Protein / target

ALK tyrosine kinase receptor

ALKQ9UM73Homo sapiensSwiss-Prot
Clinically validated
Therapeutic maturity
7
Approved medicines
30
Clinical trials
Small-molecule tractable
Druggability
Approved Drug

Protein at a glance

Biological role

Receptor signaling protein tyrosine kinase activator activity

Primary system

Nervous system

Strongest disease association

neuroblastoma

Genetic evidence · score 0.97

Therapeutic maturity

Clinically validated target

7 approved medicines against this target

Druggability

Small molecule

Open Targets tractability · Approved Drug

Clinical development

7 approved · 5 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

Neuronal receptor tyrosine kinase that is essentially and transiently expressed in specific regions of the central and peripheral nervous systems and plays an important role in the genesis and differentiation of the nervous system (PubMed:11121404, PubMed:11387242, PubMed:16317043, PubMed:17274988, PubMed:30061385, PubMed:34646012, PubMed:34819673). Also acts as a key thinness protein involved in the resistance to weight gain: in hypothalamic neurons, controls energy expenditure acting as a negative regulator of white adipose tissue lipolysis and sympathetic tone to fine-tune energy homeostasis (By similarity). Following activation by ALKAL2 ligand at the cell surface, transduces an extracellular signal into an intracellular response (PubMed:30061385, PubMed:33411331, PubMed:34646012, PubMed:34819673). In contrast, ALKAL1 is not a potent physiological ligand for ALK (PubMed:34646012). Ligand-binding to the extracellular domain induces tyrosine kinase activation, leading to activation of the mitogen-activated protein kinase (MAPK) pathway (PubMed:34819673). Phosphorylates almost exclusively at the first tyrosine of the Y-x-x-x-Y-Y motif (PubMed:15226403, PubMed:16878150). Induces tyrosine phosphorylation of CBL, FRS2, IRS1 and SHC1, as well as of the MAP kinases MAPK1/ERK2 and MAPK3/ERK1 (PubMed:15226403, PubMed:16878150). ALK activation may also be regulated by pleiotrophin (PTN) and midkine (MDK) (PubMed:11278720, PubMed:11809760, PubMed:12107166, PubMed:12122009). PTN-binding induces MAPK pathway activation, which is important for the anti-apoptotic signaling of PTN and regulation of cell proliferation (PubMed:11278720, PubMed:11809760, PubMed:12107166). MDK-binding induces phosphorylation of the ALK target insulin receptor substrate (IRS1), activates mitogen-activated protein kinases (MAPKs) and PI3-kinase, resulting also in cell proliferation induction (PubMed:12122009). Drives NF-kappa-B activation, probably through IRS1 and the activation of the AKT serine/threonine kinase (PubMed:15226403, PubMed:16878150). Recruitment of IRS1 to activated ALK and the activation of NF-kappa-B are essential for the autocrine growth and survival signaling of MDK (PubMed:15226403, PubMed:16878150). May function as regulator of gastric epithelial differentiation (By similarity)

Subcellular location

Cell membrane
Domains and Gene Ontology detail (26)

Domains & features

MAM 1LDL-receptor class AMAM 2Protein kinase

Gene Ontology

  • Cextracellular exosome
  • Cplasma membrane
  • Cprotein-containing complex
  • Creceptor complex
  • FATP binding
  • Fheparin binding
  • Fidentical protein binding
  • Fprotein tyrosine kinase activity
  • Freceptor signaling protein tyrosine kinase activator activity
  • Ftransmembrane receptor protein tyrosine kinase activity
  • Pcell surface receptor protein tyrosine kinase signaling pathway
  • Penergy homeostasis

1620 aa · 176 kDa

Biological roles

Reactome v97

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

Kinase signallingUniProt · GOApoptosis & cell deathGO
View supporting evidence

Kinase signalling

  • ·Neuronal receptor tyrosine kinase that is essentially and transiently expressed in speci…
  • ·protein tyrosine kinase activity
  • ·transmembrane receptor protein tyrosine kinase activity
  • ·peptidyl-tyrosine autophosphorylation

Apoptosis & cell death

  • ·regulation of apoptotic process
View underlying pathways (11)

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.

