A regulatory circuit of miR-148a/152 and DNMT1 in modulating cell transformation and tumor angiogenesis through IGF-IR and IRS1

The Role of MicroRNAs in Influencing Body Growth and Development

Body growth and development are regulated among others by genetic and epigenetic factors. MicroRNAs (miRNAs) are epigenetic regulators of gene expression that act at the post-transcriptional level, thereby exerting a strong influence on regulatory gene networks. Increasing studies suggest the importance of miRNAs in the regulation of the growth plate and growth hormone (GH)-insulin-like growth factor (IGF) axis during the life course in a broad spectrum of animal species, contributing to longitudinal growth. This review summarizes the role of miRNAs in regulating growth in different in vitro and in vivo models acting on GH, GH receptor (GHR), IGFs, and IGF1R genes besides current knowledge in humans, and highlights that this regulatory system is of importance for growth.

Human Milk Exosomal MicroRNA: Associations with Maternal Overweight/Obesity and Infant Body Composition at 1 Month of Life

Among all the body fluids, breast milk is one of the richest sources of microRNAs (miRNAs). MiRNAs packaged within the milk exosomes are bioavailable to breastfeeding infants. The role of miRNAs in determining infant growth and the impact of maternal overweight/obesity on human milk (HM) miRNAs is poorly understood. The objectives of this study were to examine the impact of maternal overweight/obesity on select miRNAs (miR-148a, miR-30b, miR-29a, miR-29b, miR-let-7a and miR-32) involved in adipogenesis and glucose metabolism and to examine the relationship of these miRNAs with measures of infant body composition in the first 6 months of life. Milk samples were collected from a cohort of 60 mothers (30 normal-weight [NW] and 30 overweight [OW]/obese [OB]) at 1-month and a subset of 48 of these at 3 months of lactation. Relative abundance of miRNA was determined using real-time PCR. The associations between the miRNAs of interest and infant weight and body composition at one, three, and six months were examined after adjusting for infant gestational age, birth weight, and sex. The abundance of miR-148a and miR-30b was lower by 30% and 42%, respectively, in the OW/OB group than in the NW group at 1 month. miR-148a was negatively associated with infant weight, fat mass, and fat free mass, while miR-30b was positively associated with infant weight, percent body fat, and fat mass at 1 month. Maternal obesity is negatively associated with the content of select miRNAs in human milk. An association of specific miRNAs with infant body composition was observed during the first month of life, suggesting a potential role in the infant's adaptation to enteral nutrition.

Breast Cancer and the Other Non-Coding RNAs

Breast cancer is very heterogenous and the most common gynaecological cancer, with various factors affecting its development. While its impact on human lives and national health budgets is still rising in almost all global areas, many molecular mechanisms affecting its onset and development remain unclear. Conventional treatments still prove inadequate in some aspects, and appropriate molecular therapeutic targets are required for improved outcomes. Recent scientific interest has therefore focused on the non-coding RNAs roles in tumour development and their potential as therapeutic targets. These RNAs comprise the majority of the human transcript and their broad action mechanisms range from gene silencing to chromatin remodelling. Many non-coding RNAs also have altered expression in breast cancer cell lines and tissues, and this is often connected with increased proliferation, a degraded extracellular environment, and higher endothelial to mesenchymal transition. Herein, we summarise the known abnormalities in the function and expression of long non-coding RNAs, Piwi interacting RNAs, small nucleolar RNAs and small nuclear RNAs in breast cancer, and how these abnormalities affect the development of this deadly disease. Finally, the use of RNA interference to suppress breast cancer growth is summarised.

Epidrug Modulated Expression of MiR--152 and MiR-148a Reverse Cisplatin Resistance in Ovarian Cancer Cells: An Experimental In-vitro Study

Cisplatin is a common agent which is used to treat Epithelial Ovarian Cancer (EOC), but cisplatin resistance is a major obstacle in successful treatment of ovarian cancer. Aberration in epigenetic changes play an important role in disregulation of gene expression. MiR-152 and miR-148a are frequently down-regulated in EOC due to promoter hyper-methylation. DNA methyltransferase1 (DNMT1), the main enzyme in maintenance of the pattern of DNA methylation, is one of the targets of miR-152 and miR-148a. Aberrantly up-regulation of DNMT1 is responsible for silencing of tumor suppressor genes in carcinogenesis. We hypothesized that re-expression of miR-152 and miR-148a and consequently down-regulation of DNMT1 may resensitize cancerous cells to chemotherapeutics agents. The aim of the present study is to investigate the effect of 5-azacytidine (5-Aza) and Trichostatin A on miR-152 and miR-148a expression in A2780CP ovarian cancer cell line. Optimal doses of 5-Azacitidine and TSA were measured by 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. A2780CP cell line was treated by each drugs, alone or in combination and the expression of miR-148a, miR-152 and DNMT1 was evaluated by Real-Time Quantitative Reverse Transcription-Polymerase Chain Reaction (RT-qPCR). The results revealed that TSA and 5-Azacytidine are able to revive the expression of miR-148a and miR-152 genes and mediate growth inhibition of epithelial ovarian cancer cells. The present study suggests that re-expression of miR-148a and miR-152 by epigenetic therapy aiming to DNMT1 suppression might resensitize resistant ovarian tumors to conventional chemotherapy.

Regulation of Toll-like receptor-mediated inflammatory response by microRNA-152-3p-mediated demethylation of MyD88 in systemic lupus erythematosus

OBJECTIVE

microRNAs (miRNAs) play critical roles in embryogenesis, cell differentiation and the pathogenesis of several human diseases, including systemic lupus erythematosus (SLE). Toll-like receptors (TLRs) are also known to exert crucial functions in the immune response activation occurring in the pathogenesis of autoimmune diseases like SLE. Herein, the current study aimed to explore the potential role of miR-152-3p in TLR-mediated inflammatory response in SLE.

METHODS

We determined the miR-152-3p expression profiles in CD4+ T cells and peripheral blood mononuclear cells (PBMCs) harvested from patients with SLE and healthy controls, and analyzed the correlation between miR-152-3p expression and clinicopathological parameters. CD70 and CD40L expression patterns in CD4+ T cells were assessed by RT-qPCR and flow cytometry. ChIP was adopted to determine the enrichment of DNA methyltransferase 1 (DNMT1) in the promoter region of myeloid differentiation factor 88 (MyD88).

RESULTS

The obtained findings revealed that miR-152-3p was highly-expressed in CD4+ T cells and PBMCs of patients with SLE, and this high expression was associated with facial erythema, joint pain, double-stranded DNA, and IgG antibody. DNMT1 could be enriched in the MyD88 promoter, and miR-152-3p inhibited the methylation of MyD88 by targeting DNMT1. We also found that silencing miR-152-3p inhibited MyD88 expression not only to repress the autoreactivity of CD4+ T cells and but also to restrain their cellular inflammation, which were also validated in vivo.

CONCLUSION

Our study suggests that miR-152-3p promotes TLR-mediated inflammatory response in CD4+ T cells by regulating the DNMT1/MyD88 signaling pathway, which highlights novel anti-inflammatory target for SLE treatment.

miRNAs: Critical mediators of breast cancer metastatic programming

MicroRNA mediated aberrant gene regulation has been implicated in several diseases including cancer. Recent research has highlighted the role of epigenetic modulation of the complex process of breast cancer metastasis by miRNAs. miRNAs play a crucial role in the process of metastatic evolution by facilitating alterations in the phenotype of tumor cells and the tumor microenvironment that promote this process. They act as critical determinants of the multi-step progression starting from carcinogenesis all the way to organotropism. In this review, we focus on the current understanding of the compelling role of miRNAs in breast cancer metastasis.

