Epigenesis, Genetic ; Humans ; Myelodysplastic Syndromes ; drug therapy ; genetics

The effects of conventional treatment for myelodysplastic syndrome (MDS) are not remarkable to date, while only a minority of patients was eligible for allogeneic stem cell transplantation. As epigenetics plays a significant role during the occurrence and development of MDS, and histone deacetylase inhibitors (HDACI), a class of gene expression modulating drugs, are currently being developed for therapy of several types of solid tumor, more attention is paying to HDACI as potential therapy of MDS. This review summarizes briefly the rationale for HDACI use in MDS, the common mechanism of HDACI, the present state of the clinical efficiency, and future development in this field.
Epigenesis, Genetic ; Histone Deacetylase Inhibitors ; therapeutic use ; Humans ; Myelodysplastic Syndromes ; drug therapy ; genetics

OBJECTIVETo detect p15(INK4B) methylation levels and the kinetics of the methylation status before and after decitabine to explore its influences on prognosis and response to decitabine in myelodysplastic syndromes (MDS) patients.

METHODSWe examined 261 MDS patients (143 male and 118 female) with the median age of 52 years (32-78). Of them, 172 cases were low-risk group (low-risk 104 cases, intermediate-1 68 cases), 89 cases high-risk group (intermediate-2 52 cases, high risk 37 cases). Collections of bone marrow mononuclear cells of MDS patients and extracted the genomic DNA, the methylation status of p15(INK4B) was detected by methylation-specific PCR (MSP) method. Survival analysis was conducted according to the level of p15(INK4B) methylation in the cohort of patients. The kinetics of the methylation levels of p15(INK4B) in 58 MDS patients before and after 2 courses of decitabine have been assessed with the method of MSP.

RESULTSThe methylation level of p15(INK4B) in low-risk group patients was significantly lower than that in high-risk group (117.22 vs 157.63, P<0.05 ). The expected 2-year survival rate of p15(INK4B) methylation positive patients was lower than that of negative ones (91.8% vs 69.8%, P<0.05); the expected 2-year survival rate of p15(INK4B) methylation positive patients was shorter than that of negative ones in low-risk group（78.2% vs 92.0%, P<0.05）, meanwhile there was no significant difference in terms of expected 2-year survival rate and median expected survival between p15(INK4B) methylation positive and negative patients in high-risk group [35.6% vs 38.5%, (17.0±9.3) month vs (18.0±5.7) month, P>0.05]. Multivariate analysis showed p15(INK4B) methylation degree was an independent prognostic factor for overall survival. No statistical difference of overall response (OR) rates were found between p15(INK4B) methylation positive patients and negative patients before decitabine（65.9% vs 76.5%, P>0.05）, and complete remission (CR) rates between these two groups also showed no statistical difference（22.0% vs 29.4%, P>0.05）. p15(INK4B) methylation levels had no obvious change before and after treatment in decitabine responders（P>0.05）.

CONCLUSIONThe survival of newly diagnosed MDS patients with positive p15(INK4B) methylation was comparatively shorter, but p15(INK4B) methylation had no influence on response to decitabine.

Adult ; Aged ; Azacitidine ; analogs & derivatives ; Cyclin-Dependent Kinase Inhibitor p15 ; genetics ; DNA Methylation ; Female ; Humans ; Male ; Middle Aged ; Myelodysplastic Syndromes ; drug therapy ; genetics ; Prognosis ; Survival Rate ; Treatment Outcome

