Fucoidan from Sargassum hemiphyllum (Turner) C. Agardh inhibits human hepatoma cell (HepG2) through cell cycle arrest and apoptotic induction

Cancer has become one of the most serious diseases threatening human health, while traditional chemotherapeutic drugs have serious side effects. Drugs of marine origin have attracted many scholars due to their remarkable effectiveness, low drug resistance and low adverse reactions. In this study, the fucoidan DF1 and DF2 extracted from Sargassum hemiphyllum (Turner) C. Agardh were used to explore their effects on induced HepG2 hepatoma cell apoptosis and their relevant molecular mechanisms of apoptosis in HepG2 cells were analyzed by flow cytometry and western blotting assay. DF1 and DF2 could induce excess intracellular reactive oxygen species (ROS) production in HepG2 cells and lead to stimulation of the mitochondrial apoptotic pathway, up-regulate the protein expressions of Bax, Cytochrome C and Cleaved-Caspase-3/8, and down-regulate the protein expressions of Bcl-2 and Caspase-3/8/9. Meanwhile, DF1 and DF2 could induce HepG2 cell cycle arrest in the S-phase and up-regulate the protein expression of p21, and down-regulate the expression of Cyclin A and CDK2. This study provides a scientific basis for the development of V_C/H₂O₂-treated fucoidans as anticancer drugs or adjuvant drugs.