Neddylation is a PTM comparable with ubiquitination that conjugates a ubiquitin-like protein called neuronal-precursor-cell-expressed developmentally downregulated protein 8 (NEDD8) to a lysine residue in the target protein, modulating tumorigenesis by acting on tumor cells as well as tumor microenvironment (TME) components, such as immune cells, cancer-associated fibroblasts, and cancer-associated endothelial cells [130,131]. The gene discussed is NEDD8; the disease is neoplasm.