EGFR (IC50 = 8 μM); ErbB2 (IC50 = 49 nM); ErbB3 (IC50 = 52 nM); ErbB4 (IC50 = 52 nM)

At an IC50 of 13 nM, PD158780 inhibits the autophosphorylation of the EGF receptor in human epidermoid carcinoma A431. PD158780 exhibits a high degree of specificity towards the EGF receptor in Swiss 3T3 fibroblasts. It blocks the processes that are dependent on EGF, such as receptor autophosphorylation and thymidine incorporation, at low nanomolar concentrations. Conversely, it is necessary at micromolar levels for processes that are dependent on platelet-derived growth factor and basic fibroblast growth factor. With an IC50 of 49 and 52 nM, respectively, PD158780 suppresses heregulin-stimulated phosphorylation in SK-BR-3 and MDAMB-453 breast tumors, suggesting that the substance is effective against additional EGF receptor family members [1].

PD158780 exhibits anti-clonogenicity activity in a variety of breast tumor types with unique expression patterns of the ErbB family. PD158780, whether given intraperitoneally or orally, exhibits a good therapeutic impact on A431 epidermoid carcinoma. When human EGFR is transfected into mouse fibroblasts, PD158780 has quantifiably important effects. At isotoxic dose levels, PD158780 has notable therapeutic effects on estrogen-dependent MCF-7 breast cancer [1].

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In vivo intrahippocampal injection of the ErbB inhibitor, PD158780, impairs mGluRI-LTD at CA3-CA1 synapses and affects the exploratory behavior in the object recognition test. [2]

The enzymatic reaction is conducted in 96-well filter plates with a final volume of 0.1 mL. The reaction mixture consists of 20 mM HEPES (pH 7.4), 50 μM sodium vanadate, 40 mM magnesium chloride, 10 μM ATP (including 0.5 μCi of [³²P]ATP), 20 μg of polyglutamic acid/tyrosine, 1 ng of EGF receptor tyrosine kinase, and varying concentrations of the inhibitor PD158780 and/or ATP. All components except ATP are first added to the wells, followed by a 10-minute pre-incubation with shaking at 25°C. The reaction is initiated by adding [³²P]ATP, and the plate is incubated with shaking at 25°C for an additional 10 minutes. The reaction is stopped by adding 0.1 mL of 20% trichloroacetic acid (TCA), and the plate is chilled at 4°C for at least 15 minutes to ensure substrate precipitation. Finally, the wells are washed five times with 0.125 mL of 10% TCA, and [³²P] incorporation is measured[1].

All cell lines are cultured as monolayers in a 1:1 mixture of DMEM/F12 supplemented with 10% fetal bovine serum. For growth inhibition assays, serial dilutions of the test compound (PD158780) in 10 μL are dispensed into 24-well plates, followed by the addition of cells suspended in 2 mL of medium. The plates are then incubated for 72 hours at 37°C in a humidified environment. After incubation, cell growth is quantified by direct cell counting[1].

On day 0, tumor fragments were subcutaneously implanted into the right axillary region of mice. PD158780 was then administered via intraperitoneal injection or oral gavage. Tumor progression was subsequently monitored[1].

[1]. Biochemical and antiproliferative properties of 4-[ar(alk)ylamino]pyridopyrimidines, a new chemical class of potent and specific epidermal growth factor receptor tyrosine kinase inhibitor. Biochem Pharmacol. 1997 Oct 15;54(8):877-87.

[2]. Neuregulin 1/ErbB signalling modulates hippocampal mGluRI-dependent LTD and object recognition memory. Pharmacol Res. 2018 Apr:130:12-24.

PD158780 is a pyridopyrimidine compound with the structure pyrido[3,4-d]pyrimidine-4,6-diamine, wherein the amino groups at positions 4 and 6 are replaced by m-bromophenyl and methyl groups, respectively. It is a potent, cell-membrane-penetrating, reversible ATP-competitive EGFR tyrosine kinase activity inhibitor (IC50 values for EGFR, ErbB2 (HER2), and Erb4 (HER4) are 0.008, 49, and 52 nM, respectively). It does not inhibit FGF or PDGF-mediated tyrosine phosphorylation. PD158780 induces G1 phase cell cycle arrest in MCF10A cells and inhibits the proliferation of A431 human epidermal carcinoma cells. It possesses antitumor activity and is also an EC2.7.10.1 (receptor protein tyrosine kinase) inhibitor. It is a pyridopyrimidine compound, belonging to the secondary amine class, bromobenzene class, diamine class, and aromatic amine class. Tyrosine kinase inhibitors PD 69896, 153717, and 158780 belong to the 4-[aryl(alkyl)amino]pyridopyrimidine class and their enzymatic properties, target specificity, and anti-tumor cell proliferation effects have been characterized. These compounds are ATP-competitive inhibitors of purified epidermal growth factor (EGF) receptor tyrosine kinase and inhibit EGF receptor autophosphorylation in A431 human epidermal-like cancer cells, with IC50 values of 2085, 110, and 13 nM, respectively. Inhibition occurs immediately after cell exposure to these compounds; however, the recovery of receptor autophosphorylation activity after washing away the compounds depends on the inhibitory efficacy. Therefore, activity is fully restored immediately after removal of PD 69896, but recovery takes 8 hours after exposure to PD 158780. PD 158780 exhibits high specificity for EGF receptors in Swiss 3T3 fibroblasts, inhibiting EGF-dependent receptor autophosphorylation and thymidine incorporation even at low nanomolar concentrations, while micromolar concentrations are required to inhibit platelet-derived growth factor and basic fibroblast growth factor-dependent processes. PD 158780 inhibits heregulin-stimulated phosphorylation in SK-BR-3 and MDA-MB-453 breast cancer cells, with IC50 values of 49 nM and 52 nM, respectively, indicating that this compound is also active against other members of the EGF receptor family. The antiproliferative effect of this series of compounds on A431 cells is entirely correlated with its inhibitory efficacy on EGF receptor autophosphorylation. PD 158780 reduces colony formation in soft agar of fibroblasts transformed by EGF, EGF receptor, or neu oncogenes, but has no effect on ras or raf-transformed fibroblasts, further demonstrating its high specificity. In addition, the compound was active against the clonogenesis of several breast tumors with different erbB family expression patterns, indicating that it has an anticancer effect on tumors expressing these receptors. [1]

