eIF4A controls translation of estrogen receptor alpha and is a therapeutic target in advanced breast cancer

J Jacob A. Boyer (Ludwig Institute for Cancer Research, Princeton Branch, Princeton University) E Ezra Y. Rosen (Department of Medicine, Memorial Sloan Kettering Cancer Center) M Malvika Sharma (Program in Molecular Pharmacology, Department of Medicine, Memorial Sloan Kettering Cancer Center) M Madeline A. Dorso (Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center) N Nicholas Mai (Department of Medicine, Memorial Sloan Kettering Cancer Center) C Corina Amor (Louis V. Gerstner Jr. Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center) J Jason M. Reiter (Program in Molecular Pharmacology, Department of Medicine, Memorial Sloan Kettering Cancer Center) R Ram Kannan (Department of Cancer Biology and Genetics, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center) S Sunyana Gadal (Program in Molecular Pharmacology, Department of Medicine, Memorial Sloan Kettering Cancer Center) J Jianing Xu (Program in Molecular Pharmacology, Department of Medicine, Memorial Sloan Kettering Cancer Center) M Matthew Miele (Microchemistry and Proteomics Core Facility, Memorial Sloan Kettering Cancer Center) Z Zhuoning Li X Xiaoping Chen Q Qing Chang (Antitumor Assessment Core Facility, Memorial Sloan Kettering Cancer Center) F Fresia Pareja S Stephan Worland (Department of Cancer Biology, eFFECTOR Therapeutics, Inc.) D Douglas Warner (Department of Cancer Biology, eFFECTOR Therapeutics, Inc.) S Sam Sperry (Department of Cancer Biology, eFFECTOR Therapeutics, Inc.) G Gary G. Chiang (Department of Cancer Biology, eFFECTOR Therapeutics, Inc.) P Peggy A. Thompson (Department of Cancer Biology, eFFECTOR Therapeutics, Inc.) G Guangli Yang O Ouathek Ouerfelli A Alexander Drilon (Department of Medicine, Memorial Sloan Kettering Cancer Center) E Elisa de Stanchina H Hans-Guido Wendel (Department of Cancer Biology and Genetics, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center) S Sarat Chandarlapaty N Neal Rosen (Program in Molecular Pharmacology, Department of Medicine, Memorial Sloan Kettering Cancer Center)

Abstract

Most breast cancers depend on hormone-stimulated estrogen receptor alpha (ER) activity and are sensitive to ER inhibition. Resistance can arise from activating mutations in the gene encoding ER ( ESR1 ) or from reactivation of downstream targets. Newer ER antagonists occasionally show efficacy but are largely ineffective as single agents in the long term. Here, we show that ER translation is eIF4E/cap-independent yet sensitive to inhibitors of the translation initiation factor eIF4A. EIF4A inhibition reduces the expression of ER and cell cycle regulators such as cyclin D1. This leads to growth suppression in ligand-independent breast cancer models, including those driven by ER mutants and fusion proteins. Efficacy is enhanced by adding the ER degrader, fulvestrant. The combination further lowers ER expression and blocks tumor growth in vitro and in vivo. In an early clinical trial (NCT04092673), the eIF4A inhibitor zotatifin was combined with either fulvestrant or fulvestrant plus CDK4 inhibitor, abemaciclib, in patients with acquired resistance to these agents. Multiple clinical responses including a handful of durable regressions were observed, with little toxicity. Thus, eIF4A inhibition could be useful for treating ER+ breast cancer resistant to other modalities.

Article Details

Volume / Issue Vol. 122, Issue 30
Published July 29, 2025
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (27)

J

Jacob A. Boyer

Ludwig Institute for Cancer Research, Princeton Branch, Princeton University

E

Ezra Y. Rosen

Department of Medicine, Memorial Sloan Kettering Cancer Center

M

Malvika Sharma

Program in Molecular Pharmacology, Department of Medicine, Memorial Sloan Kettering Cancer Center

M

Madeline A. Dorso

Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center

N

Nicholas Mai

Department of Medicine, Memorial Sloan Kettering Cancer Center

C

Corina Amor

Louis V. Gerstner Jr. Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center

J

Jason M. Reiter

Program in Molecular Pharmacology, Department of Medicine, Memorial Sloan Kettering Cancer Center

R

Ram Kannan

Department of Cancer Biology and Genetics, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center

S

Sunyana Gadal

Program in Molecular Pharmacology, Department of Medicine, Memorial Sloan Kettering Cancer Center

J

Jianing Xu

Program in Molecular Pharmacology, Department of Medicine, Memorial Sloan Kettering Cancer Center

M

Matthew Miele

Microchemistry and Proteomics Core Facility, Memorial Sloan Kettering Cancer Center

Z

Zhuoning Li

X

Xiaoping Chen

Q

Qing Chang

Antitumor Assessment Core Facility, Memorial Sloan Kettering Cancer Center

F

Fresia Pareja

S

Stephan Worland

Department of Cancer Biology, eFFECTOR Therapeutics, Inc.

D

Douglas Warner

Department of Cancer Biology, eFFECTOR Therapeutics, Inc.

S

Sam Sperry

Department of Cancer Biology, eFFECTOR Therapeutics, Inc.

G

Gary G. Chiang

Department of Cancer Biology, eFFECTOR Therapeutics, Inc.

P

Peggy A. Thompson

Department of Cancer Biology, eFFECTOR Therapeutics, Inc.

G

Guangli Yang

O

Ouathek Ouerfelli

A

Alexander Drilon

Department of Medicine, Memorial Sloan Kettering Cancer Center

E

Elisa de Stanchina

H

Hans-Guido Wendel

Department of Cancer Biology and Genetics, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center

S

Sarat Chandarlapaty

N

Neal Rosen

Program in Molecular Pharmacology, Department of Medicine, Memorial Sloan Kettering Cancer Center