Cod Skin Oligopeptide Inhibits Human Gastric Carcinoma Cell Growth by Inducing Apoptosis

Aim: To investigate the effect of cod skin oligopeptide (CSO), a natural hydrolysis product obtained from Pacific cod skin gelatin, on the growth of human gastric cancer cells. Methods: Morphological changes were observed in CSO-treated BGC-823 cells under a microscope. The viability of BGC-823 cells was examined by cell counting kit-8 assay. The efficacy of CSO in vivo was evaluated using a xenograft tumor model. Apoptotic cells were identified by flow cytometry. Pro-apoptotic protein expression was verified by western blotting. Results: CSO significantly inhibited BGC-823 cell growth in a dose- and time-dependent manner in vitro and also inhibited the growth of murine gastric cancer xenografts. Flow cytometric assays showed that treatment of BGC-823 cells with CSO significantly increased the percentage of apoptotic cells. Mechanistically, CSO effectively induced expression of pro-apoptotic cleaved caspase-3 and cleaved caspase-9 and down-regulated anti-apoptotic Bcl-2. Conclusion: CSO inhibits gastric cancer cell proliferation while inducing apoptosis by modifying the expression of pro-apoptotic proteins, suggesting a potential therapeutic role for CSO in gastric cancer treatment.