Integrated analysis of the potential roles of miRNA‑mRNA networks in triple negative breast cancer.

Triple negative breast cancer (TNBC) is a type of breast cancer where the tumor cells are negative for the estrogen, progesterone and human epidermal growth factor 2 receptors. To date, expression profiling of microRNA (miRNA/miR) and mRNA sequences have been widely applied for the diagnosis of TNBC. In the present study, an integrated analysis of miRNA‑mRNA profiling arrays was performed. A total of five dysregulated miRNAs in patients with TNBC were identified, including upregulated miR‑558 expression and downregulated miR‑320d‑1, miR‑548v, miR‑99a and miR‑21 expression. In addition, 49 potential target mRNA sequences were identified. Bioinformatics analyses were performed on the identified miRNAs and mRNAs, including gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes pathway and miRNA‑mRNA network analyses. A total of 31 GO terms and three signaling pathways were identified. The results indicated that the differentially expressed miRNAs and their potential target mRNAs may affect the pathogenesis of TNBC, and may therefore be considered as promising biomarkers for the early diagnosis and targeted therapy of patients with TNBC.