Saringosterol acetate isolated from Hizikia fusiforme, an edible brown alga, suppressed hepatocellular carcinoma growth and metastasis in a zebrafish xenograft model

Saringosterol acetate (SSA) was isolated from an edible brown alga Hizikia fusiforme. In this study, we developed an adult zebrafish human hepatocellular carcinoma (HCC) xenograft model to confirm that SSA inhibits tumor growth and metastasis. Established Hep3B cells labeled with the fluorescent tracker CM-Dil were xenografted into the abdominal cavity of zebrafish once every three days for one month. Compared with the control group, the fish injected with Hep3B showed a significant increase in α-fetoprotein (AFP) and factors related to tumor growth and metastasis (IL-6, TNF-α, TGFβ, MMP2, and MMP9). Using the model, it was proven that SSA affected survival rate, AFP production, and the levels of factors related to tumor growth and metastasis via the PI3K/AKT/mTOR and TGFβ/Smad pathways. In conclusion, this HCC model can be used for in vivo experiments to investigate the inhibition of cancer, and SSA may be useful for the treatment of cancer. •Saringosterol acetate (SSA) isolated from an edible brown alga Hizikia fusiforme.•SSA suppresses the growth of hepatocellular carcinoma in zebrafish xenograft model.•SSA inhibits tumor growth and metastasis by inhibiting cytokines and MMPs.•Anti-tumor effects of SSA by regulating the PI3K/AKT/mTOR and TGFβ/Smad signaling.