Potential role of CCND1 G870A genotype as a predictor for urothelial carcinoma susceptibility and muscle-invasiveness in Taiwan

The cell cycle regulator cyclin D1 (CCND1) is thought to play a major role in the transition of cell cycle from G1 to S phase. It is known that a common CCND1 G870A genotype is associated with bladder cancer in Japan and China, but not in the Western World. There is neither a report about its role in Taiwan's population, nor its genetic role of CCND1 G870A in another worldwide urothelial cancer, upper tract urothelial cancer (UTUC). Therefore, we aimed at investigating the role of CCND1 G870A in both bladder cancer and UTUC in Taiwanese cohorts. The CCND1 G870A genotypes of 171 (101 bladder cancer and 70 UTUC) patients and 243 control subjects were determined by PCR-RFLP and their correlation with clinical and histopathological data was evaluated. The genotype analysis results showed that CCND1 GG genotype was associated with a lower risk overall in urothelial (P = 0.008, OR = 0.44, 95% CI = 0.24-0.81) and bladder cancer patients (P = 0.008, OR = 0.34, 95% CI = 0.15-0.76) than those of the AA genotype. In addition, patients carrying the AG genotype had a 0.29-fold lower odds ratio of muscle-invasive cancer procession (95% CI = 0.12-0.70) compared with those carrying the AA genotype in bladder cancer patients. Surprisingly, the GG genotype had a 5.88-fold higher odds ratio of muscle-invasive cancer procession (95% CI = 1.08-32.01) compared with those carrying the AA genotype in UTUC. No association between any CCND1 G870A genotype and higher-grade risk was found. Our results suggest that the G allele of the CCND1 G870A polymorphism may be a potential predictive and prognostic biomarker to distinguish between bladder cancer and UTUC in Taiwan.