Protein / target
Claudin-18
Protein at a glance
Biological role
Structural molecule activity
Primary system
Musculoskeletal system
Strongest disease association
retinal disorder
Therapeutic maturity
Clinically validated target
Druggability
Antibody
Clinical development
1 approved
Derived from structured UniProt, Open Targets and literature data on this page.
Protein profile
Canonical identity and biological annotation from UniProt.
Function
Involved in alveolar fluid homeostasis via regulation of alveolar epithelial tight junction composition and therefore ion transport and solute permeability, potentially via downstream regulation of the actin cytoskeleton organization and beta-2-adrenergic signaling (By similarity). Required for lung alveolarization and maintenance of the paracellular alveolar epithelial barrier (By similarity). Acts to maintain epithelial progenitor cell proliferation and organ size, via regulation of YAP1 localization away from the nucleus and thereby restriction of YAP1 target gene transcription (By similarity). Acts as a negative regulator of RANKL-induced osteoclast differentiation, potentially via relocation of TJP2/ZO-2 away from the nucleus, subsequently involved in bone resorption in response to calcium deficiency (By similarity). Mediates the osteoprotective effects of estrogen, potentially via acting downstream of estrogen signaling independently of RANKL signaling pathways (By similarity)
Subcellular location
Domains and Gene Ontology detail (16)Hide
Gene Ontology
- Cbicellular tight junction
- Ccell-cell junction
- Clateral plasma membrane
- Cplasma membrane
- Fidentical protein binding
- Fstructural molecule activity
- Pcalcium-independent cell-cell adhesion
- Pcellular response to estrogen stimulus
- Pepithelial cell proliferation
- Pepithelial fluid transport
- Plung alveolus development
- Pnegative regulation of protein localization to nucleus
Biological roles
What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.
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Cell adhesion
- ·Involved in alveolar fluid homeostasis via regulation of alveolar epithelial tight junct…
- ·Cell junction, tight junction
- ·bicellular tight junction
- ·cell-cell junction
Immune signalling
- ·calcium-independent cell-cell adhesion
Transcriptional regulation
- ·Involved in alveolar fluid homeostasis via regulation of alveolar epithelial tight junct…
View underlying pathways (1)Hide underlying pathways
Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.
Interaction neighbourhood
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.
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
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.
Claudin-18 binding agent
Appears in clinical studies involving gastric cancer, neoplasm of esophagus, gastric neoplasm, neoplasm
ChEMBL mechanism, action type and target identity. Open Targets clinical status and indications.
Translational evidence
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.
Highest-confidence therapeutic associations
Diseases where a drug acting on this target has already reached clinical development.
Highest overall evidence
Remaining associations by Open Targets' aggregated evidence score.
Show all associationsHide all associations
Open Targets ranks 484 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 · 1 total
gastric cancer · neoplasm of esophagus · gastric neoplasm
Tractability
Clinical trials
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 (10)Hide
ClinicalTrials.gov via the drug-target graph.
Forefront confidence
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.
This ranking differs from Open Targets' own: re-weighting moves genetically-evidenced diseases above more heavily co-mentioned ones. 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
Recent activity around this target, drawn from one canonical event stream. Every item is reached through a drug that targets this protein, so each event is news about that drug rather than about the protein directly.
- Regulatory approval
Approval: Vyloy (EMA)
- New publicationILUSTRO: Phase II Multicohort Trial of Zolbetuximab in Patients with Advanced or Metastatic Claudin 18.2-Positive Gastric or Gastroesophageal Junction Adenocarcinoma.
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.