Fig. 3

Immunohistochemical characterization of PTX-induced cytotoxic effect in U87MG xenografts. Representative immunostaining with markers of mitotic spindles (α-tubulin) and of centrosome (γ-tubulin) showing mitotic alterations in brain tumor xenografts. In brain xenografts containing PTX-loaded MSCs, there was a strong increase in aberrant spindle configurations, mainly resulting in multipolar spindle mitoses (a) and in centrosome number defects (b) (white arrows). Scale bars = 10 μm. Multipolar spindles of tumor cells in the PTX-MSCs/U87MG grafts are significantly higher with respect both to tumor xenografts derived by injection of U87MG cells alone and to tumors generated by the injection of U87MG cells and unloaded MSCs (c). DAPI 4′,6-diamidino-2-phenylindole, GFP green fluorescent protein, MSC mesenchymal stem/stromal cell, PTX paclitaxel