cholecalciferol and Leukemia--Promyelocytic--Acute

cholecalciferol has been researched along with Leukemia--Promyelocytic--Acute* in 33 studies

Reviews

1 review(s) available for cholecalciferol and Leukemia--Promyelocytic--Acute

ArticleYear
Cotylenin A--a plant growth regulator as a differentiation-inducing agent against myeloid leukemia.
    Leukemia & lymphoma, 2002, Volume: 43, Issue:6

    Acute myeloid leukemia (AML) is characterized by the arrest of differentiation leading to the accumulation of immature cells. This maturation arrest can be reversed by certain agents. Although differentiation therapy for patients with acute promyelocytic leukemia (APL) using all-trans retinoic acid (ATRA) has been established, the clinical response of AML patients other than those with APL to ATRA is limited. We must consider novel therapeutic drugs against other forms of AML for the development of a differentiation therapy for leukemia. Regulators that play an important role in the differentiation and development of plants or invertebrates may also affect the differentiation of human leukemia cells through a common signal transduction system, and might be clinically useful for treating AML. Cotylenin A, a plant growth regulator, is a potent and novel inducer of the monocytic differentiation of human myeloid leukemia cell lines and leukemia cells freshly isolated from AML patients.

    Topics: Animals; Antigens, Differentiation; Antineoplastic Agents, Phytogenic; Cell Differentiation; Cholecalciferol; Diterpenes; Drug Screening Assays, Antitumor; Drug Synergism; HL-60 Cells; Humans; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Mice; Neoplastic Stem Cells; Retinoids; Structure-Activity Relationship; Tretinoin; Tumor Cells, Cultured

2002

Other Studies

32 other study(ies) available for cholecalciferol and Leukemia--Promyelocytic--Acute

ArticleYear
Potent reducing effects of vitamin D3 on the frequency of apoptosis induced by arsenic trioxide in NB4 cell line.
    Archives of Iranian medicine, 2010, Volume: 13, Issue:1

    Arsenic trioxide and 1,25-(OH)2D3 (vitamin D3) are used for the treatment of lymphocytic leukemia. However, the effects of combined treatment of these drugs are controversial. In this study, the combined effects of these drugs on the induction of apoptosis in NB4 cells were investigated using the neutral comet assay.. NB4 cells were treated with various doses of arsenic trioxide (0.1 - 3 microM) and vitamin D3 (100 - 600 nM (alone or in combination. Twenty-four hours after treatment, neutral comet assay was performed and apoptotic cells were scored under a fluorescent microscope following staining with ethidium bromide.. Results show that all doses of arsenic trioxide used in this study induced apoptosis in NB4 cells. The frequency of induced apoptosis was dose dependent and significantly higher than the controls (P<0.05 - 0.01). In contrast, vitamin D3 at concentrations of 100 - 600 nM produced no significant effect on apoptosis induction compared to the controls. Treatment of NB4 cells with a combination of arsenic trioxide and vitamin D3 resulted in reduction of apoptosis induced by arsenic trioxide which was not dependent on the dose of vitamin D3 (P<0.05).. Results indicate that arsenic trioxide is a potent inducer of apoptosis in NB4 cells and vitamin D3 significantly decreased the sensitivity of cells to the induction of apoptosis by arsenic trioxide. These findings suggest that 1,25-(OH)2D3 might be involved in anti-apoptotic processes via reactive oxygen species scavenging or other mechanisms not yet known.

    Topics: Antineoplastic Agents; Apoptosis; Arsenic Trioxide; Arsenicals; Cell Line, Tumor; Cell Survival; Cholecalciferol; Dose-Response Relationship, Drug; Humans; Leukemia, Promyelocytic, Acute; Oxides

2010
Differentiation response of acute promyelocytic leukemia cells and PML/RARa leukemogenic activity studies by real-time RT-PCR.
    Molecular biotechnology, 2005, Volume: 30, Issue:3

    Acute promyelocytic leukemia (APL) is a human cancer generated by a chromosomal translocation t(15;17) involving the promyelocytic leukemia (PML) and retinoic acid receptor alpha (RARalpha) genes. The PML/RARalpha oncoprotein expressing blasts show two of the most important biological features of neoplastic progression: block of differentiation, at the promyelocytic state, and increased survival. Although PML/RARalpha interferes with the normal maturation of myeloid precursors to granulocytes, pharmacological doses of retinoic acid are sufficient to restore the differentiation processes. We designed an assay based on the Real-Time reverse transcriptase polymerase chain reaction (RT-PCR) to experimentally follow the differentiation response of leukemic cells even after short-time differentiating treatments. Amplifying CD11b, CD11c, and CD14 mRNAs, as specific markers of differentiation, by the real-time RT-PCR assay we could detect both retinoic acid (RA) and vitamin D3 and human transforming growth factor beta1 (VitD3/TGFbeta1) induced cellular maturation more precociously than the canonical flow-cytofluorimetric assay. Moreover, by amplifying CD14 mRNA it was possible to monitor the ability of PML/RARalpha oncoprotein to block VitD3/TGFbeta1 induced differentiation in U937-PR9 promonocytic inducible model systems.The proposed real-time quantitative RT-PCR approach is a reproducible and highly sensitive assay and can be considered a valid method to study both cellular maturation state and differentiation response.

    Topics: Cell Differentiation; Cell Line, Tumor; Cholecalciferol; Humans; Leukemia, Promyelocytic, Acute; Neoplasm Proteins; Nuclear Proteins; Promyelocytic Leukemia Protein; Proteins; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Reverse Transcriptase Polymerase Chain Reaction; Transcription Factors; Tretinoin; Tumor Suppressor Proteins

2005
Role of promyelocytic leukemia (PML) protein in tumor suppression.
    The Journal of experimental medicine, 2001, Feb-19, Volume: 193, Issue:4

    The promyelocytic leukemia (PML) gene encodes a putative tumor suppressor gene involved in the control of apoptosis, which is fused to the retinoic acid receptor alpha (RARalpha) gene in the vast majority of acute promyelocytic leukemia (APL) patients as a consequence of chromosomal translocations. The PMLRARalpha oncoprotein is thought to antagonize the function of PML through its ability to heterodimerize with and delocalize PML from the nuclear body. In APL, this may be facilitated by the reduction to heterozygosity of the normal PML allele. To determine whether PML acts as a tumor suppressor in vivo and what the consequences of deregulated programmed cell death in leukemia and epithelial cancer pathogenesis are, we crossed PML(-/-) mice with human cathepsin G (hCG)-PMLRARalpha or mammary tumor virus (MMTV)/neu transgenic mice (TM), models of leukemia and breast cancer, respectively. The progressive reduction of the dose of PML resulted in a dramatic increase in the incidence of leukemia, and in an acceleration of leukemia onset in PMLRARalpha TM. By contrast, PML inactivation did not affect neu-induced tumorigenesis. In hemopoietic cells from PMLRARalpha TM, PML inactivation resulted in impaired response to differentiating agents such as RA and vitamin D3 as well as in a marked survival advantage upon proapoptotic stimuli. These results demonstrate that: (a) PML acts in vivo as a tumor suppressor by rendering the cells resistant to proapoptotic and differentiating stimuli; (b) PML haploinsufficiency and the functional impairment of PML by PMLRARalpha are critical events in APL pathogenesis; and (c) aberrant control of programmed cell death plays a differential role in solid tumor and leukemia pathogenesis.

    Topics: Animals; Apoptosis; Cholecalciferol; Disease-Free Survival; fas Receptor; Female; Genes, Tumor Suppressor; Leukemia, Promyelocytic, Acute; Mammary Neoplasms, Experimental; Mice; Mice, Mutant Strains; Mice, Transgenic; Neoplasm Proteins; Nuclear Proteins; Oncogene Proteins, Fusion; Promyelocytic Leukemia Protein; Transcription Factors; Tumor Suppressor Proteins

2001
Acquisition of oncogenic potential by RAR chimeras in acute promyelocytic leukemia through formation of homodimers.
    Molecular cell, 2000, Volume: 5, Issue:5

    The t(15;17) chromosomal translocation in acute promyelocytic leukemia (APL) generates the PML-RARalpha fusion protein. The recruitment of nuclear receptor corepressor SMRT/N-CoR and subsequent repression of retinoid target genes is critical for the oncogenic function of PML-RARalpha. Here we show that the ability of PML-RARalpha to form homodimers is both necessary and sufficient for its increased binding efficiency to corepressor and inhibitory effects on hormonal responses in myeloid differentiation. We further provide evidence that altered stoichiometric interaction of SMRT with PML-RARalpha homodimers may underlie these processes. Finally, we demonstrate that a RXR AF2 mutant recapitulates many biochemical and functional properties of PML-RARalpha. Taken together, our results provide an example that altered dimerization of a transcription factor can be directly linked to cellular transformation and implicate dimerization interfaces of oncogenes as potential drug targets.

