product name PI-1840
Description: PI-1840 is a rapidly reversible (non-covalent) and selective chymotrypsin-like (CT-L) inhibitor with IC50 of 27 nM. PI-1840 exhibited excellent selectivity for CT-L over PGPH-L and T-L activities. In MDA-MB-468 human breast cancer cells, PI-1840 inhibited the CT-L activity with IC50 value of 0.37 μM and inhibited cell survival/proliferation. Also, PI-1840 exhibited 121-fold selectivity for the constitutive 20 S proteasome over the immunoproteasome with IC50 values of 18 and 2170 nM, respectively.
References: J Med Chem. 2013 May 23;56(10):3783-805; J Biol Chem. 2014 Apr 25;289(17):11906-15.
394.47
Formula
C22H26N4O3
CAS No.
1401223-22-0
Storage
-20℃ for 3 years in powder form
-80℃ for 2 years in solvent
Solubility (In vitro)
DMSO: 78 mg/mL (197.7 mM)
Water: <1 mg/mL
Ethanol: 33 mg/mL (83.7 mM)
Solubility (In vivo)
Synonyms
other peoduct :
| In Vitro |
In vitro activity: PI-1840 potently inhibits proteasomal CT-L activity with IC50 of 0.37 μM in intact human MDA-MB-468 cancer cells, and inhibits proliferation/survival of human MDA-MB-468 cells. In intact cancer cells, PI-1840 inhibits CT-L activity, induces the accumulation of proteasome substrates p27, Bax, and IκB-α, inhibits survival pathways and viability, and induces apoptosis. Kinase Assay: In the high-throughput screen, fluorogenic peptides are used as substrates to assay (at 10 μM) the 50,000 compounds library from ChemBridge for inhibitory activity against the CT-L proteolytic activity of the purified rabbit 20S proteasome. To test for selectivity for CT-L over T-L and PGPH-L the corresponding fluorogenic peptides are used. Briefly, 1 nM of purified 20S rabbit proteasome is incubated with 20 μM Suc-Leu-Leu-Val-Tyr-AMC for the CT-L activity, Bz-Val-Gly-Arg-AMC for the T-L activity, and benzyloxycarbonyl Z-Leu-Leu-Glu-AMC for the PGPH-L activity for 1 h at 37 °C in 100 μL of assay buffer (50 mM Tris-HCl, pH 7.6) with or without compound. After incubation, production of hydrolyzed 7-amido-4-methyl-coumarin (AMC) groups is measured using a WALLAC Victor2 1420 Multilabel Counter with an excitation filter of 355 nm and an emission filter of 460 nm. The amount of AMC released is within the linear range. Bortezomib is used as a positive control for IC50 determinations. To determine proteasome activity in whole cell, extracts (5 μg) from cultured cell lysate is used instead of 20S rabbit proteasome, and followed the same assay mentioned above. Cell Assay: MDA-MB-468 cells are plated in 96-well plates in 100 μL medium and allowed to attach overnight. Cells are then incubated for 120 h with varying concentrations of inhibitors. Media is aspirated and replaced with 100 μL complete media containing 1 mg/ml MTT and incubated for three hours at 37 °C in 5% CO2 humidified incubator. Media is then aspirated and DMSO is added. Cells are incubated for 10 min at room temperature while shaking, and the absorbance is determined at 540 nm using a μQuant spectrophotometric plate reader. The IC50 values are determined using equation under CT-L, T-L, PGPH-L proteolytic activity assays. |
|---|---|
| In Vivo | PI-1840 (150 mg/kg i.p.) inhibits the tumor growth in mice of MDA-MB-231 breast tumors. |
| Animal model | Nude mice bearing human breast cancer MDA-MB-231 xenografts |
| Formulation & Dosage | Dissolved in 30% 2-hydroxypropyl-β-cyclodextrin; 150 mg/kg; i.p. administration |
| References | J Med Chem. 2013 May 23;56(10):3783-805; J Biol Chem. 2014 Apr 25;289(17):11906-15. |
