ERBB2 and breast cancer: Initially, we accessed www.cbioportal.org and downloaded data pertaining to invasive breast carcinoma (TCGA, Nature 2012).(5,6) The collected data refer to the expression of messenger RNA (mRNA) for HPSE and HPSE2 in different subtypes of breast cancer, such as luminal A/B (n=321), triple-negative/basal (n=81), and HER2 (n=58) (Figure 1).