Protein / target

Mast/stem cell growth factor receptor Kit

KITP10721Homo sapiensSwiss-Prot
Clinically validated
Therapeutic maturity
20
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

Nervous system

Strongest disease association

cutaneous mastocytosis

Genetic evidence · score 0.92

Therapeutic maturity

Clinically validated target

20 approved medicines against this target

Druggability

Small molecule

Open Targets tractability · Approved Drug

Clinical development

20 approved · 18 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 the cytokine KITLG/SCF and plays an essential role in the regulation of cell survival and proliferation, hematopoiesis, stem cell maintenance, gametogenesis, mast cell development, migration and function, and in melanogenesis. In response to KITLG/SCF binding, KIT can activate several signaling pathways. Phosphorylates PIK3R1, PLCG1, SH2B2/APS and CBL. Activates the AKT1 signaling pathway by phosphorylation of PIK3R1, the regulatory subunit of phosphatidylinositol 3-kinase. Activated KIT also transmits signals via GRB2 and activation of RAS, RAF1 and the MAP kinases MAPK1/ERK2 and/or MAPK3/ERK1. Promotes activation of STAT family members STAT1, STAT3, STAT5A and STAT5B. Activation of PLCG1 leads to the production of the cellular signaling molecules diacylglycerol and inositol 1,4,5-trisphosphate. KIT signaling is modulated by protein phosphatases, and by rapid internalization and degradation of the receptor. Activated KIT promotes phosphorylation of the protein phosphatases PTPN6/SHP-1 and PTPRU, and of the transcription factors STAT1, STAT3, STAT5A and STAT5B. Promotes phosphorylation of PIK3R1, CBL, CRK (isoform Crk-II), LYN, MAPK1/ERK2 and/or MAPK3/ERK1, PLCG1, SRC and SHC1

Subcellular location

Cell membraneCytoplasm
Domains and Gene Ontology detail (80)

Domains & features

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

Gene Ontology

  • Cacrosomal vesicle
  • Ccell-cell junction
  • Ccytoplasmic side of plasma membrane
  • Cexternal side of plasma membrane
  • Cextracellular space
  • Cplasma membrane
  • Creceptor complex
  • FATP binding
  • Fcytokine binding
  • Fgrowth factor binding
  • Fmetal ion binding
  • Fprotease binding

976 aa · 110 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 · GOImmune signallingUniProt · GOTranscriptional regulationUniProt · ReactomeMuscle contractionGOCell adhesionGOProteolysisGO
View supporting evidence

Kinase signalling

  • ·Tyrosine-protein kinase that acts as a cell-surface receptor for the cytokine KITLG/SCF…
  • ·protein tyrosine kinase activity
  • ·transmembrane receptor protein tyrosine kinase activity
  • ·positive regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction

Immune signalling

  • ·Tyrosine-protein kinase that acts as a cell-surface receptor for the cytokine KITLG/SCF…
  • ·cytokine binding
  • ·B cell differentiation
  • ·cytokine-mediated signaling pathway

Transcriptional regulation

  • ·Tyrosine-protein kinase that acts as a cell-surface receptor for the cytokine KITLG/SCF…
  • ·TFAP2 (AP-2) family regulates transcription of growth factors and their receptors
  • ·Transcriptional and post-translational regulation of MITF-M expression and activity

Muscle contraction

  • ·positive regulation of colon smooth muscle contraction
  • ·positive regulation of pyloric antrum smooth muscle contraction
  • ·positive regulation of small intestine smooth muscle contraction

Cell adhesion

  • ·cell-cell junction

Proteolysis

  • ·protease binding
View underlying pathways (22)

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.

KITLGGRB2PIK3R1CLEC11APTPN11PIK3CANRASKRASCXCL12EGFKIT

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

4

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.

pexidartinib
Narrow target profileApprovedInhibitor

Stem cell growth factor receptor inhibitor

Appears in clinical studies involving tenosynovial giant cell tumor, diffuse type, neoplasm, Alzheimer disease, pigmented villonodular synovitis

Direct interaction with this protein · 1 of 3 recorded protein targets — narrow recorded profile

Imatinib Mesylate
ApprovedInhibitor

Stem cell growth factor receptor inhibitor

Appears in clinical studies involving chronic myelogenous leukemia, BCR-ABL1 positive, myelodysplastic/myeloproliferative disease, gastrointestinal stromal tumor, dermatofibrosarcoma protuberans

Direct interaction with this protein · 1 of 4 recorded protein targets

sunitinib
ApprovedInhibitor

Stem cell growth factor receptor 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

regorafenib
ApprovedInhibitor

Stem cell growth factor receptor inhibitor

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

Direct interaction with this protein · 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.

cutaneous mastocytosis0.92

Genetic · overall 0.81

piebaldism0.91

Genetic · overall 0.82

gastrointestinal stromal tumor0.91

Genetic · overall 0.89

mastocytosis0.67

Genetic · overall 0.66

acute myeloid leukemia0.61

Genetic literature · overall 0.74

Highest-confidence therapeutic associations

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

chronic myelogenous leukemia, BCR-ABL1 positive0.99

Clinical · overall 0.70

hepatocellular carcinoma0.97

Clinical · overall 0.67

neoplasm0.96

Clinical · overall 0.63

systemic mastocytosis0.85

Clinical · overall 0.63

cancer0.19

Clinical · overall 0.66

Show all associations
gastrointestinal stromal tumor0.89
piebaldism0.82
cutaneous mastocytosis0.81
acute myeloid leukemia0.74
chronic myelogenous leukemia, BCR-ABL1 positive0.70
hepatocellular carcinoma0.67
mastocytosis0.66
cancer0.66
systemic mastocytosis0.63
neoplasm0.63

