miR-216a may inhibit pancreatic tumor growth by targeting JAK2

Using microRNAs Networks to Understand Pancreatic Cancer-A Literature Review

Pancreatic cancer is a severe disease, challenging to diagnose and treat, and thereby characterized by a poor prognosis and a high mortality rate. Pancreatic ductal adenocarcinoma (PDAC) represents approximately 90% of pancreatic cancer cases, while other cases include neuroendocrine carcinoma. Despite the growing knowledge of the pathophysiology of this cancer, the mortality rate caused by it has not been effectively reduced. Recently, microRNAs have aroused great interest among scientists and clinicians, as they are negative regulators of gene expression, which participate in many processes, including those related to the development of pancreatic cancer. The aim of this review is to show how microRNAs (miRNAs) affect key signaling pathways and related cellular processes in pancreatic cancer development, progression, diagnosis and treatment. We included the results of in vitro studies, animal model of pancreatic cancer and those performed on blood, saliva and tumor tissue isolated from patients suffering from PDAC. Our investigation identified numerous dysregulated miRNAs involved in KRAS, JAK/STAT, PI3/AKT, Wnt/β-catenin and TGF-β signaling pathways participating in cell cycle control, proliferation, differentiation, apoptosis and metastasis. Moreover, some miRNAs (miRNA-23a, miRNA-24, miRNA-29c, miRNA-216a) seem to be engaged in a crosstalk between signaling pathways. Evidence concerning the utility of microRNAs in the diagnosis and therapy of this cancer is poor. Therefore, despite growing knowledge of the involvement of miRNAs in several processes associated with pancreatic cancer, we are beginning to recognize and understand their role and usefulness in clinical practice.

MicroRNA Signatures for Pancreatic Cancer and Chronic Pancreatitis: Expression Profiling by NGS

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a deadly disease due to the lack of early detection. Because chronic pancreatitis (CP) patients are a high-risk group for pancreatic cancer, this study aimed to assess the differential miRNA profile in pancreatic tissue of patients with CP and pancreatic cancer.

METHODS

MiRNAs were isolated from formalin-fixed paraffin-embedded pancreatic tissue of 22 PDAC patients, 18 CP patients, and 10 normal pancreatic tissues from autopsy (C) cases and processed for next-generation sequencing. Known and novel miRNAs were identified and analyzed for differential miRNA expression, target prediction, and pathway enrichment between groups.

RESULTS

Among the miRNAs identified, 166 known and 17 novel miRNAs were found exclusively in PDAC tissues, while 106 known and 10 novel miRNAs were found specifically in CP tissues. The pathways targeted by PDAC-specific miRNAs and differentially expressed miRNAs between PDAC versus CP tissues and PDAC versus control tissues were the proteoglycans pathway, Hippo signaling pathway, adherens junction, and transforming growth factor-β signaling pathway.

CONCLUSIONS

This study resulted in a set of exclusive and differentially expressed miRNAs in PDAC and CP can be assessed for their diagnostic value. In addition, studying the role of miRNA-target gene interactions in carcinogenesis may open new therapeutic avenues.

The role of CEMIP in cancers and its transcriptional and post-transcriptional regulation

CEMIP is a protein known for inducing cell migration and binding to hyaluronic acid. Functioning as a hyaluronidase, CEMIP primarily facilitates the breakdown of the extracellular matrix component, hyaluronic acid, thereby regulating various signaling pathways. Recent evidence has highlighted the significant role of CEMIP in different cancers, associating it with diverse pathological states. While identified as a biomarker for several diseases, CEMIP's mechanism in cancer seems distinct. Accumulating data suggests that CEMIP expression is triggered by chemical modifications to itself and other influencing factors. Transcriptionally, chemical alterations to the CEMIP promoter and involvement of transcription factors such as AP-1, HIF, and NF-κB regulate CEMIP levels. Similarly, specific miRNAs have been found to post-transcriptionally regulate CEMIP. This review provides a comprehensive summary of CEMIP's role in various cancers and explores how both transcriptional and post-transcriptional mechanisms control its expression.

