ABSTRACT
BACKGROUND: 17ßH-neriifolin, a cardiac glycoside compound had been successfully isolated from Cerbera odollam leaves based on the bioassay guided-isolation procedure. The aim of these studies were to determine the in vitro anti-cancer and binding effects of 17ßH-neriifolin on Na+, K+-ATPase. METHODS: The in vitro anti-cancer effects were evaluated using Sulphorhodamine B and Hoescht 33342 assays. The Na+, K+-ATPase assay was carried out using Malachite Green assay. In silico molecular docking studies and in vitro malachite green assay were used to predict the binding activities of 17ßH-neriifolin on Na+, K+-ATPase and ouabain was also included as for comparison studies. RESULTS: The compound was tested against breast (MCF-7, T47D), colorectal (HT-29), ovarian (A2780, SKOV-3) and skin (A375) cancer cell lines that gave IC50 values ranged from 0.022 ± 0.0015 to 0.030 ± 0.0018 µM. The mechanism of cell death of 17ßH-neriifolin was further evaluated using Hoescht 33342 assay and it was found that the compound killed the cancer cells via apoptosis. 17ßHneriifolin and ouabain both bound at α-subunit in Na+, K+-ATPase and their binding energy were - 8.16 ± 0.74 kcal/mol and -8.18 ± 0.48 kcal/mol respectively. CONCLUSION: The results had confirmed the anti-proliferative effects exerted by 17ßH-neriifolin in the breast, colorectal, ovarian and skin cancer cell lines. 17ßH-neriifolin had shown to cause apoptotic cell death in the respective cancer cell lines.17ßH-neriifolin and ouabain both bound at α-subunit in Na+, K+-ATPase and their binding energy were -8.16 ± 0.74 kcal/mol and -8.18 ± 0.48 kcal/mol respectively. This is the first report to reveal that 17ßH-neriifolin managed to bind to the pocket of α-subunit of Na+.K+-ATPase.
Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/metabolism , Cardenolides/pharmacology , Colorectal Neoplasms/metabolism , Ovarian Neoplasms/metabolism , Sodium-Potassium-Exchanging ATPase/metabolism , Apocynaceae , Apoptosis/drug effects , Breast Neoplasms/drug therapy , Cell Line, Tumor , Cell Proliferation/drug effects , Colorectal Neoplasms/drug therapy , Female , Humans , Molecular Docking Simulation , Ovarian Neoplasms/drug therapyABSTRACT
Andrographolide (Andro) is a diterpenoid that is isolated from Andrographis paniculata and reported to be active against several cancer cell lines. However, few in-depth studies have been carried out on its effects on ovarian cancer cell lines alone or in combination with cisplatin (Cis), which is commonly used to treat ovarian cancer. The aim of this study was to determine the anti-proliferative and apoptotic effects of Andro administered alone and in combination with Cis in the ovarian A2780 and A2780(cisR) cancer cell lines using five different sequences of administration (Cis/Andro h): 0/0h, 4/0 h, 0/4 h, 24/0 h and 0/24 h. The results were evaluated in terms of medium-effect dose (Dm) and combination indices (CI) using the CalcuSyn software. Unlike Cis, whose activity was lower in the resistant A2780(cisR) cell line than in the parent A2780 cell line, Andro was found to be three times more active in the A2780(cisR) cell line as compared to that in A2780 cell line. Synergism was observed when Cis and Andro were administered using the sequences 0/4 h and 4/0 h. The percentage of apoptotic cell death was found to be greater for the 0/4 h combination of Andro and Cis as compared to those values from single-drug treatments. The results may be clinically significant if confirmed in vivo.
