Relationship between EGFR and KRAS mutations and clinicopathologic features of non-small cell lung cancers
10.13315/j.cnki.cjcep.2015.05.013
- VernacularTitle:非小细胞肺癌中EGFR和KRAS基因突变的特点及与临床病理特征的关系
- Author:
Yun LING
;
Tian QIU
;
Zhuo LI
;
Lei GUO
;
Jianming YING
- Publication Type:Journal Article
- Keywords:
lung neoplasm;
non-small cell lung cancer;
EGFR;
KRAS;
mutation;
DNA sequencing
- From:
Chinese Journal of Clinical and Experimental Pathology
2015;(5):536-541
- CountryChina
- Language:Chinese
-
Abstract:
Purpose To explore the relationship between the mutations of epidermal growth factor receptor ( EGFR) and KRAS genes and clinicopathological characteristics in patients with non-small cell lung cancers (NSCLC). Methods Clinical samples from 431 NSCLC patients were obtained for EGFR and KRAS gene analysis. PCR based direct DNA sequencing was used to investigate mutations in exon 18-21 of EGFR gene and codon 12 and 13 of exon 2 of KRAS gene. Results The overall EGFR mutation rate of primary NSCLC was 53. 6% (231/431) in this study cohort and eight cases showed double EGFR mutations. Mutation rates in female and male were 65. 2% (122/187) and 46. 9% (98/209), respectively. The mutation rate was higher in patients with non-smokers and adeno-carcinoma and adenosquamous carcinoma subtypes than in their counterparts (P<0. 05), with the percentage of 57. 2% (124/216), 60. 3% (199/330), 42. 9% (6/14), respectively. In squamous cell carcinomas and other subtypes, EGFR mutation rates were 11. 6% (5/43) and 11. 1% (1/9), respectively. The EGFR mutation types included exon 18 point mutations (4. 0%, 9/227), exon 19 deletion mutations (4. 5%, 101/227), exon 20 insert or point mutations (9. 7%, 22/227) and exon 21 point mutations (41. 4%, 94/227). Activating mutations of KRAS gene were detected in 7. 8%(31/396) of NSCLC. Twenty-eight patients showed codon 12 mutations ( G>T, G>A, G>C) , and three patients had codon 13 mutations ( G>A, G>T) . Most of these mutations were G to T transversion (64. 5%, 20/31). Conclusion Polymerase chain reaction-direct sequencing is a reliable and effective method for the detection of the EGFR and KRAS gene mutation in NSCLC patients. The mutation rate of EGFR is higher in Chinese patients, especial-ly in non-smoking female patients with adenocarcinoma.
