AZD7762 inhibits Chk1 and Chk2 activity in U251 cells. U251 cells were pretreated for 1 hour with DMSO or AZD7762 (100 nM) and treated with and without radiation (6 Gy). Three hours later, cells were lysed and extracts were immunoblotted for cdc25A, phospho-Chk1 (S345 and S296), Chk1, Chk2, phospho-H2AX (S139), and phospho-p53 (S15). GAPDH was shown as equal loading control.