Azacitidine ; analogs & derivatives ; therapeutic use ; Humans ; Myelodysplastic Syndromes ; drug therapy

Myelodysplastic syndrome (MDS) is a clonal marrow stem cell disorder, characterized by ineffective haemopoiesis leading to blood cytopenias. As a disease of grey zone, along with the development of research, the exploration on its pathogenesis have been shifted from molecular genetics and the feature of immunophenotype to the epigenetic and micro environment. But at present, the pathogenesis of MDS is still not clear, the research of the molecular genetics and immunophenotype can not meet the needs of experimental and clinical application any longer. The hematopoietic stem cells, cytokines, epigenetic studies, however, have made a lot of achievements. Targeted medicine such as azacitidine and decitabine had promising response in treating MDS patients. In this article the abnormality of stromal cells, cytokines and epigenetic changes in hematopoietic microenvironment of MDS are reviewed in order to optimize the monitoring MDS progress and guide its clinical medication strategy.
Azacitidine ; analogs & derivatives ; Bone Marrow ; Cytokines ; Hematopoietic Stem Cells ; Humans ; Immunophenotyping ; Myelodysplastic Syndromes ; Stromal Cells

OBJECTIVETo investigate the effect of all transretinoicacid(ATRA) combined with decitabine (5-Aza-2'-deoxycytidine;DAC) on DNA methylation and gene expression of p16INK4a (p16) and retinoic acid receptor β (RARβ), and to explore their combined anti neoplastic effect on U937 cells and newly diagnose delder acute myeloid leukemia(AML) patients.

METHODSThe expression levels of p16 and RARβ were determined by qRT-PCR and Western blot. Methylation-specific PCR was used to analyze their methylation status. WST-1 and flow cytometry were performed to detect growth inhibition, differentiation, apoptosis and cell cycle of U937 cells respectively.

RESULTSThe expression p16 and RARβ was down-regulated by promoter hypermethylation in newly diagnose delder AML patients and U937 cells. Combination treatment of ATRA and DAC induced DNA hypomethylation as well as gene expression of p16 and RARβ, which contributed to the growth inhibition, differentiation, apoptosis and cell cycle arrest of U937 cells. In addition for elder AML patients intolerable to standard chemotherapy, the combination regimen of ATRA and DAC showed antineoplastic activity accompamied by up-regulation of p16 and RARβ expression and decrease of bone marrow blast, moreover the parients showed good tolerence to the reginen.

CONCLUSIONThe regimen of ATRA combined with DAC as the combination therapeutic strategy for inducing differentiation and demethylation possesses the anti-AML potency, and contributes to optimizing the therapeutic strategy for elder AML patients and promoting the clinical prognosis.

Azacitidine ; analogs & derivatives ; Decitabine ; Humans ; Leukemia, Myeloid, Acute ; Tretinoin ; U937 Cells

Aged ; Antimetabolites, Antineoplastic ; therapeutic use ; Azacitidine ; analogs & derivatives ; therapeutic use ; Female ; Humans ; Leukemia, Myelomonocytic, Chronic ; drug therapy

Findings in epigenetic changes in meylodysplastic syndromes (MDS) and the development of demethylating drugs provide a new approach to the treatment of MDS. We used standard-dose decitabine for treatment of MDS in an elderly patient with an International Prostate Symptom Score (IPSS) of moderate risk group 2, and achieved a complete response in the first course. We report our experience with this case and review the relevant literatures.
Azacitidine ; analogs & derivatives ; therapeutic use ; DNA Modification Methylases ; antagonists & inhibitors ; Female ; Humans ; Middle Aged ; Myelodysplastic Syndromes ; drug therapy

OBJECTIVETo evaluate the efficacy of decitabine (DAC) bridging therapy followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with myelodysplastic syndrome (MDS).

METHODSThe clinical characteristics and curative effect of MDS patients who received allo-HSCT from 2010 July to 2013 December were retrospectively analyzed. Of them, 25 MDS patients who received decitabine bridging allo-HSCT were randomly selected (referred to as the bridging group),while at the same time another 33 MDS patients who did not receive decitabine for allo-HSCT in MDS were also randomly selected as control group. The effect of decitabine bridging allo-HSCT on the patients' survival and occurrence of graft versus host disease (GVHD) was analyzed.

RESULTSWith decitabine bridge therapy, 64.0% patients (16/25) achieved marrow complete remission before allo-HSCT, while the control group was only 15.1% (5/33, P<0.05). Decitabine bridging group of early transplant-related mortality was lower than that of the control group (4.0% vs 18.2%), but the difference was not statistically significant (P=0.106). Up to follow-up deadline, the mortality of decitabine bridging group was 12.0%, while that of the control group was 30.3% (P<0.05). The 2-year OS of decitabine bridging group was 83.0%, while that of the control group was 59.0% (P<0.05). Of the 14 patients in decitabine bridging group with aGVHD, 7 was grade IaGVHD, 3 grade II and 4 grade III. Of the 16 patients in control group with aGVHD, 7 was grade IaGVHD, 8 grade II and 1 grade III.

CONCLUSIONDecitabine bridging therapy followed by allo-HSCT in the treatment of MDS is safe and effective.

Azacitidine ; analogs & derivatives ; Graft vs Host Disease ; Hematopoietic Stem Cell Transplantation ; Humans ; Myelodysplastic Syndromes ; Retrospective Studies ; Transplantation, Homologous

Azacitidine ; analogs & derivatives ; therapeutic use ; Clinical Trials, Phase III as Topic ; Humans ; Leukemia, Myeloid, Acute ; drug therapy ; Multicenter Studies as Topic

OBJECTIVETo investigate the reversal effects of different concentrations of DNA methylation inhibitor, 5-aza-2-deoxycytidine, on the hypermethylation of maternally expressed gene 3 (MEG3) gene promoter, and then the inhibitory effect of restoration of MEG3 expression on the proliferation of ovarian cancer cells.

