Two common chromosome 8q24 variants are associated with increased risk for prostate cancer

Two variants (rs1447295/DG8S737) of chromosome 8q24 were recently reported to be associated with increased risk of prostate cancer (PC). To confirm this finding, we genotyped and compared the frequencies of these polymorphisms among 1,121 Caucasian men with PC (435 men with familial PC, 491 men with sporadic PC, and 195 men with aggressive PC) to 545 population-based controls. For the single nucleotide polymorphism marker rs1447295, frequencies of the minor allele (A) were 10.3% in controls, 11.9% in sporadic cases, 16.7% in familial cases, and 17.2% in aggressive cases. Compared with controls, the A allele was significantly more common in both familial PC [odds ratios (OR), 1.93; 95% confidence intervals (95% CI), 1.37-2.72; P = 0.0004] and aggressive PC (OR, 1.87; 95% CI, 1.28-2.74; P = 0.0005) but not for sporadic PC (OR, 1.16; 95% CI, 0.85-1.58; P = 0.25). Although the A allele was more frequent in aggressive PC cases when compared with controls, the allele frequencies were similar among cases with high- and low-grade PC (Gleason grades <7 and ≥7, respectively). For the microsatellite marker DG8S737, the -8 allele was significantly more frequent in familial PC (OR, 1.68; 95% CI, 1.09-2.60; P = 0.031), whereas the -10 allele was more frequent in aggressive PC (OR, 2.85; 95% CI, 1.52-5.36; P = 0.0004). Haplotype analysis showed significant differences in haplotype frequencies between the familial PC (P = 0.006) and aggressive PC (P = 0.005) cases versus controls. The -8/A haplotype showed the strongest association with familial PC (P = 0.008), whereas the -10/A haplotype was most strongly associated with aggressive PC (P = 0.00005). These results further confirm the importance of these two polymorphic variants (rs1447295 and DG8S737) as risk factors for PC. However, the mechanism explaining this increased risk has not yet been established.