Toggle Main Menu Toggle Search

Open Access padlockePrints

AZD5153: a novel bivalent BET bromodomain inhibitor highly active against hematologic malignancies

Lookup NU author(s): Professor Mike Waring

Downloads


Licence

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).


Abstract

The bromodomain and extraterminal (BET) protein BRD4 regulates gene expression via recruitment of transcriptional regulatory complexes to acetylated chromatin. Pharmacological targeting of BRD4 bromodomains by small-molecule inhibitors has proven to be an effective means to disrupt aberrant transcriptional programs critical for tumor growth and/or survival. Herein, we report AZD5153, a potent, selective, and orally available BET/BRD4 bromodomain inhibitor possessing a bivalent binding mode. Unlike previously described monovalent inhibitors, AZD5153 ligates two bromodomains in BRD4 simultaneously. The enhanced avidity afforded through bivalent binding translates into increased cellular and antitumor activity in preclinical hematologic tumor models. In vivo administration of AZD5153 led to tumor stasis or regression in multiple xenograft models of Acute Myeloid Leukemia (AML), Multiple Myeloma (MM), and Diffuse Large B-cell Lymphoma (DLBCL). The relationship between AZD5153 exposure and efficacy suggests that prolonged BRD4 target coverage is a primary efficacy driver. AZD5153 treatment markedly impacts transcriptional programs of MYC, E2F, and mTOR. Of note, mTOR pathway modulation is associated with cell line sensitivity to AZD5153. Transcriptional modulation of MYC and HEXIM1 was confirmed in AZD5153-treated human whole blood, thus supporting their use as clinical pharmacodynamic biomarkers. This report establishes AZD5153 as a highly potent, orally available BET/BRD4 inhibitor and provides rationale for clinical development in hematologic malignancies.


Publication metadata

Author(s): Rhyasen GW, Hattersley M, Yao Y, Dulak A, Wang W, Petteruti P, Dale I, Boiko S, Cheung T, Zhang J, Wen S, Castriotta L, Lawson D, Collins M, Bao L, Ahdesmaki MJ, Walker G, O'Connor G, Yeh T, Rabow AA, Dry J, Reimer C, Lyne P, Mills GB, Fawell S, Waring MJ, Zinda M, Clark E, Chen H

Publication type: Article

Publication status: Published

Journal: Molecular Cancer Therapeutics

Year: 2016

Volume: 15

Issue: 11

Pages: 2563-2574

Print publication date: 01/11/2016

Online publication date: 29/08/2016

Acceptance date: 15/08/2016

Date deposited: 30/08/2016

ISSN (print): 1535-7163

ISSN (electronic): 1538-8514

Publisher: American Association for Cancer Research

URL: http://dx.doi.org/10.1158/1535-7163.MCT-16-0141

DOI: 10.1158/1535-7163.MCT-16-0141


Altmetrics

Altmetrics provided by Altmetric


Share