Analysis of miR-195 and miR-497 expression, regulation and role in breast cancer

International Conference & Exhibition on Cancer Science & Therapy

15-17 August 2011 Las Vegas, USA

Dan Li, Yulan Zhao, Changxing Liu, Xiaona Chen, Yanting Qi, Yue Jiang,, Chao Zou, Xiaolong Zhang, Shunying Liu, Xuejing Wang, Chuan-Xiu Bian, Dan Zhao, Qiang Sun, Zhenbing Zeng, Andreas Dress, Marie C. Lin, Hsiang-Fu Kung, Feng Mao, Bing- Hua Jiang, and Lihui Lai

Institute of Molecular and Chemical Biology, East China Normal University, Shanghai, China
Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
Department of General Surgery, Huashan H

Scientific Tracks Abstracts: J Cancer Sci Ther

Abstract :

Purpose: To investigate expression, regulation, potential role and targets of miR-195 and miR-497 in breast cancer. Experimental design: The expression patterns of miR-195 and miR-497 were initially examined in breast cancer tissues and cell lines by Deep sequencing: Northern blotting and quantitative real-time PCR. Combined bisulfite restriction analysis and bisulfite sequencing were carried out to study the DNA methylation status of miR-195 and miR-497 genes. Breast cancer cells stably expressing miR-195 and miR-497 were established to study their role and targets. Finally, normal, fibroadenoma and breast cancer tissues were employed to analyze the correlation between miR-195/497 levels and malignant stages of breast tumor samples. Results: MiR-195 and miR-497 were significantly down-regulated in breast cancer. The methylation state of CpG islands upstream of the miR-195/497 gene was found to be responsible for the down-regulation of both miRNAs. Forced expression of miR-195 or miR-497 suppressed breast cancer cell proliferation and invasion. Raf-1 was identified as a novel direct target of miR-195 and miR-497. miR-195/497 expression levels in clinical specimens were found to be correlated inversely with malignancy of breast cancer. Conclusion: Our data imply that both miR-195 and miR-497 play important inhibitory roles in breast cancer malignancy and may be the potential therapeutic and diagnostic targets.