MicroRNA-1323 downregulation promotes migration and invasion of breast cancer cells by targeting tumour protein D52

Breast cancer (BC) is one of the most common malignancies globally in women, with high mortality rate as a result of tumour metastasis. MicroRNAs play vital roles in the occurrence and development of human cancer. This study aimed to investigate the biological roles of miR-1323 in BC. The expression levels of miR-1323 were detected by quantitative real-time PCR assay. The effect of miR-1323 on BC cell proliferation was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and colony formation assay. Wound healing analysis and Matrigel Transwell assay were conducted to evaluate miR-1323-mediated BC cell migration and invasion. A luciferase reporter assay was used to test the target of miR-1323. We found that miR-1323 levels were downregulated in BC tissues and serums. Low-miR-1323 levels were associated with lymph node metastasis and advanced clinical stage. Tumour protein D52 (TPD52) was identified as a direct target of miR-1323. Low expression of miR-1323 contributed to the overexpression of TPD52 leading to enhanced BC progression. Our findings suggest that silencing of miR-1323 enhances BC development by regulating TPD52 expression, suggesting that miR-1323 and TPD52 may serve as potential therapeutic targets for BC treatment.

miR-210 and miR-152 as Biomarkers by Liquid Biopsy in Invasive Ductal Carcinoma

Detecting circulating microRNAs (miRNAs; miRs) by means of liquid biopsy is an important tool for the early diagnosis and prognosis of breast cancer (BC). We aimed to identify and validate miR-210 and miR-152 as non-invasive circulating biomarkers, for the diagnosis and staging of BC patients, confirming their involvement in tumor angiogenesis. Methods: RT-qPCR was performed and MiRNA expression analysis was obtained from plasma and fragments of BC and benign breast condition (BBC) women patients, plus healthy subjects. Additionally, the immunohistochemistry technique was carried out to analyze the expression of target proteins. Results: Tumor fragments showed increased expression of oncomiR-210 and decreased expression of miR-152 tumoral suppressor. Both miRNAs were increased in plasma samples from BC patients. The receiver operating characteristic (ROC) curve analysis revealed that only the expression of oncomiR-210 in tissue samples and only the expression of the miR-152 suppressor in plasma have the appropriate sensitivity and specificity for use as differential biomarkers between early/intermediate and advanced stages of BC patients. In addition, there was an increase in the expression of hypoxia-inducible factor 1-alpha (HIF-1α), insulin-like growth factor 1 receptor (IGF-1R), and vascular endothelial growth factor (VEGF) in BC patients. On the contrary, a decrease in Von Hippel–Lindau (VHL) protein expression was observed. Conclusions: This study showed that increased levels of miR-210 and decreased levels of miR152, in addition to the expressions of their target proteins, could indicate, respectively, the oncogenic and tumor suppressive role of these miRNAs in fragments. Both miRNAs are potential diagnostic biomarkers for BC by liquid biopsy. In addition, miR-152 proved to be a promising biomarker for disease staging.

Inhibition of miR-152 during In Vitro Maturation Enhances the Developmental Potential of Porcine Embryos

Simple Summary

MiR-152 is a highly conserved miRNA across different species and plays a role in the regulation of cell differentiation, proliferation, and survival. However, the exact role of miR-152 in oocyte and embryo development is not yet known. In this study, we specifically manipulated the expression level of miR-152 in porcine cumulus-oocyte complexes (COCs) and monitored their developmental competence until the blastocyst stage. We mainly found that a suppressed expression of miR-152 during oocyte maturation significantly improved the blastocyst rate. Our results indicate that this negative correlation between miR-152 during oocyte maturation and the blastocyst rate in pigs could be through targeting IGF system components during oocyte development. These results provide more insights into the role of miRNAs during oocyte and embryonic development that could improve the in vitro production system for mammalian embryos.

Abstract

Oocyte developmental competence is regulated by various mechanisms and molecules including microRNAs (miRNAs). However, the functions of many of these miRNAs in oocyte and embryo development are still unclear. In this study, we managed to manipulate the expression level of miR-152 during oocyte maturation to figure out its potential role in determining the developmental competence of porcine oocytes. The inhibition (Inh) of miR-152 during oocyte maturation does not affect the MII and cleavage rates, however it significantly enhances the blastocyst rate compared to the overexpression (OvExp) and control groups. Pathway analysis identified several signaling pathways (including PI3K/AKT, TGFβ, Hippo, FoxO, and Wnt signaling) that are enriched in the predicted target genes of miR-152. Gene expression analysis revealed that IGF1 was significantly up-regulated in the Inh group and downregulated in the OvExp group of oocytes. Moreover, IGF1R was significantly upregulated in the Inh oocyte group compared to the control one and IGFBP6 was downregulated in the Inh oocyte group compared to the other groups. Blastocysts developed from the OvExp oocytes exhibited an increase in miR-152 expression, dysregulation in some quality-related genes, and the lowest rate of blastocyst formation. In conclusion, our results demonstrate a negative correlation between miR-152 expression level and blastocyst rate in pigs. This correlation could be through targeting IGF system components during oocyte development.

Integrative p53, micro-RNA and Cathepsin Protease Co-Regulatory Expression Networks in Cancer

Simple Summary

This article describes an emerging area of significant interest in cancer and cell death and the relationships shared by these through the transcriptional regulation of cathepsin protease genes by micro-RNAs that are connected to p53 activation. While it has been demonstrated that the p53 protein can directly regulate some cathepsin genes and the expression of their upstream regulatory micro-RNAs, very little is known about what input the p53 isoform proteins may have in regulating this relationship. Herein, we draw attention to this important regulatory aspect in the context of describing mechanisms that are being established for the micro-RNA regulation of cathepsin protease genes and their collective use in diagnostic or prognostic assays.

Abstract

As the direct regulatory role of p53 and some of its isoform proteins are becoming established in modulating gene expression in cancer research, another aspect of this mode of gene regulation that has captured significant interest over the years is the mechanistic interplay between p53 and micro-RNA transcriptional regulation. The input of this into modulating gene expression for some of the cathepsin family members has been viewed as carrying noticeable importance based on their biological effects during normal cellular homeostasis and cancer progression. While this area is still in its infancy in relation to general cathepsin gene regulation, we review the current p53-regulated micro-RNAs that are generating significant interest through their regulation of cathepsin proteases, thereby strengthening the link between activated p53 forms and cathepsin gene regulation. Additionally, we extend our understanding of this developing relationship to how such micro-RNAs are being utilized as diagnostic or prognostic tools and highlight their future uses in conjunction with cathepsin gene expression as potential biomarkers within a clinical setting.

Regulatory Mechanisms of Epigenetic miRNA Relationships in Human Cancer and Potential as Therapeutic Targets

Simple Summary

By the virtue of targeting multiple genes, a microRNA (miRNA) can infer variable consequences on tumorigenesis by appearing as both a tumour suppressor and oncogene. miRNAs can regulate gene expression by modulating genome-wide epigenetic status of genes that are involved in various cancers. These miRNAs perform direct inhibition of key mediators of the epigenetic machinery, such as DNA methyltransferases (DNMTs) and histone deacetylases (HDACs) genes. Along with miRNAs gene expression, similar to other protein-coding genes, miRNAs are also controlled by epigenetic mechanisms. Overall, this reciprocal interaction between the miRNAs and the epigenetic architecture is significantly implicated in the aberrant expression of miRNAs detected in various human cancers. Comprehensive knowledge of the miRNA-epigenetic dynamics in cancer is essential for the discovery of novel anticancer therapeutics.

Abstract

Initiation and progression of cancer are under both genetic and epigenetic regulation. Epigenetic modifications including alterations in DNA methylation, RNA and histone modifications can lead to microRNA (miRNA) gene dysregulation and malignant cellular transformation and are hereditary and reversible. miRNAs are small non-coding RNAs which regulate the expression of specific target genes through degradation or inhibition of translation of the target mRNA. miRNAs can target epigenetic modifier enzymes involved in epigenetic modulation, establishing a trilateral regulatory “epi–miR–epi” feedback circuit. The intricate association between miRNAs and the epigenetic architecture is an important feature through which to monitor gene expression profiles in cancer. This review summarises the involvement of epigenetically regulated miRNAs and miRNA-mediated epigenetic modulations in various cancers. In addition, the application of bioinformatics tools to study these networks and the use of therapeutic miRNAs for the treatment of cancer are also reviewed. A comprehensive interpretation of these mechanisms and the interwoven bond between miRNAs and epigenetics is crucial for understanding how the human epigenome is maintained, how aberrant miRNA expression can contribute to tumorigenesis and how knowledge of these factors can be translated into diagnostic and therapeutic tool development.

Circulating miRNAs in HER2-Positive and Triple Negative Breast Cancers: Potential Biomarkers and Therapeutic Targets

Breast cancer is one of the most prevalent diseases among women worldwide and is highly associated with cancer-related mortality. Of the four major molecular subtypes, HER2-positive and triple-negative breast cancer (TNBC) comprise more than 30% of all breast cancers. While the HER2-positive subtype lacks estrogen and progesterone receptors and overexpresses HER2, the TNBC subtype lacks estrogen, progesterone and HER2 receptors. Although advances in molecular biology and genetics have substantially ameliorated breast cancer disease management, targeted therapies for the treatment of estrogen-receptor negative breast cancer patients are still restricted, particularly for TNBC. On the other hand, it has been demonstrated that microRNAs, miRNAs or small non-coding RNAs that regulate gene expression are involved in diverse biological processes, including carcinogenesis. Moreover, circulating miRNAs in serum/plasma are among the most promising diagnostic/therapeutic tools as they are stable and relatively easy to quantify. Various circulating miRNAs have been identified in several human cancers including specific breast cancer subtypes. This review aims to discuss the role of circulating miRNAs as potential diagnostic and prognostic biomarkers as well as therapeutic targets for estrogen-receptor negative breast cancers, HER2+ and triple negative.

