FXR1 regulates transcription and is required for growth of human cancer cells with TP53/FXR2 homozygous deletion
- Novartis Institute for BioMedical Research, China
- Novartis Institutes for BioMedical Research, China
- Tongji University, China
Abstract
Tumor suppressor p53 prevents cell transformation by inducing apoptosis and other responses. Homozygous TP53 deletion occurs in various types of human cancers for which no therapeutic strategies have yet been reported. Based on TCGA database analysis, TP53 homozygous deletion locus mostly exhibits co-deletion of the neighboring gene FXR2, which belongs to the Fragile X gene family. Here, we demonstrate that inhibition of the remaining family member FXR1 selectively blocks cell proliferation in cancer cells containing homozygous deletion of both TP53 and FXR2 in a collateral lethality manner. Mechanistically, in addition to its RNA-binding function, FXR1 recruits transcription factor STAT1 or STAT3 to gene promoters at the chromatin interface and regulates transcription thus, at least partially, mediating cell proliferation. Our study anticipates that inhibition of FXR1 is a potential therapeutic approach to targeting human cancers harboring TP53 homozygous deletion.
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Funding
Novartis (Research)
- Bin Xiang
Novartis (Postdoc program)
- Yichao Fan
The authors declare that there was no funding for this work.
Ethics
Animal experimentation: All the procedures related to animal handling, care and the treatment in the study were performed according to the guidelines approved by the Institutional Animal Care and Use Committee (IACUC) of WuXi AppTec following the guidance of the Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC). The approved protocol number is R20150728-Mouse and Rat. The animals were daily checked for any effects of tumor growth and treatments on normal behavior such as mobility, food and water consumption, body weight gain/loss, eye/hair matting and any other abnormal effects. Death and observed clinical signs were recorded.
Copyright
© 2017, Fan 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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FXR1 regulates transcription and is required for growth of human cancer cells with TP53/FXR2 homozygous deletion
eLife 6:e26129.
https://doi.org/10.7554/eLife.26129
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