Function and mechanism of microRNAs in breast cancer

Abstract

Breast cancer is one of the most common malignant tumor in women, and its recurrence and distant metastasis are the main causes of cancer deaths. The sensitivity and specificity of current tumor markers for breast cancer cannot meet the needs of clinical practice, moreover, the assessment of the response in recurrent and metastatic breast cancer remains as major challenges. And it is also difficult to monitor the recurrence and metastasis of breast cancer. It is important to develop good markers that with high sensitivity and specificity for breast cancer in clinical practice. A widespread small single-stranded RNA molecules, microRNAs, play important roles in tumor recurrence, invasion, and metastasis. Fluctuation of a variety of miRNAs’ expression is significantly associated with progression of breast cancer, some of them are also associated with the drug resistance of tumor cells. This review summed up the relationships between the expression level of miRNAs and breast cancer, and also with the drug resistance of breast cancer cells. Meanwhile, we summarized the feasibility of treat miRNAs as tumor marker for breast cancer. Key words: Breast cancer; MicroRNA; Diagnosis; Tumor marker; Drug resistance