Effects of hyperbaric oxygen therapy on in vivo marine prostate cancer cell PC-3

Objective To assess the effects of hyperbaric oxygen(HBO) on indolent prostate cancer on a murine model. Methods Human prostate cancer cell line PC-3 ceils were injected into 40 severe combined-immunodeficient mice. They were randomized to undergo 20 sessions of either HBO or normobarie air in standardized conditions, and observed for 4 weeks before the histological assess-ment of any palpable tumors developed. The analysis parameters included tumour volume, microvessel density, apoptosis markers (p53, p27) and proliferative index (Ki-67). Results On the 28th day af-ter tumor vaccination, the tumor volume was (425.8±13.9)mm3 in HBO group and (433.6±12.8) mm3 in normobaric air group (P>0.05). Mierovessel density and Ki-67, p53, p27 protein expression were 69.7±9.5, (55. 2±6. 7)%, (31.9±5. 3)%, (80. 4±5. 7)% in HBO group;77. 1±8. 7, (50.6±7.3)%, (30.5±4. 7)%, (85.3±6.4)% in norrnobaric air group, respectively. There were no significant differences in both groups (P>0. 05). Conclusions HBO does not accelerate the growth of indolent prostate cancer in murine model. This result suggests that HBO does not increase the risk of residual prostate cancer reactivation when it is used to manage radiation-induced hemorrhag-ic cystitis in patients treated by pelvic radiotherapy for prostate cancer. Key words: Hyperbaric oxygenation; Prostatic neoplasms; Radiotherapy; Hemorrhagiccystitis