RASSF1基因转录本A和C的表达与卵巢癌关系的研究

Expression of RASSF1A and RASSF1C transcripts in human primary ovarian cancers

目的探讨RASSF1基因转录本A和C在多个卵巢癌细胞系和卵巢癌组织中所起的作用。方法应用逆转录聚合酶链反应(RT PCR)和激光捕获显微切割技术检测3个卵巢癌细胞系和80例人原发卵巢上皮性恶性肿瘤组织中RASSF1A和RASSF1CmRNA的表达。结果RASSF1A mRNA在卵巢癌SK OV3细胞中表达缺失;RASSF1A和RASSF1C在人卵巢癌组织中的表达率分别为40.0%(32/80)和91.3%(73/80)。RASSF1AmRNA的表达在浆液性癌、黏液性癌和内膜样癌组织中分别是41.2%(20/48),38.1%(8/21)和36.4%(4/11),P>0.05;临床Ⅰ期和Ⅱ期分别为71.4%和75.0%(10/14,9/12),明显高于临床Ⅲ期和Ⅳ期(26.7%、12/45和14.1%,1/9),P<0.05;高和中分化组分别为58.6%和50.0%(17/29,10/20),明显高于低分化组(16.1%,5/31),P<0.05。结论卵巢癌细胞和人原发卵巢癌组织中存在RASSF1AmRNA表达的缺失,RASSF1A的表达与卵巢癌的临床分期和组织学分级有关,可能作为一种新的抑癌基因在卵巢癌的发生和发展过程中起重要作用,RASSF1AmRNA的缺失提示预后不良。

Objective To investigate the expression of two major alternative transcripts of RASSF1 gene (RASSF1A and RASSF1C) in human primary ovarian cancers and their biological implication as a new tumor suppressor gene. Methods Reverse transcription - polymerase chain reaction (RT-PCR) and laser capture microdissection (LCM) were used to determine mRNA expression of the two major alternative transcripts of RASSF1 gene (RASSF1A and RASSF1C) in 3 ovarian cancer cell lines and 80 cases of primary ovarian cancers. Results RASSF1A mRNA was undetectable in SK-OV-3 cell line. Expression of RASSF1A and RASSF1C in 80 primary ovarian cancers were 40.0%(32/80) and 91.3%(73/80) respectively. RASSF1A mRNA expression was detectable more frequently in stage Ⅰ and Ⅱ (71.4%, 10/14; 75.0%, 9/12) than in stage Ⅲ and Ⅳ ovarian cancers (26.7%, 12/45; 14.1%, 1/9)(P<0.05). The expression level was also higher in well and moderately differentiated tumor groups (58.6%, 17/29; 50.0%10/20) than in poorly differentiated tumor group (16.1%, 5/31)(P<0.05). Conclusion There is a preferential loss of RASSF1A expression in human ovarian cancers and its expression is correlated with the tumor stage and the degree of histological differentiation which, as a tumor suppressor gene, might play an important role in the tumorigenesis of human primary ovarian cancer.