CYP1B1 gene polymorphisms correlate with an increased risk of urinary bladder cancer in India

Purpose: The urinary bladder is the target of several toxic compounds, which makes the bladder more prone to cancer. Cytochrome P450 1B1 enzyme is present in tumor tissues and metabolizes the polyaromatic carcinogens and activates several procarcinogens that cause DNA damage. We examined the functional single-nucleotide polymorphisms in the CYP1B1 gene to study their association with the urinary bladder cancer.

Methods: We recruited 234 cases of pure urothelial and 258 bladder cancer-free control samples from the individuals visiting the clinic for various investigations. We genotyped 4 CYP1B1 single-nucleotide polymorphisms using the polymerase chain reaction-restriction fragment length polymorphism analysis. The genotype data were analyzed by the Chi-square test. Haplotypes were constructed to evaluate the joint effect of the 4 polymorphisms.

Results: Overall, 3 polymorphisms-rs10012, rs150799650, and rs1056827 (odds ratio [OR] = 2.34, CI: 1.59-3.45, P<0.0001; OR = 2.59, CI: 1.78-3.77, P<0.0001; OR = 2.32, CI: 1.57-3.44, P<0.0001, respectively) were found to correlate with urinary bladder cancer. Haplotype analysis suggested GTTC, GTTG, and ATGC to be the risk factors for bladder cancer.

Conclusions: Overall, 3 polymorphisms, rs10012, rs1056827, and rs150799650 in the CYP1B1 gene correlate with urinary bladder cancer significantly in the Indo-European population of Uttar Pradesh, India. Further investigations in other populations are advised.