Decreased TGFBR1 signaling and breast cancer.

Abstract

1548 Background: We previously identified TGFBR1*6A (rs11466445), a hypomorphic TGF-beta type 1 receptor variant that is associated with cancer risk, has impaired TGF-beta signaling capability, and enhances the migration and invasion of breast cancer cells (Cancer Res 2008, 68:1319). Two recent large meta-analyses of case control studies have found a significant association between TGFBR1*6A and risk of breast cancer (Mol Biol Rep 2010 37:3227; PLoS One 2012,7(8). Rs7034462 is a single nucleotide polymorphism (SNP) in a noncoding region more than 9 kilobases upstream of TGFBR1 exon 1, which has been shown to be associated with decreased TGFBR1 expression similar to TGFBR1*6A (J Exp Clin Cancer Res 2010, 29:57). In this study we tested the hypothesis that rs7034462 may be associated with breast cancer risk. Methods: rs7034462 was genotyped in DNA obtained from patients with breast cancer and their unaffected sisters recruited by the Breast Cancer Family Registry (B-CFR). Results: The median age of cases and controls was 48.8 and 47.6 years, respectively. Using a simple case-control genetic association analysis for this family-matched population, rs7034462 was found to be associated with breast cancer risk. Conclusions: TGFBR1 rs7034462 is emerging as a low penetrance breast cancer susceptibility allele suggesting that two distinct TGFBR1 SNPs, each associated with decreased TGFBR1 expression, may modulate breast cancer risk. [Table: see text]