GO:0038128 ERBB2 signaling pathway: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0038128 (ERBB2 signaling pathway) describes signaling initiated by ligand binding to the ERBB2 (HER2/NEU) receptor at the cell surface, ending in regulation of downstream cellular processes such as transcription.
• ERBB2 cannot bind ligands on its own; it functions as a signal-amplifying tyrosine kinase within heterodimeric receptor pairs, most classically with EGFR/ERBB3.
• The pathway is a major oncogenic driver in breast, gastric, ovarian and other cancers, making ERBB2 one of the most therapeutically targeted receptors [1,2].
• Downstream effectors include PI3K/AKT, MAPK/ERK, SRC and Rac-Pak modules that control proliferation, survival, migration and transformation [2,4,6,8].
• ERBB2 signaling is also physiologically essential in the heart, where Neuregulin1-ErbB2 signaling provides cardioprotection.
• CRISPR knockout, point-mutation, knock-in and overexpression models are central tools for dissecting ERBB2 pathway causality and drug response [1,5].
Description
GO:0038128, the ERBB2 signaling pathway, is a biological process in which molecular signals are initiated by ligand binding to the tyrosine kinase receptor ERBB2 on the cell surface and terminate with regulation of a downstream cellular process such as transcription. ERBB2 (also known as HER2 or NEU) is a member of the EGFR/ERBB family of receptor tyrosine kinases and is unusual because it is itself unable to bind ligands, instead acting as a signal-amplifying tyrosine kinase within a heterodimeric receptor pair. This amplification role places ERBB2 at the center of growth factor signaling in normal development and in multiple human malignancies [1,2]. Because ERBB2 signaling integrates inputs from ligands such as Neuregulin1 and drives canonical cascades including PI3K/AKT and MAPK/ERK, it is one of the most intensively studied pathways in cancer biology and cardiology [2,3]. Its clinical importance is underscored by the success of ERBB2-directed therapies in breast and gastric cancer, and by the need to understand resistance mechanisms that emerge during treatment [1,2]. For researchers, GO:0038128 provides a structured framework for interrogating how receptor heterodimerization, phosphorylation and downstream effector recruitment control cell fate [1,5]. This article summarizes the definition, mechanism, key genes, disease links, experimental models and CRISPR-based research strategies relevant to the ERBB2 signaling pathway.
ERBB2 signaling pathway At A Glance
| GO ID | GO:0038128 |
|---|---|
| GO term | ERBB2 signaling pathway |
| Ontology | biological_process |
| Synonym | ERBB2 signalling pathway; HER2 signaling pathway; NEU signaling; receptor tyrosine-protein kinase erbB-2 signaling pathway |
| Major function | Ligand-initiated signal amplification through ERBB2-containing heterodimers, leading to regulation of downstream cellular processes such as transcription |
| Receptor class | Receptor tyrosine kinase (EGFR/ERBB family) |
| Ligand binding | ERBB2 itself does not bind ligands; it partners with ligand-bound ERBB family members |
| Key downstream cascades | PI3K/AKT and MAPK/ERK signaling [2,4,8] |
| Disease relevance | Breast cancer, gastric cancer, ovarian cancer and other malignancies [1,2,8] |
What Is GO:0038128?
The ERBB2 signaling pathway (GO:0038128) is the series of molecular signals initiated by binding of a ligand to the tyrosine kinase receptor ERBB2 on the surface of a cell, ending with regulation of a downstream cellular process such as transcription. ERBB2 receptors are themselves unable to bind ligands, but act as a signal-amplifying tyrosine kinase within a heterodimeric pair.
Why Is ERBB2 signaling pathway Important in Cell Biology?
ERBB2 signaling is important because it converts extracellular growth factor cues into potent intracellular proliferation and survival signals, and its dysregulation is a hallmark of several aggressive cancers [1,2]. At the same time, Neuregulin1-ErbB2 signaling is physiologically essential in the heart, so understanding this pathway is critical for both oncology and cardio-oncology. The pathway also serves as a paradigm for receptor tyrosine kinase biology, including heterodimerization, phosphorylation-dependent regulation and therapeutic resistance [1,5].
• Drives proliferation and survival in ERBB2-positive breast cancer and other tumors [1,2].
• Central to PI3K/AKT and MAPK/ERK oncogenic signaling [2,4,8].
• Mediates transformation of human breast epithelial cancer cells via Rac-Pak signaling.
• Regulates migration and invasion in ovarian cancer cells through MAPK1/MAPK3 signaling.
• Provides cardioprotective Neuregulin1-ErbB2 signaling in the heart.