    Topics: Cell Differentiation; Cell Transformation, Neoplastic; Cholecalciferol; Dimerization; DNA-Binding Proteins; Gene Expression Regulation, Leukemic; Leukemia, Promyelocytic, Acute; Models, Genetic; Monocytes; Neoplasm Proteins; Nuclear Receptor Co-Repressor 2; Oncogene Proteins, Fusion; Protein Binding; Receptors, Retinoic Acid; Recombinant Fusion Proteins; Repressor Proteins; Retinoid X Receptors; Signal Transduction; Transcription Factors; Transcription, Genetic; Translocation, Genetic; Tretinoin

2000
Induction of differentiation in U-937 and NB4 cells is associated with inhibition of tissue factor production.
    European journal of haematology, 1999, Volume: 63, Issue:2

    Tissue factor (TF) production is under strict control in mature monocytic cells. However, constitutive expression of TF can be found in myelomonocytic cells and in haematopoietic cells arrested at an early stage of differentiation. In this paper we show that TF expression is down-regulated during the monocyte/granulocyte differentiation process, using the human monoblastic U-937 and the acute promyelocytic leukaemia NB4 cell lines as models. Expression of TF mRNA, protein and procoagulant activity (PCA) was constitutively high in untreated cells. Exposure of U-937 cells to 1alpha,25-dihydroxycholecalciferol (VitD3) and all-trans retinoic acid (ATRA) resulted in down-regulation of TF expression and PCA. In NB4 cells induction by ATRA, but not VitD3, resulted in the down-regulation of TF expression and PCA. Consistent with this, induction of terminal differentiation, as confirmed by the expression of differentiation associated antigens and cell cycle arrest, was inversely correlated to TF expression in U-937 and NB4 cells. Moreover, terminally differentiated U-937 cells retained the capacity to respond to inflammatory mediators, i.e. lipopolysaccharide and interferon-gamma, by a rapid increase in TF expression. In conclusion, we show that not only ATRA but also VitD3 is a potent suppressor of monocytic TF expression and thus might have potential clinical use for the treatment of coagulopathies.

    Topics: Cell Cycle; Cell Differentiation; Cholecalciferol; Gene Expression Regulation, Leukemic; Humans; Interferon-alpha; Interferon-gamma; Interleukin-1; Ionomycin; Leukemia, Promyelocytic, Acute; Lipopolysaccharides; Neoplasm Proteins; RNA, Messenger; RNA, Neoplasm; Tetradecanoylphorbol Acetate; Thromboplastin; Tretinoin; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha; U937 Cells

1999
1alpha,25-dihydroxyvitamin D(3)-26,23-lactone analogs antagonize differentiation of human leukemia cells (HL-60 cells) but not of human acute promyelocytic leukemia cells (NB4 cells).
    FEBS letters, 1999, Oct-29, Volume: 460, Issue:2

    We examined the effects of two novel 1alpha,25-dihydroxyvitamin D(3)-26,23-lactone (1alpha,25-(OH)(2)D(3)-26,23-lactone) analogs on 1alpha,25(OH)(2)D(3)-induced differentiation of human leukemia HL-60 cells thought to be mediated by the genomic action of 1alpha, 25-dihydroxyvitamin D(3) (1alpha,25-(OH)(2)D(3)) and of acute promyelocytic leukemia NB4 cells thought to be mediated by non-genomic actions of 1alpha,25-(OH)(2)D(3). We found that the 1alpha,25-(OH)(2)D(3)-26,23-lactone analogs, (23S)-25-dehydro-1alpha-hydroxyvitamin D(3)-26,23-lactone (TEI-9647) and (23R)-25-dehydro-1alpha-hydroxyvitamin D(3)-26,23-lactone (TEI-9648), inhibited differentiation of HL-60 cells induced by 1alpha,25-(OH)(2)D(3). However, 1beta-hydroxyl diastereomers of these analogs, i.e. (23S)-25-dehydro-1beta-hydroxyvitamin D(3)-26, 23-lactone (1beta-TEI-9647) and (23R)-25-dehydro-1beta-hydroxyvitamin D(3)-26,23-lactone (1beta-TEI-9648), did not inhibit differentiation of HL-60 cells caused by 1alpha,25-(OH)(2)D(3). A separate study showed that the nuclear vitamin D receptor (VDR) binding affinities of the 1-hydroxyl diastereomers were about 200 and 90 times weaker than that of 1alpha-hydroxyl diastereomers, respectively. Moreover, none of these lactone analogs inhibited NB4 cell differentiation induced by 1alpha,25-(OH)(2)D(3). In contrast, 1beta,25-dihydroxyvitamin D(3) (1beta,25-(OH)(2)D(3)) and 1beta,24R-dihydroxyvitamin D(3) (1beta,24R-(OH)(2)D(3)) inhibited NB4 cell differentiation but not HL-60 cell differentiation. Collectively, the results suggested that 1-hydroxyl lactone analogs, i.e. TEI-9647 and TEI-9648, are antagonists of 1alpha,25-(OH)(2)D(3), specifically for the nuclear VDR-mediated genomic actions, but not for non-genomic actions.

    Topics: Calcitriol; Cell Differentiation; Cholecalciferol; HL-60 Cells; Humans; Lactones; Leukemia, Promyelocytic, Acute; Protein Binding; Receptors, Calcitriol; Response Elements; Tumor Cells, Cultured; Vitamin D

1999
The synergistic effect of simultaneous addition of retinoic acid and vitamin D3 on the in-vitro differentiation of human promyelocytic leukemia cell lines could be efficiently transposed in vivo.
    Medical hypotheses, 1998, Volume: 50, Issue:3

    Both human cell lines HL-60 and AML-193 exhibit a myeloblastic and promyelocytic morphology, respectively, but may be regarded as bipotent leukemic precursors. They can be triggered to differentiate to either granulocytes or monocytes upon retinoic acid (RA) or 1,25-dihydroxyvitamin D (D3) addition, respectively. We have investigated the effect of combined addition of these chemical inducers on the in-vitro differentiation of both cell lines. RA and D3 added together exert synergistic effects on the in-vitro maturation of these myeloid cell lines. Interestingly, the additive effects were lost if the cells were incubated with the inducers added at sequential times. The synergistic effect could be transposed in vivo and could be clinically significant in the treatment of the promyelocytic leukemia. This clinical strategy may help to prevent retinoic acid resistance or to overcome it in patients relapsed after RA therapy and usually unresponsive to a reinduction therapy with RA alone.

    Topics: Cell Differentiation; Cholecalciferol; Drug Resistance; Drug Synergism; HL-60 Cells; Humans; Leukemia, Promyelocytic, Acute; Models, Biological; Tretinoin; Tumor Cells, Cultured

1998
Induction of the differentiation of HL-60 promyelocytic leukemia cells by nonsteroidal anti-inflammatory agents in combination with low levels of vitamin D3.
    Leukemia research, 1998, Volume: 22, Issue:2

    Previous experiments have shown that a variety of agents that interfere with the activity of the transcription factor NF-kB significantly enhanced the differentiation of HL-60 leukemia cells when combined with low levels of the monocytic/macrophagic differentiating agent vitamin D3. These include an antisense phosphorothioate oligonucleotide to the Rel A subunit of NF-kB, vitamin E and other antioxidants, and curcumin. Acetylsalicylic acid and other nonsteroidal anti-inflammatory agents represent another group of agents that have been reported to inhibit NF-kB at serum levels approximating those obtained during long-term therapy of chronic inflammatory states. To determine whether nonsteroidal anti-inflammatory agents also were capable of enhancing the differentiation of HL-60 leukemia cells produced by vitamin D3, we measured the effects of a variety of nonsteroidal anti-inflammatory agents on the maturation of HL-60 cells produced by low levels of vitamin D3. Acetylsalicylic acid by itself had no significant effect on the differentiation of HL-60 cells; however, this agent markedly increased the degree of differentiation produced by low levels of vitamin D3. Furthermore, a variety of other nonsteroidal anti-inflammatory agents of different chemical classes exhibited similar enhancements of the maturation of HL-60 cells when combined with vitamin D3. An analogous increase in the differentiation of HL-60 cells was also obtained by combination of several nonsteroidal anti-inflammatory agents with the granulocytic inducing agent, retinoic acid, but not with dimethylsulfoxide. The nonsteroidal anti-inflammatory agents also enhanced the differentiation of HL-60 cells when combined with vitamin D analogs which share the receptor binding properties of vitamin D3; however, a vitamin D analog which caused significant calcium mobilization, but was less effective in receptor binding than vitamin D3, did not induce the differentiation of HL-60 cells in the presence or absence of anti-inflammatory agents. The findings suggest that the nonsteroidal anti-inflammatory agents may have utility in the treatment of acute promyelocytic leukemia when used with the D vitamins or retinoic acid.

