Role of MicroRNA-31 (miR-31) in Breast Carcinoma Diagnosis and Prognosis.

BACKGROUND/AIM:Breast cancer (BC) is among the most widespread malignant tumors in women. In the current study, we evaluated the role of miR-31 in BC patients and its relation to the different prognostic, clinical, and pathological features. PATIENTS AND METHODS:MiR-31 levels were determined by RT-PCR in BC and adjacent normal breast tissues from 100 BC patients. BC diagnosis was established through histopathological examinations. The expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) receptor in all tumors was determined using immunohistochemistry. RESULTS:MiR-31 expression was reduced in BC tissues relative to adjacent healthy breast tissue (mean levels were 0.93 and 7.2, respectively). Also, the low expression of miR-31 in BC patients was significantly correlated with adverse clinical and pathological features such as: young patient's age, premenopausal status, infiltrative lobular carcinoma, ER and PR negative tumors, HER2 positive tumors, and advanced clinical stage. CONCLUSION:MiR-31 was expressed at low levels in BC tissues and correlated with adverse clinical and pathological features, and poor survival.