tretinoin and Leukemia--Myelomonocytic--Acute

Topics: Adult; Antineoplastic Combined Chemotherapy Protocols; Arsenic Trioxide; Arsenicals; Cranial Irradiation; Daunorubicin; Ear Neoplasms; Humans; Injections, Spinal; Leukemia, Myelomonocytic, Acute; Male; Oxides; Radiography; Remission Induction; Sarcoma, Myeloid; Tretinoin

Several adenosine analogs induce the functional and morphological differentiation of myelomonocytic leukemia cells. They can be classified into two types; i.e., those that do/do not require phosphorylation to induce the differentiation of leukemia cells. Neplanocin A, a potent S-adenosylhomocysteine hydrolase inhibitor, induces the differentiation of some leukemia cells without phosphorylation. On the other hand, deoxycoformycin (dCF), a potent adenosine deaminase inhibitor, also induces the myelomonocytic differentiation of leukemia cells when it is treated with deoxyadenosine (dAdo). This differentiation is inhibited by 5'-amino-deoxyadenosine, an inhibitor of (deoxy)adenosine kinase, suggesting that kinase-dependent phosphorylation is involved in the differentiation-inducing effect of dCF plus dAdo. Retinoids induce the differentiation of NB4 cells, a cell line derived from human promyelocytic leukemia. When used in combination with all-trans retinoic acid (ATRA), both NPA and dCF plus dAdo greatly enhance the granulocytic differentiation of NB4 cells. This enhancing effect is greatest when the cells are pretreated with NPA and then with ATRA. On the other hand, pre-exposure of NB4 cells to ATRA greatly potentiates the differentiation induced by dCF plus dAdo, while pretreatment with dCF plus dAdo before exposure to ATRA is less effective. The ATRA-induced differentiation of NB4 cells is effectively augmented by clinically applicable concentrations of these analogs. A clinical strategy that combines intermittent treatment with these analogs and a low dose of ATRA may increase the clinical response and decrease the adverse effects of ATRA.

Topics: Adenosine; Antineoplastic Agents; Cell Differentiation; Deoxyadenosines; Humans; Leukemia, Myelomonocytic, Acute; Models, Chemical; Pentostatin; Tretinoin; Tumor Cells, Cultured

Tretinoin tocoferil is an alpha-tocopherol ester of all-trans retinoic acid (ATRA) and safely used to treat skin ulcers. Tretinoin tocoferil stimulates the formation of granulation tissue in the ulcer, and enhances the migration of guinea pig macrophages and stimulates the proliferation of human skin fibroblasts. These effects are different from those of either ATRA or alpha-tocopherol. Tretinoin tocoferil induces the granulocytic differentiation of human promyelocytic leukemia HL-60 cells, and more than additively enhances cellular differentiation induced by sub-optimal concentrations of ATRA. Tretinoin tocoferil and ATRA synergistically inhibit the proliferation of HL-60 cells, suggesting that tretinoin tocoferil acts differently than ATRA on leukemia cells. Tretinoin tocoferil also enhances the differentiation of HL-60 cells induced by dimethyl sulfoxide, phorbol ester and 1alpha,25-dihydroxyvitamin D3(VD3). Tretinoin tocoferil and VD3 synergistically inhibit the proliferation and induce the differentiation of other myelomonocytic leukemia cells. Toxicity tests in animal models have shown that tretinoin tocoferil is at least 150 times less toxic than ATRA and does not induce teratogenesis. Therefore, the combination of tretinoin tocoferil and VD3 may be useful for treating myelomonocytic leukemia.

Topics: Antineoplastic Agents; Cell Differentiation; Drug Combinations; Humans; Leukemia, Myelomonocytic, Acute; Tretinoin; Vitamin E

Heat shock protein (HSP) 70 and HSP90 are released by primary human acute myeloid leukemia (AML) cells during stress-induced spontaneous in vitro apoptosis. The AML cells also show constitutive release of several cytokines and the systemic serum levels of several soluble mediators are altered in patients with untreated AML. In the present study, we have investigated serum levels of HSP70/HSP90 and the serum cytokine profiles of patients with untreated AML and patients receiving AML-stabilizing palliative treatment based on all-trans retinoic acid (ATRA) plus valproic acid. Patients with untreated AML showed increased HSP90 levels and a distinct serum cytokine profile when compared with healthy controls, and low pre-therapy HSP90 levels were associated with a prolonged survival during treatment with ATRA + valproic acid + theophyllin. Hierarchical cluster analysis showed a close association between HSP70, HSP90, IL-1 receptor antagonist (IL-1ra), and hepatocyte growth factor (HGF) levels. Furthermore, disease-stabilizing therapy altered the serum-cytokine profile, but the correlations between HSP70/HSP90/IL-1ra/HGF were maintained only when ATRA + valproic acid were combined with theophyllin but not when combined with cytarabine. We conclude that both HSP levels and serum cytokine profiles are altered and may represent possible therapeutic targets or prognostic markers in human AML.

