【摘要】 目的 :探讨错配修复基因变异与中国人散发性大肠癌发病年龄之间的关系。方法 :随机选取 1 0 0例临床初诊的散发性大肠癌患者 ,配对提取手术切除的癌组织和同源正常组织的基因组DNA ,检测并分析癌细胞微卫星DNA不稳定性 (MSI)。结果 :46/1 0 0 (46 % )的癌组织MSI阳性 (MSI+ ) ,其中 1 8%为MSI+ H ,2 8%MSI+ L。按年龄分组分析表明 ,发病年龄 <45岁的大肠癌患者中MSI+ 检出率明显高于≥ 65岁的大肠癌患者 (P <0 .0 5) ,且MSI+ 的检出率与患者的发病年龄呈负相关 (r =- 0 .95 ,P <0 .0 5) ,但与癌细胞的分化及患者的临床分期无关。结论 :中国人散发性大肠癌中错配修复基因功能的丧失可能出现在癌症发生的早期 ,可能参与构成部分散发性大肠癌发病的遗传背景因素更多还原

【Abstract】 Purpose:To investigate the relationship between inactivity of mismatch repair system in colorectal cancer (CRC) in Chinese patients and their age at onset of CRC.Methods:Genomic DNA extracted from colorectal cancer tissues and their normal colon tissues were subjected to analysis for microstallite instability (MSI) in six of DNA markers in 100 colorectal cancer patients.Results:Microsatellite instability positive (MSI + ) was detected in 46 out of 100 (46%) of CRC tissues, MSI + H in 18/100 (18%) and MSI + L in 28/100 (28%). The rate of MSI + in the CRC patients who are younger than 45 years old is higher than that in older patients (≥65 years ) ( P <0.05). A negative correlation was found between the rate of MSI + and the patient’s age at onset of CRC. (r=-0.95, P <0.05).On the other hand, MSI + rates detected in cancer tissues were not related to the grade of cancer cell differentiation and with clinical stage of CRC. Conclusions:Defect of mismatch repair system may occur in the early stage of carcinogenesis in CRC. It may be one of the etiological factors of sporadic colorectal cancer in the Chinese. [更多还原