Wu performed scRNA Seq (Chromium, 10X Genomics) on 26 primary tumors from three major clinical subtypes of breast cancer, including 11 ER+ BC, 5 HER2+ BC, and 10 triple-negative breast cancer; this allowed us the opportunity to investigate the involvement of EPGs in the microenvironment for subtypes of HER2+ BC [53]. The gene discussed is ERBB2; the disease is breast cancer.