The dual impact of coxsackie and adenovirus receptor expression on human prostate cancer gene therapy

In a recent paper, we reported a significant difference in coxsackie and adenovirus receptor (CAR) from several human bladder cancer cell lines that correlated with their sensitivities to adenoviral infection (Y. Li, R-C. Pong, J. M. Bergelson, M, C. Hall, A. I. Sagalowsky, C-P. Tseng, Z. Wang, and J. T. Hsieh, Cancer Res., 59: 325-330, 1999). In human prostate cancer, CAR protein is down-regulated in the highly tumorigenic PC3 cell line, which suggests that, in addition to its function as a viral receptor, CAR may have a pathophysiological role in prostate cancer progression. In this paper, we document that CAR does not merely enhance the viral sensitivity of prostate cancer cells but also acts as a tumor inhibitor for androgen-independent prostate cancer cells. Our data indicate that CAR is a potential therapeutic agent for increasing the efficacy of prostate cancer therapy.