EML4PTNMDKNPM1KRASNRASPIK3CAPLCG1PIK3R1ALKAL2ALK

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.

lorlatinib
Narrow target profileApprovedInhibitor

ALK tyrosine kinase receptor inhibitor

Appears in clinical studies involving lymphoma, non-small cell lung carcinoma, non-small cell lung carcinoma, non-small cell lung carcinoma

Direct interaction with this protein · 1 of 2 recorded protein targets — narrow recorded profile

brigatinib
Narrow target profileApprovedInhibitor

ALK tyrosine kinase receptor inhibitor

Appears in clinical studies involving non-small cell lung carcinoma, anaplastic large cell lymphoma, non-small cell lung carcinoma, non-small cell lung carcinoma

Direct interaction with this protein · 1 of 2 recorded protein targets — narrow recorded profile

crizotinib
ApprovedInhibitor

ALK tyrosine kinase receptor inhibitor

Appears in clinical studies involving non-small cell lung carcinoma, non-small cell lung carcinoma, non-small cell lung carcinoma, neoplasm

Direct interaction with this protein · 1 of 6 recorded protein targets

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.

neuroblastoma0.97

Genetic · overall 0.84

neuroblastoma, susceptibility to, 30.86

Genetic · overall 0.76

cancer0.52

Genetic · overall 0.73

neoplasm0.28

Genetic · overall 0.66

Highest-confidence therapeutic associations

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

non-small cell lung carcinoma0.99

Clinical · overall 0.76

lung cancer0.71

Clinical · overall 0.54

anaplastic large cell lymphoma0.67

Clinical · overall 0.51

lymphoma0.67

Clinical · overall 0.47

lung adenocarcinoma0.49

Clinical · overall 0.49

Highest overall evidence

Remaining associations by Open Targets' aggregated evidence score.

squamous cell lung carcinoma0.47

Somatic mutation

Show all associations
neuroblastoma0.84
neuroblastoma, susceptibility to, 30.76
non-small cell lung carcinoma0.76
cancer0.73
neoplasm0.66
lung cancer0.54
anaplastic large cell lymphoma0.51
lung adenocarcinoma0.49
squamous cell lung carcinoma0.47
lymphoma0.47

Open Targets ranks 1,443 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 · 12 total

LORLATINIBApproval

lymphoma · non-small cell lung carcinoma · non-small cell lung carcinoma

PLB1003Phase 1

non-small cell lung carcinoma

ALECTINIB HYDROCHLORIDEApproval

non-small cell lung carcinoma · non-small cell lung carcinoma

BRIGATINIBApproval

non-small cell lung carcinoma · anaplastic large cell lymphoma · non-small cell lung carcinoma

CRIZOTINIBApproval

non-small cell lung carcinoma · non-small cell lung carcinoma · non-small cell lung carcinoma

ENSARTINIBPhase 3

non-small cell lung carcinoma · non-small cell lung carcinoma · non-Hodgkin lymphoma

ASP-3026Phase 1

diffuse large B-cell lymphoma · non-small cell lung carcinoma · neuroblastoma

CONTELTINIBPhase 1 2

malignant pancreatic neoplasm · non-small cell lung carcinoma

ENTRECTINIBApproval

non-small cell lung carcinoma · non-small cell lung carcinoma · neoplasm

CEP-37440Phase 1

neoplasm

Tractability

SM · Approved DrugSM · Structure with LigandSM · High-Quality LigandSM · High-Quality PocketSM · Druggable FamilyAB · UniProt loc high confAB · GO CC high confAB · UniProt SigP or TMHMMAB · Human Protein Atlas locPR · LiteraturePR · Database UbiquitinationPR · Small Molecule Binder

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)

ACTIVE_NOT_RECRUITING · via crizotinib · NCT02465060

ACTIVE_NOT_RECRUITING · via crizotinib · NCT06357975

ClinicalTrials.gov via the drug-target graph.

Related literature

7

Papers indexed under “Anaplastic Lymphoma Kinase” — a subject heading that covers this protein without being specific to it. Shown as context; not counted as this protein's own research activity.

Lorlatinib Versus Crizotinib in Patients With Advanced <i>ALK</i>-Positive Non-Small Cell Lung Cancer: 5-Year Outcomes From the Phase III CROWN Study.

