Vascular endothelial growth factor receptor (VEGFR), Platelet-derived growth factor receptor (PDGFR), Fms-like tyrosine kinase 3 (FLT3), and KIT proto-oncogene receptor tyrosine kinase (KIT) (VEGFR/PDGFR/FLT3/KIT)

The target profile comprising Vascular Endothelial Growth Factor Receptor (VEGFR), Platelet-Derived Growth Factor Receptor (PDGFR), Fms-like tyrosine kinase 3 (FLT3), and KIT (c-Kit) represents a group of closely related receptor tyrosine kinases (RTKs) essential for vascular and hematological development (UniProt, 2024). VEGFR and PDGFR are primary drivers of angiogenesis and pericyte recruitment, respectively, which are vital for tumor neo-vascularization and maintenance (PubMed, PMID: 17067468). KIT and FLT3 are critical for the proliferation and differentiation of hematopoietic stem cells and are frequently mutated in leukemias and mesenchymal tumors (StatPearls, 2023). In oncology, these receptors are often co-targeted by multi-kinase inhibitors (MKIs) to achieve a synergistic effect by simultaneously inhibiting tumor cell proliferation and the supporting tumor microenvironment (NIH, 2023). While this multi-targeted approach is highly effective in diseases like renal cell carcinoma and gastrointestinal stromal tumors, it is also associated with a distinct profile of adverse effects, including cardiovascular and dermatological toxicities, due to the inhibition of these receptors in normal tissues (PubMed, PMID: 21810915). These receptors share a common structural feature: an intracellular split-kinase domain that is the primary binding site for small-molecule inhibitors (UniProt, 2024). Therapeutic intervention typically involves competitive inhibition of the ATP-binding pocket, which prevents the autophosphorylation required for downstream signal transduction (PubChem, 2024). Monitoring for specific mutations, such as FLT3-ITD or KIT exon 11, is often required to predict patient response to these therapies (NCCN, 2023).

Other names

Class III/IV/V receptor tyrosine kinasesSplit-kinase domain receptorsMulti-kinase inhibitor target profileAngiogenic receptor tyrosine kinases

Small-molecule inhibitors target the intracellular tyrosine kinase domain of these receptors, specifically competing with ATP for the binding site. This inhibition prevents receptor autophosphorylation and the subsequent activation of downstream signaling pathways, including the RAS/RAF/MEK/ERK and PI3K/AKT/mTOR cascades, thereby inhibiting cell proliferation, survival, and angiogenesis (PubChem, 2024; PubMed, PMID: 17067468).