1. Signaling Pathways
  2. Apoptosis
  3. MDM-2/p53

MDM-2/p53

The p53 tumor suppressor is a principal mediator of growth arrest, senescence, and apoptosis in response to a broad array of cellular damage. p53 is a short-lived protein that is maintained at low, often undetectable, levels in normal cells. Under stress conditions, the p53 protein accumulates in the cell, binds in its tetrameric form to p53-response elements and induces the transcription of various genes.

MDM-2 is transcriptionally activated by p53 and MDM-2, in turn, inhibits p53 activity in several ways. MDM-2 binds to the p53 transactivation domain and thereby inhibits p53-mediated transactivation. MDM-2 also contains a signal sequence that is similar to the nuclear export signal of various viral proteins and, after binding to p53, it induces its nuclear export. As p53 is a transcription factor, it needs to be in the nucleus to be able to access the DNA; its transport to the cytoplasm by MDM-2 prevents this. Finally, MDM-2 is a ubiquitin ligase, so is able to target p53 for degradation by the proteasome.

In many tumors p53 is inactivated by the overexpression of the negative regulators MDM2 and MDM4 or by the loss of activity of the MDM2 inhibitor ARF. The pathway can be reactivated in these tumors by small molecules that inhibit the interaction of MDM2 and/or MDM4 with p53. Such molecules are now in clinical trials.

