METTL3 and diffuse large B-cell lymphoma: The pathogenesis of diffuse large B-cell lymphoma (DLBCL), which is the most common subtype of lymphoma derived from B lymphocytes, has been illustrated to have a link with upregulated METTL3 and the m6A level of the mRNA of pigment epithelium-derived factor (Cheng et al., 2020), while PIWI-interacting RNAs have been identified to function in this process recently (Han et al., 2021).