No conflicts of interest were declared.
Biological and prognostic associations of miR-205 and let-7b in breast cancer revealed by in situ hybridization analysis of micro-RNA expression in arrays of archival tumour tissue†
Article first published online: 8 MAY 2012
Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The Journal of Pathology
Volume 227, Issue 3, pages 306–314, July 2012
How to Cite
Quesne, J. L., Jones, J., Warren, J., Dawson, S.-J., Ali, H. R., Bardwell, H., Blows, F., Pharoah, P. and Caldas, C. (2012), Biological and prognostic associations of miR-205 and let-7b in breast cancer revealed by in situ hybridization analysis of micro-RNA expression in arrays of archival tumour tissue. J. Pathol., 227: 306–314. doi: 10.1002/path.3983
- Issue published online: 6 JUN 2012
- Article first published online: 8 MAY 2012
- Accepted manuscript online: 4 JAN 2012 07:34AM EST
- Manuscript Accepted: 20 DEC 2011
- Manuscript Revised: 19 DEC 2011
- Manuscript Received: 14 JUL 2011
- breast cancer;
- in situ hybridization;
Micro-RNAs (miRNAs) are frequently dysregulated in a range of human malignancies, many have been shown to act either as tumour supressors or oncogenes and several have been implicated in breast cancer. However, breast cancer is a diverse disease and little is known about the relationships between miRNA expression, clinical outcome and tumour subtype. We used locked nucleic acid probe in situ hybridization (LNA-ISH) to visualize, in tissue micro-arrays (TMAs) of 2919 formalin-fixed paraffin-embedded (FFPE) archival breast tumours, the expression of two key miRNAs that are frequently lost in a range of solid malignancies, let-7b and miR-205. These miRNAs were also quantified by quantitative reverse transcription PCR in cores of FFPE tissue from 40 of these cases, demonstrating that LNA-ISH is semi-quantitative. The tumours in the TMAs were assigned to subtypes based on their immunohistochemical (IHC) staining with ER, PR, HER2, CK5/6 and EGFR. let-7b expression was shown to be associated with luminal tumours and to have an independent significant positive prognostic value in this group. miR-205 is associated with tumours of ductal morphology and is of significant positive prognostic value within these tumours. We propose that the expression of miR-205 may contribute to ductal tumour morphology. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.