胆汁中突变基因与大肠癌肝转移关系的研究

Study of the relation between mutant gene in bile and hepatic metastasis of large intestinal carcinoma

目的探讨胆汁中的点突变基因对诊断大肠癌肝转移的价值。方法采用ＰＣＲＳＳＣＰ及ＤＮＡ测序技术，检测大肠癌患者原发灶、肝转移灶、胆汁中相同突变位点的ｐ５３、ｋｒａｓ基因。结果在５０例大肠癌中，检出有ｐ５３、ｋｒａｓ基因突变３８例（７６０％）。其中有ｐ５３基因突变２８例（５６０％），ｋｒａｓ基因突变１６例（３２０％）。在１２例出现肝转移者的胆汁中检出有与原发灶相同的点突变基因者１０例（８３３％）。结论大肠癌肝转移癌细胞是来自与原发灶有相同点突变基因的瘤细胞克隆。检测胆汁中与原发灶相同的点突变基因，可能成为早期诊断大肠癌肝转移的一种方法。

Objective To study the value of point mutant genes in the diagnosis of hepatic metastasis of large intestinal carcinoma. Methods Techniques of PCR SSCP and DNA sequencing were used to detect point mutations of p53 and k ras genes in primary focus, hepatic metastic focus, and bile. Results 50 cases of large intestinal cancer were detected.38 cases (76 0%) had p53 and k ras gene mutations. p53 gene mutations were detected in 28 cases (56 0%) and k ras gene mutations in 16 cases (32 0%).The same point mutant genes in bile with primary focus were detected in 10 out of 12 patients with hepatic metastasis (83 3%). Conclusions The tumor cells of hepatic metastasis show the same clonal origin with primary focal cells that had same point mutant genes.Detection of the point mutant genes in bile is of value in the diagnosis of hepatic metastasis of large intestinal carcinoma.