大肠癌miR-195表达变化与临床病理学特征的关系

The relationship between miR-195 expression and clinical pathological characteristics of colorectal cancer

目的 探讨大肠癌miR-195表达变化与临床病理学特征的关系.方法 采用实时荧光定量PCR技术检测miR-195在50例大肠癌患者癌组织及对应癌旁正常组织（距离癌组织＞5 cm）中的表达水平,分析其表达情况与临床病理因素的相关性.结果 50例大肠癌患者中共检出miR-195 CpG岛甲基子表型阳性者29例,阳性率为58％（29/50）.50例大肠癌患者中有34例出现miR-195在大肠癌组织中的表达较癌旁正常组织下调,即T/N＜2.miR-195在大肠癌组织中及癌旁正常组织中的表达水平分别为0.837±1.145和2.236±2.468,差异有统计学意义（P＜0.05）.miR-195在大肠癌组织中的低表达与患者的年龄、性别、大肠癌部位、浸润深度无关（P＞0.05）,与患者淋巴结转移、TNM分期有关（P＜0.05）,在发生淋巴结转移或TNM分期晚的患者中表达明显下调.结论 miR-195在大肠癌组织中的表达呈普遍低表达的趋势,miR-195可能在大肠癌中扮演抑癌基因的角色.miR-195启动子区高甲基化可能是导致miR-195在大肠癌组织中表达下调及参与大肠癌发生发展的原因之一.

Objective To explore the relationship between miR-195 expression and clinical pathological characteristics of colorectal cancer.Methods The expression of miR-195 in 50 cases of colorectal cancer tissue and adjacent non-tumor mucosa （5 cm away from the cancer tissue） was detected by real time PCR.The relationship between miR-195 expression and clinical pathological characteristics of colorectal cancer was analyzed.Results miR-195 CpG island methylate phenotype was positive in 58％ （29/50） of patients with colorectal cancer.The expression level of miR-195 in 34 patients colorectal cancer tissue was lower than that in adjacent non-tumor mucosa,that was T/N ＜ 2.The expression level of miR-195 in carcinoma tissue was 0.837 ± 1.145,comparing with adjacent non-tumor mucosa （2.236 ± 2.468）,showing significant difference （P ＜ 0.05）.Down-regulated expression of miR-195 in carcinoma tissue was independent of age,gender,site（P ＞ 0.05）,and related to lymphnode metastasis and TNM stage（P ＜ 0.05）.Patients with lymph node metastasis and advanced TNM stage showed significantly reduced expression of miR-195.Conclusions The tendency of common low expression level of miR-195 in human colorectal cancer.MiR-195 maybe play as suppressor gene in human colon carcinoma.Hypermethylation of miR-195 promoter may be one of reasons leading to down-regulation of miR-195 in colorectal cancer tissues and participated in the occurrence and development of human colon carcinoma.