Exploring natural protease inhibitors: Evaluating cytotoxic effects on cancer cell lines

Abstract

Protease inhibitors, whether natural or synthetic, show promise in cancer treatment by targeting dysregulated proteolytic activity linked tumor progression and metastasis. This study evaluated trypsin inhibitory activity and cytotoxic effects of selected plant extracts. Screening twenty six plant extracts revealed twelve extracts contain trypsin inhibitors and eighteen plant extracts showed cytotoxicity to HT29 cell line with the highest cytotoxicity shown by Senna alatta extract (98.45±0.44%). Plant extracts containing protease inhibitors when subjected to proteinase K digestion, the protease inhibitor activity as well as cytotoxicity was reduced. For example, extracts from C. curviflora, S. alata, and G. nervosa showed high trypsin inhibition as well as cytotoxicity and both reduced on proteinase K treatment. This indicates that there is some correlation between cytotoxicity and trypsin inhibition (r = 0.52) and proteinaceous trypsin inhibitors or other proteins are involved in the cytotoxicity. These findings highlight the potential role of the trypsin inhibitors in cytotoxicity against cancer cell lines.