Fucoidan from Spatoglossum schröederi promotes B16-F10 malignancy features modulation and antimelanoma in vivo activities

Although recent advances in targeted and immunotherapy, metastatic melanoma treatment still poses as a challenge, with limited success and a variety of severe adverse effects. Polysaccharides from natural sources have been explored as a new approach to tackle cancer and melanoma treatment limitations, even reaching clinical trials. One prominent group of biological active polysaccharides are fucoidans - sulfated polysaccharides mainly constituted of fucose and obtained from brown seaweed. In the present study, we explored the antimelanoma activities of Fucan A, a highly sulfated fucoidan obtained from Spatoglossum schröederi. Fucan A presented a selective antiproliferative effect against murine melanoma B16-F10 cell line impacting cell cycle progression in concentrations of 100 and 1000 μg⸱mL−1 while also reducing its colony formation and invasive capacity, as well as modulating invasion mechanistically related genes - namely MMP-9, MMP-14, glypican-3 and perlecan. Fucan A also reduced in vivo solid tumor volume in a daily post-cell inoculation treatment regimen with a 100 mg⸱Kg−1 dosage. Additionally, using a 48 h pre-treatment regimen in a reduced dosage (30 mg⸱Kg−1), Fucan A reduced pulmonary metastasis colonization, with limited to non-detectable adverse effects. These results associated with the explorable commercial potential of S. schröederi indicate an interesting compound to be further explored as a possible antimelanoma drug.