role and the regulation of PDCD4 in the terminal differentiation of acute myeloid leukemia (AML) cells. Expression of PDCD4 was markedly up-regulated during all-trans retinoic acid (ATRA)-induced granulocytic differentiation in NB4 and HL60 AML cell lines and in primary human promyelocytic leukemia (AML-M3) and CD34(+) hematopoietic progenitor cells but not in differentiation-resistant NB4.R1 and HL60R cells. Induction of PDCD4 expression was associated with nuclear translocation of PDCD4 in NB4 cells undergoing granulocytic differentiation but not in NB4.R1 cells. Other granulocytic differentiation inducers such as DMSO and arsenic trioxide also induced PDCD4 expression in NB4 cells. In contrast, PDCD4 was not up-regulated during monocytic/macrophagic differentiation induced by 1,25-dihydroxyvitamin D3 or 12-O-tetradecanoyl-phorbol-13-acetate in NB4 cells or by ATRA in THP1 myelomonoblastic cells. Knockdown of PDCD4 by RNA interference (siRNA) inhibited ATRA-induced granulocytic differentiation and reduced expression of key proteins known to be regulated by ATRA, including p27(Kip1) and DAP5/p97, and induced c-myc and Wilms' tumor 1, but did not alter expression of c-jun, p21(Waf1/Cip1), and tissue transglutaminase (TG2). Phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway was found to regulate PDCD4 expression because inhibition of PI3K by LY294002 and wortmannin or of mTOR by rapamycin induced PDCD4 protein and mRNA expression. In conclusion, our data suggest that PDCD4 expression contributes to ATRA-induced granulocytic but not monocytic/macrophagic differentiation. The PI3K/Akt/mTOR pathway constitutively represses PDCD4 expression in AML, and ATRA induces PDCD4 through inhibition of this pathway.

Topics: Acute Disease; Antineoplastic Agents; Apoptosis; Apoptosis Regulatory Proteins; Arsenic Trioxide; Arsenicals; Blotting, Western; Cell Differentiation; Cell Line, Tumor; Cell Proliferation; Cyclin-Dependent Kinase Inhibitor p27; Fluorescent Antibody Technique; Gene Expression Regulation, Neoplastic; Genes, Tumor Suppressor; Granulocytes; HL-60 Cells; Humans; Leukemia, Myeloid; Macrophages; Monocytes; Oxides; Protein Transport; Proto-Oncogene Proteins c-akt; RNA-Binding Proteins; RNA, Small Interfering; Tretinoin

The death-associated protein kinase 2 (DAPK2) belongs to a family of Ca(2+)/calmodulin-regulated serine/threonine kinases involved in apoptosis. During investigation of candidate genes operative in granulopoiesis, we identified DAPK2 as highly expressed. Subsequent investigations demonstrated particularly high DAPK2 expression in normal granulocytes compared with monocytes/macrophages and CD34(+) progenitor cells. Moreover, significantly increased DAPK2 mRNA levels were seen when cord blood CD34(+) cells were induced to differentiate toward neutrophils in tissue culture. In addition, all-trans retinoic acid (ATRA)-induced neutrophil differentiation of two leukemic cell lines, NB4 and U937, revealed significantly higher DAPK2 mRNA expression paralleled by protein induction. In contrast, during differentiation of CD34(+) and U937 cells toward monocytes/macrophages, DAPK2 mRNA levels remained low. In primary leukemia, low expression of DAPK2 was seen in acute myeloid leukemia samples, whereas chronic myeloid leukemia samples in chronic phase showed intermediate expression levels. Lentiviral vector-mediated expression of DAPK2 in NB4 cells enhanced, whereas small interfering RNA-mediated DAPK2 knockdown reduced ATRA-induced granulocytic differentiation, as evidenced by morphology and neutrophil stage-specific maturation genes, such as CD11b, G-CSF receptor, C/EBPepsilon, and lactoferrin. In summary, our findings implicate a role for DAPK2 in granulocyte maturation.

Topics: Acute Disease; Antigens, CD34; Antigens, Differentiation; Apoptosis Regulatory Proteins; Calcium-Calmodulin-Dependent Protein Kinases; Cell Differentiation; Cell Line, Tumor; Chronic Disease; Death-Associated Protein Kinases; Gene Expression Profiling; Granulocytes; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid; Myeloid Cells; Myelopoiesis; Neutrophils; RNA, Small Interfering; Tretinoin; Up-Regulation

Natural killer (NK) cells are potent effectors of innate antitumor defense and are currently exploited for immune-based therapy of human leukemia. However, malignant blood cells in acute myeloid leukemia (AML) display low levels of ligands for the activating immunoreceptor NKG2D and can thus evade NK immunosurveillance. We examined the possibility of up-regulating NKG2D-specific UL16-binding protein (ULBP) ligands using anti-neoplastic compounds with myeloid differentiation potential. Combinations of 5-aza-2'-deoxycytidine, trichostatin A, vitamin D3, bryostatin-1, and all-trans-retinoic acid, used together with myeloid growth factors and interferon-gamma, increased cell surface ULBP expression up to 10-fold in the AML cell line HL60 and in primary AML blasts. Up-regulation of ULBP ligands was associated with induction of myelomonocytic differentiation of AML cells. Higher ULBP expression increased NKG2D-dependent sensitivity of HL60 cells to NK-mediated killing. These findings identify NKG2D ligands as targets of leukemia differentiation therapy and suggest a clinical benefit in combining a pharmacological approach with NK cell-based immunotherapy in AML.

Topics: Acute Disease; Antineoplastic Combined Chemotherapy Protocols; Azacitidine; Bryostatins; Cell Differentiation; Cell Line, Tumor; Cholecalciferol; Cytotoxicity, Immunologic; Decitabine; Flow Cytometry; GPI-Linked Proteins; Humans; Hydroxamic Acids; Intercellular Signaling Peptides and Proteins; Killer Cells, Natural; Leukemia, Myeloid; Reverse Transcriptase Polymerase Chain Reaction; Tretinoin; Up-Regulation

The tumor antigen preferentially expressed antigen of melanoma (PRAME) is frequently overexpressed in a wide variety of malignant diseases, including acute myeloid leukemia (AML). It was recently shown that PRAME can function as a repressor of retinoic acid signaling, as indicated by down-regulation of retinoic acid receptor-beta (RARB) and cyclin-dependent kinase inhibitor 1A (CDKN1A). Another study suggested that PRAME can induce caspase-independent apoptosis via down-regulation of heat shock 27-kDa protein 1 (HSPB1) and S100 calcium-binding protein A4 (S100A4). The transcriptional repression of PRAME depends on the formation of a complex with the enhancer of zeste homolog 2 (EZH2). To test whether these mechanisms play an important roll in AML, we analyzed the expression of PRAME, EZH2, RARB, HSPB1, S100A4, and CDKN1A by real-time polymerase chain reaction in primary leukemic cells from 52 children with AML. All genes were expressed in many patients, but the level of expression of the last four genes was not associated with either PRAME expression or PRAME and EZH2 co-expression. In conclusion, the above mechanisms do not seem to play a major role in the pathogenesis of AML; they could be neutralized by other pathways that affect the same targets.

Topics: Acute Disease; Adolescent; Adult; Antigens, Neoplasm; Biomarkers, Tumor; Child; Child, Preschool; Cyclin-Dependent Kinase Inhibitor p21; DNA-Binding Proteins; Down-Regulation; Enhancer of Zeste Homolog 2 Protein; Female; Gene Expression Regulation, Neoplastic; Heat-Shock Proteins; HSP27 Heat-Shock Proteins; Humans; Infant; Infant, Newborn; Leukemia, Myeloid; Male; Molecular Chaperones; Neoplasm Proteins; Polycomb Repressive Complex 2; Receptors, Retinoic Acid; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; RNA, Neoplasm; S100 Calcium-Binding Protein A4; S100 Proteins; Signal Transduction; Transcription Factors; Tretinoin

To investigate pig7 expression level in acute leukemia (AL) and its clinical significance and explore the possible mechanisms for pig7 silence in terms of methylation control.. Expression levels of pig7 mRNA in bone marrow samples from 138 patients with de novo AL and 21 normal controls and in 6 leukemic cell lines were detected by quantitative real-time reverse transcription PCR (RT-PCR). Differentiation induction effect by all-trans retinoic acid (ATRA) and concomitant change in pig7 expression were also monitored in NB4 cells. Endonuclease analysis was employed to determined the identity of pig7 transcript present in AL samples. Methylation specific PCR (MSP) was used to elucidate if hypermethylation was responsible for pig7 silence in AL.. Compared with that in normal control, pig7 expression was markedly decreased (0.62 vs 18.30, median, P < 0.01) in AL patients on progression (at diagnosis, relapse or refractory). No significant difference was observed between acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL). AL at diagnosis had a higher pig7 level than those with relapsed or refractory disease (1.43 vs 0.16, median, P < 0.05). The complete remission (CR) rate after chemotherapy was found to be significantly correlated with pig7 expression levels (P < 0.05). Differentiated NB4 cells showed an increased level of pig7 expression (from 1.61 +/- 0.72 to 44.75 +/- 3.93, P < 0.01). Only one form of pig7 transcripts i.e., Small integral membrane protein of late endosome (SIMPLE), was detected in AL patients. Hypermethylation of pig7 promoter was identified in K562 and HL-60 cells, in contrast to non-methylation predominant in U937 cells.. Aberrant down-regulation of pig7 provides novel insights into leukemogenesis and therapy response prediction in AL.

Topics: Acute Disease; Cell Differentiation; Cell Line, Tumor; DNA Methylation; Gene Expression Regulation, Leukemic; Humans; Leukemia; Nuclear Proteins; Promoter Regions, Genetic; RNA, Messenger; Transcription Factors; Tretinoin

In this issue of the Journal, Soucek et al. challenge the assumption that increased functional granulocytic maturation of HL-60, an ATRA-responsive acute myeloid leukemia cell line devoid of the APL-specific PML-RARalpha fusion protein, results in more rapid or more sustained cell death. In this model cell line, the authors demonstrate that TGFbeta1, a well-known haemopoietic growth factor, enhances retinoid-dependent cyto-differentiation and growth arrest while inhibiting apoptosis. Concomitantly, treatment of HL-60 cells with the combination of TGFbeta1 and the retinoid partially suppresses ATRA-dependent induction of TRAIL. This is a death receptor ligand of the TNF family implicated in the paracrine mechanism underlying the apoptotic action of ATRA in APL blasts The protein activates the death-receptor-dependent or extrinsic apoptotic pathway, which is associated with caspase-8 activation. Down-regulation of TRAIL is correlated to an increase in the levels of the anti-apoptotic c-FLIP(L) and Mcl-1 proteins that are likely to be involved in the suppression of caspase-8 activation and apoptosis.

Topics: Acute Disease; Apoptosis; Apoptosis Regulatory Proteins; CASP8 and FADD-Like Apoptosis Regulating Protein; Caspase 8; Caspases; Cell Differentiation; Cell Proliferation; Granulocytes; HL-60 Cells; Humans; Intracellular Signaling Peptides and Proteins; Leukemia, Myeloid, Acute; Membrane Glycoproteins; Myeloid Cell Leukemia Sequence 1 Protein; Neoplasm Proteins; Peptide Fragments; Proto-Oncogene Proteins c-bcl-2; TNF-Related Apoptosis-Inducing Ligand; Transforming Growth Factor beta; Transforming Growth Factor beta1; Tretinoin; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha

Acute myeloid leukemia (AML) blasts are immature committed myeloid cells unable to spontaneously undergo terminal maturation, and characterized by heterogeneous sensitivity to natural differentiation inducers. Here, we show a molecular signature predicting the resistance or sensitivity of six myeloid cell lines to differentiation induced in vitro with retinoic acid or vitamin D. The identified signature was further validated by TaqMan assay for the prediction of response to an in vitro differentiation assay performed on 28 freshly isolated AML blast populations. The TaqMan assay successfully predicts the in vitro resistance or responsiveness of AML blasts to differentiation inducers. Furthermore, performing a meta-analysis of publicly available microarray data sets, we also show the accuracy of our prediction on known phenotypes and suggest that our signature could become useful for the identification of patients eligible for new therapeutic strategies.

Topics: Acute Disease; Antineoplastic Agents; Cell Differentiation; Cell Line, Tumor; Cluster Analysis; Databases, Factual; Drug Resistance, Neoplasm; Gene Expression Regulation, Leukemic; Humans; Leukemia, Myeloid; Meta-Analysis as Topic; Oligonucleotide Array Sequence Analysis; Predictive Value of Tests; Reverse Transcriptase Polymerase Chain Reaction; Tretinoin; Vitamin D; Vitamins

We show that common heterochromatin antigenic protein markers [HP1alpha, -beta, -gamma and mono-, di-, and trimethylated histone H3 lysine 9 (H3K9)], although present in human blood progenitor CD34+ cells, differentiated lymphocytes, and monocytes, are absent in neutrophil granulocytes and to large extent, in eosinophils. Monomethylated and in particular, dimethylated H3K9 are present to variable degrees in the granulocytes of chronic myeloid leukemia (CML) patients, without being accompanied by HP1 proteins. In patients with an acute phase of CML and in acute myeloid leukemia patients, strong methylation of H3K9 and all isoforms of HP1 are detected. In chronic forms of CML, no strong correlations among the level of histone methylation, disease progression, and modality of treatment were observed. Histone methylation was found even in "cured" patients without Philadelphia chromosome (Ph) resulting from +(9;22)(q34;q11) BCR/ABL translocation, suggesting an incomplete process of developmentally regulated chromatin remodeling in the granulocytes of these patients. Similarly, reprogramming of leukemia HL-60 cells to terminal differentiation by retinoic acid does not eliminate H3K9 methylation and the presence of HP1 isoforms from differentiated granulocytes. Thus, our study shows for the first time that histone H3 methylation may be changed dramatically during normal cell differentiation. The residual histone H3 methylation in myeloid leukemia cells suggests an incomplete chromatin condensation that may be linked to the leukemia cell proliferation and may be important for the prognosis of disease treatment and relapse.

