Toll-like receptors (TLRs) are key players in the innate immune system and initiate the inflammatory response to foreign pathogens such as bacteria, fungi and viruses. The proposed role of chronic inflammation in prostate carcinogenesis has prompted investigation into the association of common genetic variation in TLRs with the risk of this cancer. We investigated the role of common SNPs in a gene cluster encoding the TLR10, TLR6 and TLR1 proteins in prostate cancer etiology among 1,414 cancer cases and 1,414 matched controls from the Cancer Prevention Study II Nutrition Cohort. Twenty-eight SNPs, which included the majority of the common nonsynonymous SNPs in the 54-kb gene region and haplotype-tagging SNPs that defined 5 specific haplotype blocks, were genotyped and their association with prostate cancer risk determined. Two SNPs in TLR10 [I369L (rs11096955) and N241H (rs11096957)] and 4 SNPs in TLR1 [N248S (rs4833095), S26L (rs5743596), rs5743595 and rs5743551] were associated with a statistically significant reduced risk of prostate cancer of 29-38% (for the homozygous variant genotype). The association of these SNPs was similar when the analysis was limited to cases with advanced prostate cancer. Haplotype analysis and linkage disequilibrium findings revealed that the 6 associated SNPs were not independent and represent a single association with reduced prostate cancer risk (OR = 0.55, 95% CI: 0.33, 0.90). Our study suggest that a common haplotype in the TLR10-TLR1-TLR6 gene cluster influences prostate cancer risk and clearly supports the need for further investigation of TLR genes in other populations.
(c) 2008 Wiley-Liss, Inc.