摘要目的 检测结直肠癌组织中p27基因启动子区CpG岛甲基化水平及其表达,并结合其临床病理参数进行分析,探讨其在结直肠癌发生发展中的作用.方法 应用甲基化特异性聚合酶链反应分析技术检测106例结直肠癌组织及其正常结直肠黏膜组织、22例结肠腺瘤组织中p27基因启动子甲基化,用免疫组织化学SP方法检测其蛋白表达.结果 本组结直肠癌组织中p27甲基化阳性率为59.4%(63/106),结肠腺瘤组织中为18.2%(4/22),而正常结直肠黏膜组织中为3.8%(4/106),前组与后两组之间相比差异有统计学意义(P＜0.05).低分化组结直肠癌组织中p27甲基化阳性率明显高于高中分化组(48.0%比24.7%,P＜0.05);Dukes-A+B期组与C+D期组之间相比差异有统计学意义(20.0%比41.2%,P＜0.05);有无淋巴结转移两组之间的阳性率相比差异有统计学意义(41.5%比23.1%,P＜0.05);浸润深达浆膜层的结直肠癌组织中的甲基化阳性率与未达浆膜层组相比差异无统计学意义(32.5%比24.1%,P＞0.05).结论 结直肠癌组织中存在p27基因启动子甲基化.p27基因的高甲基化与结直肠癌分化程度、浸润深度、Dukes分期及有无淋巴结转移有关.

abstractsObjective To investigate the relationship between p27 gene methylation and pathology of colorectal carcinoma. Methods p27 gene methylation promotor region and p27 protein expression were detected respectively by methylation specificity polymerase chain reaction and immunohistochemical staining SP in 106 cases of colorectal carcinoma and each adjacent normal mucous membrane tissue and 22 cases of colorectal adenoma tissue. Results The positive expression rate of p27 gene methylation was statistically different in colorectal carcinoma tissue compared with normal mucous membrane and colorectal adenoma tissue (P＜0.05). Their positive expression rate were 59.4% (63/106), 18.2% (4/22) and 3.8%(4/106) respectively in colorectal carcinoma tissue,colorectal adenoma and normal mucous membrane tissue (P ＜ 0. 05). p27 gene methylation in poorly differentiated group was significantly higher than that in welldifferentiated group (48.0% vs. 24. 7%, P ＜0. 05), in Dukes-A + B stage group was significantly lower than that in Dukes C + D stage group(20. 0% vs. 41.2%, P ＜ 0. 05 ), and it was higher in lymph nodes metastases group than that in lymph nodes negative group(41.5% vs. 23. 1%, P ＜0. 05), that in positive serosa infiltration group was higher than negative serosa infiltration group(32. 5% vs. 24. 1%, P ＞ 0. 05 ).Conclusions Methylated p27 gene protein expression in colorectal carcinoma was significantly higher than normal mucous membrane and colorectal adenoma tissue. The methylation rate of p27 gene in colorectal carcinoma was significantly associated with tumor differentiation, invasive depth, Dukes stage, lymph node metastasis.