Interaction between N6-methyladenosine (m6A) modification and noncoding RNAs in cancer.

As a critical internal RNA modification in higher eukaryotes, N6-methyladenosine (m6A) has become the hotspot of epigenetics research in recent years. Extensive studies on messenger RNAs have revealed that m6A affects RNA fate and cell functions in various bioprocesses, such as RNA splicing, export, translation, and stability, some of which seem to be directly or indirectly regulated by noncoding RNAs. Intriguingly, abundant noncoding RNAs such as microRNAs, long noncoding RNAs, circular RNAs, small nuclear RNAs, and ribosomal RNAs are also highly modified with m6A and require m6A modification for their biogenesis and functions. Here, we discuss the interaction between m6A modification and noncoding RNAs by focusing on the functional relevance of m6A in cancer progression, metastasis, drug resistance, and immune response. Furthermore, the investigation of m6A regulatory proteins and its inhibitors provides new opportunities for early diagnosis and effective treatment of cancer, especially in combination with immunotherapy.