YTHDF2 and cancer: In mammals, YTH proteins are categorized as YTHDC1, YTHDC2, and YTHDF, with only one YTHDF subfamily homologous protein in most invertebrates and three YTHDF homologous proteins, YTHDF1, YTHDF2, and YTHDF3, in most vertebrates [33], which are strongly associated with cancers through their binding to the m6A site of RNA and affecting the RNA processing progress such as splicing, stability, or translation [34].