• Is a validated therapeutic target for monoclonal antibodies and tyrosine kinase inhibitors.
• Underlies resistance mechanisms that limit current anti-HER2 therapies [1,2].
• Serves as a model for studying receptor heterodimerization and signal amplification [1,5].
• Can be modulated by direct receptor stimulation, revealing cytostatic signaling via Thr701 phosphorylation.
• Interacts with NOTCH3 signaling in ErbB2-negative breast cancer contexts.
What Happens During ERBB2 signaling pathway?
Ligand binding and heterodimerization
In simple terms: A growth factor ligand binds a partner receptor, and ERBB2 joins in to form a powerful signaling pair.
ERBB2 cannot bind ligands directly; instead, ligand binding occurs on a partner ERBB family receptor, after which ERBB2 is recruited into a heterodimeric pair that acts as a signal-amplifying tyrosine kinase. This heterodimerization is the initiating event of GO:0038128 and determines the strength and duration of downstream signaling.
Receptor phosphorylation and kinase activation
In simple terms: The receptor pair switches on by adding phosphate tags to itself.
Once heterodimerized, the ERBB2-containing receptor complex undergoes autophosphorylation on tyrosine residues, creating docking sites for downstream effector proteins. Phosphorylation at specific residues, such as Thr701, has been linked to a distinct cytostatic signaling output, highlighting that ERBB2 phosphorylation is not monolithic but can encode different biological outcomes.
Recruitment of PI3K/AKT and MAPK/ERK cascades
In simple terms: The activated receptor recruits relay proteins that tell the cell to grow and survive.
Phosphorylated ERBB2 heterodimers recruit adaptor proteins that activate the PI3K/AKT pathway, a major driver of survival and growth in HER2-positive breast cancer. In parallel, ERBB2 signaling engages the MAPK/ERK cascade, which transmits proliferative signals to the nucleus and regulates transcription [4,8]. In ovarian cancer cells, ERBB2 silencing reduces migration and invasion through modulation of MAPK1/MAPK3 signaling.
Cytoskeletal and transformation signaling via Rac-Pak
In simple terms: The pathway also reshapes the cell skeleton to promote transformation.
A Rac-Pak signaling pathway is essential for ErbB2-mediated transformation of human breast epithelial cancer cells, linking ERBB2 to cytoskeletal reorganization and malignant transformation. This illustrates that GO:0038128 extends beyond canonical kinase cascades to include Rho-family GTPase signaling.
Crosstalk with SRC and NOTCH3 signaling
In simple terms: ERBB2 signaling talks to other pathways to fine-tune cell behavior.
In nasopharyngeal carcinoma cells, inhibition of proliferation and induction of apoptosis by evodiamine involves the SRC/ERBB2-mediated MAPK/ERK signaling pathway, demonstrating crosstalk between SRC and ERBB2. Separately, NOTCH3 signaling plays crucial roles in the proliferation of ErbB2-negative human breast cancer cells, indicating context-dependent interplay between ERBB2 and NOTCH pathways.
Transcriptional output and cellular response
In simple terms: The signal reaches the nucleus and changes which genes are switched on.
The pathway ends with regulation of downstream cellular processes, including transcription, which ultimately controls proliferation, survival, migration and differentiation. This transcriptional output is the functional readout of GO:0038128 and the basis for its role in cancer and cardiac biology [1,3].
Key Genes Involved in GO:0038128 ERBB2 signaling pathway
The following genes and proteins are core components or well-documented modulators of the ERBB2 signaling pathway (GO:0038128).