Solomon BJ · Journal of clinical oncology : official journal of the American Society of Clinical Oncology · 2024

Brigatinib Versus Crizotinib in ALK Inhibitor-Naive Advanced ALK-Positive NSCLC: Final Results of Phase 3 ALTA-1L Trial.

Camidge DR · Journal of thoracic oncology : official publication of the International Association for the Study of Lung Cancer · 2021

Alterations in ALK/ROS1/NTRK/MET drive a group of infantile hemispheric gliomas.

Guerreiro Stucklin AS · Nature communications · 2019

Atezolizumab for First-Line Treatment of Metastatic Nonsquamous NSCLC.

Socinski MA · The New England journal of medicine · 2018

First-line crizotinib versus chemotherapy in ALK-positive lung cancer.

Solomon BJ · The New England journal of medicine · 2014

ROS1 rearrangements define a unique molecular class of lung cancers.

Bergethon K · Journal of clinical oncology : official journal of the American Society of Clinical Oncology · 2012

Clinical features and outcome of patients with non-small-cell lung cancer who harbor EML4-ALK.

Shaw AT · Journal of clinical oncology : official journal of the American Society of Clinical Oncology · 2009

Europe PMC literature, reached through a MeSH descriptor linked to this protein.

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.

neuroblastomaWell supported
0.99
agreement 0.911.00
Genetic46%Somatic mutation24%Clinical17%Literature7%Pathway6%Genetic literaturedup

Open Targets aggregate 0.84 · 5 independent evidence families · 1 not counted as duplicate

neuroblastoma, susceptibility to, 3Well supported
0.94
agreement 0.831.00
Genetic60%Somatic mutation40%Genetic literaturedup

Open Targets aggregate 0.76 · 2 independent evidence families · 1 not counted as duplicate

non-small cell lung carcinomaWell supported
0.92
agreement 0.811.00
Clinical45%Somatic mutation24%Pathway22%Literature9%

Open Targets aggregate 0.76 · 4 independent evidence families

neoplasmWell supported
0.87
agreement 0.780.96
Clinical49%Somatic mutation21%Genetic20%Literature10%

Open Targets aggregate 0.66 · 4 independent evidence families

cancerWell supported
0.86
agreement 0.770.96
Genetic35%Clinical31%Pathway26%Literature10%

Open Targets aggregate 0.73 · 4 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

8

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 publication2024-05-31
    Lorlatinib Versus Crizotinib in Patients With Advanced <i>ALK</i>-Positive Non-Small Cell Lung Cancer: 5-Year Outcomes From the Phase III CROWN Study.

    Journal of clinical oncology : official journal of the American Society of Clinical Oncology · 2024 · 254 citations · Europe PMC · via lorlatinib

  2. New publication2021-09-16
    Brigatinib Versus Crizotinib in ALK Inhibitor-Naive Advanced ALK-Positive NSCLC: Final Results of Phase 3 ALTA-1L Trial.

    Journal of thoracic oncology : official publication of the International Association for the Study of Lung Cancer · 2021 · 300 citations · Europe PMC · via brigatinib

  3. Regulatory approval2019-05-06

    Approval: Lorviqua (EMA)

    ema · regulatory · ema · via lorlatinib

  4. Regulatory approval2018-11-22

    Approval: Alunbrig (EMA)

    ema · regulatory · ema · via brigatinib

  5. Safety communication2015-11-12

    Drug Safety Update: Crizotinib (Xalkori▼): risk of cardiac failure

    mhra · safety · mhra · via crizotinib

  6. New publication2014-12-01
    First-line crizotinib versus chemotherapy in ALK-positive lung cancer.

    The New England journal of medicine · 2014 · 2,470 citations · Europe PMC · via crizotinib

  7. Regulatory approval2012-10-23

    Approval: Xalkori (EMA)

    ema · regulatory · ema · via crizotinib

  8. New publication2012-01-03
    ROS1 rearrangements define a unique molecular class of lung cancers.

    Journal of clinical oncology : official journal of the American Society of Clinical Oncology · 2012 · 1,121 citations · Europe PMC · via crizotinib

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.