A new marine-derived sulfated polysaccharide from brown alga suppresses tumor metastasis both in vitro and in vivo.

Herein, we report that marine-derived sulfated polysaccharide (MSP), a new kind of polysaccharide extracted from brown alga, exhibits the anti-migration effect in vitro and potently suppress metastasis of Lewis lung carcinoma in vivo. Adhesion assays demonstrated that MSP inhibits the heterogenous adhesion on fibronectin. Further studies revealed that MSP decreased FN-induced MDA-MB-435 migration, accompanied by its potent regulatory effect on actin filament reassembling. In addition, MSP significantly inactivated the phosphorylation of FAK and subsequent ERK1/2 in MDA-MB-435 cells. All these actions may be the results of MSP binding to FN, promising the therapeutic potential of MSP in tumor metastasis.