Open Targets ranks 2,858 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 · 38 total

SEMAXANIBPhase 3

colorectal cancer · Kaposi's sarcoma · soft tissue sarcoma

SORAFENIBApproval

renal cell carcinoma · hepatocellular carcinoma · renal cell carcinoma

XL-820Phase 2

gastrointestinal stromal tumor

DOVITINIBPhase 3

renal cell carcinoma · endometrial cancer · triple-negative breast carcinoma

PEXIDARTINIB HYDROCHLORIDEApproval

tenosynovial giant cell tumor

SORAFENIB TOSYLATEApproval

renal cell carcinoma · thyroid gland carcinoma · hepatocellular carcinoma

TELATINIBPhase 2

gastric adenocarcinoma · gastric cancer · gastroesophageal junction adenocarcinoma

RIPRETINIBApproval

gastrointestinal stromal tumor · gastrointestinal stromal tumor · neoplasm

AVAPRITINIBApproval

gastrointestinal stromal tumor · gastrointestinal stromal tumor · neoplasm

SERALUTINIBPhase 3

pulmonary arterial hypertension · pulmonary hypertension

Tractability

SM · Approved DrugSM · Structure with LigandSM · High-Quality LigandSM · High-Quality PocketSM · Druggable FamilyAB · Phase 1 ClinicalAB · GO CC high confAB · UniProt loc med confAB · UniProt SigP or TMHMMAB · Human Protein Atlas locPR · LiteraturePR · UniProt Ubiquitination

Safety liabilities

mastocytosisAnaemianeutropeniahaematotoxicityneovascularizationheart diseasethrombocytopeniarashcardiac disorderCarcinogenicity

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.

gastrointestinal stromal tumorWell supported
0.99
agreement 0.911.00
Genetic32%Clinical26%Somatic mutation18%Pathway13%Animal model7%Literature5%Genetic literaturedup

Open Targets aggregate 0.89 · 6 independent evidence families · 1 not counted as duplicate

cutaneous mastocytosisWell supported
0.98
agreement 0.891.00
Genetic46%Somatic mutation22%Clinical16%Animal model13%Literature4%Genetic literaturedup

Open Targets aggregate 0.81 · 5 independent evidence families · 1 not counted as duplicate

acute myeloid leukemiaWell supported
0.96
agreement 0.871.00
Clinical30%Genetic literature21%Somatic mutation18%Pathway14%Animal model11%Literature6%Geneticdup

Open Targets aggregate 0.74 · 6 independent evidence families · 1 not counted as duplicate

piebaldismWell supported
0.93
agreement 0.811.00
Genetic80%Animal model20%Literature1%Genetic literaturedup

Open Targets aggregate 0.82 · 3 independent evidence families · 1 not counted as duplicate

mastocytosisWell supported
0.92
agreement 0.831.00
Genetic39%Clinical34%Somatic mutation20%Literature7%Genetic literaturedup

Open Targets aggregate 0.66 · 4 independent evidence families · 1 not counted as duplicate

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

60

Recent activity around this target, drawn from one canonical event stream. Every item is reached through 4 drugs that target this protein, so each event is news about that drug rather than about the protein directly.

  1. Label change2026-07-13

    Label change: IMATINIB MESYLATE (NDA021588)

    fda · regulatory · fda · via Imatinib Mesylate

  2. Label change2026-01-14

    Label change: IMATINIB MESYLATE (NDA021588)

    fda · regulatory · fda · via Imatinib Mesylate

  3. New publication2025-04-30
    Brain-wide microglia replacement using a nonconditioning strategy ameliorates pathology in mouse models of neurological disorders.

    Science translational medicine · 2025 · 11 citations · Europe PMC · via pexidartinib

  4. 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

  5. Label change2024-12-09

    Label change: IMATINIB (ANDA204644)

    fda · regulatory · fda · via Imatinib Mesylate

  6. 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

  7. 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

  8. Supplemental approval2024-03-01

    Supplemental approval: IMATINIB MESYLATE (NDA021588)

    fda · regulatory · fda · via Imatinib Mesylate

  9. New publication2024-02-27
    KIT mutations and expression: current knowledge and new insights for overcoming IM resistance in GIST.

    Cell communication and signaling : CCS · 2024 · 28 citations · Europe PMC · via Imatinib Mesylate

  10. Label change2024-01-05

    Label change: IMATINIB (ANDA204644)

    fda · regulatory · fda · via Imatinib Mesylate

  11. Label change2024-01-05

    Label change: IMATINIB (ANDA204644)

    fda · regulatory · fda · via Imatinib Mesylate

  12. Label change2024-01-05

    Label change: IMATINIB (ANDA204644)

    fda · regulatory · fda · via Imatinib Mesylate

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.