结直肠癌患者KRAS和BRAF基因突变检测及其临床意义  

Detection of KRAS and BRAF genes mutation and their clinical significance in colorectal adenocarcinomain colorectal cancer

作　　者：凌云[1] 胡海燕[2] 邱田[1] 郭蕾[1] 李文斌[1] 董林[1] 应建明[1] 

机构地区：[1]中国医学科学院肿瘤医院病理科,北京100021 [2]齐齐哈尔医学院第一附属医院,齐齐哈尔161041

出　　处：《中国肿瘤临床与康复》2016年第6期645-649,共5页Chinese Journal of Clinical Oncology and Rehabilitation

摘　　要：目的探讨结直肠癌患者组织中KRAS和BRAF基因突变情况,分析突变与临床病理特征的关系。方法应用荧光PCR-优化寡核苷酸探针法检测304例结直肠癌石蜡包埋标本中KRAS基因2号外显子的12和13密码子、BRAF基因的15号外显子的突变情况,分析KRAS和BRAF基因突变与临床病理特征的关系。结果 KRAS和BRAF基因在结直肠癌的突变率分别为38.8%(118/304)和4.3%(13/304)。KRAS基因突变阳性标本中12密码子的突变率为78.0%,其中p.G12D发生率最高,占总突变的45.3%;13密码子的突变率为22.0%。高年龄组(≥60岁)患者的KRAS基因突变率为47.2%(58/123),高于低年龄组(<60岁)的33.1%(60/181),差异有统计学意义(P<0.05)。转移性结直肠癌患者19例,其KRAS基因突变率为36.8%(7/19),与285例原发性结直肠癌患者的突变率(38.9%,111/285)差异无统计学意义(P>0.05)。BRAF基因在结肠、低分化、黏液腺癌患者中的突变率明显高于直肠、中或高分化和管状腺癌的患者。结论结直肠癌患者中KRAS基因突变的发生率较高,与年龄相关,而与性别、部位、病理类型和分化程度不相关。BRAF基因突变与肿瘤部位、病理类型和分化程度有关。原发性与转移性结直肠癌患者KRAS基因突变率无明显差异。Objective To investigate the frequency of KRAS and BRAF gene mutation and the relationship between the mutations of KRAS and BRAF genes and clinicopathological characteristics in colorectal cancer. Methods Clinical samples from 304 colorectal cancer patients were obtained for KRAS and BRAF gene mutation analysis. All samples were processed from paraffin embedded blocks and microdissection was performed to enrich tumor cells if necessary. Real Time PCR-optimized oligonucleotide probe method was used to investigate codon 12 and 13 in exon 2 of KRAS gene and exon 15 of BRAF gene and to correlate between clinicopathological characteristics and the presence of KRAS and BRAF mutations. Results Activating mutations were detected in 38. 8%（ KRAS） and 4. 3%（ BRAF）. For positive samples of the KRAS gene mutation,78. 0% of the mutations occur in codon 12,with p. G12 D being the most common variant; 22. 0% occur in codon 13 with 38 G 〉A（ G13D）. 0. 4%）. KRAS mutation rate was higher in pations with high age（ 47. 2%,58 /123） than ones with low age（ 33. 1%,60 /181）（ P〈 0. 05）. BRAF mutation rate was higher in tumors of colon,high grade,and mucinous histology. Conclusions The freqency of KRAS mutation is higher in colorectal cancer. KRAS mutation rate was related to age and not related to another clinicopathological characteristics. There was no significant difference in KRAS mutation between the primary and metastatic tumors. BRAF mutation rate was correlation with location,differentiation grades and histological types.

关 键 词：结直肠肿瘤 KRAS基因 BRAF基因 突变 荧光PCR-优化寡核苷酸探针法 

分 类 号：R735.34[医药卫生—肿瘤]