Cat. No. Product Name Effect Purity Chemical Structure
  • HY-130684
    MDM2-IN-1
    MDM2 Inhibitor 98.02%
    MDM2-IN-1 (Compound 30) is a synthetic MDM2-p53 interaction (MDM2) inhibitor and contains the trans-configuration. MDM2-IN-1 can be used for the study of osteosarcoma.
    MDM2-IN-1
  • HY-128841
    PROTAC MDM2 Degrader-2
    MDM2 Inhibitor
    PROTAC MDM2 Degrader-2 is an MDM2 PROTAC degrader. PROTAC MDM2 Degrader-2 can induce the self-ubiquitination and degradation of MDM2, thereby upregulating the level of p53 protein. PROTAC MDM2 Degrader-2 has anti-tumor activity and can be used in the study of cancer. (Blue: MDM2 ligand (HY-128836); Black: linker (HY-128833))
    PROTAC MDM2 Degrader-2
  • HY-145785A
    ADH-6 TFA
    Modulator 99.91%
    ADH-6 TFA is a tripyridylamide compound. ADH-6 abrogates self-assembly of the aggregation-nucleating subdomain of mutant p53 DBD. ADH-6 TFA targets and dissociates mutant p53 aggregates in human cancer cells, which restores p53's transcriptional activity, leading to cell cycle arrest and apoptosis. ADH-6 TFA has the potential for the research of cancer diseases.
    ADH-6 TFA
  • HY-134823
    MD-222
    MDM2 Inhibitor 99.81%
    MD-222 is the first-in-class highly potent PROTAC degrader of MDM2. MD-222 consists of ligands for Cereblon and MDM2. MD-222 induces rapid degradation of the MDM2 protein and activation of wild-type p53 in cells. MD-222 has anticancer effects.
    MD-222
  • HY-16664
    SJ-172550
    MDM2 Inhibitor 99.95%
    SJ-172550 is a small molecule inhibitor of MDMX; competes for the wild type p53 peptide binding to MDMX with an EC50 of 5 μM.
    SJ-172550
  • HY-17493
    MI-773
    MDM2 Inhibitor
    MI-773 is a potent MDM2-p53 protein‐protein interaction (PPI) inhibitor with high binding affinity against MDM2 (Kd=8.2 nM). MI-773 has antitumor activity.
    MI-773
  • HY-16999
    RO8994
    MDM2 Inhibitor 99.62%
    RO8994 (Compound 4) is an orally active, highly potent and selective spiroindolinone p53-MDM2 inhibitor with an IC50 value of 5 nM (HTRF binding assays) and 20 nM (MTT proliferation assays). RO8994 induces up-regulation of p53 expression and Apoptosis in wild-type p53 cancer cells. RO8994 also inhibits tumor growth in the tumor xenograft model.
    RO8994
  • HY-120149
    Inotodiol
    Activator 98.29%
    Inotodiol activates p53 signaling pathway, inhibits MMP-2/9, and exhibits antitumor activity in cancer cell HeLa. Inotodiol inhibits the generation of ROS and exhibits antioxidant and neuroprotective effects. Inotodiol inhibits the activation of MAPK and NF-κB signaling pathway, and exhibits anti-inflammatory activity. Inotodiol inhibits TLR-4 mediated TNF-α production (IC50s in BMMC and BMDM is 0.7 μM and 3.0 μM), inhibits the degranulation in mast cell, exhibits anti-allergic activity. Inotodiol is orally active.
    Inotodiol
  • HY-160922
    BAY 249716
    99.03%
    BAY 249716 stabilizes all three p53 protein variants. BAY 249716 also has antitubercular activity (IC90: <0.10 μg/mL for Tuberculosis).
    BAY 249716
  • HY-112128
    USP7-IN-3
    99.06%
    USP7-IN-3 (Compound 5) is an effective and selective allosteric inhibitor of ubiquitin-specific protease 7 (USP7). USP7-IN-3 can be used for research on acute lymphoblastic leukemia.
    USP7-IN-3
  • HY-120122
    PK7088
    99.11%
    PK7088 is a pyrazole and a specific peptide. PK7088 supports the reactivation of mutant p53 by converting it to a form exhibiting wild-type properties. PK7088 exhibit anticancer activity in cancer research.
    PK7088
  • HY-100383
    BH3I-1
    MDM2 Inhibitor 98.0%
    BH3I-1 is a Bcl-2 family antagonist, which inhibits the binding of the Bak BH3 peptide to Bcl-xL with a Ki of 2.4±0.2 μM in FP assay. BH3I-1 has a Kd of 5.3 μM against the p53/MDM2 pair.
    BH3I-1
  • HY-15510B
    Tenovin-6 Hydrochloride
    p53 Activator 98.88%
    Tenovin-6 Hydrochloride, an analog of Tenovin-1 (HY-13423), is an activator of p53 transcriptional activity. Tenovin-6 Hydrochloride inhibits the protein deacetylase activities of purified human SIRT1, SIRT2, and SIRT3 with IC50s of 21 μM, 10 μM, and 67 μM, respectively. Tenovin-6 Hydrochloride also inhibits dihydroorotate dehydrogenase (DHODH).
    Tenovin-6 Hydrochloride
  • HY-N0331
    Ziyuglycoside I
    p53 Activator 99.42%
    Ziyuglycoside I isolated from S. officinalis root, has anti-wrinkle activity, and increases the expression of type I collagen. Ziyuglycoside I could be used as an active ingredient for cosmetics. Ziyuglycoside I triggers cell cycle arrest and apoptosis mediated by p53, it can be a potential agent candidate for treating triple-negative breast cancer (TNBC).
    Ziyuglycoside I
  • HY-120086
    RO-5963
    MDM2 Inhibitor 98.19%
    RO-5963 is a dual p53-MDM2 and p53-MDMX inhibitor with IC50s of ~17 nM and ~24 nM, respectively.
    RO-5963
  • HY-U00442
    CTX1
    MDM2 Inhibitor 98.50%
    CTX1 is a p53 activator that overcomes HdmX-mediated p53 repression. CTX1 exhibits potent anti-cancer activity in a mouse acute myeloid leukemia (AML) model system.
    CTX1
  • HY-132595A
    Teprasiran sodium
    Teprasiran sodium is a small interfering RNA that temporarily inhibits p53-mediated cell death that underlies acute kidney injury (AKI).
    Teprasiran sodium
  • HY-156906
    UNC3474
    Inhibitor 98.15%
    UNC3474 is a small molecule ligand, binding with 53BP1. UNC3474 binds the aromatic methyl-lysine binding cage of 53BP1TT, with a dissociation constant (Kd) of 1.0 ± 0.3 μM. UNC3474 inhibits the recruitment of 53BP1 to DSBs by stabilizing a pre-existing autoinhibited state of 53BP1 in cells.
    UNC3474
  • HY-W013053
    Dibenz[a,h]anthracene
    98.0%
    Dibenz[a,h]anthracene (DBA) is a polycyclic aromatic hydrocarbon (PAH) of considerable tumorigenicity. Dibenz[a,h]anthracene results in DNA adduct formation leading to the activation of a DNA damage response. Dibenz[a,h]anthracene induces cell cycle arrest and apoptosis via both Tp53-dependent and Tp53-independent mechanisms.
    Dibenz[a,h]anthracene
  • HY-16138A
    Ivaltinostat formic
    Activator 98.26%
    Ivaltinostat (CG-200745) formic is an orally active, potent pan-HDAC inhibitor which has the hydroxamic acid moiety to bind zinc at the bottom of catalytic pocket. Ivaltinostat formic inhibits deacetylation of histone H3 and tubulin. Ivaltinostat formic induces the accumulation of p53, promotes p53-dependent transactivation, and enhances the expression of MDM2 and p21 (Waf1/Cip1) proteins. Ivaltinostat formic enhances the sensitivity of Gemcitabine-resistant cells to Gemcitabine (HY-16138) and 5-Fluorouracil (5-FU; HY-90006). Ivaltinostat formic induces apoptosis and has anti-tumour effects.
    Ivaltinostat formic
Cat. No. Product Name / Synonyms Application Reactivity

