p63 gene expression study and early bladder carcinogenesis.

OBJECTIVES

Urothelial carcinoma is a frequent and aggressive cancer. To gain better insight into the early molecular mechanisms of bladder carcinogenesis, this study analyzed the expression levels of four selected genes (uroplakin II, TATA-BOX-binding protein (TBP/RNA) control gene (NM_00394), and the two main isoforms TATp63 and deltaNp63 of p63).

METHODS

We used real-time quantitative reverse transcriptase-polymerase chain reaction in dissected tissues from normal bladder, noninvasive cancer, and muscle-invasive bladder carcinoma (n = 49). The gene expression levels were compared at different stages of bladder cancer. To confirm the results on protein levels, we used immunohistochemistry on tissue microarrays of the same samples.

RESULTS

The expression of the p63 gene studied was significantly deregulated, with decreasing levels in early cancer versus normal tissue. Immunohistochemistry, performed on the same samples, using p63 antibody, confirmed the results of reverse transcriptase-polymerase chain reaction.

CONCLUSIONS

The results of this study highlight that among the genes strongly deregulated in urothelial carcinoma, p63 is already abnormally expressed in the early stages.