Oncolytic viral therapy for human prostate cancer by conditionally replicating herpes simplex virus 1 vector G207.

Abstract

Over the last few years, a conditionally replicating herpes simplex virus 1 (HSV‐1) vector, G207 has been used for the treatment of several malignant tumors. In this article we evaluate the antitumoral effect of G207 against prostate cancer in vitro and in vivo. The susceptibility of the human prostate cancer cell lines, DU145 and PC3 to G207 at a multiplicity of infection (MOI) of 0.1 was examined. In addition, the growth characteristics of G207 were assessed. Athymic mice with s.c. tumors were inoculated in vivo intraneoplastically with 1x107 plaque‐forming units (PFU) of G207. For the pathological analyses, s.c. tumors were stained with X‐gal. DU145 and PC3 were efficiently destroyed by G207 within 7 days. The viral yields of G207 increased time‐dependently. In vivo, the intraneoplastic inoculation of G207 induced a significant inhibition of the tumor growth. The mean tumor growth ratio was significantly inhibited in the G207‐treated tumors (DU145, P< 0.0001; PC3, P < 0.001 versus controls). In a pathological study, many lacZ‐positive cells were diffusely present in the G207‐treated tumors. G207 showed a significant antitumoral effect against human prostate cancer cell lines, and thus may be considered a useful agent for the treatment of prostate cancer.