Macrophage migration inhibitory factor gene -173G>C polymorphism and risk of bladder cancer in southeast China: a case-control analysis.

Inflammatory factors may promote carcinogenesis. Macrophage migration inhibitory factor (MIF), which is derived from T-cell, known as a member of the transforming growth factor-β (TGF-β) superfamily, plays an important role in the pro- and anti-inflammatory response to infection and in the etiology of bladder cancer. We hypothesized that MIF-173 locus polymorphism might contribute to genetic susceptibility to bladder cancer. In a hospital-based case-control study of 325 patients with bladder cancer and 345 cancer-free controls frequency-matched by age, sex, smoking status, and alcohol use, we genotyped the MIF polymorphism and analyzed immunohistochemical stained operational bladder cancer tissue sections for MIF. We found that individuals with GC/CC genotype had a significantly decreased risk of bladder cancer (adjusted OR = 0.57, 95% CI, 0.41-0.79) than those with GG genotype. In the stratification analysis, we found that the decreased risk was more pronounced among older subjects (adjusted OR = 0.56, 95% CI, 0.39-0.81), men (0.47, 0.33-0.68), smokers (0.54, 0.35-0.85), and ever-drinkers (0.44, 0.27-0.71). The percentage of positive staining in the cytoplasm and nucleus in the normal and bladder cancer with CC/GC genotype tissues was higher than that of GG genotype bladder cancer tissue(39.1% vs. 75.0% in strong staining for GG and GC/CC genotypes, respectively, P = 0.028). In conclusion, MIF -173G>C polymorphism may play a role in the etiology of bladder cancer in southern Chinese population. Large studies are warranted to validate our findings.