The objective was to study the incidence and prognosis significance of -7/7q- abnormalities in acute leukemia and myelodysplastic syndrome. Conventional cytogenetic analysis of R-band was used to test -7/7q- chromosome abnormalities in 410 patients with acute leukemia (AL), in 71 cases of myelodysplastic syndrome (MDS) and in 36 cases of chronic myelogenous leukemia in accelerated phase (CML-AP). The results showed that the incidences of -7/7q- abnormalities in AL, MDS and CML-AP patients were 4.88%, 9.86% and 8.33% respectively. The -7/7q- abnormalities could be found in acute myeloblastic leukemia (AML) and acute lymphocytic leukemia (ALL), incidences of which were 4.70% and 6.25% (P > 0.05) respectively. 9 cases had -7 or 7q- as the sole chromosome abnormalities, 22 cases showed other additional chromosome abnormalities: -X, -5, +8, t(3; 3), t(11;16) and t(2;11). Monosomy -7 and 7q- abnormality clone was found in one patient with MDS-RAEB, and the number of cells with -7 abnormality was greater than that of 7q- abnormality cells. Four patients acquired CR among 7 patients with ALL after chemotherapy, but 2 out of 13 patients with AML achieved CR while 6 out of 7 patients with MDS transformed into AL. No patients with CML-AP achieved CR. In conclusion, -7/7q- is a frequent aberration in hematologic malignancies as well as AML and ALL. The monosomy -7 and 7q-abnormalities were detected in the same patient. The patients with -7/7q- abnormalities show poor prognosis.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Chromosome Aberrations ; Chromosomes, Human, Pair 7 ; Female ; Humans ; Leukemia, Myeloid, Acute ; drug therapy ; genetics ; mortality ; Male ; Middle Aged ; Myelodysplastic Syndromes ; drug therapy ; genetics ; mortality ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; genetics ; mortality

Adult ; Aged ; Chromosomes, Human, Pair 8 ; Cyclosporine ; therapeutic use ; Female ; Humans ; Karyotyping ; Male ; Middle Aged ; Myelodysplastic Syndromes ; drug therapy ; genetics ; Retrospective Studies ; Trisomy ; Young Adult

Adult ; Antimetabolites, Antineoplastic ; administration & dosage ; therapeutic use ; Azacitidine ; administration & dosage ; analogs & derivatives ; therapeutic use ; Female ; Humans ; Karyotype ; Leukemia, Myeloid, Acute ; drug therapy ; genetics ; Male ; Middle Aged ; Myelodysplastic Syndromes ; drug therapy ; genetics ; Treatment Outcome

To investigate the effect of 5-aza-2'-deoxycytidine (5-Aza-CdR) on cell of high-risk patients with myelodysplastic syndrome (MDS) in vitro, the growth inhibition of MUTZ-1 cell induced by 5-Aza-CdR was detected by MTT method; apoptosis was detected by morphological observation and translocation of phosphatidylserine (PS) was examined by flow cytometry assay; the expressions of P15INK4B, DNA methyltransferases (DNMT)(1), DNMT(3A) and DNMT(3B) gene on mRNA level were detected by RT-PCR; methylation of p15INK4B gene in MUTZ-1 cells was detected by PCR using methylation specific primer (MSP). The results showed that 5-Aza-CdR inhibited the growth of MUTZ-1 cells. The IC(50) values of 24, 48 and 72 hours were 6.75, 2.82 and 5.45 mmol/L respectively. Characteristic changes of apoptosis emerged in MUTZ-1 cells after being exposed to 5-Aza-CdR in the different concentration from 0.8 mmol/L to 3.2 mmol/L, and the positive cells of annexin V on the membrane of MUTZ-1 cells were analyzed by flow cytometry. 5-Aza-CdR could activate the p15INK4B gene expression in MUTZ-1 cells by demethylation of the p15INK4B gene in a dose-dependent manner after the cells were treated for 48 hours. Furthermore, 5-Aza-CdR could significantly down-regulate the expressions of DNA methyltransferase genes DNMT(3A) at mRNA level in a dose dependent manner. However, it had no effects on DNMT(1) gene and DNMT(3B) gene. It is concluded that 5-Aza-CdR can inhibit the growth of MUTZ-1 cells and induce the apoptosis of these cells within the range of concentration from 0.8 mmol/L to 3.2 mmol/L, which may be one of the mechanisms of antitumor effects of 5-Aza-CdR. The drug can activate the expression of p15INK4B gene in MUTZ-1 cells by demethylation of the p15INK4B gene through inhibiting the expression of DNMT(3A) gene. It may be the mechanism of 5-Aza-CdR in the treatments of MDS.
Azacitidine ; analogs & derivatives ; pharmacology ; Cell Cycle Proteins ; genetics ; Cell Line ; Cell Proliferation ; drug effects ; Cyclin-Dependent Kinase Inhibitor p15 ; DNA Methylation ; DNA Modification Methylases ; metabolism ; Humans ; Myelodysplastic Syndromes ; drug therapy ; pathology ; RNA, Messenger ; analysis ; Tumor Suppressor Proteins ; genetics