Topics: Adult; Age Factors; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Cytokines; Female; HSP70 Heat-Shock Proteins; HSP90 Heat-Shock Proteins; Humans; Leukemia, Myeloid, Acute; Leukemia, Myelomonocytic, Acute; Male; Middle Aged; Neoplasm Proteins; Palliative Care; Prognosis; Theophylline; Tretinoin; Tumor Cells, Cultured; Valproic Acid

The ETS transcription factor ERG has been implicated as a major regulator of both normal and aberrant hematopoiesis. In acute myeloid leukemias harboring t(16;21), ERG function is deregulated due to a fusion with FUS/TLS resulting in the expression of a FUS-ERG oncofusion protein. How this oncofusion protein deregulates the normal ERG transcription program is unclear. Here, we show that FUS-ERG acts in the context of a heptad of proteins (ERG, FLI1, GATA2, LYL1, LMO2, RUNX1 and TAL1) central to proper expression of genes involved in maintaining a stem cell hematopoietic phenotype. Moreover, in t(16;21) FUS-ERG co-occupies genomic regions bound by the nuclear receptor heterodimer RXR:RARA inhibiting target gene expression and interfering with hematopoietic differentiation. All-trans retinoic acid treatment of t(16;21) cells as well as FUS-ERG knockdown alleviate the myeloid-differentiation block. Together, the results suggest that FUS-ERG acts as a transcriptional repressor of the retinoic acid signaling pathway.

Topics: Amino Acid Motifs; Cell Line, Tumor; Chromosomes, Human, Pair 16; Chromosomes, Human, Pair 21; Dimerization; Enhancer Elements, Genetic; Gene Expression Regulation, Neoplastic; Hematopoiesis; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid, Acute; Leukemia, Myelomonocytic, Acute; Multiprotein Complexes; Neoplasm Proteins; Neoplastic Stem Cells; Oncogene Proteins, Fusion; Promoter Regions, Genetic; Protein Binding; Protein Interaction Mapping; Proto-Oncogene Proteins; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Retinoid X Receptors; RNA Interference; RNA-Binding Protein FUS; RNA, Small Interfering; Signal Transduction; Trans-Activators; Transcription Factors; Translocation, Genetic; Tretinoin; U937 Cells

CCAAT/enhancer binding protein alpha (C/EBPα) induction induces monocytic differentiation even in acute myeloid leukaemia (AML). In this study, the induction/activation of C/EBPα in myelomonocytic AML was investigated using a combination of all-trans retinoic acid (ATRA) and RAD001 (Everolimus), a mammalian target of rapamycin complex 1 (mTORC1) inhibitor. Combining these agents increased PU.1, C/EBPε and C/EBPα expression, increased the p42/p30 C/EBPα ratio, and decreased C/EBPα phosphorylation at serine 21, and was accompanied by growth inhibition, induction of CD11b expression and apoptosis in AML cell lines. Thus, agents that induce sufficient levels of C/EBPα expression might be useful in treating AML.

Topics: Apoptosis; CCAAT-Enhancer-Binding Proteins; Cell Differentiation; Cell Line, Tumor; Child; Child, Preschool; Everolimus; Female; Gene Expression Regulation, Leukemic; Humans; Immunosuppressive Agents; Leukemia, Myelomonocytic, Acute; Monocytes; Phosphorylation; RNA Processing, Post-Transcriptional; Sirolimus; Tretinoin; U937 Cells

Topics: Animals; Cell Differentiation; Drosophila melanogaster; Drosophila Proteins; Hematopoietic Stem Cells; Humans; Iron; Iron Chelating Agents; Leukemia, Myeloid, Acute; Leukemia, Myelomonocytic, Acute; Models, Biological; Neoplasm Proteins; Neoplastic Stem Cells; Oncogene Proteins, Fusion; Oxidative Stress; Polycomb Repressive Complex 1; Reactive Oxygen Species; Signal Transduction; Tretinoin; Vitamin D

