Fig. 5: CAF-S1 promote proliferation and initiate cancer cell epithelial-to-mesenchymal transition.

a Total number of viable BC cells (Dapi⁻ cells by FACS) in co-culture with CAF-S1 (red) or CAF-S4 (blue) relative to control (− gray, without CAF) (n = 6 per BC cell type). b Total number of viable BC cells (Resazurin staining) with CAF-S1- or CAF-S4-conditioned medium (CM) relative to control (−, without CM) (n = 9 per BC cell type). c Total number of viable CAF-S1 (red) and CAF-S4 (blue) (Dapi⁻ cells by FACS) in co-culture with BC cells relative to control (−, without BC cells) (n ≥ 6 per BC cell type). d CAF-S1 and CAF-S4 capacities to attract BC cells (n ≥ 8 per BC cells). e Left, Images of co-staining of Vinculin (red), F-actin (green) and DAPI (blue) in MCF7 (left) or T47D (right) cultured alone, or in presence of CAF-S1 or CAF-S4. Scale bars, 20 μm; inset, 10 μm. Arrows show reduced BC cell cohesion in presence of CAF-S1/-S4; asterisks show F-actin interconnections between BC cells in presence of CAF-S4. Vinculin and F-actin individual staining in Supplementary Fig. 4c. Right, Number of BC cells per tumor area (at least 13 images per condition, n = 3 per BC cell type). f Left, Images of E-cadherin (red), F-actin (green) and DAPI (blue) co-staining (top) or of E-cadherin (red) and DAPI (blue) staining (bottom) in BC cells alone or in presence of CAF-S1/-S4. Scale bars, 20 μm; inset, 10 μm. Right, Quantification of E-cadherin staining per BC cell area (at least eight images per condition) (n = 2 per BC cell type). In all panels, barplots are mean ± SEM and n number of independent experiments; a. u., arbitrary units. a, d: p Values from Wilcoxon signed rank test. b, c: p Values from paired t-test. e right, f right: p Values from Student’s t-test (MCF7) and Mann–Whitney test (T47D). At least two CAF-S1 and CAF-S4 pairs tested, except in e, f for T47D, where one CAF-S1/-S4 pair is used. Source data provided in Source Data file, with R scripts used.