This study was aimed to detect the methylation status of FHIT gene promoter region in the DNA from plasma of patients with myelodysplastic syndrome (MDS), and to investigate the demethylating effect of decitabine. Methylation-specific PCR method was used to detect the methylation status of FHIT gene promoter region in the DNA from plasma of 4 patients with MDS before and after treatment with decitabine plus semis CAG therapy (among them, 1 case of newly diagnosed MDS, 3 cases progressed into acute leukemia). The results indicated that 3 cases were found to have an increased methylation in the promoter region. After treatment with decitabine plus semis CAG, increased methylation was reversed in 2 cases. In 4 cases, 2 cases displayed clinical response. It is concluded that FHIT gene hypermethylation is associated with MDS pathogenesis. Decitabine has demethylating effect on the FHIT gene hypermethylation of plasma from MDS patients. Detecting the methylation status of FHIT gene in DNA from plasma may play a role in MDS auxiliary diagnosis or prognosis.
Acid Anhydride Hydrolases ; genetics ; Adult ; Aged ; Azacitidine ; analogs & derivatives ; therapeutic use ; DNA ; blood ; DNA Methylation ; Female ; Humans ; Male ; Middle Aged ; Myelodysplastic Syndromes ; blood ; drug therapy ; Neoplasm Proteins ; genetics ; Promoter Regions, Genetic

OBJECTIVETo investigate the effect of topotecan (TPT) on human myelodysplastic syndrome (MDS) cells in vitro and in vivo.

METHODSCell growth was measured by a MTT assay. The percentage of cells undergoing apoptosis was determined by flow cytometry after staining with annexin V-FITC and propidium iodide. The morphology of apoptotic cells was observed by transmission electron microscopy (TEM). Furthermore, the antitumor effect on MDS cells in xenotransplanted severe combined immunodeficiency (SCID) mice was evaluated by tumor volume and survival. Western blot was used for determining the expression of topoisomerase I (Top1) protein.

RESULTThe growth of Mutz-1 cells was suppressed by TPT treatment in a dose-dependent manner. The 50% inhibition in Mutz-1 cell growth (IC(50)) of TPT for 72 h was 272 ng/L. The percentage of apoptotic cells observed in the Mutz-1 cells after exposure to TPT (160 ng/L) in 48 h and 72 h was (54.16 +/-4.29)% and (72.97+/-6.12)%, respectively. TEM showed the characteristics of apoptosis in Mutz-1 cells treated with TPT. The xenotransplanted SCID mice treated with TPT showed inhibited tumor growth compared with control group. TPT treatment resulted in a longer survival as compared with the control group (P<0.001) and with the As2O3-treated group (P<0.001). The cells exposed to TPT exhibited a time-dependent decrease of Top1 protein expression.

CONCLUSIONTPT can inhibit Mutz-1 cell growth and induce apoptosis in vitro.The downregulation of Top1 may be involved in the apoptosis induced by TPT. TPT has a significant antitumor effect in vivo.

Animals ; Antineoplastic Agents ; pharmacology ; therapeutic use ; Apoptosis ; drug effects ; DNA Topoisomerases, Type I ; biosynthesis ; genetics ; Down-Regulation ; Humans ; Mice ; Mice, SCID ; Myelodysplastic Syndromes ; drug therapy ; pathology ; Neoplasm Transplantation ; Topotecan ; pharmacology ; therapeutic use ; Tumor Cells, Cultured

DNA methyltransferase inhibitor, 5-azacitidine (AC) is effective in myelodysplastic syndromes (MDS) and can induce re-expression in cancer. We analyzed the methylation of 25 tumor suppressor genes in AC-treated MDS. Hypermethylation of CDKN2B, FHIT, ESR1, and IGSF4 gene was detected in 9/44 patients. In concordance with the clinical response, a lack of or decreased methylation in 4 patients with hematologic improvements and persistent methylation in 4 others with no response was observed. The mRNA expression of CDKN2B, IGSF4, and ESR1 was significantly reduced in MDS. Our results suggest that methylation changes contribute to disease pathogenesis and may serve as marker to monitor the efficacy of treatments.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Azacitidine/*pharmacology/*therapeutic use ; DNA Methylation/*drug effects ; DNA Modification Methylases/antagonists & inhibitors/metabolism ; Enzyme Inhibitors/*pharmacology/*therapeutic use ; Female ; Genes, Tumor Suppressor ; Humans ; Male ; Middle Aged ; Myelodysplastic Syndromes/*drug therapy/*genetics ; Young Adult