FIGURE 7:

The α5β1-integrin adhesive bond is required for the tension-dependent malignant behavior of MEC organoids. (A) Immunofluorescence confocal images (bottom) and phase-contrast images (top) of 3D cultures of α5/FN9–10 WT and α5/FN9–10 Syn. Site mutant nonmalignant MECs stained nuclear YAP. (B) Second harmonic generation images of nonmalignant (MCF10A) human mammary epithelial day 20 acini (green), expressing empty vector or elevated α5 integrin with FN and with or without FN synergy-site inhibitor, embedded in collagen (blue) and installed into a 3D tension bioreactor system and subjected either to 0% (400 Pa) or 10% (4000 Pa) stretch. Arrows in B indicate invasive cells, and colony circularity (left) and area (right) are quantified in C. Results are the mean ± SEM of three separate experiments with at least 10 acini analyzed per each condition each time. ***, p < 0.001,one-way ANOVA. Scale bars: 50 μm.