    Topics: Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Cell Differentiation; Cholecalciferol; Drug Interactions; HL-60 Cells; Humans; Leukemia, Promyelocytic, Acute

1998
Opposite effects of the acute promyelocytic leukemia PML-retinoic acid receptor alpha (RAR alpha) and PLZF-RAR alpha fusion proteins on retinoic acid signalling.
    Molecular and cellular biology, 1997, Volume: 17, Issue:8

    Fusion proteins involving the retinoic acid receptor alpha (RAR alpha) and the PML or PLZF nuclear protein are the genetic markers of acute promyelocytic leukemias (APLs). APLs with the PML-RAR alpha or the PLZF-RAR alpha fusion protein are phenotypically indistinguishable except that they differ in their sensitivity to retinoic acid (RA)-induced differentiation: PML-RAR alpha blasts are sensitive to RA and patients enter disease remission after RA treatment, while patients with PLZF-RAR alpha do not. We here report that (i) like PML-RAR alpha expression, PLZF-RAR alpha expression blocks terminal differentiation of hematopoietic precursor cell lines (U937 and HL-60) in response to different stimuli (vitamin D3, transforming growth factor beta1, and dimethyl sulfoxide); (ii) PML-RAR alpha, but not PLZF-RAR alpha, increases RA sensitivity of hematopoietic precursor cells and restores RA sensitivity of RA-resistant hematopoietic cells; (iii) PML-RAR alpha and PLZF-RAR alpha have similar RA binding affinities; and (iv) PML-RAR alpha enhances the RA response of RA target genes (those for RAR beta, RAR gamma, and transglutaminase type II [TGase]) in vivo, while PLZF-RAR alpha expression has either no effect (RAR beta) or an inhibitory activity (RAR gamma and type II TGase). These data demonstrate that PML-RAR alpha and PLZF-RAR alpha have similar (inhibitory) effects on RA-independent differentiation and opposite (stimulatory or inhibitory) effects on RA-dependent differentiation and that they behave in vivo as RA-dependent enhancers or inhibitors of RA-responsive genes, respectively. Their different activities on the RA signalling pathway might underlie the different responses of PML-RAR alpha and PLZF-RAR alpha APLs to RA treatment. The PLZF-RAR alpha fusion protein contains an approximately 120-amino-acid N-terminal motif (called the POZ domain), which is also found in a variety of zinc finger proteins and a group of poxvirus proteins and which mediates protein-protein interactions. Deletion of the PLZF POZ domain partially abrogated the inhibitory effect of PLZF-RAR alpha on RA-induced differentiation and on RA-mediated type II TGase up-regulation, suggesting that POZ-mediated protein interactions might be responsible for the inhibitory transcriptional activities of PLZF-RAR alpha.

    Topics: Cell Differentiation; Cell Line; Cholecalciferol; Dimethyl Sulfoxide; DNA-Binding Proteins; Gene Expression Regulation; Granulocytes; HL-60 Cells; Humans; Kruppel-Like Transcription Factors; Leukemia, Promyelocytic, Acute; Monocytes; Mutation; Neoplasm Proteins; Oncogene Proteins, Fusion; Promyelocytic Leukemia Zinc Finger Protein; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Retinoic Acid Receptor gamma; RNA, Messenger; Signal Transduction; Transcription Factors; Transforming Growth Factor beta; Transglutaminases; Tretinoin

1997
Common defects of different retinoic acid resistant promyelocytic leukemia cells are persistent telomerase activity and nuclear body disorganization.
    Differentiation; research in biological diversity, 1997, Volume: 61, Issue:5

    The acute promyelocytic leukemia (APL) t(15;17) rearrangement fuses the promyelocytic leukemia (PML) gene to the retinoic acid receptor-alpha (RAR alpha). There is expression of the chimeric transcript, PML/RAR alpha, in these APL cells. These clinical APL cases respond to the differentiation agent all-trans retinoic acid (ATRA) with complete but not durable remissions because ATRA resistance develops. The NB4 APL cell line expresses PML/RAR alpha and responds to the growth inhibitory and differentiation-inducing signals of ATRA. To identify mechanisms responsible for ATRA resistance in APL, ATRA-resistant NB4 cell lines were derived from parental NB4 cells using different strategies. These lines were resistant to the growth inhibition and differentiation effects of ATRA. ATRA-resistant cells were isolated as a de novo resistant line from parental NB4 cells (NB4-R1), following chemical mutagenization and selection in ATRA (NB4-R2), or after chronic selection in ATRA (NB4-R3). Common defects linked to this ATRA resistance were found. When cultured in ATRA, these resistant cells still express PML, RAR alpha, and PML/RAR alpha proteins. Sequence abnormalities were not detected in the RAR alpha DNA binding domains cloned from a representative RA-resistant NB4 line. In ATRA-sensitive but not ATRA-resistant NB4 cells, ATRA down-regulated retinoid X receptor-alpha (RXR alpha) expression, a known marker of ATRA response in parental NB4 cells. Notably, engineered overexpression of RXR alpha in ATRA-sensitive NB4 cells did not block ATRA-mediated growth suppression. ATRA treatment of these resistant NB4 lines did not signal a decline in telomerase activity or reorganization of PML-associated nuclear bodies, but both events occurred in ATRA-sensitive NB4 cells. These ATRA-resistant NB4 lines are not fully differentiation-defective, since monocytic maturation was induced following treatment with phorbol 12-myristate 13-acetate (PMA) and 1,25 dihydroxy vitamin D3 (vitamin D3). Notably, induced monocytic differentiation of these distinct ATRA-resistant APL lines markedly repressed telomerase activity. Thus, this study suggests that persistent telomerase activity and nuclear body disorganization are linked to ATRA resistance in APL.

    Topics: Antineoplastic Agents; Binding Sites; Blotting, Western; Carcinogens; Cell Differentiation; Cell Division; Cell Nucleus; Cholecalciferol; Clone Cells; DNA, Neoplasm; Drug Resistance, Neoplasm; Humans; Leukemia, Promyelocytic, Acute; Methylnitronitrosoguanidine; Polymerase Chain Reaction; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Telomerase; Tetradecanoylphorbol Acetate; Transcription, Genetic; Tretinoin; Tumor Cells, Cultured

1997
Overexpression of poly(ADP-ribose) polymerase promotes cell cycle arrest and inhibits neutrophilic differentiation of NB4 acute promyelocytic leukemia cells.
    Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research, 1996, Volume: 7, Issue:1

    The t(15;17) translocation causes a disruption of the retinoic acid receptor alpha (RAR-alpha) and allows for the expression of the PML-RAR alpha fusion protein considered to be responsible for the differentiation block in acute promyelocytic leukemia (APL). Patients being treated with all-trans retinoic acid (ATRA) undergo remission due to the differentiation of leukemic cells to functional neutrophils but relapse due to subsequent ATRA resistance. Our group has shown recently that NB4 cells, the only in vitro model of APL, are capable of monocytic differentiation in response to 1,25-dihydroxyvitamin D3 and 12-O-tetradecanoylphorbol-13-acetate in addition to the neutrophilic differentiation response that occurs with ATRA treatment. Poly(ADP-ribose) polymerase (PARP) is a ubiquitous protein that plays a role in DNA metabolism and repair. We have shown that, unlike HL-60 cells, NB4 cells completely down-regulate PARP in the neutrophilic lineage and up-regulate PARP 90-fold in the monocytic lineage. To ascertain whether PARP is an active participant in the bipotent differentiation of APL cells, NB4 cells were transiently transfected by lipid-mediated gene transfer with the human PARP gene under the control of the human metallothionein promoter. A 4-fold overexpression of PARP, in response to 8 microM CdCl2, promoted arrest of NB4 cells in the S phase of the cell cycle. Overexpression of PARP alone had no effect on cell viability or induction of phenotypic markers in the monocytic or neutrophilic lineages. However, increased PARP expression did result in an increase in the number of cells in the subdiploid population likely to include apoptotic cells. Overexpression of PARP, alone with 12-O-tetradecanoylphorbol-13-acetate (200 nM), 1,25-dihydroxyvitamin D3 (200 nM), or a suboptimal dose of the combined agents, did not alter the expected monocytic differentiation marker profile over cells transfected with control plasmid (pSV2Neo). In contrast, PARP overexpression blocked the appearance of phenotypic markers of terminally differentiated neutrophils in 85% of the transfected population in response to 1 microM ATRA. Comparable to wild-type NB4 cells, 90% of cells transfected with pSV2Neo developed neutrophilic differentiation markers (nitroblue tetrazolium-positive and multi-lobed nuclei) in response to 1 microM ATRA. These data suggest that overexpression of PARP arrests APL cells and blocks ATRA-induced terminal neutrophilic differentiation. We propose that n

    Topics: Cell Cycle; Cell Differentiation; Cell Division; Cholecalciferol; Gene Expression; Humans; Leukemia, Promyelocytic, Acute; Neutrophils; Plasmids; Poly(ADP-ribose) Polymerases; Sensitivity and Specificity; Tetradecanoylphorbol Acetate; Transfection; Tretinoin; Tumor Cells, Cultured