| Gene | Major Role | Research Relevance |
|---|---|---|
| ERBB2 (HER2/NEU) | Signal-amplifying tyrosine kinase in heterodimeric receptor pairs | Primary receptor of GO:0038128; major oncogene and therapeutic target |
| EGFR (ERBB1) | Ligand-binding partner forming heterodimers with ERBB2 | Heterodimerization partner that initiates ERBB2 signaling |
| ERBB3 | Ligand-binding partner and potent PI3K activator in heterodimers | Key heterodimer partner in HER2-driven cancers |
| ERBB4 | ERBB family receptor that can heterodimerize with ERBB2 | Contributes to context-dependent ERBB2 signaling |
| NRG1 (Neuregulin1) | Ligand that activates ERBB2-containing heterodimers | Cardioprotective Neuregulin1-ErbB2 signaling in the heart |
| PIK3CA | Catalytic subunit of PI3K downstream of ERBB2 | Mediates PI3K/AKT survival signaling in HER2-positive breast cancer |
| AKT1 | Serine/threonine kinase downstream of PI3K | Effector of ERBB2-driven survival signaling |
| MAPK1 (ERK2) | Kinase in the MAPK/ERK cascade | Mediates ERBB2-dependent migration and invasion in ovarian cancer |
| MAPK3 (ERK1) | Kinase in the MAPK/ERK cascade | Transmits ERBB2 proliferative signals to the nucleus |
| SRC | Non-receptor tyrosine kinase crosstalking with ERBB2 | Modulates ERBB2-mediated MAPK/ERK signaling in nasopharyngeal carcinoma |
| RAC1 | Rho-family GTPase | Essential for ErbB2-mediated transformation via Rac-Pak signaling |
| PAK1 | Serine/threonine kinase downstream of Rac | Mediates cytoskeletal signaling in ErbB2 transformation |
| NOTCH3 | Transmembrane receptor in NOTCH signaling | Plays crucial roles in ErbB2-negative breast cancer proliferation |
| MAPK1/MAPK3 axis | Core MAPK cascade components | Mediates ERBB2 silencing effects on ovarian cancer migration |
| ERBB2 Thr701 | Phosphorylation site on ERBB2 | Linked to a novel cytostatic signaling pathway upon direct stimulation |
| HER2 extracellular domain | Ligand-independent receptor region | Target of therapeutic antibodies in HER2-positive cancers |
| HER2 intracellular kinase domain | Catalytic domain of ERBB2 | Target of tyrosine kinase inhibitors and resistance studies |
How Is ERBB2 signaling pathway Regulated?
ERBB2 signaling is regulated at multiple levels. Receptor heterodimerization with ligand-bound ERBB family members is required for activation because ERBB2 cannot bind ligands itself. Phosphorylation of specific residues, such as Thr701, can switch signaling toward cytostatic rather than proliferative outputs. Downstream, the PI3K/AKT and MAPK/ERK cascades are subject to feedback and crosstalk regulation, including input from SRC and NOTCH3 pathways [2,4,7]. In the heart, Neuregulin1-ErbB2 signaling is physiologically regulated to provide cardioprotection, illustrating tissue-specific control.
ERBB2 signaling pathway and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| ERBB2 | HER2-positive breast cancer [1,2] | ERBB2 knockout or overexpression in breast cancer cell lines |
| ERBB2 | Ovarian cancer migration and invasion | ERBB2 silencing in ovarian cancer cells with MAPK1/MAPK3 readout |
| SRC/ERBB2 | Nasopharyngeal carcinoma proliferation and apoptosis | SRC/ERBB2 pathway inhibition in nasopharyngeal carcinoma cells |
| NRG1/ERBB2 | Cardioprotection and cardio-oncology | Neuregulin1-ErbB2 signaling models in cardiac cells |
| NOTCH3 | ErbB2-negative breast cancer proliferation | NOTCH3 pathway perturbation in ErbB2-negative breast cancer cells |
ERBB2 signaling in breast cancer
ERBB2 (HER2) is a major oncogene in breast cancer, where amplification or overexpression drives PI3K/AKT and MAPK/ERK signaling to promote proliferation and survival [1,2]. HER2-positive breast cancer is treated with ERBB2-directed therapies, but resistance remains a clinical challenge, motivating continued research into pathway mechanisms [1,2]. A Rac-Pak signaling pathway is essential for ErbB2-mediated transformation of human breast epithelial cancer cells, linking the pathway to malignant transformation. In ErbB2-negative breast cancer cells, NOTCH3 signaling plays crucial roles in proliferation, highlighting context-dependent pathway interactions.
ERBB2 signaling in ovarian cancer
ERBB2 gene expression silencing is involved in ovarian cancer cell migration and invasion through mediation of MAPK1/MAPK3 signaling, indicating that ERBB2 signaling contributes to ovarian cancer cell behavior. This positions ERBB2 and its downstream MAPK effectors as potential targets for experimental and therapeutic investigation in ovarian cancer.
ERBB2 signaling in nasopharyngeal carcinoma
In nasopharyngeal carcinoma cells, evodiamine inhibits proliferation and induces apoptosis via the SRC/ERBB2-mediated MAPK/ERK signaling pathway, demonstrating that ERBB2 signaling can be pharmacologically modulated in this cancer type. This highlights SRC-ERBB2 crosstalk as a research focus in nasopharyngeal carcinoma.
ERBB2 signaling in cardiac biology and cardio-oncology
Neuregulin1-ErbB2 signaling plays a cardioprotective role in the heart, with important physiological and onco-cardiological implications. Because ERBB2-targeted cancer therapies can affect cardiac function, understanding this pathway is essential for balancing oncologic efficacy and cardiovascular safety.
