Analysis of miRNA-221 Expression Level in Tumors and Marginal Biopsies from Patients with Breast Cancer (Cross-Sectional Observational Study).

BACKGROUND: miRNA-221 and miRNA-222 are two homologous microRNAs, the high-expression levels of which have been commonly demonstrated in the most current human cancer types as well as breast cancer. The purpose of this research was to determine the clinical value of measuring the expression level of hsa-miR-221-3p in breast cancer tissues and evaluate its biological and prognostic importance in breast cancer (BC).

METHODS: A total of 40 tumor samples and matched tumor-free margin specimens were obtained during surgery from patients with BC. After total RNA extraction and cDNA synthesis, the relative expression level of hsa-miR221-3p in tumor and marginal tissues was examined by quantitative real-time PCR. Moreover, the association between hsa-miR-221-3p expression and clinicopathological features of patients was detected.

RESULTS: The relative expression level of hsa-miR-221-3p in BC tissues was significantly higher than that in adjacent noncancerous breast biopsies (p ≤ 0.0001). Also, there was no significant association between hsa-miR-221-3p expression with clinicopathological characteristics (p > 0.05). The receiver operating characteristic (ROC) curve analyses also represented an optimum cutoff point of < 4.34 to show that hsa-miR-221-3p is an effective molecular biomarker for BC diagnosis.

CONCLUSIONS: This study illustrated that analysis of hsa-miR-221-3p relative gene expression may be applied as a biomarker for screening BC patients and could be a substantial tool in diagnosis and prognosis. Also, that could be advantageous in decreasing surgical mistakes in tumor elimination through the surgery and enhancing all over the progression of surgery with reformed tumor clearance.