demonstrates preferential cytotoxicity in prostate cells. LNCaP, PC3AR, U251MG, and HeLa cells were seeded at 1.25 × 104 cells/well in a 96-well plate and infected with Ad/FasL-GFPTET, Ad/FasL-GFPPS/TR, Ad/FasL-GFPPFLPS, Ad/FasL-GFPDiSTRES, or 1× HBS (mock) in the presence of 30 nM DHT. LNCaP, PC3AR, U251MG, and HeLa were infected at MOI 10, 5, 5, and 2.5, respectively. Three days post-infection, cells were fixed with methanol and then assayed for cytotoxicity using crystal violet assay. Since each cell type showed varying sensitivities to adenovirus-delivered FasL-GFP, we infected each cell type at MOI values determined during pilot studies to induce maximal cytotoxicity in response to Ad/FasL-GFPTET control. Percent viability was calculated by dividing the mean absorbance of each sample by the mean absorbance of 1× HBS mock infection for each cell line and then multiplying by 100%. MOI values were based on pfu/ml. Horizontal line delineates 100% viability.