s-allylcysteine and Prostatic-Neoplasms

To increase the use of phytochemical supplements as chemoprevention or adjuvant drugs in cancer treatment, it is necessary to verify their biological effects and correlative mechanisms. Recently, S-allylcysteine (SAC) was identified as a potent compound derived from garlic. The aim of this study was to evaluate the anticancer effects of SAC on androgen-independent human prostate cancer (PC-3) cells and to elucidate the possible mechanisms. PC-3 cells were incubated with SAC at three different concentrations. Cell growth was determined by Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine assay. Cell cycle and apoptosis were determined by flow cytometric assay. The expression of apoptosis-related molecules was detected by Western blot analysis. We found that SAC suppressed the proliferation of PC-3 cells and led to cell cycle arrest at the G0/G1 phases, as well as inducing cell apoptosis which was accompanied by the decreased expression of Bcl-2 and increased expression of Bax and caspase 8. This study demonstrated the chemopreventive activity of SAC in vitro, and that SAC may be a promising candidate for prostate cancer treatment.

Topics: Androgens; Antineoplastic Agents; Apoptosis; bcl-2-Associated X Protein; Caspase 8; Cell Cycle Checkpoints; Cell Line, Tumor; Cysteine; Garlic; Humans; Male; Prostatic Neoplasms; Proto-Oncogene Proteins c-bcl-2

To evaluate the effect of S-allylcysteine (SAC) on CWR22R, a human androgen-independent (AI) prostate cancer xenograft, in nude mice. Despite extensive research worldwide there is no effective way to control the growth of prostate cancer, and we previously reported that SAC and S-allylmercaptocysteine (SAMC), two water-soluble derivatives of garlic, inhibit cancer cell invasion through restoration of E-cadherin expression in vitro.. The effects of SAC on tumour cell proliferation markers such as Ki-67 and proliferating cell nuclear antigen, and apoptotic regulators including Bcl-2 and cleaved caspase-3, were assessed by immunohistochemical staining. The inhibitory effects of SAC on prostate cancer invasion was examined by immunoreactivity of E-cadherin and its binding proteins alpha, beta and gamma-catenins. The serum prostate-specific antigen (PSA) level at three different times (initiation, middle and end of treatment) and toxicity of SAC on several organs after treatment were assessed.. Treatment with SAC resulted in inhibition of the growth of CWR22R, with no detectable toxic effect on nude mice. The SAC-induced growth reduction was correlated with a concurrent reduction in serum PSA level and proliferation rate of xenografts, together with an inhibition of invasion through the restoration of E-cadherin and gamma-catenin expression. Furthermore, the apoptotic rate of SAC-treated tumours increased together with a decrease in Bcl-2 and increase in cleaved caspase-3.. These results suggest that this garlic-derived compound might be a potential therapeutic agent for suppressing AI prostate cancer.

Topics: Androgens; Animals; Antineoplastic Agents; Cysteine; Drug Screening Assays, Antitumor; Male; Mice; Mice, Nude; Neoplasms, Hormone-Dependent; Prostate-Specific Antigen; Prostatic Neoplasms; Transplantation, Heterologous; Treatment Outcome