VEGFR and PDGFR

Vascular endothelial growth factor receptors (VEGFRs) and platelet-derived growth factor receptors (PDGFRs) are families of cell surface receptor tyrosine kinases involved in the regulation of angiogenesis, vascular development, cell proliferation, and migration. VEGFRs consist of three main types (VEGFR1/Flt-1, VEGFR2/KDR/Flk-1, VEGFR3/Flt-4), with VEGFR2/KDR being the principal mediator of VEGF-driven angiogenic signaling in endothelial cells, while PDGFRs have two main subtypes (PDGFRα and PDGFRβ) essential for development and tissue repair. Therapeutic agents targeting these receptors are used for the treatment of cancer and other diseases characterized by abnormal angiogenesis or cell proliferation, but they pose safety challenges due to the central role of these receptors in normal vascular homeostasis and function. While VEGFRs and PDGFRs share structural similarities—including a split tyrosine kinase domain and immunoglobulin-like extracellular domains—they mediate distinct ligand-dependent cellular functions. There is also evidence for cross-talk between these receptor families in certain disease contexts.

Other names

VEGFR: kinase insert domain receptor (KDR; commonly refers to VEGFR2)fetal liver kinase 1 (Flk-1, mouse homolog)Flt-1 (VEGFR1)Flt-4 (VEGFR3)PDGFR: PDGFR alpha (PDGFRα)PDGFR beta (PDGFRβ)

Inhibition of kinase activity (prevents phosphorylation); Ligand blocking (prevents VEGF or PDGF from activating their receptors); Downregulation of downstream signaling such as MAPK, PI3K/Akt, PLCγ, Bcl-2