Fig. 6.

Gossypol preferentially inhibits cell viabilities in cancerous cells but not in normal cells. A, Gossypol reduces cell viabilities in multiple cancer lines in a dose-dependent manner. Serum-starved cells were incubated with vehicle (DMSO) as the control or with gossypol of different doses (0.25, 0.5, 1, 2, 4, 6, 8, 10, and 12 μm) for 24 h. The number of viable cells with different treatment was determined by MTS assays. Collected data were normalized to the DMSO treatment control, in which the number of viable cells was set to 100%. Each data point represented the average of relative values derived from three wells of cells treated with gossypol at the indicated dose. The concentration of gossypol providing 50% inhibition of viable cells, IC₅₀, was determined by constructing the dose-response curve. To derive the dose-response curve, the Hill-Slope model, y = Min + $\frac{Max-Min}{1+{10}^{\left(IC50-S\right)+slope}}$ was applied to fit the dose-response data. B, Gossypol preferentially reduces cell viabilities in cancerous cells but not in normal cells. Serum-starved mouse primary hepatocytes and hepatocarcinoma HepG2 cells were incubated with gossypol of different concentrations for 24 h, and viable cell numbers were determined as above. In HepG2 cells, gossypol caused a sharp decrease in the number of viable cells with doses higher than 2 μm. By contrast, primary hepatocytes survived even when the concentration of gossypol is as high as 12 μm.