From ERBB2 signaling pathway-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Is ERBB2 required for proliferation in a given cancer cell line? | CRISPR knockout of ERBB2 |
| Does a specific ERBB2 phosphorylation site control cytostatic signaling? | Point mutation at ERBB2 Thr701 |
| Can a tagged ERBB2 allele be used to track receptor complexes? | Knock-in of an epitope-tagged ERBB2 |
| Does ERBB2 overexpression drive transformation? | ERBB2 overexpression in breast epithelial cells |
| Does ERBB2 silencing affect migration and invasion? | ERBB2 knockdown or knockout with MAPK1/MAPK3 readout |
| Does SRC-ERBB2 crosstalk modulate MAPK/ERK signaling? | SRC/ERBB2 perturbation in nasopharyngeal carcinoma cells |
How to Study the ERBB2 signaling pathway Process
| Method | What It Measures | Typical Application |
|---|---|---|
| RNA sequencing | Transcriptional changes downstream of ERBB2 signaling | Profiling PI3K/AKT and MAPK/ERK target genes |
| Phosphoproteomics | Receptor and downstream phosphorylation events | Mapping ERBB2 Thr701 and other phosphosites |
| Kinase activity assay | Tyrosine kinase activity of ERBB2 heterodimers | Evaluating receptor activation states |
| Proliferation assay | Cell growth in response to ERBB2 signaling | Testing pathway inhibitors or genetic perturbations |
| Apoptosis assay | Cell death induction upon pathway modulation | Evaluating therapeutic responses in cancer cells |
| Migration/invasion assay | Metastatic potential linked to ERBB2 signaling | Studying ovarian cancer cell behavior |
| Co-immunoprecipitation | Protein-protein interactions in ERBB2 complexes | Detecting heterodimerization partners |
| Immunofluorescence imaging | Subcellular localization of ERBB2 and effectors | Visualizing receptor trafficking and complexes |
Transcriptomic and pathway profiling
RNA sequencing and pathway-focused expression profiling can measure transcriptional outputs downstream of ERBB2 signaling, including PI3K/AKT and MAPK/ERK target genes [2,8]. Such approaches help define the functional consequences of ERBB2 pathway activation or inhibition in cancer models.
Phosphoproteomics and kinase assays
Phosphoproteomic and kinase activity assays can quantify ERBB2 autophosphorylation and downstream phosphorylation events, including site-specific phosphorylation such as Thr701. These methods are essential for dissecting how distinct phosphorylation states encode different signaling outcomes.
Functional proliferation, apoptosis and migration assays
Proliferation, apoptosis and migration assays are used to link ERBB2 signaling to cellular phenotypes, as shown in nasopharyngeal carcinoma and ovarian cancer studies [4,8]. These readouts are standard for evaluating pathway perturbation by genetic or pharmacological means [4,8].
Imaging and protein interaction studies
Imaging and protein interaction approaches can visualize ERBB2 heterodimerization, localization and complex formation at the cell surface. Such studies complement biochemical assays to build a mechanistic picture of GO:0038128.
How CRISPR Can Be Used to Study GO:0038128 ERBB2 signaling pathway
Knockout
CRISPR knockout of ERBB2 or its downstream effectors can establish causal requirements for the ERBB2 signaling pathway in proliferation, survival and migration [1,8]. For example, ERBB2 silencing reduces ovarian cancer cell migration and invasion through MAPK1/MAPK3 signaling, a phenotype that can be recapitulated with CRISPR knockout.
Point Mutation
Point mutations at specific ERBB2 phosphorylation sites, such as Thr701, allow researchers to dissect how individual phospho-events shape signaling output. Such models are valuable for separating cytostatic from proliferative arms of GO:0038128.
Knock-in
Knock-in of tagged or reporter ERBB2 alleles enables tracking of receptor expression, localization and complex formation in live cells. This approach supports mechanistic studies of heterodimerization and signal amplification.
Overexpression
CRISPR-based overexpression or activation of ERBB2 can model oncogenic transformation, as seen in ErbB2-mediated transformation of human breast epithelial cancer cells. Overexpression models are also useful for testing therapeutic resistance mechanisms.
How EDITGENE Supports ERBB2 signaling pathway Research
Researchers studying ERBB2 signaling pathway-related genes often need to determine whether a candidate gene is causally involved in pathway output, and CRISPR-based models provide a precise way to test such hypotheses [1,5].
Contact EDITGENE today to design your custom CRISPR model for ERBB2 signaling pathway research.
Frequently Asked Questions About ERBB2 signaling pathway
What is the ERBB2 signaling pathway (GO:0038128)?
