膀胱癌和肾癌组织中RASSF1A基因的甲基化改变

目的研究RASSF1A基因启动子的甲基化状态及在膀胱癌和肾癌发生中的作用。方法采用甲基化特异性PCR(MSP)技术检测45例手术切除的膀胱癌组织和相应癌旁正常组织标本、9例电切膀胱癌组织、3例非肿瘤患者正常膀胱组织、12例肾癌组织和相应癌旁正常组织标本中RASSF1A基因的甲基化情况。结果膀胱癌组织中RASSF1A基因异常甲基化55.6%(30/54),其中手术切除组57.8%(26/45),电切癌组织异常甲基化4例,癌旁正常组织基因异常甲基化1例;肾癌组织中基因异常甲基化66.7%(8/12),相应癌旁正常组织中未发现基因甲基化。3例正常膀胱组织标本中未发现基因异常甲基化。膀胱癌组织中RASSF1A基因甲基化率有随组织分期升高的趋势,但与临床病理参数间无明显相关性。结论膀胱癌和肾癌组织中RASSF1A基因启动子高度甲基化,表明该基因甲基化可能与2种肿瘤的发生相关。

Alteration of RASSF1A gene methylation status in bladder cancer and renal carcinoma

Objective To investigate the methylation status of the promoter of RASSF1A gene in the tissues of bladder cancer and renal carcinoma and its role in tumorigenesis. Methods Methylation specific PCR (MSP) was used to examine the methylation status of RASSF1A in bladder cancer and renal carcinoma.The specimen included 45 cases of bladder cancer tissues and paired adjacent normal tissues from cystectomy,9 cases of bladder cancer tissues from microresection,3 cases of normal bladder tissues from people without tumor,12 cases of renal carcinoma tissues and paired adjacent normal tissues. Results 30 of 54(55.6%)bladder cancer tissues showed RASSF1A gene aberrant methylation.Of which,26 of 45 ( 57.8 %) bladder cancer tissues from cystectomy showed aberrant methylation,while one of the paired normal tissues showed gene methylation,4 of 9 (44.4%) bladder cancer tissues from microresection showed gene methylation.Eight of 12(66.7%)renal carcinoma tissues showed aberrant methylation,while none of the paired adjacent normal tissues showed gene methylation.None of the three normal bladder tissues showed aberrant methylation.There was no significant correlation between the methylation status and the clinical pathological parameters in bladder cancer tissues from cystectomy,though there was a trend that more frequent methylation was detected in higher stage bladder cancer. Conclusions Hypermethylation of RASSF1A gene in bladder cancer and renal carcinoma suggeste its possible role in the tumorigenesis of both tumors.