Protein / target

Vascular endothelial growth factor receptor 3

FLT4P35916Homo sapiensSwiss-Prot
Clinically validated
Therapeutic maturity
18
Approved medicines
30
Clinical trials
Small-molecule tractable
Druggability
Approved Drug

Protein at a glance

Biological role

Transmembrane receptor protein tyrosine kinase activity

Primary system

Cardiovascular system

Strongest disease association

lymphatic malformation 1

Genetic evidence · score 0.95

Therapeutic maturity

Clinically validated target

18 approved medicines against this target

Druggability

Small molecule

Open Targets tractability · Approved Drug

Clinical development

18 approved · 28 in clinical development

30 linked trials

Derived from structured UniProt, Open Targets and literature data on this page.

Protein profile

UniProt 2026_02

Canonical identity and biological annotation from UniProt.

Function

Tyrosine-protein kinase that acts as a cell-surface receptor for VEGFC and VEGFD, and plays an essential role in adult lymphangiogenesis and in the development of the vascular network and the cardiovascular system during embryonic development. Promotes proliferation, survival and migration of endothelial cells, and regulates angiogenic sprouting. Signaling by activated FLT4 leads to enhanced production of VEGFC, and to a lesser degree VEGFA, thereby creating a positive feedback loop that enhances FLT4 signaling. Modulates KDR signaling by forming heterodimers. The secreted isoform 3 may function as a decoy receptor for VEGFC and/or VEGFD and play an important role as a negative regulator of VEGFC-mediated lymphangiogenesis and angiogenesis. Binding of vascular growth factors to isoform 1 or isoform 2 leads to the activation of several signaling cascades; isoform 2 seems to be less efficient in signal transduction, because it has a truncated C-terminus and therefore lacks several phosphorylation sites. Mediates activation of the MAPK1/ERK2, MAPK3/ERK1 signaling pathway, of MAPK8 and the JUN signaling pathway, and of the AKT1 signaling pathway. Phosphorylates SHC1. Mediates phosphorylation of PIK3R1, the regulatory subunit of phosphatidylinositol 3-kinase. Promotes phosphorylation of MAPK8 at 'Thr-183' and 'Tyr-185', and of AKT1 at 'Ser-473'

Subcellular location

Cell membraneCytoplasmNucleusSecreted
Domains and Gene Ontology detail (42)

Domains & features

Ig-like C2-type 1Ig-like C2-type 2Ig-like C2-type 3Ig-like C2-type 4Ig-like C2-type 5Ig-like C2-type 6Ig-like C2-type 7Protein kinase

Gene Ontology

  • Ccytosol
  • Cextracellular region
  • Cnucleus
  • Cplasma membrane
  • Creceptor complex
  • FATP binding
  • Fgrowth factor binding
  • Fprotein homodimerization activity
  • Fprotein phosphatase binding
  • Ftransmembrane receptor protein tyrosine kinase activity
  • Fvascular endothelial growth factor receptor activity
  • Pblood vessel morphogenesis

1363 aa · 153 kDa · 3 isoforms

Biological roles

Reactome v97

What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.

Kinase signallingUniProt · GOTranscriptional regulationReactomeApoptosis & cell deathGO
View supporting evidence

Kinase signalling

  • ·Tyrosine-protein kinase that acts as a cell-surface receptor for VEGFC and VEGFD, and pl…
  • ·transmembrane receptor protein tyrosine kinase activity
  • ·peptidyl-tyrosine phosphorylation
  • ·positive regulation of protein phosphorylation

Transcriptional regulation

  • ·NOTCH4 Intracellular Domain Regulates Transcription

Apoptosis & cell death

  • ·negative regulation of apoptotic process
View underlying pathways (3)

Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.

Interaction neighbourhood

STRING v12.0

Proteins with the strongest functional or physical association. Node size and line weight reflect STRING confidence; hover or select a partner to inspect one association.

VEGFCVEGFBVEGFDPGFKDRNRP2PDGFCANGPT2GRB2SHC1FLT4

10 strongest partners — larger node and heavier line mean higher confidence

Functional and physical associations from STRING v12.0. Only associations with this protein are drawn — partner-to-partner links are not part of this evidence.

