Modulation of Ionizing Radiation-Induced G2 Arrest by Cyclooxygenase-2 and its Inhibitor Celecoxib

COX-2 appears to prolong IR-induced G2 arrest by upregulating ATR. Celecoxib downregulated ATR preferentially in irradiated COX-2 overexpressing cells. Celecoxib may radiosensitize cancer cells by inhibiting G2 arrest through ATR downregulation.