The effects of obesity and HER‐2 polymorphisms as risk factors for endometrial cancer in Korean women

OBJECTIVE: To evaluate the relationship between single nucleotide polymorphisms (SNPs) in the HER-2 gene, body mass index (BMI) and the risk of endometrial cancer. DESIGN: Case-control study. SETTING: Medical centres in Korea. SAMPLE: DNA samples and medical histories were obtained from 125 endometrial cancer cases and 302 controls. METHODS: The genotypes evaluated in HER-2 at positions -423, -655, -776, -857, -1170, -1177, -1253 of the coding region and two SNPs located in an intron by SNP-IT assay using SNPstream Ultra-high throughput system. MAIN OUTCOME MEASURES: Odd ratio for endometrial cancer associated with HER-2 polymorphisms and BMI. RESULTS: Cases had a significantly higher BMI than controls and the obese subjects had a 2.65-fold increased risk for endometrial cancer. However, HER-2 polymorphism was not associated significantly with the risk of endometrial cancer. Subjects with BMI > or = 25 kg/m2 who carried rs1801200 AA, rs1801200 GA/GG, rs1810132 CT/CC, rs2517951 CT/TT and rs1058808 CG/GG genotype had significantly increased risk of endometrial cancer than subjects with a normal BMI (P for linear trend <0.05). However, the risk in the subjects with the variant allele for HER-2 genotypes did not differ significantly compared to those with homozygous wild-type allele within specific BMI subgroups. CONCLUSIONS: Endometrial cancer risk increased significantly in proportion to BMI. However, HER-2 polymorphism did not affect significantly on the risk of endometrial cancer.