NEDD8 and cancer: Numerous studies have proven that NEDD8 and NEDDylation enzymes (e.g., NAE, UBE2M, UBE2F, DCN1, and NEDD8 E3 ligases) are overexpressed in human cancers, including lung cancer [135], liver cancer [136], colorectal cancer [41], intrahepatic cholangiocarcinoma [137], nasopharyngeal carcinoma [138], esophageal squamous cell carcinoma [139], and glioblastoma [140].