Epitranscriptic regulation of by -methyladenosine drives tumor progression.

Overexpression of Ras, in addition to the oncogenic mutations, occurs in various human cancers. However, the mechanisms for epitranscriptic regulation of in tumorigenesis remain unclear. Here, we report that the widespread -methyladenosine (mA) modification of , but not and , is higher in cancer tissues compared with the adjacent tissues, which results in the increased expression of H-Ras protein, thus promoting cancer cell proliferation and metastasis. Mechanistically, three mA modification sites of 3' UTR, which is regulated by FTO and bound by YTHDF1, but not YTHDF2 nor YTHDF3, promote its protein expression by the enhanced translational elongation. In addition, targeting mA modification decreases cancer proliferation and metastasis. Clinically, up-regulated H-Ras expression correlates with down-regulated FTO and up-regulated YTHDF1 expression in various cancers. Collectively, our study reveals a linking between specific mA modification sites of and tumor progression, which provides a new strategy to target oncogenic Ras signaling.