It is the series of molecular signals initiated by ligand binding to the ERBB2 tyrosine kinase receptor at the cell surface, ending with regulation of a downstream cellular process such as transcription; ERBB2 itself does not bind ligands but amplifies signals within heterodimeric pairs.
What genes are involved in ERBB2 signaling pathway?
Core genes include ERBB2 (HER2/NEU), EGFR, ERBB3, ERBB4, NRG1, PIK3CA, AKT1, MAPK1, MAPK3, SRC, RAC1, PAK1 and NOTCH3 [1,2,3,4,6,7,8].
Why is ERBB2 signaling important in cancer?
ERBB2 signaling drives proliferation and survival through PI3K/AKT and MAPK/ERK cascades and is a major oncogenic driver in breast, ovarian and other cancers [1,2,8].
Does ERBB2 bind ligands directly?
No, ERBB2 receptors are unable to bind ligands themselves; they act as signal-amplifying tyrosine kinases within heterodimeric pairs.
What is the role of Neuregulin1-ErbB2 signaling in the heart?
Neuregulin1-ErbB2 signaling plays a cardioprotective role in the heart, with important physiological and onco-cardiological implications.
How is ERBB2 signaling studied experimentally?
Common approaches include RNA sequencing, phosphoproteomics, kinase assays, proliferation and apoptosis assays, migration assays, co-immunoprecipitation and imaging [1,2,4,5,8].
What CRISPR models are used for ERBB2 pathway research?
Knockout, point mutation, knock-in and overexpression models are used to test causal roles of ERBB2 and its effectors [1,5,6,8].
What downstream pathways does ERBB2 activate?
ERBB2 activates PI3K/AKT and MAPK/ERK signaling, and can crosstalk with SRC and Rac-Pak pathways [2,4,6,8].
Is ERBB2 signaling involved in ovarian cancer?
Yes, ERBB2 gene expression silencing affects ovarian cancer cell migration and invasion through MAPK1/MAPK3 signaling.
What is the relationship between ERBB2 and NOTCH3 signaling?
NOTCH3 signaling plays crucial roles in the proliferation of ErbB2-negative human breast cancer cells, indicating context-dependent interplay.
Conclusion
GO:0038128, the ERBB2 signaling pathway, is a central biological process that converts ligand-initiated cues into potent proliferative, survival and migratory signals through ERBB2-containing heterodimers. Its roles in breast, ovarian and nasopharyngeal cancers, as well as in cardiac protection, make it a high-priority research and therapeutic target [1,2,3,4,8]. CRISPR-based knockout, point-mutation, knock-in and overexpression models, combined with transcriptomic, phosphoproteomic and functional assays, provide powerful tools for dissecting this pathway [1,5,6,8]. Continued investigation of ERBB2 signaling mechanisms and crosstalk will inform new strategies to overcome resistance and improve patient outcomes [1,2].
References
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- 2. Pan L et al.. 2024. HER2/PI3K/AKT pathway in HER2-positive breast cancer: A review.. Medicine (Baltimore) 103(24):e38508 PMID: 38875362
- 3. Mikami Y et al.. 2026. Cardioprotective Role of Neuregulin1-ErbB2 Signaling Pathway: Its Physiological and Onco-Cardiological Roles in the Heart.. Biol Pharm Bull 49(1):24-29 PMID: 41485987
- 4. Liu J et al.. 2024. Evodiamine inhibits proliferation and induces apoptosis of nasopharyngeal carcinoma cells via the SRC/ERBB2-mediated MAPK/ERK signaling pathway.. J Transl Med 22(1):859 PMID: 39334374
- 5. Gaviraghi M et al.. 2020. Direct stimulation of ERBB2 highlights a novel cytostatic signaling pathway driven by the receptor Thr(701) phosphorylation.. Sci Rep 10(1):16906 PMID: 33037285
- 6. Arias-Romero LE et al.. 2010. A Rac-Pak signaling pathway is essential for ErbB2-mediated transformation of human breast epithelial cancer cells.. Oncogene 29(43):5839-49 PMID: 20711231
- 7. Yamaguchi N et al.. 2008. NOTCH3 signaling pathway plays crucial roles in the proliferation of ErbB2-negative human breast cancer cells.. Cancer Res 68(6):1881-8 PMID: 18339869
- 8. Yu TT et al.. 2020. ERBB2 gene expression silencing involved in ovarian cancer cell migration and invasion through mediating MAPK1/MAPK3 signaling pathway.. Eur Rev Med Pharmacol Sci 24(10):5267-5280 PMID: 32495860
