Protocadherin 17 promoter methylation in tumour tissue from patients with bladder transitional cell carcinoma

Abstract

Objective To investigate the clinical significance of protocadherin 17 ( PCDH17) promoter methylation in bladder cancer. Methods Methylation-specific polymerase chain reaction was used to examine the promoter methylation status of PCDH17 in tumour tissue specimens obtained from patients with bladder cancer, and in normal bladder epithelial tissue specimens obtained from age- and sex-matched controls. The correlations between methylation status and demographic and clinicopathological parameters, and disease outcome, were assessed. Results Methylation of the PCDH17 promoter was detected in 77/115 (67.0%) patients with bladder cancer and 0/43 (0%) of the controls. Methylation was significantly associated with high cancer grade (G3), advanced cancer stage (T2–T4), large tumour diameter (> 3 cm) and tumour recurrence. Methylation was also associated with significantly shorter survival time compared with unmethylated PCDH17 in patients with bladder cancer, and was an independent predictor of overall survival. Conclusions PCDH17 promoter methylation is closely associated with bladder cancer malignancy and may be used as an independent predictor of clinical outcomes in patients with bladder cancer.