Objective: We hypothesized that variations in the ESR2 gene may influence estrogen exposure in the uterus and thus influence endometrial cancer risk. We validated and screened for variants in the ESR2 gene and examined whether they are associated with endometrial cancer risk.
Methods: We resequenced the promoter and coding regions of the ESR2 gene in 24 endometrial cancer cases, and genotyped the validated/discovered SNPs and intronic dinucleotide CA repeat in a nested case-control study of endometrial cancer (cases = 222, controls = 666) in the Nurses' Health Study (NHS). We also explored statistical interaction between ESR2 genotypes and body mass index (BMI) or hormone replacement therapy (HRT) use among postmenopausal women and cancer risk.
Results: Two SNPs were validated [rs1256049 in exon 5 (allelic frequencies = 98% G, 2% A) and rs1271572 in the promoter region (allelic frequencies = 60% G, 40% T)]. After adjusting for potential confounders, we observed no association between ESR2 gene polymorphisms and endometrial cancer risk [rs1256049 (OR = 1.2; 95%CI: 0.7-2.3), rs1271572 (OR = 0.8; 95%CI: 0.5-1.1) and CA repeat (22 repeat allele versus > or = 22 repeat allele, OR = 1.1; 95%CI: 0.7-1.7)]. We also did not observe any significant effect modification of the ESR2 polymorphisms by BMI or HRT use among postmenopausal women.
Conclusion: Our results indicate that ESR2 polymorphisms may not be associated with endometrial cancer risk.
Copyright 2004 Kluwer Academic Publishers