The role of microRNA-449 in Human Breast Cancer

Ajay Shah


In 2010, an estimated 173 800 cases of cancer were diagnosed in Canada and 76 200 of these cases were expected to be fatal. Current treatment options are often very invasive, harmful, and ineffective. The purpose of this experiment was to mitigate tumour growth by manipulation of micro-RNA (mRNA) levels. mRNAs are small proteins, and levels of specific mRNAs are deregulated in cancer cells. In this experiment, levels of micro-RNA 449, which is deregulated in breast cancer cell lines, were returned to their baseline levels. Numerous tests were then conducted to test the viability of the resulting cells. Replicable experiments showed that the strength, motility and invasiveness of the breast cancer cells was greatly diminished after mRNA-449 levels returned to baseline levels. Furthermore, research indicated that 4 potential genes (CRIP2, XBP1, TAF4B, and SFXN2) can be manipulated in future experiments to further diminish the viability of the breast cancer tumours. 

En 2015, 25220 cas estimés de cancer du sein ont été diagnostiqués au Canada et 5060 de ces cas étaient prévus d’être fatales. Les options de traitement courantes sont souvent très envahissantes, nuisibles et inefficaces. L’objet de cette expérience était d’atténuer la croissance de la tumeur en manipulant les niveaux d’ARN-Micro. ARNm sont de petites molécules qui codent pour des protéines et en cellules de cancer, les niveaux de certains ARNms sont dérégulés. Les niveaux d’ARN-micro 449, qui sont dérégulés dans les lignées cellulaires de cancer du sein, ont été retournées à leurs niveaux de base dans cette expérience. La viabilité des cellules ainsi obtenues a été analysé par plusieurs tests. Les expériences reproductibles ont indiqué que la force, la mobilité et le caractère invasif des cellules de cancer du sein ont été diminués après que les niveaux d’ARN-micro 449 sont retournés à leurs niveaux de base. En outre, l’étude a révélé que quatre gènes potentiels (CRIP2, XBP1, TAF4B, et SFXN2) pourraient être manipulés à l’avenir pour réduire davantage la viabilité des tumeurs du cancer du sein.


microRNA-449; deregulation; breast cancer; anti-miR; microRNA knockdown

Full Text:



Canada, Canadian Cancer Society, Public Health Agency of Canada. (2011, May). Canadian Cancer Statistics 2011. Retrieved October 8, 2012, from

Carlson, R. W., Allred D. C., Anderson, B. O., Harold J. Burstein, W. Bradford Carter, Stephen B. Edge, John K. Erban, William B. Farrar, Lori J. Goldstein, William J. Gradishar, Daniel F. Hayes, Clifford A. Hudis, Mohammad Jahanzeb, Krystyna Kiel, Britt-Marie Ljung, P. Kelly Marcom, Ingrid A. Mayer, Beryl McCormick, Lisle M. Nabell, Lori J. Pierce, Elizabeth C. Reed, Mary Lou Smith, George Somlo, Richard L. Theriault, Neal S. Topham, John H. Ward, Eric P. Winer & Antonio C. Wolff (2009). Breast Cancer. Clinical Practice Guidelines in Oncology, 7(2), 122-192. Retrieved from

Grigoriadis, A., Mackay, A., Reis-Filho, J. S., Steele, D., Iseli, C., Stevenson, B. J., ... O'Hare, M. J. (2006). Establishment of the epithelial-specific transcriptome of normal and malignant human breast cells based on MPSS and array expression data. Breast Cancer Research, 8(5), r56. doi: 10.1186/bcr1604

Hashimoto, Y., Akiyama, Y., Otsubo, T., Shimada, S., & Yuasa, Y. (2010). Involvement of epigenetically silenced microRNA-181c in gastric carcinogenesis. Carcinogenesis, 31(5), 777-784. doi: 10.1093/carcin/bgq013

Liu, C., & Tang, D. G. (2011). MicroRNA Regulation of Cancer Stem Cells. Cancer Research, 71(18), 5950-5954. doi: 10.1158/0008-5472.CAN-11-1035

Mutalib, N. A., Learn-Han, L., Sidik, S. M., Rahman, S. A., Singh, A. S., & Yoke-Kqueen, C. (2012). miR-181a regulates multiple pathways in hypopharyngeal squamous cell carcinoma. African Journal of Biotechnology, 11(22), 6129-6137. Retrieved April 13, 2012, from

Nunez, R. (2001). DNA measurement and cell cycle analysis by flow cytometry. Current Issues in Molecular Biology, 3(3), 67-70.

Wang, Y., Yu, Y., Tsuyada, A., Ren, X., Wu, X., & Stubblefield, K. (2011). Transforming growth factor-β regulates the sphere-initiating stem cell-like feature in breast cancer through miRNA-181 and ATM. Oncogene 30, 1470-1480. Retrieved April 14, 2012, from



  • There are currently no refbacks.

Copyright (c) 2016 Journal of Student Science and Technology