Bladder cancer risk associated with genotypic polymorphism of the matrix metalloproteinase-1 and 7 in North Indian population.

Matrix metalloproteinases (MMPs) contribute to tumor invasion and microenvironment, hence are associated with bladder cancer risk. We therefore, tested whether polymorphisms in MMP genes modify the risk of bladder cancer (BC) and whether smoke exposure modifies this risk. Genotyping was performed in 200 BC patients and 200 controls by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). MMP1-1607 2G/2G and MMP7-181 GG genotype were associated with increased risk of BC (p < 0.001; OR, 3.04; 95% CI- 1.71-5.39 and p, 0.005; OR, 2.38; 95% CI- 1.30-4.34) respectively. Smokers in BC patients showed significant increased risk for the same SNPs (p, 0.006; OR, 3.20; 95% CI- 1.40-7.31 and p, 0.009; OR, 2.85; 95% CI- 1.30-6.23 respectively). Haplotype analysis too revealed significant association with G/2G of MMP1-519-1607 (p< 0.001; OR, 2.62; 95% CI- 1.68-4.09). The 2G allele carrier (1G/2G + 2G/2G) of MMP1-1607 showed a protective effect and high recurrence free survival in Bacillus Calmette-Guérin (BCG) treated non muscle invasive BC (NMIBC) patients (log rank p, 0.030). Our data suggested that MMP1-1607 2G and MMP7-181 G allele were associated with high risk of BC, which was quite evident amongst smokers too. BCG treated NMIBC patients reflected protective effect for 2G allele carrier (1G/2G + 2G/2G) of MMP1-1607. This study provided new support for the association of MMP1-1607 and MMP7-181 in bladder cancer development, the tumorigenic effect of which was observed to be more enhanced in case of tobacco exposure.