Figure 1

Mebendazole and vincristine have similar inhibitory effects on cell viability and microtubule polymerization. (A,B) Western blots illustrating microtubule depolymerization caused by incubation of GL261 cells with the indicated concentrations of mebendazole (MBZ) and vincristine (VCR). Cells were processed, and polymerized (P) and soluble (S) tubulin were separated by centrifugation as described in Materials and Methods. (C,D) Concentration dependence of microtubule polymerization and cell viability: (C) mebendazole, (D) vincristine. Microtubule polymerization was determined as the percentage of polymerized tubulin over total tubulin. Determination of cell viability was performed as described in Materials and Methods. Data shown were normalized to vehicle control values and represent the mean ± SEM of three and at least eight independent experiments for the microtubule polymerization and cell viability experiments, respectively.