In vitro antitumor and anti-angiogenic activities of a shrimp chondroitin sulfate.

Thrombin triggers cellular responses that are crucial for development and progression of cancer, such as proliferation, migration, oncogene expression and angiogenesis. Thus, biomolecules capable of inhibiting this protease have become targets in cancer research. The present work describes the in vitro antitumor properties of a chondroitin sulfate with anti-thrombin activity, isolated from the Litopenaeus vannamei shrimp (sCS). Although the compound was unable to induce cytotoxicity or cell death and/or cell cycle changes after 24 h incubation, it showed a long-term antiproliferative effect, reducing the tumor colony formation of melanoma cells by 75% at 100 μg/mL concentration and inhibiting the anchorage-independent colony formation. sCS reduced 66% of melanoma cell migration in the wound healing assay and 70% in the transwell assay. The compound also decreased melanin and TNF-α content of melanoma cells by 52% and 75% respectively. Anti-angiogenic experiments showed that sCS promoted 100% reduction of tubular structure formation at 100 μg/mL. These results are in accordance with the sCS-mediated in vitro expression of genes related to melanoma development (Cx-43, MAPK, RhoA, PAFR, NFKB1 and VEGFA). These findings bring a new insight to CS molecules in cancer biology that can contribute to ongoing studies for new approaches in designing anti-tumor therapy.