Inflammatory breast carcinoma: Elevated microrna MiR‐181b‐5p and reduced MiR‐200b‐3p, MiR‐200c‐3p, and MiR‐203a‐3p expression as potential biomarkers with diagnostic value

Abstract

Inflammatory breast cancer (IBC) is a rare yet aggressive breast cancer variant, associated with a poor prognosis. The major challenge for IBC is misdiagnosis due to the lack of molecular biomarkers. We profiled dysregulated expression of microRNAs (miRNAs) in primary samples of IBC and non‐IBC tumors using human breast cancer miRNA PCR array. We discovered that 28 miRNAs were dysregulated (10 were upregulated, while 18 were underexpressed) in IBC vs. non‐IBC tumors. We identified 128 hub genes, which are putative targets of the differentially expressed miRNAs and modulate important cancer biological processes. Furthermore, our qPCR analysis independently verified a significantly upregulated expression of miR‐181b‐5p, whereas a significant downregulation of miR‐200b‐3p, miR‐200c‐3p, and miR‐203a‐3p was detected in IBC tumors. Receiver operating characteristic (ROC) curves implied that the four miRNAs individually had a diagnostic accuracy in discriminating patients with IBC from non‐IBC and that miR‐203a‐3p had the highest diagnostic value with an AUC of 0.821. Interestingly, a combination of miR‐181b‐5p, miR‐200b‐3p, and miR‐200c‐3p robustly improved the diagnostic accuracy, with an area under the curve (AUC) of 0.897. Intriguingly, qPCR revealed that the expression of zinc finger E box‐binding homeobox 2 (ZEB2) mRNA, the putative target of miR‐200b‐3p, miR‐200c‐3p, and miR‐203a‐3p, was upregulated in IBC tumors. Overall, this study identified a set of miRNAs serving as potential biomarkers with diagnostic relevance for IBC.