1996
Combined vitamin D3/retinoic acid induction of human promyelocytic cell lines: enhanced phagocytic cell maturation and hybrid granulomonocytic phenotype.
    Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research, 1995, Volume: 6, Issue:5

    Studies on the effect of retinoic acid (RA) and 1,25-dihydroxyvitamin (D3) on the differentiation of leukemic cells have provided insight into the cellular and molecular mechanisms underlying hematopoietic cell differentiation. We have evaluated the combined effect of these chemical inducers on the differentiation of HL-60 and AML-193 promyelocytic leukemia cell lines. Simultaneous RA+D3 addition potentiated leukemic cell maturation up to mature phagocytic cells. Interestingly, AML-193 cells induced with D3 and RA displayed a typical neutrophilic morphology while exhibiting properties specific to monocytic cells, e.g., high expression of CD14 membrane antigen, capacity to bind bacterial lipopolysaccharide, and monocytic-specific esterase activity; this hybrid granulomonocytic (GM) phenotype was not observed upon initial incubation with one inducer and later addition of the other. Parallel control studies were performed with purified normal GM progenitors, triggered by interleukin 3+GM-colony-stimulating factor (CSF) in FCS-rich or -free clonogenic culture, by GM-CSF+M-CSF in FCS-rich clonogenic culture, and by M-CSF in liquid suspension culture. The progenitors grown in the first condition generate exclusively G clones, even upon addition of D3 and/or RA. The progenitors grown in the second and third culture conditions generate either G and M clones (second culture condition) or a population of cells composed by a majority of monocytes (third culture condition); the D3 addition did not modify this differentiation pattern, whereas RA or RA+D3 addition elicited a marked inhibition of monocytic differentiation. These observations suggest that the development of a hybrid GM phenotype is restricted to the progeny of bipotent GM leukemic precursors.

    Topics: Antigens, CD; Cell Differentiation; Cholecalciferol; Granulocytes; Hematopoietic Stem Cells; Humans; Leukemia, Monocytic, Acute; Leukemia, Promyelocytic, Acute; Monocytes; Phagocytes; Phenotype; Tretinoin; Tumor Cells, Cultured

1995
Antagonistic activity of 24-oxa-analogs of vitamin D.
    Steroids, 1995, Volume: 60, Issue:6

    24-Oxa-vitamin D3 (24-oxa-D3) and 24-oxa-1 alpha-hydroxyvitamin D3 were designed as possible inhibitors of the vitamin D metabolic activation pathway. Their affinity for the vitamin D receptor (from pig intestine) and human vitamin binding protein were reduced, and their potency to induce cell differentiation of human leukemia cells (HL 60) or osteosarcoma cells (MG 63) was markedly reduced (19% and 3%, respectively), in comparison with calcitriol. A single or chronic injection of 24-oxa-D3 had no biological activity, whereas chronic administration of 24-oxa-1 alpha-hydroxy-D3 showed weak agonist activity in rachitic chicks. When the 24-oxa-D3 was given prior to a single injection of vitamin D3, lower values of serum calcium (64% of the value obtained in vitamin D-treated animals), osteocalcin (52%), 25-(OH)D3 (45%) and duodenal calbindin-D 28K (9.4%) were found. When given chronically in a 100-fold more excess no clear antagonistic effects were observed. 24-Oxa-D3 is thus a new metabolic weak antagonist of vitamin D3, but adding a hydroxyl group at C-1 creates a weak agonist.

    Topics: Animals; Calcitriol; Calcium; Cell Differentiation; Chickens; Cholecalciferol; Humans; Leukemia, Promyelocytic, Acute; Osteosarcoma; Receptors, Calcitriol; Swine; Tumor Cells, Cultured; Vitamin D; Vitamin D-Binding Protein

1995
RB phosphorylation in sodium butyrate-resistant HL-60 cells: cross-resistance to retinoic acid but not vitamin D3.
    Journal of cellular physiology, 1995, Volume: 163, Issue:3

    To examine the potential coupling between inducible cellular changes in RB (retinoblastoma) tumor suppressor protein phosphorylation and ability to G0 growth arrest and differentiate, HL-60 promyelocytic leukemia cells were cultured in incremental sodium butyrate (NaB) concentrations and thereby made resistant to the growth inhibitory effects of sodium butyrate, which normally induces G0 arrest and monocytic differentiation in wild type HL-60 cells. The resistant cells were also unable to differentiate in response to NaB, indicating that a regulatory function controlling both G0 growth arrest and differentiation had been affected. The induced resistance was not genetic in origin since the cells regained the ability to G0 arrest and differentiate after being recultured in medium free of sodium butyrate for only three days. The resistant cells had similar cell cycle phase durations as the original wild type cells. The resistant cells retained the ability to both G0 arrest and differentiate in response to 1,25-dihydroxy vitamin D3 (VD3), normally an inducer of G0 arrest and monocytic differentiation in wild type cells. However, they were cross-resistant to retinoic acid (RA), another ligand for the same steroid thyroid hormone receptor family, which induces G0 arrest and myeloid differentiation in wild type cells. The ability to G0 arrest and phenotypically differentiate in response to RA were both grossly impaired. Unlike wild type cells which undergo early down-regulation and then hypophosphorylation of the RB protein when induced to differentiate, in resistant cells, hypophosphorylation of RB in response to NaB was grossly retarded. These changes in RB protein occurred faster when the cells were treated with VD3. In contrast, the changes in RB phosphorylation occurred significantly slower when the cells were treated with RA. The results suggest a coupling between the ability to G0 growth arrest and phenotypically convert and the ability to hypophosphorylate RB.

    Topics: Butyrates; Butyric Acid; Cell Differentiation; Cholecalciferol; Drug Resistance; Humans; Leukemia, Promyelocytic, Acute; Phosphorylation; Resting Phase, Cell Cycle; Retinoblastoma Protein; Tretinoin; Tumor Cells, Cultured

1995
Vitamin D3 analogs: effect on leukemic clonal growth and differentiation, and on serum calcium levels.
    Leukemia research, 1995, Volume: 19, Issue:1

    In vitro, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) induces differentiation of HL-60 cells and inhibits their proliferation as well as the proliferation of leukemic cells from patients. In vivo, the survival of mice challenged with syngeneic leukemic cells is enhanced by treatment with 1,25(OH)2D3. Patients treated with 1,25(OH)2D3 develop hypercalcemia at a serum level of 2 x 10(-10) mol/l which is a concentration too low to achieve an antileukemic effect in vitro. Several interesting vitamin D3 analogs have recently been developed. We initially examined the effect of 1,25(OH)2-16ene-23yne-19-nor-26,27-F6-D3 and 24a,26a,27a-tri-homo-22,24-diene-1-alpha,25-(OH)2-D3 on clonal growth and differentiation of HL-60 cells. Each of the analogs had comparable effects on clonal growth with 50% inhibition (ED50) at concentrations of 0.2-0.5 x 10(-9) M; 1,25(OH)2D3 was about 20- to 50-fold less active in inhibiting growth. Differentiation was determined by induction of superoxide production, as measured by nitroblue tetrazolium (NBT) reduction and by expression of a macrophage-specific enzyme (alpha napthyl acetate esterase (ANAE)). The 24a,26a,27a-tri-homo-22,24-diene-1-alpha,25-(OH)2-D3 and 1,25(OH)2-16ene-23yne-19-nor-26,27-F6-D3 were about 5- to 14-fold more potent than 1,25(OH)2D3. The hypercalcemia inducing side-effects of these analogs and three other previously identified, extremely potent vitamin D3 compounds, as well as 1,25(OH)2D3, were studied. The analogs were administered intraperitoneally every other day (qod) for 5 weeks; serum was collected weekly and Ca2+ measured by atomic absorption spectrophotometry. The highest tolerated dose of each analog leaving all mice alive was for 1,25(OH)2D3: 0.25 micrograms; 1,25(OH)2-24a,26a,27a-tri-homo-22,24-diene-D3: 0.25 micrograms; and 1,25(OH)2-16ene-23yne-19-nor-26,27-F6-D3: 0.0625 micrograms. Another hexafluoro compound with potent abilities to induce differentiation (1,25(OH)2-16ene-23yne-26,27-F6-D3) was very toxic, all mice died in the second week while receiving 0.0625 micrograms qod. Prior studies showed that the most potent compound in inducing differentiation of HL-60 was 1,25(OH)2-20-epi-D3; but it is very toxic as only one mouse survived a dose of > or = 0.0125 micrograms qod for 5 weeks. 1,25(OH)2-16ene-23yne-D3 is an extremely active inducer of differentiation but, on the other hand, it has low potential to produce hypercalcemia; mice maintained normal serum calcium levels even while receiving 2 microg

