Protein kinase D inhibitor CRT0066101 suppresses bladder cancer growth in vitro and in vivo through induction of cell cycle arrest at the G2-M phase.

e16024Background: Protein Kinase D (PKD) is implicated in tumor growth, death, invasion, and progression. CRT0066101 is an inhibitor of PKD and has antitumor activity in several types of carcinomas. However, the effect and mechanism of CRT0066101 in bladder cancer remain unknown. Methods: The MTS assay was used to evaluate the ability of CRT0066101 to inhibit cellular proliferation in bladder cancer cells. Cell cycle was analyzed by flow cytometry. Protein expression and phosphorylation were assessed by western blotting. Results: We showed that CRT0066101 suppressed the proliferation and migration of 4 bladder cancer cell lines in vitro. We also demonstrated that CRT0066101 inhibited tumor growth in an in vivo mouse model of bladder cancer. To verify the role of PKD in bladder tumor, we found that PKD2 was highly expressed in 8 bladder cancer lines and that RNA interference-mediated silencing of the PKD2 gene dramatically reduced bladder cancer growth in vitro and in vivo, suggesting that the effect of th...