Benzimidazole derivatives as dual EGFR and BRAF^V600E inhibitors with pro-apoptotic antiproliferative potential

Resistance to single-target kinase inhibitors is increasing, necessitating the development of multi-target-directed medications that can simultaneously affect different carcinogenic pathways. The objective of this investigation was to develop, synthesize, and evaluate the pharmacological properties of a novel set of compounds that are derived from benzimidazole and thereby inhibit both EGFR and BRAF^V600E. Compounds 8c, 8d, and 8f were identified as the most potent candidates in in vitro enzymatic and antiproliferative investigations. Compound 8d exhibited the most potent dual inhibitory activity, with IC₅₀ values of 7.17 nM against EGFR and 45.50 nM against BRAF^V600E. These values were comparable to those of the reference medications vemurafenib (IC₅₀ = 41.38 nM) and erlotinib (IC₅₀ = 5.40 nM). Mechanistic studies have shown that compounds 8d and 8f strongly induce apoptosis, primarily through the intrinsic (mitochondrial) pathway, as evidenced by significant activation of caspase-9 and caspase-3. The experimental results were confirmed by molecular docking studies, which showed that compound 8d exhibits strong binding affinity for both the EGFR and BRAF^V600E kinase domains. The in silico ADME profiling and drug-likeness analysis revealed that compound 8d exhibits high gastrointestinal absorption and adheres to Lipinski's rule of five, supporting its potential as an oral therapy.