    Topics: Animals; Bone Marrow; Bone Marrow Cells; Calcium; Cell Differentiation; Cell Division; Cholecalciferol; Clone Cells; Humans; Hypercalcemia; Leukemia, Promyelocytic, Acute; Mice; Mice, Inbred BALB C; Tumor Cells, Cultured

1995
Indomethacin potentiates the induction of HL60 differentiation to neutrophils, by retinoic acid and granulocyte colony-stimulating factor, and to monocytes, by vitamin D3.
    Leukemia, 1994, Volume: 8, Issue:4

    We have confirmed previous observations that HL60 cells treated with a combination of 10 nM retinoic acid (RA), and 30 ng/ml granulocyte colony-stimulating factor (G-CSF) differentiate efficiently towards neutrophils, as characterized by their growth arrest and acquisition of phagocytic ability. Such low concentrations of RA alone provoked only a small proportion of HL60 cells to differentiate, and G-CSF alone provoked no differentiation. In the presence of 30 microM indomethacin (an inhibitor of the enzyme cyclooxygenase that catalyses the first step of prostanoid synthesis), the onset of differentiation provoked by RA plus G-CSF was more rapid, but the final proportion of mature cells was unchanged. Indomethacin also potentiated the growth arrest and differentiation of cells in response to 10 nM RA alone. Although the potentiating effect of indomethacin on RA-induced differentiation occurred at several indomethacin and RA concentrations, it was only apparent when the RA concentration used was alone sufficient to induce a small proportion of cells to differentiate. Indomethacin shifted the G-CSF dose-response curve of cells treated with 10 nM RA to lower G-CSF concentrations. 1 alpha,25-dihydroxy vitamin D3 (VitD3) induces HL60 cells to differentiate to monocytes and indomethacin also potentiated the differentiation of HL60 cells in response to low doses of VitD3 5,8,11-eicosatriynoic acid, an inhibitor of 5-lipoxygenase and 12-lipoxygenase, neither potentiated neutrophil differentiation of HL60 cells, nor prevented indomethacin potentiation of the differentiation of RA-primed cells. Treatment of cells with dexamethasone, a steroid whose effects include inhibition of arachidonate mobilization by phospholipase A2, potentiated RA-primed neutrophil differentiation in a manner similar to indomethacin. These observations suggest that an arachidonate metabolite formed downstream of cyclooxygenase suppresses differentiation of HL60 cells both to neutrophils and monocytes, probably by inhibiting some event essential to commitment to differentiation.

    Topics: Arachidonic Acid; Cell Differentiation; Cholecalciferol; Dose-Response Relationship, Drug; Drug Synergism; Granulocyte Colony-Stimulating Factor; Humans; Indomethacin; Leukemia, Promyelocytic, Acute; Lipoxygenase; Neutrophils; Tretinoin; Tumor Cells, Cultured

1994
PML/RAR alpha+ U937 mutant and NB4 cell lines: retinoic acid restores the monocytic differentiation response to vitamin D3.
    Cancer research, 1994, Aug-15, Volume: 54, Issue:16

    We have analyzed the differentiation program of a U937 promonocytic leukemia clone transduced with the acute promyelocytic leukemia specific PML/RAR alpha fusion gene, the expression of which is under the control of the inducible metallothionine (MT) I promoter (MTPR9 clone). MTPR9 cells treated with Zn2+ hence exhibit levels of PML-RAR alpha protein as high as fresh acute promyelocytic leukemia blasts. In the absence of Zn2+, i.e., upon low level PML/RAR alpha expression, 1,25-dihydroxyvitamin D3 (D3) and particularly D3 plus transforming growth factor beta 1 (TGF-beta 1) induced terminal differentiation of MTPR9 cells (as observed in "wild-type" U937 cells), on the basis of morphology, membrane antigen pattern, and functional criteria. Conversely, in the presence of Zn2+, D3 and D3 plus TGF-beta 1 failed to induce terminal differentiation, as evaluated by the above parameters. Interestingly, retinoic acid (RA) treatment suppresses the differentiation blockade induced by high level PML-RAR alpha protein; indeed, Zn(2+)-treated MTPR9 cells incubated with RA plus D3 exhibited significant terminal monocytic maturation, comparable to that of cells treated with D3 alone or combined with RA in absence of Zn2+. Similar observations were made in NB4, a PML-RAR+ human acute leukemic line. As expected RA treatment of NB4 cells causes granulocytic differentiation. Interestingly, the cell line is only scarcely induced to mature monocytic cells by D3 or D3 plus TGF-beta 1 treatment, whereas it is effectively induced to monocytic maturation by combined treatment with D3 and RA. Accordingly, the rate of NB4 cell proliferation is only slightly affected by D3 or D3 plus TGF-beta 1 treatment, mildly inhibited by RA, and markedly decreased by D3 plus RA. These results indicate that in both U937 and NB4 cells high level PML/RAR alpha expression inhibits the monocytic terminal differentiation program triggered by D3 or D3 plus TGF-beta 1, whereas RA treatment effectively antagonizes this inhibitory PML-RAR alpha action and restores the D3 differentiative effect.

    Topics: Antigens, CD; Antigens, Differentiation, Myelomonocytic; Cell Differentiation; Cell Division; Cholecalciferol; Gene Expression Regulation, Leukemic; Humans; Leukemia, Promyelocytic, Acute; Lipopolysaccharide Receptors; Lipopolysaccharides; Neoplasm Proteins; Nuclear Proteins; Promyelocytic Leukemia Protein; Transcription Factors; Transfection; Transforming Growth Factor beta; Tretinoin; Tumor Cells, Cultured; Tumor Suppressor Proteins; Zinc

1994
Relationship of calcitonin mRNA expression to the differentiation state of HL 60 cells.
    Leukemia & lymphoma, 1994, Volume: 13, Issue:5-6

    Raised plasma levels of immunoreactive human calcitonin (ihCT) can be found in patients with myeloid leukemia and seem to indicate a poor prognosis. High levels were found in acute undifferentiated and acute myeloblastic leukemia. To test whether CT expression could be a marker of myeloid differentiation, we used the promyelocytic leukemia cell line HL 60 which also expresses ihCT as a model system for myeloid differentiation. Exponentially growing HL 60 cells as well as differentiation induced HL 60 cells expressed a single 1.0 Kb CT transcript. The induction of HL 60 cell differentiation along the granulocytic lineage by DMSO or HMBA had no effect on the level of CT transcripts. Induction of monocytic/macrophagic differentiation by TPA resulted in a transient, about 10-fold elevated expression of CT steady state mRNA after 24 h. In contrast to TPA, induction of HL 60 cell differentiation along the monocytic pathway by Vit D3 had no detectable effect on the level of the CT in RNA expression at corresponding time points. These findings suggest that the transient induction of CT steady state mRNA expression by TPA is rather a direct effect of the phorbol ester than commitment along the monocytic line of differentiation.

    Topics: Acetamides; Calcitonin; Calcitonin Gene-Related Peptide; Cell Differentiation; Cell Division; Cholecalciferol; Dimethyl Sulfoxide; Gene Expression; Humans; Leukemia, Promyelocytic, Acute; Macrophages; Models, Biological; Monocytes; Phenotype; RNA, Messenger; Staining and Labeling; Tetradecanoylphorbol Acetate; Tumor Cells, Cultured

1994
Retinoic acid is required for and potentiates differentiation of acute promyelocytic leukemia cells by nonretinoid agents.
    Blood, 1994, Oct-01, Volume: 84, Issue:7

    Patients with acute promyelocytic leukemia (APL) associated with the t(15;17) translocation and fusion of the promyelocytic leukemia (PML) and retinoic acid receptor-alpha (RAR-alpha) genes achieve complete remission but not cure with all-trans retinoic acid (RA), NB4, a cell line derived from a patient with t(15;17) APL that undergoes granulocytic differentiation when treated with pharmacologic doses of RA, was used as a model for differentiation therapy of APL. We found that NB4 cells are resistant to differentiation by nonretinoid inducers such as hexamethylene bisacetamide (HMBA), butyrates, vitamin D3, or hypoxanthine, all of which can induce differentiation in the commonly used HL60 leukemia cell line. Preexposure of NB4 cells to low concentrations of RA for a period as short as 30 minutes abolished resistance to nonretinoids and potentiated differentiation. Sequential RA and HMBA treatment yielded maximal differentiation by 3 days of drug exposure, whereas the effect of RA alone peaked after 6 days and yielded a smaller percentage of differentiated cells. RA also reversed NB4 cell resistance to butyrates and allowed for synergistic differentiation by these agents. Pretreatment with HMBA before exposure to RA failed to stimulate differentiation. Sequential RA/HMBA treatment also markedly increased the extent of differentiation of primary cultures of bone marrow and peripheral blood mononuclear cells from three APL patients. In one case RA/HMBA treatment overcame resistance to RA in vitro. Together, these results suggest that intermittent low doses of RA followed by either HMBA or butyrates may be a useful combination in the treatment of APL. This clinical strategy may help prevent or overcome RA resistance in APL.

