Case Report: 7-Ethyl-10-Hydroxycamptothecin, a DNA Topoisomerase I Inhibitor, Performs BRD4 Inhibitory Activity and Inhibits Human Leukemic Cell Growth

Overview

Journal Front Pharmacol

Date 2021 May 17

PMID 33995089

Authors

Airong Wang

Lingling Li

Mengya Li

Shujuan Wang

Chong Wang

Affiliations

Soon will be listed here.

Abstract

7-Ethyl-10-hydroxycamptothecin (SN-38) is an active metabolite of CPT-11, which can inhibit DNA topoisomerase I, DNA synthesis and cause frequent DNA single-strand breaks. In our study, SN-38 was characterized as a potent and reversible BRD4 inhibitor [IC = 660.2 nM against BRD4 (BD1) and IC = 547.7 nM against BRD4 (BD2)] in biochemical assay using drug repurposing strategy. Additional cellular assay suggested that SN-38 can bind BRD4 in human leukemic cell K562 and inhibit cell growth with IC = 0.2798 μM in a BRD4 dependent manner partially. Additionally, mechanism study indicated that SN-38 can induce the accumulation of BRD4 substrate c-Myc and cleavage of caspase 3. In sum, our findings identified BRD4 as a new target of SN-38 and reveals SN-38 as a modifier of histone acetylation reader for the first time, which may provide a new insight for further optimization of dual target inhibitor.

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