Clonogenic experiments showing the survival of DU145 cells, which naturally express relatively high levels of AGT, after treatment with various agents under conditions of oxygenation or oxygen deficiency. DU145 cells (oxygenated, panel A; oxygen-deficient, panel B), were treated with varying concentrations of KS119 (▲), 90CE (■), or Onrigin (●). The vertical axis indicates the percent survival over untreated controls; the horizontal axis indicates the concentration of the agent employed in μM. Oxygen depleted samples were treated for 24 h in the presence of 2 U/ml of glucose oxidase, 120 U/ml of catalase and 25 mM glucose, before harvesting and plating of cells to measure cloning efficiency. All points are the result of at least three independent experimental determinations ±SEM.