miR-21 downregulation abrogates G2/M check point accumulation after irradiation. (A) T47D cells were infected with empty lentivirus (+ EV), with miR-21 overexpressing LV (+ miR-21) or inhibitory miR-21 LV (+ anti-mir-21) and analysed for cell cycle changes 24 hours after 5 Gy irradiation. One representative FACS analysis is shown from three independent experiments. (B) Statistical analysis of subG1 cellular fraction in T47D infected cells (as in part A) and (C) in MDA-MB-361 cells (control cells - light gray boxes) or after 5 Gy irradiation (dark gray boxes). Data represent the means ± SD (n=3). *p <0.05, **p <0.01 by ANOVA.