Regulation of MicroRNA-497-Targeting AKT2 Influences Tumor Growth and Chemoresistance to Cisplatin in Lung Cancer

Background

MicroRNA-497 (miR-497) has been implicated in several cancers. Increasing studies demonstrate the role of AKT2 in cancers as an oncogene which is closely associated with tumor aggressiveness by enhancing cancer cell survival, migration and invasion However, miR-497/AKT2 axis in non-small cell lung cancer (NSCLC) remains unclear.

Methods

Quantitative real-time PCR (qRT-PCR) was used to quantify the expression of miR-497 and its target gene. The function of miR-497 in lung cancer was investigated through in vitro and in vivo assays (cell proliferation assay, cell migration assay, colony formation assay, flow cytometry assay, immunoblotting and tumorigenesis assay). Luciferase reporter assay was conducted to confirm the target gene of miR-497.

Results

In this study, we found that miR-497 was significantly downregulated in tumor tissues and blood samples of lung cancer patients. To understand the potential mechanism of miR-497 in inhibiting tumor growth, we showed that miR-497 blocked the activation of AKT2 and regulated cell proliferation, cell migration, colony formation and increases chemosensitivity of H1299 cells to cisplatin by inhibiting AKT2. MiR-497 also inhibited tumor growth and suppressed expression of AKT2 at the protein and mRNA levels in mouse xenograft tumors.

Conclusion

Taken together, our findings indicated that miR-497 suppresses the tumor growth by targeting AKT2, and the miR-497/AKT2 axis is a potential therapeutic target for NSCLC intervention.

EPAS1 targeting by miR-152-3p in Paclitaxel-resistant Breast Cancer

Background: Paclitaxel plays a pivotal role in the chemotherapy of breast cancer, but resistance to this drug is an important obstacle in the treatment. It is reported that microRNA-152-3p (miR-152-3p) is involved in tamoxifen resistance in breast cancer, but whether it is involved in paclitaxel resistance in breast cancer remains unknown. Materials and methods: We examined the expression of miR-152-3p in breast cancer tissues and cells by qRT-PCR. After transfecting paclitaxel-resistant MCF-7/TAX cells with miR-152-3p mimics, we analyzed the function of miR-152-3p in these cells by MTT assay and flow cytometry. We screened the target gene, endothelial PAS domain-containing protein 1 (EPAS1), using bioinformatics analysis and verified it with the dual luciferase reporter gene experiment. The relationship between EPAS1 and miR-152-3p and their roles in paclitaxel resistance of breast cancer were further investigated using RNA interference and transfection techniques. Results: The expression of miR-152-3p in normal breast tissues and cells was markedly higher than that in breast cancer. Overexpression of miR-152-3p decreased the survival rate and increased the apoptosis rate and sensitivity of MCF-7/TAX cells to paclitaxel. We confirmed that EPAS1 is the target of miR-152-3p and is negatively regulated by this miRNA. Moreover, transfection with EPAS1 siRNA enhanced the susceptibility and apoptosis rate of MCF-7/TAX cells to paclitaxel. Co-transfection of miR-152-3p mimics and EPAS1 increased paclitaxel sensitivity and apoptosis induced by the drug. Conclusion: miR-152-3p inhibits the survival of MCF-7/TAX cells and promotes their apoptosis by targeting the expression of EPAS1, thereby, enhancing the sensitivity of these breast cancer cells to paclitaxel.

Therapeutic Potential of Melatonin in the Regulation of MiR-148a-3p and Angiogenic Factors in Breast Cancer

BACKGROUND

The high mortality rate of breast cancer is related to the occurrence of metastasis, a process that is promoted by tumor angiogenesis. MicroRNAs are small molecules of noncoding mRNA that play a key role in gene regulation and are directly involved in the progression and angiogenesis of various tumor types, including breast cancer. Several miRNAs have been described as promoters or suppressors angiogenesis and may be associated with tumor growth and metastasis. Melatonin is an oncostatic agent with a capacity of modifying the expression of innumerable genes and miRNAs related to cancer.

OBJECTIVE

The aim of this study was to evaluate the role of melatonin and the tumor suppressor miR- 148a-3p on angiogenesis of breast cancer.

METHOD

MDA-MB-231 cells were treated with melatonin and modified with the overexpression of miR-148a-3p. The relative quantification in real-time of miR-148a-3p, IGF-IR and VEGF was performed by real-time PCR. The protein expression of these targets was performed by immunocytochemistry and immunohistochemistry. Survival, migration and invasion rates of tumor cells were evaluated. Finally, the xenograft model of breast cancer was performed to confirm the role of melatonin in the tumor.

RESULTS

The melatonin was able to increase the gene level of miR-148a-3p and decreased the gene and protein expression of IGF-1R and VEGF, both in vitro and in vivo. In addition, it also had an inhibitory effect on the survival, migration and invasion of breast tumor cells.

CONCLUSION

Our results confirm the role of melatonin in the regulation of miR-148a-3p and decrease of angiogenic factors.

Proangiogenic signature in advanced laryngeal carcinoma after microRNA expression profiling

The aim of this study is to evaluate which dysregulated angiomiRs compose the specific proangiogenic microRNA signature of advanced laryngeal cancer and review the literature. Thirty-six samples from twelve patients with advanced laryngeal carcinoma were collected. Total RNA was extracted and microRNA global profiling was performed using Agilent Technologies Microarray Kit. Fifty-nine microRNAs were found to have significantly different expression levels. Eleven microRNAs from the whole group were sorted as regulators of tumor angiogenesis (angiomiRs): seven were up-regulated-miR-1246, miR-181b 5p, miR-18a 5p, miR-21 3p, miR-210 3p, miR-503 5p, miR-93 5p and four were down-regulated-miR148a 5p, miR-145 5p, miR-204 5p, miR-125b 5p. For none of those microRNAs we found heterogeneity in tumor tissue. We are the first to report the specific proangiogenic microRNA signature in advanced laryngeal carcinoma and we confirm and amplify findings from previous studies that expand our perception of a specific "molecular state" of angiogenesis that is distinctive only for laryngeal cancer.

Sedentary and Trained Older Men Have Distinct Circulating Exosomal microRNA Profiles at Baseline and in Response to Acute Exercise

Exercise has multi-systemic benefits and attenuates the physiological impairments associated with aging. Emerging evidence suggests that circulating exosomes mediate some of the beneficial effects of exercise via the transfer of microRNAs between tissues. However, the impact of regular exercise and acute exercise on circulating exosomal microRNAs (exomiRs) in older populations remains unknown. In the present study, we analyzed circulating exomiR expression in endurance-trained elderly men (n = 5) and age-matched sedentary males (n = 5) at baseline (Pre), immediately after a forty minute bout of aerobic exercise on a cycle ergometer (Post), and three hours after this acute exercise (3hPost). Following the isolation and enrichment of exosomes from plasma, exosome-enriched preparations were characterized and exomiR levels were determined by sequencing. The effect of regular exercise on circulating exomiRs was assessed by comparing the baseline expression levels in the trained and sedentary groups. The effect of acute exercise was determined by comparing baseline and post-training expression levels in each group. Regular exercise resulted in significantly increased baseline expression of three exomiRs (miR-486-5p, miR-215-5p, miR-941) and decreased expression of one exomiR (miR-151b). Acute exercise altered circulating exomiR expression in both groups. However, exomiRs regulated by acute exercise in the trained group (7 miRNAs at Post and 8 at 3hPost) were distinct from those in the sedentary group (9 at Post and 4 at 3hPost). Pathway analysis prediction and reported target validation experiments revealed that the majority of exercise-regulated exomiRs are targeting genes that are related to IGF-1 signaling, a pathway involved in exercise-induced muscle and cardiac hypertrophy. The immediately post-acute exercise exomiR signature in the trained group correlates with activation of IGF-1 signaling, whereas in the sedentary group it is associated with inhibition of IGF-1 signaling. While further validation is needed, including measurements of IGF-1/IGF-1 signaling in blood or skeletal muscle, our results suggest that training status may counteract age-related anabolic resistance by modulating circulating exomiR profiles both at baseline and in response to acute exercise.

Regulatory Role of microRNAs in Tumor Angiogenesis

The process of neoangiogenesis is one of the classic hallmarks of a cancer. Its intricate mechanisms have long been one of the major domains in cancer research and a hope for a therapeutic breakthrough. Last decade a new subgroup of non-coding RNA molecules was reported called microRNAs. Literally hundreds of new molecules in this class are being uncovered as pivotal regulators in virtually all intracellular processes. The aim of this study is to classify and review those microRNA molecules that have a role in the processes of tumor angiogenesis and map their places in the regulatory framework of the classical proangiogenic genes and their canonical cascades.

