K—ras基因与结直肠癌疗效

K—ras基因是一种癌基因，促进细胞生长、分化，基因的突变使ras蛋白丧失GTP酶活性，导致细胞的异常生长、分化，促进癌的发生，同时导致使用抗表皮生长因子受体（EGFR）多克隆抗体药物治疗的结直肠癌患者无明显获益。结直肠癌不同实体肿瘤的K—ras基因突变率不同，K—ras基因野生型或突变型对治疗方案选择及预后具有重要意义，突变型患者使用抗EGFR抗体治疗效果差，对5-Fu、FOLFOX疗效尚无一致定论。

K-ras gene and colorectal cancer therapeutic effect

K-ras gene is one of oncogenes, which promotes cells growth and differentiation. Ras protein loses the activity of GTP enzyme because of K-ras mutations, and that may cause abnormal growth, differ- entiation of cells and promote the occurrence of tumor. Patients with colorectal carcinoma that carry mutations in K-ras gene do not benefit from the administration of anti-epidermal growth factor receptor （EGFR） polyclonal antibodies. Different solid tumors of colorectal carcinoma have different K-ras mutation rates. Different geno- types of K-ras gene （wild-type or K-ras mutant type） affect significantly on treatment options and prognosis. The efficacy of mutant type patients with anti-EGFR antibodies is poor, and the therapeutic effects of 5-FU and FOLFOX are still unclear.