ALYREF and breast cancer: ALYREF, also known as THOC4, is another specific m5C-binding protein that recognizes and binds to m5C regions in RNA through the lysine 171 residue, thereby regulating mRNA nuclear export.56 Wang et al. 57 demonstrated that ALYREF specifically binds to highly-methylated m5C sites within the mRNAs of RABL6 and TK1, promoting the splicing and stability of these transcripts, which are associated with the malignancy of BC.