Nicotinamide, the amide derivative of vitamin B(3), cooperates with retinoic acid (RA), a form of vitamin A, and 1,25-dihydroxyvitamin D(3) (D3), to regulate cell differentiation and proliferation of human myeloblastic leukemia cells. In human myeloblastic leukemia cells, RA or D3 are known to cause MAPK signaling leading to myeloid or monocytic differentiation and G0 cell cycle arrest. In this process, RA or D3 induces the early expression of CD38, a receptor that causes ERK signaling and propels further differentiation. Our study demonstrates that nicotinamide in combination with RA or D3 affected induced expression levels of CD38, CD11b and CD14, suggesting a cooperative function of nicotinamide and RA or D3. Nicotinamide transiently retarded the initial RA- or D3-induced expression of CD38, which subsequently reached the same nearly 100% expression. Nicotinamide induced ERK activation and further enhanced the RA-induced ERK activation, but the D3-induced ERK activation was diminished by nicotinamide, although levels still exceeded those induced by RA, suggesting lineage-specific nicotinamide responses. Nicotinamide enhanced both RA- and D3-induced CD11b expression, inducible oxidative metabolism, and G0 cell cycle arrest, accelerating their induced occurrence in all instances. Consistent with this, the RA- or D3-induced downregulation of PARP was enhanced by nicotinamide. Nicotinamide thus regulated RA- or D3-induced differentiation and G0 arrest, causing a transient delay in certain early aspects of the progression to terminal differentiation but ultimately accelerating the occurrence of terminally, functionally differentiated G0 cells.

Topics: ADP-ribosyl Cyclase 1; Calcitriol; CD11b Antigen; Cell Cycle; Cell Differentiation; Drug Synergism; Enzyme Activation; Extracellular Signal-Regulated MAP Kinases; Gene Expression Regulation, Neoplastic; HL-60 Cells; Humans; Leukemia, Myelomonocytic, Acute; Lipopolysaccharide Receptors; Niacinamide; Tretinoin

Leukemias are differentially sensitive to histone deacytelase inhibitor (HDI)-induced apoptosis, but molecular reasons for this remain unclear. We here show that BCR/ABL-, but not FMS-like tyrosine kinase 3 (FLT3)-internal tandem duplication (ITD)-transformed 32D cells or primary acute myeloid leukemia (AML) blasts undergo apoptosis after treatment with the HDI valproic acid (VPA) plus all-trans retinoic acid (VPA/ATRA). A particular VPA/ATRA responsiveness of Philadelphia chromosome-positive (Ph+) acute lymphatic leukemia (ALL) was confirmed in a therapy-refractory patient in vivo. HDI-stimulated apoptosis in Ph+ cells was caspase dependent, but independent from Akt pathway inhibition. Conversely, separate blockage of the Akt/mTor-signaling pathway was a prerequisite for overcoming apoptosis resistance to VPA/ATRA in FLT3-ITD cells, and primary AML blasts (n = 9). In conclusion, constitutive Akt activation causes apoptosis resistance to VPA/ATRA in AML, but not in Ph+ leukemia. This warrants the application of HDI-based therapies in poor-risk Ph+ ALL, and the use of Akt/mTor inhibitors to overcome HDI resistance in AML.

Topics: Antineoplastic Agents; Apoptosis; Caspases; Cell Transformation, Neoplastic; Drug Resistance, Neoplasm; Enzyme Inhibitors; fms-Like Tyrosine Kinase 3; Fusion Proteins, bcr-abl; Histone Deacetylase Inhibitors; Humans; Leukemia, Myelomonocytic, Acute; Mutation; Oncogene Protein v-akt; Philadelphia Chromosome; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Protein Kinases; Signal Transduction; TOR Serine-Threonine Kinases; Tretinoin; Tumor Cells, Cultured; Valproic Acid

p62(DOK1) (DOK1) and p56(DOK2) (DOK2) are sequence homologs that act as docking proteins downstream of receptor or nonreceptor tyrosine kinases. Originally identified in chronic myelogenous leukemia cells as a highly phosphorylated substrate for the chimeric p210(bcr-abl) protein, DOK1 was suspected to play a role in leukemogenesis. However, p62(DOK1-/-) fibroblast knockout cells were found to have enhanced MAPK signaling and proliferation due to growth factors, suggesting negative regulatory capabilities for DOK1. The role of DOK1 and DOK2 in leukemogeneis thus is enigmatic. The data in this report show that both the DOK1 and the DOK2 adaptor proteins are constitutively expressed in the myelomonoblastic leukemia cell line, HL-60, and that expression of both proteins is induced by the chemotherapeutic differentiation causing agents, all-trans retinoic acid (atRA) and 1,25-dihydroxyvitamin D3 (VD3). Ectopic expression of either protein enhances atRA- or VD3-induced growth arrest, differentiation, and G(0)/G(1) cell cycle arrest and results in increased ERK1/2 phosphorylation. DOK1 and DOK2 are similarly effective in these capabilities. The data provide evidence that DOK1 and DOK2 proteins have a similar role in regulating cell proliferation and differentiation and are positive regulators of the MAPK signaling pathway in this context.

