A Stable H1299 cells (shCtr or shM2) were treated by 5-FU (50 μM, 24 h) and then cultured alone or co-cultured with non-drug treated vehicle-treated cells stably expressing mito-mCherry in the absence or presence of Cyto B (500 nM, 24 h). The percentage of dead cells in each group was quantified. Three independent experiments were conducted. Data information: data were analyzed using two-way ANOVA with Bonferroni post-test and shown as mean ± SEM; * P < 0.05, ** P < 0.01, *** P < 0.001, ns, not significant. 