Study on the anticancer function and mechanism of cathelicidin-DM in liver cancer.

BACKGROUND: Previous studies have shown that bioactive molecules secreted by toad skin possess anticancer properties. Cathelicidin-DM (C-DM) is a bioactive peptide secreted by toad skin, but its effects on tumor cells and the underlying molecular mechanisms remain unknown. METHODS: The impact of varying amphibian peptides on the viability of various tumor cells was determined by CCK-8. The influence of C-DM on liver cancer (LC) cell function was investigated using colony formation, flow cytometry, and Transwell. The anti-tumor activity of C-DM was evaluated by xenograft models. RNA-seq was done to confirm differentially expressed genes (DEGs), which were subject to GSEA. Cellular experiments were performed to verify the molecular regulatory mechanism of C-DM in LC. RESULTS: C-DM (100 μg/mL) had a significant repressive impact on the proliferation, migration, invasion, and cell cycle progression of HepG2 and Hep3B cells, and facilitated apoptosis. In vivo experiments validated the anti-tumor impact of C-DM, while its toxicity was low. DEG DHRS3 was enriched in the JAK-STAT pathway. Overexpression of DHRS3 fostered the malignant phenotype of LC cells and activated the JAK-STAT pathway. However, the addition of C-DM weakened the oncogenic properties of DHRS3 and repressed the JAK-STAT pathway. CONCLUSION: C-DM exerted an anti-LC effect by downregulating DHRS3 and mediating the JAK-STAT pathway, indicating that C-DM may be a promising candidate drug for LC treatment.