5-Aza-2'-deoxycitydine induces demethylation and up-regulates transcription of p16INK4A gene in human gastric cancer cell lines.
- Author:
Jing-yuan FANG
1
;
Li YANG
;
Hong-yin ZHU
;
Ying-xuan CHEN
;
Juan LU
;
Rong LU
;
Zhong-hua CHENG
;
Shu-dong XIAO
Author Information
- Publication Type:Journal Article
- MeSH: Azacitidine; analogs & derivatives; pharmacology; Cell Line, Tumor; DNA Methylation; Enzyme Inhibitors; pharmacology; Flow Cytometry; Gene Expression; Genes, Tumor Suppressor; physiology; Genes, p16; physiology; Humans; Reverse Transcriptase Polymerase Chain Reaction; Stomach Neoplasms; genetics; Transcription, Genetic; Up-Regulation
- From: Chinese Medical Journal 2004;117(1):99-103
- CountryChina
- Language:English
-
Abstract:
BACKGROUNDTo investigate the effects of DNA methylation on the expression of tumor-associated genes and the cell cycle in human gastric cancer cells.
METHODSTwo gastric cancer cell lines (MKN-45 and HGC-27) were treated with DNA methyltransferase (DNMT) inhibitor, 5-aza-2'-deoxycytidine (5-aza-dC). The expressions of p16INK4A, p21WAF1, p53, p73, c-Ha-ras and c-myc genes mRNA were detected by using reverse transcription PCR (RT-PCR). DNA methylation status of p16INK4A gene promoter was assayed by bisulfite modification and sequencing. The cell cycle was analyzed by using flow cytometry (FCM).
RESULTS5-aza-dC induced the demethylation of p16INK4A gene promoter. The expression of p16INK4A mRNA was obviously up-regulated by treatment with 10 micro mol/L (MKN-45 cells) or 5 micro mol/L (HGC-27 cells) of 5-aza-dC for 24 hours. However, 5-aza-dC treatment failed to regulate the expressions of p21WAF1, p53, p73, c-Ha-ras and c-myc genes in MKN-45 and HGC-27 cells. Furthermore, 5-aza-dC induced the cell cycle arrest in G1 phase in HGC-27 cell, but not in MKN-45 cell.
CONCLUSIONSDNA methylation regulates the transcription of p16INK4A but not p21WAF1 and proto-oncogenes in human gastric cancer cell lines MKN-45 and HGC-27.
