Caffeic acid-conjugated chitosan derivatives and their anti-tumor activity

In this study, we synthesized caffeic acid (CFA)-conjugated chitosan (ChitoCFA) as an anti-cancer compound. CFA was conjugated to the amine groups of chitosan (ChitoCFA) and its chemical composition was confirmed using 1 H nuclear magnetic resonance spectra, which indicates that specific peaks of CFA was observed at ChitoCFA conjugates. The anti-cancer effects of CFA and ChitoCFA were studied using CT26 colorectal carcinoma cells. In this cytotoxicity study, CFA and ChitoCFA revealed a dose-dependent decrease of cell viability while chitosan had lower cytotoxicity against tumor cells. CFA and ChitoCFA also proved an anti-proliferative effect against tumor cells. In comparison with CFA, ChitoCFA may accelerate an apoptosis of tumor cells. Furthermore, ChitoCFA demonstrated good anti-invasive efficacy at Matrigel ® invasion assay against tumor cells. We suggest that ChitoCFA is a promising candidate as an anti-cancer compound.