MicroRNA-335的表遗传学调控机制及其与胃癌患者临床病理特征的关系  

Epigenetic regulation of microRNA-335 and its clinical significance in gastric cancer

作　　者：张家魁[1] 李永双[1] 刘继超[1] 张春东[1] 戴冬秋[1] 

机构地区：[1]中国医科大学附属第四医院胃肠外科,辽宁沈阳110032

出　　处：《现代肿瘤医学》2016年第16期2557-2561,共5页Journal of Modern Oncology

摘　　要：目的:探索miR-335基因启动子区甲基化状态对胃癌组织及细胞系中miR-335表达水平的影响,以及miR-335基因启动子区甲基化状态与胃癌患者临床病理特征以及预后的关系。方法:收集2012年7月1日-2014年7月1日中国医科大学附属第四医院就诊经病理诊断为原发性胃癌并行根治性手术的108例新鲜胃癌组织及配对癌旁组织,1株永生化的胃黏膜上皮细胞系(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)检测胃癌细胞株及108例胃癌患者肿瘤组织中miR-335的表达水平。甲基化特异性PCR(MSP)方法检测胃癌细胞系及胃癌患者肿瘤组织中miR-335的基因启动子区甲基化状态。分析miR-335基因启动子区甲基化状态对胃癌患者临床病理特征的影响。结果:qRT-PCR检测结果显示,miR-335在胃癌细胞株中的表达水平显著低于正常胃黏膜上皮细胞株GES-1[MKN-45,0.154±0.016-fold(P<0.01);SGC-7901,0.138±0.013-fold(P<0.01);BGC-823,0.432±0.076-fold(P<0.01);AGS,0.749±0.072-fold(P=0.01)]。miR-335在108例胃癌组织中的表达水平较癌旁组织存在明显下降,差异显著(P<0.001)。MSP的实验结果表明,MKN-45、SGC-7901、AGS和BGC-823细胞株均存在基因启动子区异常高甲基化状态。miR-335基因启动子区的高甲基化状态与肿瘤大小(P=0.004)、淋巴结转移(P=0.046)、淋巴管浸润(P=0.001)和miR-335低表达(P<0.001)显著相关。结论:miR-335启动子区的高甲基化状态抑制了miR-335在胃癌细胞中的表达,miR-335的基因启动子区异常高甲基化状态与胃癌患者的肿瘤大小、淋巴结转移以及淋巴管浸润显著相关。Objective：To investigate the role of miR - 335 methylation and expression in gastric cancer cell lines and gastric tumor tissues,the clinicopathological and prognostic values of miR - 335 methylation in patients with gas-tric cancer（GC）. Methods：One hundred and eight pairs of fresh GC tissue and adjacent non - tumor gastric tissues were obtained from patients with a diagnosis of primary GC and then underwent elective surgery in The Fourth Affilia-ted Hospital of China Medical University（Shenyang,China）between June 2012 and June 2014. Relative expression of miR - 335 in 4 gastric cancer cell lines and in 108 gastric cancer tissues was detected by real - time quantitative re-verse transcriptase - PCR（qRT - PCR）compared with controls. Methylation - specifc PCR（MSP）was used to evalu-ate the DNA methylation status in the CpG islands upstream of miR - 335 in gastric cancer cell lines and tissues. Re-sults：In 108 GC patients,the miR - 335 level was remarkably downregulated in GC tissues compared with paired ad-jacent nontumorous tissues（P ﹤ 0. 001）. miR - 335 was downregulated in gastric cancer cell lines SGC - 7901,MKN- 45,BGC - 823 and AGS compared with a normal gastric epithelial cell line GES - 1[MKN - 45,0. 154 ＆#177; 0. 016 -fold（P ﹤ 0. 01）. SGC - 7901,0. 138 ＆#177; 0. 013 - fold（P ﹤ 0. 01）. BGC - 823,0. 432 ＆#177; 0. 076 - fold（P ﹤ 0. 01）. AGS, 0. 749 ＆#177; 0. 072 - fold（P = 0. 01）]. MSP of miR - 335 in all 4 GC cell lines verified the marked methylation of the promoter region of miR - 335. Hypermethylation of the miR - 335 gene promoter region was associated with tumor size （P = 0. 004）,metastasis lymph node（P = 0. 046）,miR - 335 expression level（P ﹤ 0. 001）and invasion into lym-phatic vessels（P = 0. 001）. Conclusion：miR - 335 may be silenced by promoter hypermethylation and functions as a tumor suppressor in gastric cancer. Hypermethylation status of miR - 335 are associated with poor clinicopathological characteristics in gastric ca

关 键 词：胃癌 微小RNA miR-335 甲基化 

分 类 号：R735.2[医药卫生—肿瘤]