In vitro and in silico investigations of the pro-apoptotic activity of Opuntia ficus-indica cladode extracts against K562 cells

Cladodes of Opuntia ficus-indica (OFI) are thought to be an excellent source of bioactive compounds, making them an aspirant for the manufacture of health-promoting compounds. This study aims at exploring the pro-apoptotic effects of spiny and thornless OFI cladode extracts on the human immortalized myelogenous leukemia cell line (K562). The ethanol extraction method was used for preparing cladode extract. Cytotoxicity was evaluated by MTT assays. Membrane permeability/damage was detected by annexin V-binding assays, and mitochondrial damage/alteration was detected by mitochondrial membrane potential measurements. The protein expression quantities of Bax and Bcl-2 were assessed by Western blotting. The pro-apoptotic potentials of the main spiny and thornless OFI extract constituents were investigated structurally and mechanistically using protein–ligand docking and interaction profiling. Spiny OFI extract displayed a stronger cytotoxic effect than thornless OFI extract on K562 cells. In silico findings agreed with the pro-apoptotic action observed in vitro. Finally, our findings imply that OFI extracts cause apoptosis in K562 cells in order to have anti-cancer effects.