Topics: Adaptor Proteins, Signal Transducing; Calcitriol; Cell Cycle; Cell Differentiation; Cell Line, Tumor; Cell Proliferation; DNA-Binding Proteins; Drug Screening Assays, Antitumor; Flow Cytometry; Gene Expression Profiling; Gene Expression Regulation, Leukemic; HL-60 Cells; Humans; Leukemia, Myelomonocytic, Acute; MAP Kinase Signaling System; Mitogen-Activated Protein Kinase Kinases; Molecular Sequence Data; Phenotype; Phosphoproteins; Resting Phase, Cell Cycle; Reverse Transcriptase Polymerase Chain Reaction; RNA-Binding Proteins; Signal Transduction; Structure-Activity Relationship; Time Factors; Tretinoin

A 54-year-old female with acute myeloid leukemia (AML) (FAB M4eo) was treated at second relapse with a combination of low-dose cytosine arabinoside (LDAraC) (20 mg b.i.d. subcutaneously) and all-trans retinoic acid (ATRA) (45 mg/m2/d orally) on days 1-10. The patient achieved a complete hematological remission after the first cycle and was consolidated with three similar cycles at four-week intervals. Subsequently, the patient relapsed several times. Altogether seven complete hematological remissions including some cytogenetic remissions were induced with the same regimen. The patient survived 81 months after the start with LDAraC-ATRA regimen. This low-toxicity regimen may be useful in some patients with poor-risk AML.

Topics: Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Cytogenetic Analysis; Female; Humans; Leukemia, Myelomonocytic, Acute; Middle Aged; Recurrence; Remission Induction; Tretinoin

Histone deacetylase (HDAC)-dependent transcriptional repression of the retinoic acid (RA)-signaling pathway underlies the differentiation block of acute promyelocytic leukemia. RA treatment relieves transcriptional repression and triggers differentiation of acute promyelocytic leukemia blasts, leading to disease remission. We report that transcriptional repression of RA signaling is a common mechanism in acute myeloid leukemias (AMLs). HDAC inhibitors restored RA-dependent transcriptional activation and triggered terminal differentiation of primary blasts from 23 AML patients. Accordingly, we show that AML1/ETO, the commonest AML-associated fusion protein, is an HDAC-dependent repressor of RA signaling. These findings relate alteration of the RA pathway to myeloid leukemogenesis and underscore the potential of transcriptional/differentiation therapy in AML.

Topics: Acetylation; Antineoplastic Agents; Cell Differentiation; Core Binding Factor Alpha 2 Subunit; Enzyme Inhibitors; Gene Expression Regulation, Leukemic; Histone Deacetylase Inhibitors; Histone Deacetylases; Histones; Humans; Hydroxamic Acids; Leukemia, Myeloid, Acute; Leukemia, Myelomonocytic, Acute; Oncogene Proteins, Fusion; RUNX1 Translocation Partner 1 Protein; Signal Transduction; Transcription Factors; Transcriptional Activation; Tretinoin; Tumor Cells, Cultured

We report two cases of acute myeloid leukaemia FAB classification M4Eo with high white cell counts at presentation, who developed acute respiratory failure with pulmonary infiltrates on chest radiograph soon after commencing conventional cytotoxic chemotherapy plus all-trans retinoic acid (ATRA). We suggest that in patients with M4Eo ATRA should be used with caution, perhaps delaying its commencement until the white cell count is < 10 x 109/l.

