miRNA-335基因启动子区甲基化与胃癌细胞不良生物学行为的关系  

Relationship between methylation of microRNA-335 and poor biological behaviour in gastric cancer

作　　者：时明霞[1] 沙拉依丁·沙力克江 窦怀豹 陈琨 张家魁[1] Shi Mingxia;Shalayiding·Shalikejiang;Dou Huaibao;Chen Kun;Zhang Jiakui(Department of Gastrointestinal Surgery,the Fourth Affiliated Hospital of China Medical University,Liaoning Shenyang 110032,China;Department of General Surgery,the Tacheng Hospital of China Medical University,Xinjiang Tacheng 834700,China)

机构地区：[1]中国医科大学附属第四医院第二普通外科,辽宁沈阳110032 [2]中国医科大学塔城医院普通外科,新疆塔城834700

出　　处：《现代肿瘤医学》2019年第18期3199-3204,共6页Journal of Modern Oncology

基　　金：辽宁省自然科学基金指导计划项目(编号:20170520034)

摘　　要：目的:探讨miR-335基因启动子区异常甲基化状态对胃癌细胞系中miR-335表达水平的影响,以及miR-335基因启动子区甲基化状态对胃癌细胞侵袭,迁移,以及增殖能力的影响。方法:1株永生化胃黏膜上皮细胞系(GES-1)和4株胃癌细胞系(SGC-7901,MKN-45,BGC-823和AGS)。实时荧光定量PCR(qRT-PCR)检测胃癌细胞株miR-335及CRKL的表达水平。甲基化特异性PCR(MSP)方法检测胃癌细胞株miR-335的基因启动子区甲基化状态。应用MTT方法检测恢复miR-335表达对胃癌细胞增殖能力的影响,Transwell侵袭迁移实验及划痕愈合实验分析恢复miR-335表达对胃癌细胞系侵袭及迁移能力的影响。结果:MSP实验结果表明,MKN-45、SGC-7901和BGC-823细胞系均存在基因启动子区异常的高甲基化状态,AGS细胞系基因启动子区亦呈部分高甲基化状态。去甲基药物5-aza-2′-deoxycytidine处理后胃癌细胞miR-335的表达水平可升高2~3倍。Transwell侵袭迁移实验及划痕愈合实验表明miR-335表达水平恢复后SGC-7901细胞的侵袭和迁移能力明显降低。MTT实验结果表明5-aza-2′-deoxycytidine处理后的SGC-7901细胞系与对照组相比,增殖能力显著降低。结论:miR-335启动子区的异常高甲基化状态抑制了miR-335在胃癌细胞系中的表达,恢复miR-335的表达水平可以抑制胃癌细胞的增殖,迁移和侵袭能力。miR-335为胃癌的肿瘤抑制因子。Objective:To investigate the role of miR-335 methylation and expression in gastric cancer(GC) cell lines,the functional impact of miR-335 ectopic expression on gastric cancer cells invasion,apoptopsis and proliferation.Methods:Relative expression of miR-335 in 4 gastric cancer cell lines was confirmed by real-time quantitative reverse transcriptase-PCR(qRT-PCR) compared with controls.Methylation-specifc PCR(MSP) was used to evaluate the DNA methylation status in the CpG islands upstream of miR-335 in gastric cancer cell lines.Gastric cancer cell lines were treated with 5-aza-2′-deoxycytidine and the effects upon cell proliferation,migration and invasion were investigated.Results:We observed aberrant cancer-specific methylation in the upstream CpG-rich regions of miR-335,which dramatically silenced its transcriptional activity in gastric cancer cell lines.Furthermore,we demonstrated that restoration of miR-335 in GC inhibited tumor cell migration,invasion and proliferation.Conclusion:miR-335 may be silenced by promoter hypermethylation and functions as a tumor suppressor and plays a role in inhibiting tumor cell migration,invasion and proliferation.

关 键 词：胃癌 微小RNA miR-335 甲基化 

分 类 号：R735.2[医药卫生—肿瘤]