Investigating the regulatory role of miRNAs as silent conductors in the management of pathogenesis and therapeutic resistance of pancreatic cancer

Pancreatic cancer (PC) has the greatest mortality rate of all the main malignancies. Its advanced stage and poor prognosis place it at the bottom of all cancer sites. Hence, emerging biomarkers can enable precision medicine where PC therapy is tailored to each patient. This highlights the need for new, highly sensitive and specific biomarkers for early PC diagnosis. Prognostic indicators are also required to stratify PC patients. To avoid ineffective treatment, adverse events, and expenses, biomarkers are also required for patient monitoring and identifying responders to treatment. There is substantial evidence that microRNAs (miRs, miRNAs) play a critical role in regulating mRNA and, as a consequence, protein expression in normal and malignant tissues. Deregulated miRNA profiling in PC can help with diagnosis, treatment planning, and prognosis. Furthermore, knowledge of the primary effector genes and downstream pathways in PC can help pinpoint potential miRNAs for use in treatment. Different miRNA expression profiles may serve as diagnostic, prognostic markers, and therapeutic targets across the spectrum of malignant pancreatic illness. Dysregulation of miRNAs has been linked to the malignant pathophysiology of PC through affecting many cellular functions such as increasing invasive and proliferative prospect, supporting angiogenesis, cell cycle aberrance, apoptosis elusion, metastasis promotion, and low sensitivity to particular treatments. Accordingly, in the current review, we summarize the recent advances in the roles of oncogenic and tumor suppressor (TS) miRNAs in PC and discuss their potential as worthy diagnostic and prognostic biomarkers for PC, as well as their significance in PC pathogenesis and anticancer drug resistance.

Molecular mechanisms of microRNA-216a during tumor progression

MicroRNAs (miRNAs) as the members of non-coding RNAs family are involved in post-transcriptional regulation by translational inhibiting or mRNA degradation. They have a critical role in regulation of cell proliferation and migration. MiRNAs aberrations have been reported in various cancers. Considering the importance of these factors in regulation of cellular processes and their high stability in body fluids, these factors can be suggested as suitable non-invasive markers for the cancer diagnosis. MiR-216a deregulation has been frequently reported in different cancers. Therefore, in the present review we discussed the molecular mechanisms of the miR-216a during tumor progression. It has been reported that miR-216a mainly functioned as a tumor suppressor through the regulation of signaling pathways and transcription factors. This review paves the way to suggest the miR-216a as a probable therapeutic and diagnostic target in cancer patients.

Epi-miRNAs: Regulators of the Histone Modification Machinery in Human Cancer

Cancer is a leading cause of death and disability worldwide. Epigenetic deregulation is one of the most critical mechanisms in carcinogenesis and can be classified into effects on DNA methylation and histone modification. MicroRNAs are small noncoding RNAs involved in fine-tuning their target genes after transcription. Various microRNAs control the expression of histone modifiers and are involved in a variety of cancers. Therefore, overexpression or downregulation of microRNAs can alter cell fate and cause malignancies. In this review, we discuss the role of microRNAs in regulating the histone modification machinery in various cancers, with a focus on the histone-modifying enzymes such as acetylases, deacetylases, methyltransferases, demethylases, kinases, phosphatases, desumoylases, ubiquitinases, and deubiquitinases. Understanding of microRNA-related aberrations underlying histone modifiers in pathogenesis of different cancers can help identify novel therapeutic targets or early detection approaches that allow better management of patients or monitoring of treatment response.

Pediatric brain tumor cell lines exhibit miRNA-depleted, Y RNA-enriched extracellular vesicles

BACKGROUND

Medulloblastoma (MB) and diffuse infiltrative pontine glioma (DIPG) are malignant pediatric tumors. Extracellular vesicles (EVs) and their bioactive cargoes have been implicated in tumorigenesis. Most studies have focused on adult tumors, therefore the role of EVs and the noncoding RNA (ncRNA) landscape in pediatric brain tumors is not fully characterized. The overall aim of this pilot study was to isolate EVs from MB and DIPG patient-derived cell lines and to explore the small ncRNA transcriptome.

