ATM regulation of IL-8 links oxidative stress to cancer cell migration and invasion
Abstract
Ataxia-telangiectasia mutated (ATM) protein kinase regulates the DNA damage response (DDR) and is associated with cancer suppression. Here we report a cancer-promoting role for ATM. ATM depletion in metastatic cancer cells reduced cell migration and invasion. Transcription analyses identified a gene network, including the chemokine IL-8, regulated by ATM. IL-8 expression required ATM and was regulated by oxidative stress. IL-8 was validated as an ATM target by its ability to rescue cell migration and invasion defects in ATM-depleted cells. Finally, ATM-depletion in human breast cancer cells reduced lung tumors in a mouse xenograft model and clinical data validated IL-8 in lung metastasis. These findings provide insights into how ATM activation by oxidative stress regulates IL-8 to sustain cell migration and invasion in cancer cells to promote metastatic potential. Thus, in addition to well-established roles in tumor suppression, these findings identify a role for ATM in tumor progression.
Article and author information
Author details
Reviewing Editor
- Joaquin M Espinosa, University of Colorado Boulder, United States
Ethics
Animal experimentation: Experiments involving Balb/c mice for this study were performed in strict accordance with guidelines set forth for the handling and care of animals by the institutional animal care and use committee (IACUC) protocols (AUP-2012-00075) of the University of Texas at Austin.
Version history
- Received: February 28, 2015
- Accepted: May 31, 2015
- Accepted Manuscript published: June 1, 2015 (version 1)
- Version of Record published: June 12, 2015 (version 2)
Copyright
© 2015, Chen 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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