MTOR and neoplasm: Similarly, hsa_circ0001666 [129], circRNA membrane bound O-acyltransferase domain containing 2 (circMBOAT2) [130], and circRNA nuclear factor of activated T cells 3 (circNFATC3) [131] could also act as ceRNAs to regulate tumor progression via the AKT-mTOR axis (Figure 3).