Apple polyphenol decelerates bladder cancer growth involving apoptosis and cell cycle arrest in N-butyl-N-(4-hydroxybutyl) nitrosamine-induced experimental animal model

Apple polyphenol (AP) was found to possess the potential to prevent cancers. Previously, our study showed AP can trigger bladder transitional carcinoma cells to apoptosis and regulate its cell cycle. This study is aimed to evaluate the anticancer effect of AP in urinary bladder carcinoma in vivo. A rat model of bladder cancer was induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (OH-BBN). Tumours were analyzed with immunohistochemical analysis and immunoblot assay. The results showed urinary bladder cancer was established after the administration of OH-BBN. AP can decrease the tumour progression under the monitor of bladder sonography. Analysis of tumour specimens from AP-treated rats showed significant decrease in the expression of Bcl2, cyclin B1, and PCNA, and increase in the expression of p-Chk2 (Thr-68), Bax, and Cip1/p21. The experimental evidences revealed that AP can modulate apoptosis accompanying with cell cycle in animal model of bladder cancer as well as in in vitro system.