To determine the role and mechanism of METTL3 in reversing gefitinib resistance mediated by autophagy, we first analyzed the different protein expression of METTL3 in normal tissues and lung adenocarcinoma tissues by using TCGA database, and found that METTL3 was significantly higher expressed in lung adenocarcinoma patients (Fig. 5D). Here, METTL3 is linked to lung adenocarcinoma.