Figure 7. CTGF-fibroblasts greatly decrease the expression of ATPase-IF1 in adjacent MDA-MB-231 cells. To verify if CTGF-fibroblasts exert any paracrine effects on tumor cells, GFP-positive MDA-MB-231 cells were co-cultured with CTGF-fibroblasts or control fibroblasts for 3 d. Cells were then immuno-stained with antibodies against ATPase-IF1 (an endogenous inhibitor of the mitochondrial ATP synthase, RED). Nuclei were stained with DAPI (BLUE). Note that fibroblasts overexpressing CTGF reduce the levels of ATPase-IF in adjacent MDA-MB-231 cells (GFP). The white stars mark the nuclei of MDA-MB-231 cells.These results indicate that CTGF-fibroblasts increase the mitochondrial activity in adjacent breast cancer cells, by reducing ATPase-IF expression.