Fig. 3

Metformin decreases RAD51 protein stability. a Hs 578T and MDA-MB-231 cells were pretreated with 5 mM metformin or control diluent (mock) for 24 h, followed by 5 μM cycloheximide (CHX) treatment for 0.5 to 6 h to block protein synthesis. The cells were harvested at the indicated time points after CHX treatment and immunoblotted for RAD51 or β-actin (loading control). Results represent the mean ± SEM of five independent experiments. #, ## vs. CHX treatment alone. b Hs 578T and MDA-MB-231 cells were pretreated with cisplatin (5 μM) or metformin (5 mM) for 24 h, followed by CHX treatment (5 μM). Results represent the mean ± SEM of five independent experiments. #, ## vs. cisplatin treatment alone; ^#P < 0.05, ^##P < 0.01 by one-way ANOVA followed by Bonferroni’s post hoc test