Although the traditional chemotherapy has achieved a certain effect for patients with acute myeloid leukemia (AML), but there are still limitations in terms of improving the rate of complete remission and overcome relapse after remission. The further study found that many cytogenetic molecular and epigenetic abnormalities occurred during the progression of AML, such as abnormal expression of cell surface molecules, mutation, gene aberrant methylation and so on. The drugs targeted at these changes can improve the prognosis for patients, and provide a new way for treating patients with AML. At present, the mostly targeted drugs include monoclonal antibodies CD33-Ab, tyrosine kinase inhibitor, inhibitors of DNA methyltransferases inhibitors and so on. In this review, the progress of targeted therapy in AML treatment is summarized.
Antibodies, Monoclonal ; therapeutic use ; DNA Modification Methylases ; antagonists & inhibitors ; Humans ; Leukemia, Myeloid, Acute ; drug therapy ; Mutation ; Prognosis ; Protein Kinase Inhibitors ; therapeutic use ; Remission Induction

BACKGROUNDGene therapy and epigenetic therapy have gained more attention in cancer treatment. However, the effect of a combined treatment of gene therapy and epigenetic therapy on head and neck squamous cell carcinoma have not been studied yet. To study the mechanism and clinical application, human laryngeal carcinoma cell (Hep-2) tumor-bearing mice were used.

METHODSA xenograft tumor model was established by the subcutaneous inoculation of Hep-2 cells in the right armpit of BALB/c nu/nu mice. The mice with well-formed tumor were randomly divided into six groups. Multisite injections of rAd-p53 and/or 5-aza-dC were used to treat tumor. Tumor growth was monitored by measuring tumor volume and growth rate. p53 and E-cadherin protein levels in tumor tissues were detected by immunohistochemical staining. The mRNA levels were monitored with FQ-PCR.

RESULTSGene therapy was much more effective than single epigenetic therapy and combined therapy. The gene therapy group has the lowest tumor growth rate and the highest expression levels of p53 and E-cadherin.

CONCLUSIONSThe combined treatment of gene and epigenetic therapy is not suggested for treating head and neck carcinoma, because gene therapy shows an antagonistic effect to epigenetic therapy. However, the mechanisms of action are still unclear.

Animals ; Azacitidine ; analogs & derivatives ; therapeutic use ; Cadherins ; analysis ; DNA Modification Methylases ; antagonists & inhibitors ; Epigenesis, Genetic ; Genes, p53 ; Genetic Therapy ; Humans ; Laryngeal Neoplasms ; genetics ; pathology ; therapy ; Male ; Mice ; Mice, Inbred BALB C ; Tumor Suppressor Protein p53 ; analysis ; Xenograft Model Antitumor Assays

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 study the regulation of methylation inhibitor 5-aza-2'-deoxycytidine on transcription of EphB4 gene and effects on the proliferation and apoptosis of human acute lymphocyte leukemia cell line CEM.

METHODSBisulfite sequencing PCR was used to detect CpG island methylation density in EphB4 promoter. The expression of EphB4 mRNA and protein was determined by Q-PCR and Western blot. MTS assay and flow cytometry were used to detect the apoptosis of CEM cells after treatment with different concentrations of 5-aza-2'-deoxycytidine (1.0, 2.5 and 5 μmol/L).

RESULTSMethylation of EphB4 gene promoter was detected in CEM cells (31.4%). The methylation level of EphB4 gene was down-regulated after treatment with various concentrations of 5-aza-2'-deoxycytidine. The EphB4 mRNA and protein expression in CEM cells increased after 5-aza-2'-deoxycytidine treatment. 5-Aza-2'-deoxycytidine significantly inhibited the cell growth in dose and time dependent manners. Early apoptosis rates of CEM cells increased from 4.1% to 24.8% 96 hrs after 5-aza-2'-deoxycytidine treatment. CEM cells in G1 phase decreased from 62.4% to 46.8%, cells in G2 phase increased from 2.1% to 16.2%, and CEM cells were arrested in G2 phase after treatment with 5 μmol/L 5-aza-2'-deoxycytidine for 96 hrs.

CONCLUSIONS5-Aza-2'-deoxycytidine, an inhibitor of specific methylation transferase, can induce expression of the silent EphB4 gene in CEM cells, inhibit the proliferation of leukemia cells and induce cell apoptosis.

Apoptosis ; drug effects ; Azacitidine ; analogs & derivatives ; pharmacology ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; DNA Methylation ; DNA Modification Methylases ; antagonists & inhibitors ; Humans ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; pathology ; RNA, Messenger ; analysis ; Receptor, EphB4 ; genetics

OBJECTIVETo observe the expression of SFRP1 gene methylation in non-small cell lung cancer (NSCLC), and study the effect of 5-Aza-2-deoxycytidine (5-Aza-CdR) on DNA methylation and expression of SFRP1, p16 and MGMT genes in the human lung cancer cell line SPC-A-1 cells.

