Gain of 5p15.33 is associated with progression of bladder cancer

Objective: To search for a biological marker to distinguish low-risk from high-risk bladder cancer indicating disease progression. Methods: The whole genome-wide copy numbers were screened in 18 patients with bladder cancer using array comparative genomic hybridization (CGH) consisting of 4,030 bacterial artificial chromosome clones. Results: Gain of 5p15.33, including TPPP (tubulin polymerization-promoting protein) and ZDHHC11 (zinc finger DHHC domaincontaining protein 11) genes, was detected in 5 of 9 (55.6%) high-grade bladder cancers and no (0%; n = 9) low-grade bladder cancer. To confirm the preliminary data, 5p15.33 gain was studied by fluorescence in situ hybridization (FISH) in 100 patients, and the results were compared with biological characteristics. In FISH analysis, gain of 5p15.33 was significantly correlated with higher histological grade (p < 0.0001) and advanced pathological stage (p = 0.0284). Tumors with a gain of 5p15.33 had a significantly higher progressionfree survival rate than those without (p = 0.0006, log-rank test). Multivariate analysis revealed that gain of 5p15.33 was a predictor for disease progression in bladder cancer (hazard ratio: 1.887, 95% confidence interval: 1.215-2.968,p = 0.0050). Conclusion: These data suggest that gain of 5p15.33 (TPPP and ZDHHC11) may become a potential biomarker identifying high-risk patients with disease progression in bladder cancer. Copyright (c) 2007 S. Karger AG, Basel.