Drugs targeting this protein

3

Whether each drug engages this protein directly or through a complex, and how many other targets are recorded for it. Direct binders with few recorded targets are listed first.

sunitinib
ApprovedInhibitor

Vascular endothelial growth factor receptor 3 inhibitor

Appears in clinical studies involving gastrointestinal stromal tumor, renal cell carcinoma, gastrointestinal stromal tumor, neuroendocrine neoplasm

Direct interaction with this protein · 1 of 9 recorded protein targets — broad pharmacology

axitinib
ApprovedInhibitor

Vascular endothelial growth factor receptor inhibitor

Appears in clinical studies involving renal cell carcinoma, renal cell carcinoma, neoplasm, pancreatic adenocarcinoma

Acts on a complex — shared with FLT1, KDR · 1 of 3 recorded protein targets — narrow recorded profile

regorafenib
ApprovedInhibitor

Vascular endothelial growth factor receptor inhibitor

Appears in clinical studies involving colorectal cancer, metastatic colorectal cancer, colorectal neoplasm, neoplasm

Acts on a complex — shared with FLT1, KDR · 1 of 18 recorded protein targets — broad pharmacology

ChEMBL mechanism, action type and target identity. Open Targets clinical status and indications.

Translational evidence

Open Targets 26

Why this target matters therapeutically — disease associations, drugs in development, tractability and safety, from Open Targets.

Strongest genetic associations

Human genetic evidence — the most direct causal link between this target and a disease.

lymphatic malformation 10.95

Genetic · overall 0.78

congenital heart defects, multiple types, 70.89

Genetic · overall 0.77

Milroy disease0.85

Genetic · overall 0.75

capillary infantile hemangioma0.71

Genetic · overall 0.63

neoplasm0.19

Genetic · overall 0.62

Highest-confidence therapeutic associations

Diseases where a drug acting on this target has already reached clinical development.

renal cell carcinoma0.99

Clinical · overall 0.61

hepatocellular carcinoma0.98

Clinical · overall 0.68

gastrointestinal stromal tumor0.96

Clinical · overall 0.65

non-small cell lung carcinoma0.89

Clinical · overall 0.64

thyroid gland carcinoma0.88

Clinical · overall 0.60

Show all associations
lymphatic malformation 10.78
congenital heart defects, multiple types, 70.77
Milroy disease0.75
hepatocellular carcinoma0.68
gastrointestinal stromal tumor0.65
non-small cell lung carcinoma0.64
capillary infantile hemangioma0.63
neoplasm0.62
renal cell carcinoma0.61
thyroid gland carcinoma0.60

Open Targets ranks 980 associations for this target and we store the top 10 by aggregated score. The long tail is largely literature co-mention and RNA-expression evidence, not evidence that this target drives those diseases.

Known drugs · 47 total

OSI-930Phase 1
TIVOZANIBApproval

renal cell carcinoma · neoplasm · renal cell adenocarcinoma

JNJ-26483327Phase 1
CATEQUENTINIBPhase 3

alveolar soft part sarcoma · leiomyosarcoma · synovial sarcoma

IBCASERTIBPhase 3

small cell lung carcinoma · cancer · ovarian cancer

TELATINIBPhase 2

gastric adenocarcinoma · gastric cancer · gastroesophageal junction adenocarcinoma

SUNITINIBApproval

gastrointestinal stromal tumor · renal cell carcinoma · gastrointestinal stromal tumor

XL-820Phase 2

gastrointestinal stromal tumor

BRIVANIBPhase 3

breast cancer · liver cancer · hepatocellular carcinoma

SORAFENIBApproval

renal cell carcinoma · hepatocellular carcinoma · renal cell carcinoma

Tractability

SM · Approved DrugSM · High-Quality LigandSM · Druggable FamilyAB · Phase 1 ClinicalAB · UniProt loc high confAB · GO CC high confAB · UniProt loc med confAB · UniProt SigP or TMHMMPR · Database UbiquitinationPR · Small Molecule Binder

Safety liabilities

regulation of catalytic activityheart disease

Clinical trials

30

Trials of drugs that target this protein — reached indirectly through those drugs, so a trial listed here studies the drug, not the protein.

Show remaining trials (24)

COMPLETED · via sunitinib · NCT00357318

ClinicalTrials.gov via the drug-target graph.

