ZHX2 promotes HIF1α oncogenic signaling in triple-negative breast cancer
- The First Affiliated Hospital of Nanjing Medical University, China
- University of Texas Southwestern Medical Center, United States
- University of North Carolina School of Medicine, United States
- The University of Alabama at Birmingham, United States
- Shanghai Jiao Tong University School of Medicine, China
- The University of Texas Health Science Center at Houston McGovern Medical School, United States
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Taiwan
- The University of Texas Southwestern Medical Center, United States
- Department of Pathology, University of Texas Southwestern Medical Center, United States
- National Tsing Hua University, Taiwan
Abstract
Triple-negative breast cancer (TNBC) is an aggressive and highly lethal disease, which warrants the critical need to identify new therapeutic targets. We show that Zinc Fingers and Homeoboxes 2 (ZHX2) is amplified or overexpressed in TNBC cell lines and patients. Functionally, depletion of ZHX2 inhibited TNBC cell growth and invasion in vitro, orthotopic tumor growth and spontaneous lung metastasis in vivo. Mechanistically, ZHX2 bound with hypoxia inducible factor (HIF) family members and positively regulated HIF1a activity in TNBC. Integrated ChIP-Seq and gene expression profiling demonstrated that ZHX2 co-occupied with HIF1a on transcriptionally active promoters marked by H3K4me3 and H3K27ac, thereby promoting gene expression. Among the identified ZHX2 and HIF1a co-regulated genes, overexpression of AP2B1, COX20, KDM3A, or PTGES3L could partially rescue TNBC cell growth defect by ZHX2 depletion, suggested that these downstream targets contribute to the oncogenic role of ZHX2 in an accumulative fashion. Furthermore, multiple residues (R491, R581 and R674) on ZHX2 are important in regulating its phenotype, which correspond with their roles on controlling ZHX2 transcriptional activity in TNBC cells. These studies establish that ZHX2 activates oncogenic HIF1a signaling, therefore serving as a potential therapeutic target for TNBC.
Data availability
•Sequencing data have been deposited in GEO under accession codes GSE175487
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ZHX2 promotes HIF1α oncogenic signaling in triple-negative breast cancerNCBI Gene Expression Omnibus, GSE175487.
Article and author information
Author details
Christopher Llynard Ortiz
Funding
National Cancer Institute (R01CA211732)
- Qing Zhang
National Cancer Institute (R01CA256833)
- Qing Zhang
Cancer Prevention and Research Institute of Texas (RR190058)
- Qing Zhang
American Cancer Society (RSG-18-059-01-TBE)
- Qing Zhang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal experiments were in compliance with National Institutes of Health guidelines and were approved by the University of Texas, Southwestern Medical Center Institutional Animal Care and Use Committee.
Copyright
© 2021, Fang et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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ZHX2 promotes HIF1α oncogenic signaling in triple-negative breast cancer
eLife 10:e70412.
https://doi.org/10.7554/eLife.70412
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