Exosome Derived from Coronary Serum of Patients with Myocardial Infarction Promotes Angiogenesis Through the miRNA-143/IGF-IR Pathway

Purpose

Myocardial ischemia-reperfusion injury primarily causes myocardial infarction (MI), which is manifested by cell death. Angiogenesis is essential for repair and regeneration in cardiac tissue after MI. In this study, we aimed to investigate the effect of exosomes derived from the serum of MI patients in angiogenesis and its related mechanism.

Patients and Methods

Exosomes, isolated from serum, were collected from MI (MI-exosome) and control (Con-exosome) patients. After coculturing with human umbilical vein endothelial cells, MI-exosome promoted cell proliferation, migration, and tube formation.

Results

The results revealed that the production and release of MI-exosome were associated with cardiomyocytes. Moreover, microarray assays demonstrated that miRNA-143 was significantly decreased in MI-exosome. Meanwhile, the overexpression and knockdown of miRNA-143 could inhibit and enhance angiogenesis, respectively. Furthermore, the effect of exosomal miRNA-143 on angiogenesis was mediated by its targeting gene, insulin-like growth factor 1 receptor (IGF-IR), and was associated with the production of nitric oxide (NO).

Conclusion

Taken together, exosomes derived from the serum of patients with MI promoted angiogenesis through the IGF-IR/NO signaling pathway. The results provide novel understanding of the function of exosomes in MI.

Early Modulation of Circulating MicroRNAs Levels in HER2-Positive Breast Cancer Patients Treated with Trastuzumab-Based Neoadjuvant Therapy

Circulating microRNA (ct-miRNAs) are able to identify patients with differential response to HER2-targeted therapy. However, their dynamics are largely unknown. We assessed 752 miRNAs from 52 NeoALTTO patients with plasma pairs prior and two weeks after trastuzumab. Increased levels of ct-miR-148a-3p and ct-miR-374a-5p were significantly associated with pathological complete response (pCR) (p = 0.008 and 0.048, respectively). At a threshold ≥ the upper limit of the 95%CI of the mean difference, pCR resulted 45% (95%CI 24%–68%), and 44% (95%CI 22%–69%) for ct-miR-148a-3p and ct-miR-374a-5p, respectively. Notably, ct-miR-148a-3p retained its predictive value (OR 3.42, 95%CI 1.23–9.46, p = 0.018) in bivariate analysis along with estrogen receptor status. Combined information from ct-miR-148a-3p and ct-miR140-5p, which we previously reported to identify trastuzumab-responsive patients, resulted in greater predictive capability over each other, with pCR of 54% (95%CI 25%–81%) and 0% (95%CI 0%–31%) in ct-miR-148a/ct-miR-140-5p high/present and low/absent, respectively. GO and KEGG analyses showed common enriched terms between the targets of these ct-miRNAs, including cell metabolism regulation, AMPK and MAPK signaling, and HCC progression. In conclusion, early modulated ct-miR-148-3p may inform on the functional processes underlying treatment response, integrate the information from already available predictive biomarkers, and identify patients likely to respond to single agent trastuzumab-based neoadjuvant therapy.

Non-Coding RNAs as Regulators and Markers for Targeting of Breast Cancer and Cancer Stem Cells

Breast cancer is regarded as a heterogeneous and complicated disease that remains the prime focus in the domain of public health concern. Next-generation sequencing technologies provided a new perspective dimension to non-coding RNAs, which were initially considered to be transcriptional noise or a product generated from erroneous transcription. Even though understanding of biological and molecular functions of noncoding RNA remains enigmatic, researchers have established the pivotal role of these RNAs in governing a plethora of biological phenomena that includes cancer-associated cellular processes such as proliferation, invasion, migration, apoptosis, and stemness. In addition to this, the transmission of microRNAs and long non-coding RNAs was identified as a source of communication to breast cancer cells either locally or systemically. The present review provides in-depth information with an aim at discovering the fundamental potential of non-coding RNAs, by providing knowledge of biogenesis and functional roles of micro RNA and long non-coding RNAs in breast cancer and breast cancer stem cells, as either oncogenic drivers or tumor suppressors. Furthermore, non-coding RNAs and their potential role as diagnostic and therapeutic moieties have also been summarized.

Co-expression network analysis predicts a key role of microRNAs in the adaptation of the porcine skeletal muscle to nutrient supply

BACKGROUND

The role of non-coding RNAs in the porcine muscle metabolism is poorly understood, with few studies investigating their expression patterns in response to nutrient supply. Therefore, we aimed to investigate the changes in microRNAs (miRNAs), long intergenic non-coding RNAs (lincRNAs) and mRNAs muscle expression before and after food intake.

RESULTS

We measured the miRNA, lincRNA and mRNA expression levels in the gluteus medius muscle of 12 gilts in a fasting condition (AL-T0) and 24 gilts fed ad libitum during either 5 h. (AL-T1, N = 12) or 7 h. (AL-T2, N = 12) prior to slaughter. The small RNA fraction was extracted from muscle samples retrieved from the 36 gilts and sequenced, whereas lincRNA and mRNA expression data were already available. In terms of mean and variance, the expression profiles of miRNAs and lincRNAs in the porcine muscle were quite different than those of mRNAs. Food intake induced the differential expression of 149 (AL-T0/AL-T1) and 435 (AL-T0/AL-T2) mRNAs, 6 (AL-T0/AL-T1) and 28 (AL-T0/AL-T2) miRNAs and none lincRNAs, while the number of differentially dispersed genes was much lower. Among the set of differentially expressed miRNAs, we identified ssc-miR-148a-3p, ssc-miR-22-3p and ssc-miR-1, which play key roles in the regulation of glucose and lipid metabolism. Besides, co-expression network analyses revealed several miRNAs that putatively interact with mRNAs playing key metabolic roles and that also showed differential expression before and after feeding. One case example was represented by seven miRNAs (ssc-miR-148a-3p, ssc-miR-151-3p, ssc-miR-30a-3p, ssc-miR-30e-3p, ssc-miR-421-5p, ssc-miR-493-5p and ssc-miR-503) which putatively interact with the PDK4 mRNA, one of the master regulators of glucose utilization and fatty acid oxidation.

CONCLUSIONS

As a whole, our results evidence that microRNAs are likely to play an important role in the porcine skeletal muscle metabolic adaptation to nutrient availability.

Curcumol inhibits the proliferation and metastasis of melanoma via the miR-152-3p/PI3K/AKT and ERK/NF-κB signaling pathways

Melanoma is the most aggressive and treatment-resistant form of skin cancer. Curcumol is a Chinese medicinal herb traditionally used as a cancer remedy. However, the molecular mechanisms underlying the anticancer activity of curcumol in melanoma remains largely unknown. In the present study, we observed that Curcumol decreased mouse melanoma B16 cell proliferation and migration. The xenograft tumor assay showed that curcumol reduced melanoma volume and lung metastasis. Curcumol upregulated the expression of E-cadherin and downregulated the expression of N-cadherin, MMP2 and MMP9 in mouse melanoma B16 cell. Western blot analysis revealed that curcumol reduced the translocation of p65 to the nucleus and decreased p-ERK. Furthermore, curcumol attenuated c-MET, P13K and p-AKT protein expression and upregulated miR-152-3p gene expression. The dual-luciferase reporter assay indicated that c-MET was a target gene of miR-152-3p. Reduced expression of miR-152-3p partially attenuated the effect of curcumol on mouse melanoma B16 cell proliferation and migration. The decrease in c-MET, P13K and p-AKT protein expression following curcumol treatment in mouse melanoma B16 cells was notably attenuated by the miR-152-3p inhibitor. Taken together, our findings suggested that curcumol attenuated melanoma progression and concomitantly suppressed ERK/NF-κB signaling and promoted miR-152-3p expression to inactivate the c-MET/PI3K/AKT signaling pathway.

An update review of deregulated tumor suppressive microRNAs and their contribution in various molecular subtypes of breast cancer

BACKGROUND

Breast cancer (BC) is histologically classified into hormone-receptor+ (ER+, PR + ), human epidermal growth factor receptor-2+ (Her2 + ), and triple-negative breast cancer (TNBC) types. The important contribution of tumor-suppressive (TS) microRNAs (miRs) in BC development and treatment have been well-acknowledged in the literature.

OBJECTIVE

The present review focused on the contribution of recently examined TS miRs in the progression and treatment of various histological subtypes of BC.

RESULTS

In summary, various miRs have tumor-suppressive roles in BC, so that their aberrant expression leads to the abnormality in the cellular processes such as enhanced cell growth, decreased apoptosis, cell migration and metastasis, and decreased sensitivity to chemotherapy through deregulated expression of oncogene targets of TS miRs.