Topics: Adult; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Daunorubicin; Dexamethasone; Female; Glucocorticoids; Humans; Leukemia, Myelomonocytic, Acute; Remission Induction; Respiratory Insufficiency; Thioguanine; Tretinoin

Previous studies have demonstrated that combinations of all-trans retinoic acid (ATRA) with either granulocyte-colony stimulating factor (G-CSF) or lithium chloride (LiCl) produced synergistic terminal differentiation of WEHI-3B myelomonocytic leukemia (D(+)) cells. It was found that steady-state retinoic acid receptor alpha (RARalpha) protein levels were markedly reduced in these cells after exposure to ATRA. Because the presence of receptors for a hormone ligand is required for its action, differentiation therapy with ATRA may be self-limiting. The combination of G-CSF with ATRA significantly attenuated the loss of RARalpha protein, and synergistic terminal differentiation occurred. LiCl was more effective than G-CSF in preserving RARalpha pools and synergized with ATRA more strongly than G-CSF. These findings suggested that the prevention of RARalpha protein loss by G-CSF or LiCl in ATRA-treated cells functioned to extend the differentiation response to the retinoid and was responsible, at least in part, for the observed synergism. D(+) cells transfected with an expression plasmid containing RARalpha cDNA had a 6- to 8-fold increase in steady-state RARalpha mRNA compared with vector-transfected cells and showed a 2- to 3-fold increase in RARalpha protein. ATRA caused a reduction, but not a complete loss, of RARalpha protein in these transfectants, which were considerably more responsive than parental D(+) cells to ATRA as a single agent, supporting the concept that the protection of RARalpha pools results in a heightened differentiation response to ATRA.

Topics: Antineoplastic Agents; Cell Differentiation; Drug Synergism; Granulocyte Colony-Stimulating Factor; Humans; Leukemia, Myelomonocytic, Acute; Lithium Chloride; Receptors, Retinoic Acid; Tretinoin; Tumor Cells, Cultured

Topics: Cytarabine; Humans; Leukemia, Myelomonocytic, Acute; Leukocyte Count; Leukocytosis; Male; Middle Aged; Syndrome; Tretinoin

Homeobox genes (HOX) may have a regulatory function in the differentiation process of hematopoiesis. We examined the change of HOX B6 and HOX B9 mRNA expressions during the in vitro differentiation of four myeloid leukemia cell lines because HOX B6 may be involved closely in myeloid differentiation. HL-60, NB4, NKM-1 and NOMO-1 were established from acute leukemia of M2, M3, M2 and M5 subtype of the French-American-British classification, respectively. All-trans retinoic acid (ATRA), TPA, and G-CSF were used as differentiation inducers. Each cell line was cultured with each inducer and total RNA was isolated on day 1, 2, 3, or 5. HOX B mRNA was detected by Northern blotting and RT-PCR methods. HOX B6 and HOX B9 mRNAs were constitutively expressed in NB4, NKM-1 and NOMO-1, but were expressed at very low levels in HL-60. HOX B6 and HOX B9 mRNAs were also expressed in fresh acute myelocytic leukemia blasts. HOX B6 mRNA expression in HL-60, NB4, and NKM-1 cultured with ATRA increased on day 3 and decreased on day 5. HOX B6 mRNA expression in NB4 and NKM-1 cultured with TPA decreased on day 3. HOX B9 mRNA expression displayed changes similar to those of HOX B6 mRNA in NB4 and NKM-1. These results indicate that myeloid leukemia cell lines express HOX B6 and HOX B9, and that their respective mRNA expressions in NB4 and HL-60 increase at a mid stage of myeloid differentiation by ATRA induction and then decrease during a late stage. HOX B6 mRNA expression decreased in monocytoid differentiation by TPA induction in NB4, HL-60 and NKM-1. HOX B6 antisense-oligonucleotide inhibited the proliferation of NB4 and NKM-1. These results suggest that HOX B gene expression is related to simultaneous activation of cellular proliferation and differentiation in leukemic cells.

Topics: Cell Differentiation; Cell Division; Gene Expression Regulation, Leukemic; Genes, Homeobox; Granulocyte Colony-Stimulating Factor; HL-60 Cells; Homeodomain Proteins; Humans; Leukemia, Myeloid, Acute; Leukemia, Myelomonocytic, Acute; Neoplasm Proteins; Neoplastic Stem Cells; Oligonucleotides, Antisense; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; RNA, Neoplasm; Tetradecanoylphorbol Acetate; Tretinoin; Tumor Cells, Cultured

To investigate whether apoptosis occurs in vivo in patients with acute leukemia during induction chemotherapy and its significance.. Apoptotic effect on peripheral blood of 20 patients with different types of acute leukemia prior to and during routine chemotherapy was studied by cell morphology, DNA electrophoresis and FCM-DNA analysis.. After chemotherapy, with falls in WBC and blast count, no apoptotic cell appeared on smears of peripheral blood, nor did ladder pattern of DNA on electrophoresis and subdiploid peak on FCM.. Although anticancer drugs have been shown to induce apoptosis in vitro, circulating apoptotic cells are hardly detected probably due to their rapid clearance from the circulation. It is more difficult to study apoptosis in vivo than in vitro.

