{"type":"root","children":[{"type":"paragraph","children":[{"type":"text","value":"MDM2 (Mouse Double Minute 2 homolog) is an E3 ubiquitin ligase that binds to the trans-activation domain (TAD) of tumor suppressor p53. This leads to the degradation of p53 and the downregulation of p53 target genes involved in cell cycle arrest, apoptosis, DNA repair, and senescence. MDM2 prevents p53 activation in response to cellular stress signals. promoting cell proliferation and survival. MDM2 also promotes cell cycle progression and contributes to the regulation of DNA repair processes. Several human tumor types have been shown to express increased levels of MDM2, including sarcoma, breast cancer, ovarian cancer, and glioblastoma, further supporting the role of MDM2 as an oncoprotein by promoting tumorigenesis through inactivation of the p53 tumor suppressor."}]}]}