口腔鳞癌K-ras基因测序分析及p21~(ras)蛋白的表达

目的:探讨K-ras基因在口腔鳞癌中的序列改变和p21ras蛋白的表达。方法:采用聚合酶链反应直接测序检测口腔鳞癌K-ras基因外显子1、2突变,免疫组织化学法检测口腔鳞癌组织、癌旁正常组织p21蛋白的表达。结果:30例口腔鳞癌中4例(13.3%)存在K-ras基因突变,突变方式为C→T转换,突变位点在第6位和第79位密码子,口腔鳞癌组织p21ras蛋白阳性率为73.3%(22/30),高于癌旁正常组织20%(6/30)。结论:口腔鳞癌中K-ras基因的突变谱较广,K-ras基因突变和p21蛋白表达与口腔鳞癌发生发展有关。

SEQUENCE ANALYSIS OF K-RAS AND p21ras PROTEIN EXPRESSION IN ORAL SQUAMOUS CELL CARCINOMAS

Objective: To investigate DNA sequence changes of K-ras gene and p 21ras protein overexpression in oral squamous cell carcinoma (OSCC). Methods: DNA sequencing m ethods were used to investigate mutational spectra of K-ras gene exons 1,2 and immunohistochemistry technique used to analyze expression of p21 protein from OSCC and control specimens. Results: It showed t hat K-ras mutations were 4/30 (13.3 %) and mutation mode was C→T transition and the point mutations occur ed at cordons 6 and 79 from OSCC tissue. The positive rate of p21ras protein expression in OSCC was 73.3 %(22/30), which was higher than that of normal tissue near the carcinoma 20 %(6/30). Conclusions: T here are wide K-ras spectra in OSCC. K-ras gene mutations and p21 protein overexpression may play a role in occurrence and development of OSCC.