Topics: Acute Disease; Adult; Aged; Antineoplastic Agents; Biomarkers, Tumor; Cell Differentiation; Cell Proliferation; Chromatin; Chromobox Protein Homolog 5; Disease Progression; Granulocytes; Histones; HL-60 Cells; Humans; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Leukemia, Myeloid; Methylation; Middle Aged; Tretinoin

All-trans-retinoic acid (ATRA) has been successfully used in the treatment of acute promyelocytic leukemia (APL). One of its adverse effects is acute pancreatitis. In the literature, a proposed cause of acute pancreatitis is hypertriglyceridemia. Here, we present the case of a 45-year-old male with APL, treated with ATRA combined with induction chemotherapy (cytarabine and idarubicin), who developed acute pancreatitis without overt hypertriglyceridemia. This finding suggests that hypertriglyceridemia might not be the sole contributing factor in the pathogenesis of ATRA-induced acute pancreatitis and that attention should be paid to the possibility that ATRA treatment causes acute pancreatitis in the absence of overt hypertriglyceridemia.

Topics: Acute Disease; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Humans; Hypertriglyceridemia; Idarubicin; Leukemia, Promyelocytic, Acute; Male; Middle Aged; Pancreatitis; Tretinoin

The AML1/ETO and PML/RARalpha leukemia fusion proteins induce acute myeloid leukemia by acting as transcriptional repressors. They interact with corepressors, such as N-CoR and SMRT, that recruit a multiprotein complex containing histone deacetylases on crucial myeloid differentiation genes. This leads to gene repression contributing to generate a differentiation block. We expressed in leukemia cells containing PML/RARalpha and AML1/ETO N-CoR protein fragments derived from fusion protein/corepressor interaction surfaces. This blocks N-CoR/SMRT binding by these fusion proteins, and disrupts the repressor protein complex. In consequence, the expression of genes repressed by these fusion proteins increases and differentiation response to vitamin D3 and retinoic acid is restored in previously resistant cells. The alteration of PML/RARalpha-N-CoR/SMRT connections triggers proteasomal degradation of the fusion protein. The N-CoR fragments are biologically effective also when directly transduced by virtue of a protein transduction domain. Our data indicate that fusion protein activity is permanently required to maintain the leukemia phenotype and show the route to developing a novel therapeutic approach for leukemia, based on its molecular pathogenesis.

Topics: Acute Disease; Cell Differentiation; Cell Line, Tumor; Cholecalciferol; Core Binding Factor Alpha 2 Subunit; DNA-Binding Proteins; Gene Expression Regulation, Neoplastic; Humans; Leukemia, Myeloid; Neoplasm Proteins; Nuclear Proteins; Nuclear Receptor Co-Repressor 1; Nuclear Receptor Co-Repressor 2; Oncogene Proteins, Fusion; Peptides; Protein Structure, Tertiary; Repressor Proteins; RUNX1 Translocation Partner 1 Protein; Transcription Factors; Tretinoin

The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is regarded as a potential anticancer agent. However, many cancer cells are resistant to apoptosis induction by TRAIL. The present study was designed to evaluate the sensitivity to TRAIL-induced apoptosis in acute myeloblastic leukemias (AML).. TRAIL/TRAIL receptor (TRAIL-R) expression and sensitivity to TRAIL-mediated apoptosis were explored in 79 AML patients, including 17 patients with acute promyelocytic leukemia (APL).. In non-APL AML we observed frequent expression of TRAIL decoy receptors (TRAIL-R3 and TRAIL-R4), while TRAIL-R1 and TRAIL-R2 expression was restricted to AML exhibiting monocytic features. Total leukemic blasts, as well as AML colony-forming units (AML-CFU), were invariably resistant to TRAIL-mediated apoptosis. APL express membrane-bound TRAIL on their surface and exhibit a pattern of TRAIL-R expression similar to that observed in the other types of AML. Before, during and after retinoic acid treatment APL cells are TRAIL-resistant. The induction of granulocytic maturation of APL cells by retinoic acid was associated with a marked decline of TRAIL expression.. The analysis of experimental APL models (i.e., U937 cells engineered to express PML/RAR-Eo and NB4 cells) provided evidence that PML/RAR-Eo expression was associated with downmodulation of TRAIL-R1 and with resistance to TRAIL-mediated apoptosis. We suggest that AML blasts, including APL blasts, are resistant to TRAIL-mediated apoptosis, a phenomenon seemingly related to the expression of TRAIL decoy receptors on these cells. Finally, APL blasts express membrane-bound TRAIL that could confer an immunologic privilege to these cells.

Topics: Acute Disease; Adolescent; Adult; Antineoplastic Agents; Apoptosis; Caspase 3; Caspase 8; Cell Differentiation; Cell Membrane; Cytarabine; Drug Resistance, Neoplasm; Etoposide; Female; GPI-Linked Proteins; Granulocytes; HL-60 Cells; Humans; Hydroxyurea; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Male; Middle Aged; Monocytes; Oncogene Proteins, Fusion; Receptors, TNF-Related Apoptosis-Inducing Ligand; Receptors, Tumor Necrosis Factor; Receptors, Tumor Necrosis Factor, Member 10c; Recombinant Fusion Proteins; Tretinoin; Tumor Cells, Cultured; Tumor Necrosis Factor Decoy Receptors; Tumor Stem Cell Assay; U937 Cells

We studied wild-type FLT3 mRNA expression at diagnosis in bone marrow samples from 85 patients with acute myeloid leukemia (AML), 23 of whom were in complete remission, and determined its utility as a marker for minimal residual disease (MRD). We conclude that FLT3 expression is of limited value as a prognostic marker and for MRD monitoring.

Topics: Acute Disease; Antineoplastic Combined Chemotherapy Protocols; Biomarkers, Tumor; Bone Marrow; Combined Modality Therapy; Cytarabine; Daunorubicin; Etoposide; Female; fms-Like Tyrosine Kinase 3; Hematopoietic Stem Cell Transplantation; Humans; Leukemia, Myeloid; Male; Middle Aged; Neoplasm Proteins; Neoplasm, Residual; Prognosis; Remission Induction; RNA, Messenger; RNA, Neoplasm; Survival Analysis; Tretinoin

The retinoic acid receptor alpha (RARA) gene is disrupted by PML/RARA fusion in acute promyelocytic leukemia (APL). The P2 promoter of RARA, controlling the RARalpha2 isoform, contains an RA-responsive element and may be targeted in APL. To test whether aberrant methylation of P2 was involved, 47 APL at diagnosis, 16 APL at first relapse, 50 acute myeloid leukemia (AML) and 22 acute lymphoblastic leukemia (ALL) were tested by methylation-specific polymerase chain reaction. RARA P2 methylation was highly associated with APL (APL: 25/63 vs AML/ALL: 2/75, P<0.0001). P2 methylation occurred at similar frequencies in APL at diagnosis and relapse, suggesting it was an initiating leukemogenic event. In the APL line NB4, RARalpha2 was not expressed, with the untranslocated RARA shown to be P2 methylated. 5-Azacytadine treatment of NB4 led to progressive P2 demethylation and re-expression of RARalpha2, confirming that RARA methylation collaborated with PML/RARA in totally suppressing RARalpha. In APL, RARA P2 methylation was unrelated to gender, age, presenting leukocyte counts and additional cytogenetic aberrations. For APL patients receiving all-trans retinoic acid for induction, P2 methylation did not affect the complete remission rates and survivals. RARA is the first myeloid-specific transcription factor shown to be dysregulated by both translocation and aberrant methylation.

Topics: Acute Disease; Biological Transport; DNA Methylation; Gene Expression Regulation, Neoplastic; Humans; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Polymerase Chain Reaction; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Promoter Regions, Genetic; Receptors, Retinoic Acid; Recurrence; Remission Induction; Retinoic Acid Receptor alpha; Survival Rate; Tretinoin

Acute promyelocytic leukemia (APL) is invariably associated with chromosomal translocation to retinoic acid receptor alpha (RARalpha) locus. In a vast majority of cases, RARalpha translocates to and fuses with the promyelocytic leukemia (PML) gene. It was thought that the fusion protein PML-RARalpha acts as a double dominant negative mutant to inhibit the PML and RARalpha signaling. In an attempt to study the physiological role of retinoic acid in mammary gland development, we created a transgenic model system expressing a dominant negative RARalpha under the regulation of murine mammary tumor viral promoter. We found that the transgene was also targeted to the lymphoid system in addition to mammary gland. Here we showed that dominant negative RARalpha induced acute lymphoblastic leukemia and lymphoma development in the transgenic mice. Retinoic acid blocked tumor development ex vivo through induction of apoptosis. Thus, our results suggested that disruption of RARalpha signaling was the first essential step in the development of APL in vivo.

Topics: Acute Disease; Animals; Apoptosis; Cell Proliferation; Female; Gene Expression Regulation; Genes, Dominant; Humans; Male; Mammary Tumor Virus, Mouse; Mice; Mice, Transgenic; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Survival Rate; Tretinoin; Tumor Cells, Cultured

Treatment of acute leukaemia in adult Jehovah's Witnesses (JW) is challenging because of 'a priori' refusal of most physicians to apply diagnostic and therapeutic procedures to haematological abnormalities resembling acute leukaemia. Rejection of blood transfusions by individuals of this faith is usually blamed to justify this attitude, thus leading to severe personal, medical and psychological distress related to the lack of care. We therefore intended to verify whether a standard (tailored) chemotherapy, without the use of prophylactic blood product transfusions, could be applied during treatment of acute leukaemia under such circumstances. Eleven consecutive JW adult patients with acute leukaemia, all of whom had been denied care in other institutions, were treated at the European Institute of Oncology (EIO) in Milan, Italy. Five had acute lymphoblastic leukaemia (ALL) (one bcr/abl positive), six had acute myeloid leukaemia (AML) with immunophenotype and/or cytogenetic intermediate-high risk features, except one patient with acute promyelocytic leukaemia (APML). Standard induction chemotherapy [cytosine arabinoside (ARA-C) and daunorubicin (DNR) for AML, vincristine (VCR), DNR and prednisone (PDN) for ALL, all-trans retinoic acid (ATRA) and DNR for APML] with the antracycline dose of at least 30 mg/sqm were used. All patients experienced severe anaemia after induction chemotherapy despite erythropoietin. Median haemoglobin nadir for patients with ALL and AML was 4.5 g/dL (range 1.3-6.9) and 5.1 g/dL (range 2.6-6.8), respectively. Median platelet nadir counts for all patients was 14.5 x 10(9))/L (range 1-24). One patient died during induction probably due to haemorrhage. Four of five patients with ALL achieved a complete remission (CR) (including the bcr/abl case) while among patients with AML only the one with APML achieved CR. Three patients (APML = 1 and ALL = 2) are still alive and disease-free. This small series of adult patients with leukaemia illustrates difficulties in treating patients who are practising JW, yet nevertheless provides a significant argument against the prejudicial decision leading to evasion of treatment in these patients.

Topics: Acute Disease; Adult; Antineoplastic Combined Chemotherapy Protocols; Case Management; Cytarabine; Daunorubicin; Etoposide; Female; Hemoglobins; Hemorrhage; Humans; Jehovah's Witnesses; Leukemia; Male; Middle Aged; Multiple Organ Failure; Patient Acceptance of Health Care; Refusal to Treat; Remission Induction; Tretinoin; Vincristine

Acute leukemia patients with MLL (mixed linage leukemia) rearrangements tend to respond poorly to conventional therapies. We examined differentiation of human myeloid leukemia cells displaying the MLL-AF9 gene, using several differentiation agents. When MOLM-14 cells were treated with all-trans retinoic acid (ATRA) or 1beta,25-dihydroxyvitamin D3, significant induced differentiation was observed. Trichostatin A (TSA), an inhibitor of histone deacetylase, demonstrated enhance effects with ATRA in regard to growth inhibition and differentiation induction in MOLM-14 cells. Pretreatment with TSA before exposure to ATRA displayed increased effect. Based on these findings, combined treatment with ATRA and TSA may be clinically useful in therapy for acute leukemia displaying MLL-AF9 fusion gene.

Topics: Acute Disease; Cell Cycle Proteins; Cell Differentiation; Cell Line, Tumor; Chromosomes, Human, Pair 11; Chromosomes, Human, Pair 9; Cyclin-Dependent Kinase Inhibitor p21; Drug Synergism; Granulocytes; Humans; Hydroxamic Acids; Leukemia, Myeloid; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Translocation, Genetic; Tretinoin; Up-Regulation

Exogenous expression of the transcription factor Scl (Tal1) in WEHI-3B D+ myelomonocytic leukemia cells interferes with their capacity to respond to all-trans retinoic acid (ATRA) induced differentiation; combination of ATRA with LiCl, however, circumvents the inhibition of differentiation produced by Scl. To gain information on the possible involvement of this transcription factor in the non-responsiveness of acute myelocytic leukemia (AML) patients to ATRA, we compared the endogenous expression levels of Scl and its transcription complex partners [i.e., Rbtn1 (LMO1), Rbtn2 (LMO2), Ldb1, and GATA family proteins] in leukemic blast cells from patients with AML and acute promyelocytic leukemia (APL), and determined the effects of lithium chloride alone or in combination with ATRA on the capacity of blast cells to differentiate during short-term ex vivo culture. Levels of Scl, Rbtn2, GATA1, and Ldb1 expression were comparable in AML and APL blasts, while the levels of expression of Rbtn1, GATA2, and GATA3 were absent or markedly lower in APL cells. Differentiation markers (cell surface myeloid antigens CD11b, CD15, CD14, and CD33) were also analyzed in blast cells. ATRA produced changes in at least one surface antigen differentiation marker in 89% of patient blasts, while LiCl caused such changes in 72% of the leukemic cells of patients. The combination of LiCl and ATRA induced the differentiation of leukemic blasts from 94% of patients. Although the expression of the transcription factors did not act as individual predictors of responsiveness or non-responsiveness to the inducers of differentiation, ATRA or ATRA plus LiCl, the addition of LiCl to ATRA increased the differentiation response over that of ATRA alone in a number of leukemic samples. These findings suggest that the combination of LiCl and ATRA may produce some clinical benefit in the treatment of the myeloid leukemias.

