EGFR, HER2, HER3 and HER4: The ERBB Receptor Family
EGFR (ERBB1), HER2 (ERBB2), HER3 (ERBB3) and HER4 (ERBB4) are related receptor tyrosine kinases. Their activity is shaped by ligand binding, receptor pairing and cellular context, which is why a biomarker result in one family member does not automatically describe the others.
Quick Answer
EGFR (ERBB1), HER2 (ERBB2), HER3 (ERBB3) and HER4 (ERBB4) are related receptor tyrosine kinases. Their activity is shaped by ligand binding, receptor pairing and cellular context, which is why a biomarker result in one family member does not automatically describe the others.
A Family of Signalling Receptors
ERBB receptors span the cell membrane and relay extracellular signals into pathways including MAPK and PI3K–AKT. Ligand binding and dimer formation are important parts of normal regulation.
HER2 is notable for its preferred receptor-pairing role, while HER3 has an impaired kinase domain but can contribute through heterodimerisation. These functional differences make family-level shorthand incomplete.
From Biology to Biomarker
A sequence variant, amplification or expression result in one ERBB gene should retain its exact gene and test type. Receptor-family biology provides context, but does not substitute for validated disease-specific testing.
Downstream alterations such as KRAS or PIK3CA can also affect pathway behaviour. Molecular reports are most useful when read as a connected profile rather than a single isolated gene.
Key Takeaways
- ·EGFR, HER2, HER3 and HER4 are related but non-identical receptors.
- ·Receptor pairing helps explain their signalling behaviour.
- ·A result in one ERBB gene does not automatically apply to another.
Put these genes in pathway context
Frequently asked questions
What is the key idea in EGFR, HER2, HER3 and HER4: The ERBB Receptor Family?
EGFR (ERBB1), HER2 (ERBB2), HER3 (ERBB3) and HER4 (ERBB4) are related receptor tyrosine kinases. Their activity is shaped by ligand binding, receptor pairing and cellular context, which is why a biomarker result in one family member does not automatically describe the others.
What should be kept with the result or mechanism?
EGFR, HER2, HER3 and HER4 are related but non-identical receptors. Receptor pairing helps explain their signalling behaviour. A result in one ERBB gene does not automatically apply to another.
References
Continue Reading
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How Trastuzumab Works: Targeting the HER2 Receptor
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Move from this explanation into a gene profile, a pathway map, or the next evidence update.
EGFR has 1000+ trials currently recruiting on ClinicalTrials.gov. The GeneAnalyses digest summarises the new and changed ones each day.