Abstract: Objective: To evaluate the effects of Taxol on the cytoskeleton of different ovarian cells and to prove that there may be a different mechanism of action for Taxol other than through microtubulin stabilization. Methods: A human ovarian cancer cell line (0VCA-420) and the solid component from six recently isolated epithelial ovarian tumors were exposed to Taxol(20uM and 50nM).The cells were evaluated for differences in the cytoskeleton by immunostaining for tubulin and actin.Results: Multimininucleation, which is consistent with apoptotic nuclei, was identified using Hoerscht D N A staining. All the cells exhibited an organized cytoskeleton when stained for actin. The control OVCA-420 cells had an extensive fibrillar tubulin organization around the nucleus which did not change in appearance after treatment which Taxol, despite the multimininucleation which occurred. In contrast, the control cells (for example HS-1) had diffuse, punctate tubulin which then accumulated in bundles at the sites of frequent mininuclei after treatment with Taxol. The other cells (for example HS-2), after treatment with Taxol, accumulated tubulin around the periphery of the nucleus. However, there was no evidence of multinucleation. Conclusions: The effect of Taxol on tubulin varies between ovarian cancer cell populations, but is homogenous within a cell population. There also appears to be a dissociation between tubulin response to Taxol and multimininucleation. Therefore, there may be a different mechanism of action for Taxol other than through microtubulin stabilization.