Topics: Acute Disease; Adult; Aged; Base Sequence; Basic Helix-Loop-Helix Transcription Factors; Bone Marrow Cells; Cell Differentiation; DNA Primers; DNA-Binding Proteins; Female; Flow Cytometry; Humans; Leukemia, Myeloid; Lithium Chloride; Male; Middle Aged; Proto-Oncogene Proteins; T-Cell Acute Lymphocytic Leukemia Protein 1; Transcription Factors; Tretinoin

CCAAT/enhancer binding proteins (C/EBPs) are a family of factors that regulate cell growth and differentiation. These factors, particularly C/EBPalpha and C/EBPepsilon, have important roles in normal myelopoiesis. In addition, loss of C/EBP activity appears to have a role in the pathogenesis of myeloid disorders including acute myeloid leukemia (AML). Acute promyelocytic leukemia (APL) is a subtype of AML in which a role for C/EBPs has been postulated. In almost all cases of APL, a promyelocytic leukemia-retinoic acid receptor alpha (PML-RARalpha) fusion protein is expressed as a result of a t(15;17)(q22;q12) chromosomal translocation. PML-RARalpha inhibits expression of C/EBPepsilon, whereas all-trans retinoic acid (tRA), a differentiating agent to which APL is particularly susceptible, induces C/EBPepsilon expression. PML-RARalpha may also inhibit C/EBPalpha activity. Thus, the effects of PML-RARalpha on C/EBPs may contribute to both the development of leukemia and the unique sensitivity of APL to tRA. We tested the hypothesis that increasing the activity of C/EBPs would revert the leukemic phenotype. C/EBPalpha and C/EBPepsilon were introduced into the FDC-P1 myeloid cell line and into leukemic cells from PML-RARA transgenic mice. C/EBP factors suppressed growth and induced partial differentiation in vitro. In vivo, enhanced expression of C/EBPs prolonged survival. By using a tamoxifen-responsive version of C/EBPepsilon, we observed that C/EBPepsilon could mimic the effect of tRA, driving neutrophilic differentiation in leukemic animals. Our results support the hypothesis that induction of C/EBP activity is a critical effect of tRA in APL. Furthermore, our findings suggest that targeted modulation of C/EBP activities could provide a new approach to therapy of AML.

Topics: Acute Disease; Animals; Antineoplastic Agents; CCAAT-Enhancer-Binding Protein-alpha; CCAAT-Enhancer-Binding Proteins; Cell Differentiation; Cell Division; Humans; Leukemia, Myeloid; Mice; Mice, Transgenic; Phenotype; Transduction, Genetic; Tretinoin; Tumor Cells, Cultured

The nuclear receptor ligand all-trans retinoic acid (ATRA) causes dramatic terminal differentiation of acute promyelocytic leukemia (APL) cells in vitro and in patients, but it is less active in other malignancies. However, downstream mediators of the effects of ATRA are not well understood. We used a cDNA microarray to search for ATRA-regulated genes in the APL cell line NB4 and found that ATRA regulated several members of the tumor necrosis factor (TNF) pathway. Here we show that TNF can synergize with ATRA to induce differentiation, showing monocytic characteristics more typical of differentiation mediated by TNF than by ATRA. ATRA and TNF can also induce differentiation of the non-APL cell line U937. Underlying this response was an increase in TNF-induced nuclear factor-kappaB (NF-kappaB) DNA binding within 2 hours in the presence of ATRA and activation of NF-kappaB DNA binding and transcriptional activity in response to ATRA alone within 48 hours of ATRA treatment. Furthermore, we found a synergistic induction of the NF-kappaB target genes BCL-3, Dif-2, and TNF receptor 2 (TNFR2) in response to the combination of TNF and ATRA. These genes have been previously shown to play a role in TNF signaling, and amplification of such genes may represent a mechanism whereby TNF and ATRA can act synergistically. We propose that ATRA can prime cancer cells for differentiation triggered by TNF and suggest that targeting the TNF pathway in combination with ATRA may represent a novel route to treat leukemias.

Topics: Acute Disease; Apoptosis; Cell Differentiation; DNA; Drug Synergism; Gene Expression Regulation, Leukemic; Humans; Leukemia; NF-kappa B; Transcription, Genetic; Tretinoin; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha

Topics: Acute Disease; Adult; Antineoplastic Combined Chemotherapy Protocols; Chromosomes, Human, Pair 11; Chromosomes, Human, Pair 9; Female; Humans; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Neoplasms, Second Primary; Translocation, Genetic; Tretinoin

Topics: Acute Disease; Blood Coagulation; Hemorrhage; Humans; Leukemia; Tretinoin

Neutrophil homeostasis was investigated in two mouse lines, AIRmax and AIRmin, genetically selected for high or low acute inflammatory response (AIR) and compared with unselected BALB/c mice. Mature neutrophil phenotype and functions appeared similar in the three mouse lines. However, an unprecedented phenotype was revealed in AIRmax animals characterized by a high neutrophil production in bone marrow (BM), a high number of neutrophils in blood, a high concentration of chemotactic agents in acrylamide-induced inflammatory exudates, and an increased resistance of locally infiltrated neutrophils to spontaneous apoptosis. In vitro, BM production of neutrophils and eosinophils was accompanied by an unusual high up-regulation of cytokine receptors as assessed by antibodies to CD131, which bind the common beta chain of receptors to interleukin (IL)-3, IL-5, and granulocyte macrophage-colony stimulating factor. An accelerated neutrophil maturation was also observed in response to all-trans retinoic acid. Several candidate genes can be proposed to explain this phenotype. Yet, more importantly, the results underline that genetic selection, based on the degree of AIR and starting from a founding population resulting from the intercross of eight inbred mouse lines, which display a continuous range of inflammatory responses, can lead to the convergent selection of alleles affecting neutrophil homeostasis. Similar gene combinations may occur in the human with important consequences in the susceptibility to inflammatory or infectious diseases and cancer.

Topics: Acute Disease; Apoptosis; Bone Marrow Cells; Cell Differentiation; Chemotaxis, Leukocyte; Granulocyte-Macrophage Colony-Stimulating Factor; Hematopoiesis; Inflammation; Leukocyte Count; Neutrophils; Platelet Endothelial Cell Adhesion Molecule-1; Tretinoin

Topics: Acute Disease; Adult; Dermatologic Agents; Female; Graft vs Host Disease; Hematopoietic Stem Cell Transplantation; Humans; Keratosis; Leukemia, Myeloid; Nipples; Treatment Outcome; Tretinoin

Interactions between hemopoietic cells and the stromal microenvironment or immunoreactive cells are mediated by specific cell surface receptors. The expression of those molecules may alter the adhesive qualities (mobility and homing) as well as immune response behavior of leukemic blasts. L-Selectin (CD62L) is suggested to play a role in the redistribution and homing of hemopoietic progenitor cells to the bone marrow (BM). Down-regulation of L-selectin is responsible for mobilization of blasts from the BM into the circulation and ligation of L-selectin stimulates proliferation of progenitor cells. This could have an influence on the process of leukemia.. We have studied the expression of L-selectin on mononuclear BM cells of 36 acute myeloid leukemia (AML) patients at first diagnosis by FACS analysis using a directly fluorescein isothiocyanate conjugated antibody (clone DRE G56).. On average the patients presented with 88% blasts in the BM. The expression tended to be higher in primary (p) AML compared with secondary (s) AML. L-Selectin was very heterogenously expressed in all FAB groups. Highest expression was found in cases with AML-M4 with four of nine cases presenting with an inv(16) karyotype. Separating our patient cohort in cytogenetic risk groups we could detect a significantly higher expression of L-selectin in cases with a 'good risk' karyotype and a very low expression in cases with a 'bad risk' karyotype (P = 0.037). Comparing patients who achieved remission after double induction therapy (responders) with patients who showed persisting disease (non-responders) we found a higher percentage of L-selectin+ cases or cells in the responder group than in the non-responder group, although the differences were not significant because of only five cases in the 'non-responder' group. Evaluating cut-off points greatest differences in relapse-free survival probabilities were found in patients who presented with > or = 30% L-selectin+ BM cells compared with cases with < 30%: 86% of cases with > or = 30% L-selectin+ cells were still in remission after a mean follow up time of only 8 months compared with only 46% in the group with < 30% L-selectin+ cells.. We can conclude that (i) expression of L-selectin on AML blasts is variable. This reveals the great diversitiy of immunophenotypes in AML and might contribute to identify individual blast phenotypes in order to detect minimal residual disease in remission. (ii) Low L-selectin expression correlates with a bad cytogenetic risk, with a lower probability to achieve remission and with a shorter relapse-free survival time. This might reflect a decreased homing of the blasts to the BM as well as an impaired cytotoxic T-cell reaction against leukemic cells. The expression of L-selectin on leukemic blasts might be influenced by different cytokine therapies (e.g. with interferon alpha) and this might result in an altered hematologic reconstitution after cytotoxic therapies as well as in an altered immunologic recognition of blasts.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Bone Marrow Cells; Chromosome Aberrations; Cytarabine; Daunorubicin; Disease-Free Survival; Female; Humans; L-Selectin; Leukemia, Myeloid; Male; Middle Aged; Mitoxantrone; Neoplasm Proteins; Neoplastic Stem Cells; Remission Induction; Risk; Thioguanine; Treatment Outcome; Tretinoin

In acute myeloid leukaemia (AML), cell kinetic quiescence has been postulated to contribute to drug resistance. As the anti-apoptotic genes Bcl-2 and Bcl-X(L) have been implicated in cell cycle regulation, we investigated the expression of these genes in non-proliferating (Q) and proliferating (P) AML and normal CD34+ progenitor cells. Using reverse transcription polymerase chain reaction, Bcl-X(L) and Bcl-2 were overexpressed in Q versus P AML cells, whereas no difference in Bcl-XS and Bax expression was found. Furthermore, the Bcl-X(L)/X(S) but not the Bcl-2/Bax ratio was higher in Q AML compared with normal CD34+ Q cells (P = 0.001). An inverse correlation between Bcl-2 expression of leukaemic Q cells and their ability to enter the cell cycle was found. Treatment with all-trans retinoic acid (ATRA) reduced Bcl-2 and Bcl-X(L) expression in the leukaemic Q cells, and enhanced their chemosensitivity to cytosine arabinoside (ara-C). These findings demonstrate overexpression of the anti-apoptotic proteins Bcl-X(L) and Bcl-2 in quiescent CD34+ AML cells and suggest their involvement in the chemoresistance. The observed inverse correlation between Bcl-2 and proliferation suggests a role for Bcl-2 in the cell cycle regulation of AML. These findings could be used in the development of therapies that selectively induce apoptosis in quiescent leukaemic progenitor cells.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Antigens, CD34; Antimetabolites, Antineoplastic; Antineoplastic Agents; Apoptosis; bcl-X Protein; beta 2-Microglobulin; Bone Marrow Cells; Cell Division; Cytarabine; Down-Regulation; fas Receptor; Flow Cytometry; Genes, bcl-2; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid; Middle Aged; Proto-Oncogene Proteins c-bcl-2; Tretinoin

An exploratory trial was conducted to evaluate toxicity and potential therapeutic role of all trans-retinoic acid (ATRA) given long-term together with chemotherapy and G-CSF to adult patients with acute myelogenous leukemia (AML).. ATRA was administered orally at 45 mg/m(2)/day on days 1-14 and 25 mg/m(2)/day on days 15-28 of two standard cycles (idarubicin, etoposide, cytarabine, G-CSF) and of up to three high-dose courses (cytarabine, G-CSF). The results obtained in 19 patients enrolled in the ATRA trial were compared with those from 29 comparable cases treated with the same schedule without ATRA, according to patient risk class and an in vitro study.. ATRA was administered for a median of 52 days to the patients selected for study who achieved a remission. ATRA-related toxicity was mostly non-severe apart from high incidence of headache in conjunction with high-dose cytarabine. Complete remission (CR) rate after cycle 1 (54%), kinetics of hematological recovery, postremission treatment realization, disease-free survival (DFS 37.5% at three years) and overall survival (30% at three years) were not different between ATRA-treated and untreated patients. The only significant prognostic factor was the patient risk class, as defined by cytogenetics and other clinical criteria: DFS rate was 57% at three years in standard-risk cases compared to only 19% in the high-risk group, with no influx by ATRA in either category. The in vitro study, in patients with a definite clinical response, failed to document any inhibitory or pro-apoptotic effect of ATRA on AML blast cells.. As a consequence to these results, the pilot ATRA phase was closed. This study does not suggest a significant role for the present ATRA schedule as an adjunct to standard antileukemic therapy in adult AML.

Topics: Acute Disease; Adolescent; Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Cytarabine; Disease-Free Survival; Etoposide; Female; Filgrastim; Granulocyte Colony-Stimulating Factor; Headache; Humans; Idarubicin; Leukemia, Myeloid; Life Tables; Male; Middle Aged; Neoplastic Stem Cells; Patient Compliance; Pilot Projects; Recombinant Proteins; Remission Induction; Survival Analysis; Treatment Failure; Tretinoin

Alterations in the FLT3 gene, including internal tandem duplications (ITDs) and D835 mutations occur frequently in acute myelogenous leukemia. We investigated the prevalence and clinico-biological correlations of FLT3 ITDs and D835 mutations in 90 patients with acute promyelocytic leukemia (APL) receiving the AIDA protocol. Twenty patients in which both presentation and relapse material was available were analyzed sequentially. Thirty-three patients (37%) harbored the ITD, and seven (7.7%) the D835 mutation in blasts obtained at diagnosis. Presence of ITDs was strongly associated with high WBC count (P = 0.0001), M3 variant (P = 0.0004), and the short (BCR3) PML/RARalpha isoform (P = 0.003). There was no difference in response to induction in the two ITD+ve and ITD-ve groups, while a trend towards inferior outcome was observed for ITD+ve cases when analyzing disease-free survival (DFS) and relapse risk (RR). These differences, however, did not reach statistical significance. Sequential studies showed variable patterns in diagnostic and relapse material, ie ITD (-ve/-ve, +ve/+ve, +ve/-ve, -ve/+ve) and D835 (-ve/-ve, +ve/-ve, -ve/+ve). Our results indicate that FLT3 alterations are associated in APL with more aggressive clinical features and suggest that these lesions may not play a major role in leukemia progression.

