Assessment of the Inhibitory Effects of Ficin-hydrolyzed Gelatin Derived from Squid (Uroteuthis duvauceli) on Breast Cancer Cell Lines and Animal Model

Marine novel natural products have been applied for cancer therapy. Enzyme-digested gelatin hydrolysates have proven to serve as promising sources of potent biologically active peptides. Potential anti-breast cancer properties of the extracted Ficin-digesterd gelatin hydrolysate from Indian squid (Uroteuthis duvauceli) was extensively characterized by cellular and animal models. Gelatin was extracted from squid skin, hydrolyzed by Ficin, and characterized by standard physico-chemical methods. Ficin-digested gelatin hydrolysate was used at various doses of 0-0.1 mg/mL for assessment of MCF-7 and MDA-MB-231 breast cancer cells versus HUVEC normal cells. Cytotoxicity, phase-contrast morphological examination, apoptosis/necrosis, clonal-growth, cell-migration, Matrix-metalloproteinases (MMPs) zymography, and Western blotting were used for cellular assessments. For animal studies, breast tumor-induced BALB/c mice received hydrolyzed gelatin regimen, followed by tumor size/growth and immune-histochemical analyses. Significant inhibition of MCF-7 and MDA-MB-231 with no cytotoxicity on HUVEC cells were detected. Apoptosis was increased in cancer cells, as revealed by elevated ratio of cleaved caspase-3 and PARP. MMP-2 and MMP-9 activities in both cancer cells were diminished. In mice, gelatin hydrolysate prevented weight loss, decreased tumor size, induced p53, and down-regulated Ki67 levels. These findings suggest that Ficin-digested gelatin hydrolysate could be a beneficial candidate for novel breast cancer therapies.