Cells were treated with MLN4924 at 100 nM for 24 hrs (A-C) or up to 48 hrs (D), alone or in combination with radiation (6 Gy), followed by FACS analysis for cell cycle profiling (A), cell cycle distribution (B), cell population with >4N DNA content (C), and sub-G1 population for apoptosis (D). Shown is mean ± SEM, (n = 3): *, p<0.05. One representative result is shown for (A).