Topics: Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Daunorubicin; Humans; Leukemia, Myeloid, Acute; Leukemia, Myelomonocytic, Acute; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Prednisone; Tretinoin; Vincristine

Topics: Alitretinoin; Antineoplastic Combined Chemotherapy Protocols; Cell Differentiation; Cell Division; Humans; Leukemia, Myelomonocytic, Acute; Tretinoin; Vitamin D

Myeloperoxidase (MPO) catalyzes a reaction between chloride and hydrogen peroxide to generate hypochlorous acid and other reactive compounds that have been linked to DNA damage. The MPO gene is expressed at high levels in normal myeloid precursors and in acute myeloid leukemias (AMLs) which are clonal derivatives of myeloid precursors that have lost the ability to differentiate into mature blood cells. Two MPO alleles differ at -463 G/A within a cluster of nuclear receptor binding sites in an Alu element. The -463 G creates a stronger SP1 binding site and retinoic acid (RA) response element (RARE) in the allele termed Sp. In this study, we investigate potential links between MPO genotype, MPO expression level, and myeloid leukemia. The SpSp MPO genotype is shown to correlate with increased MPO mRNA levels in primary myeloid leukemia cells. This higher-expressing SpSp genotype is further shown to be overrepresented in acute promyelocytic leukemia-M3 (APL-M3) and AML-M4, suggesting that higher levels of MPO are associated with an increased risk for this subset of leukemias.

Topics: Alleles; Binding Sites; Cell Transformation, Neoplastic; Disease Susceptibility; DNA Damage; Female; Gene Frequency; Genotype; Humans; Leukemia, Myelomonocytic, Acute; Leukemia, Promyelocytic, Acute; Male; Neoplasm Proteins; Peroxidase; Polymerase Chain Reaction; Risk; RNA, Messenger; RNA, Neoplasm; Tretinoin

Tretinoin tocoferil is an alpha-tocopherol ester of all-trans retinoic acid (RA) and safely used in the treatment of skin ulcer. Tretinoin tocoferil inhibited proliferation of human promyelocytic leukemia HL-60 cells and induced granulocytic differentiation of the cells, but less than RA. alpha-Tocopherol did not affect differentiation of HL-60 cells, but at high concentrations enhanced its nitroblue tetrazolium (NBT)-reducing activity and expression of surface antigen CD11b, which are markers of myelomonocytic differentiation induced by RA. Tretinoin tocoferil increased NBT reduction in HL-60 cells treated with RA. It also enhanced the differentiation of HL-60 cells induced by dimethyl sulfoxide, phorbol-12-myristate 13-acetate or 1alpha,25-dihydroxyvitamin D3 (VD3). In combination with a low concentration of VD3, it induced the NBT-reducing activity of human monoblastic U937 cells very effectively. Moreover, it enhanced the differentiation of human myelomonocytic ML-1, THP-1, P39/TSU, and P31/FUJ cells induced by VD3. In combination with VD3, it synergistically inhibited the proliferation of HL-60, U937, ML-1, THP-1, P39/TSU, and P31/FUJ cells and decreased the effective concentration of VD3 to a 10(-10) mol/L level. Because tretinoin tocoferil was reported to induce neither retinoid-related toxicity nor teratogenicity, the therapeutic advantage of the use of it in treatment of myelomonocytic leukemia is suggested.

Topics: Antineoplastic Agents; Calcitriol; Cell Differentiation; Cell Division; Dimethyl Sulfoxide; Drug Combinations; Drug Screening Assays, Antitumor; Drug Synergism; Growth Inhibitors; HL-60 Cells; Humans; Leukemia, Monocytic, Acute; Leukemia, Myelomonocytic, Acute; Lymphoma, Large B-Cell, Diffuse; Neoplastic Stem Cells; Tetradecanoylphorbol Acetate; Tretinoin; Tumor Cells, Cultured; Vitamin E

