Fig. 6

RhoGTPase modulation in a co-culture settings of MDA-MB231 and BMHC. a Western blot analysis. MDA-MB231 were sorted after a 2 days or 5 days of co-culture with BMHC as the chart presented in Fig. 2b. Co-culture increased the level of Rac1(up left panel) and Cdc42 (bottom left panel) but decreased Rhoa and Rock2 (middle panel) in MDA-MB231. The pixel density of each band has been divided by the corresponding actin band and then by the control of the experiment. The results are represented in the right histogram. b Adhesion assay. BMHC were plated up to 60 % confluency, 50,000 eGFP MDA-MB231 were allowed to adhere for 1 h in presence or not of SDF-1α and a Rac1 inhibitor (NSC23766). Plastic was used as negative control. Rac1 inhibition significantly decreased the adhesion of MDA-MB231 to BMHC. c Western blots analysis. MDA-MB-231 Mock or ShRac1, serum-starved for 24 h, were treated with SDF-1α (200 ng/ml) for 4 h. Western blots against integrin αV, β1, and β3 were performed. d Proliferation assay. MDA-MB231 Mock or ShRac1 were plated and counted every 2 days in presence of BMHC during 6 days in serum free condition. Images represent the co-culture of BMHC and MDA-MB231 Mock (left) or ShRac1 (right) in phase microscopy. Scale bar 250 μm. The chart represents the proliferation curve of MDA-MB231 Mock (black circle) or ShRac1 (white circle). BMHC were able to increase proliferation of MDA-MB231 Mock but not the ShRac1 one. e Cell cycle analysis. MDA-MB231 were treated with SDF-1α (50 ng/ml) and a Rac1 inhibitor (NSC23766) for 48 h and position in cell cycle were evaluated with NIM-DAPI by flow cytometry. The inhibition of Rac1 reversed the effect of SDF-1α on the cell cycle position of MDA-MB231