Topics: Acute Disease; Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; DNA Primers; DNA, Neoplasm; Female; fms-Like Tyrosine Kinase 3; Hemoglobins; Humans; Idarubicin; Leukemia, Promyelocytic, Acute; Leukocyte Count; Male; Middle Aged; Mutation; Neoplasm Proteins; Oncogene Proteins, Fusion; Platelet Count; Proto-Oncogene Proteins; Receptor Protein-Tyrosine Kinases; Reverse Transcriptase Polymerase Chain Reaction; Risk Factors; RNA, Messenger; RNA, Neoplasm; Tandem Repeat Sequences; Treatment Outcome; Tretinoin

PTPases are key signaling molecules and targets for developing novel therapeutics. We have studied the in vitro biological activity of PTPase inhibitor sodium stibogluconate (SS) on differentiation and proliferation of myeloid leukemia cell lines (NB4, HL-60 and U937). SS (250 microg/ml, 6 days) induced 87% of NB4 cells to reduce nitroblue tetrazolium (NBT), in comparison to the 90% induced by ATRA (1 microM, 6 days). SS treatment of NB4 cells resulted in an increase of CD11b expression and of a morphologically more mature population, coincident with growth arrest at S phase and increased cell death. The effect of SS on NB4 differentiation was irreversible and required continuous drug exposure. SS (400 microg/ml, 6 days) induced 60% and 55% of NBT-positive cells in HL-60 and U937 cell lines, which were augmented in the presence of GM-CSF (25 ng/ml) to levels (85% and 81%, respectively) comparable to those induced by ATRA. SS induced increased tyrosine phosphorylation of cellular proteins in the AML cell lines and inactivated SHP-1 PTPase in NB4 cells, consistent with SS functioning as a PTPase inhibitor in the leukemia cells. These results provide the first evidence of an anti-leukemia activity of SS as a PTPase inhibitor.

Topics: Acute Disease; Antimony Sodium Gluconate; Antineoplastic Agents; Antiprotozoal Agents; Cell Cycle; Cell Differentiation; Cell Division; Gene Expression Regulation, Leukemic; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Intracellular Signaling Peptides and Proteins; Leukemia, Myeloid; Nitroblue Tetrazolium; Oxidation-Reduction; Phosphorylation; Protein Tyrosine Phosphatase, Non-Receptor Type 6; Protein Tyrosine Phosphatases; Tretinoin; Tumor Cells, Cultured; Tyrosine

All-trans retinoic acid (ATRA) is used in the treatment of acute promyelocytic leukemia. Because ATRA has effects (increase in apoptosis, suppression of bcl-2), it has also been used for the treatment of other French-American-British (FAB) subtypes of acute myelogenous leukemia (AML). To find out the in vivo and in vitro effects of ATRA in AML, we analyzed 37 patients with de novo AML. Twenty-seven patients received ATRA before remission-induction (RI) treatment (ATRA group). Results were compared to a control group (10 patients) that received induction without ATRA during the same time period. Bone marrow or peripheral blood samples were collected from all patients on d 0 and 4. The immunphenotype, myeloperoxidase (MPO), reac tion and the efflux uptake of rhodamine 123 (Rh123) were analyzed on myeloblasts in these samples. In the myeloblasts from patients treated with ATRA, the uptake of Rh123 was increased significantly (p = 0.026) from d 0 to d 4, and all other parameters remained unaltered. ATRA administration increased the complete remission (CR) rate (88%, 22/25 vs 55%, 5/9) significantly (p = 0.042). Logistic regression analysis revealed that ATRA administration was the important factor in CR, among other potential factors including age, white blood count, bcl-2 expression, and the uptake and efflux of Rh123 (p = 0.05). Estimated disease-free survival and overall survival were similar between these two groups (43% vs 37.5% and 51.2% vs 37.5%, respectively). In conclusion, ATRA treatment prior to RI treatment may improve the CR rate in patients with de novo AML, which seems to be related to its beneficial effect on multidrug resistance.

Topics: Acute Disease; Adolescent; Adult; Aged; Antigens, CD; Antimetabolites, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Biomarkers, Tumor; Case-Control Studies; Cytarabine; Drug Resistance, Multiple; Etoposide; Female; Fluorescent Dyes; Humans; Idarubicin; Immunophenotyping; Leukemia, Myeloid; Leukocyte Count; Male; Middle Aged; Proto-Oncogene Proteins c-bcl-2; Remission Induction; Rhodamine 123; Treatment Outcome; Tretinoin

In this study, we have investigated the expression of phospholipase C-beta2 during the course of granulocytic differentiation of normal and malignant progenitors. As a model system, we used the NB4 cell line, a reliable in vitro model for the study of acute promyelocytic leukemia (APL), a variety of acute myeloid leukemia (AML) that responds to pharmacological doses of all trans-retinoic acid (ATRA) by differentiating in a neutrophil-like manner. We found that PLC-beta2, virtually absent in untreated NB4 cells, was strongly up-regulated after ATRA-induced granulocytic differentiation. Remarkably, using primary blasts purified from bone marrow of patients affected by APL successfully induced to remission by treatment with ATRA, we showed a striking correlation between the amount of PLC-beta2 expression and the responsiveness of APL blasts to the differentiative activity of ATRA. An increase of PLC-beta2 expression also characterized the cytokine-induced granulocytic differentiation of CD34+ normal hematopoietic progenitors. Taken together, these data show that PLC-beta2 represents a sensitive and reliable marker of neutrophil maturation of normal and malignant myeloid progenitors. Moreover, PLC-beta2 levels can predict the in vivo responsiveness to ATRA of APL patients.

Topics: Acute Disease; Antigens, CD; Antigens, CD34; Cell Differentiation; Enzyme Inhibitors; Estrenes; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; Granulocyte Colony-Stimulating Factor; Granulocytes; Hematopoietic Stem Cells; Humans; Interleukin-3; Isoenzymes; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Phospholipase C beta; Protein Isoforms; Pyrrolidinones; Tretinoin; Tumor Cells, Cultured; Type C Phospholipases

To clarify the characteristics of de novo acute myeloid leukemia (AML) among the elderly, we reviewed 112 patients over 60 years old (median age 72 years) who were treated at hospitals in Nagasaki Prefecture with a population of 1.5 million between 1987 and 1994. Reclassification of morphological diagnosis revealed that the proportion of M3 was lower but that of M6 and the incidence of cases with trilineage dysplasia (TLD), known as poor prognostic features, were higher in the elderly than in patients less than 60 years old. Similarly, chromosomal data showed a lower frequency of favorable karyotypes such as t(8;21) and t(15;17) in the elderly. The overall survival of all 112 patients was 10.3% at 5 years. Multivariate analysis indicated that good performance status (PS), low WBC at diagnosis, standard dose multi-drug chemotherapy and all-trans retinoic acid (ATRA) treatment for M3 patients, and morphological findings without TLD were significantly correlated with longer survival. Most of the long-term survivors were found among those who received standard dose therapy in this series, although no consensus has been established how to treat elderly AML patients. We propose that a prospective controlled trial is necessary to confirm the role of standard dose chemotherapy for elderly patients with de novo AML.

Topics: Acute Disease; Aged; Aged, 80 and over; Aging; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Daunorubicin; Female; Humans; Karyotyping; Leukemia, Myeloid; Male; Mercaptopurine; Middle Aged; Prognosis; Treatment Outcome; Tretinoin

Cotylenin A, which has a diterpenoid tricarbocyclic skeleton, has been isolated as a plant growth regulator, has been shown to affect several physiological processes of higher plants and have differentiation-inducing activity in several myeloid leukaemia cell lines. We examined the effect of cotylenin A on the differentiation of leukaemic cells that were freshly isolated from acute myeloid leukaemia (AML) patients in primary culture. Cotylenin A significantly stimulated both functional and morphological differentiation of leukaemia cells in 9 out of 12 cases. This differentiation-inducing activity was more potent than those of all-trans retinoic acid and 1alpha,25-dihydroxyvitamin D3 (VD3). Treatment with a combination of cotylenin A and VD3 was more effective than cotylenin A or VD3 alone at inducing the monocytic differentiation of AML cells.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Antigens, CD; Antigens, Differentiation, T-Lymphocyte; Calcitriol; Cell Differentiation; Diterpenes; Drug Synergism; Female; Humans; Lectins, C-Type; Leukemia, Myeloid; Lipopolysaccharide Receptors; Macrophage-1 Antigen; Male; Middle Aged; Plant Growth Regulators; Statistics, Nonparametric; Tretinoin; Tumor Cells, Cultured

The differentiation-inducing effect of clinically applicable analogs of deoxyadenosine on myelomonocytic leukemia cells was examined. Monocytoid leukemia cells were more sensitive to the analogs than were erythroid or myeloid leukemia cells based on the inhibition of cell growth and induction of cell differentiation. Monocytoid leukemia cells were highly sensitive to combined treatment with 2'-deoxycoformycin (dCF) and 9-beta-D-arabinofuranosyladenine (Ara A) for inducing cell differentiation. Ara A induced the differentiation of monocytoid leukemia U937 and THP-1 cells at concentrations which were 1/1000-10000 of that at which it induced the differentiation of other cell lines in the presence of dCF. In combination with a low concentration of 1alpha,25-dihydroxyvitamin D3 (VD3), the induction of the monocytic differentiation was greater in monoblastic U937 cells. Adenosine deaminase-resistant analogs such as fludarabine (FLU) and cladribine (CdA) also induced the differentiation of human myelomonocytic leukemia cells, and these analogs synergistically enhanced the differentiation induced by all-trans retinoic acid (ATRA) or VD3. CdA was the most potent analog for inducing the differentiation of myeloid leukemia NB4 and HL-60 cells in the presence or absence of ATRA. These findings indicate that dCF + Ara A and CdA may be effective for the therapy of acute monocytoid and myeloid leukemia, respectively.

Topics: Acute Disease; Adenosine Deaminase Inhibitors; Antimetabolites, Antineoplastic; Calcitriol; Cell Differentiation; Cladribine; Deoxyadenosines; Dose-Response Relationship, Drug; Drug Synergism; Enzyme Inhibitors; HL-60 Cells; Humans; K562 Cells; Leukemia, Myeloid; Monocytes; Neoplasm Proteins; Neoplastic Stem Cells; Pentostatin; Tretinoin; Tumor Cells, Cultured; U937 Cells; Vidarabine

All-trans retinoic acid (ATRA) induces complete remission in acute promyelocytic leukemia (APL or M3). In this study we measured the effect of retinoids alone and in combination with daunorubicin (DNR) on cell growth and apoptosis in blast cells from patients with non-M3 AML. Cells from 21 patients were incubated in 0.2 microM daunorubicin for 1 h or in 1 microM ATRA or 9-cis-RA continuously and in the combinations of DNR with both retinoids. Cell toxicity and apoptosis were analyzed after 96 h. Both ATRA and 9-cis-RA reduced the viability significantly to 86 and 84%, respectively (P = 0.003 for ATRA and 0.02 for 9-cis-RA). The expression of CD34 correlated to a higher sensitivity to ATRA (P = 0.003). When retinoids were added to DNR the mean decrease in viability was 11 percentage points with ATRA (P = 0.003) and nine percentage points with 9-cis-RA (P = 0.02). Apoptosis was induced by both retinoids and the percentage of apoptotic cells was increased from 16% in the controls to 24% with ATRA (P = 0.03) and to 26% with 9-cis-RA (P = 0.04). When the retinoids were added to DNR the apoptotic rate increased from 41% with DNR alone to 51% with ATRA (P = 0.01) and to 49% with 9-cis-RA (P = 0.03). We conclude that ATRA and RA exert a slight but clear cytotoxic and apoptotic effect on AML blast cells after 96 h incubation and that retinoids can have an additive or synergistic effects on cell toxicity when added to daunorubicin.

Topics: Acute Disease; Adenosine Triphosphate; Adult; Aged; Aged, 80 and over; Alitretinoin; Antibiotics, Antineoplastic; Antigens, CD34; Antineoplastic Agents; Apoptosis; Daunorubicin; Drug Synergism; Female; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid; Male; Middle Aged; Neoplastic Stem Cells; Tretinoin; Tumor Cells, Cultured

Retinoic acid has the ability to induce differentiation in some myeloid leukaemia cell lines and has been used to induce remission in acute promyelocytic leukaemia patients. We have analysed changes in gene expression, by differential display, in HL60 cells exposed to all-trans retinoic acid (ATRA) for only 1 h. Only about 0.4% of the genes examined by this technique showed changes in expression level, and all four of the gene fragments identified were downregulated during the short 1 h exposure. Two of the fragments were novel, a third was MYC and the fourth was the FUS proto-oncogene. Northern analysis showed that FUS was downregulated within 1 h only during induced neutrophil differentiation but not at all during induced monocyte differentiation. Unlike the sensitive cell lines, ATRA-resistant cell lines did not show a downregulation of FUS over a 24 h period of exposure to ATRA. Using a semiquantitative PCR analysis, no difference in FUS levels was observed between ATRA-sensitive and -resistant cell lines. A similar analysis was carried out on primary acute myeloid leukaemia (AML), peripheral stem cell harvests (PBSC) and cord blood samples. The PBSC and cord blood samples had FUS levels that were similar or generally less than the cell lines. However, much higher levels were seen in 63% of the AML samples examined. The data presented are consistent with previous reports for a role for FUS in the promotion and maintenance of cellular proliferation.

