Let-7 microRNA: tumour suppression activity in breast cancer


 

Abstract

Breast cancer is the leading cause of cancer death among women and characterized by deregulated expression of several tumor suppressor or oncogenic miRNAs. Mutations in these miRNAs resulted in abnormalities in cell-cycle exit as well as in the execution of a terminal differentiation program, preventing cells from reaching their fully differentiated state. The objective of this study was the identification and characterization of miR-let-7c as a potential tumor suppressor in breast cancer. Levels of expression of miR-let-7c were examined in breast cancer cell lines and tissues analysis using qRT-PCR. The results from this study show that the level of let-7c was significantly decreased in tumor compared to their matched normal breast tissues, and further, decreased in metastatic breast tumor. Furthermore, down-regulation of let-7c increased cell proliferation of breast cancer cells line. Reconstitution of Let-7c by lentiviral-mediated intratumoral delivery significantly reduced tumor burden in xenografts of breast cancer cells. Thus, profiling miRNA-Let-7 is in need to clarify intercellular signaling and discover a novel breast tumor marker and therapeutic targets.

Keywords: Breast cancer; Let-7; mRNA; Xenograft; qRT-PCR

Copyright © 2015 by The American Society for BioMedicine and BM-Publisher, Inc.

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Research Article
DOI: http://dx.doi.org/10.18081/2333-5106/015-02/389-399
American Journal of BioMedicine 2015, Volume 3, Issue 2, pages 89–99
Received November 13, 2014; Accepted March; 11, 2015, Published April 30, 2015

How to cite this article
Xerri Y, Evans MN, Inoue G, Hanley TK, Hainz DL. Let-7 microRNA: tumor suppression activity in breast cancer. American Journal of BioMedicine 2015;3(2):89–99
Review Article
1. Abstract
2. Keywords
3. Introduction
5. Results
6. Discussion
7. References

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