    Topics: Acetamides; Butyrates; Cell Differentiation; Cholecalciferol; Cytarabine; Drug Synergism; Humans; In Vitro Techniques; Leukemia, Promyelocytic, Acute; Tretinoin; Tumor Cells, Cultured

1994
Synthesis of proteoglycan during HL-60 cell differentiation.
    Biochemical and biophysical research communications, 1994, Sep-30, Volume: 203, Issue:3

    Newly synthesized proteoglycans (PG) in proliferating HL-60 cells were labeled with [35S]-sulfate and fractionated on DEAE-cellulose columns. Peak fractions were digested with chondroitinase ABC and separated by paper chromatography. Chondroitin sulfate was identified as the major PG. Treatment of cells with 16 nM TPA resulted in a 1.8-fold increase in total sulfate incorporation into PG, a shift in its location from the cellular to the extracellular compartment, and an increase in the total charge of PG (based on the profile of elution from DEAE-cellulose columns), compared to controls. Incorporation of [3H]-glucosamine into cellular PG was markedly decreased in TPA-treated cells; the sulfate/glucosamine ratio showed a 13.5-fold decrease in the newly synthesized cellular PG. The sulfate/glucosamine ratio, however, was increased by 7.6-fold in secreted PG.

    Topics: Cell Differentiation; Cell Division; Cell Line; Cholecalciferol; Chromatography, DEAE-Cellulose; Chromatography, Gel; Glucosamine; Humans; Leukemia, Promyelocytic, Acute; Proteoglycans; Sulfates; Sulfur Radioisotopes; Tetradecanoylphorbol Acetate; Tritium; Tumor Cells, Cultured

1994
Downregulation of Wilms' tumor gene (wt1) during myelomonocytic differentiation in HL60 cells.
    Blood, 1994, Apr-01, Volume: 83, Issue:7

    The putative Wilms' tumor-suppressor gene (wt1) encodes a zinc finger DNA binding protein that functions as a transcription repressor. The wt1 gene expression corresponds to kidney development, suggesting a role for this gene in nephroblast differentiation. Here we show that wt1 mRNA expression was downregulated during terminal differentiation of promyelocytic HL60 cells. When HL60 cells were induced to differentiate to granulocytes by dimethyl sulfoxide (DMSO) or retinoic acid (RA), a marked downregulation in the levels of wt1 transcripts was found. The wt1 transcripts were also downregulated in HL60 cells during differentiation to monocytes by vitamin D3 or 12-o-tetradecanoyl-phorbol-13-acetate. Nuclear run-on transcription studies showed the transcriptional rate of wt1 gene was not significantly altered during DMSO-induced granulocytic differentiation, suggesting the downregulation was mostly caused by posttranscriptional modification. Importantly, wt1 transcripts were not significantly altered in K562 cells by treatments with DMSO or RA, which do not induce differentiation of K562 cells. These findings suggest that wt1 gene expression may be downregulated as a differentiation-linked event in HL60 cells.

    Topics: Base Sequence; Cell Differentiation; Cholecalciferol; Dimethyl Sulfoxide; DNA-Binding Proteins; Down-Regulation; Genes, Retinoblastoma; Genes, Wilms Tumor; Humans; Leukemia, Promyelocytic, Acute; Molecular Sequence Data; Tetradecanoylphorbol Acetate; Transcription, Genetic; Tretinoin; Tumor Cells, Cultured; WT1 Proteins

1994
1,25(OH)2-16ene-vitamin D3 is a potent antileukemic agent with low potential to cause hypercalcemia.
    Leukemia research, 1994, Volume: 18, Issue:6

    Compounds that induce cancer cells to differentiate are clinically effective for several types of malignancies. The 1,25-dihydroxyvitamin D3[1,25(OH)2D3(C)] induces leukemic cells, including HL-60, to differentiate and/or no longer proliferate, but it causes hypercalcemia. Development of vitamin D analogs that are more potent in their abilities to affect leukemic cells without causing greater hypercalcemia, may be useful therapeutically. A novel analog [1,25(OH)2-16ene-D3(HM)] has a double bond between C-16 and C-17; it appears to be an extremely effective antileukemic agent with the same or fewer effects on serum calciums. We define the potency of this compound and compare it with seven, previously reported, potent analogs of 1,25(OH)2D3. HM inhibited clonal growth of HL-60 cells by 50% at 1.5 x 10(-11) M. This was about equipotent to 1,25(OH)2-16ene-23yne-D3(V), about 100-fold more potent than many of the other analogs, and 1000-fold more potent than 1,25(OH)2D3. The rank order of leukemic inhibitory activity was: 1,25(OH)2-16ene-D3(HM) > or = 1,25(OH)2- 16ene-23yne-D3(V) > 1,25(OH)2-23ene-D3(EX) = 1,24(OH)2-22ene-24-cyclopropyl-D3(BT) = 22-oxa- 1,25(OH)2D3(EU) = 1,25(OH)2-24-homo-D3(ER) > 1,25(OH)2D3(C) > 1,25(OH)2-24- dihomo-D3(ES). The rank order of their effects on induction of differentiation of HL-60 cells, as measured by superoxide production and nonspecific esterase activity, was similar to their antiproliferative activities. In contrast, each analog slightly stimulated proliferation of normal human myeloid clonal growth. Serum calcium levels were the same or slightly less when either 1,25(OH)2-16ene-D3(HM) or 1,25(OH)2D3 (0.0625, 0.125, or 0.25 microgram) was given intraperitoneally to mice for 5 weeks. HM bound to 1,25(OH)2D3 receptors about 1.5-fold more avidly than 1,25(OH)2D3. In fact, this vitamin D3 appears to be the most avid binder to 1,25(OH)2D3 receptors that has been identified to date. In contrast, HM had a greater than 50-fold lower affinity for the D-binding proteins as compared with 1,25(OH)2D3, thus increasing the availability of the compound for target tissues. Further differentiation experiments showed that HM was more potent than 1,25(OH)2D3 in the presence of serum, but was equipotent in serum-free conditions. Taken together, our experiments suggest that 1,25(OH)2-16ene-D3(HM) may be more potent than 1,25(OH)2D3(C) because of its higher affinity to the 1,25(OH)2D3 receptors and its low affinity to the D-binding protein prese

    Topics: Antineoplastic Agents; Calcitriol; Calcium; Cell Differentiation; Cell Division; Cell Line; Cholecalciferol; Dose-Response Relationship, Drug; Humans; Hypercalcemia; Leukemia, Promyelocytic, Acute; Molecular Structure; Structure-Activity Relationship; Tumor Cells, Cultured; Tumor Stem Cell Assay; Vitamin D-Binding Protein

1994
The PML-RAR alpha gene product of the t(15;17) translocation inhibits retinoic acid-induced granulocytic differentiation and mediated transactivation in human myeloid cells.
    Oncogene, 1994, Volume: 9, Issue:2

    Acute promyelocytic leukemia (APL) is characterized by an arrest of granulocytic differentiation and a reciprocal t(15;17) translocation fusing the PML gene to the retinoic acid receptor alpha (RAR alpha) gene. PML was recently identified as a potential transcription factor. In non hematopoietic cells, the transfected PML-RAR alpha product binds all trans retinoic acid and exhibits altered transactivating properties when compared with RAR alpha. A major question raised by these observations is whether PML-RAR alpha contributes to the inhibition of myeloid differentiation. We find that in myeloid cell lines responsive to retinoic acid, PML-RAR alpha blocks retinoic acid mediated transactivation and totally abrogates the retinoic acid mediated granulocytic differentiation. These findings strongly suggest that PML-RAR alpha may, by blocking normal retinoic acid dependent myeloid differentiation, participate in the leukemogenesis of APL. The fact that high doses of all-trans retinoic acid relieve the inhibitory effect of PML-RAR alpha corroborates the therapeutic effect of all-trans retinoic acid in APL patients.