Topics: Acute Disease; Cell Differentiation; Heterogeneous-Nuclear Ribonucleoproteins; HL-60 Cells; Humans; Leukemia, Myeloid; Proto-Oncogene Mas; Ribonucleoproteins; RNA-Binding Protein FUS; Tretinoin

Topics: Acute Disease; Aged; Antineoplastic Agents; Female; Fever; Humans; Leukemia, Myeloid; Respiratory Distress Syndrome; Tretinoin

Alterations in the response of leukaemic cells to apoptosis-inducing stimuli may account for resistance to chemotherapy and treatment failure, either by disruption of the apoptotic pathway itself or by altered DNA repair; quiescent cells and those with disrupted cell-cycle checkpoints may also display decreased apoptosis. Quiescence can be induced by the differentiation of myeloid cells, and this led us to investigate whether the modulation of drug-induced apoptosis associated with differentiation might be a model for quiescence-associated resistance generally. We have demonstrated that resistance to idarubicin-induced apoptosis increased with greater duration of incubation of HL60 and U937 cells with ATRA and 1,25(OH)2 D3 and that this protective effect correlated with the degree of G0/G1 accumulation. In addition, the cytoprotective effects held for other classes of cytotoxic drugs with different mechanisms of action to idarubicin. Prolonged exposure to idarubicin or vinblastine was associated with diminution of the protective effect and re-entry of cells into cycle. The full cytoprotective effect was restored by resupplementation with ATRA or 1,25(OH)2 D3 during exposure to idarubicin, with concomitant persistence of G0/G1 accumulation. Differentiating agents prevented the accumulation of leukaemic cells at the G2/M checkpoint in response to low concentrations of idarubicin. Understanding how differentiating agents modulate these cell-cycle checkpoints, and how quiescent cells evade apoptosis, may allow the development of therapeutic strategies to limit such apoptosis-inhibiting effects and maximise cell kill from chemotherapy.

Topics: Acute Disease; Apoptosis; Calcitriol; Cell Cycle; Cell Differentiation; Dose-Response Relationship, Drug; Drug Resistance, Neoplasm; G1 Phase; HL-60 Cells; Humans; Idarubicin; Leukemia, Myeloid; Neoplastic Stem Cells; Resting Phase, Cell Cycle; Tretinoin; U937 Cells; Vinblastine

Topics: Acute Disease; Adult; Bilirubin; Hepatomegaly; Humans; Leukemia, Promyelocytic, Acute; Male; Renal Insufficiency; Transaminases; Tretinoin

The role of the p53 pathway in apoptosis induced by all-trans-retinoic acid (ATRA) was studied in 5 human acute myeloid leukaemia (AML) cell lines, OU-AML-3, -4, -5, -7 and -8, previously established and characterized by the authors. Although all the cell lines have a wild-type (wt) p53 gene, the protein is in a mutant conformation detectable by the anti-p53 antibody PAb 240. Exposure of the cell lines to 1.0 microM ATRA for 72 h caused induction of apoptosis detectable by morphology and the annexin V assay. The number of apoptotic cells according to the annexin V assay varied from 16 +/- 8% (OU-AML-7) to 61 +/- 4% (OU-AML-3) in ATRA-treated cells, while it was 7 +/- 6% in control cells. Western blotting and flow cytometry showed down-regulation of the p53 protein by ATRA. The conformation of p53 remained unchanged, being detectable in flow cytometry by PAb 240, but not by PAb 1620 (an antibody which only detects p53 in wt conformation). At the same time bcl-2 was down-regulated as shown by Western blotting and flow cytometry, while no induction of bax was observed by ATRA. On the basis of these results, ATRA-induced apoptosis in these AML cell lines is independent of the p53 pathway, although it is associated with the down-regulation of bcl-2.

Topics: Acute Disease; Apoptosis; bcl-2-Associated X Protein; Blotting, Western; Flow Cytometry; Gene Expression Regulation, Leukemic; Genes, bcl-2; Genes, p53; Humans; Leukemia, Myeloid; Neoplasm Proteins; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-bcl-2; Tretinoin; Tumor Cells, Cultured; Tumor Suppressor Protein p53

Histone deacetylase inhibitors (HDACIs) have been used to focus on the effects of inducing gene expression through the acetylation of histones which results in chromatin remodeling. The study explored whether HDACIs could induce the expression of costimulatory/adhesion molecules on acute myeloid leukemia (AML) cells, thereby effectively inducing tumor immunity. The expression of CD80, CD86, human leukocyte antigen (HLA)-DR, HLA-ABC, and intracellular adhesion molecule-1 (ICAM-1) was tested in human AML cell lines after the addition of HDACI, sodium butyrate (SB). Generally, increased expression of CD86 was observed by SB treatment in a majority of cell lines, and ICAM-1 was expressed in fewer cell lines. Essentially the same results were obtained using other HDACIs such as FR901228, trichostatin A, and trapoxin A. Quantitation of transcripts of CD86 accompanied with RNA synthesis inhibition assay and nuclear run-on assay revealed that SB up-regulates the CD86 expression transcriptionally. Furthermore, chromatin immunoprecipitation experiments showed that HDACI treatment caused remarkable acetylation on histone H3 and H4 at CD86 promoter chromatin in vivo. In 30 clinical AML samples, CD86 expression was significantly increased (P <.001) by SB treatment, and the expression of HLA-DR and ICAM-1 was moderately increased (P <.05) by SB treatment. Finally, the allogeneic mixed leukocyte reaction (allo-MLR) against HL60 cells pretreated with SB was enhanced 4-fold compared with allo-MLR obtained with non-treated HL60 cells. These results suggest that the immunotherapeutic use of HDACIs may become a novel tool for treatment of AML. (Blood. 2000;96:3847-3856)

Topics: Acetylation; Acute Disease; Antigens, CD; B7-2 Antigen; Butyric Acid; Cell Adhesion Molecules; Cell Differentiation; Chromatin; Enzyme Inhibitors; Histone Deacetylase Inhibitors; Histones; Humans; Immunophenotyping; Intercellular Adhesion Molecule-1; Interferon-gamma; Leukemia, Myeloid; Lymphocyte Culture Test, Mixed; Membrane Glycoproteins; Promoter Regions, Genetic; RNA, Messenger; Transcription, Genetic; Tretinoin; Tumor Cells, Cultured; Up-Regulation

We report a case in which treatment with all-trans-retinoic acid (ATRA) improved the clinical features of a 47-year-old female patient with acute adult T-cell leukemia (ATL). The patient was first treated several times with combination chemotherapy. but the number of ATL cells increased and other clinical manifestations progressed. ATRA 60 mg was then administered daily. ATRA treatment dramatically improved the patient's clinical features. In vitro examination revealed that ATRA inhibited the growth of ATL cells from the patient. These findings suggest that ATRA may be a useful treatment for patients with chemotherapy-resistant acute ATL.

Topics: Acute Disease; Antineoplastic Agents; Drug Resistance, Neoplasm; Female; Humans; Leukemia, T-Cell; Middle Aged; Tretinoin

Blockage in myeloid differentiation characterizes acute myeloid leukemia (AML); the stage of the blockage defines distinct AML subtypes (AML1/2 to AML5). Differentiation therapy in AML has recently raised interest because the survival of AML3 patients has been greatly improved using the differentiating agent retinoic acid. However, this molecule is ineffective in other AML subtypes. The CD44 surface antigen, on leukemic blasts from most AML patients, is involved in myeloid differentiation. Here, we report that ligation of CD44 with specific anti-CD44 monoclonal antibodies or with hyaluronan, its natural ligand, can reverse myeloid differentiation blockage in AML1/2 to AML5 subtypes. The differentiation of AML blasts was evidenced by the ability to produce oxidative bursts, the expression of lineage antigens and cytological modifications, all specific to normal differentiated myeloid cells. These results indicate new possibilities for the development of CD44-targeted differentiation therapy in the AML1/2 to AML5 subtypes.

Topics: Acute Disease; Antibodies, Monoclonal; Bone Marrow; Cell Differentiation; Dose-Response Relationship, Drug; Granulocyte Colony-Stimulating Factor; Granulocytes; Humans; Hyaluronan Receptors; Hyaluronic Acid; Leukemia, Myeloid; Lewis X Antigen; Lipopolysaccharide Receptors; Macrophage Colony-Stimulating Factor; Monocytes; Neoplasm Proteins; Oncogene Proteins, Fusion; Respiratory Burst; RNA, Messenger; Tretinoin; Tumor Cells, Cultured

Lodgement, proliferation, and migration of leukemic cells within bone marrow (BM) microenvironment involves adhesion of these cells to the BM extracellular matrix molecules fibronectin and laminin. The 67-kDa laminin receptor (67LR) is a nonintegrin protein with high affinity for laminin, which plays a critical role in basement membrane invasion and metastasis of cancer cells. By Western blotting, we documented that 67LR was strongly expressed in myelomonocytic THP1 and histiocytic U937 cells and was weakly expressed in promyelocytic HL-60 cells. In HL-60 cells, 67LR expression almost disappeared after retinoic-induced granulocytic differentiation, whereas it strongly increased after phorbol ester-induced monocytic differentiation. We did not detect 67LR expression in normal BM hematopoietic cells, in precursor-B acute lymphoblastic leukemia, in chronic lymphocytic leukemia, or in chronic myeloid leukemia in chronic phase. By contrast, we detected enhanced 67LR expression in 40% of 53 de novo acute myeloid leukemias (AMLs), which frequently exhibited monocytic or myelomonocytic morphology and expressed CD14 and CD11a (P < 0.05). Using a colorimetric assay, we found that the expression pattern of this receptor corresponded to a higher adhesion to laminin; the adhesion was specific because in vitro addition to laminin-coated wells of recombinant 37-kDa laminin receptor precursor (37LRP), which is the cytoplasmic precursor containing both laminin-binding domains of cell surface 67LR, significantly reduced laminin binding of AML cells. The expression of 67LR on AML cell surface did not correlate with other differentiation and integrin antigens such as CD7, CD13, CD33, CD34, CD11b, CD11c, CD49d, CD49e, CD45RA, and CD45RO. In contrast with 67LR behavior in solid tumors, no statistically significant difference was found between 67LR expression and any hematological characteristic of the disease at diagnosis, nor between 67LR expression and outcome of the disease as measured by complete remission rate, disease-free survival, or overall survival. In conclusion, our results indicate that 67LR expression mediates specific adhesion to laminin and that the detection of this molecule may be a valuable addition to other lineage-associated antigens in identifying monocytic-oriented AML.

Topics: Acute Disease; Adolescent; Adult; Aged; Antigens, CD; Blotting, Western; Cell Adhesion; Cell Differentiation; Cells, Cultured; Female; HL-60 Cells; Humans; Immunophenotyping; Laminin; Leukemia, Myeloid; Male; Middle Aged; Monocytes; Prognosis; Receptors, Laminin; Survival Rate; Tetradecanoylphorbol Acetate; Tretinoin

We have shown previously that granulocytic maturation and differentiation occurred when HL-60 cells and leukemia cells from a patient with acute promyelocytic leukemia (APL) were exposed to all-trans retinoic acid (ATRA) after treatment with a noncytotoxic concentration of vincristine (VCR), suggesting that VCR might have synergistic action with ATRA in the treatment of APL. Leukemic cells obtained from 24 patients with AML were exposed to 20 nM VCR for 1 h, followed by 1 microM ATRA for 6 days. Changes in the expression of myeloid leukocyte antigens were observed using flow cytometry. Differentiation phenotype as determined by the decrease or increase in maturation cell marker was observed in three samples treated with VCR alone, four samples treated with RA alone, and two samples treated with the combination of VCR and RA. The results suggest that treatment using VCR and ATRA may be effective in the differentiation therapy of AML.

Topics: Acute Disease; Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Cell Differentiation; Flow Cytometry; Gene Expression; HL-60 Cells; HLA Antigens; Humans; Leukemia, Myeloid; Middle Aged; Phenotype; Tretinoin; Tumor Cells, Cultured; Vincristine

P39/Tsugane is a myelomonocytoid cell line derived from a patient with myelodysplastic syndrome (MDS). The cells readily undergo apoptosis in response to various agents, and the cell line has been suggested as a useful model to study apoptosis in MDS. The aims of the present study were to assess differentiation and apoptosis induced with all-trans retinoic acid (ATRA) and etoposide, to characterize the mode of apoptosis in these two model systems, and to assess the influence of granulocyte colony-stimulating factor (G-CSF), which in combination with erythropoietin has been shown to inhibit apoptosis in MDS. ATRA induced differentiation and apoptosis in a concentration- and time-dependent manner. Differentiated cells were partially rescued (by 50%) from apoptosis with G-CSF. Etoposide induced apoptosis in a concentration- and time-dependent manner, but no signs of preceding maturation or G-CSF rescue were detected. ATRA- and etoposide-induced apoptosis were both mediated through the caspase pathway and were partially blocked with the general caspase inhibitor zVAD-fmk. Simultaneous treatment with G-CSF and zVAD-fmk additively blocked ATRA-induced apoptosis. However, the two pathways differed in terms of substrate cleavage during apoptosis. ATRA-induced apoptosis caused actin cleavage, which was not affected by G-CSF, and Bcl-2 downregulation. Etoposide induced a caspase-dependent cleavage of Bcl-2, while actin remained intact. The Fas system did not seem to play a major role in any of these apoptotic pathways. Our results may provide new tools to study the mechanisms of apoptosis in MDS.

Topics: Actins; Acute Disease; Amino Acid Chloromethyl Ketones; Antibodies, Monoclonal; Apoptosis; Blast Crisis; Caspase Inhibitors; Caspases; Cell Differentiation; Cysteine Proteinase Inhibitors; Cytoskeleton; Erythropoietin; Etoposide; fas Receptor; Granulocyte Colony-Stimulating Factor; Humans; Leukemia, Myeloid; Myelodysplastic Syndromes; Neoplasm Proteins; Proto-Oncogene Proteins c-bcl-2; Signal Transduction; Tretinoin; Tumor Cells, Cultured

Different types of acute myeloid leukemia blast cells were induced to differentiate in vitro with all-trans-retinoic acid (ATRA) and vitamin D3 (VD). M0/M1 leukemic cells are not sensitive to differentiating agents, whereas M3 leukemic cells are induced to undergo granulocytic differentiation after ATRA treatment but are not sensitive to VD. M2 leukemic blast cells behave differently because they undergo monocytic differentiation with both the differentiation inducers. To gain some insight into the maturation of M2-type leukemic cells, we studied the molecular mechanisms underlying monocytic differentiation induced by ATRA and VD in spontaneous M2 blast cells as well as in Kasumi-1 cells (an acute myeloid leukemia M2-type cell line). Our results indicate that ATRA as well as VD efficiently increases the nuclear abundance of VD receptor (VDR) and promotes monocytic differentiation. VDR is functionally active in ATRA-treated Kasumi-1 cells because it efficiently heterodimerizes with retinoid X receptor, binds to a DR3-type vitamin D-responsive element, and activates the transcription of a vitamin D-responsive element-regulated reporter gene. Consistent with these findings, VD-responsive genes are induced by ATRA treatment of Kasumi-1 cells, suggesting that the genetic program underlying monocytic differentiation is activated. The molecular mechanism by which ATRA increases the nuclear abundance of a functional VDR is still unknown, but our data clearly indicate that the M2 leukemic cell context is only permissive of monocytic differentiation.

