TGFB1 and cancer: Human Cancer Associated Fibroblasts (hCAFs) are a heterogeneous population of fibroblasts originating from various sources of resident fibroblasts, including stellate cells, that are mainly activated by Transforming Growth Factor (TGF)-β1 and Platelet Derived Growth Factor (PDGF) that undergo the epithelial-to-mesenchymal transition (EMT), taking on a myofibroblast phenotype characterized by α-Smooth Muscle Actin (α-SMA) and Fibroblast Activation Protein (FAP) expression [13, 14].