The In Vitro Anti-Cancer Activities and Mechanisms of Action of 9-Methoxycanthin-6-one from Eurycoma longifolia in Selected Cancer Cell Lines.

An alkaloid compound from the hairy root culture of Eurycoma longifolia has been isolated and characterised as 9-methoxycanthin-6-one. The aims of these studies were to investigate the in vitro anti-cancer activities of 9-methoxycanthin-6-one against ovarian cancer (A2780, SKOV-3), breast cancer (MCF-7), colorectal cancer (HT29), skin cancer (A375) and cervical cancer (HeLa) cell lines by using a Sulphorhodamine B assay, and to evaluate the mechanisms of action of 9-methoxycanthin-6-one via the Hoechst 33342 assay and proteomics approach. The results had shown that 9-methoxycanthin-6-one gave IC50 values of 4.04 ± 0.36 µM, 5.80 ± 0.40 µM, 15.09 ± 0.99 µM, 3.79 ± 0.069 µM, 5.71 ± 0.20 µM and 4.30 ± 0.27 µM when tested in A2780, SKOV-3, MCF-7, HT-29, A375 and HeLa cell lines, respectively. It was found that 9-methoxycanthin-6-one induced apoptosis in a concentration dependent manner when analysed via the Hoechst 33342 assay. 9-methoxycanthine-6-one were found to affect the expressions of apoptotic-related proteins, that were proteins pyruvate kinase (PKM), annexin A2 (ANXA2), galectin 3 (LGAL3), heterogeneous nuclear ribonucleoprotein A1 (HNRNP1A1), peroxiredoxin 3 (PRDX3), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from the differential analysis of 2-DE profiles between treated and non-treated 9-methoxycanthine-6-one. Proteins such as acetyl-CoA acyltransferase 2 (ACAA2), aldehyde dehydrogenase 1 (ALDH1A1), capping protein (CAPG), eukaryotic translation elongation factor 1 (EEF1A1), malate dehydrogenase 2 (MDH2), purine nucleoside phosphorylase (PNP), and triosephosphate isomerase 1 (TPI1) were also identified to be associated with A2780 cell death induced by 9-methoxycanthine-6-one. These findings may provide a new insight on the mechanisms of action of 9-methoxycanthin-6-one in exerting its anti-cancer effects in vitro.

Mechanisms of action of 17ßH-neriifolin on its anticancer effect in SKOV-3 ovarian cancer cell line.

AIM: Abnormalities in apoptotic signalling pathways often occur in cancer cells and limit the successful chemotherapy outcomes in cancers. Therefore, there is an urgent need to discover new anticancer agents with novel mechanisms of action to overcome the resistance effect in chemotherapy. MATERIALS AND METHODS: In the present study, the anticancer effects and the mechanisms of action of 17ßH-neriifolin (cardiac glycoside) were evaluated by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay and a proteomic approach in treated and non-treated SKOV-3 ovarian cancer cells. RESULTS: 17ßH-neriifolin was found to be active with IC50 values of 0.01 ± 0.001 in SKOV-3 ovarian cancer cell line, as evaluated by the sulforhodamine B (SRB) assay. RESULTS from TUNEL assay indicated that 17ßH-neriifolin caused apoptosis in SKOV-3 cells in a dose-dependent manner. Based on differential analysis of treated and non-treated SKOV-3 two-dimensional electrophoresis (2-DE) profiles, four proteins, namely vimentin (VIM), pyruvate kinase, muscle (PKM), heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) and transgelin (TAGLN1) were identified to be involved in apoptosis. Other proteins including piggybac transposable element derived 5 (PGBD5), DENN/MADD domain containing 2D (DENND2D) and formin-like 1(FMNL) have also been identified to be associated in SKOV-3 cell death induced by 17ßH-neriifolin. CONCLUSION: These findings may provide new insights on the potential of 17ßH-neriifolin's mechanism of action in killing ovarian cancer cells.