Forefront confidence

Synthesis

Our own weighting of the evidence behind each disease association. Human genetics and clinical evidence count for most; literature co-mention counts for little, because two entities sharing an abstract is not evidence that one drives the other.

lymphatic malformation 1Well supported
0.96
agreement 0.841.00
Genetic82%Animal model17%Literature1%Genetic literaturedup

Open Targets aggregate 0.78 · 3 independent evidence families · 1 not counted as duplicate

congenital heart defects, multiple types, 7Well supported
0.93
agreement 0.821.00
Genetic71%Somatic mutation28%Literature0%Genetic literaturedup

Open Targets aggregate 0.77 · 3 independent evidence families · 1 not counted as duplicate

Milroy diseaseWell supported
0.89
agreement 0.771.00
Genetic75%Animal model21%Literature4%Genetic literaturedup

Open Targets aggregate 0.75 · 3 independent evidence families · 1 not counted as duplicate

capillary infantile hemangiomaWell supported
0.86
agreement 0.760.96
Genetic55%Somatic mutation27%Animal model18%Genetic literaturedup

Open Targets aggregate 0.63 · 3 independent evidence families · 1 not counted as duplicate

non-small cell lung carcinomaWell supported
0.82
agreement 0.700.94
Clinical58%Somatic mutation34%Literature8%

Open Targets aggregate 0.64 · 3 independent evidence families

The evidence agreement range shows how closely the independent evidence families agree — it is not a statistical confidence interval, and nothing here is fitted to outcome data. Derived from Open Targets evidence types under Forefront weighting; the underlying per-type scores are shown above so the calculation can be checked.

What's happening now

34

Recent activity around this target, drawn from one canonical event stream. Every item is reached through 3 drugs that target this protein, so each event is news about that drug rather than about the protein directly.

  1. New publication2026-01-28
    Fecal microbiota transplantation plus pembrolizumab and axitinib in metastatic renal cell carcinoma: the randomized phase 2 TACITO trial.

    Nature medicine · 2026 · 8 citations · Europe PMC · via axitinib

  2. New publication2025-01-06
    Efficacy of pembrolizumab in microsatellite-stable, tumor mutational burden-high metastatic colorectal cancer: genomic signatures and clinical outcomes.

    ESMO open · 2025 · 10 citations · Europe PMC · via regorafenib

  3. Regulatory approval2024-09-19

    Approval: Axitinib Accord (EMA)

    ema · regulatory · ema · via axitinib

  4. New publication2024-06-04
    Lenvatinib Plus Pembrolizumab Versus Standard of Care for Previously Treated Metastatic Colorectal Cancer: Final Analysis of the Randomized, Open-Label, Phase III LEAP-017 Study.

    Journal of clinical oncology : official journal of the American Society of Clinical Oncology · 2024 · 69 citations · Europe PMC · via regorafenib

  5. New publication2024-05-03
    Machine-learning and mechanistic modeling of metastatic breast cancer after neoadjuvant treatment.

    PLoS computational biology · 2024 · 10 citations · Europe PMC · via sunitinib

  6. New publication2024-03-15
    The more the merrier? Evidence and efficacy of immune checkpoint- and tyrosine kinase inhibitor combinations in advanced solid cancers.

    Cancer treatment reviews · 2024 · 17 citations · Europe PMC · via axitinib

  7. New publication2024-01-05
    Genomic profiling in GIST: Implications in clinical outcome and future challenges.

    Neoplasia (New York, N.Y.) · 2024 · 20 citations · Europe PMC · via sunitinib

  8. New publication2021-03-01
    Nivolumab plus Cabozantinib versus Sunitinib for Advanced Renal-Cell Carcinoma.

    The New England journal of medicine · 2021 · 1,297 citations · Europe PMC · via sunitinib

  9. Regulatory approval2021-02-11

    Approval: Sunitinib Accord (EMA)

    ema · regulatory · ema · via sunitinib

  10. New publication2020-08-11
    Targeted therapy for hepatocellular carcinoma.

    Signal transduction and targeted therapy · 2020 · 565 citations · Europe PMC · via regorafenib

  11. New publication2020-06-21
    Liver transarterial chemoembolization and sunitinib for unresectable hepatocellular carcinoma: Results of the PRODIGE 16 study.

    Clinics and research in hepatology and gastroenterology · 2021 · 15 citations · Europe PMC · via sunitinib

  12. New publication2020-04-25
    Updated efficacy results from the JAVELIN Renal 101 trial: first-line avelumab plus axitinib versus sunitinib in patients with advanced renal cell carcinoma.

    Annals of oncology : official journal of the European Society for Medical Oncology · 2020 · 319 citations · Europe PMC · via axitinib

Objective event titles are shown unmodified; the event kind and significance line are derived from structured fields. Forefront AttentionEvent stream aggregating Europe PMC Regulatory filings ClinicalTrials.gov.