Advances of N6-methyladenosine modification on circular RNA in hepatocellular carcinoma
N6-methyladenosine(m6A)is a reversible epigenetic modification,which is one of the most abundant modifi-ers in eukaryotic cells,and has been commonly reported in messenger RNAs and non-coding RNAs.The processing modification of m6A regulates RNA transcription,processing,splicing,degradation,and translation,and plays an important role in the biologi-cal process of tumors.Circular RNA,which lacks the 5'cap structure,has been mistakenly regarded as a"junk sequence"generat-ed by accidental shearing during the transcription process.However,it has been found that circRNAs can be involved in tumor in-vasion and metastasis through microRNAs,binding proteins,translated peptides,and m6A modifications.In this paper,we re-viewed the role of m6A modifications in circRNA regulation and their functions in hepatocellular carcinoma,and discussed their po-tential clinical applications and future development in this field.