Loss of the multifunctional RNA-binding protein RBM47 as a source of selectable metastatic traits in breast cancer
Abstract
The mechanisms through which cancer cells lock in altered transcriptional programs in support of metastasis remain largely unknown. Through integrative analysis of clinical breast cancer gene expression datasets, cell line models of breast cancer progression, and mutation data from cancer genome resequencing studies, we identified RNA binding motif protein 47 (RBM47) as a suppressor of breast cancer progression and metastasis. RBM47 inhibited breast cancer re-initiation and growth in experimental models. Transcriptome-wide HITS-CLIP analysis revealed widespread RBM47 binding to mRNAs, most prominently in introns and 3'UTRs. RBM47 altered splicing and abundance of a subset of its target mRNAs. Some of the mRNAs stabilized by RBM47, as exemplified by dickkopf WNT signaling pathway inhibitor 1, inhibit tumor progression downstream of RBM47. Our work identifies RBM47 as an RNA-binding protein that can suppress breast cancer progression and demonstrates how the inactivation of a broadly targeted RNA chaperone enables selection of a pro-metastatic state.
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Author details
Reviewing Editor
- Roy Parker, University of Colorado, United States
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#99-09-032) of Memorial Sloan Kettering Cancer Center. All surgery was performed under sodium pentobarbital anesthesia, and every effort was made to minimize suffering.
Version history
- Received: March 7, 2014
- Accepted: May 31, 2014
- Accepted Manuscript published: June 4, 2014 (version 1)
- Version of Record published: July 1, 2014 (version 2)
Copyright
© 2014, Vanharanta 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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