Discovery of a Small-Molecule Degrader of Bromodomain and Extra-Terminal (BET) Proteins with Picomolar Cellular Potencies and Capable of Achieving Tumor Regression

Overview

Journal J Med Chem

Publisher American Chemical Society

Specialty Chemistry

Date 2017 Mar 25

PMID 28339196

Citations 126

Authors

Bing Zhou

Jiantao Hu

Fuming Xu

Zhuo Chen

Longchuan Bai

Ester Fernandez-Salas

Mei Lin

Liu Liu

Chao-Yie Yang

Yujun Zhao

Donna McEachern

Sally Przybranowski

Bo Wen

Duxin Sun

Shaomeng Wang

Affiliations

Soon will be listed here.

Abstract

The bromodomain and extra-terminal (BET) family proteins, consisting of BRD2, BRD3, BRD4, and testis-specific BRDT members, are epigenetic "readers" and play a key role in the regulation of gene transcription. BET proteins are considered to be attractive therapeutic targets for cancer and other human diseases. Recently, heterobifunctional small-molecule BET degraders have been designed based upon the proteolysis targeting chimera (PROTAC) concept to induce BET protein degradation. Herein, we present our design, synthesis, and evaluation of a new class of PROTAC BET degraders. One of the most promising compounds, 23, effectively degrades BRD4 protein at concentrations as low as 30 pM in the RS4;11 leukemia cell line, achieves an IC value of 51 pM in inhibition of RS4;11 cell growth and induces rapid tumor regression in vivo against RS4;11 xenograft tumors. These data establish that compound 23 (BETd-260/ZBC260) is a highly potent and efficacious BET degrader.

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