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Neurotrophic factor neuroregulatory protein (NRG) and its receptor ErbB tyrosine kinase regulate neurotransmission, synaptic plasticity and cognitive function, and their alterations are associated with a variety of neuropsychiatric disorders. In animal models of neuropsychiatric disorders, group I metabolotropic glutamate receptor (mGluRI)-dependent mechanisms are also altered, especially mGluRI-induced long-term glutamatergic inhibition (mGluRI-LTD), a form of synaptic plasticity that plays a key role in learning and memory. Despite this evidence, the potential link between the NRGs/ErbB signaling pathway and mGluRI-LTD has never been considered. This study aims to verify whether the NRGs/ErbB signaling pathway modulates the function of mGluRI in the hippocampus, thereby controlling the excitability and synaptic plasticity of CA1 pyramidal neurons and mGluRI-dependent behavior. We investigated the functional interaction between the NRG1/ErbB signaling pathway and mGluRI in hippocampal CA1 pyramidal neurons by analyzing the effects of pharmacological regulation of the NRG1/ErbB signaling pathway on pyramidal neuronal excitability and mGluRI agonist-induced CA3-CA1 synaptic LTD. Furthermore, we validated the involvement of the ErbB signaling pathway in mGluRI-dependent learning by evaluating the behavior of mice after intrahippocampal injection of a pan-ErbB inhibitor in a mouse object recognition test (a hippocampal mGluRI-dependent learning task). We found that NRG1 enhanced the mGluRI-dependent function of CA3-CA1 synaptic pyramidal neuronal excitability and synaptic plasticity. Moreover, the endogenous ErbB signaling pathway itself regulates the excitability and LTD of CA1 pyramidal neurons via mGluRI, as ErbB inhibition reduces mGluRI-induced neuronal excitability and mGluRI-LTD. Intrahippocampal injection of the ErbB inhibitor PD158780 in mice impaired the mGluRI-LTD of the CA3-CA1 synapse and affected exploratory behavior in the object recognition test. Therefore, our findings suggest that NRG1/ErbB signaling plays a crucial role in regulating hippocampal mGluRI-dependent synapses and cognitive function, and its alterations may contribute to the pathogenesis of various brain diseases. [2]

C14H12BRN5

330.1826

329.028

C, 50.93; H, 3.66; Br, 24.20; N, 21.21

171179-06-9

4707

Light yellow to yellow solid powder

1.611g/cm3

499.6ºC at 760 mmHg

176 °C

255.9ºC

4.1E-10mmHg at 25°C

1.768

3.718

2

5

3

20

316

0

CNC1=NC=C2C(=C1)C(=NC=N2)NC3=CC(=CC=C3)Br

KFHMLBXBRCITHF-UHFFFAOYSA-N

InChI=1S/C14H12BrN5/c1-16-13-6-11-12(7-17-13)18-8-19-14(11)20-10-4-2-3-9(15)5-10/h2-8H,1H3,(H,16,17)(H,18,19,20)

4-N-(3-bromophenyl)-6-N-methylpyrido[3,4-d]pyrimidine-4,6-diamine

PD 158780; 171179-06-9; PD158,780; pd 158,780; N4-(3-bromophenyl)-N6-methylpyrido[3,4-d]pyrimidine-4,6-diamine; PD-158,780; AC1L1IRV; CHEBI:92843; DTXSID20274443; PD158780; PD-158780.

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~16.67 mg/mL (~50.49 mM)

Solubility in Formulation 1: 1.67 mg/mL (5.06 mM) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 16.7 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: 1.67 mg/mL (5.06 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 16.7 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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 (Please use freshly prepared in vivo formulations for optimal results.)