    Topics: Base Sequence; Bone Marrow; Bone Marrow Cells; Cell Differentiation; Cell Line; Cholecalciferol; Chromosomes, Human, Pair 15; Chromosomes, Human, Pair 17; DNA, Neoplasm; Dose-Response Relationship, Drug; Granulocytes; Humans; Leukemia, Promyelocytic, Acute; Molecular Sequence Data; Neoplasm Proteins; Nuclear Proteins; Promyelocytic Leukemia Protein; Receptors, Retinoic Acid; Recombinant Fusion Proteins; Retinoic Acid Receptor alpha; Transcription Factors; Transcriptional Activation; Transfection; Translocation, Genetic; Tretinoin; Tumor Cells, Cultured; Tumor Suppressor Proteins

1994
A dual block to cell cycle progression in HL60 cells exposed to analogues of vitamin D3.
    Cell proliferation, 1994, Volume: 27, Issue:1

    The physiologically active form of vitamin D3, 1,25-dihydroxy-vitamin D3 (1,25(OH)2D3), induces differentiation of several types of myeloid leukaemia cells. The acquisition of monocyte-like phenotype is accompanied by slower progression through the cell cycle, and G1 block has been reported to be the basis of this effect. It is shown here that human promyelocytic leukaemia HL60 cells treated with analogues of vitamin D3 which are potent inducers of monocytic differentiation have an additional cell cycle block. Exposure to 10(-7) M 1,25(OH)2D3 or 1,25-(OH)2-16-ene-D3 resulted in monocytic differentiation and the expected G1 block evident at approximately 48 h in a rapidly differentiating variant of HL60 cells (HL60-G), and at 96 h in the more slowly differentiating HL60-240 cells. In addition, a G2+M block was noted at approximately 72 h in HL60-G and HL60-240 cells. Exposure to vitamin D3 analogues also markedly increased the number of dikaryons, suggesting that cytokinesis was impaired more than karyokinesis. Treatment with a third analogue 25-hydroxy-16,23-diene-D3 produced little differentiation and had minimal effects on the cell cycle parameters. These findings indicate that vitamin D3 analogues regulate cell proliferation by control of the transition of G1 and G2+M phases, reminiscent of the cdc2/CDK2 type of cell cycle control.

    Topics: Antineoplastic Agents; Azure Stains; Calcitriol; Cell Cycle; Cell Differentiation; Cell Division; Cholecalciferol; G1 Phase; G2 Phase; Humans; Leukemia, Promyelocytic, Acute; Mitosis; Monocytes; Tumor Cells, Cultured

1994
Modulation of gene expression in the acute promyelocytic leukemia cell line NB4.
    Leukemia, 1993, Volume: 7, Issue:11

    The human leukemic cell line NB4 was derived from a patient with acute promyelocytic leukemia and is characterized by a specific 15;17 chromosomal translocation. We analyzed the response of NB4 and HL-60 cells to the biomodulators all-transretinoic acid (ATRA), vitamin D3 (Vit D3) and the protein kinase C agonists bryostatin 1 (Bryo 1) and phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA). HL-60 cells were used for comparison being arrested at the myeloblastic-promyelocytic stage, but lacking the t(15;17) abnormality. In most experiments Vit D3 was only weakly or not at all effective. The other three reagents effectively slowed or stopped the proliferation of the cells in suspension. Associated with this proliferation arrest was the cell differentiation along the myeloid cell lineages: ATRA modulated morphological features indicative of granulocytic differentiation; Bryo 1 and TPA caused also distinct morphological changes. The inducers up-regulated the expression of CD11b (without changing the surface expression of other markers, e.g. CD13, CD14, CD15, CD33, CD68, HLA-DR) and completely down-regulated the originally strong expression of myeloperoxidase and c-myc at the mRNA level. Thus, ATRA- or protein kinase C activator-induced differentiation involved changes associated with maturational processes. Induction of terminal differentiation of leukemic cells by physiological or pharmacological modulators may be able to control the growth of the malignant cells and has therapeutic implications.

    Topics: Antigens, CD; Bryostatins; CD11 Antigens; Cell Differentiation; Cell Division; Cholecalciferol; Down-Regulation; Gene Expression Regulation, Leukemic; Genes, myc; Humans; Lactones; Leukemia, Promyelocytic, Acute; Macrolides; Peroxidase; RNA, Messenger; Tetradecanoylphorbol Acetate; Tretinoin; Tumor Cells, Cultured

1993
Expression and modulation of annexin VIII in human leukemia-lymphoma cell lines.
    Leukemia research, 1993, Volume: 17, Issue:11

    Annexin VIII is a calcium- and phospholipid-binding protein with anticoagulant activity. Annexin VIII mRNA was found to be specifically expressed in acute promyelocytic leukemia (APL) cells; it was not found in other types of acute myeloid leukemia (AML) nor in lymphoid malignancies. Using Northern blot analysis we investigated annexin VIII expression in 142 continuous human leukemia and lymphoma cell lines at the mRNA level. While the only APL cell line, NB-4, was indeed positive, other cell lines also displayed annexin VIII mRNA: 4/22 myeloid cell lines, 8/23 monocytic cell lines, 2/8 megakaryoblastic cell lines, 5/26 lymphoma-derived cell lines, 2/10 myeloma cell lines and 1/44 lymphoid leukemia cell lines. The strongest expression was seen in NB-4 and in the Hodgkin's disease derived cell line HDLM-2. Treatment of NB-4 cells with all-trans retinoic acid (ATRA) or the phorbol ester TPA induced terminal differentiation and down-regulated annexin VIII mRNA expression rapidly within a few hours; vitamin D3 was ineffective in this regard; the protein kinase C activator Bryostatin 1 up-regulated the expression. A panel of initially negative cell lines could not be induced by any of these biomodulators to transcribe annexin VIII. The half-life (T1/2) of annexin VIII mRNA was about 3-4 h using actinomycin D as transcription inhibitor. Treatment with ATRA or TPA prior to exposure to actinomycin shortened the T1/2 to 2 h while Bryostatin 1 extended it to 6h. As 21/141 non-APL cell lines were positive, annexin VIII cannot be used as a marker gene for APL cells; however, it might be associated with myelomonocytic or erythro-megakaryoblastic precursor cells. Annexin VIII gene expression might play a unique role in the proliferation and/or differentiation of leukemic cells and could be associated with the particular abnormal hemostasis of some leukemias.

    Topics: Annexins; Blotting, Northern; Bryostatins; Cell Differentiation; Cholecalciferol; Dactinomycin; Gene Expression Regulation, Neoplastic; Half-Life; Humans; Lactones; Leukemia; Leukemia, Myeloid; Leukemia, Promyelocytic, Acute; Lymphoma; Macrolides; RNA, Messenger; Tetradecanoylphorbol Acetate; Tretinoin; Tumor Cells, Cultured

1993
The acute promyelocytic leukemia-specific PML-RAR alpha fusion protein inhibits differentiation and promotes survival of myeloid precursor cells.
    Cell, 1993, Aug-13, Volume: 74, Issue:3

    Acute promyelocytic leukemia is a clonal expansion of hematopoietic precursors blocked at the promyelocytic stage. The differentiation block can be reversed by retinoic acid, which induces blast maturation both in vitro and in vivo. Acute promyelocytic leukemia is characterized by a 15;17 chromosome translocation with breakpoints within the retinoic acid alpha receptor (RAR alpha) gene on 17 and the PML gene, which encodes a putative transcription factor, on 15. A PML-RAR alpha fusion protein is formed as a consequence of the translocation. We expressed the PML-RAR alpha protein in U937 myeloid precursor cells and showed that they lost the capacity to differentiate under the action of different stimuli (vitamin D3 and transforming growth factor beta 1), acquired enhanced sensitivity to retinoic acid, and exhibited a higher growth rate consequent to diminished apoptotic cell death. These results provide evidence of biological activity of PML-RAR alpha and recapitulate critical features of the promyelocytic leukemia phenotype.

    Topics: Animals; Apoptosis; Carrier Proteins; Cell Cycle; Cell Differentiation; Cell Division; Cell Line; Cell Survival; Cholecalciferol; Chromosomes, Human, Pair 15; Chromosomes, Human, Pair 17; Cloning, Molecular; Humans; Kinetics; Leukemia, Promyelocytic, Acute; Mice; Plasmids; Polymerase Chain Reaction; Receptors, Retinoic Acid; Recombinant Fusion Proteins; Transcription Factors; Transfection; Transforming Growth Factor beta; Translocation, Genetic; Tretinoin; Tumor Cells, Cultured

1993
Interaction of retinoic acid and vitamin D3 analogs on HL-60 myeloid leukemic cells.
    Leukemia research, 1993, Volume: 17, Issue:9

    Retinoic acid (RA) is an interesting agent which has been shown to induce differentiation and complete remission in patients with acute promyelocytic leukemia. 1,25-(OH)2-delta 16-23-yne-cholecalciferol (16-23-D3) and 1,25-(OH)2-23-yne-cholecalciferol (23-D3) are vitamin D3 analogs capable of inducing differentiation of myeloid leukemic cells with little effect on either calcium absorption or mobilization. Using HL-60 myeloid leukemic cells as in vitro model for human acute myeloid leukemia we observed an additive to synergistic interaction between RA and 16-23-D3 or 23-D3 with respect to the inhibition of cell growth and DNA synthesis, the induction of differentiation and the loss of cell clonogenicity. In addition, we observed that RA and 16-23-D3 interact additively with respect to the reduction of c-myc mRNA expression. These results suggest that Ra used in combination with 16-23-D3 or 23-D3 may be an interesting chemotherapeutic regimen to evaluate in patients with acute myeloid leukemia.

