Population study of genetic polymorphisms and superficial bladder cancer risk in Han-Chinese smokers in Shanghai

We investigated the association between the polymorphisms of DNA repair genes, metabolic enzyme genes, and superficial bladder cancer to better understand the role of gene polymorphisms in bladder carcinogenesis for the Han-Chinese population in Shanghai.

The SNPs in the XPC, XPG, XRCC1, NQO2, CYP2C9, CYP2C19, CYP2D6, CYP3A4, and CYP3A5 genes were genotyped using the TaqMan Probe-based polymerase chain reaction.

The AC + CC genotypes of XPC Lys939Gln and the CC genotype of XPG His1104Asp were more frequent in patients of superficial bladder cancer at the initial diagnosis (adjusted OR [95% CI], 1.89 [1.21-3.24]; adjusted OR [95% CI], 1.07 [0.86-1.87], respectively). The risk for carriers of the XPC-33512C allele increased after stratifying by smoking habits (adjusted OR [95% CI], 1.95 [0.56-6.09]). There was a significant trend for an increased carcinogenesis risk with an increasing number of putative high-risk alleles. We found no significant associations between any of the ten polymorphisms and clinicopathological features of superficial bladder cancer.

These results suggest that the polymorphism in XPC Lys939Gln may modulate superficial bladder cancer risk, and these effects may preferentially affect current smokers. The data also support the possibility of an increased risk for superficial bladder cancer in individuals with a higher number of genetic variations in DNA repair and metabolic enzyme genes.