Fig. 5.

The toxic interaction between PDE5 inhibitors and chemotherapy is associated with increased plasma membrane levels. Bladder T24 cells were grown in chamber slides. Twenty-four hours after plating cells were treated with vehicle, sildenafil (SIL, 2 μM), mitomycin C (MITO, 100 nM), DOX (200 nM), Gemzar (50 nM) as indicated. Cells were fixed 6 hours after exposure, and the cell surface levels of CD95 under each condition were determined by immunohistochemistry. DAPI, 4′,6-diamidino-2-phenylindole; FITC, fluorescein isothiocyanate.