[Relationship between EGFR and K-ras mutations and clinicopathological characteristics and response to erlotinib treatment in 301 Chinese patients with non-small cell lung cancer].
OBJECTIVE
To investigate gene mutations of epidermal growth factor receptor (EGFR) and K-ras in Chinese patients with non-small cell lung cancer (NSCLC) and its clinicopathological significance, and to analyze the correlation between these mutations and tumor response to erlotinib treatment.


METHODS
Mutations of exons 18, 19, 20 and 21 of the EGFR and codons 12, 13 of the K-ras in 301 cases of NSCLC were detected by PCR-amplification and gene sequencing. The relationship between the mutations and clinicopathological characteristics of the 301 patients was analyzed.


RESULTS
EGFR mutations were present in 32.9% (99/301) of the samples: 3 mutation in exon 18, 59 in exon 19, 2 in exon 20, and 35 in exon 21. Mutations of K-ras were present in 4.7% (14/301) of the samples: 13 in codon 12 and 1 in codon 13. EGFR mutations were never found in tumors with K-ras mutations, suggesting a mutually exclusive relationship. EGFR mutations were more common in adenocarcinomas, non-smokers and females. Seven out of 10 erlotinib-treated patients with disease control carried EGFR mutation.


CONCLUSIONS
The frequency of EGFR mutation in Chinese NSCLC patients is higher than that in Westerners, but the frequency of K-ras mutation is quite opposite. Combined detection of EGFR gene and K-ras gene mutation may help clinicians to choose patients who may gain benefit from EGFR tyrosine kinase inhibitor (EGFR-TKI) treatment, and to predict their response to erlotinib treatment and prognosis.
Tianjin Diagnosis and Therapy Center of Lung Cancer, Department of Pathology, Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin 300060, China.
Lei-na
LN
Sun
Huan-ling
HL
Luan
Feng-lin
FL
Zang
Meng
M
Wang
Na
N
Dong
Yan
Y
Guo
Bao-cun
BC
Sun
Zhong-li
ZL
Zhan
D000230:Adenocarcinoma / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D003062:Codon; D066246:ErbB Receptors / Q000235:genetics*; D000069347:Erlotinib Hydrochloride; D005091:Exons; D005260:Female; D018773:Genes, erbB-1; D011905:Genes, ras; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D011799:Quinazolines / Q000627:therapeutic use*; D012737:Sex Factors; D012907:Smoking; D055815:Young Adult; D018631:ras Proteins / Q000235:genetics*
D003062:Codon; C117307:KRAS protein, human; D047428:Protein Kinase Inhibitors; D011518:Proto-Oncogene Proteins; D011799:Quinazolines; D000069347:Erlotinib Hydrochloride; C512478:EGFR protein, human; D066246:ErbB Receptors; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins