Figure 4

Effects of AR-18 on gemcitabine sensitivity. A. Growth inhibitory effect of AR-18 (2.5–50 μM), gemcitabine (0.05–1.0 μM), and their combination in a 200:1 AR-18 to Gemcitabine ratio was measured by the SRB proliferation assay in MIA PaCa-2 and BxPC-3 after 48 h of exposure. Each point represents mean from three experiments, each with six replicates; error bars = ± SEM. Gem: gemcitabine. The results are indicated by relative cell proliferation as a percentage of solvent control. B. Growth inhibitory effect of AR-18 (10–50 μM), gemcitabine (0.001–1.0 μM), and their combination was measured by the SRB proliferation assay in PANC-1, HPAC, PK-1, and PK-8 cell lines after 48 h of exposure. Each point represents mean from three separate experiments, each with six replicates; error bars = ± SEM. Gem: gemcitabine. The results are indicated by relative cell proliferation as a percentage of solvent control. C. Effect of AR-18 (10–50 μM), gemcitabine (0.001–1.0 μM), and their combination on colony-forming capacity of PANC-1 and BxPC-3 cells was measured by colonogenic assay. Control cells were given vehicle solution. Means for four separate experiments, each with three replicates; error bars = ± SEM. Gem: gemcitabine. The results are relative to vehicle treated control.