    Topics: Cell Division; Cholecalciferol; Genes, myc; Humans; Leukemia, Promyelocytic, Acute; RNA, Messenger; RNA, Neoplasm; Tretinoin; Tumor Cells, Cultured

1993
Induction of the fms proto-oncogene product in HL-60 cells by vitamin D: a flow cytometric analysis.
    Leukemia research, 1992, Volume: 16, Issue:4

    Agents which induce monocytic characteristics in HL-60 human acute promyelocytic leukemia cells induce mRNA for the fms proto-oncogene, which encodes the receptor for M-CSF. Previous studies of fms expression in HL-60 cells have characterized chiefly induction by phorbol esters of fms mRNA. Our studies of fms expression in HI-60 cells have characterized induction by vitamin D3 of the fms protein. We have used flow cytometry to correlate fms antigen with a monocyte-specific differentiation antigen recognized by antibody MO2 (CD14), with DNA content, and with the nuclear antigen Ki-67, a marker of cell cycling. HL-60 cells were cultured with or without 1 microM vitamin D for 7 days. fms antigen was found on 42 +/- 5.8% of the cells cultured without vitamin D, but on 63 +/- 4.3% of the cells cultured with vitamin D. MO2 binding was detected on only 2 +/- 0.5% of the cells without vitamin D, but on 59 +/- 9% with vitamin D. Cells cultured with vitamin D that were fms-positive were also predominantly (83%) MO2-positive. Analysis of DNA content, measured by propidium iodide staining, showed that 57 +/- 1.5% of cells cultured without vitamin D, but 93 +/- 0.5% of cells cultured with vitamin D, were in the G0/G1 cell cycle phase. Analysis of nuclear antigen Ki-67 revealed that, of the vitamin D-treated cells that were fms-positive, a significant proportion (37%) were still cycling. We conclude that (1) fms is demonstrable on some uninduced HL-60 cells, (2) when HL-60 cells are induced to develop monocytic characteristics by vitamin D, fms induction is part of the program for monocytic differentiation that includes MO2 expression, yet (3) some induced cells expressing fms are still cycling.

    Topics: Antigens, Differentiation; Cell Cycle; Cholecalciferol; DNA, Neoplasm; Flow Cytometry; Gene Expression Regulation, Leukemic; Genes, fms; Humans; Ki-67 Antigen; Leukemia, Promyelocytic, Acute; Nuclear Proteins; Oncogene Protein gp140(v-fms); Proto-Oncogene Mas; Tumor Cells, Cultured

1992
Multiple mechanisms of regulation of the human c-myb gene during myelomonocytic differentiation.
    Oncogene, 1992, Volume: 7, Issue:9

    Alterations in expression of c-myb can have profound effects on the growth and differentiation of hematopoietic cells. Thus, it is important to understand the mechanisms by which c-myb is regulated during hematopoietic cell differentiation. Previous studies pertaining to the regulation of c-myb have been carried out with the avian and murine forms of the gene; the current studies were designed to determine the mechanisms of regulation of the human form of c-myb. Transcriptional analysis by nuclear run-on assays revealed that an attenuation of transcription was the means of primary regulation during retinoic acid- and vitamin D3-induced differentiation of HL-60 cells, while other mechanisms in addition to attenuation were active during dimethyl sulfoxide (DMSO)- and phorbol ester-induced differentiation. Densitometric analysis of the changes in c-myb transcription caused by phorbol ester suggested that the c-myb promoter may be down-regulated during phorbol ester-induced differentiation of HL-60. Additional studies exhibited post-transcriptional regulation by phorbol ester. DMSO was also shown to regulate c-myb at the post-transcriptional level. Interestingly, the post-transcriptional regulation of c-myb by DMSO required continuous transcription. This requirement was shared for c-myc but not ornithine decarboxylase expression. The transcriptional dependency of c-myb post-transcriptional regulation did not equate to translational dependency, thus a novel post-transcriptional regulatory mechanism may control c-myb gene expression. The multiple levels of regulation of c-myb suggest the importance of proper control for hematopoietic cell differentiation.

    Topics: Cell Differentiation; Cholecalciferol; Dimethyl Sulfoxide; Gene Expression Regulation, Neoplastic; Hematopoietic Stem Cells; Humans; Leukemia, Promyelocytic, Acute; Phorbol 12,13-Dibutyrate; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-myb; Proto-Oncogenes; RNA, Messenger; Transcription, Genetic; Tretinoin; Tumor Cells, Cultured

1992
Effects of protein kinase A and calcium/phospholipid-dependent kinase modulators in the process of HL-60 cell differentiation: their opposite effects between HL-60 cell and K-562 cell differentiation.
    Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research, 1991, Volume: 2, Issue:9

    We have previously shown that HL-60 cells treated with 1 alpha, 25-(OH)2D3 in magnesium-deficient medium are committed to differentiate but do not express differentiation-related phenotypes. In the present study, we demonstrated that Mg2+ deprivation blocked the process of differentiation before the induction of lysozyme mRNA and that the process of HL-60 cell differentiation could be divided into two steps, i.e., a commitment step and a phenotypic expression step. We studied the effects of protein kinase A (PKA) and calcium/phospholipid-dependent protein kinase (PKC) modulators at each step. The results indicated that agonists of PKA enhanced both steps but that N-(2-[methylamino]ethyl-5-isoquinolinesulfonamide inhibited them. On the other hand, 1-oleyl-2-acetylglycerol and 12-O-tetradecanoylphorbol-13-acetate enhanced the commitment step but inhibited that of phenotypic expression. Staurosporine and 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine inhibited the commitment step and enhanced that of phenotypic expression. These results indicate that PKA acts as a positive regulatory signal and that PKC has a dual role in the process of HL-60 cell differentiation, i.e., as a positive regulatory signal in the commitment step and as a negative one in the phenotypic expression step. Recently, we have also shown that in K-562 cell differentiation into erythroid lineage, PKA may serve as a negative regulatory signal in both steps; however, PKC may act dually, namely as a negative regulatory signal in the commitment step and as a positive one in the phenotypic expression step.(ABSTRACT TRUNCATED AT 250 WORDS)

    Topics: Alkaloids; Calcium; Cell Differentiation; Cell Line; Cholecalciferol; Diglycerides; Enzyme Activation; Gene Expression Regulation; Isoquinolines; Leukemia, Promyelocytic, Acute; Magnesium; Muramidase; Phenotype; Protein Kinase C; Protein Kinase Inhibitors; Protein Kinases; RNA, Messenger; Staurosporine; Tetradecanoylphorbol Acetate

1991
Lineage directed HL-60 cell sublines as a model system for the study of early events in lineage determination of myeloid cells.
    Leukemia research, 1990, Volume: 14, Issue:11-12

    Current experimental models are poorly suited to study the early biochemical and molecular events of the lineage determination process in myeloid progenitor cells. Viable lineage-committed precursors cannot be identified until after they have expressed their mature phenotype and these precursors cannot be grown to large number while lineage is committed but still immature. Recently, we have identified stable sublines of the HL-60 human leukemia cell line which differ from each other in that they selectively differentiate to either neutrophils (UR-1-4), monocyte/macrophages (MRI), eosinophils (clones 2 and 15), or mixtures of two (clones 7 and 8) or of all three lineages (UR-1-2) when stimulated to mature with butyric acid under identical conditions. Characterization of these sublines provided evidence that the expression of lineage in HL-60 cells is a multistep process and that the lineage tendencies (lineage direction) the clones exhibited when cultured with butyric acid represent a step in that process earlier than irreversible lineage commitment but later than the multipotential wild type HL-60 cells. First, treatment of these sublines with compounds that induce differentiation of HL-60 cells to specific lineages (dimethylsulfoxide, neutrophil; 1,25-(OH)2 vitamin D3, monocyte), generally induced differentiation to the lineage associated with that inducer rather than the butyrate-associated lineage. Second, culture of neutrophil or monocyte-directed sublines in medium of elevated pH for two months leads to the development of eosinophils. Culturing the sublines first in butyric acid for variable lengths of time and switching to either DMSO or VD3 indicated that irreversible lineage commitment develops on a time course similar to the development of the commitment to mature. Markers of monocytic and eosinophilic differentiation could not be simultaneously demonstrated in single mature cells, consistent with the phenomenon of lineage fidelity. In addition, several assays were validated that could reliably classify mature HL-60 cells to their lineage. The collection of these sublines appears to constitute a model system with well-defined behavior with respect to the early events of lineage determination that can be grown to quantities sufficient for biochemical and molecular analysis. Exploring the differences between these clones may provide a new way to examine the early events of the lineage development process in myeloid cells.

    Topics: Butyrates; Butyric Acid; Cell Differentiation; Cholecalciferol; Dimethyl Sulfoxide; Eosinophils; Hematopoietic Stem Cells; Humans; Leukemia, Promyelocytic, Acute; Models, Biological; Monocytes; Neutrophils; Tumor Cells, Cultured

1990
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