Bone marrow transplantation procedure has emerged as an effective treatment for hematological malignancies. However, recurrence of leukemia is still the major cause of treatment failure. Subsequent treatment in this category of patients, generally considered incurable, has not been yet standardized. At our institution, 13 patients, 7 with acute non lymphoid leukemia (ANLL) and 6 with acute lymphoid leukemia (ALL), were treated at relapse after bone marrow transplantation either autologous or allogeneic (AuBMT 8, ABMT 4) performed in complete remission (CR). The interval between BMT and relapse was less than 9 months in 6 patients (2 ABMT and 4 AuBMT) and more than 9 months in 7 patients. Early relapsed patients showed no response to treatment and died at a median of 5.5 months (range 1-13) after relapse. Late relapse after BMT was characterized by a high percentage of response (5 CR and 1 PR), particularly after intensive chemotherapy and by a longer survival (median 14 months; range 2-36). Chemotherapy after transplantation should be carefully evaluated in patients relapsed after BMT in order to select a population that can achieve long term disease free survival.

Topics: Adolescent; Adult; Antineoplastic Combined Chemotherapy Protocols; Bone Marrow Transplantation; Cytarabine; Female; Humans; Idarubicin; Italy; Leukemia, Myeloid, Acute; Leukemia, Myelomonocytic, Acute; Male; Middle Aged; Neoplasm, Residual; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Prednisone; Remission Induction; Retrospective Studies; Salvage Therapy; Survival Analysis; Treatment Outcome; Tretinoin; Vincristine

It has been shown previously that multilineage human hematopoiesis is maintained within human fetal bone marrow (BM) fragments implanted into severe combined immunodeficient (SCID) mice. We describe here an application of this animal model, the SCID-hu mouse, to the study of human myeloid leukemias. BM cells from 8 patients with various types of myeloid leukemias were injected directly into human bone grafts in the SCID-hu mouse. Cells from 7 patients grew in the human marrow without spreading to the mouse marrow. Cells from 6 of these patients were successfully transferred in vivo to secondary SCID-hu recipients. The surface phenotype and the cytologic features of the leukemia cells were conserved during passage in vivo. Thus, human myeloid leukemia cells could be reproducibly propagated in the human marrow environment in SCID-hu mice. The differentiation of promyelocytic leukemia cells in the SCID-hu mice was induced by all-trans retinoic acid, suggesting that the biologic features of the leukemia cells were maintained as well. Finally, evidence for a leukemic progenitor cell population in one case of acute myelogenous leukemia was provided with this system. This model may provide a useful tool for studying the biology of human myeloid leukemia as well as for evaluating new therapeutic modalities for myeloid leukemias.

Topics: Animals; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Bone Marrow; Humans; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Leukemia, Myeloid; Leukemia, Myeloid, Acute; Leukemia, Myelomonocytic, Acute; Leukemia, Promyelocytic, Acute; Lewis X Antigen; Mice; Mice, SCID; Neoplasm Transplantation; Sialic Acid Binding Ig-like Lectin 3; Transplantation, Heterologous; Tretinoin

The use of lithium chloride in manic-depressive patients and in patients receiving myelo-suppressive cancer chemotherapeutic agents is accompanied by a sustained leukocytosis due to an increase in granulocyte production. This property suggests that lithium chloride may have effects on hematopoietic differentiation. Treatment of cultured WEHI-3B D+ murine myelomonocytic and HL-60 human promyelocytic leukemia cells with millimolar concentrations of lithium chloride resulted in concentration-dependent increases in the number of differentiated myeloid cells, as determined by the ability of the cells to reduce nitroblue tetrazolium and by the binding of myeloid specific antibodies, and was associated with an inhibition of cellular proliferation. The effects of lithium chloride on growth and differentiation were antagonized by KCl, whereas NaCl had little effect. The induction of leukemic cell maturation by lithium chloride was markedly enhanced by the addition of low levels of retinoic acid. In contrast, other differentiation inducing agents (i.e. dimethyl sulfoxide and selenazofurin) had no effect on the degree of maturation induced by lithium. These findings suggest that the combination of lithium chloride and retinoic acid may have clinical utility in the treatment of leukemia through the induction of terminal differentiation.

