结直肠癌组织中K-ras基因突变情况及其临床意义

K-ras gene mutations in colorectal carcinoma and its clinical significance

目的观察K-ras基因在结直肠癌组织中的突变情况,为临床开展结直肠癌个体化治疗提供依据。方法收集156份结直肠癌组织手术标本作为观察组,20份正常肠黏膜标本作为对照组。提取组织DNA,采用实时荧光定量PCR法检测K-ras基因突变情况。分析K-ras基因突变率及第12、13位密码子突变与结直肠癌患者临床病理特征的关系。结果对照组未检测出K-ras基因突变,观察组K-ras基因突变率为40.4%(63/156),两组基因突变率比较,P<0.05。K-ras基因突变率与结直肠癌患者性别、肿瘤部位、分化程度、病理分期、淋巴结转移及远处转移无关(P均>0.05),与年龄有关(P<0.05)。观察组K-ras基因第12、13位密码子突变率分别为76.2%(48/63)和27.0%(17/63),二者比较P<0.05。观察组K-ras基因第12、13位密码子突变与结直肠癌患者肿瘤分化程度相关(P<0.05),与性别、年龄、肿瘤部位、病理分期、淋巴结转移及远处转移无关(P均>0.05)。结论结直肠癌组织中K-ras基因突变率为40.4%,第12位密码子(GGT^GAT)突变是最常见类型。检测K-ras基因突变情况有助于指导临床开展结直肠癌个体化治疗。

Objective To observe the K-ras gene mutations in the colorectal carcinoma tissues and to provide basis for the individualized treatment of colorectal cancer in clinical. Methods A total of 156 cases of colorectal carcinoma samples( observation group) and 20 cases of normal tissue samples( the control group) were collected. Genomic DNA was extracted and K-ras gene mutations were analyzed by real-time fluorescence quantitative polymerase chain reaction. Then,we analyzed the K-ras gene mutation rate. Meanwhile,the 12 th and 13 th codon mutations in colorectal cancer and the relationships with clinicopathologic features were analyzed. Results The K-ras gene mutations were not found in the control group,and K-ras gene mutation rate in the observation group was 40. 4%( 63 /156). Significant difference was found in the mutation rate between these two groups( P < 0. 05). The K-ras gene mutation rate was not related with sex,tumor location,tumor grade,pathological stage,lymph node and lymph node metastasis( all P > 0. 05),but was related with age( P< 0. 05). The mutation rate at codon 12 and codon 13 of K-ras gene was 76. 2%( 48 /63) and 27. 0%( 17 /63),respectively in the observation group,and significant difference was found( P < 0. 05). The mutation at codon 12 and codon 13 of K-ras gene was related with tumor differentiated degree( P < 0. 05),but not related with sex,age,tumor location,pathological stage,lymph node and lymph node metastasis( all P > 0. 05). Conclusions K-ras gene mutation rate in the colorectal carcinoma tissues is 40. 4%,and the most common type is the codon 12( GGT-GAT) mutation. The detection of Kras gene mutation helps to provide basis for the individualized treatment of colorectal cancer in clinical.