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

MDM-2/p53 

p53 肿瘤抑制因子是响应多种细胞损伤而导致生长停滞、衰老和凋亡的主要介质。p53 是一种短寿命蛋白质,在正常细胞中维持在较低水平,通常无法检测到。在压力条件下,p53 蛋白在细胞中积累,以四聚体形式与 p53 反应元件结合并诱导各种基因的转录。

MDM-2 由 p53 转录激活,而 MDM-2 反过来以多种方式抑制 p53 活性。MDM-2 与 p53 转录激活域结合,从而抑制 p53 介导的转录激活。MDM-2 还包含类似于各种病毒蛋白的核输出信号的信号序列,在与 p53 结合后,它会诱导其核输出。由于 p53 是一种转录因子,它需要位于细胞核中才能接触 DNA; MDM-2 将其转运至细胞质可防止这种情况发生。最后,MDM-2 是一种泛素连接酶,因此能够靶向 p53 并由蛋白酶体降解。

在许多肿瘤中,p53 因负调节因子 MDM2 和 MDM4 的过度表达或 MDM2 抑制剂 ARF 的活性丧失而失活。这些肿瘤中的该通路可以通过抑制 MDM2 和/或 MDM4 与 p53 相互作用的小分子重新激活。此类分子目前正在临床试验中。

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-12287
    YH239-EE MDM2 Inhibitor 98.28%
    YH239-EE是YH239的乙酯形式,是p53-MDM2的拮抗剂、凋亡诱导剂。
    YH239-EE
  • HY-15676A
    Idasanutlin (enantiomer) Control 99.18%
    Idasanutlin enantiomer 是 Idasanutlin (HY-15676) 的异构体,可作为实验中的对照化合物。Idasanutlin (RG7388) 是一种有效,选择性的 MDM2 拮抗剂,能够抑制 p53-MDM2 的结合,IC50 值为 6 nM。
    Idasanutlin (enantiomer)
  • HY-156967
    BAY 1892005 Modulator 99.44%
    BAY 1892005 是 p53 蛋白的调节剂,作用于 p53 凝聚体,不会导致突变型 p53 再激活。
    BAY 1892005
  • HY-130437
    p-nitro-Pifithrin-α p53 Inhibitor
    p-nitro-Pifithrin-α 是一种细胞可渗透的 pifithrin-α 类似物,是一种有效的 p53 抑制剂。p-nitro-Pifithrin-α 抑制 HK-2 细胞中 p53 介导的 TGF-β1 表达。p-nitro-Pifithrin-α 可抑制寨卡病毒株引起的 caspase-3 的活化。p-nitro-Pifithrin-α 可减轻高脂肪饮食小鼠的脂肪变性和肝损伤。
    p-nitro-Pifithrin-α
  • HY-14967
    NSC 66811 p53 Activator 98.12%
    NSC 66811 是一个MDM2-p53 抑制剂,其结合到MDM2 的 Ki 值为 120 nM。
    NSC 66811
  • HY-161254
    ATPase-IN-3 Activator 99.89%
    ATPase-IN-3 (compound 6) 是一种 ATP 酶 (ATPase) 抑制剂。ATPase-IN-3 通过参与抗凋亡 (BCL-2) 和肿瘤抑制 (P53) 蛋白在乙醇性胃溃疡中发挥胃保护作用。
    ATPase-IN-3
  • HY-148402
    p53 Activator 3 Activator 98.35%
    p53 Activator 3 (compound 87A) 是一种有效的 p53 激活剂,SC150 值 <0.05 mM。p53 Activator 3 可以结合突变体 p53 并恢复 p53 突变体结合 DNA 的能力。p53 Activator 3 具有抗肿瘤活性。
    p53 Activator 3
  • HY-122753
    SLMP53-1 Activator 99.83%
    SLMP53-1 是一种具有良好抗肿瘤活性的野生型和突变型 p53 再激活剂。 SLMP53-1 介导癌细胞葡萄糖代谢的重编程。 SLMP53-1 减少血管生成,减少内皮细胞管的形成和血管内皮生长因子 (VEGF) 的表达水平。
    SLMP53-1
  • HY-116794
    SF5 Inhibitor 99.83%
    SF5 (2,2-Diphenylethyl isothiocyanate) 是一种萝卜硫素类似物。SF5 通过 JNK-p53-caspase 通路抑制细胞凋亡 (apoptosis)。SF5 可作为抗药物性急性肾脏疾病的新型肾保护剂。
    SF5
  • HY-148404
    p53 Activator 5 Activator 98.43%
    p53 Activator 5 (compound 134A) 是一种有效的 p53 激活剂,SC150 值 <0.05 mM。p53 Activator 5 可以结合突变体 p53 并恢复 p53 突变体结合 DNA 的能力。p53 Activator 5 具有抗肿瘤活性。
    p53 Activator 5
  • HY-156906
    UNC3474 Inhibitor 98.15%
    UNC3474 是一种小分子配体,与 53BP1 结合。UNC3474 结合 53BP1TT 的芳香族甲基赖氨酸结合笼,解离常数 (Kd) 为 1.0 ±0.3μM。UNC3474 通过稳定细胞中预先存在的 53BP1 自抑制状态来抑制 53BP1 向 DSB 的募集。
    UNC3474
  • HY-N12233
    Condurango glycoside A Activator
    Condurango glycoside A 是 p53 的激活剂。Condurango glycoside A 启动 ROS 生成,上调 p53 表达量。Condurango glycoside A 诱导 HeLa 细胞与 DNA 损伤相关的凋亡和过早衰老。
    Condurango glycoside A
  • HY-15954B
    NVP-CGM097 sulfate MDM2 Inhibitor 98.82%
    NVP-CGM097是有效,选择性的MDM2抑制剂;IC50值为1.7 nM。
    NVP-CGM097 sulfate
  • HY-103640
    Amifostine thiol dihydrochloride

