Fig. 4

Induction of angiogenesis. Representative pictures of tube formation assay wells for all conditions (magnification × 20). Tube formation could be detected after incubation of HUVECs with conditioned media from co-cultured ADSCs-BRCAs as well as from ADSC and BRCA (primary and cell lines) monoculture. The co-culture of ADSCs and BRCAs led to an increase in angiogenic properties in both ADSCs and BRCAs for all cell lines. For ADSCs, a strong increase in angiogenesis could be seen in co-culture with MCF-7 and primary BRCAs, a moderate increase in co-culture with MDA-MB-231, and a slight increase in co-culture with SK-BR-3 and ZR-75-30. Co-culture with EVSA-T did not change the induction of angiogenesis. For BRCAs, a strong increase in the angiogenic properties in co-culture with ADSCs was found for MCF-7, MDA-MB-231, and SK-BR-3 cells, a moderate increase for ZR-75-30, and slight increase for EVSA-T. We could not detect a significant influence of co-culture on primary BRCAs. ADSC adipose-derived mesenchymal stem cell