METHODS

EVs from 3 DIPG and 4 MB patient-derived cell lines were analyzed. High-throughput next generation sequencing interrogated the short non-coding RNA (ncRNA) transcriptome. Known and novel miRNAs were quantified. Differential expression analysis, in silico target prediction, and functional gene enrichment were performed.

RESULTS

EV secretomes from MB and DIPG patient-derived cell lines demonstrated discrete ncRNA biotypes. Notably, miRNAs were depleted and Y RNAs were enriched in EV samples. Hierarchical cluster analysis revealed high discrimination in miRNA expression between DIPG and MB cell lines and RNA-Seq identified novel miRNAs not previously implicated in MB or DIPG pathogenesis. Known and putative target genes of dysregulated miRNAs were identified. Functional annotation analysis of the target genes for differentially expressed EV-and parental-derived miRNAs revealed significant cancer-related pathway involvement.

CONCLUSIONS

This hypothesis-generating study demonstrated that pediatric brain tumor-derived cell lines secrete EVs comprised of various ncRNA cargoes. Validation of these findings in patient samples may provide new insights into the pediatric brain tumor microenvironment and identification of novel therapeutic candidates.

Upregulation of miR-216a-5p by Lentinan Targeted Inhibition of JAK2/STAT3 Signaling Pathway to Reduce Lung Adenocarcinoma Cell Stemness, Promote Apoptosis, and Slow Down the Lung Adenocarcinoma Mechanisms

To investigate the effect of Lentinan (LNT) on lung adenocarcinoma (LUAD) cell stemness and its mechanism. In this study, we founded that LNT significantly reduce the cell proliferation, activity, migration, invasion, and stemness of LUAD cells, and promote their apoptosis compared with the control group in vitro. Moreover, LNT significantly inhibited the volume and weight of tumors of nude mice in vivo. At the same time, LNT can significantly up-regulate miR-216a-5p levels and reduce the protein expression of phospho-JAK2 (Y1007/1008) and phospho-STAT3 (Tyr705), thereby inhibiting the JAK2/STAT3 signaling pathway. Interfering with miR-216a-5p expression and activating the JAK2/STAT3 signaling pathway can significantly reverse LNT inhibitory effects on LUAD. Collectively, LNT can inhibit the JAK2/STAT3 signaling pathway by up-regulating miR-216a-5p, reducing stemness, and promoting LUAD cells apoptosis, then slow down LUAD occurrence and development, providing concepts and experimental foundation treating patients with LUAD.

Deletion of pancreas-specific miR-216a reduces beta-cell mass and inhibits pancreatic cancer progression in mice

miRNAs have crucial functions in many biological processes and are candidate biomarkers of disease. Here, we show that miR-216a is a conserved, pancreas-specific miRNA with important roles in pancreatic islet and acinar cells. Deletion of miR-216a in mice leads to a reduction in islet size, β-cell mass, and insulin levels. Single-cell RNA sequencing reveals a subpopulation of β-cells with upregulated acinar cell markers under a high-fat diet. miR-216a is induced by TGF-β signaling, and inhibition of miR-216a increases apoptosis and decreases cell proliferation in pancreatic cells. Deletion of miR-216a in the pancreatic cancer-prone mouse line KrasG12D;Ptf1aCreER reduces the propensity of pancreatic cancer precursor lesions. Notably, circulating miR-216a levels are elevated in both mice and humans with pancreatic cancer. Collectively, our study gives insights into how β-cell mass and acinar cell growth are modulated by a pancreas-specific miRNA and also suggests miR-216a as a potential biomarker for diagnosis of pancreatic diseases.

