CTLA4 genetic variants associated with urothelial bladder cancer susceptibility

The study evaluated the relationship between the CTLA4 rs231775 (+49A>G) and rs231779 (+1822C>T) variants and susceptibility, stage, prognosis and response to treatment of the urothelial bladder cancer (UBC).

A total of 140 patients with UBC and 145 controls were enrolled. The patients were stratified as non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MICB), metastasis, recurrence, low/moderate/high/very high risk. Demographic, anthropometric, epidemiological, and clinical data were obtained from all individuals using a structured questionnaire. The CTLA4 variants were determined using real-time polymerase chain reaction (qPCR) and the genotypes were tested in the allelic, codominant, dominant, recessive, and overdominant genetic models.

The UBC patients were older and mostly smokers (P < 0.001), with greater waist circumference, systolic, and diastolic arterial pressure (P = 0.005, P = 0.006, and P < 0.001, respectively) than controls. A protective effect for the UBC was observed among the patients carrying the heterozygote genotypes of the CTLA4 rs231775 [odds ratio (OR = 0.40; 95% confidence interval (CI): 0.160.98, P = 0.045) and rs231779 (OR = 0.35; 95% CI: 0.14-0.87, P = 0.024). R² Nagelkerke analysis demonstrated that a model with age and smoking added to the CTLA4 rs231775 SNVs explained 77.0% of the susceptibility to UBC and a model with age and smoking added to the CLTA4 rs231779 explained 77.2% of the susceptibility to UBC.

The CTLA4 rs231775 AG and rs231779 CT heterozygous genotypes in the overdominant model together with age and smoking may be useful as potential biomarkers for the UBC susceptibility.