EGFR and cancer: The inflammatory cytokine IFN-γ is the best-characterized stimulus for PD-L1 expression, but several studies suggest that cell-intrinsic oncogenic signaling can also promote PD-L1 expression in cancer cells through epidermal growth factor receptor (EGFR), the transcription factor MYC, and the kinase AKT (Akbay et al., 2013, Casey et al., 2016, Parsa et al., 2007).