【摘要】 目的　研究端粒酶催化亚单位 (hTERT)和p5 3基因在大肠癌组织中的表达 ,进而探讨大肠癌发生过程中端粒酶活化的分子机制。方法　分别采用原位逆转录聚合酶链反应 (RT PCR)和端粒重复序列扩增 (TRAP)法检测 46例大肠癌及其相应正常组织中hTERTmRNA表达与端粒酶活性。用免疫组化S P法测定上述组织标本中的p5 3蛋白表达。结果　hTERTmRNA与端粒酶活性在大肠癌组织中阳性表达率分别为 87 0 % (4 0 /4 6)和 80 4% (3 7/4 6) ,均明显高于相应正常组织 (P <0 .0 1)。大肠癌中hTERYmRNA表达与端粒酶活性明显相关 (r=0 .696,P <0 .0 1)。p5 3蛋白在大肠癌中阳性表达率为 67 4% (3 1/4 6) ,而正常组织未见阳性表达 ,二者比较差异有显著性 (P <0 .0 1)。大肠癌组织p5 3蛋白表达与hTERTmRNA表达或端粒酶活性无显著相关性 (P >0 .0 5 )。结论　端粒酶激活与大肠癌的发生密切相关 ,hTERTmRNA表达上调可能在大肠癌端粒酶活性调节中发挥重要作用。p5 3蛋白表达增强可能与端粒酶激活无直接相关更多还原

【Abstract】 Aim To investigate the expression of human telomerase reverse transcriptase (hTERT) and p53 oncogene in colorectal cancerous tissues,and investigate the mechanisms of telomerase activation in the development of colorectal cancer.Methods hTERTmRNA and telomerase activity were detected in tissues samples from 46 cases with colorectal cancers and their matched normal tissues by in situ reverse transcription polymerase chain reaction (ISRT PCR) and telomal repeat amplification protocol(TRAP) respectively.The p53 oncoprotein was examined in these samples with immunohistochemical method.Results The overexpression rate of hTERTmRNA and telomerase activity were 87.0% and 80.4% in 46 samples of colorectal cancers respectively,significantly higher than those of normal tissues group( P<0.01 ).There was a significant correlation between the expression of hTERTmRNA and telomerase activity( r=0.696,P<0.01 ).It was found that p53 oncoprotein was positive in 67.4%(31/46) samples of colorectal cancers and negative in all those of normal tissues( P<0.01). The expressions of p53 oncoprotein and hTERTmRNA or telomerase activity were noticed to be not correlated( P>0.05). Conclusions The results suggest that telomerase activation and up regulation of hTERTmRNA may play a critically important role in the carcinogenesis of colorectal cancer.The p53 oncoprotein may unaffect telomerase activity during更多还原