PO-049 Quantitative proteomics unveils key mitotic regulators involved in the transition to androgen independent prostate cancer

Abstract

IntroductionMarine invertebrate organisms have received great attention from the scientific community due to its richness in new bioactive compounds with potential anti-proliferative and anticancer activities. In the present study, the cytotoxic efficacy of four marine invertebrate-extracts against human adenocarcinoma colon cancer cells was investigated.Material and methodsHT29, SW480 and HGUE-C-1 human colon adenocarcinoma cell lines were cultured and exposed to 4 marine invertebrate extracts at different concentrations for 24 hour. The anti-proliferative properties were examined by MTT assay. Analysis of apoptosis and cell cycle stages were performed with the Muse Cell Analyzer (Millipore, Hayward, CA, USA). Mitochondrial functionality was determined by the ratio of MitoTracker Red CMXRos and MitoTracker Green FM fluorescent probes (Molecular Probes). Measurement of lactate dehydrogenase (LDH) was performance by a colorimetric assay (Roche Diagnostic, Germany).Results and discussionsThe four marine invertebrate extracts exhibited pronounced cytotoxic effects in the three cancer cell lines used. In this study, CR, PS, NA and NB extracts were able to modify the cell cycle of HGUE-C-1, HT-29 and SW-480 cells, by increasing cell population in the subG1 and G2/M phase in a dose-dependent manner. Results confirmed that NA, NB and CR extracts induced an increase in the percentage of cell population in early apoptosis by Annexin V staining. PS extract on the contrary, raised the late apoptotic population at different concentrations. Mitochondrial membrane depolarization rate, as indicator of apoptosis, was induced significantly by CR, NA and NB extracts in the three cell models used. In contrast PS reduced this parameter in a dose-dependent manner.Finally, the release of the enzyme lactate dehydrogenase (LDH) confirmed a cell death by a necrotic pathway for PS extract.ConclusionOur results strongly suggest that NB, NA and CR extracts exhibit antiproliferative and pro-apoptotic properties in colon cancer cell lines concomitantly to a decreased mitochondrial membrane potential. In contrast, PS extract shows an antiproliferative effect mediated by necrosis in the same cell models. This preliminary study suggests that these extracts present pharmacological potential. Further investigations to determine the responsible compounds and the underlying mechanism are currently ongoing.