CONCLUSION

TS miRs could be regarded as a proper molecular target for target therapy of BC. However, further in vitro and in vivo investigations are required to confirm the exact molecular functions of TS miRs in BC cells to offer more efficient targeted therapies.

MicroRNAs in breast cancer: Roles, functions, and mechanism of actions

Breast cancer is one of the most lethal malignancies in women in the world. Various factors are involved in the development and promotion of the malignancy; most of them involve changes in the expression of certain genes, such as microRNAs (miRNAs). MiRNAs can regulate signaling pathways negatively or positively, thereby affecting tumorigenesis and various aspects of cancer progression, particularly breast cancer. Besides, accumulating data demonstrated that miRNAs are a novel tool for prognosis and diagnosis of breast cancer patients. Herein, we will review the roles of these RNA molecules in several important signaling pathways, such as transforming growth factor, Wnt, Notch, nuclear factor-κ B, phosphoinositide-3-kinase/Akt, and extracellular-signal-regulated kinase/mitogen activated protein kinase signaling pathways in breast cancer.

MicroRNA-148a/b-3p regulates angiogenesis by targeting neuropilin-1 in endothelial cells

MicroRNAs (miRs) are crucial regulators of vascular endothelial cell (EC) functions, including migration, proliferation, and survival. However, the role of most miRs in ECs remains unknown. Using RNA sequencing analysis, we found that miR-148a/b-3p expression was significantly downregulated during the differentiation of umbilical cord blood mononuclear cells into outgrowing ECs and that decreased miR-148a/b-3p levels were closely related to EC behavior. Overexpression of miR-148a/b-3p in ECs significantly reduced migration, filamentous actin remodeling, and angiogenic sprouting. Intriguingly, the effects of decreased miR-148a/b-3p levels were augmented by treatment with vascular endothelial growth factor (VEGF). Importantly, we found that miR-148a/b-3p directly regulated neuropilin-1 (NRP1) expression by binding to its 3′-untranslated region. In addition, because NRP1 is the coreceptor for VEGF receptor 2 (VEGFR2), overexpression of miR-148a/b-3p inhibited VEGF-induced activation of VEGFR2 and inhibited its downstream pathways, as indicated by changes to phosphorylated focal adhesion kinase (FAK), extracellular signal-regulated kinase (ERK), and p38 mitogen-activated protein kinase. Collectively, our results demonstrate that miR-148a/b-3p is a direct transcriptional regulator of NRP1 that mediates antiangiogenic pathways. These data suggest that miR-148a/b-3p is a therapeutic candidate for overcoming EC dysfunction and angiogenic disorders, including ischemia, retinopathy, and tumor vascularization.

A small regulatory RNA molecule helps prevent the development of new blood vessels, a finding that could have implications for the treatment of vascular disease and cancer. Young-Guen Kwon from Yonsei University in Seoul, South Korea, and colleagues cataloged all the microRNAs expressed during the differentiation of umbilical cord blood stem cells into precursors of the cells that line the inside of blood vessels. One microRNA in particular stood out for its association with cellular differentiation. The authors showed that this microRNA, called miR-148a/b-3p, directly binds part of the gene transcript encoding neuropilin-1, thereby blocking the production of this receptor for growth factors involved in new blood vessel formation. Modulating the activity of miR-148a/b-3p could have therapeutic value for disorders marked by aberrant blood vessel growth.

Apigenin Inhibits IL-6 Transcription and Suppresses Esophageal Carcinogenesis

Esophagus cancer is the seventh cause of cancer-related deaths globally. In this study, we analyzed interleukin 6 (IL-6) gene expression in human esophagus cancer patients and showed that IL-6 mRNA levels are significantly higher in tumor tissues and negatively correlated with overall survival, suggesting that IL-6 is a potential therapeutic target for esophagus cancer. We further demonstrated that apigenin, a nature flavone product of green plants, inhibited IL-6 transcription and gene expression in human esophagus cancer Eca-109 and Kyse-30 cells. Apigenin significantly and dose-dependently inhibited cell proliferation and promoted apoptosis while stimulating the cleaved PARP (poly ADP-ribose polymerase) (C-PARP) and caspase-8 expression. It suppressed VEGF (Vascular endothelial growth Factor) expression and tumor-induced angiogenesis. Pretreatment of cells with IL-6 could completely reverse apigenin-induced cellular changes. Finally, using a preclinical nude mice model subcutaneously xenografted with Eca-109 cells, we demonstrated the in vivo antitumor activity and mechanisms of apigenin. Taken together, this study revealed for the first time that apigenin is a new IL-6 transcription inhibitor and that inhibiting IL-6 transcription is one of the mechanisms by which apigenin exhibits its anticancer effects. The potential clinical applications of apigenin in treating esophagus cancer warrant further investigations.

Detailed Functional Characterization of a Waist-Hip Ratio Locus in 7p15.2 Defines an Enhancer Controlling Adipocyte Differentiation

We combined CAGE sequencing in human adipocytes during differentiation with data from genome-wide association studies to identify an enhancer in the SNX10 locus on chromosome 7, presumably involved in body fat distribution. Using reporter assays and CRISPR-Cas9 gene editing in human cell lines, we characterized the role of the enhancer in adipogenesis. The enhancer was active during adipogenesis and responded strongly to insulin and isoprenaline. The allele associated with increased waist-hip ratio in human genetic studies was associated with higher enhancer activity. Mutations of the enhancer resulted in less adipocyte differentiation. RNA sequencing of cells with disrupted enhancer showed reduced expression of established adipocyte markers, such as ADIPOQ and LPL, and identified CHI3L1 on chromosome 1 as a potential gene involved in adipocyte differentiation. In conclusion, we identified and characterized an enhancer in the SNX10 locus and outlined its plausible mechanisms of action and downstream targets.

•

An enhancer active during adipogenesis is located in an obesity GWAS locus

•

The enhancer responded strongly to insulin and isoprenaline

•

Mutation of the enhancer by CRISPR-Cas9 decreased adipocyte differentiation

•

Knockout of CHI3L1 decreased adipocyte differentiation

Overexpression of miR-148a inhibits viability and invasion of ovarian cancer OVCAR3 cells by targeting FOXO3

Decreased expression of microRNA (miR)-148a is associated with poor prognosis in ovarian cancer. The aim of the present study was to investigate the impact of miR-148a on tumor cell viability and invasion via targeting forkhead box protein O3 (FOXO3). Expression of miR-148a was detected in paired tumor and adjacent normal tissues. OVCAR3 cells were transfected with miR-148a mimic and inhibitor. Cell viability, apoptosis and invasion were determined. A luciferase reporter assay was used to study the association between miR-148a and FOXO3. In addition, the influence of miR-148a on tumor cell growth was investigated by performing xenograft assays in nude mice. RT-qPCR showed that miR-148a was downregulated in ovarian cancer tissues. Overexpression of miR-148a in OVCAR3 cells inhibited cell viability, suppressed invasion and promoted cellular apoptosis. The dual-luciferase assay indicated that miR-148a directly regulated the expression of FOXO3, a transcription factor of caspase-3. Western blotting confirmed that the expression of caspase-3 was regulated by the modulation of miR-148a expression. In vivo assays revealed that miR-148a overexpression inhibited the growth of OVCAR3 ×enograft tumors in nude mice. miR-148a is a tumor suppressor in ovarian cancer OVCAR3 cells and in nude mice. The suppressive effect is due to inhibiting cell viability and invasion as well as promoting apoptosis. These results may provide theoretical basis for targeting miR-148a in the treatment of ovarian cancer.

MicroRNA Regulation of Epigenetic Modifiers in Breast Cancer

Epigenetics refers to the heritable changes in gene expression without a change in the DNA sequence itself. Two of these major changes include aberrant DNA methylation as well as changes to histone modification patterns. Alterations to the epigenome can drive expression of oncogenes and suppression of tumor suppressors, resulting in tumorigenesis and cancer progression. In addition to modifications of the epigenome, microRNA (miRNA) dysregulation is also a hallmark for cancer initiation and metastasis. Advances in our understanding of cancer biology demonstrate that alterations in the epigenome are not only a major cause of miRNA dysregulation in cancer, but that miRNAs themselves also indirectly drive these DNA and histone modifications. More explicitly, recent work has shown that miRNAs can regulate chromatin structure and gene expression by directly targeting key enzymes involved in these processes. This review aims to summarize these research findings specifically in the context of breast cancer. This review also discusses miRNAs as epigenetic biomarkers and as therapeutics, and presents a comprehensive summary of currently validated epigenetic targets in breast cancer.

