Objective: A functional -94 insertion/deletion polymorphism (rs28362491) in the promoter of the NF-κ B1 gene was reported to influence NF-κ B1 expression and confer susceptibility to different types of cancer. This study aims to determine whether the polymorphism is associated with the risk of urinary cancer, including renal cancer, bladder cancer and prostate cancer.
Methods: TaqMan method was applied to genotype the NF-κ B1 -94 ins/del ATTG promoter polymorphism in three case-control studies: renal cell carcinoma group (1216 cases and 1588 controls), bladder cancer group (730 cases and 780 controls), and prostate cancer group (820 cases and 945 controls). Logistic regression was used to assess the association between the polymorphism and urinary cancer risk.
Results: The del/del genotype was detected to be associated with a statistically significant increased risk of bladder cancer when taking the ins/ins genotypes as reference (P < 0.001, adjusted odds ratio (OR) = 1.32, 95% confidence interval (CI) = 1.14-1.52). Furthermore, in bladder cancer, the same results were observed in the del/del genotype compared with the ins/ins + ins/del genotypes (P < 0.001, OR = 1.82, 95% CI = 1.41-2.35), and the del allele compared with the ins allele (P < 0.001, OR = 1.29, 95% CI = 1.12-1.49). However, no significant difference was observed in the associations between the NF-κ B1 polymorphism and the risk of renal cell carcinoma or prostate cancer in all kinds of models.
Conclusions: In the Chinese population, the -94 ins/del ATTG polymorphism in NF-κ B1 promoter may contribute to the etiology of bladder cancer instead of renal cell carcinoma or prostate cancer.
Keywords: NF-κ B1 gene; bladder cancer; polymorphism; prostate cancer; renal cell carcinoma.