Long noncoding RNA TTTY15 promotes growth and metastasis of esophageal squamous cell carcinoma by sponging microRNA-337-3p to upregulate the expression of JAK2

Long noncoding RNA (lncRNA) testis-specific transcript, Y-linked 15 (TTTY15) plays an important regulatory role in prostate cancer, but its role in esophageal squamous cell carcinoma (ESCC) remains unclear. This study aimed to explore the expression pattern, biological function and underlying mechanism of TTTY15 in ESCC. Quantitative real-time PCR (qRT-PCR) was used to detect the expression of TTTY15 and microRNA (miR)-337-3p in ESCC tissues and cell lines. Cell counting kit-8 method was used to detect the proliferation of ESCC cells. Transwell method was used to determine the migration and invasion of ESCC cells. Luciferase reporter assay was used to verify the interaction between TTTY15 and miR-337-3p. Western blot was used to analyze the effects of TTTY15 and miR-337-3p on Janus kinase 2 (JAK2) expression. In the present study, we demonstrated that the expression level of TTTY15 was significantly upregulated in ESCC tissues, while the expression of miR-337-3p was downregulated. In ESCC samples, the expression levels of TTTY15 and miR-337-3p were negatively correlated. TTTY15 knockdown could significantly reduce the proliferation, migration and invasion of ESCC cells, and miR-337-3p mimics had similar effects. In addition, overexpression of TTTY15 inhibited miR-337-3p by binding with it. TTTY15 could indirectly modulate JAK2, and overexpression of TTTY15 could reverse the inhibitory effects of miR-337-3p on malignant phenotypes of ESCC cells. In conclusion, TTTY15 plays an oncogenic role in ESCC by targeting miR-337-3p/JAK2 axis.

Long Non-coding RNAs: Potential Players in Cardiotoxicity Induced by Chemotherapy Drugs

One of the most important side effects of chemotherapy is cardiovascular complications, such as cardiotoxicity. Many factors are involved in the pathogenesis of cardiotoxicity; one of the most important of which is long non-coding RNAs (lncRNAs). lncRNA has 200-1000 nucleotides. It is involved in important processes such as cell proliferation, regeneration and apoptosis; today it is used as a prognostic and diagnostic factor. A, various drugs by acting on lncRNAs can affect cells. Therefore, by accurately identifying IncRNAs function, we can play an effective role in preventing the development of cardiotoxicity-induced chemotherapy drugs, and use them as a therapeutic strategy to improve clinical symptoms and increase patient survival.

MicroRNA-216a targets WT1 expression and regulates KRT7 transcription to mediate the progression of pancreatic cancer-A transcriptome analysis

Gene expression profiling has been broadly performed in the field of cancer research. This study aims to explore the key gene regulatory network and focuses on the functions of microRNA (miR)-216a in pancreatic cancer (PC). PC datasets GSE15471, GSE16515, and GSE32676 were used to screen the differentially expressed genes (DEGs) in PC. A miRNA microarray analysis and gene oncology analysis suggested miR-216a as an important differentially expressed miRNA in PC. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis suggested that miR-216a and the DEGs are largely enriched on the phosphatidyl inositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway. miR-216a targeted Wilms Tumor 1 (WT1), while WT1 promoted transcription activity of keratin 7 (KRT7). Upregulation of miR-216a reduced proliferation and invasiveness of PC cells, while further upregulation of WT1 blocked the functions of miR-216a. Silencing of KRT7 diminished the oncogenic role of WT1. The in vitro results were reproduced in vivo. High expression of miR-216a while poor expression of WT1 indicated better prognosis of PC patients. The miR-216a/WT1/KRT7 axis influenced the activity of the PI3K/AKT pathway. To conclude, this study evidenced that miR-216a suppressed WT1 expression and blocked KRT7 transcription, which inactivated the PI3K/AKT signaling and reduced PC progression.

