5-氮杂-2'-脱氧胞苷对肺癌SPC-A-1细胞RAR-β基因去甲基化及其表达的作用  

Study of 5-Aza-CdR induced demethylation of RAR-β Gene and its expression in lung cancer cell line SPC-A-1

作　　者：李琪[1] 刘莉敏[1] 杨玉梅[1] 谢艳丽[1] 李玉磊[1] 

机构地区：[1]武汉科技大学附属天佑医院呼吸内科,武汉430064

出　　处：《广东医学》2016年第15期2234-2237,共4页Guangdong Medical Journal

基　　金：湖北省教育厅科学研究计划项目(编号:Q20131106)

摘　　要：目的观察5-氮杂-2'-脱氧胞苷(5-Aza-CdR)对肺腺癌SPC-A-1细胞视黄酸受体β(RAR-β)基因甲基化状态的影响,探讨不同浓度5-Aza-CdR对RAR-β基因表达缺陷的调控机制。方法将体外培养的人肺腺癌SPC-A-1细胞株分为4组,分别是A组(未加药)及B、C、D组(分别加入3、6、12μmol/L的5-Aza-CdR)。采用甲基化特异性PCR(MSP)方法检测4组细胞RAR-β基因甲基化状态的差异,RT-PCR法检测4组细胞RAR-βmRNA表达水平的差异,Western blot检测4组细胞RAR-β蛋白表达水平的差异,流式细胞仪技术检测各组细胞周期及细胞凋亡率的差异。结果 A组标本检测出RAR-β基因为甲基化状态,而B、C、D组均检测出RAR-β为去甲基化状态。肺腺癌SPC-A-1细胞RAR-βmRNA及RAR-β蛋白表达水平低下,经5-Aza-CdR处理后,其表达水平明显增强(P<0.01)。5-Aza-CdR处理后(B、C、D组)的细胞凋亡率均较A组明显提高,差异有统计学意义(P<0.01)。结论肺癌RAR-β基因因甲基化出现表达缺陷,5-Aza-CdR具有明显去甲基化作用,可诱导RAR-β基因重新激活表达,促进肺癌细胞凋亡及抑制癌细胞增殖,从而发挥抗癌作用。Objective To observe effects of 5- Aza- CdR on RAR- β gene methylation status changes in lung adenocarcinoma cells SPC- A- 1,and to investigate the regulatory mechanism of 5- Aza- CdR in different concentrations for defective expression of RAR- β gene. Methods The human lung adenocarcinoma SPC- A- 1 cells were divided into four groups： Group A（ control group） and Group B,C,D（ dosing groups）. Differences in RAR- β gene methylation status,mRNA expression and protein expression among the four groups were assessed by methylation- specific PCR（ MSP）,RT- PCR,and Western blot,respectively. Furthermore,differences in cell cycle and apoptosis rate among the four groups were detected by Flow cytometry. Results RAR- β gene methylation was observed in Group A,while demethylation of RAR- β gene was observed in the other 3 groups. After 5- Aza- CdR treatment,the expression levels of RAR- β in SPC- A- 1 cells were significantly enhanced（ P〈0. 01）. Apoptosis rates in 5- Aza- CdR treatment groups were significantly increased compared with Group A（ P〈0. 01）. Conclusion RAR- β gene in lung cancer is defective expressed due to its methylation,which could be reversed by 5- Aza- CdR via its demethylation effect. 5- Aza-CdR promotes apoptosis and inhibits cell proliferation in lung cancer,and thus plays a role in cancer treatment.

关 键 词：5-氮杂-2'-脱氧胞苷 RAR-β基因 去甲基化 肺肿瘤 

分 类 号：R734.2[医药卫生—肿瘤]