MicroRNA expression profiling identifies decreased expression of miR-205 in inflammatory breast cancer

Abstract

Inflammatory breast cancer is the most aggressive form of breast cancer. Identifying new biomarkers to be used as therapeutic targets is in urgent need. Messenger RNA expression profiling studies have indicated that inflammatory breast cancer is a transcriptionally heterogeneous disease, and specific molecular targets for inflammatory breast cancer have not been well established. We performed microRNA expression profiling in inflammatory breast cancer in comparison with locally advanced noninflammatory breast cancer in this study. Although many microRNAs were differentially expressed between normal breast tissue and tumor tissue, most of them did not show differential expression between inflammatory and noninflammatory tumor samples. However, by microarray analysis, quantitative reverse transcription PCR, and in situ hybridization, we showed that microRNA-205 expression was decreased not only in tumor compared with normal breast tissue, but also in inflammatory breast cancer compared with noninflammatory breast cancer. Lower expression of microRNA-205 correlated with worse distant metastasis-free survival and overall survival in our cohort. A small-scale immunohistochemistry analysis showed coexistence of decreased microRNA-205 expression and decreased E-cadherin expression in some ductal tumors. MicroRNA-205 may serve as a therapeutic target in advanced breast cancer including inflammatory breast cancer.

The microRNA-205-5p is correlated to metastatic potential of 21T series: A breast cancer progression model

“…Indeed, miR-205-5p expression decreased with the tumor stage from Elston histological grade I through III (Fig 3), where grade III indicates tumor aggressiveness and patient poor survival [13]. Similar results were also observed in other clinical breast cancer cohorts where miR-205-5p expression levels were measured by qRT-PCR [25, 26] and by in situ hybridization [27]. In addition to the miR-205-5p downregulation in high grade tissue biopsies, the presence of blood circulating miR-205-5p, indicating an overall high expression correlated with tumor chemo sensitivity and higher rates of disease free survival [28].…”

Global Analysis of miRNA–mRNA Interaction Network in Breast Cancer with Brain Metastasis

“…A large number of genes are associated with the development and progression of breast cancer, such as the mutation of phosphatase and tensin homolog (PTEN) (6), tumor protein p53 (TP53) (5), matrix metalloproteinase 1 (MMP1) (7) and vascular endothelial growth factor (VEGF) (7). miRNAs are small (~22 nucleotides) non-coding RNAs with generegulatory functions which act by binding to the 3'untranslated region of their target mRNA, resulting in either repression of translation or mRNA degradation (8). miRNAs are remarkably tissue specific and have been used to identify the tissue in which cancer of unknown primary origin arose (9).…”

Biological subtype, treatment response and outcomes in inflammatory breast cancer using data from the National Cancer Database

“…Poor survival outcomes have prompted investigation into potential unique features of IBC that distinguish it from other types of invasive breast cancer. Some have suggested that IBC is a distinct biological subtype that transcends the standard approximated biological subtype classification based on oestrogen receptor (ER) and HER2 expression that is used to guide treatment and inform prognosis for the more common types of invasive breast cancer.…”