MicroRNA-Regulated Signaling Pathways: Potential Biomarkers for Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is the most aggressive and invasive type of pancreatic cancer (PCa) and is expected to be the second most common cause of cancer-associated deaths. The high mortality rate is due to the asymptomatic progression of the clinical features until the advanced stages of the disease and the limited effectiveness of the current therapeutics. Aberrant expression of several microRNAs (miRs/miRNAs) has been related to PDAC progression and thus they could be potential early diagnostic, prognostic, and/or therapeutic predictors for PDAC. miRs are small (18 to 24 nucleotides long) non-coding RNAs, which regulate the expression of key genes by targeting their 3′-untranslated mRNA region. Increased evidence has also suggested that the chemoresistance of PDAC cells is associated with metabolic alterations. Metabolic stress and the dysfunctionality of systems to compensate for the altered metabolic status of PDAC cells is the foundation for cellular damage. Current data have implicated multiple systems as hallmarks of PDAC development, such as glutamine redox imbalance, oxidative stress, and mitochondrial dysfunction. Hence, both the aberrant expression of miRs and dysregulation in metabolism can have unfavorable effects in several biological processes, such as apoptosis, cell proliferation, growth, survival, stress response, angiogenesis, chemoresistance, invasion, and migration. Therefore, due to these dismal statistics, it is crucial to develop beneficial therapeutic strategies based on an improved understanding of the biology of both miRs and metabolic mediators. This review focuses on miR-mediated pathways and therapeutic resistance mechanisms in PDAC and evaluates the impact of metabolic alterations in the progression of PDAC.

Age-Related Pathways in Cardiac Regeneration: A Role for lncRNAs?

Aging imposes a barrier for tissue regeneration. In the heart, aging leads to a severe rearrangement of the cardiac structure and function and to a subsequent increased risk of heart failure. An intricate network of distinct pathways contributes to age-related alterations during healthy heart aging and account for a higher susceptibility of heart disease. Our understanding of the systemic aging process has already led to the design of anti-aging strategies or to the adoption of protective interventions. Nevertheless, our understanding of the molecular determinants operating during cardiac aging or repair remains limited. Here, we will summarize the molecular and physiological alterations that occur during aging of the heart, highlighting the potential role for long non-coding RNAs (lncRNAs) as novel and valuable targets in cardiac regeneration/repair.

Non-coding RNA biomarkers in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, which is usually diagnosed at an advanced stage. The late disease diagnosis, the limited availability of effective therapeutic interventions and lack of robust diagnostic biomarkers, are some of the primary reasons for the dismal 5-year survival rates (∼8%) in patients with PDAC. The pancreatic cancer develops through accumulation of a series of genomic and epigenomic alterations which lead to the transformation of normal pancreatic epithelium into an invasive carcinoma - a process that can take up to 15-20 years to develop, from the occurrence of first initiating mutational event. These facts highlight a unique window of opportunity for the earlier detection of PDAC, which could allow timely disease interception and improvement in the overall survival outcomes in patients suffering from this fatal malignancy. Non-coding RNAs (ncRNAs) have been recognized to play a central role in PDAC pathogenesis and are emerging as attractive candidates for biomarker development in various cancers, including PDAC. More specifically, the ncRNAs play a pivotal role in PDAC biology as they affect tumor growth, migration, and invasion by regulating cellular processes including cell cycle, apoptosis, and epithelial-mesenchymal transition. In this review, we focus on three types of well-established ncRNAs - microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) - and discuss their potential as diagnostic, prognostic and predictive biomarkers in PDAC.

Long non-coding RNA SNHG6 increases JAK2 expression by targeting the miR-181 family to promote colorectal cancer cell proliferation

BACKGROUND

Long non-coding RNA (lncRNA) small nucleolar RNA host gene 6 (SNHG6) exerts a regulatory role in cancer biology, although its detailed functions and mechanisms in colorectal cancer (CRC) still remain unclear.

METHODS

A quantitative reverse transcriptase-polymerase chain reaction was implemented to investigate the expression of SNHG6, miR-181 family and Janus kinase 2 (JAK2) in CRC tissues and cell lines. The proliferation of CRC cells was detected by a cell counting kit-8 assay, and the apoptosis of CRC cells was determined by flow cytometry analysis. The interaction of the miR-181 family with SNHG6 or with the 3'-untranslated region of JAK2 was validated by the luciferase reporter gene method. The effects of SNHG6 and the miR-181 family on JAK2 expression were analyzed by western blotting.

