p190RhoGAP overexpression leads to apoptosis. (A) Immunofluorescent images of MDA-MB-468 cells transiently overexpressing HA-p190 represent the 3 observed phenotypes: multinucleation, dendrite-like formation, and apoptosis. Panels a-c: DAPI-stained DNA; panels d-f: triple HA-tagged p190; panels g-i: TUNEL; and panels j-l: phase. Arrows identify p190-overexpressing cells that are multinucleated (panels a, d, g, and j), dendritic-like (panels b, e, h, and k), or apoptotic (panels c, f, i, and l). (B-E) Quantitation of the respective phenotypes observed in mock-treated, vector control (VC), or p190-transfected MDA-MB-468 (B), MCF10A (C), vSrcNIH3T3 (D), and NIH3T3 (E) cells. Results are expressed as the mean percentage of total cells (mock or VC) or cells positive for HA-p190 that exhibited the observed phenotypes ± standard error of the mean (SEM) (n > 3).