the role of oncomirs in the pathogenesis of breast cancer: a review

intoduction: the discovery of micrornas (mirnas), an extensive family of small non-protein-coding rnas, provided an exciting era in cancer research and recent findings have prompted us to revise the traditional concept of cancer. deregulated mirnas   expression influences biological events leading to cancer such as proliferation, differentiation, metastasis and apoptosis. the expression of oncogenic mirnas (oncomirs) is markedly upregulated in various types of malignancy. increased level of oncomirs suppresses the expression of tumor-suppressor genes which involved in cell proliferation, dna repair, apoptosis and metastasis. here, we reviewed the current literatures to elucidate mechanisms by which upregulated oncomirs expression contribute in pathogenesis of breast cancer. better understanding of these mechanisms will surely open new avenues for early detection of breast cancer, as well as for the development of novel prevention and treatment strategies.