EGFR and neoplasm: Through a complex mechanism which involves a DNA damage signaling pathway, interferon γ (IFNγ) signaling, the cyclic GMP–AMP synthase–stimulator of interferon genes (cGas–STING) pathway, and the epidermal growth factor receptor (EGFR) pathway, the PD-L1 receptor of the tumor cells is upregulated [50].