The activation of PI3K/AKT signaling pathway in cancers promotes PD-L1 expression (Atefi et al. 2014; Lastwika et al. 2016), and HER2 overexpression activates PI3K/AKT signaling pathway (Vernieri et al. 2020; Li et al. 2011b). The gene discussed is ERBB2; the disease is cancer.