Epigenetic inactivation of microRNA gene hsa‐mir‐9‐1 in human breast cancer

• DOI: 10.1002/path.2251
• Publication Date: 2007-10-18T13:46:22Z
• Authors: U Lehmann; B Hasemeier; M Christgen; M Müller; D Römermann; F Länger; H Kreipe
• Keywords: Demethylating agent

Abstract MicroRNAs (miRNAs) represent a new class of small non‐coding RNAs regulating gene expression by inducing RNA degradation or interfering with translation. Aberrant miRNA has been described for several human malignancies and tumour suppressor functions have ascribed to this regulatory RNAs. Accordingly, inactivation due deletion mutation found in malignancies. Here, we describe the role aberrant hypermethylation as an additional mechanism breast cancer. was shown mir‐9‐1, mir‐124a3, mir‐148, mir‐152 , mir‐663 34–86% cases series 71 primary cancer specimens. For comprehensive methylation analysis, combined bisulphite restriction sequencing, Pyrosequencing ™ were employed. correlated strongly known genes ( p = 0.003). After treatment various cell lines demethylating agent 5‐aza‐2′‐deoxycytidine, reduction mir‐9‐1 concomitant reactivation could be observed. gene, which is already hypermethylated pre‐invasive intraductal lesions, good correlation between quantitative level demonstrated subset specimen r 0.8). In conclusion, study demonstrates that microRNA are also affected epigenetic early frequent event development. Copyright © 2007 Pathological Society Great Britain Ireland. Published John Wiley & Sons, Ltd.