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

MDM-2/p53

MDM-2/p53

Related Products

PDF 0.55 MB

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-117857
    MRT00033659
    		p53 Activator 99.77%
    MRT00033659 is a potent broad-spectrum kinase inhibitor of CK1 (IC50=0.9 μM for CK1δ) and CHK1 (IC50=0.23 μM). MRT00033659, a pyrazolo-pyridine analogue, induces p53 pathway activation and E2F-1 destabilisation.
    MRT00033659
  • HY-U00447
    PK11000
    		p53 Activator 99.56%
    PK11000 is an alkylating agent, and stabilizes the DNA-binding domain of both WT and mutant p53 proteins by covalent cysteine modification without compromising DNA binding. PK11000 has anti-tumor activities.
    PK11000
  • 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-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
  • HY-108636
    RETRA
    		p53 Activator 99.42%
    RETRA is a mutant p53-dependent activator of p73 that suppresses mutant p53-bearing cancer cells. RETRA increases the expression level of p73, and a release of p73 from the blocking complex with mutant p53, which produces tumor-suppressor effects.
    RETRA
  • HY-N1931
    Epifriedelanol
    		≥98.0%
    Epifriedelanol is a triterpenoid found in the root bark of Ulmus davidiana. Epifriedelanol induces apoptosis in DU145 cells. Epifriedelanol has antitumor and anti-inflammatory activities. Epifriedelanol inhibits cellular senescence in human primary cells.
    Epifriedelanol
  • HY-15035
    S-Diclofenac
    		Activator 99.20%
    S-Diclofenac (ACS 15) is a hybrid molecule of an H2S donor and the NSAID diclofenac. S-Diclofenac activates the p53 signaling pathway, and inhibits the activation of JNK. S-Diclofenac exhibits antioxidant and anti-inflammatory activities.
    S-Diclofenac
  • HY-U00442
    CTX1
    		MDM2 Inhibitor
    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-W034419
    STIMA-1
    		p53 Activator 99.94%
    STIMA-1 can stimulate mutant p53 DNA binding in vitro and induce expression of p53 target proteins and trigger apoptosis in mutant p53-expressing human tumor cells.
    STIMA-1
  • HY-15676A
    Idasanutlin (enantiomer)
    		Control 99.18%
    Idasanutlin enantiomer is the isomer of Idasanutlin (HY-15676), and can be used as an experimental control. Idasanutlin (RG7388) is a potent and selective MDM2 antagonist, inhibiting p53-MDM2 binding, with an IC50 of 6 nM.
    Idasanutlin (enantiomer)
  • HY-108637A
    PhiKan 083 hydrochloride
    		p53 Activator 99.27%
    PhiKan 083 hydrochloride is a carbazole derivative, which binds to the surface cavity and stabilizes Y220C (a p53 mutant), with a Kd of 167 μM, and a relative binding affinity (Kd) of 150 μM in Ln229 cells.
    PhiKan 083 hydrochloride
  • HY-132595
    Teprasiran
    		p53 Inhibitor
    Teprasiran (QPI-1002) is a small interfering RNA that temporarily inhibits p53-mediated cell death that underlies acute kidney injury (AKI).
    Teprasiran
  • HY-P2096
    Hexapeptide-11
    		Inhibitor 99.52%
    Hexapeptide-11 is a bioactive peptide with anti-aging effect. Hexapeptide-11 protects fibroblasts against oxidative stress-mediated premature cellular senescence by mediating a downregulation of cellular proteins, such as ataxia telangiectasia mutated (ATM) and p53 .
    Hexapeptide-11
  • HY-P3508A
    PNC-27 acetate
    		99.32%
    PNC-27 acetate, a chimeric p53-penetratin peptide binds to HDM-2 in a p53 peptide-like structure, induces selective membrane-pore formation and leads to cancer cell lysis. PNC-27 acetate is an anticancer peptide. PNC-27 acetate can be used in acute myeloid leukemia research.
    PNC-27 acetate
  • HY-111550
    Bragsin2
    		Inhibitor 99.85%
    Bragsin2 is a potent, selective and noncompetitive nucleotide exchange factor BRAG2 inhibitor, with an IC50 of 3 μM. Bragsin2 binds at the interface between the PH domain of BRAG2 and the lipid bilayer, leads BRAG2 unable to activate lipidated Arf GTPase. Bragsin2 affects breast cancer stem cells.
    Bragsin2
  • HY-145937
    PK9327
    		Modulator 98.50%
    PK9327 is a small-molecule stabilizer targeting cavity-creating p53 cancer mutations.
    PK9327
  • HY-128553
    Antineoplaston A10
    		Activator 99.84%
    Antineoplaston A10 is an antineoplaston that inhibits the growth of human hepatoma cells by inducing apoptosis. Antineoplaston A10 can be used in the study of liver cancer and breast cancer.
    Antineoplaston A10
  • HY-19339
    Tenovin-3
    		p53 Activator ≥98.0%
    Tenovin-3 is a p53 activator.
    Tenovin-3
  • HY-148404
    p53 Activator 5
    		Activator 98.43%
    p53 Activator 5 (compound 134A) is a potent p53 activator with a SC150 value of <0.05 mM. p53 Activator 5 can bind to mutant p53 and restore the ability of the p53 mutant to bind DNA. p53 Activator 5 shows anti-tumor activity. p53 Activator 5 is a click chemistry reagent, it contains an Alkyne group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups.
    p53 Activator 5
Cat. No. Product Name / Synonyms Application Reactivity
All Rights Reserved.
Download MDM-2/p53 Signaling Pathway Map.

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.