Treatment with AdHTVP2G5-rev-casp3 sensitizes OVCAR3 cells to subsequent flavopiridol exposure. A and B: Cell viability and apoptosis determined by CCK-8 assay and flow cytometry. OVCAR3 cells were infected by AdHTVP2G5-rev-casp3 alone at different MOIs as indicated, or 72 hs later, followed by flavopiridol (300 nM) for 48 hs. The results demonstrate the combination treatment can produce significant synergism of cell-killing effect using AdHTVP2G5-rev-casp3 at MOI of 5 ~ 40. The standard deviation for triplicate wells was less than 10%. C: Cells were infected with AdHTVP2G5-rev-casp3(MOI = 20) alone for 72 hs(rAd72 h), or 300 nM flavopiridol alone for 24 hs or 48 hs(300 F 24 h and 300 F 48 h, respectively). Alternatively, cells were infected with AdHTVP2G5-rev-casp3(MOI = 20) for 0 ~ 72 hs, followed by 300 nM flavopiridol for 48 hs (20 rAd 0 ~ 72 h + 300 F 48 h) or AdHTVP2G5-rev-casp3(MOI = 20) for 72 hs, followed by 300 nM flavopiridol for 24 hs(20 rAd 72 h + 300 F 24 h). Results demonstrate the sequential dependence of the AdHTVP2G5-rev-casp3/flavopiridol combination. Administration of the sequential 20 rAd 72 h + 300 F 48 h combination was more effective than other combinations.