Topics: Acute Disease; Calcitriol; Cell Differentiation; Cell Lineage; Cell Nucleus; Dimerization; DNA; Gene Expression Regulation, Leukemic; HL-60 Cells; Humans; Leukemia, Myeloid; Leukemia, Myeloid, Acute; Monocytes; Neoplasm Proteins; Neoplastic Stem Cells; Promoter Regions, Genetic; Protein Multimerization; Receptors, Calcitriol; Receptors, Retinoic Acid; Recombinant Fusion Proteins; Regulatory Sequences, Nucleic Acid; Retinoic Acid Receptor alpha; Retinoid X Receptors; Transcription Factors; Transcription, Genetic; Tretinoin; Tumor Cells, Cultured

The expression of Bcl-2 family members was examined in normal and leukemic hematopoietic cells. Immature hematopoietic progenitor cells (CD34+/33-/13-) did not express Bcl-2 but Bcl-XL, the majority of CD34 cells expressed Bcl-2, Bcl-XL and BAD, and normal promyelocytes (CD34-/33+) lacked expression of both Bcl-2 and Bcl-XL, while leukemic CD34+progenitors and promyelocytes expressed these anti-apoptotic proteins. In AML, Bcl-2 expression was higher on CD34+ than on all AML cells, however, expression of Bcl-2 or Bcl-XL did not predict achievement of complete remission. Surprisingly, low Bcl-2 content was associated with poor survival in a group of patients with poor prognosis cytogenetics. The anti-apoptotic BAD protein was found to be expressed in AML, but was phosphorylated in 41/42 samples. Phosphorylation was found at both sites, Ser 112 and Ser 136. During induction chemotherapy, Bcl-2 levels of CD34 cells increased significantly. In the context of evidence for small numbers of leukemic CD34+ cells expressing very high levels of Bcl-2 prior to therapy, this finding is interpreted as a survival advantage of Bcl-2 overexpressing progenitors and rapid elimination of cells with low Bcl-2. Bcl-2 and Bcl-XL were both expressed in minimal residual disease cells. Downregulation of Bcl-2 mRNA and protein was observed by ATRA and the combination of Ara-C, followed by ATRA, resulted in markedly increased cytotoxicity in HL-60 cells, as compared to Ara-C alone or ATRA followed by Ara-C. Implications of these findings for the development of new therapeutic strategies for AML are discussed.

Topics: Acute Disease; Antigens, CD34; Antineoplastic Agents; Apoptosis; bcl-2-Associated X Protein; bcl-Associated Death Protein; bcl-X Protein; Carrier Proteins; Cytarabine; Down-Regulation; Flow Cytometry; Gene Expression; Genes, bcl-2; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid; Neoplasm, Residual; Phosphorylation; Phosphoserine; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-bcl-2; RNA, Messenger; Survival Rate; Tretinoin; Tumor Cells, Cultured

To explore the relationship among intercellular -SH, caspase, retinoic acid (RA) and arsenic trioxide(As2O3)-induced apoptosis.. The in vitro effect of different thiols compounds, RA and caspase inhibitors on As2O3-induced apoptosis in NB4 and HL-60 cells was studied.. 1. NAC completely blocked, BSO potentiated while MTG, BAL had no effect on As2O3-induced apoptosis. 2. Z-VAD.fmk blocked while Y-VAD.fmk had no effect on As2O3-induced apoptosis. 3. RA and As2O3 showed synergism in HL-60 cells, while showed antagonism in NB4 cell.. 1. As2O3 binds with intracellular -SH, changes signal transduction, selectively activates caspase and causes apoptosis. 2. The regulating effect of RA on As2O3-induced apoptosis depends on cell types.

Topics: Acute Disease; Antineoplastic Agents; Apoptosis; Arsenic Trioxide; Arsenicals; Caspase Inhibitors; HL-60 Cells; Humans; Leukemia, Myeloid; Oligopeptides; Oxides; Tretinoin; Tumor Cells, Cultured

Autologous peripheral blood haemopoietic stem cells (PBSC) were harvested from 30 patients with de novo acute leukaemia, 29 of whom had entered remission following standard chemotherapy. Correlation of CD34+ cells/kg to CFU-GM/kg in the harvests was good (correlation coefficient = 0.72, P < 0.001). We demonstrated significant associations between the CFU-GM content of the harvest and the following: time to platelets >50 x 10(9)/l post final induction course (P < 0.001), days to harvest from day 1 of intensification/mobilization (correlation coefficient = -0.73, P < 0.001), platelets >20 x 10(9)/l at time of harvest (P = 0.02), time to WBC >1.0 x 10(9)/l post intensification/mobilization (correlation coefficient = -0.70, P < 0.001), and WBC on day of harvest (correlation coefficient = 0.60, P < 0.001). In contrast, we found no relationship between the CFU-GM content of the harvest and patient age up to 65 years, presence of absence of coexistent features of trilineage myelodysplasia at diagnosis, number of induction courses to remission or total number of courses of chemotherapy prior to intensification/mobilization. Haemopoietic recovery after reinfusion of PBSC was highly correlated to the number of CFU-GM infused (neutrophils >0.5 x 10(9)/l rs = -0.72, P = 0.001; platelets >20 x 10(9)/l unsupported rs = -0.71, P = 0.001). Our results show that the number of induction courses received, and thus exposure to cytotoxic agents received, made no significant difference to subsequent CFU-GM harvest content. We collected superior harvests from those patients with faster platelet recovery following mobilization therapy. We also found that faster platelet recovery following the final induction therapy was a better predictor of the CFU-GM harvest following mobilization than was the neutrophil recovery following final induction.

Topics: Acute Disease; Adolescent; Adult; Antineoplastic Agents, Alkylating; Busulfan; Cyclophosphamide; Female; Granulocyte-Macrophage Colony-Stimulating Factor; Hematopoietic Stem Cell Mobilization; Hematopoietic Stem Cell Transplantation; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid; Leukocyte Count; Male; Middle Aged; Neutrophils; Platelet Count; Tretinoin

Bufalin, a cardiotonic steroid isolated from the Chinese toad venom preparation Chan'su, has differentiation-inducing activity in several myeloid leukemia cell lines. We examined the effect of bufalin on differentiation of leukemic cells from acute myeloid leukemia (AML) patients in primary culture. Bufalin significantly stimulated functional and morphologic differentiation of leukemia cells in four of 20 cases, suggesting that bufalin alone is only a modest inducer of differentiation of AML cells in primary culture. In contrast, acute promyelocytic leukemia (APL) cells showed synergistic differentiation after treatment with all-trans retinoic acid (RA) and bufalin. In some cases, bufalin restored RA sensitivity to previously resistant APL cells. The effective concentration of bufalin for differentiation-inducing activity in APL cells was lower than for its cardiac action. Combined treatment with bufalin and RA may be more effective than RA alone in differentiation therapy of APL.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Bufanolides; Cardiotonic Agents; Cell Differentiation; Drug Resistance, Neoplasm; Drug Synergism; Female; Humans; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Male; Middle Aged; Tretinoin; Tumor Cells, Cultured

In a liquid culture system, all-trans retinoic acid (ATRA), alone and in combination with dihydroxylated vitamin D3 (D3) or alpha interferon (alphaIFN) at concentrations achievable in vivo, could significantly suppress the maintenance of non-promyelocytic myeloid leukemia clonogenic cells (CFU-L) in 9/20, 9/18 and 7/11 cases, respectively. That suppression was counteracted only slightly by the addition of 'stem cell factor', a cytokine which promotes CFU-L expansion in vitro. Differentiated cells slightly increased in 5/17 cases only, suggesting the prevalence of anti-proliferative rather than differentiating mechanisms. The present results extend our previous ones and suggest the possible therapeutical value of ATRA+D3 or alphaIFN, even in cases of non-promyelocytic myeloid leukemia.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Cell Differentiation; Cholecalciferol; Humans; Interferon alpha-2; Interferon-alpha; Leukemia, Myeloid; Middle Aged; Recombinant Proteins; Stem Cell Factor; Tretinoin; Tumor Cells, Cultured

Topics: Acute Disease; Humans; Leukemia, Promyelocytic, Acute; Lipid Metabolism; Male; Middle Aged; Pancreatitis; Tretinoin

Human C/EBP epsilon is a newly cloned CCAAT/enhancer-binding transcription factor. Initial studies indicated it may be an important regulator of human myelopoiesis. To elucidate the range of expression of C/EBP epsilon, we used reverse transcription-polymerase chain reaction (RT-PCR) analysis and examined its expression in 28 hematopoietic and 14 nonhematopoietic cell lines, 16 fresh myeloid leukemia samples, and normal human hematopoietic stem cells and their mature progeny. Prominent expression of C/EBP epsilon mRNA occurred in the late myeloblastic and promyelocytic cell lines (NB4, HL60, GFD8), the myelomonoblastic cell lines (U937 and THP-1), the early myeloblast cell lines (ML1, KCL22, MDS92), and the T-cell lymphoblastic leukemia cell lines CEM and HSB-2. For the acute promyelocytic leukemia cell line NB4, C/EBP epsilon was the only C/EBP family member that was easily detected by RT-PCR. No C/EBP epsilon mRNA was found in erythroid, megakaryocyte, basophil, B lymphoid, or nonhematopoietic cell lines. Most acute myeloid leukemia samples (11 of 12) from patients expressed C/EBP epsilon. Northern blot and RT-PCR analyses showed that C/EBP epsilon mRNA decreased when the HL60 and KG-1 myeloblast cell lines were induced to differentiate toward macrophages. Similarly, Western blot analysis showed that expression of C/EBP epsilon protein was either unchanged or decreased slightly as the promyelocytic cell line NB4 differentiated down the macrophage-like pathway after treatment with a potent vitamin D3 analog (KH1060). In contrast, C/EBP epsilon protein levels increased dramatically as NB4 cells were induced to differentiate down the granulocytic pathway after exposure to 9-cis retinoic acid. Furthermore, very early, normal hematopoietic stem cells (CD34+/CD38-), purified from humans had very weak expression of C/EBP epsilon mRNA, but levels increased as these cells differentiated towards granulocytes. Likewise, purified granulocytes appeared to express higher levels of C/EBP epsilon mRNA than purified macrophages. Addition of phosphothiolated antisense, but not sense oligonucleotides to C/EBP epsilon, decreased clonal growth of HL-60 and NB4 cells by about 50% compared with control cultures. Taken together, our results indicate that expression of C/EBP epsilon is restricted to hematopoietic tissues, especially myeloid cells as they differentiate towards granulocytes and inhibition of its expression in HL-60 and NB4 myeloblasts and promyelocytes decreased

Topics: Acute Disease; Alitretinoin; Blotting, Western; Calcitriol; CCAAT-Enhancer-Binding Proteins; Cell Differentiation; Cell Line; DNA-Binding Proteins; Gene Expression Regulation; Gene Expression Regulation, Leukemic; Granulocytes; Hematopoiesis; Hematopoietic Stem Cells; HL-60 Cells; Humans; Leukemia, Myeloid; Monocytes; Neoplasm Proteins; Nuclear Proteins; Oligonucleotides, Antisense; Polymerase Chain Reaction; RNA, Messenger; RNA, Neoplasm; Tretinoin

The relationship between differentiation of human myeloid cells and apoptosis remains unclear. Recent studies have shown that terminal differentiation need not necessarily lead to the apoptotic demise of myeloid cells, while other studies have shown that induction of differentiation is associated with increased resistance to apoptosis-inducing agents, such as chemotherapy and gamma-irradiation. Such results are pertinent to the treatment of acute myeloid leukemia (AML) and myelodysplastic syndrome, where differentiating agents and hemopoietic growth factors are being combined with chemotherapy to enhance response and limit toxicity. To elucidate the factors governing apoptosis in human AML blasts, we have studied the cytotoxic effect of idarubicin on HL60, U937 and KG1 cells, after incubation with all-trans retinoic acid (ATRA), 1, 25(OH)2 D3, and granulocyte-macrophage colony-stimulating factor (GM-CSF ). We show that prior incubation of human myeloid leukemic cells with ATRA or 1,25(OH)2 D3 induced resistance to idarubicin-induced apoptosis, which was modulated by coincubation with GM-CSF. The altered chemosensitivity of cells depended on the degree of G0/G1 cell-cycle arrest induced by incubation with ATRA, 1, 25(OH)2 D3, and GM-CSF and was independent of differentiation status or Bcl-2 oncoprotein expression. These findings suggest that cell-cycle arrest in human leukemic cells can be induced by exogenous agents and may promote drug resistance. Determining the mechanisms by which cell-cycle arrest is induced may permit understanding of the processes by which the cells escape cytotoxic drug-mediated apoptosis.

Topics: Acute Disease; Antibiotics, Antineoplastic; Apoptosis; Calcitriol; Cell Cycle; Cell Differentiation; Drug Resistance, Neoplasm; Granulocyte-Macrophage Colony-Stimulating Factor; HL-60 Cells; Humans; Idarubicin; Leukemia, Myeloid; Proto-Oncogene Proteins c-bcl-2; Tretinoin; Tumor Cells, Cultured

Investigating 208 patients with acute haematological malignancies, we found that stem cell factor receptor (SCFR) was expressed on high numbers of blast cells from the vast majority of patients (93%) with refractory anaemia with excess of blasts in transformation. SCFR was also detected in 62% of AMLs, in which it was directly associated to the expression of CD7, interleukin 6 receptor and CD34, and inversely to that of CD11b and CD14. SCFR-positive cases were preferentially represented in AML-M1 (70%) and in AML-M2 (83%) subsets, whereas only 45% of the remaining samples (M3-M4-M5) exhibited SCFR positively. Interestingly, 50% of cases with acute promyelocytic leukaemia expressed SCFR and this molecule was heterogenously regulated by in vitro treatment with all-trans retinoic acid.

