Catalog No.S7304

For research use only.

CPI-203 is a potent BET bromodomain inhibitor with IC50 of 37 nM for BRD4.

CPI-203 Chemical Structure

CAS No. 1446144-04-2

Selleck's CPI-203 has been cited by 13 publications

Purity & Quality Control

Choose Selective Epigenetic Reader Domain Inhibitors

Biological Activity

Description CPI-203 is a potent BET bromodomain inhibitor with IC50 of 37 nM for BRD4.
IL-6 [1]
(Cell-based assay)
BRD4 [1]
(Cell-free assay)
MYC [1]
(Cell-based assay)
30 nM 37 nM 99 nM
In vitro

CPI203 inhibits BRD4 in vitro and in cells, while does not affect BRD4 kinase activity in vitro. [1] CPI203 exerts a cytostatic effect in all the 9 MCL cell lines analyzed with GI50 ranging from 0.06 to 0.71 μM, with low cytotoxicity in normal PBMCs from healthy donors. Furthermore, lenalidomide and CPI203, by targeting IRF4 and MYC, efficiently activates the cell death program in MCL cells resistant to bortezomib. [2]

In vivo BRD4 mediates CTD Ser2 phosphorylation in vivo. [1] In REC-1 tumor-bearing mice, the combination of lenalidomide with CPI203 (2.5 mg/kg i.p.) synergistically augments the antitumoral properties of each single agent via the abrogation of MYC and IRF4 expression and the induction of apoptosis. [2]

Protocol (from reference)

Kinase Assay:


  • BRD4 α-screen assay:

    The BRD4 α-screen assay is a proximity-based assay using a tetraacteylated H4 peptide and the isolated bromodomain 1 of human BRD4. IC50 values are calculated using a 10-point serial dilution of BET inhibitor.

Cell Research:


  • Cell lines: 2 PBMC cultures from healthy donors and 9 MCL cell lines (Granta-519, JVM-2, UPN1, Z-138, JeKo-1, ZBR, JBR, Mino, REC-1 cells)
  • Concentrations: 10 μM
  • Incubation Time: 72 hours
  • Method:

    MCL primary cells and cell lines are incubated as indicated with lenalidomide and/or CPI203. MTT is added for 2-6 additional hours before spectrophotometric measurement. Each measurement is made in triplicate. Values are represented using untreated control cells. The GI50 is calculated as the concentration that produced 50 % growth inhibition. Combination indexes (CIs) are calculated by using the Calcusyn software version 2.0. The interaction between two drugs is considered synergistic when CI <1.

Animal Research:


  • Animal Models: REC-1 tumor-bearing mice
  • Dosages: 2.5 mg/kg twice daily
  • Administration: i.p

Solubility (25°C)

In vitro

DMSO 79 mg/mL warmed
(197.54 mM)
Ethanol 5 mg/mL
(12.5 mM)
Water Insoluble

Chemical Information

Molecular Weight 399.90


CAS No. 1446144-04-2
Storage 3 years -20°C powder
2 years -80°C in solvent
Smiles CC1=C(SC2=C1C(=NC(C3=NN=C(N32)C)CC(=O)N)C4=CC=C(C=C4)Cl)C

In vivo Formulation Calculator (Clear solution)

Step 1: Enter information below (Recommended: An additional animal making an allowance for loss during the experiment)

mg/kg g μL

Step 2: Enter the in vivo formulation (This is only the calculator, not formulation. Please contact us first if there is no in vivo formulation at the solubility Section.)

% DMSO % % Tween 80 % ddH2O

Calculation results:

Working concentration: mg/ml;

Method for preparing DMSO master liquid: mg drug pre-dissolved in μL DMSO ( Master liquid concentration mg/mL, Please contact us first if the concentration exceeds the DMSO solubility of the batch of drug. )

Method for preparing in vivo formulation: Take μL DMSO master liquid, next addμL PEG300, mix and clarify, next addμL Tween 80, mix and clarify, next add μL ddH2O, mix and clarify.

Method for preparing in vivo formulation: Take μL DMSO master liquid, next add μL Corn oil, mix and clarify.

Note: 1. Please make sure the liquid is clear before adding the next solvent.
2. Be sure to add the solvent(s) in order. You must ensure that the solution obtained, in the previous addition, is a clear solution before proceeding to add the next solvent. Physical methods such
as vortex, ultrasound or hot water bath can be used to aid dissolving.

Molarity Calculator

Mass Concentration Volume Molecular Weight

Tech Support

Answers to questions you may have can be found in the inhibitor handling instructions. Topics include how to prepare stock solutions, how to store inhibitors, and issues that need special attention for cell-based assays and animal experiments.

Handling Instructions

Tel: +1-832-582-8158 Ext:3
If you have any other enquiries, please leave a message.

* Indicates a Required Field

Please enter your name.
Please enter your email. Please enter a valid email address.
Please write something to us.
Tags: buy CPI-203 | CPI-203 supplier | purchase CPI-203 | CPI-203 cost | CPI-203 manufacturer | order CPI-203 | CPI-203 distributor