Fig. 1
Metformin increases the sensitivity of prostate cancer cells to docetaxel. A PC-3 cells were cultivated in the presence of DCX (0.625–15 nM) and/or MET (2.5–10 mM) for 48 h, harvested, and counted with Coulter counter. B PC-3 WT motility was estimated directly after DCX (2.5 nM) and/or MET (10 mM) administration with time-lapse videomicroscopy. Cell trajectories are depicted as circular diagrams (axis scale in micrometers) drawn with the initial point of each trajectory placed at the plot origin (registered for 8 h; N > 50). Dot plots and column charts show movement parameters at the single-cell and population level, respectively (plotted as percentage of control; cf. Additional file 1: Fig. S1A). C Apoptotic response of PC-3 WT cells estimated after the long-term DCX and/or MET treatment (2.5 nM/10 mM) with annexinV/PI assay. Compensated dot plots comprise 50,000 events, classified on the basis of their bright-field ratio (cf. Additional file 1: Fig. S1B). D Effect of the long-term (48 h) DCX/MET (2.5 nM/10 mM) treatment on PC-3 viability, estimated at the population level with MTT (upper panel) and ATP assay (lower panel). E Cytoskeleton architecture (F-actin: red, vinculin: green, DNA: blue) and motility estimated in long-term (48 h) DCX and/or MET (2.5 nM/10 mM) treated PC-3 WT cells (cf. Additional file 1: Fig. S1C). F Metabolic profile after the long-term (48 h) DCX/MET (2.5 nM/10 mM) treatment estimated with MTT (left), ATP (middle), and lactate assay (right) and calculated per 105 cells. The statistical significance of the differences was tested with Student’s t-test (in A, C, D, F), or by one-way ANOVA followed by post hoc Tukey’s HSD (in B, E). #P ≤ 0.05 versus untreated control; *P ≤ 0.05 as indicated in the charts or 0 mM MET in A. All results are representative of at least three independent experiments (N ≥ 3). Error bars represent SEM. Note that MET increases DCX sensitivity, NAD(P)H/ATP levels, and lactate production in PC-3 cells