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-15510
    Tenovin-6
    p53 Activator 98.33%
    Tenovin-6, an analog of Tenovin-1 (HY-13423), is an activator of p53 transcriptional activity. Tenovin-6 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 also inhibits dihydroorotate dehydrogenase (DHODH).
    Tenovin-6
  • HY-108639
    MIRA-1
    p53 Activator 99.76%
    MIRA-1 is a maleimide analogue. MIRA-1 can induce apoptosis in mutant p53 cells via restoration of p53-dependent transcriptional transactivation. MIRA-1 has anticancer activity.
    MIRA-1
  • HY-120373
    MB710
    98.76%
    MB710, an aminobenzothiazole derivative, is a stabilizer of oncogenic p53 mutation Y220C. MB710 binds tightly to the Y220C pocket and stabilizes p53-Y220C, with a Kd of 4.1 μM. MB710 shows anticancer activity in p53-Y220C cell lines.
    MB710
  • HY-101666
    HBX 41108
    99.61%
    HBX 41108 is an inhibitor of ubiquitin-specific protease 7 (USP7) with an IC50 of 424 nM. HBX 41108 inhibits USP7-mediated p53 deubiquitination to stabilize p53 and inhibits cancer cell growth. BX 41108 can be used in cancer and diabetes research.
    HBX 41108
  • 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-17493
    MI-773
    MDM2 Inhibitor 98.08%
    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-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-P0121
    ReACp53
    p53 Activator 99.87%
    ReACp53 could inhibit p53 amyloid formation and rescue p53 function in cancer cell lines.
    ReACp53
  • HY-14714
    NSC-207895
    p53 Activator 98.97%
    NSC-207895 (XI-006), a DNA damaging agent, is an anticancer agent and p53 activator.
    NSC-207895
  • HY-B0263
    Thiabendazole
    99.72%
    Thiabendazole is an orally available benzimidazole fungicide with repellent and anticancer activities. Thiabendazole can result in developmental malformations. Thiabendazole can be used for modeling.
    Thiabendazole
  • HY-137864
    Amifostine thiol
    p53 Activator
    Amifostine thiol (WR-1065) is an active metabolite of the cytoprotector Amifostine (HY-B0639). Amifostine thiol is a cytoprotective agent with radioprotective abilities. Amifostine thiol activates p53 through a JNK-dependent signaling pathway.
    Amifostine thiol
  • HY-13423
    Tenovin-1
    p53 Activator 99.88%
    Tenovin-1, a p53 activator, protects p53 from MDM2-mediated degradation. Tenovin-1 acts through inhibition of the protein-deacetylating activities of SirT1 and SirT2. Tenovin-1 is also a dihydroorotate dehydrogenase (DHODH) inhibitor.
    Tenovin-1
  • HY-16999
    RO8994
    MDM2 Inhibitor 99.62%
    RO8994 is a highly potent and selective MDM2 inhibitor with IC50 of nM (HTRF binding assay) and 20 nM (MTT proliferation assay).
    RO8994
  • HY-19726
    NSC59984
    p53 Activator 99.74%
    NSC59984 induces mutant p53 protein degradation via MDM2 and the ubiquitin-proteasome pathway. NSC59984 acts by targeting GOF-mutant p53 and stimulates p73 to restore the p53 pathway signaling.
    NSC59984
  • HY-B0774
    Seratrodast
    Inhibitor 98.86%
    Seratrodast (AA 2414), an orally active antiasthmatic agent, is a thromboxane A2 receptor (TP) antagonist and ferroptosis inhibitor. Seratrodast reduces lipid ROS production, modulates the systemic xc-/GSH/GPX4 axis, and inhibits JNK phosphorylation and p53 expression. Seratrodast exhibits anti-asthmatic and anti-epileptic activity.
    Seratrodast
  • HY-122578
    P53R3
    p53 Inhibitor 99.94%
    P53R3 is a potent p53 reactivator and restores sequence-specific DNA binding of p53 hot spot mutants, including p53R175H, p53R248W and p53R273H. P53R3 induces p53-dependent antiproliferative effects with much higher specificity than PRIMA-1. P53R3 enhances the recruitment of wild-type p53 and p53M237I to several target gene promoters. P53R3 strongly enhances the mRNA, total protein and cell surface expression of the death receptor death receptor 5 (DR5). P53R3 is used for cancer research.
    P53R3
  • HY-P4157
    FOXO4-DRI
    Inhibitor 99.87%
    FOXO4-DRI is a cell-permeable peptide antagonist that blocks the interaction of FOXO4 and p53. FOXO4-DRI is a senolytic peptide that induces apoptosis of senescent cells.
    FOXO4-DRI
  • HY-W042191
    Oxychlororaphine
    Inducer 98.90%
    Oxychloroaphine could be isolated from the bacterium Pantoea agglomerans naturally present in soil. Oxychloroaphine has broad-spectrum antifungal activity. Oxychloroaphine has cytotoxicity in a dose-dependent manner and induces apoptosis. Oxychloroaphine can be used in research of cancer.
    Oxychlororaphine
  • 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-15869
    Inauhzin
    p53 Activator 99.49%
    Inauhzin is a dual SirT1/IMPDH2 inhibitor, and acts as an activator p53, used in the research of cancer.
    Inauhzin
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.