METHODSSP immunohistochemistry and methylation-specific PCR were used to detect the SFRP1 methylation in 60 NSCLC cases, and 21 cases of benign lung diseases were used as control group. SPC-A-1 cells were cultured and treated with 5-Aza-CdR. The promoter methylation status of SFRP1, p16 and MGMT genes were detected by methylation-specific polymerase (MSP) chain reaction, and mRNAs were detected by real-time PCR.

RESULTSThe positive rate of SFRP1 gene methylation in NSCLC was significantly higher than that in normal lung tissue (58.3% vs. 14.3%; χ(2) = 12.118, P = 0.001). SFRP1 gene methylation was closely correlated with lymph node metastasis and degree of differentiation in NSCLC (P < 0.05). SFRP1 protein expression was correlated with clinical stage, degree of differentiation and lymph node metastasis in NSCLC (P < 0.05). The positive expression of SFRP1 protein in 30 cases of NSCLC tissue containing SFRP1 gene methylation was significantly higher than that in non-methylated NSCLC (68.6% vs. 24.0%; χ(2) = 9.613, P = 0.002). SFRP1 gene methylation was closely correlated with SFRP1 gene protein expression in NSCLC (P < 0.05). Negative expression of SFRP1 protein was correlated with the differentiation, clinical stage, and lymph node metastasis in NSCLC (all P < 0.05). Without 5-Aza-CdR treatment, the expressions of methylation of SFRP1, p16 and MGMT genes and their mRNA were low. After 5-Aza-CdR treatment at different concentrations, their expressions were significantly elevated (all P < 0.05).

CONCLUSIONSSFRP1 gene methylation is closely associated with carcinogenesis and development of NSCLC. 5-Aza-CdR may reverse the methylation of SFRP1, p16 and MGMT genes, and facilitate the re-expression of the anti-oncogenes.

Antimetabolites, Antineoplastic ; pharmacology ; Azacitidine ; analogs & derivatives ; pharmacology ; Carcinoma, Non-Small-Cell Lung ; metabolism ; pathology ; Cell Differentiation ; Cell Line, Tumor ; Cyclin-Dependent Kinase Inhibitor p16 ; genetics ; metabolism ; DNA Methylation ; DNA Modification Methylases ; antagonists & inhibitors ; genetics ; metabolism ; DNA Repair Enzymes ; genetics ; metabolism ; Female ; Gene Expression Regulation, Neoplastic ; Humans ; Intercellular Signaling Peptides and Proteins ; genetics ; metabolism ; Lung Neoplasms ; metabolism ; pathology ; Lymphatic Metastasis ; Male ; Membrane Proteins ; genetics ; metabolism ; Neoplasm Staging ; RNA, Messenger ; metabolism ; Tumor Suppressor Proteins ; genetics ; metabolism

OBJECTIVE: To analyze the effect of DNA hypermethylation on NOR1 promoter activity and expression. METHODS: NOR1 promoter plasmids were treated with SssI methyltransferase. The plasmids were modified by sodium bisulfite and purified. Sodium bisulfite-modified plasmids were subjected to PCR with primers designed to analyze the methylation status of 26 CpG sites in a 311-bp region of the NOR1 promoter. Cells were transfected by methylated or mock-methylated promoter plasmids. The promoter activities were assessed by the luciferase levels of cell lysates or by directly observing GFP expression under fluorescence microscope. HL60 cells were treated with different concentrations of 5-aza-dC. Total RNA was isolated from harvested cells. Real-time RT-PCR was used to measure the expression level of NOR1 mRNA. RESULTS: Bisulfite sequencing confirmed that SssI methyltransferase treatment successfully resulted in intensive hypermethylation of the NOR1 promoter plasmids. The promoter activity of NOR1 promoter plasmids was totally blocked by SssI methyltransferase treatment. NOR1 expression levels in HL60 cells were restored by 5-aza-dC treatment. CONCLUSION NOR1 promoter plasmids are intensively hypermethylated by SssI methyltransferase treatment. The promoter activity of NOR1 promoter plasmids are totally blocked by SssI methyltransferase treatment. The 5-aza-dC treatment may restore the endogenous NOR1 mRNA level in HL60 cells.
Azacitidine ; analogs & derivatives ; pharmacology ; Base Sequence ; Cell Line, Tumor ; CpG Islands ; DNA Methylation ; DNA Modification Methylases ; antagonists & inhibitors ; DNA-Cytosine Methylases ; pharmacology ; Decitabine ; Epigenesis, Genetic ; Gene Silencing ; HL-60 Cells ; Humans ; Membrane Transport Proteins ; genetics ; metabolism ; Molecular Sequence Data ; Nasopharyngeal Neoplasms ; pathology ; Promoter Regions, Genetic ; genetics ; RNA, Messenger ; genetics ; metabolism

