GSTP1基因在前列腺癌组织中的表达及甲基化状态研究

目的：研究谷胱苷肽S转移酶P1（glutathione S transferase pi,GSTP1）在前列腺癌的表达情况并分析其甲基化状态.方法：采用免疫组织化学方法检测GSTP1在50例前列腺癌石蜡标本中的表达情况,并用甲基化特异性聚合酶链反应（methylation-specific polymerase chain reaction, MSP）方法分析GSTP1基因启动子区5＇端CpG岛非甲基化和甲基化的状态.结果： GSTP1在前列腺癌表达的阳性率为18.0%,明显低于癌旁正常前列腺腺体的阳性率（76.0%）,P=0.000.GSTP1基因启动子区非甲基化发生率为86%（43/50）,50例前列腺癌均未扩增出甲基化特异性产物.结论： GSTP1阴性表达有望成为前列腺癌诊断的一项辅助性新指标.国内前列腺癌GSTP1基因的高频率表达缺失可能与GSTP1基因启动子区甲基化无关,因本组病例数较少,还需进一步积累资料证实.

Expression and methylation of the GSTP1 gene in prostate carcinoma

OBJECTIVE:To investigate the expression and analyze methlytion status of GSTP1 gene in prostate carcinoma. METHODS:The immunohistochemistry technigque was used to detect the expression of GSTP1 in prostate carcinoma. The methlytion and unmethlytion status of 5' CpG island of GSTP1 gene were analysed by methylation-specific polymerase chain reaction(MSP) as a main methed. RESULTS: The positive expression of GSTP1 in prostate carcinoma was 18.0% and it was much lower than that in normal glands beside carcinoma (76.0%),P=0.000. The rate of unmethylation of GSTP1 gene promoter in prostate carcinoma was 86%(43/50)by MSP,while none of patients with aberrant promoter CpG islands methylation status of GSTP1 gene was found in this group. CONCLUSIONS: The negative expression of GSTP1 may become a new adjunct diagnostic marker in prostate carcinoma.The absent expression of GSTP1 probably has no relationship with GSTP1 gene promoter CpG islands methylation in Chinese patients with prostate carcinoma, however, it remains to be further clarified by more studies.