Mechanism-guided discovery of chromene-chalcone hybrids targeting PKM2 and microtubules for breast cancer therapy

This study presents the rational pharmacophore design, synthesis, and biological evaluation of new chromene-chalcone hybrids (CCHs) with dual mechanisms involving pyruvate kinase M2 (PKM2) inhibition and microtubule stabilization for their potential as anticancer agents. The synthetic route involved the formation of a chromene aldehyde 29 via an oxa-Michael addition followed by intramolecular cyclization, which subsequently underwent Claisen Schmidt condensation to afford the final chalcone derivatives. Among the synthesized compounds (30a-30o), 30o emerged as the most promising candidate, exhibiting potent anticancer activity through dual targeting of PKM2 and the microtubule network. Compound 30o demonstrated a significant antiproliferative effect against MCF-7 breast cancer cells, with an IC₅₀ value of 10.2 ± 0.07 μM, and showed PKM2 enzymatic inhibition with an IC₅₀ of 0.363 ± 0.12 μM, as confirmed through enzymatic assays and protein expression. Cell cycle analysis revealed 30o induced G2/M phase arrest and microtubule-stabilizing activity. Furthermore, molecular modeling studies revealed its binding mode and strong interactions within the PKM2 active site and taxol binding site of tubulin, supporting the experimental findings. ADMET profiling predicted favorable pharmacokinetic and drug-likeness properties, highlighting its potential as a lead compound. Together, these findings underscored compound 30o as a dual-acting anticancer agent, simultaneously targeting cancer metabolism and cytoskeletal integrity, and offered a promising scaffold for further development in breast cancer therapeutics.