结直肠癌NRAS基因突变检测及其临床意义

Detection of NRAS gene mutation and its clinical significance in metastatic colorectal cancer

目的:探索结直肠癌NRAS基因突变的特征及其临床意义。方法:收集214例江南大学附属医院2014年3月至2015年1月收治的结直肠癌患者术后石蜡包埋组织标本,采用扩增受阻突变体系检测上述标本的NRAS基因第二、三、四外显子的突变情况,结合临床病理参数分析该项检测的意义。结果:214例结直肠癌患者中有8例NRAS基因发生突变,NRAS基因突变率3.74%。第二、三外显子均突变四例,尚未发现第四号外显子的突变。NRAS突变状况在不同的性别、分化程度、组织学类型和淋巴结转移情况中尚未观察到明显差异。结直肠癌患者中NRAS基因的突变状况与其免疫表型ALK、Ki67、CAM5.2、Her-2无明显相关性。结论:结直肠癌NRAS基因的突变较低,主要为第二、三外显子的突变。NRAS基因的突变状况与性别、年龄、分化程度、免疫表型的相关性有待进一步证实。

Objective：To investigate the characteristics and its clinical significance of NRAS gene mutation in metastatic colorectal cancer.Methods：Collect 214 formalin fixed and paraffin embedded tissue of colorectal cancer patients with metastatic from 2014 March to 2015 January in Affiliated Hospital of Jiangnan University.Amplification refractory mutation system（ARMS）was used to detect NRAS gene exons 2-4 mutation and then we analyzed its clinical pathological significance.Results：8 of the 214 cases presented with NRAS gene mutation,and the NRAS gene mutations rate was 3.74%（8/214）,of which exon 2 and exon 3 were both mutated a half（exon 2 mutation,4 cases,exon 3 mutation,4 cases）,exon 4 mutation was not found in this group of patients.There was no significant association found in different gender,differentiation degree,histological type,lymph nod metastasis.The immunophenotype such as ALK,Ki67,Cam5.2,Her-2 didn＇t show any correlation with NRAS mutation.Conclusion：NRAS gene mutation rate is low in metastatic colorectal cancer,and mutations mainly occur in exon 2 and exon 3.We need more evidence to prove that NRAS mutations are correlated with gender,age,differentiation and the status of lymph node metastasis.