Additionally, we determined the effect of USP15 in different subtypes of BC, including TNBC cells (HCC1937), HER2+/ERα- BC cells (SK-BR3), HER2+/ERα+ BC lines with tamoxifen resistance (BT474) and HER2+/ERα+ BC cells (MDA-MB361). The gene discussed is ERBB2; the disease is breast cancer.