Genetic variation in SIPA1 in relation to breast cancer risk and survival after breast cancer diagnosis

Abstract
Genetic variation in SIPA1 , signal‐induced proliferation‐associated gene 1 , has been proposed to be associated with aggressive breast tumor characteristics related to metastasis and worse prognosis in humans and rodents. To test this hypothesis, we genotyped 3 single nucleotide polymorphisms (SNP) located at −3092 (AT, rs3741378), and exon 14 + 14 (C>T, rs746429), and examined them in relation to breast cancer risk and overall survival, stratified by tumor characteristics in 2 independent case–control studies conducted in Poland (1,995 cases, 2,296 controls) and in Britain (2,142 cases, 2,257 controls). Vital status (n = 396 deaths) was available for 911 Polish and 1,919 British breast cancer cases with an average follow‐up time of 5.5 years. Overall, we found no significant associations between genetic variants of SIPA1 SNPs and breast cancer risk (per allele odds ratios, 95% confidence intervals (CI): rs931127–0.99, 0.93–1.06; rs3741378–1.03, 0.94–1.13; and, rs74642–0.98, 0.92–1.04). In both studies, SIPA1 polymorphisms were not related to overall mortality (per allele hazard ratios, 95% CI: 1.02, 0.88–1.17; 0.90, 0.72–1.11; 1.04, 0.90–1.21, respectively). Our results do not support a relationship between SIPA1 polymorphisms and breast cancer risk or subsequent survival. Published 2008 Wiley‐Liss, Inc.