Fig. 6.
Metabolic activation of KS119 using high densities of DU145 and EMT6 cells. For these experiments, 107 cells/ml were incubated with KS119 (DU145 cells, panel A; EMT6 cells, panel B) under oxygenation (■) or oxygen deficiency (▲) for various periods of time. Cells suspension samples were withdrawn, mixed with an equal volume of acetonitrile to lyse cells, quench all reactions, extract drug, and precipitate proteins. These mixtures were then allowed to stand for 15 min at room temperature, then centrifuged at 10,000 × g for 5 min and the supernatants were analyzed by HPLC. The Y-axis indicates drug concentrations as measured by absorbance at 280 nm. All points are the result of at least three independent experimental determinations ±SD.