Prognostic value of microRNA-203a expression in breast cancer

Abstract

Tumor heterogeneity and the poor outcome of breast cancer (BC) patients have led researchers to define new markers of this disease. In recent years, microRNA expression patterns have proven to be valuable disease indicators. The level of miR-203a, in particular, was shown to be altered in different types of cancer. The objective of the present study was to assess the relationship between miR-203a expression and clinicopathological features of BC in a Portuguese cohort. The expression levels of miR‑203a were analyzed in 109 formalin‑fixed paraffin-embedded paired normal and tumor tissue samples. Significant overexpression of miR‑203a in the tumor tissues was found (1.7-fold higher) compared to the expression in the normal adjacent tissues (p=0.003). In addition, several clinicopathological characteristics presented an association with higher miR-203a expression levels. Tumors with diameter ≤18.5 mm (1.5-fold; p=0.019), tumors positive for estrogen receptor (fold-change, 1.71; p=0.042), progesterone receptor (fold-change, 1.50; p=0.046) and negative for HER2 (fold-change, 1.50; p=0.016) and high Ki-67 index (fold-change, 2.60; p=0.024) presented a significant difference in miR-203a expression compared with adjacent normal tissues. Tumors without invasion of lymph nodes also presented higher expression of miR-203a (fold-change, 2.40; p=0.004). With regard to histological classification, ductal carcinomas in situ (fold-change, 2.20; p=0.028) and invasive carcinoma NOS (fold-change, 1.71; p=0.009) displayed significantly higher expression of miR-203a. Moreover, we found a significant downregulation of miR-203a with increased stage in invasive lobular carcinomas, suggesting that miR-203a could represent a potential marker to discriminate stages in invasive lobular carcinomas.

LncRNA HOTAIR is a Prognostic Biomarker for the Proliferation and Chemoresistance of Colorectal Cancer via MiR-203a-3p-Mediated Wnt/ß-Catenin Signaling Pathway

“…The crosstalk between lncRNAs and miRNAs has been reported to control cancer progression [21]. miR-203a has been found to be a crucial regulator involved in various cancers, such as gastric cancer [22], nasopharyngeal carcinoma [23], breast cancer [24], lung cancer [25], live cancer [26], and CRC [27]. However, the potential involvement of miR-203a in the chemoresistance of CRC is not well known.…”

Upregulated miR‑203a‑3p and its potential molecular mechanism in breast cancer: A study based on bioinformatics analyses and a comprehensive meta‑analysis

“…By contrast, downregulated miR-203a-3p expression was detected in gastric cancer ( 35 ), prostate cancer ( 36 ), non-small-cell lung carcinoma ( 37 ) and esophageal cancer ( 38 ). However, only one study has identified the expression and potential functions of miR-203a-3p in BC; Gomes et al ( 21 ) reported that the expression of miR-203a-3p was markedly upregulated in 109 BC samples compared with matched normal breast samples and also identified that upregulated expression of miR-203a-3p was established in five clinic pathological characteristics groups: Tumor size ≤18.5 mm, HER2-negative, PR-positive, ER-positive and high Ki-67 index groups.…”

“…Since the sample size of the study by Gomes et al ( 21 ) was not large or varied enough, the current study combined data from three projects with a larger sample size to ensure the accuracy of the results. It was identified that the expression of precursor miR-203a was significantly elevated in 1,077 BC tissue samples compared with 104 adjacent breast tissue samples in TCGA project data.…”

“…It has been reported that miR-203a-3p can suppress hepatocellular carcinoma progression by targeting homeobox D3 through the EGFR signaling pathway ( 20 ). However, only one study has examined the role of miR-203a-3p in BC based on 109 BC cases and matched normal breast ( 21 ). Therefore, it is critical to establish the molecular mechanism of miR-203a-3p in BC with a large number of samples.…”

MiR-328 May be Considered as an Oncogene in Human Invasive Breast Carcinoma

“…Due to the lack of such studies on BC samples, we decided to perform a pilot research on those 28 BC confirmed patients who had all of our inclusion criteria (between December 2013 and April 2014). Moreover, most studies measuring miR expression level have used formalin-fixed paraffin-embedded (FFPE)-paired normal and tumor tissue samples; whereas our study was performed on fresh frozen tumor samples ( 23 - 27 ), that their RNA yield was expected to be higher ( 28 ). Clearly, obtaining and preparing fresh frozen samples are much more difficult and time- consuming.…”