Synergistic targeting of cancer-related proteins by benzyl isothiocyanate and caffeic acid: MLSD and cytotoxic mechanisms in MCF-7 cells

Abstract

This study investigated the synergistic cytotoxic effects of benzyl isothiocyanate (BITC) and caffeic acid (CA) on human breast adenocarcinoma (MCF-7) cells. Cell viability assays (MTT) revealed that BITC induces reactive oxygen species (ROS)-mediated cell death, while CA alone exhibited minimal cytotoxicity. Notably, their combination selectively enhanced MCF-7 cell death with limited effects on human fibroblasts. Mechanistic investigations demonstrated MAPK pathway activation and apoptosis induction, supported by altered expression of GST, p38, p-ERK, ERK 1/2, Nrf-2, and Bcl-2 proteins. Fluorometric analysis revealed significant disruption of redox homeostasis, including changes in ROS, glutathione (GSH), and caspase-3/7 activity. Molecular docking studies confirmed stable binding interactions (binding energies: –4.9 to –6.8 kcal/mol) of BITC and CA with key cancer-related proteins (ERK2, p38 MAPK, Bcl-2, Keap1-Nrf2, GST). Furthermore, Multiple Ligand Simultaneous Docking (MLSD) demonstrated the cooperative binding of BITC and CA to shared and distinct residues within the same protein targets, revealing enhanced binding affinity and potential synergistic inhibition of oncogenic pathways. These results highlight the synergistic potential of BITC and CA to modulate the MAPK pathway, disrupt cellular homeostasis, and induce apoptosis, underscoring their promise for combination cancer therapy.