广东医学2012，Vol.33Issue(16)：2367-2371,5.
启动子甲基化致OPCML基因失活在胃癌发病中的作用
Promoter methylation-induced OPCML expression silence in progression of gastric cancer
摘要
Abstract
Objective To assess the expression of OPCML ( opioid - binding protein/cell adhesion molecule like ) in gastric cancer cells, and its correlation with methylation of promoter CpG islands. Methods ( 1) The stomach cancer ceU lines, which included SGC7901, AGS, MKN28, MKN45, N87, KATO Ⅲ and SNU1, were cultured as experimental group whereas the normal stomach tissue as control. OPCML mRNA expression was assesses by RT-PCR. ( 2 ) The DNA extracted form normal stomach tissue and stomach cancer cells MKN45 was modified by sulfites for further analysis of OPCML gene promoter methylation with MSP ( Methylation specific PCR ). ( 3 ) MKN45 cells were demethylated by 5 - AZA ( 5' - aza - 2' - deoxycytidine ) for comparison with those without demethylation on OPCML mRNA expression by RT - PCR. ( 4 ) The OPCML mRNA expression was assessed by RT - PCR in stomach cancer cells transfected with OPCML expression vector or empty carrier. ( 5 ) AGS cells transfected with OPCML expression vector and empty carrier were screened with neomycin ( G418, 0. 5 mg/mL ). Results ( 1 ) OPCML expression in gastric cancer cells was aberrantly reduced in contrast to normal gastric tissue. ( 2 ) Significant up - regulation of methylation of OPCML gene promoter was observed in gastric cancer AGS and MKN45 cell lines comparing with that of normal gastric tissues. ( 3 ) OPCML expression was up-regulated as 5-AZA-indudced demethylation. ( 4 ) OPCML expression was up-regulated by transfection of OPCML expression vector in HEK293A, AGS and MKN45 cells. ( 5 ) Ectopic expression of OPCML in gastric cancer cells with endogenous silencing led to strong inhibition of cell colony formation. Conclusion The OPCML is a tumor suppressor gene and down - regulated in gastric cancer cells, which is induced by methylation of promoter CpG island. This process is restored with demethylation by 5-AZA. Ectopic expression of OPCML in gastric cancer cells with endogenous silencing leads to strong inhibition of cell colony formation.关键词
gastric cancer cells/ OPCML gene/ methylationKey words
gastric cancer cells/ OPCML gene/ methylation引用本文复制引用
张宁,许继德,元刚,陈洁,陈旻湖,邢象斌..启动子甲基化致OPCML基因失活在胃癌发病中的作用[J].广东医学,2012,33(16):2367-2371,5.基金项目
国家自然科学基金资助项目(编号:81000887),高等学校博士学科点专项科研基金资助项目(编号:20090171120064),广东省医学科研基金资助项目(编号:B2010077) （编号:81000887）
