Fig. 1

Breast cancer cells promote adipocyte-derived collagen I reorganization in vitro. a The morphology and bodipy staining of adipocytes alone or cocultured with MDA-MB-231 or SKBR-3 cells. b Relative mRNA expression of adipogenic markers, including AP2, C/EBPα and PPARɣ in adipocytes cultured alone or cocultivated with different breast tumor cells (MDA-MB-231, BT-474 or SKBR-3 cells). c Relative mRNA expression of fibroblastic markers, including FSP-1 and α-SMA in adipocytes cultured alone or cocultivated with different breast tumor cells (MDA-MB-231, BT-474 or SKBR-3 cells). d-e A representative picture of spheroid invasion in a collagen matrix ((left), scale bar: 50 μm, and measurement of the relative invasion capacity at indicated time points (right)). Bars and errors flags represent the means ± SD of three independent experiments, ^* indicated adipocytes-derived collagen matrix compared to collagen gel alone at the same time point, ^# indicated CAAs- embedded collagen matrix compared with adipocytes- embedded collagen matrix at the same time point. f 3 T3-L1 mature adipocytes were grown on coverslips and cultivated in the presence (co-culture) or in the absence (control) of MDA-MB-231 cells for 72 h. After this period, cells were fixed and stained with Collagen I (green) and DAPI (blue). 3 T3-L1 pre - adipocytes served as a control. g Photographs showing collagen I matrix (1 mg/ml) contracted in the presence of either adipocytes, CAAs or breast cancer cells. h Phase contrast image of GFP-tagged MDA-MB-231 cells, which were either plated on ECM derived from adipocytes or CAAs was shown, the elliptical factor (length/breadth ratio) was calculated for MDA-MB-231 cells plated on ECM derived from adipocytes or CAAs. Bars and errors flags represent the means ± SD of three independent experiments that were classified as statistically significant using student’s t test. Scale bar, 100 μm. ***p < 0.0001versus adipocytes derived ECM