The human HER2 gene with the generic name ERBB2 (also known as NEU) encodes the HER2 protein or p185HER2. The HER2 protein is a membrane receptor tyrosine kinase with homology to the epidermal growth factor receptor (EGFR). The HER2 gene is a normal component present in two copies in all normal diploid cells.
In a fraction of patients (15-20%) with breast cancer, the HER2 gene is amplified as a part of the process of malignant transformation and tumor progression. HER2 gene amplification leads to overexpression of the HER2 protein on the surface of breast cancer cells.
HER2 gene amplification and receptor prevalence correlates with poor breast cancer prognosis, including relapse-free and overall survival.
HER2 IQFISH pharmDx is the latest Dako HER2 diagnostic kit indicated as an aid in the assessment of patients for whom Herceptin treatment is considered.