K-ras对girdin蛋白表达的调控机制及二者在结直肠癌中的表达

Regulatory mechanisms of K-ras to girdin in COS7 cells and expression of K-ras and girdin in colorectal carcinoma

目的:研究K-ras对COS7细胞girdin蛋白的调控机制,并检测结直肠癌组织中k-ras和girdin的表达。方法:通过病毒载体构建稳定高表达K-ras的COS7细胞,采用Western blot方法检测稳定细胞株和结直肠癌组织中K-ras、girdin及其相关蛋白的表达。结果:高表达K-ras的COS7细胞形态不规则。Western blot实验结果显示在高表达K-ras时其下游的信号蛋白p-ERK1/2和p-Stat3的蛋白水平都明显增加,同时girdin的表达量也明显增加;当加入K-ras siRNA后,p-ERK1/2、p-Stat3和girdin的表达量也随之减少。对7例结直肠癌组织和相应癌旁组织用Western blot检测结果显示,有5例组织在K-ras高表达的同时girdin的表达量也随之增加。结论:通过细胞和组织实验结果推测K-ras蛋白通过Ras-ERK1/2-Stat3信号通路实现对girdin蛋白的调控,并为临床上与K-ras相关的肿瘤治疗提供一定的参考。

AIM ： To investigate molecular regulatory mechanism of K-ras to girdin protein in C0S7 cells andexpression of K-ras and girdin in colorectal carcinoma tissues. METHODS ： The lentiviral vector carrying K-ras gene was constructed and transfected in the C0S7 cells. The expression of K-ras, girdin proteins and other related proteins in C0S7 cells and colorectal carcinoma tissues was observed by Western blot. RESULTS ： The C0S7 cells with K-ras over-expres-sion showed an irregular cell morphology. The results of Western blot indicated that the downstream signal protein levels of p-ERKl/2, p-Stat3 and girdin were significantly increased in the C0S7 cells with K-ras over-expression. Transfection with the K-ras siRNA into the C0S7 cells significantly reduced the protein levels of p-ERKl/2, p-Stat3 and girdin. In the color-ectal carcinoma tissues （7 cases） , 5 cases had higher expression of K-ras and girdin compared with pericarcinous tissues. CONCLUSION K-ras regulates girdin expression through the signal pathway of K-ras-ERK1/2-Stat3-girdin.