Circulating tumour cells (CTCs) as a novel analyte for monitoring HER2 status
Overcoming limitations of tissue-based tests
Testing of human epidermal growth factor receptor 2 (HER2) is recommended for all newly diagnosed breast cancer cases and at disease recurrence 1-3. Our new HER2 assay identifies and quantifies HER2 protein expression and gene amplification in CTCs from a single blood sample. This approach may overcome the challenge of local or distant recurrence where tissue biopsies may be out-of-date or not accessible in inoperable patients.
Association with poor prognosis
The presence of HER2-positive CTCs in patients with breast cancer, particularly those with initially HER2-negative primary tumours, has been associated with poor prognosis 4-6.
Critical role in disease progression
Studies have shown that patients with HER2-negative tumours, but HER2-positive CTCs, have shorter survival, suggesting that HER2 expression on CTCs plays a critical role in disease progression 4,7.
Predictive value for treatment response
Patients with HER2-negative primary tumours, but HER2-positive CTCs, who received lapatinib in the DETECT III trial, showed improved overall survival compared with those who did not receive the targeted therapy 6.
Our HER2 assay can help identify individuals with HER2-positive CTCs and prior HER2-negative primary tumours, and may assist in identifying those who could benefit from HER2-targeted treatments within a clinical trial.
Potential prognostic marker for longitudinal monitoring
HER2 status changes with breast cancer progression, with enrichment of HER2-low tumours in advanced stages 8. HER2-positive CTCs have been detected across early and metastatic stages of breast cancer 5, suggesting their potential as a prognostic marker throughout the disease course 9.
Our new HER2 assay has the potential to enable more accurate patient stratification for clinical trials and subsequent longitudinal monitoring.
Representative images of a single epithelial cancer cell (SKBR3) positive for HER2 by both IF and HER2 FISH (HER2/CEN17 ratio = >4)
A. 10x merge image after IF staining, showing epithelial markers in white (Cy5), mesenchymal markers in purple (Cy7), HER2 protein in orange (Cy3), DNA in blue (DAPI), blood lineage markers in green (FITC).
B. Left to right: 60x merge FISH staining of the same cell, HER2 foci in orange (Cy3), CEN17 foci in green (FITC).
Micron bar = 20 μm.
Why choose ANGLE's HER2 testing service?
Benefits for your clinical research:
The presence of HER2-positive CTCs in patients with initially HER2-negative primary tumours has significant potential implications.
- Association with poor prognosis.
- Potential prognostic marker for longitudinal monitoring.
- Optimised patient selection, through fast and accurate indicators of therapeutic performance.
- Early competitive advantage by understanding therapeutic response sooner.
- Reduced trial size, costs and time.
Expert service:
ANGLE’s extensive experience in CTC testing, combined with our global presence ensures:
- Highly accurate, repeatable, and precise HER2 CTC results.
- Exceptional data quality and timely reporting.
- Global clinical study support.
- Flexibility to accommodate your clinical study schedule.
Novel HER2 assay for CTCs
Our new assay identifies and quantifies HER2 in epithelial, mesenchymal and epithelial-to-mesenchymal (EMT) CTCs from a single blood sample. HER2 protein expression is identified via immunofluorescence (IF) staining, and HER2/neu gene amplification is quantified via fluorescence in situ hybridisation (FISH). Available through our GCLP-compliant laboratory, for research use only.
HER2 positivity rate for IF (protein expression) and FISH (gene amplification)*
Table 1. Key performance metrics using epithelial, HER2-positive SKBR3 cells, spiked and recovered from peripheral blood using the Parsortix® instrument.
IF
100%
HER2 positivity rate
FISH†
96%
HER2 positivity rate
Analytical sensitivity and specificity for epithelial, mesenchymal and blood lineage markers**
Table 2. Key performance metrics using epithelial, HER2- positive SKBR3 cells, and mesenchymal, HER2-low Hs 578T cells spiked and recovered from peripheral blood using the Parsortix instrument. Overall analytical sensitivity and specificity data generated from SKBR3 cells (epithelial sensitivity, mesenchymal and blood lineage specificity), Hs 578T cells (mesenchymal sensitivity, epithelial and blood lineage specificity) and white blood cells (blood lineage sensitivity).
Epithelial markers
>99%
Analytical Sensitivity
Epithelial markers
98%
Analytical Specificity
Mesenchymal Markers
97%
Analytical Sensitivity
Mesenchymal Markers
>99%
Analytical Specificity
Blood lineage Markers
>99%
Analytical Sensitivity
Blood lineage Markers
97%
Analytical Specificity
Other services to support your team
ANGLE’s Biopharma Laboratory Services offer a suite of complementary CTC enrichment and analysis solutions to enhance your cancer therapy clinical studies.
Our services include:
We can also develop bespoke molecular and imaging CTC assays, specific to your requirements.
For Research Use Only. Not For Use In Diagnostic Procedures.
Discover how HER2 testing service can transform your clinical trial
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*HER2 positivity rate (FISH) = Proportion of harvested SKBR3 cancer cells with a HER2/CEN17 foci ratio ≥2; HER2 positivity rate (IF) = Proportion of harvested SKBR3 cells which were positive for HER2 in the assay.
**Analytical sensitivity = Proportion of harvested cells known to express the marker(s) of interest which were marker positive in the assay. Analytical specificity = Proportion of harvested cells known to NOT express the marker(s) of interest which were marker negative in the assay.
References: 1. NCCN Guidelines version 4.2024. Breast Cancer. https://www.nccn.org/professionals/physician_gls/pdf/breast.pdf. 2. NICE. Early and locally advanced breast cancer: diagnosis and management. https://www.nice.org.uk/guidance/ng101. 3. NICE. Advanced breast cancer: diagnosis and management. https://www.nice.org.uk/guidance/cg81. 4. Müller V, Banys-Paluchowski M, Friedl TWP, et al. Prognostic relevance of the HER2 status of circulating tumor cells in metastatic breast cancer patients screened for participation in the DETECT study program. ESMO Open. 2021;6(6):100299. 5. Weirong C, Juncheng Z, Lijian H, et al. Detection of HER2-positive circulating tumor cells using the liquid biopsy system in breast cancer. Clinical Breast Cancer. 2019;19 (1):239-246. 6. Fehm T, Mueller V, Banys-Paluchowski M, et al. Efficacy of Lapatinib in patients with HER2-negative metastatic breast cancer and HER2-positive circulating tumor cells—The DETECT III clinical trial. Clin Chem. 2024;70(1):307-318. 7. Verschoor N, Bos MK, de Kruijff IE, et al. Trastuzumab and first-line taxane chemotherapy in metastatic breast cancer patients with a HER2-negative tumor and HER2-positive circulating tumor cells: a phase II trial. Breast Cancer Res Treat. 2024;205(1):87-95. 8. Bergeron A, Bertaut A, Beltjens F, et al. Anticipating changes in the HER2 status of breast tumours with disease progression—towards better treatment decisions in the new era of HER2-low breast cancers. Br J Cancer. 2023;129(1):122-134. 9. Munzone E, Botteri E, Sandri MT, Esposito A, Adamoli L, Zorzino L, Sciandivasci A, Cassatella MC, Rotmensz N, Aurilio G, Curigliano G, Goldhirsch A, Nolè F. Prognostic value of circulating tumor cells according to immunohistochemically defined molecular subtypes in advanced breast cancer. Clin Breast Cancer. 2012 Oct;12(5):340-6.