RESULTS

SNHG6 was significantly up-regulated in CRC samples. The knockdown of SNHG6 reduced the proliferation of CRC cells and promoted the apoptosis, whereas the over-expression of SNHG6 had the opposite effect. SNHG6 could bind with all the four members of the miR-181 family, and expression in miR-181 family members was significantly down-regulated in CRC samples. SNHG6 expression was negatively correlated with the miR-181 family member expression in CRC samples. Moreover, over-expressed SNHG6 significantly counteracted the inhibitory effect of miR-181 mimics on CRC cell proliferation, as well as the promoting effect on apoptosis. Furthermore, SNHG6 over-expression and knockdown can promote and inhibit JAK2 expression, respectively, and miR-181 family member function is opposite to that of SNHG6 by repressing JAK2.

CONCLUSIONS

SNHG6 can exert a cancer-promoting effect in CRC by targeting miR-181 family members and up-regulating JAK2.

Non-coding RNAs: emerging players in cardiomyocyte proliferation and cardiac regeneration

Soon after birth, the regenerative capacity of the mammalian heart is lost, cardiomyocytes withdraw from the cell cycle and demonstrate a minimal proliferation rate. Despite improved treatment and reperfusion strategies, the uncompensated cardiomyocyte loss during injury and disease results in cardiac remodeling and subsequent heart failure. The promising field of regenerative medicine aims to restore both the structure and function of damaged tissue through modulation of cellular processes and regulatory mechanisms involved in cardiac cell cycle arrest to boost cardiomyocyte proliferation. Non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) are functional RNA molecules with no protein-coding function that have been reported to engage in cardiac regeneration and repair. In this review, we summarize the current understanding of both the biological functions and molecular mechanisms of ncRNAs involved in cardiomyocyte proliferation. Furthermore, we discuss their impact on the structure and contractile function of the heart in health and disease and their application for therapeutic interventions.

The Multiple Roles of Hepatitis B Virus X Protein (HBx) Dysregulated MicroRNA in Hepatitis B Virus-Associated Hepatocellular Carcinoma (HBV-HCC) and Immune Pathways

Currently, the treatment of hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC) [HBV-HCC] relies on blunt tools that are unable to offer effective therapy for later stage pathogenesis. The potential of miRNA to treat HBV-HCC offer a more targeted approach to managing this lethal carcinoma; however, the complexity of miRNA as an ancillary regulator of the immune system remains poorly understood. This review examines the overlapping roles of HBx-dysregulated miRNA in HBV-HCC and immune pathways and seeks to demonstrate that specific miRNA response in immune cells is not independent of their expression in hepatocytes. This interplay between the two pathways may provide us with the possibility of using candidate miRNA to manipulate this interaction as a potential therapeutic option.

Chrysophanol protects PC12 cells against oxygen glucose deprivation-evoked injury by up-regulating miR-216a

BACKGROUND

Cerebral stroke refers to an acute onset of neurological deficit syndrome. In this research, we attempted to probe into the underlying mechanisms by which chrysophanol (CP) performed its regulatory roles in cerebral stroke. Methods OGD inducement was conducted in PC12 cells to construct a cerebral stroke model. Subsequently, CCK-8 assay, western blot, flow cytometry were utilized to determine cell viability, proliferation, and apoptosis, respectively. qRT-PCR was employed for detecting miR-216a expression level. Afterward, cell transfection was performed to alter miR-216a expression. Further, experiments were conducted to determine the expression of crucial factors participated in PI3 K/AKT and JAK2/STAT3 pathways for exploring the underlying mechanisms. Results OGD inducement suppressed cell viability, while promoted cell apoptosis. Besides, it enhanced the expression of proliferation-associated p53, p21, and apoptosis-associated Bax, and Cleaved-caspase-3, while suppressed the expression of Bcl-2. Furthermore, CHR exposure ameliorated the effects that OGD-evoked, and elevated the expression of miR-216a, as well as the expression of crucial factors participated in PI3 K/AKT and JAK2/STAT3 pathways. However, miR-216a silencing markedly reversed the effects triggered by CHR exposure. Conclusion CHR exposure relieved OGD-evoked PC12 cell damage by elevating miR-216a expression and thereby activating of PI3 K/AKT and JAK2/STAT3 pathways.