Epstein-Barr virus (EBV) microRNAs (miRNAs) are expressed in EBV-associated tumors and cell lines, but the regulation mechanism of their expression is unclear yet. We investigated whether the expression of EBV miRNAs is epigenetically regulated in EBV-infected B cell lines. The expression of BART miRNAs was inversely related with the methylation level of the BART promoter at both steady-state and following 5-aza-2'-deoxycytidine treatment of the cells. The expression of BHRF1 miRNAs also became detectable with the demethylation of Cp/Wp in latency I EBV-infected cell lines. Furthermore, in vitro methylation of the BART and Cp promoters reduced the promoter-driven transactivation. In contrast, tricostatin A had little effect on the expression of EBV miRNA expression as well as on the BART and Cp/Wp promoters. Our results suggest that promoter methylation, but not histone acetylation, plays a role in regulation of the EBV miRNA expression in EBV-infected B cell lines.
Azacitidine/analogs & derivatives/pharmacology ; B-Lymphocytes/metabolism/virology ; Cell Line ; *DNA Methylation ; DNA Modification Methylases/antagonists & inhibitors ; Gene Expression Regulation, Viral ; Gene Silencing ; Herpesvirus 4, Human/*genetics/physiology ; Humans ; MicroRNAs/genetics/*metabolism ; *Promoter Regions, Genetic ; RNA, Viral/genetics/*metabolism ; Viral Proteins/genetics

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

OBJECTIVETo compare the sensitivity of different hepatocellular carcinoma (HCC) cell lines (HepG2, QGY7701, HepG2.2.15) and the normal liver cell line L02 to 5-aza-dC, an DNA methyltransferase inhibitor, and to explore the relationship between global DNA methylation level and the sensitivity to 5-aza-dC.

METHODSHepG2, QGY7701, HepG2.2.15 and L02 cells were treated with 5-aza-dC at different concentration, cell proliferation was measured by MTT method, cell apoptosis was detected by measuring caspase 3 activity and cellular DNA fragmentation ELISA.

RESULTSCompared to HepG2 and QGY7701 cells, HepG2.2.15 were less sensitive to the treatment of 5-aza-dC; the normal liver cell line L02 was less sensitive to 5-aza-dC than the HCC cell lines.

CONCLUSIONSThe sensitivity to 5-aza-dC of HCC cell lines and normal liver cells is not correlated with the global DNA methylation level.

Azacitidine ; analogs & derivatives ; pharmacology ; Carcinoma, Hepatocellular ; metabolism ; Caspase 3 ; metabolism ; DNA Methylation ; drug effects ; DNA Modification Methylases ; antagonists & inhibitors ; Hep G2 Cells ; Humans

OBJECTIVETo investigate the effects of 5-Aza-deoxycytidine (5-Aza-CdR) on the amount of exosomes and immuno-associated proteins produced in hepatoma HepG2 and Hep3B cells.

METHODSExosomes derived from HepG2 and Hep3B cells with or without treatment by 5-Aza-CdR were isolated and purified by combination of ultrafiltration centrifugation and sucrose gradient ultracentrifugation. The number of exosomes was counted under the electron microscope. The concentration of proteins in exosomes was detected by BCA. The expression of HSP70, HLA-I and NY-ESO-1 proteins in exosomes was assayed by Western blot and immuno-electron microscopy. The mRNA expression of p53 gene was observed by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSThe mRNA expression of p53 gene was increased in both hepatoma cell lines after treatment with 5-Aza-CdR. The number of exosomes and the concentration of total proteins in exosomes were significantly increased after treatment by 5-Aza-CdR (P < 0.05). The immuno-electron microscopy and Western blotting showed that after treatment with 5-Aza-CdR, the contents of HSP70, HLA-I and NY-ESO-1 proteins were increased in exosomes in both HepG2 and Hep3B hepatoma cells.

CONCLUSION5-Aza-CdR, an inhibitor of DNA methyltransferase, can increase the amount of exosomes and exosome-containning immuno-associated proteins secreted by hepatoma cells. It may be contributed by up-regulation of p53 gene and demethylation mechanism of 5-Aza-CdR.

Antigens, Neoplasm ; metabolism ; Antimetabolites, Antineoplastic ; pharmacology ; Azacitidine ; analogs & derivatives ; pharmacology ; Carcinoma, Hepatocellular ; pathology ; secretion ; DNA Methylation ; DNA Modification Methylases ; antagonists & inhibitors ; Exosomes ; secretion ; Gene Expression Regulation, Neoplastic ; HSP70 Heat-Shock Proteins ; metabolism ; Hep G2 Cells ; Histocompatibility Antigens Class I ; metabolism ; Humans ; Liver Neoplasms ; pathology ; secretion ; Membrane Proteins ; metabolism ; RNA, Messenger ; metabolism ; Tumor Suppressor Protein p53 ; genetics ; metabolism ; Up-Regulation