Study of mir-494 expression and its association with tumor histopathological characteristics to find a possible breast cancer biomarker

Seyedeh elham Sharifi ardani,1,* Mahdieh salimi ,2 Pegah ghoraeian,3

1. Islamic Azad University of Tehran Medical Branch
2. Department of Medical Genetics, Institute of Medical Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB)
3. Islamic Azad University of Tehran Medical Branch



Breast cancer is a major health problem that affects one in eight women worldwide and is the second most common malignancy diagnosed in women, there are numerous risk factors for breast cancer, including age, obesity, family history, and exposure to hormones and therapeutic radiation. effective management of breast cancer depends on early diagnosis and proper monitoring of patients’ response to therapy. however, these goals are difficult to achieve because of the lack of sensitive and specific biomarkers for early detection and disease monitoring. the micrornas (mirnas or mirs), a type of small non-coding rna , have emerged as molecular regulators that can have key roles as tumor suppressors or oncogenes in pathogenesis and progression of different malignancies, including breast cancer.


Breast cancer tumor specimens and their matched non-cancerous tissues were obtained from 30 patients diagnosed with breast cancer. in the present study total rna of breast cancer tissues was extracted with trizol solution referring to manufacture’s protocols. equal amount of total rna was then transcribed into the first-strand cdna using bonmir kit. the expression of mir-494 in 30 tumoral and 30 normal breast tissues were analyzed using sybr green real-time pcr technique. the statistical significance of data was evaluated by spss version 16 software.


The data revealed that the expression of mir-494 was up-regulated in breast cancer tumors compared with normal breast tissues thus identified as onco- mirna in human breast cancer. also the positive association was observed between mir-494 expression and metastasis. additionally, retinoblastoma 1 (rb1) was identified to be a downstream target of mir-494 by in silico analysis.


This study may provide useful information for further investigations of functional roles of mirnas in breast cancer development, progression, diagnosis, and prognosis


micrornas, biomarkers, breast cancer