Endothelial cell secreted factors induce an invasive phenotype. (a) Schematic for the generation of HUVEC-CM. (b) Representative confocal images of immunostained MDA-MB-231 treated with or without HUVEC-CM (scale bar = 20 μm). (c) Circularity was measured from cells treated with or without HUVEC-CM (n = 3 biological replicates, data points represent individual cells, error bar represents standard deviation). (d) Average number and size of pFAK adhesions per cell of MDA-MB-231 treated with or without HUVEC-CM (n = 3 biological replicates, data points represent individual cells, error bar represents standard deviation). (e) Motility of cells treated with CTRL-CM or HUVEC-CM as analyzed using the Incucyte live cell imaging platform (n > 40 cells per condition, data points represent individual cells, error bar represents standard deviation). (f) Migration plot of MDA-MB-231 treated with CTRL-CM or HUVEC-CM (n > 40 cells per condition). (g) Representative fluorescent confocal projections depicting invasion of MDA-MB-231 when treated with HUVEC-CM (top) or CTRL-CM (bottom) (scale bar = 200 μm). (h) Corresponding quantification of invasion distances of MDA-MB-231 (n = 3 biological replicates, data points represent individual cells, error bar represents standard deviation). *p < 0.05, **p < 0.01, ****p < 0.0001.