Chemoprevention represents a strategy designed to inhibit or reverse the process of
carcinogenesis by administering one or several noncytotoxic chemical compounds. The epidemiology of prostate
carcinoma indicates that this
cancer is a prime candidate for a strategy aimed at prevention due to the extremely high prevalence rate, rising annual incidence, and long latent interval between the
cancer-initiating events and the development of invasive disease. Chemopreventive agents may exert their inhibitory effects at different stages of the multistep carcinogenic process broadly categorized as initiation, promotion, and progression. The synthetic
retinoids,
polyamine synthesis inhibitors, and
antiandrogens are among the compounds shown to have in vitro or in vivo chemopreventive effects in prostate
carcinogenesis. A major limitation in the evaluation of such agents in a human
prostate cancer is the long duration of clinical trials required to assess the efficacy with an endpoint of
cancer development. Premalignant epithelial changes such as prostate intraepithelial
neoplasia, or PIN, are highly associated with
prostate cancer, and share many molecular features of invasive
cancer. If the reversal or inhibition of intraepithelial
neoplasia translates to a concomitant reduction in clinically relevant
prostate cancer, then the pharmacological modulation of PIN may provide a rapid means to evaluate the effects and benefits of potential chemopreventive agents.
CONCLUSION: