CLOCK and cancer: In the liver of Clock Δ19 mutant mice, a total of 61 and 57 miRNAs were differentially expressed at zeitgeber time (ZT) 2 and 14, respectively, which were mainly involved in “pathways in cancer,” “PI3K-Akt signaling pathway,” and “MAPK signaling pathway.” Among these miRNAs, miR-340-3p (targeting Clock, Per1, and Cry2), miR-669d (targeting Per2), miR-374 (targeting Per3), and miR-338-5p (targeting Nr1d1) directly targeted core circadian genes [83].