MicroRNA expression profile in retina and choroid in oxygen-induced retinopathy model

Background

Ischemic retinopathies (IRs) are leading causes of visual impairment. They are characterized by an initial phase of microvascular degeneration and a second phase of aberrant pre-retinal neovascularization (NV). microRNAs (miRNAs) regulate gene expression, and a number play a role in normal and pathological NV. But, post-transcriptional modulation of miRNAs in the eye during the development of IRs has not been systematically evaluated.

Aims & methods

Using Next Generation Sequencing (NGS) we profiled miRNA expression in the retina and choroid during vasodegenerative and NV phases of oxygen-induced retinopathy (OIR).

Results

Approximately 20% of total miRNAs exhibited altered expression (up- or down-regulation); 6% of miRNA were found highly expressed in retina and choroid of rats subjected to OIR. During OIR-induced vessel degeneration phase, miR-199a-3p, -199a-5p, -1b, -126a-3p displayed a robust decreased expression (> 85%) in the retina. While in the choroid, miR-152-3p, -142-3p, -148a-3p, -532-3p were upregulated (>200%) and miR-96-5p, -124-3p, -9a-3p, -190b-5p, -181a-1-3p, -9a-5p, -183-5p were downregulated (>70%) compared to controls. During peak pathological NV, miR-30a-5p, -30e-5p and 190b-5p were markedly reduced (>70%), and miR-30e-3p, miR-335, -30b-5p strongly augmented (by up to 300%) in the retina. Whereas in choroid, miR-let-7f-5p, miR-126a-5p and miR-101a-3p were downregulated by (>81%), and miR-125a-5p, let-7e-5p and let-7g-5p were upregulated by (>570%) during NV. Changes in miRNA observed using NGS were validated using qRT-PCR for the 24 most modulated miRNAs. In silico approach to predict miRNA target genes (using algorithms of miRSystem database) identified potential new target genes with pro-inflammatory, apoptotic and angiogenic properties.

Conclusion

The present study is the first comprehensive description of retinal/choroidal miRNAs profiling in OIR (using NGS technology). Our results provide a valuable framework for the characterization and possible therapeutic potential of specific miRNAs involved in ocular IR-triggered inflammation, angiogenesis and degeneration.

Suppression of miR-143 contributes to overexpression of IL-6, HIF-1α and NF-κB p65 in Cr(VI)-induced human exposure and tumor growth

Hexavalent chromium [Cr(VI)] is a known occupational and environmental contaminant and carcinogen, but new mechanisms of Cr(VI)-induced carcinogenesis remain to be elucidated. In this study, we found that expression of miR-143 is decreased, whereas that of Interleukin 6 (IL-6) is increased in blood samples of Cr(VI)-exposing workers compared with corresponding unexposed workers. In addition, IL-6 was increased in human bronchial epithelial cells (BEAS-Cr) exposed to Cr(VI) compared with unexposed BEAS-2B cells. To further investigate the mechanisms by which Cr(VI) promotes these changes, we assessed the effects of miR-143 on gene expression and found that miR-143 suppressed expression of IL-6, HIF-1α and NF-κB p65, and that inhibiting miR-143 promoted expression of IL-6, HIF-1α and NF-κB p65. Interestingly, IL-6 regulated expression of HIF-1α, and HIF-1α transcriptionally regulated expression of IL-6. Experiments in animals showed that miR-143 inhibited tumor growth and angiogenesis by regulating IL-6/HIF-1α and downstream signaling pathways in vivo. These outcomes support the hypothesis that the miR-143/IL-6/HIF-1α pathway functions to regulate Cr(VI)-induced carcinogenesis.

Up-regulation of miRNA-148a inhibits proliferation, invasion, and migration while promoting apoptosis of cervical cancer cells by down-regulating RRS1

The purpose of the present study is to figure out the role of miRNA-148a (miR-148a) in growth, apoptosis, invasion, and migration of cervical cancer cells by binding to regulator of ribosome synthesis 1 (RRS1). Cervical cancer and adjacent normal tissues, as well as cervical cancer cell line Caski, HeLa, C-33A, and normal cervical epithelial cell line H8 were obtained to detect the expression of miR-148a and RRS1. Relationship between miR-148a and RRS1 expression with clinicopathological characteristics was assessed. The selected Caski and HeLa cells were then transfected with miR-148a mimics, miR-148a inhibitors or RRS1 siRNA to investigate the role of miR-148a and RRS1 on proliferation, apoptosis, colony formation, invasion, and migration abilities of cervical cancer cells. Bioinformatics information and dual luciferase reporter gene assay was for used to detect the targetting relationship between miR-148a and RRS1. Down-regulated miR-148a and up-regulated RRS1 were found in cervical cancer tissues and cells. Down-regulated miR-148a and up-regulated RRS1 are closely related with prognostic factors of cervical cancer. RRS1 was determined as a target gene of miR-148a and miR-148a inhibited RRS1 expression in cervical cancer cells. Up-regulation of miR-148a inhibited cell proliferation, migration, and invasion while promoting apoptosis in Caski and HeLa cells. Our study suggests that miR-148a down-regulates RRS1 expression, thereby inhibiting the proliferation, migration, and invasion while promoting cell apoptosis of cervical cancer cells.

miR-148a inhibits early relapsed colorectal cancers and the secretion of VEGF by indirectly targeting HIF-1α under non-hypoxia/hypoxia conditions

Vascular endothelial growth factor (VEGF) is correlated with angiogenesis and early relapse of colorectal cancer (CRC). This study investigated the role of miR-148a in the regulation of VEGF/angiogenesis and early relapse of CRC. We established a stable clone with miR-148a expression in HCT116 and HT29 cell lines and created a hypoxic condition by using CoCl2 to determine the underlying mechanism of miR-148a. The effects of miR-148a on the phosphoryl-ERK (pERK)/hypoxia-inducible factor-1α (HIF-1α)/VEGF pathway were evaluated through Western blotting and the inhibitory effect of miR-148a on angiogenesis was demonstrated through a tube formation assay. Sixty-three CRC tissues (28 early relapse and 35 non-early relapse) were analysed to assess the relationship between miR-148a and HIF-1α/VEGF. The protein expression of pERK/HIF-1α/VEGF in HCT116 and HT29 cells was significantly decreased by miR-148a (all P < 0.05). The protein expression of VEGF/HIF-1α was strongly inversely associated with the expression of miR-148a in the 63 CRC tissue samples (all P < 0.05). Tube formation assay demonstrated that miR-148a significantly obliterated angiogenesis. miR-148a suppresses VEGF through down-regulation of the pERK/HIF-1α/VEGF pathway and might lead to the inhibition of angiogenesis; miR-148a down-regulation increased the early relapse rate of CRC. This demonstrates that miR-148a is a potential diagnostic and therapeutic target.

Non-coding RNAs as potential therapeutic targets in breast cancer

Paradigm shifting studies especially involving non-coding RNAs (ncRNAs) during last few decades have significantly changed the scientific perspectives regarding the complexity of cellular signalling pathways. Several studies have shown that the non-coding RNAs, initially ignored as transcriptional noise or products of erroneous transcription; actually regulate plethora of biological phenomena ranging from developmental processes to various diseases including cancer. Current strategies that are employed for the management of various cancers including that of breast fall short when their undesired side effects like Cancer Stem Cells (CSC) enrichment, low recurrence-free survival and development of drug resistance are taken into consideration. This review aims at exploring the potential role of ncRNAs as therapeutics in breast cancer, by providing a comprehensive understanding of their mechanism of action and function and their crucial contribution in regulating various aspects of breast cancer progression such as cell proliferation, angiogenesis, EMT, CSCs, drug resistance and metastasis. In addition, we also provide information about various strategies that can be employed or are under development to explore them as potential moieties that may be used for therapeutic intervention in breast cancer.