Topics: Acute Disease; Humans; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Lymphocyte Subsets; Proto-Oncogene Proteins c-kit; Tretinoin

Retinoids are important regulators of cell growth and differentiation in vitro and in vivo and they exert their biologic activities by binding to nuclear retinoic acid receptors (RARs; alpha, beta, and gamma) and retinoid X receptors (RXRs; alpha, beta, and gamma). All-trans retinoic acid (RA) induces complete remission in patients with acute promyelocytic leukemia (APL) presumably by binding directly to RAR alpha of APL cells. Leukemic blasts from APL patients initially responsive to RA can become resistant to the agent. HL-60 myeloblasts cultured with RA have developed mutations of the ligand-binding region of RAR alpha and have become resistant to RA. Furthermore, insertion of an RAR alpha with an alteration in the ligand-binding region into normal murine bone marrow cells can result in growth factor-dependent immortalization of the early hematopoietic cells. To determine if alterations of the ligand binding domain of RAR alpha might be involved in several malignant hematologic disorders, the mutational status of this region (exons 7, 8, and 9) was examined in 118 samples that included a variety of cell lines and fresh cells from patients with myelodysplastic syndromes (MDS) and acute myeloid leukemias (AML), including 20 APL patients, 5 of whom were resistant to RA and 1 who was refractory to RA at diagnosis, using polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP) analysis and DNA sequencing. In addition, 7 of the 20 APLs were studied for alterations of the other coding exons of the gene (exons 2 through 6). No mutations of RAR alpha were detected. Although the sensitivity of PCR-SSCP analysis is less than 100%, these findings suggest that alterations of RAR alpha gene are rare and therefore other mechanisms must be involved in the onset of resistance to retinoids and in the lack of differentiation in disorders of the myeloid lineage.

Topics: Acute Disease; Antineoplastic Agents; Base Sequence; Binding Sites; DNA Mutational Analysis; DNA, Neoplasm; Drug Resistance, Neoplasm; Exons; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Molecular Sequence Data; Myelodysplastic Syndromes; Neoplasm Proteins; Neoplastic Stem Cells; Polymerase Chain Reaction; Polymorphism, Single-Stranded Conformational; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Tretinoin; Tumor Cells, Cultured

All-trans retinoic acid (ATRA) increases the sensitivity of AML blast cells to cytosine arabinoside (Ara-C) or daunorubicin (DNR) when ATRA is given after drug. We have proposed that down-regulation of bcl-2 is part of the mechanism by which ATRA regulates drug sensitivity. To test this hypothesis cDNA encoding bcl-2 was transfected into cells of the continuous lines OCI/AML-2 and OCI/AML-5. Four transfectant lines were isolated; three contained transfected bcl-2 in the sense orientation (AML5-BCL2sa, AML5-BCL2sb and 2-bcl2) and one with anti-sense bcl-2(AML5-bcl2as). The presence of the transfected gene was demonstrated by Northern blot; translation of the sense transfected genes into protein was demonstrated by Western blotting. Lines with sense-oriented transfected bcl-2 were significantly less sensitive to Ara-C or H2O2 than the parental lines; the cells with anti-sense transfected genes were more sensitive than their parent but the difference did not reach statistical significance. The effect of ATRA on bcl-2 expression was compared in sense-transfected cells and their parents; by Northern blotting it was shown that the endogenous but not the transfected genes were down-regulated after ATRA exposure. The capacity of cells with transfected genes to respond to ATRA was tested by obtaining Ara-C survival curves for ATRA-treated cells. Compared to controls not exposed to ATRA, the transfected cells showed little or statistically insignificant changes in Ara-C sensitivity after ATRA treatment. We conclude that data from the transfectants provides evidence that expression of bcl-2 is a determinant of sensitivity to Ara-C and H2O2; and that the effect of ATRA on sensitivity requires the presence of bcl-2 genes in association with regulatory elements.

Topics: Acute Disease; Antineoplastic Agents; Cell Survival; Cytarabine; Drug Resistance, Neoplasm; Humans; Hydrogen Peroxide; Leukemia, Myeloid; Oncogenes; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-bcl-2; Transfection; Tretinoin; Tumor Cells, Cultured; Tumor Stem Cell Assay

The membrane expression of CD45RA and CD45RO on fresh leukaemic cells taken from 529 cases of acute haemopoietic malignancies, including 117 B-origin acute lymphoblastic leukaemia (B-origin ALL), 37 T-origin acute lymphoblastic leukaemia (T-origin ALL0, 297 de novo acute myeloid leukaemia (AML), 42 refractory anaemia with excess of blasts in transformation (RAEB-T) and 36 myeloid blastic phase of chronic myelogenous leukaemia (CML-BP-my), was analysed. B-origin ALLs were characterized by the lack of the RO isoform along with the consistent presence of RA. Conversely, a differential expression of the two isoforms was detected in different subsets of T-origin ALL, in that T-stem cell leukaemias (T-SCL: CD7+, CD4-, CD8-, CD1-) preferentially expressed CD45RA whereas conventional T-acute lymphoblastic leukaemias (T-ALL: CD7+, CD4+ and/or CD8+ and/or CD1+) were consistently marked by CD45RO. Within myeloid malignancies, most of AMLs displayed CD45RA, while a substantial group of CML-BP-my preferentially exhibited CD45RO. As a general rule, a reciprocal exclusion of the two isoforms was observed in AML as well as in ALL. Nevertheless, a frequent coexpression of CD45RA and CD45RO was observed in CD14+ AML. In vitro treatment with all-trans retinoic acid (ATRA) was able to promote a switch from CD45RA to CD45RO expression in 27 de novo AML, independently from morphological subtyping. To our knowledge, this is the first report on CD45 isoform expression in a large series of patients with acute leukaemia. The knowledge of the differential expression of CD45RA and CD45RO can ameliorate our classificative approach to haematological malignancies, as well as disclose new multiple overlap points between normal and leukaemic cell differentiation.

Topics: Acute Disease; Anemia, Refractory, with Excess of Blasts; Cell Differentiation; Hematopoiesis; Humans; Immunophenotyping; Isomerism; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Leukemia, Myeloid; Leukocyte Common Antigens; Leukocytes; Myelodysplastic Syndromes; Tretinoin

We studied 18 patients with acute promyelocytic leukaemia and 13 with relapsed APL. We found a significantly elevated EGF in acute leukaemia, especially in APL, being 418.59 +/- 19.2 micrograms in the 24-h urine that was much higher than that of the normal controls. When eight APL patients achieved complete remission by RA treatment, the EGF value decreased to 149.9 +/- 27.3 micrograms in the 24-h urine near to normal. In 13 patients with relapsed APL, EGF rose to 446.9 +/- 82.6 micrograms in the 24-h urine. Most interestingly, this elevated EGF could be detected before the relapse by 5 +/- 0.84 months in seven out of eight APL with relapse. We suggest that the unaccountably elevated EGF during remission period may be an indicator of the occurrence of relapse.

Topics: Acute Disease; Adult; Aged; Base Sequence; Biomarkers, Tumor; Cell Differentiation; Epidermal Growth Factor; Female; Humans; Immunologic Factors; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Male; Middle Aged; Molecular Sequence Data; Neoplasm Proteins; Neoplasm Recurrence, Local; Neoplasm, Residual; Oncogene Proteins, Fusion; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Remission Induction; Tretinoin

ATRA is extremely effective for inducing clinical remission in APML. The presence of PML/RAR-alpha fusion gene produced as a result of the unique chromosomal translocation in APML is a marker of the sensitivity to ATRA therapy. Further research is needed to elucidate the mechanisms by which the development of the fusion protein in APML leads to the arrest of myeloid differentiation. ATRA leads to rapid resolution of the coagulopathy associated with APML. There is a major clinical benefit since coagulopathy often causes early fatal hemorrhage. The effectiveness of ATRA in APML can serve as a paradigm for the use of differentiation therapy in human malignancies.

Topics: Acute Disease; Blood Coagulation; Humans; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Myelodysplastic Syndromes; Tretinoin

We have identified and characterized a previously unrecognized form of acute leukemia that shares features of both myeloid and natural killer (NK) cells. From a consecutive series of 350 cases of adult de novo acute myeloid leukemia (AML), we identified 20 cases (6%) with a unique immunophenotype: CD33+, CD56+, CD11a+, CD13lo, CD15lo, CD34+/-, HLA-DR-, CD16-. Multicolor flow cytometric assays confirmed the coexpression of myeloid (CD33, CD13, CD15) and NK cell-associated (CD56) antigens in each case, whereas reverse transcription polymerase chain reaction (RT-PCR) assays confirmed the identity of CD56 (neural cell adhesion molecule) in leukemic blasts. Although two cases expressed CD4, no case expressed CD2, CD3, or CD8 and no case showed clonal rearrangement of genes encoding the T-cell receptor (TCR beta, gamma, delta). Leukemic blasts in the majority of cases shared unique morphologic features (deeply invaginated nuclear membranes, scant cytoplasm with fine azurophilic granularity, and finely granular Sudan black B and myeloperoxidase cytochemical reactivity) that were remarkably similar to those of acute promyelocytic leukemia (APL); particularly the microgranular variant (FAB AML-M3v). However, all 20 cases lacked the t(15;17) and 17 cases tested lacked the promyelocytic/retinoic acid receptor alpha (RAR alpha) fusion transcript in RT-PCR assays; 12 cases had 46,XX or 46,XY karyotypes, whereas 2 cases had abnormalities of chromosome 17q: 1 with del(17)(q25) and the other with t(11;17)(q23;q21) and the promyelocytic leukemia zinc finger/RAR alpha fusion transcript. All cases tested (6/20), including the case with t(11;17), failed to differentiate in vitro in response to all-trans retinoic acid (ATRA), suggesting that these cases may account for some APLs that have not shown a clinical response to ATRA. Four of 6 cases tested showed functional NK cell-mediated cytotoxicity, suggesting a relationship between these unique CD33+, CD56+, CD16- acute leukemias and normal CD56+, CD16- NK precursor cells. Using a combination of panning and multiparameter flow cytometric sorting, we identified a normal CD56+, CD33+, CD16- counterpart cell at a frequency of 1% to 2% in the peripheral blood of healthy individuals. Our studies suggest that this form of acute leukemia may arise from transformation of a precursor cell common to both the myeloid and NK cell lineages; thus we propose the designation myeloid/NK acute leukemia. Recognition of this new leukemic entity w

Topics: Acute Disease; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Antigens, Differentiation, T-Lymphocyte; Base Sequence; CD56 Antigen; Cell Differentiation; Cytotoxicity, Immunologic; Diagnostic Errors; HLA-DR Antigens; Humans; Immunophenotyping; Killer Cells, Natural; Leukemia; Leukemia, Promyelocytic, Acute; Molecular Sequence Data; Receptors, IgG; Receptors, Retinoic Acid; Sialic Acid Binding Ig-like Lectin 3; Tretinoin

In the present study we investigated the membrane expression of selectin ligands (CD15/Le(x), CDw65/VIM2, CD15s/sLe(x), beta 2 integrins (CD11a/LFA-1, CD11b/Mac-1) and CD45 phosphatase isoforms (CD45RA, CD45O) on leukaemic cells from 28 patients with acute myeloid malignancies cultured with and without all-trans retinoic acid (ATRA). Within each adhesion system. ATRA was able to differentially regulate distinct molecules. Furthermore, it was able to exert effects specific for acute promyelocytic leukaemia (APL) blast cells, as well as to induce a series of non-cytotype-restricted phenotypic changes. An impressive feature of ATRA induction was a simultaneous increase in the expression of CD15, CDw65 and CD11b on leukaemic promyelocytes. The sialylated antigen CD15s, however, showed results independent from the other two carbohydrates (CD15 and CDw65), suggesting a differential enzymatic regulation within the selectin ligands system. In spite of the well-recognized expression of CD11a throughout all stages of normal myeloid differentiation, APL blast cells were found to virtually lack LFA-1 expression. Moreover, ATRA was unable to promote an up-regulation of this antigen in APL, while inducing a frequent down-modulation in non-APL cases constitutively expressing this antigen. In APL cases ATRA generated an asynchronous phenotype (CD15+, CDw65+, CD11b+, CD11a-), undetectable on normally maturing myeloid cells, but consistent with the concept that incomplete differentiation, in terms of surface molecule expression, can be sufficient to obtain therapeutic results.

Topics: Acute Disease; Antigens, CD; CD11 Antigens; Cell Adhesion Molecules; Cell Differentiation; Humans; Leukemia, Myeloid; Lewis X Antigen; Neoplasm Proteins; Tretinoin

Topics: Acute Disease; Adult; Fever; Humans; Leukemia, Promyelocytic, Acute; Male; Pleural Effusion; Respiratory Insufficiency; Syndrome; Tretinoin

Topics: Acute Disease; Adult; Female; Humans; Hypertriglyceridemia; Leukemia, Promyelocytic, Acute; Pancreatitis; Tretinoin

Regulatory molecules that affect the growth culture of blast cells from acute myeloblastic leukemia (AML) may also alter drug sensitivity, a phenomenon that may be called regulated drug sensitivity. Previous studies have shown: (i) blast cells exposed to retinoic acid before cytosine arabinoside (Ara-C) usually show increased sensitivity, but after some retinoic acid exposure times, sensitivity may be decreased; (ii) factor-sensitive or responsive blasts cultured with granulocyte colony-stimulating factor (G-CSF) are regularly more Ara-C-sensitive than when cultured with granulocyte-macrophage CSF (GM-CSF). This paper is concerned with the effects of schedule on drug sensitivity as regulated by either retinoic acid or the myelopoietic growth factors, G-CSF and GM-CSF. We measured the effects of retinoic acid on the sensitivity of blasts cells from the two continuous AML lines to Ara-C or arabinofuranosyl 5-azacytosine (Ara-AC). Cells from seven patients with AML were tested for Ara-C sensitivity in conjunction with retinoic acid. The cells were treated with retinoic acid before or after administration of the drug. Both increases and decreases in Ara-C sensitivity were seen for both schedules. Consistent increases in Ara-C sensitivity were obtained when retinoic acid was included in the methylcellulose cultures used to determine clonogenic cell recovery at each drug dose. In studies of growth factors, a single factor-dependent cell line (OCI/AML-5) was used to compare the effects of G-CSF and GM-CSF on Ara-C sensitivity. An experimental design was used that permitted factors to present in culture for 24 h before Ara-C, during the next 24 h period with the drug, for a subsequent day in suspension without drug, and during the 5-7 days required for colony formation in methylcellulose cultures. G-CSF and GM-CSF were most effective in increasing or decreasing Ara-C, respectively, when the factor under test was included in the methylcellulose cultures. Thus, like retinoic acid, growth factors influenced drug sensitivity when they were present after the drug had been removed. These data, therefore, are compatible with the hypothesis that repair mechanism may contribute to regulated drug sensitivity.

