miR-205 and miR-200c: Predictive Micro RNAs for Lymph Node Metastasis in Triple Negative Breast Cancer

PURPOSE: We examined expression profiles of 16 micro RNAs (miRNAs) in triple negative breast cancers to identify their potential as biomarkers for lymph node metastasis. METHODS: The expression profiles of miR-9, miR-21, miR-30a, miR-30d, miR-31, miR-34a, miR-34c, miR-100, miR-122, miR-125b, miR-146a, miR-146b, miR-155, miR-181a, miR-200c, and miR-205 were examined by using real-time quantitative reverse transcription polymerase chain reaction in tumor samples and corresponding benign breast tissues. Their associations with histopathological features and prognostic parameters were assessed. RESULTS: When compared with the expression in benign breast tissues, seven of the miRNAs (miR-31, miR-205, miR-34a, miR-146a, miR-125b, miR-34c, and miR-181a) were downregulated more than 1.5-fold in tumor tissues, whereas, only miR-21 was found to be upregulated more than 1.5-fold in tumor tissues. Although miR-200c levels were decreased only 1.12-fold in tumor tissues, the reduced expressions of miR-200c and miR-205 were significantly associated with lymph node metastasis (p=0.021 and p=0.016, respectively). CONCLUSION: Our results demonstrate that miR-205 and miR-200c expression levels may be useful in predicting lymph node metastasis in triple negative breast cancer patients.