Inverse relationship between the length of the EGFR CA repeat polymorphism in lung carcinoma and protein expression of EGFR in the carcinoma.
OBJECTIVE
There is a CA dinucleotide repeat polymorphism in the first intron of the epidermal growth factor receptor (EGFR) gene. Our aim was to examine the relationship between the CA repeat length in lung carcinoma and EGFR mutation, EGFR gene copy number, and EGFR protein expression level in the carcinoma.


METHODS
We examined 168 lung carcinomas for the length of the CA repeat polymorphism by PCR-polyacrylamide gel electrophoresis analysis, for EGFR mutations by sequencing analysis, for EGFR gene copy number by fluorescence in situ hybridization analysis, and for EGFR protein expression by immunohistochemical analysis.


RESULTS
When the carcinomas were divided into two groups according to the length of their CA repeat polymorphism, the EGFR protein expression level was found to be significantly higher in the shorter allele group than in the longer allele group (P = 0.0116), but its length was not associated with EGFR somatic mutations, high EGFR gene copy numbers, or clinicopathological factors, such as histological type or stage.


CONCLUSIONS
The results suggested that the length of the EGFR CA repeat polymorphism in lung carcinoma is inversely related with level of EGFR protein expression in the carcinoma.
Suzuki
Masaya
M
1st Department of Pathology, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan.
Kageyama
Shinji
S
Shinmura
Kazuya
K
Okudela
Koji
K
Bunai
Tomoyasu
T
Nagura
Kiyoko
K
Igarashi
Hisaki
H
Kiyose
Shinichiro
S
Mori
Hiroki
H
Tao
Hong
H
Goto
Masanori
M
Takamochi
Kazuya
K
Mochizuki
Takahiro
T
Suzuki
Kazuya
K
Ohashi
Riuko
R
Ogawa
Hiroshi
H
Yamada
Takeshi
T
Niwa
Hiroshi
H
Tsuneyoshi
Toshihiro
T
Sugimura
Haruhiko
H
D000368:Aged; D002277:Carcinoma / Q000235:genetics*; D004252:DNA Mutational Analysis; D018900:Dinucleotide Repeats; D066246:ErbB Receptors / Q000235:genetics* / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007438:Introns / Q000235:genetics; D008175:Lung Neoplasms / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011110:Polymorphism, Genetic
D066246:ErbB Receptors