# EPHB3

Source: https://onco.cc/targets/ephb3/  
OnCo record `ephb3` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

EPHB3 (Ephrin type-B receptor 3) is a protein kinase, an enzyme that switches other proteins on by adding phosphate groups. The public catalogues list it as a drug target, and an approved or late-stage drug is recorded against it. Tied to Thyroid cancer and Neuroendocrine tumours.

## Summary

Receptor tyrosine kinase which binds promiscuously transmembrane ephrin-B family ligands residing on adjacent cells, leading to contact-dependent bidirectional signalling into neighboring cells. The signalling pathway downstream of the receptor is referred to as forward signalling while the signalling pathway downstream of the ephrin ligand is referred to as reverse signalling. Generally has an overlapping and redundant function with EPHB2.

Open Targets scores its association with cancer at 0.60 (direct and indirect evidence; datatypes literature 0.90, genetic association 0.05, clinical 0.93).

## Fields

- Kind: Target
- Last checked: 2026-09-23
- Also known as: EPH receptor B3; Ephrin type-B receptor 3; Hek2; Tyro6; ETK2
- Tags: cancer-genes-wave
- Symbol: EPHB3
- Class: kinase
- Biology: Receptor tyrosine kinase which binds promiscuously transmembrane ephrin-B family ligands residing on adjacent cells, leading to contact-dependent bidirectional signalling into neighboring cells. The signalling pathway downstream of the receptor is referred to as forward signalling while the signalling pathway downstream of the ephrin ligand is referred to as reverse signalling. Generally has an overlapping and redundant function with EPHB2. Like EPHB2, functions in axon guidance during development regulating for instance the neurons forming the corpus callosum and the anterior commissure, 2 major interhemispheric connections between the temporal lobes of the cerebral cortex. In addition to its role in axon guidance also plays an important redundant role with other ephrin-B receptors in development and maturation of dendritic spines and the formation of excitatory synapses. Controls other aspects of development through regulation of cell migration and positioning. Location: Cell membrane; Cell projection, dendrite (UniProt). Locus 3q27.1 (HGNC).
- Where found: Thyroid cancer: Open Targets association 0.56 with thyroid cancer (MONDO_0002108); Neuroendocrine tumours: Open Targets association 0.54 with neuroendocrine neoplasm (MONDO_0019496)

## Notes

- Written by scripts/fetch-cancer-genes.ts from CIViC, Open Targets, IntOGen, HGNC and UniProt; the function text is UniProt's, condensed and in UK spelling. Roles: Open Targets known-drug datatype score 0.93. Evidence tier "approved-drug" is the strongest of those signals.
- Prevalence not recorded: none of the sources gives a positivity rate.

## Sources

- HGNC HGNC:3394: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:3394
- UniProt P54753: https://www.uniprot.org/uniprotkb/P54753/entry
- NCBI Gene 2049: https://www.ncbi.nlm.nih.gov/gene/2049
- Ensembl ENSG00000182580: https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000182580

## Connected records

- collections: [Open Targets Platform](https://onco.cc/collections/open-targets/)
- cancers: [Neuroendocrine tumours](https://onco.cc/cancers/neuroendocrine/), [Thyroid cancer](https://onco.cc/cancers/thyroid/)

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JSON: https://onco.cc/api/v1/entities/ephb3.json