Remarkably, although EGFR activation was shown to increase PD-L1 expression through multiple signal pathways, a controversial correlation between EGFR activation mutations and PD-L1 expression was observed in NSCLC patients (256, 288–290), which may be attributed to the complicated regulation of PD-L1 expression (inducible and constitutive) in vivo. The gene discussed is CD274; the disease is non-small cell lung carcinoma.