1. Functional inversion of circadian regulator REV-ERBα leads to tumorigenic gene reprogramming
- Author
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Yang, Yatian, Zhang, Xiong, Cai, Demin, Zheng, Xingling, Zhao, Xuan, Zou, June X, Zhang, Jin, Borowsky, Alexander D, Dall’Era, Marc A, Corey, Eva, Mitsiades, Nicholas, Kung, Hsing-Jien, Chen, Xinbin, Li, Jian Jian, Downes, Michael, Evans, Ronald M, and Chen, Hong-Wu
- Subjects
Biochemistry and Cell Biology ,Biomedical and Clinical Sciences ,Biological Sciences ,Cancer ,Human Genome ,Genetics ,1.1 Normal biological development and functioning ,2.1 Biological and endogenous factors ,Nuclear Receptor Subfamily 1 ,Group D ,Member 1 ,Humans ,Animals ,Circadian Rhythm ,Carcinogenesis ,Mice ,Gene Expression Regulation ,Neoplastic ,Transcription Factors ,Hepatocyte Nuclear Factor 3-alpha ,Signal Transduction ,Cell Line ,Tumor ,Neoplasms ,Cell Cycle Proteins ,Nuclear Receptor Co-Repressor 1 ,Bromodomain Containing Proteins ,REV-ERB alpha ,prostate ,CRPC ,liver ,antagonist ,REV-ERBα - Abstract
Profound functional switch of key regulatory factors may play a major role in homeostasis and disease. Dysregulation of circadian rhythm (CR) is strongly implicated in cancer with mechanisms poorly understood. We report here that the function of REV-ERBα, a major CR regulator of the orphan nuclear receptor subfamily, is dramatically altered in tumors in both its genome binding and functional mode. Loss of CR is linked to a functional inversion of REV-ERBα from a repressor in control of CR and metabolic gene programs in normal tissues to a strong activator in different cancers. Through changing its association from NCoR/HDAC3 corepressor complex to BRD4/p300 coactivators, REV-ERBα directly activates thousands of genes including tumorigenic programs such as MAPK and PI3K-Akt signaling. Functioning as a master transcriptional activator, REV-ERBα partners with pioneer factor FOXA1 and directly stimulates a large number of signaling genes, including multiple growth factors, receptor tyrosine kinases, RASs, AKTs, and MAPKs. Moreover, elevated REV-ERBα reprograms FOXA1 to bind new targets through a BRD4-mediated increase in local chromatin accessibility. Pharmacological targeting with SR8278 diminishes the function of both REV-ERBα and FOXA1 and synergizes with BRD4 inhibitor in effective suppression of tumorigenic programs and tumor growth. Thus, our study revealed a functional inversion by a CR regulator in driving gene reprogramming as an unexpected paradigm of tumorigenesis mechanism and demonstrated a high effectiveness of therapeutic targeting such switch.
- Published
- 2024