Pancreatic stellate cell: Pandora's box for pancreatic disease biology

Figure 3 Autocrine and paracrine factors mediating pancreatic stellate cell activation. Cytokines and growth factors secreted by injured acinar cells, immune cells and cancer cells activate the pancreatic stellate cells (PSCs) in a paracrine fashion and stimulate them to secrete various factors. These factors secreted by PSCs in turn acts in a paracrine fashion and sustains its activation. This autocrine and paracrine signal cycles may help PSCs to retain its activated phenotype, resulting in excess ECM deposition, culminating to pancreatic fibrosis. ROS: Reactive oxygen species; PC: Pancreatic cancer; FGF: Fibroblast growth factor; PDGF: Platelet derived growth factor; TGF-β: Transforming growth factor-β; VEGF: Vascular endothelial growth factor; TNF-α: tumor necrosis factor-α; MMP: Matrix metalloproteinase; CP: Chronic Pancreatitis; TIMPs: Tissue inhibitors of matrix metalloproteinases; CTGF: Connective tissue growth factor; IL: Interleukin.