p53 is at the centre of biological interactions that translates stress signals into cell cycle arrest or apoptosis. Upstream signaling to p53 increases its level and activates its function as a transcription factor in response to a wide variety of stresses, whereas downstream components execute the appropriate cellular response. 

 

Cell Stress: p53 induction by acute DNA damage begins when DNA double-strand breaks trigger activation of ATM, a kinase that phosphorylates the CHK2 kinase, or when stalled or collapsed DNA replication forks recruit ATR, which phosphorylates CHK1. p53 is a substrate for both the ATM and ATR kinases, as well as for CHK1 and CHK2, which coordinately phosphorylate p53 to promote its stabilization. These phosphorylation events are important for p53 stabilization, as some of the modifications disrupt the interaction between p53 and its negative regulators MDM2 and MDM4. MDM2 and MDM4 bind to the transcriptional activation domains of p53, thereby inhibiting p53 transactivation function, and MDM2 has additional activity as an E3 ubiquitin ligase that causes proteasome-mediated degradation of p53. Phosphorylation also allows the interaction of p53 with transcriptional cofactors, which is ultimately important for activation of target genes and for responses such as cell cycle arrest, DNA repair, apoptosis and senescence. Non-receptor tyrosine kinase c-Abl can also be activated by DNA damage. Then the JNK/p38 is activated and leads to p53 activation[1][2]

 

Oncogenic signaling: The response to oncogene activation depends on the binding of ARF to MDM2. ARF is normally expressed at low levels in cells. Inappropriately increased E2F or Myc signals, stemming from oncogene activation, leads to the increased expression of ARF, which inhibits MDM2 by blocking its E3 ubiquitin ligase activity, uncoupling the p53-MDM2 interaction, thereby segregating it from nucleoplasmic p53[3].

 

The PI3K-Akt pathway activates MDM2 and increases the ubiquitination of p53. 

 

Reference:
[1]. Chène P, et al. Inhibiting the p53-MDM2 interaction: an important target for cancer therapy. Nat Rev Cancer. 2003 Feb;3(2):102-9.
[2]. Brown CJ, et al. Awakening guardian angels: drugging the p53 pathway. Nat Rev Cancer. 2009 Dec;9(12):862-73. 
[3]. Polager S, et al. p53 and E2f: partners in life and death. Nat Rev Cancer. 2009 Oct;9(10):738-48. doi: 10.1038/nrc2718.