    氨磷汀杂质2

    p53 Activator
    Amifostine thiol (WR-1065) dihydrochloride 可以保护正常组织免受某些癌症活性分子的毒性作用,并通过 JNK 依赖性信号通路激活 p53
    Amifostine thiol dihydrochloride
  • HY-145785
    ADH-6 Modulator
    ADH-6 是一种三吡啶酰胺化合物。ADH-6 消除了突变 p53 DBD 的聚集成核亚结构域的自组装。ADH-6 靶向并解离人类癌细胞中的突变 p53 聚集体,从而恢复 p53 的转录活性,导致细胞周期停滞和细胞凋亡 (apoptosis)。ADH-6 具有研究癌症疾病的潜力。
    ADH-6
  • HY-125858A
    MI-1061 TFA Inhibitor
    MI-1061 TFA 是一种有效的,口服可生物利用的,化学稳定性的 MDM2 (MDM2-p53 互作) 抑制剂 (IC50=4.4 nM; Ki=0.16 nM)。MI-1061 TFA 激活小鼠 SJSA-1 异种移植瘤组织中 p53 并诱导凋亡,具有抗肿瘤活性。
    MI-1061 TFA
  • HY-16138
    Ivaltinostat Activator
    Ivaltinostat (CG-200745) 是一种口服有效的泛 HDAC 抑制剂,具有异羟肟酸部分,可在催化袋底部结合锌。Ivaltinostat 抑制组蛋白 H3 和微管蛋白的脱乙酰作用。Ivaltinostat 诱导 p53 的积累,促进 p53 依赖性反式激活,并增强 MDM2 和 p21 (Waf1/Cip1) 蛋白的表达。Ivaltinostat 可增强 Gemcitabine 耐药细胞对 Gemcitabine (HY-16138) 和 5-Fluorouracil (5-FU; HY-90006) 的敏感性。Ivaltinostat 诱导凋亡并具有抗肿瘤作用。
    Ivaltinostat
  • HY-153767
    PK095 ≥98.0%
    PK095 是一种 p53 突变体稳定剂。PK095 可用于癌症研究。
    PK095
  • HY-P5910
    Azurin p28 peptide 99.40%
    Azurin p28 peptide 是一种可穿透肿瘤的抗肿瘤肽。Azurin p28 peptide 通过形成 p28:p53 复合物减少 p53 的蛋白酶体降解。Azurin p28 peptide 诱导细胞凋亡 (apoptosis) 或细胞周期停滞。Azurin p28 peptide 抑制 p53 阳性肿瘤生长。Azurin p28 peptide 通过抑制 VEGFR-2、FAK 和 Akt 磷酸化显示抗血管生成作用
    Azurin p28 peptide
  • HY-19339
    Tenovin-3 p53 Activator ≥98.0%
    Tenovin-3 是p53 的激活剂。
    Tenovin-3
目录号 产品名 / 同用名 应用 反应物种

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.