SOCS-3基因在结肠癌中的表达及其甲基化测定

Expression of SOCS-3 in colon cancer and determination of its methylation

目的通过对SOCS-3基因在结肠癌和癌旁组织中的表达及其启动子甲基化状态的测定,探讨其与结肠癌发生、发展和转移的关系。方法收集40例结肠癌患者的肿瘤标本、20例癌旁组织及10例正常结肠组织,运用甲基化特异性PCR测定SOCS-3基因CpG岛甲基化状态,同时运用实时定量PCR分析SOCS-3基因在结肠癌组织中的表达水平。结果40例结肠癌组织中有34例(85%)存在SOCS-3基因CpG岛的异常甲基化,癌旁组织中有2例(10%),而正常结肠组织中未检测到SOCS-3基因CpG岛的异常甲基化;结肠癌组织中SOCS-3基因CpG岛甲基化组与无甲基化组相比,其SOCS-3基因的相对表达量明显减少(P<0.05),表明SOCS-3基因CpG岛甲基化可导致SOCS-3基因表达降低。SOCS-3基因CpG岛甲基化与性别、年龄无关(P>0.05),而与肿瘤病理分级、TNM分期有关(P<0.05)。结论结肠癌中存在SOCS-3基因CpG岛异常甲基化,且CpG岛的甲基化导致其基因表达降低。SOCS-3基因CpG岛甲基化可能参与了结肠癌的发生、发展和转移。

Objective To detect the expression of SOCS-3 gene in colon cancer and its methylation,and to explore the role of SOCS-3 in the occurrence and development of colon cancer. Methods A total of 40 cases of human colon cancer tissues,20 cases of tumor-adjacent tissues and 10 cases of human normal colon tissues were collected.The CpG island methylation status of SOCS-3 gene was detected by methylation specific PCR.Subsequently,the expression of SOCS-3 gene in human colon cancer tissues was detected by real time RT-PCR. Results Methylation-specific PCR results revealed that abnormal CpG island methylation of SOCS-3 gene was found in 34 cases of colon cancer tissues（85%）,two cases（10%） of tumor-adjacent tissues,and no abnormal CpG island methylation of SOCS-3 in normal colon tissues.Compared with the non-methylated group,the relative expression of SOCS-3 gene in methylated group significantly reduced.SOCS-3 gene CpG island methylation could lead to reduce expression of SOCS-3 gene.SOCS-3 gene CpG island methylation was not related to gender and age（P0.05）,but related to tumor histological grade and TNM stage（P0.05）. Conclusion Abnormal CpG island methylation of SOCS3 gene was found in colon cancer tissues,that leads to reduce expression of SOCS-3 gene.Abnormal CpG island methylation of SOCS-3 gene may play an important role in the occurrence,development and metastasis of colon cancer.