Assessment of miR-98-5p, miR-152-3p, miR-326 and miR-4289 Expression as Biomarker for Prostate Cancer Diagnosis

Prostate cancer (PCa) is one of the most commonly diagnosed cancers worldwide, accounting for almost 1 in 5 new cancer diagnoses in the US alone. The current non-invasive biomarker prostate specific antigen (PSA) has lately been presented with many limitations, such as low specificity and often associated with over-diagnosis. The dysregulation of miRNAs in cancer has been widely reported and it has often been shown to be specific, sensitive and stable, suggesting miRNAs could be a potential specific biomarker for the disease. Previously, we identified four miRNAs that are significantly upregulated in plasma from PCa patients when compared to healthy controls: miR-98-5p, miR-152-3p, miR-326 and miR-4289. This panel showed high specificity and sensitivity in detecting PCa (area under the curve (AUC) = 0.88). To investigate the specificity of these miRNAs as biomarkers for PCa, we undertook an in depth analysis on these miRNAs in cancer from the existing literature and data. Additionally, we explored their prognostic value found in the literature when available. Most studies showed these miRNAs are downregulated in cancer and this is often associated with cancer progression and poorer overall survival rate. These results suggest our four miRNA signatures could potentially become a specific PCa diagnostic tool of which prognostic potential should also be explored.

miR-148a regulates expression of the transferrin receptor 1 in hepatocellular carcinoma

Transferrin receptor 1 (TFR1) is a transmembrane glycoprotein that allows for transferrin-bound iron uptake in mammalian cells. It is overexpressed in various cancers to satisfy the high iron demand of fast proliferating cells. Here we show that in hepatocellular carcinoma (HCC) TFR1 expression is regulated by miR-148a. Within the TFR1 3′UTR we identified and experimentally validated two evolutionarily conserved miRNA response elements (MREs) for miR-148/152 family members, including miR-148a. Interestingly, analyses of RNA sequencing data from patients with liver hepatocellular carcinoma (LIHC) revealed a significant inverse correlation of TFR1 mRNA levels and miR-148a. In addition, TFR1 mRNA levels were significantly increased in the tumor compared to matched normal healthy tissue, while miR-148a levels are decreased. Functional analysis demonstrated post-transcriptional regulation of TFR1 by miR-148a in HCC cells as well as decreased HCC cell proliferation upon either miR-148a overexpression or TFR1 knockdown. We hypothesize that decreased expression of miR-148a in HCC may elevate transferrin-bound iron uptake, increasing cellular iron levels and cell proliferation.

Preliminary study on the role of miR‑148a and DNMT1 in the pathogenesis of acute myeloid leukemia

MicroRNA (miR)‑148a is differentially expressed in numerous malignant tumors and it was identified to regulate tumor growth, cell proliferation, apoptosis, angiogenesis and drug resistance via the regulation of the expression levels of its target genes. However, the biological function of miR‑148a in acute myeloid leukemia (AML) and its molecular mechanisms of action remain unclear. In the present study, the expression levels of miR‑148a and DNA methyltransferase 1 (DNMT1) were detected using reverse transcription‑quantitative polymerase chain reaction (PCR) and western blotting. Methylation‑specific PCR was used to detect the methylation levels in the miR‑148a promoter. The effects of miR‑148a on cell proliferation and apoptosis were assessed by Cell Counting kit‑8 or flow cytometry assays, respectively. A dual‑luciferase reporter assay was performed to investigate the association between miR‑148a and DNMT1. Patients with AML exhibited an increased expression level of miR‑148a, whereas the expression level of DNMT1 was identified to be decreased compared with healthy control subjects. In AML cell lines, the methylation state of miR‑148 promoter was significantly increased compared with normal cells. Following knockdown of DNMT1 in U937 cells, the expression level of miR‑148a increased significantly, whereas the methylation level of the miR‑148a promoter decreased. The mRNA and protein expression levels of DNMT1 decreased following transfection with miR‑148a mimics in U937 cells. Conversely, transfection with miR‑148a inhibitor in Kasumi‑1 cells led to an increase in the expression level of DNMT. Dual‑luciferase reporter assays suggested that DNMT1 was one of the direct target genes of miR‑148a. Overexpression of miR‑148a inhibited cell proliferation and promoted apoptosis. Inhibition of DNMT1 led to a decreased methylation level of the 5'‑cytosine‑phosphate‑guanine‑3' islands in the miR‑148a promoter, thus increasing the expression level of miR‑148a. DNMT1 was identified to be a downstream target of miR‑148a, and was negatively regulated by miR‑148a in AML cell lines, suggesting that miR‑148a and DNMT1 form a mutual negative feedback loop.

Retracted Article: MiR-148a agomir based targeting of c-Met and Her-3 is able to attenuate EGFR-T790M mutation driven gefitinib and erlotinib resistance in non-small cell lung cancer cells

MiR-148a inhibits NSCLC progression. Whether miR-148a would reduce EGFR tyrosine kinase inhibitor (TKI) resistance of NSCLC cells remains underexplored. In this study, 5 NSCLC patients received surgery and gefitinib treatment but developed pleural metastasis. Patients' NSCLC adopted EGFR T790M mutation. 5 naïve and 5 gefitinib-resisting NSCLC cell lines were derived from patients primary and metastatic tumor tissues, and the 5 gefitinib-resisting NSCLC cell lines were trained with erlotinib to establish the erlotinib-resisting cell lines. MiR-148a levels in cells were analyzed by qRT-PCR. miR-148a overexpression was mimicked by agomir treatment. NSCLC cell malignancy was evaluated by cell proliferation, apoptosis, colony formation and transwell invasion assays. Protein levels of c-Met, Her-3 and IGF-1R were assessed by western blotting. miRNA-mRNA interaction was investigated by luciferase reporter assay and AGO2-RIP. Transient overexpression of MET, ERBB3 or IGF1R gene was achieved by plasmid transfection. Results showed that the MiR-148a level was decreased with the development of gefitinib and erlotinib resistance and that there was an increase in malignancy in NSCLC cells in vitro. Treatment with miR-148a agomir significantly enhanced the cytotoxicity of gefitinib and erlotinib to naïve, gefitinib-resisting and erlotinib-resisting NSCLC cells in vitro while reducing their protein levels of c-Met, Her-3 and IGF-1R, the mRNAs of which were verified as direct targets of miR-148a in NSCLC cells. Restoring c-Met or Her-3 protein levels partially reduced the gefitinib and erlotinib sensitizing effect of miR-148a agomir treatment on NSCLC cells. We concluded that MiR-148a attenuated gefitinib and erlotinib resistance in non-small cell lung cancer cells with EGFR T790M mutation by targeting c-Met and Her-3 expression.

MiR-148a inhibits NSCLC progression.

Downregulation of miR-152 contributes to DNMT1-mediated silencing of SOCS3/SHP-1 in non-Hodgkin lymphoma

Understanding the molecular mechanisms for the development of non-Hodgkin lymphoma (NHL) will improve our ability to cure the patients. qRT-PCR was applied for the examination of the efficiency of shRNA for DNMT1, the expression of suppressor genes, miRNA-152. The MTT analysis, cell cycle analysis, clonal formation, and apoptotic analysis were used to examine the functions of DNMT1 and miR-152 in lymphoma cells. Methylation-specific polymerase chain reaction (MSP) was used to examine the methylation of tumor suppressor genes. The dual luciferase assay and western blot were used to validate if DNMT1 is the target of miR-152. For the in vivo experiments, the lymphoma cells were injected into the nude mice for quantification of the tumor growth after transfection of miR-152 mimics. Knockdown of DNMT1 by shRNA (sh-DNMT1) in OCI-Ly10 and Granta-159 cells significantly upregulated the expression of tumor suppressor genes (SOCS3, BCL2L10, p16, p14, and SHP-1) via decreasing their methylation level. At the cellular level, we found sh-DNMT1 inhibited the proliferation, clonal formation and cell cycle progression and induced the cell apoptosis of lymphoma cells. Furthermore, we found miR-152 can downregulates the expression of DNMT1 via directly targeting the gene. Overexpression of miR-152 also increased the expression of tumor suppressor genes SOCS3 and SHP-1. And miR-152 also can inhibit the cell proliferation and induce the cell apoptosis. Moreover, we found overexpression of miR-152 significantly repressed the tumor growth with decreased DNMT1 expression and increased expression of tumor suppressor genes in vivo. Our study demonstrates that miR-152 can inhibit lymphoma growth via suppressing DNMT1-mediated silencing of SOCS3 and SHP-1. These data demonstrate a new mechanism for the development of NHL and this may provide a new therapeutic target for NHL.

The pro-metastasis effect of circANKS1B in breast cancer

Background

Recent studies indicate that circular RNA (circRNA) plays a pivotal role in cancer progression. Here, we sought to investigate its role in breast cancer.

Methods

CircANKS1B (a circRNA originated from exons 5 to 8 of the ANKS1B gene, hsa_circ_0007294) was identified by RNA-sequencing and validated by qRT-PCR and Sanger sequencing. Clinical breast cancer samples were used to evaluate the expression of circANKS1B and its associations with clinicopathological features and prognosis. Gain- and loss-of-function experiments in cell lines and mouse xenograft models were performed to support clinical findings and elucidate the function and underlying mechanisms of circANKS1B in breast cancer.

