METTL3 and lung adenocarcinoma: Moreover, METTL3 also upregulates the level of miR-1246 which reduces the expression of the tumor suppressor PEG3 to promote the development of lung adenocarcinoma (Huang et al., 2021b); In addition, METTL3 can also promote tumor proliferation, EMT, invasion, and migration by down-regulating miRNAs, such as: miR-1915-3p (Pan et al., 2021a).