Topics: Animals; Cell Differentiation; Chlorides; Growth Substances; Hematopoiesis; Humans; Leukemia, Myelomonocytic, Acute; Leukemia, Promyelocytic, Acute; Lithium; Lithium Chloride; Mice; Tretinoin; Tumor Cells, Cultured

The uptake of colloidal gold particles by human monocytes was studied by electron microscopy, with special emphasis on changes in this uptake during the differentiation and maturation of these cells. The way in which leukemic cells of childhood acute non-lymphocytic leukemia (ANLL) can function in this gold uptake was also examined. In monocytes, microendocytosis was temperature-dependent; colloidal gold uptake increased as temperatures rose from 4 degrees C to 37 degrees C. It appeared that gold particles first adhered to the cell surface membrane, were then incorporated into the cytoplasmic vesicles, and then were transported into the granules. Original HL-60 cells and retinoic acid (RA)-treated HL-60 cells, which were differentiating and maturing along the granulocyte lineage, did not ingest colloidal gold particles, but 1,25(OH)2D3-treated HL-60 cells showed colloidal gold uptake during their differentiation and maturation along the monocyte lineage: 68.6% of the cells contained gold particles. Gold uptake was demonstrated in 27.3% of original U937 cells; the percentage increased to 70.3% when they were induced to mature by RA. In 15 specimens of childhood ANLL, none of the M1, M2 or M3 cells showed colloidal gold uptake, whereas 76-97% of M4 and M5 cells showed this uptake. These findings indicate that colloidal gold uptake is a marker of monocyte differentiation and maturation and can provide additional information for ANLL cytology.

Topics: Adolescent; Biomarkers; Calcitriol; Cell Differentiation; Child; Child, Preschool; Endocytosis; Female; Gold; Humans; Infant; Leukemia, Myeloid, Acute; Leukemia, Myelomonocytic, Acute; Leukemia, Promyelocytic, Acute; Leukocytes, Mononuclear; Lymphoma, Large B-Cell, Diffuse; Male; Microscopy, Electron; Neoplastic Stem Cells; Tretinoin; Tumor Cells, Cultured

We analysed the effects of recombinant human G-CSF (rhG-CSF) and retinoic acid (RA) on proliferation and differentiation of HL-60 cells and human acute myeloid leukemic (AML) cells. A synergistic effect on granulocyte differentiation was observed when HL-60 cells and primary cultured acute promyelocyte leukemic cells were cocultured with 10(-8)mol/L RA plus 1:2000 or 1:1000 rhG-CSF. The rhG-CSF plus RA treated cells demonstrated significant increase in the percentage of mature cells. Morphological changes and nitroblue tetrazolium (NBT) reduction activity evidenced more increase than RA treatment alone (P less than 0.001). The results suggest that RA not only inhibits the proliferative action of G-CSF, but also retains and enhances the action of G-CSF to induce differentiation. Therefore, we believe that the combined use of G-CSF with RA may improve the treatment of leukemia.

Topics: Cell Differentiation; Cell Division; Granulocyte Colony-Stimulating Factor; Granulocytes; Humans; Leukemia, Myeloid, Acute; Leukemia, Myelomonocytic, Acute; Leukemia, Promyelocytic, Acute; Recombinant Proteins; Tretinoin; Tumor Cells, Cultured

Topics: Animals; Biological Factors; Cell Differentiation; Cell Line; Cytokines; Growth Substances; Humans; Interleukin-1; Leukemia, Experimental; Leukemia, Myelomonocytic, Acute; Leukemia, Promyelocytic, Acute; Mice; Recombinant Proteins; Tretinoin

The regulation of IgG Fc receptor (Fc gamma R) expression by retinoic acid (RA) in human myelomonocytic cells at different stages of maturation was studied. RA suppressed IgG-coated erythrocyte (EA) rosette formation of myelomonocytic cells blocked at relatively late stages of differentiation such as ML-1, U-937, THP-1-T, normal monocytes, and fresh cells of patients with acute myelomonocytic leukemia. However, RA increased the percentage of EA rosetting promyelocytes of HL-60 and of patients with acute promyelocytic leukemia and a part of myeloblasts isolated from acute myelogenous leukemia patients. Other myeloblasts including KG-1a, KG-1, and fresh cells from patients with acute myelogenous leukemia were not affected. A kinetic study using HL-60 and THP-1-T demonstrated that an increase required at least a 48-h exposure and that the maximum decrease required approximately 6 h. The RA effect on both cell lines was dose-dependent. The number of Fc gamma R of HL-60 and THP-1-T treated with RA became very close, although untreated THP-1 had almost 10 times as many as HL-60. Kd for IgG in both THP-1-T and HL-60, either untreated or treated with RA, remained unchanged. These observations indicate that one of the important roles of RA is regulation of Fc gamma R expression in myeloid cells.

Topics: Antigens, Differentiation; Binding Sites; Cell Differentiation; Cell Line; Humans; Immunoglobulin G; Kinetics; Leukemia, Myelomonocytic, Acute; Monocytes; Receptors, Fc; Receptors, IgG; Rosette Formation; Tretinoin