Figure 3.

Endothelial cells slightly decrease breast cancer cell proliferation and migration on plastic, but increase their invasive morphogenetic properties in matrix gels. (A) MMT cell proliferation in response to the replacement of 30% culture medium by MSS-31 cell conditioned media, or their culture medium as a control, was measured after a 3-day culture. Values are representative of 3 independent experiments. (B) MMT cells were seeded upon Transwell^® inserts, and cultured in wells where MSS-31 endothelial cells (or no cells in the control condition) had been previously seeded. Values are means of 3 independent experiments. (C) MMT subconfluent cultures were wounded and incubated with MSS-31 cell conditioned media or their culture medium as a control. Images were acquired after a 24-h period of incubation, and show that Ets-1-driven MMT cell migration within the wound is decreased by endothelial cell conditioned media. (D) MMT cells were cultured within three-dimensional matrix gels, above which MSS-31 cells were deposited (bottom lane) or not (upper lane). Images were acquired following a 1-week culture and evidence endothelial cell-driven stimulation of cancer cell invasive branching morphogenesis. (E) Quantification of primary branch thickness was performed with ImageJ software and the results are plotted in the displayed graph. ^**P<0.01; NS, non-significant. Scale bars, 100 µm.