Novel Imidazopyridine–Oxadiazole β-Tubulin Inhibitors Suppress Breast Cancer Migration and Induce Caspase-3-Mediated Apoptosis

A series of novel imidazo-[1,2-<i>a</i>]-pyridine-oxadiazole (<b>iMPZ1-15</b>) hybrid compounds was designed as potential β-tubulin polymerization inhibitors, inspired by the cis-conformation and biaryl scaffold of combretastatin A-4. The effects of <b>iMPZ</b> beta-tubulin inhibitors on proliferation in MDA-MB-231, SH-SY5Y, and DLD-1 cancer cells, as well as their influence on beta-tubulin inhibition, colonization, cell migration, cell cycle progression, and apoptosis in MDA-MB-231 cells, were investigated. <b>iMPZ-8</b> identified as the most efficacious treatment candidate, with an IC₅₀ value of 7.5 μM in MDA MB-231 cells. <b>iMPZ-8</b> had a comparable effectiveness to NOC, which served as a positive control for beta tubulin inhibition. <b>IMPZ-8</b> reduced cellular migration and colonization. It also accumulated throughout the G2/M phase of the cell cycle, through the BAX-Caspase-3 intrinsic apoptotic signaling pathway.