Recent trends in microRNA research into breast cancer with particular focus on the associations between microRNAs and intrinsic subtypes

Abstract

MicroRNAs (miRNAs) are short non-coding RNAs that regulate the function of target genes at the post-transcriptional phase. miRNAs are considered to have roles in the development, progression and metastasis of cancer. Recent studies have indicated that particular miRNA signatures are correlated with tumor aggressiveness, response to drug therapy and patient outcome in breast cancer. On the other hand, in routine clinical practice, the treatment regimens for breast cancer are determined based on the intrinsic subtype of the primary tumor. Previous studies have shown that miRNA expression profiles of each intrinsic subtypes of breast cancer differ. In hormone receptor-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer, miRNA expressions are found to be correlated with endocrine therapy resistance, progesterone receptor expression and heat shock protein activity. Some miRNAs are associated with resistance to HER2-targeted therapy and HER3 expression in HER2-positive breast cancer. In triple-negative breast cancer, miRNA expressions are found to be associated with BRCA mutations, immune system, epithelial-mesenchymal transition, cancer stem cell properties and androgen receptor expression. As it has been clarified that the expression levels and functions of miRNA differ among the various subtypes of breast cancer, and it is necessary to take account of the characteristics of each breast cancer subtype during research into the roles of miRNA in breast cancer. In addition, the discovery of the roles played by miRNAs in breast cancer might provide new opportunities for the development of novel strategies for diagnosing and treating breast cancer.

Identification of potential new treatment response markers and therapeutic targets using a Gaussian process-based method in lapatinib insensitive breast cancer models

“…Furthermore, using Regulome explorer (http://explorer.cancerregulome.org/) we investigated whether VDR expression has any significant association with other genomic features of BC patients. It was found to have significant correlations with protein expression of Estrogen receptor and the expressions of twenty two miRNAs (Fig 4E), most of which had been previously implicated in proliferation, apoptosis, senescence, resistance to drugs including HER2 targeted therapies [71, 72]. This further strengthens VDR’s potential as therapeutic target for lapatinib insensitive BC patients.…”

Molecular Biology In Young Women With Breast Cancer: From Tumor Gene Expression To Dna Mutations

“…miRNAs and epigenetic modifications arise as potentially relevant biomarkers for risk, early diagnosis, and prognosis that can be found in liquid biopsies. The research of novel agents to regulate miRNA expression will also allow targeting miRNAs as therapeutic molecules for the treatment of BC 37 .…”

“…miRNAs are short non-coding RNA sequences that regulate gene expression by complementary binding to target mRNA transcripts, usually resulting in transcriptional repression or target degradation 37 .…”

Discovering lncRNA mediated sponge interactions in breast cancer molecular subtypes

“…Because miRNAs and mRNAs exhibit different molecular activity patterns in breast cancer subtypes [22–24], it is expected that there will be subtype-specific lncRNA-mediated sponge interactions. Identifying these miRNA sponges can both shed light on the uncharacterized mechanisms of the breast cancer subtypes and potentially help in making better therapeutic decisions.…”