PDGFB encodes platelet-derived growth factor subunit B, a potent mitogen essential for mesenchymal cell proliferation, migration, and survival 1. PDGFB functions as a critical developmental regulator, required for normal pericyte and vascular smooth muscle cell recruitment in the central nervous system, skin, lung, heart, and placenta, as well as for blood vessel development and kidney glomeruli formation [UniProt]. Mechanistically, PDGFB signals through PDGFRβ to activate MAPK/ERK, PI3K/AKT, and JAK/STAT3 pathways 2, and can stimulate mTORC1 signaling in cancer cells 3. In vascular biology, PDGF-BB recruits pericytes to endothelial sprouts, limiting angiogenic sprouting while stabilizing vessels 4. Clinically, PDGFB is overexpressed in multiple malignancies including breast cancer and colon adenocarcinoma, where it promotes angiogenesis and lymphangiogenesis 5, and contributes to tumor progression 2. PDGFB antagonism combined with VEGF inhibitors shows therapeutic benefit in ocular neovascular diseases 6. Heterozygous PDGFB mutations cause primary familial brain calcification (PFBC), an autosomal dominant disorder characterized by basal ganglia calcifications, movement disorders, and cognitive decline, suggesting disrupted phosphate homeostasis as a pathophysiological mechanism 7.