Topics: Acute Disease; Aged; Cell Survival; Cytarabine; Female; Granulocyte Colony-Stimulating Factor; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; In Vitro Techniques; Leukemia, Myeloid; Male; Methylcellulose; Middle Aged; Tretinoin; Tumor Cells, Cultured

Acute myeloid leukemia blasts express dual affinity (high and low) granulocyte-macrophage colony-stimulating factor (GM-CSF) binding, and the high affinity GM-CSF binding is counteracted by excess interleukin-3 (IL-3). Neutrophils express a single class of GM-CSF-R with intermediate affinity that lack IL-3 cross-reactivity. Here we demonstrate the differentiation associated changes of GM-CSF binding characteristics in three models representative of different stages of myeloid maturation. We find that high affinity GM-CSF binding is converted into intermediate affinity binding, which still cross-reacts with IL-3, beyond the stage of promyelocytes. During terminal maturation towards neutrophils, IL-3 cross-reactivity is gradually lost. We sought to determine the mechanism underlying the affinity conversion of the GM-CSF-R. Northern and reverse transcriptase-polymerase chain reaction analysis of GM-CSF-R alpha and -beta c (KH97) transcripts did not provide indications for the involvement of GM-CSF-R splice variants in the formation of the intermediate affinity GM-CSFR complex. In COS-cell transfectants with increasing amounts of beta c in the presence of a fixed number of GM-CSF-R alpha chains, the high affinity GM-CSF binding converted into intermediate affinity GM-CSF binding. These results are discussed in view of the concept that increasing expression of beta c subunits may cause alternative oligomerization of the GM-CSF-R alpha and -beta c subunits resulting in the formation of intermediate rather than high affinity GM-CSFR alpha.beta c complexes.

Topics: Acute Disease; Animals; Base Sequence; Cell Line; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Kinetics; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Macromolecular Substances; Molecular Sequence Data; Oligodeoxyribonucleotides; Polymerase Chain Reaction; Receptors, Granulocyte-Macrophage Colony-Stimulating Factor; Recombinant Proteins; RNA, Neoplasm; Sequence Deletion; Transcription, Genetic; Transfection; Tretinoin; Tumor Cells, Cultured; Up-Regulation

We analyzed the maintenance of acute myeloid leukemia clonogenic cells (AML CFU-L) in liquid culture in the presence of five potential differentiation inducers: trans-retinoic acid, 1,25-dihydroxy vitamin D3, interferon gamma, granulocyte colony-stimulating factor (G-CSF), macrophage colony-stimulating factor (M-CSF), used singly and with two combined. The culture medium contained either fetal bovine or human serum from normal donors. CFU-L recovery after 7 days was compared to that observed in control cultures. Of AML cases and HL60 cells, 11/15 displayed greater than 50% CFU-L reduction in response to one or more inducers. In 8/9 responsive cases that underwent the nitroblue tetrazolium (NBT) reduction test, an increase in the percentage of functionally mature (NBT-positive) cells was detected. The combination of retinoic acid with interferon gamma was most effective in reducing CFU-L recovering (8 responsive/15 AML cases), G-CSF and M-CSF displayed either inhibitory or stimulatory activity in different AML cases. The type of serum employed generally did not affect the response to inducers of differentiation. No significant inhibition of the recovery of granulocyte-macrophage colony-forming units was determined by the five inducers in experiments with three normal bone marrow samples. Our experiments indicate that biological differentiation inducers can reduce AML CFU-L self-renewal and increase the proportion of differentiated cells at concentrations that do not affect normal myelopoiesis and could be achieved during treatments in vivo.

Topics: Acute Disease; Animals; Calcitriol; Cell Transformation, Neoplastic; Drug Synergism; Granulocyte Colony-Stimulating Factor; Humans; Interferon-gamma; Leukemia, Myeloid; Macrophage Colony-Stimulating Factor; Recombinant Proteins; Tretinoin; Tumor Stem Cell Assay

AML cells were cultured free of serum with G-CSF in combination with all-trans-retinoic acid (RA), prostaglandin E2 or 8-bromocyclic AMP to see whether the maturation blockade of these cells could be overcome. The combination G-CSF + RA was most effective in inducing morphologic maturation, i.e. in 7/10 cases. Morphological alterations in response to G-CSF + RA indicated progression of the cells along the granulocytic pathway towards metamyelocytes and granulocytes. However, morphologically mature AML cells remained negative for myeloperoxidase and Sudan black stainings, indicators of granulocytic maturation. Chloracetate esterase positivity and CD15 membrane antigens became expressed on cultured AML cells, i.e. on unstimulated and G-CSF/RA exposed blasts. Ingestion of latex beads and reduction of nitroblue tetrazolium salt occurred in cultured AML cells regardless of the presence of inducers. In almost all cases clonogenic cells persisted after exposure to G-CSF + RA suggesting that subpopulations of immature cells escaped the action of these inducers. Thus although G-CSF + RA were capable of inducing maturation of AML cells along the granulocytic lineage, maturation was incomplete and the effect was evident in a subfraction of the cells only.

Topics: 8-Bromo Cyclic Adenosine Monophosphate; Acute Disease; Bone Marrow; Cell Differentiation; Cells, Cultured; Dinoprostone; Flow Cytometry; Fluorescent Antibody Technique; Granulocyte Colony-Stimulating Factor; Granulocytes; Humans; Kinetics; Leukemia, Myeloid; Staining and Labeling; Tretinoin

We present a case of hypertrophic lupus erythematosus treated with topical tretinoin. To date, we believe this is the first description of such treatment of this disease.

Topics: Acute Disease; Administration, Cutaneous; Adult; Female; Humans; Hypertrophy; Lupus Erythematosus, Cutaneous; Skin; Sunscreening Agents; Tretinoin

To determine the activity of fenretinide in patients with myelodysplastic syndromes, 15 patients were treated (300 mg/d starting dose, escalated to 400 mg/d) for a 12-week course. No responses were observed in 14 evaluable patients. Exacerbation of thrombocytopenia occurred in one patient with chronic myelomonocytic leukemia, who succumbed to an intracerebral hemorrhage after 3 weeks of treatment. Two patients with long-standing stable sideroblastic anemia experienced interval leukemic progression. In one patient, clinical features of chronic myelomonocytic leukemia appeared, characterized by a striking rise in peripheral monocyte count (0.49 x 10(9)/l to 10.8 x 10(9)/l) and hepatosplenomegaly, which resolved promptly after cessation of treatment. The second patient experienced evolution into acute myelomonocytic leukemia with cytogenetic progression. The drug was well tolerated with no patient having to discontinue treatment because of toxicity. We conclude that fenretinide lacks clinical efficacy in the treatment of myelodysplasia and in some patients may enhance leukemic progression.

Topics: Acute Disease; Aged; Cerebral Hemorrhage; Drug Evaluation; Fenretinide; Humans; Leukemia; Leukocytosis; Male; Middle Aged; Monocytes; Myelodysplastic Syndromes; Thrombocytopenia; Tretinoin

Three cell populations with different DNA indices were demonstrated in a case of biphenotypic terminal transferase (TdT)/myeloid-positive acute leukemia which had developed from a pre-leukemic diploid population also expressing biphenotypic features. At the time of development of acute leukemia, flow-cytometric analysis revealed expression of TdT by the diploid, the tetraploid, and the near-triploid cells, but only the tetraploid cells carried the myeloid-specific M2 antigen. Cytogenetic analysis showed four stemlines, diploid, tetraploid, tetraploid with del(2), and near-triploid with del(2) and variable chromosome losses. In vitro treatment with retinoic acid induced the expression of the M2 antigen by the diploid cells as well. This in vitro result is consistent with a myeloid differentiation commitment of the pluripotent leukemic stem cell.

Topics: Acute Disease; Aged; Antigens, Neoplasm; DNA, Neoplasm; Female; Hematopoietic Stem Cells; Humans; Leukemia; Neoplastic Stem Cells; Phenotype; Ploidies; Tretinoin

The use of isotretinoin in therapeutical dermatology has proved to be of great benefit in a series of cutaneous processes, especially in cystic and conglobate acne, where it produces excellent results with a dose of 1 mg/kg/daily. However, its use is not without complications, the majority of which are well known, and doubtlessly others will be brought to light. As for a case of pseudoacne fulminans, the possible etiopathogenic mechanisms of this type of reaction, are under discussion.

Topics: Acne Vulgaris; Acute Disease; Adolescent; Humans; Isotretinoin; Male; Tretinoin

62 evaluable patients with myelodysplastic syndromes (MDS) or acute leukemia were treated with different combinations of low dose ara-C, alpha-interferon (IFN), 1 alpha-hydroxyvitamin D3 (vit D3) and retinoic acid. The aim was to study the efficacy and toxicity of each combination. The overall rate was 44%. Of these, 50% responded favorably to the combination of IFN, vit D3 and retinoic acid (IDR), which was comparable to the response rate of 43% for low-dose ara-C. The results of the IDR treatment may be explained by additive or synergistic effects between the separate drugs in the combination. Ara-C and IDR treatment was generally well-tolerated but interferon gave more side effects than any other drug used in the study. Evaluation of the full combination of ara-C, IFN, vit D3 and retinoic acid was not possible because of toxicity. Marrow hypoplasia was infrequent (5/27 patients) in cases responding favorably to treatment. Complete remissions were not longer than partial remissions or significant responses.

Topics: Actuarial Analysis; Acute Disease; Adolescent; Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Drug Administration Schedule; Female; Humans; Hydroxycholecalciferols; Interferon Type I; Leukemia; Male; Middle Aged; Myelodysplastic Syndromes; Remission Induction; Tretinoin

Topics: Acne Vulgaris; Acute Disease; Adult; Arthritis; Humans; Isotretinoin; Male; Tretinoin

We have used a panel of 5 monoclonal antibodies against normal myeloid-differentiation antigens to determine retinoic acid-induced changes in cell surface antigens on ANLL bone marrow cells from 24 children at the time of diagnosis. Two of these antibodies (T5A7 and 5F1) detect antigens expressed on normal mature granulocytes and on all monocytes, respectively. The percentage of positive cells for each monoclonal antibody was determined by indirect immunofluorescence. After 5 days incubation with 1 microM RA in liquid culture, cells from 11 of 24 patients showed substantially increased expression of one or both antigens detected by T5A7 and 5F1. Leukemic bone marrow cells from these patients were also cultured in methylcellulose medium with and without 1 microM RA for one week, and cells from 16 of 24 patients showed clonal growth. Cultures from 10 of these 16 patients showed RA-induced inhibition of colony growth; of these 10 patients, cultures from six patients showed RA-induced increases in antigens associated with maturing myeloid cells. This suggests that the RA-induced inhibition of clonal growth observed with leukemic cells from these patients may be accompanied by the increased expression of maturation-associated myeloid antigens by these cells in the presence of RA.

Topics: Acute Disease; Antibodies, Monoclonal; Antigens, Surface; Bone Marrow; Cell Differentiation; Cell Survival; Child; Granulocytes; Humans; Leukemia; Methylcellulose; Tretinoin

Twenty-eight patients with severe acne and one with hidradenitis suppurativa and acne were treated for 12 to 16 weeks with a new synthetic retinoid, isotretinoin (Roaccutane). The average dose was 0.56 mg/kg/day. Patients were seen weekly for four weeks and then fortnightly for the remaining treatment period, being evaluated both qualitatively and quantitatively. Twenty-five patients had an excellent response. Two to five months after the end of treatment no patient had relapsed. No patient withdrew because of side effects, but all suffered dry lips. This study confirms the potential of isotretinoin in the treatment of severe acne.

Topics: Acne Vulgaris; Acute Disease; Adult; Capsules; Cheilitis; Drug Evaluation; Female; Follow-Up Studies; Humans; Isotretinoin; Male; Time Factors; Tretinoin

A patient developed transient, acute myopia while on isotretinoin (Accutane) therapy for acne. This idiosynactic adverse reaction has not been previously described. There was a clear relationship between restarting the Accutane and recurrence of the transient myopia.

Topics: Acne Vulgaris; Acute Disease; Adult; Female; Humans; Isotretinoin; Myopia; Tretinoin

Treatment with isotretinoin (retinoic acid), which is frequently used in the control of acne, is associated with transient arthralgias in up to 16% of patients. We encountered two cases of acute, aseptic arthritis of the knee in male patients receiving isotretinoin, during the third week and third month of therapy. Synovial fluid obtained from one of the patients was noninflammatory. The drug concentration in the synovial fluid was 131 ng/mL--a level that was compatible with diffusion from the blood (simultaneous serum concentration, 229 ng/mL). Arthritis resolved in both patients without sequelae, despite continuation of drug treatment in one of them. This observation indicates that arthritis with joint effusion may complicate isotretinoin use; it also suggests that alternative measures should be considered before administering the drug to patients with rheumatologic disorders.

Topics: Acne Vulgaris; Acute Disease; Adult; Arthritis; Humans; Isotretinoin; Male; Tretinoin

Topics: Acne Vulgaris; Acute Disease; Administration, Oral; Humans; Isotretinoin; Tretinoin

Topics: Acute Disease; Administration, Oral; Diethylstilbestrol; Female; Fetus; Gonadal Steroid Hormones; Hepatic Encephalopathy; Humans; Ichthyosis; Infant, Newborn; Male; Maternal-Fetal Exchange; Pregnancy; Research; Skin Diseases; Steroids; Tretinoin; Vitamin A