The Potential Role of N6-Methyladenosine (m6A) Demethylase Fat Mass and Obesity-Associated Gene (FTO) in Human Cancers

N6-methyladenosine (m6A) demethylase fat mass and obesity-associated gene (FTO), previously recognized to be related with obesity and diabetes, was gradually discovered to be dysregulated in multiple cancers and plays an oncogenic or tumor-suppressive role. However, the specific expression and pro- or anti-cancer role of FTO in various cancers remained controversial. In this review, through summarizing the available literature, we found that FTO single nucleotide polymorphisms (SNPs) were closely related with cancer risk. Additionally, the dysregulation of FTO was implicated in multiple biological processes, such as cancer cell apoptosis, proliferation, migration, invasion, metastasis, cell-cycle, differentiation, stem cell self-renewal and so on. These modulations mostly relied on the communications between FTO and specific signaling pathways, including PI3K/AKT, MAPK and mTOR signaling pathways. Furthermore, FTO had great potential for clinical application by serving as a prognostic biomarker.