Given the reported paracrine effect of soluble factors secreted by breast cancer cells on breast stromal fibroblasts [19]—we assessed the effect of selected exogenous and paracrine growth factors (i.e., PDGF, bFGF, EGF, IGF-I and TGF-β) on the transcriptional regulation of decorin. This evidence concerns the gene TGFB1 and breast carcinoma.