Results

CircANKS1B was significantly up-regulated in triple-negative breast cancer (TNBC) compared with non-TNBC tissues and cell lines. Increased circANKS1B expression was closely associated with lymph node metastasis and advanced clinical stage and served as an independent risk factor for overall survival of breast cancer patients. Functional studies revealed that circANKS1B promoted breast cancer invasion and metastasis both in vitro and in vivo by inducing epithelial-to-mesenchymal transition (EMT), while had no effect on breast cancer growth. Mechanistically, circANKS1B abundantly sponged miR-148a-3p and miR-152-3p to increase the expression of transcription factor USF1, which could transcriptionally up-regulate TGF-β1 expression, resulting in activating TGF-β1/Smad signaling to promote EMT. Moreover, we found that circANKS1B biogenesis in breast cancer was promoted by splicing factor ESRP1, whose expression was also regulated by USF1.

Conclusions

Our data uncover an essential role of the novel circular RNA circANKS1B in the metastasis of breast cancer, which demonstrate that therapeutic targeting of circANKS1B may better prevent breast cancer metastasis.

Electronic supplementary material

The online version of this article (10.1186/s12943-018-0914-x) contains supplementary material, which is available to authorized users.

Hypoxia-mediated mitochondria apoptosis inhibition induces temozolomide treatment resistance through miR-26a/Bad/Bax axis

Glioblastoma multiforme (GBM) is one of the most hypoxic tumors of the central nervous system. Although temozolomide (TMZ) is an effective clinical agent in the GBM therapy, the hypoxic microenvironment remains a major barrier in glioma chemotherapy resistance, and the underlying mechanisms are poorly understood. Here, we find hypoxia can induce the protective response to mitochondrion via HIF-1α-mediated miR-26a upregulation which is associated with TMZ resistance in vitro and in vivo. Further, we demonstrated that HIF-1α/miR-26a axis strengthened the acquisition of TMZ resistance through prevention of Bax and Bad in mitochondria dysfunction in GBM. In addition, miR-26a expression levels negatively correlate with Bax, Bad levels, and GBM progression; but highly correlate with HIF-1α levels in clinical cancer tissues. These findings provide a new link in the mechanistic understanding of TMZ resistance under glioma hypoxia microenvironment, and consequently HIF-1α/miR-26a/Bax/Bad signaling pathway as a promising adjuvant therapy for GBM with TMZ.

Restoration of miR-152 expression suppresses cell proliferation, survival, and migration through inhibition of AKT-ERK pathway in colorectal cancer

BACKGROUND

MiR-152 has been reported as a tumor suppressor microRNA that is downregulated in a number of cancers, including colorectal cancer (CRC). A recent study suggested that miR-152 could be one of the key regulators of CRC. The aim of this study is to investigate the role of miR-152 in CRC and its mechanisms.

METHODS

The pCMV-GPF-miR-152 vector was transfected into SW-480 and HCT-116 CRC cells via JetPEI transfection reagent. The stable miR-152-expressed cells were selected for the further experiment. To evaluate the effect of miR-152 on cell proliferation, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed. Also, the effect of miR-152 on the survival of CRC cells was analyzed using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. The inhibitory effect of miR-152 on migration was assessed by wound healing scratch assay. Then, the proteins expression levels of protein kinase B (AKT), phosphorylated AKT (p-AKT), extracellular signal-regulated kinase (ERK), and phosphorylated ERK (p-ERK) were measured by the western blot analysis method.

RESULTS

The result of MTT assay represented miR-152 could inhibit cell proliferation. The TUNEL assay showed miR-152 could induce apoptosis in CRC cells. The wound healing scratch assay showed that miR-152 replacement repressed cell migration in CRC cell lines compared to control groups. The result of protein expression by western blot analysis demonstrated that miR-152 could reduce AKT-p-AKT, and ERK-p-ERK ratio compared to control cells.

CONCLUSION

Our results show that miR-152 has new anticancer and antimetastatic effect in CRC tissue. The current study showed that miR-152 could be a novel therapeutic small molecule to suppress CRC cell proliferation, survival, and migration by suppressing AKT-ERK signaling pathways.

Melatonin restrains angiogenic factors in triple-negative breast cancer by targeting miR-152-3p: In vivo and in vitro studies

AIMS

Breast cancer represents the second most prevalent tumor-related cause of death among women. Although studies have already been published regarding the association between breast tumors and miRNAs, this field remains unclear. MicroRNAs (miRNAs) are defined as non-coding RNA molecules, and are known to be involved in cell pathways through the regulation of gene expression. Melatonin can regulate miRNAs and genes related with angiogenesis. This hormone is produced naturally by the pineal gland and presents several antitumor effects. The aim of this study was to understand the action of melatonin in the regulation of miRNA-152-3p in vivo and in vitro.

MAIN METHODS

In order to standardize the melatonin treatment in the MDA-MB-468 cells, we carried out the cell viability assay at different concentrations. PCR Array plates were used to identify the differentiated expression of miRNAs after the treatment with melatonin. The relative quantification of the target gene expression (IGF-IR, HIF-1α and VEGF) was performed by real-time PCR. For the tumor development, MDA-MB-468 cells were implanted in female BALB/c mice, and treated or not treated with melatonin. Moreover, the quantification of the target genes protein expression was performed by immunocytochemistry and immunohistochemistry.

KEY FINDINGS

Relative quantification shows that the melatonin treatment increases the gene expression of miR-152-3p and the target genes, and decreased protein levels of the genes both in vitro and in vivo.

SIGNIFICANCE

Our results confirm the action of melatonin on the miR-152-3p regulation known to be involved in the progression of breast cancer.

Somatostatin Analogue Treatment Primarily Induce miRNA Expression Changes and Up-Regulates Growth Inhibitory miR-7 and miR-148a in Neuroendocrine Cells

Somatostatin (SST) analogues are used to control the proliferation and symptoms of neuroendocrine tumors (NETs). MicroRNAs (miRNA) are small non-coding RNAs that modulate posttranscriptional gene expression. We wanted to characterize the miRNAs operating under the control of SST to elucidate to what extent they mediate STT actions. NCI-H727 carcinoid cell line was treated with either a chimeric SST/dopamine analogue; a SST or dopamine analogue for proliferation assays and for identifying differentially expressed miRNAs using miRNA microarray. The miRNAs induced by SST analogue treatment are investigated in carcinoid cell lines NCI-H727 and CNDT2 using in situ hybridization, qPCR and proliferation assays. SST analogues inhibited the growth of carcinoid cells more potently compared to the dopamine analogue. Principal Component Analysis (PCA) of the samples based on miRNA expression clearly separated the samples based on treatment. Two miRNAs which were highly induced by SST analogues, miR-7 and miR-148a, were shown to inhibit the proliferation of NCI-H727 and CNDT2 cells. SST analogues also produced a general up-regulation of the let-7 family members. SST analogues control and induce distinct miRNA expression patterns among which miR-7 and miR-148a both have growth inhibitory properties.

Quantitative proteomic analysis of the miR-148a-associated mechanisms of metastasis in non-small cell lung cancer

MicroRNAs (miRs) are small non-coding RNAs that regulate gene expression and protein synthesis. Our previous study demonstrated that miR-148a suppressed the metastasis of non-small cell lung cancer (NSCLC) in vitro and in vivo. However, the modulatory mechanism of this effect remains unclear. In the present study, quantitative proteomic technology was used to study the protein expression profile of SPC-A-1 cells subsequent to the downregulation of miR-148a expression, in order to elucidate the molecular mechanism of the suppression of NSCLC metastasis by miR-148a. The differentially expressed proteins identified were analyzed using bioinformatics tools, including the Database for Annotation, Visualization and Integrated Discovery and the Search Tool for the Retrieval of Interacting Genes/proteins. In two experiments, 4,048 and 4,083 proteins were identified, and 4,014 and 4,039 proteins were quantified, respectively. In total, 44 proteins were upregulated and 40 proteins were downregulated. This was verified at the protein and mRNA levels by western blotting and reverse transcription-quantitative polymerase chain reaction, respectively. Bioinformatics analysis was used to identify potential interactions and signaling networks for the differentially expressed proteins. This may have provided an appropriate perspective for the comprehensive analysis of the modulatory mechanism underlying the metastasis-suppressive effects of miR-148a in NSCLC. In conclusion, quantitative proteomic technology revealed that miR-148a may regulate a panel of tumor-associated proteins to suppress metastasis in NSCLC.

MicroRNA-Dependent Regulation of IGF1R Gene Expression in Hormone-Sensitive and Hormone-Resistant Prostate Cancer Cells

Using multiple parallel sequencing on Illumina platform, we identified eight microRNAs that showed significant opposite changes of gene expression in cells of the hormone-sensitive LNCaP prostate cancer cell line and in cells of the hormone-resistant DU-145 cell line, in comparison to the microRNA expression in the normal prostate tissue cells. We found that the insulin-like growth factor 1 receptor (IGF1R) gene is a target of five microRNAs whose expression is increased in LNCaP cells and reduced in DU-145 cells.