USP21 and central nervous system cancer: These miR-637-targeted genes include HMGA1 [42], CDK6 [50], and WNT7A [10] in glioma, HEMGN in PTC [12], APLN in GC [15], USP21 in HCC [51], LY6E [36] and CTSB [24] in CHOL, NUPR1 in OSCC [25] and MM [33], HDAC4 in SaOS [32], ABL1 in CML [34], KLK4 in OC [28], PLXNB2 in OC [27], AKT1 in TNBC [37], PTC [13], and HCC [18, 20], AKT3 in TNBC [37], and RING1 in CCa [30].