METHODSHuman ovarian cancer OVCAR3 cells were treated with various concentration of 5-aza-2-deoxycytidine (0, 1, 5, 10, 20 µmol/L, respectively) for 6 days. Then the methylation status of MEG3 promoter was detected by methylation specific PCR (MSP). The alteration of MEG3 gene expression was detected by RT-PCR. Cell proliferation was determined by MTT assay and EdU incorporation assay.

RESULTSAfter treated with 5-aza-2-deoxycytidine, the methylation status of MEG3 in the 0, 1, 5, 10, 20 µmol/L 5-aza-2-deoxycytidine groups were 1.00 ± 0.00, 0.79 ± 0.00, 0.67 ± 0.00, 0.65 ± 0.03 and 0.61 ± 0.01 folds, respectively (P < 0.05 for all). The relative expressions of MEG3 mRNA in the 0, 1, 5, 10, 20 µmol/L 5-aza-2-deoxycytidine groups were 1.00 ± 0.00, 2.04 ± 0.16, 2.44 ± 0.17, 3.19 ± 0.34 and 5.34 ± 0.39, respectively (P < 0.05 for all). In contrast to the negative control, the inhibition rates of the OVCAR3 cell growth were increased significantly when treated with 1, 5, 10, 20 µmol/L 5-aza-2-deoxycytidine in 2, 4 and 6 days. There were (40.78 ± 0.80)%, (35.65 ± 0.33)%, (31.81 ± 0.66)%, (27.33 ± 1.27)% and (17.75 ± 1.85)% of EdU-positive cells in the 0, 1, 5, 10 and 20 µmol/L 5-aza-2-deoxycytidine groups (P < 0.01 for all).

CONCLUSIONSMaternally expressed gene 3 promoter hypermethylation is reversed by 5-aza-2-deoxycytidine in ovarian cancer cells. The downregulation of MEG3 gene might be resulted from the methylation, and the re-expression of MEG3 partly contribute to the growth inhibition of epithelial ovarian cancer cells.

Antimetabolites, Antineoplastic ; pharmacology ; Azacitidine ; analogs & derivatives ; pharmacology ; Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; DNA Methylation ; Female ; Humans ; Neoplasms, Glandular and Epithelial ; Ovarian Neoplasms ; Promoter Regions, Genetic ; RNA, Messenger

This study was aimed to investigate the effect of 5-Aza-CdR on the biological activity of human erythroleukemia cell line K562 and the expression of inhibitor of DNA binding 4 (ID4). ID4 methylation in K562 cell line was detected by methylation-specific PCR. RQ-PCR was used to analyze the expression levels of ID4 mRNA in K562 cell line treated by different concentrations of 5-Aza-CdR. Cell apoptosis rate and cell cycle were analyzed by flow cytometry. The result showed that ID4 gene methylation existed in K562 cells, ID4 mRNA expression in K562 cells treated with 5-Aza-CdR increased in a concentration-dependent manner, the difference between experimental groups was statistical significant (p < 0.01). The 5-Aza-CdR could enhance the apoptotic rate of K562 cells in time and dose-dependent manner, the apoptotic rate of K562 cells highly correlated to relative expression level of ID4 mRNA (r = 0.95). After the K562 cells were treated by 5-Aza-CdR for 48 hours, cells in G(0)/G(1) phase increased, cells in G(2)/M phase decreased along with enhancement of drug concentration. It is concluded that methyltransferase inhibitor 5-Aza-CdR can re-express the silent ID4 gene in K562 cells. The upregulation of ID4 may be a key factor to give rise to cell apoptosis, and the cell cycle of K562 cells can be arrested by 5-Aza-CdR.
Apoptosis ; drug effects ; Azacitidine ; analogs & derivatives ; pharmacology ; Cell Cycle ; Cell Proliferation ; drug effects ; DNA Methylation ; Gene Expression ; drug effects ; Humans ; Inhibitor of Differentiation Proteins ; genetics ; K562 Cells

This study was aimed to investigate the methylation status of WT1 gene in leukemia cell lines and its relation with expression of WT1 gene. The WT1 gene was silenced by DNA methylation or histone deacetylation, and the expression of WT1 gene was induced by using HDAC inhibitor and/or demethylation agent of DNA. Some leukemia cell lines (U937, HL-60, K562, KG1) were detected by RT-PCR, MS-PCR, restriction analysis, and DNA sequencing. U937 leukemic cells without WT1 mRNA expression were incubated with HDAC inhibitor Trichostatin A (TSA) and/or demethylation agent decitabine. The results showed that the U937 cells did not express WT1 gene, but HL-60, K562 and KG1 cells highly expressed WT1 gene; WT1 gene was unmethylated in HL-60 cells, but methylated in K562 and U937 cells. WT1 expression could be reactivated by co-incubation with TSA and decitabine, but not was observed by using single drug. It is concluded that WT1 promoter is methylated in some leukemia cells, however, the methylation can not affect its expression. DNA methylation and deacetylation of histones are synergistic to inhibit the expression of WT1 in leukemic U937 cells, the combination of TSA with decitabine can induce expression of WT1 gene.
Azacitidine ; analogs & derivatives ; pharmacology ; DNA Methylation ; Gene Silencing ; HL-60 Cells ; Histones ; metabolism ; Humans ; Hydroxamic Acids ; pharmacology ; K562 Cells ; Promoter Regions, Genetic ; U937 Cells ; WT1 Proteins ; genetics