Investigation of HER-2 codon 655 single nucleotide polymorphism frequency and c-ErbB-2 protein expression alterations in gastric cancer patients.
OBJECTIVE
To investigate both whether the risk of gastric cancer is associated with the Ile/Val single nucleotide polymorphism (SNP) of human epidermal growth factor receptor-2 (HER-2) transmembrane domain-coding region at codon 655 and the suggested existence of HER-2 expression in gastric cancer cases in a Turkish patient group.


METHODS
Polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) strategy was used to analyze the presence of HER-2 SNP at codon 655. c-erbB-2 expression pattern was analyzed by immunohistochemistry. The results were compared between gastric carcinoma group and chronic gastritis group, as well as between clinicopathological parameters and carcinoma.


RESULTS
Results showed that Ile/Val genotype accounted for 20% within the Turkish gastric carcinoma group, and none in chronic gastritis group, and this genotyping was associated with stage IV gastric cancers (P=0.04). Positive membranous HER-2 immunoreactivity, on the other hand, accounted for 24% within the Turkish gastric carcinoma group and none from chronic gastritis cases; further, it was correlated with intestinal type carcinomas (P=0.007), and stage III-IV carcinomas (P=0.004).


CONCLUSIONS
These observations imply that the tested HER-2 SNP may participate in the development and progression of gastric cancer. Thus, after confirming these results with large sample groups, HER-2 codon 655 SNP and/or c-erbB-2 overexpression may also be used as a poor prognostic indicator for gastric carcinomas.
Satiroglu-Tufan
N-Lale
NL
Pamukkale University School of Medicine, Department of Medical Biology, Center for Genetic Diagnosis, Molecular Genetics Laboratory, Kinikli Kampusu, Morfoloji Binasi, Kat 3, Denizli, Turkey. nltufan@pau.edu.tr
Bir
Ferda
F
Calli-Demirkan
Nese
N
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018196:Carcinoma, Adenosquamous / Q000737:chemistry / Q000235:genetics*; D016022:Case-Control Studies; D003062:Codon / Q000235:genetics*; D005260:Female; D005756:Gastritis / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D018734:Genes, erbB-2 / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011237:Predictive Value of Tests; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis / Q000235:genetics*; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000737:chemistry / Q000235:genetics*; D014421:Turkey
D003062:Codon; D018719:Erb-b2 Receptor Tyrosine Kinases