> Back to BioSpot site

Method of HER2 gene copy number quantifi cation in samples with indeterminate ISH

Current oncology is focused towards the search and use of predictive biomarkers that could determine suitable patients for targeted therapy. One of the well-known predictive biomarker is HER2 gene, localized on 17q, which is amplifi ed in 15-20% breast cancer patients. HER2 amplifi cation is poor prognostic factor but predictor of good response to anti-HER2 therapy (trastuzumab, pertuzumab and lapatinib) which signifi cantly increase survival rates in both palliative and adjuvant settings. Anti-HER2 agents are approved for treatment of HER2- positive breast cancer patients usually determined by immunohistochemistry and in situ hybridization (ISH). The proper determination of HER2 status is therefore fundamentally important.

The HER2 DNA quantifi cation kit was developed as a complementary test method for the quantifi cation of HER2 gene in breast cancer patient samples which cannot be reliably evaluated by SH. The kit works on the basis of the three duplex quantitative real-time polymerase chain reactions (qPCR) and is applicable for DNA from formalin-fi xed, paraffi n-embedded (FFPE) tissue samples. The HER2 gene copy number status is compared with three reference genes – GCS1 (chromosome 2), DCK (chromosome 4) and EPN2 (chromosome 17). The kit reliably detects HER2 gene amplifi cation in samples containing at least 5% of strongly positive cells (approximately 20 HER2 gene copies per cell). High sensitivity and specifi city levels were validated using 223 breast cancer patient samples.

Presented product is able to determine HER2 gene status in breast cancer FFPE samples with indeterminate ISH result. This kit allows quick and reliable identifi cation of patients who could benefi t from targeted anti-HER2 therapy and is useful in clinical practice as an alternative DNA-based method when ISH fail.


Koudelakova V, Berkovcova J, Trojanec R, Vrbkova J, Radova L, Ehrmann J, Kolar Z, Melichar B, Hajduch M. Evaluation of HER2 gene status in breast cancer samples with indeterminate fl uorescence in situ hybridization by quantitative real-time PCR method. J Mol Diagn, 2015 May 5, doi: 10.1016/j.jmoldx.2015.03.007

Patent protection: PUV 2015-30957 (CZ) fi led 2015-04-13

Palacky University Olomouc – Institute of Molecular and Translational Medicine (IMTM), Faculty of Medicine and Dentistry