结直肠癌组织miR34a启动子区甲基化状态的临床意义探讨

Clinical significance of miR-34a promoter methylation status in colorectal cancer

目的探讨结直肠癌组织miR34a启动子区甲基化状态的临床意义。方法收集48例行根治性切除术的结直肠癌患者的癌组织及癌旁正常组织,采用甲基化特异性PCR(MSP)法检测miR-34a启动子区CpG岛甲基化状态,分析其与患者临床特征及预后的关系。结果结直肠癌组织与癌旁正常组织中miR-34a启动子区甲基化率分别为47.9%、43.8%,差异无统计学意义(P>0.05)。结直肠癌组织miR-34a启动子区甲基化状态与患者性别、年龄、肿瘤位置、肿瘤最大直径、远处转移等均无关(均P>0.05);与淋巴结转移、TNM分期等均有关(均P<0.05)。结直肠癌组织miR-34a启动子区甲基化患者总生存率、无病生存率均低于非甲基化患者(均P<0.05)。远处转移是影响结直肠癌患者预后的独立危险因素(P<0.05),但miR-34a启动子区甲基化状态不是影响结直肠癌患者预后的独立危险因素(P>0.05)。结论结直肠癌组织miR-34a启动子区甲基化状态与患者淋巴结转移、TNM分期及预后有关,可能参与肿瘤进展转移过程的调控。

Objective To investigate the clinical significance of miR-34a promoter methylation status in colorectal cancer.Methods Methylation-specific polymerase chain reaction(MSP)was used to detect the methylation level of CpG island in the promoter region of miR-34a in colorectal cancer and adjacent tissues of 48 patients who underwent radical resection in our hospital.The correlation between the methylation level and clinical characteristics and prognosis was analyzed.Results The methylation rates of the promoter of miR-34a in colorectal cancer tissues and adjacent normal tissues were 47.9%and 43.8%respectively(P>0.05).The methylation status was not related to age,sex,location of tumors,maximum diameter of tumors and distant metastasis(all P>0.05),while was correlated with lymph node metastasis and TNM staging(both P<0.05).The overall survival(OS)rate and disease-free survival(DFS)rate of patients with methylation were lower than those of patients with non-methylation(both P<0.05).Distant metastasis was an independent prognostic factor in patients with colorectal cancer(P<0.05),but the methylation status of miR-34a was not(P>0.05).Conclusion The CpG methylation of miR-34a is associated with lymph node metastasis,the staging and the prognosis of colorectal cancer patients.It may be involved in the regulation of the progression and metastasis of colorectal cancer.