An alternative method for screening EGFR mutation using RFLP in non-small cell lung cancer patients.
BACKGROUND
Epidermal growth factor receptor (EGFR) mutations are strong determinants of tumor response to EGFR tyrosine kinase inhibitors in non-small cell lung cancers (NSCLCs). Currently available methods of EGFR mutation detection rely on direct sequencing. Here, we describe the use of an alternative way to screen EGFR mutations.


METHODS
A total of 109 frozen tumor specimens from NSCLC patients were obtained. For mutational analysis of EGFR exons 18, 19, and 21, reverse transcription-polymerase chain reaction was performed on the cDNA using original primers designed for restriction fragment length polymorphism (RFLP).


RESULTS
EGFR mutations were detected in 37 patients (34%) by both RFLP and direct sequencing except one case in which it was detected only by RFLP. EGFR mutations were more frequently observed to be significant by multivariate analysis in patients with adenocarcinoma (OR = 5.56), no-smoking history (OR = 4.34), and 65-year-old or younger (OR = 2.64), but not in women (OR = 1.14). Among 37 patients, 18 were treated with gefitinib and 9 responded to the treatment. One patient without any mutation responded.


CONCLUSIONS
RFLP is a useful method for screening EGFR mutations and can also be applied to predicting the sensitivity of NSCLC patients to EGFR-tyrosine kinase inhibitors.
Kawada
Ichiro
I
Department of Internal Medicine, Hino Municipal Hospital, Hino, Tokyo, Japan.
Soejima
Kenzo
K
Watanabe
Hideo
H
Nakachi
Ichiro
I
Yasuda
Hiroyuki
H
Naoki
Katsuhiko
K
Kawamura
Masafumi
M
Eguchi
Keisuke
K
Kobayashi
Koichi
K
Ishizaka
Akitoshi
A
D000230:Adenocarcinoma / Q000188:drug therapy / Q000235:genetics; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics; D018287:Carcinoma, Large Cell / Q000188:drug therapy / Q000235:genetics; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000235:genetics*; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000235:genetics; D004273:DNA, Neoplasm; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics*; D005260:Female; D000077156:Gefitinib; D005820:Genetic Testing / Q000379:methods*; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D009367:Neoplasm Staging; D012150:Polymorphism, Restriction Fragment Length / Q000235:genetics*; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use; D011799:Quinazolines / Q000627:therapeutic use
D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D066246:ErbB Receptors; D000077156:Gefitinib