FIGURE 1.

The immune characteristics of tumors with EGFR mutation. EGFR‐mutant tumors have low infiltration of CD8⁺ T cells and high expression of Treg and CD73. Treg cells can secrete IL‐10, IL‐35, and TGF‐β to reduce anti‐tumor immune responses mediated by NK cells and CD8⁺ T cells. DCs can secrete IDO, which promotes the conversion of CD3⁺CD4⁺ CD25‐T cells to Tregs. CD73 promotes ATP decomposition into ADO. A2A is an ADO receptor that is widely expressed in lung cancer. The CD73‐ADO axis promotes the efficacy of Tregs and MDSCs. ADO combined with A2AR also inhibits T cell signal transduction, thus impairing anti‐tumor immunity. Moreover, EGFR‐mutant tumors secrete exosomes containing EGFR mutations to promote distant metastasis. Abbreviations: EGFR, epidermal growth factor receptor; PD‐L1, programmed death‐ligand 1; ADO, adenosine; PD‐1, programmed cell death protein 1; DC, dendritic cell; IDO, indoleamine 2, 3‐ dioxygenase; Treg, regulatory T cell; NK, natural killer; A2AR, adenosine A2A receptor; MDSC, myeloid‐derived suppressor cell