Fucoidan from brown algae Fucus evanescens potentiates the anti-proliferative efficacy of asterosaponins from starfish Asteropsis carinifera in 2D and 3D models of melanoma cells.

This study was aimed to determine the efficacy of combination of fucoidan from the brown algae Fucus evanescens (FeF) or its derivatives with thornasteroside A (ThA) or asteropsiside A (AsA) from the starfish Asteropsis carinifera in combating human melanoma cells. In vitro MTS and soft agar methods were performed to determine effect of FeF, its derivatives, ThA, AsA or their combination on proliferation and colony formation of SK-MEL-28 cells in 2D and 3D culture. Desulfation of FeF, but not deacetylation, led decreasing of its Mw and anti-proliferative activity. The combinatorial effect of FeF with ThA and AsA depended on the sequences of treatment by compounds. There was additive anticancer effect of FeF with ThA or AsA during simultaneous treatment of cells. ThA and AsA were not active against SK-MEL-28 cells after their pre-treatment with FeF. Potential synergism of action was identified only when SK-MEL-28 cells were pre-treated with ThA and AsA and then by FeF. This process going through the regulation of MEK1/2/ERK1/2/MSK1 pathway and expression of the cell cycle proteins as determined by Western Blot. Thus, the combination of fucoidan with the asterosaponins opens up the prospects for the development of effective combined chemotherapeutic methods for melanoma treatment.