Fig. 3

Differential effect of SDF-1alpha on MDA-MB231. a Adhesion assay testing the role of different concentration of SDF-1α. 50,000 eGFP MDA-MB231 were allowed to adhere for 1 h in presence or absence of SDF-1α (50, 100, 200 ng/ml). The maximum adhesion was observed at 200 ng/ml. b F-actin polymerisation in MDA-MB231. MDA-MB231 were grown on glass bottom slides with different concentration of SDF-1α (0, 50, 100 or 200 ng/ml) and actin cytosqueletton was revealed by a phalloïdin-fluorescein (1 μg/mL) labelling (red). More stress fiber and filipods can be seen (arrows) in MDA-MB231 treated with 50 or 100 ng/ml of SDF-1α. Scale bar 20 μm. c MDA-MB231 plasticity on Matrigel. MDA-MB231 were seeded on a 96-wells plate, coated with Matrigel in presence or absence of SDF-1α (50, 100 or 200 ng/ml). Microscopic pictures of cellular networks after SDF-1α stimulation were taken after 18 h of culture. Quantitative evaluation of the cellular interconnection (white) and network (black) are presented. The evaluation was made by counting on 10 different fields. The results are expressed as means with standard error. Interconnection and network number was increased when the cells are treated with 50 or 100 ng/ml of SDF-1α. d Wound closure assay. Migration ability of MDA-MB231 was tested after a scratch in presence of different concentration of SDF-1α (0, 50, 100 or 200 ng/ml). Only 50 and 100 ng/ml of SDF-1α enhanced MDA-MB231 motility. e Migration in agarose gel assay. MDA-MB231 cells were seeded in the central well. Media only was poured in the CTRL well as control and different concentration of SDF-1α were used in the right well for the 3 wells experiments (left panel) or simultaneity in the 5 wells experiments (right panel). Pictures were taken after 8 days and the distance travelled by the cells was calculated. The histograms present the results of 3 different experiments. f Cell cycle analysis. MDA-MB231 were treated with different concentration of SDF-1α (0, 50, 100 or 200 ng/ml) for 48 h and position in cell cycle were evaluated with NIM-DAPI by flow cytometry. 50 and 100 ng/ml of SDF-1α increased the number of cells in phase S (green) and G2/M (purple) and decreased the one in G0/G1 (blue). The results presents in this figure are representative of three different experiments