Survivin和RASSF1A基因在大肠癌中的表达及其临床意义

The Expression and Clinical Significance of the Survivin and RASSF1A Genes in the Colorectal Carcinoma Tissues

为研究大肠癌组织中生存素（survivin）基因与Ras相关区域家族1A（RASSF1A）基因表达与大肠癌发生、发展的关系，利用逆转录PCR技术，测定60例大肠癌组织及20例癌旁组织中survivin基因与RASSF1A基因的mRNA表达情况；利用甲基化特异性PCR（MSP）技术对RASSF1A启动子甲基化情况进行了鉴定。结果显示，survivin在大肠癌组织中阳性表达率为46．7％（28／60），在正常癌旁组织中只有1例表达，其表达与肿瘤转移、分化程度及Dukes分期相关（P〈0．05）。RASSF1A在大肠癌组织中的缺失率为30．0％（18／60），在正常癌旁组织中均有表达，其表达与肿瘤转移、分化程度及Dukes分期相关（P〈0．05）。但survivin与RASSF1A二者表达无相关性。RASSF1A启动子甲基化率为45．0％（27／60），与肿瘤分化程度相关（P〈0．05），并且与RASSF1A基因的表达缺失密切相关（P〈0．001）。结果表明，RASSF1A启动子甲基化是导致RASSF1A基因表达缺失的主要原因，RASSF1A和survivin基因的异常表达在大肠癌的发生、发展中起重要作用，联合检测survivin和RASSF1A基因及其甲基化有可能作为反映大肠癌进展和预后的生物学指标。

The expression of the survivin and RASSF（RAS association domain family） 1A genes in the colorectal carcinoma tissues of 60 patients and in the adjacent carcinoma tissues of 20 patients was measured with reverse transcription polymerase chain reaction（PCR） technic, while the methylation of RASSFIA promoter was assessed by methylation specific PCR（MSP）. As results,the expression rate of survivin in the colorectal carcinoma tissues was 46.7% （28/60） and the expression of survivin in adjacent carcinoma tissues was found only in one case,and the survivin expression was correlated with carcinoma metastasis, differentiation extent and Dukes staging（ P 〈0. 05）;while the absence rate of RASSF1A expression in colorectal carcinoma tissues was 30% （18/60）,and RASSFIA expression was found in all the adjacent colorectal carcinoma tissues and its expression was correlated with carcinoma metastasis, diffentiation extent and Dukes staging（ P 〈0.05） ;the expression of survivin and the expression of RASSF1A were not correlated each other;the methylation rate of RASSFIA promoter was 45.0%（27/60） and was correlated with carcinoma differentiation extent（ P 〈0.05） and was closely correlated with the absence rate of RASSF1A expression（ P 〈0.01）. It is concluded that the methylation of RASSF1A promoter is the main cause of the RASSF1A expression loss;the abnormal expression of survivin and RASSF1A plays an important role in the occurrence and development of colorectal carcinoma; and the combined measurement of survivin and RASSFIA （including RASSFIA colorectal carcinoma development promoter methylation） may serve as and prognosis. the biological indexes of reflecting colorectal carcinoma development and prognosis.