Overexpression of microRNA-216a-3p Accelerates the Inflammatory Response in Cardiomyocytes in Type 2 Diabetes Mellitus by Targeting IFN-α2

Background: Type 2 diabetes mellitus (T2DM) is a chronic, hyperglycemia-associated, metabolic disorder. Heart disease is a major complication of T2DM. The present study aimed to explore the effects of miR-216a-3p on cardiomyocyte proliferation, apoptosis, and inflammation in T2DM through the Toll-like receptor (TLR) pathway involving interferon-α2 (IFN-α2) mediation. Methods: T2DM was induced in rats by a high-fat diet, in combination with an intraperitoneal injection of low-dose streptozotocin. ELISAs were conducted to measure inflammatory-related factors in serum. Next, isolated cardiomyocytes were used in loss- and gain-of-function experiments, followed by MTT and flow cytometry assays, conducted to evaluate cell proliferation, cell cycle, and apoptosis. Results: Our results revealed an increase in the inflammatory response in T2DM rat models, accompanied by significantly increased expression of miR-216a-3p and TLR pathway-related genes. However, a decrease in the expression of IFN-α2 was observed. Moreover, the presence of an miR-216a-3p inhibitor and si-IFN-α2 increased the expression of TLR pathway-related genes and cell apoptosis, whereas cell proliferation was significantly decreased in the cardiomyocytes. Conclusion: We found that in T2DM, miR-216a-3p inhibited the proliferation and enhanced the apoptosis of cardiomyocytes and generated an inflammatory response through activation of the TLR pathway and targeting of IFN-α2.

Quercetin inhibits human microvascular endothelial cells viability, migration and tube-formation in vitro through restraining microRNA-216a

Background: Quercetin belongs to the flavonoids family, which has been proven to have extensive pharmacological effects. Nevertheless, the function of quercetin in peripheral arterial disease (PAD) has not yet been reported. In the research, we purposed to disclose the effectiveness of quercetin in the pathogenesis of PAD.Methods: HMEC-1 cells were cultivated in Matrigel for 24 h to observe the tube-formation. Detections of cell viability, migration and apoptosis were through implementing CCK-8, Transwell and flow cytometry methods. Western blot was utilised for measuring angiogenesis-, migration- and apoptosis-correlative factors. MiR-216a expression was examined via qRT-PCR, and its functions in HMEC-1 cells were uncovered after miR-216a mimic transfection. Assessment of JAK2/STAT3 and PI3K/AKT pathways was via implementing western blot.Results: HMEC-1 cells were spontaneously vascularised under Matrigel condition. Quercetin predominantly repressed cell viability, migration, VEGF expression and facilitated apoptosis in HMEC-1 cells. Additionally, suppression of miR-216a was discovered in HMEC-1 cells after quercetin stimulation, meanwhile miR-216a overexpression annulled the functions of quercetin in HMEC-1 cells. Besides, quercetin deactivated PI3K/AKT and JAK/STAT pathways through adjusting miR-216a.Conclusion: The above-mentioned consequences exhibited that quercetin suppressed HMEC-1 cell viability, migration and tube-formation through hindering JAK2/STAT3 and PI3K/AKT pathway via declination of miR-216a.

Micro-Ribonucleic Acid-216a Regulates Bovine Primary Muscle Cells Proliferation and Differentiation via Targeting SMAD Nuclear Interacting Protein-1 and Smad7

MicroRNAs (miRNAs), belonging to a class of evolutionarily conserved small noncoding RNA of ∼22 nucleotides, are widely involved in skeletal muscle growth and development by regulating gene expression at the post-transcriptional level. While the expression feature and underlying function of miR-216a in mammal skeletal muscle development, especially in cattle, remains to be further elucidated. The aim of this study was to investigate the function and mechanism of miR-216a during bovine primary muscle cells proliferation and differentiation. Herein, we found that the expression level of miR-216a both presented a downward trend during the proliferation and differentiation phases, which suggested that it might have a potential role in the development of bovine skeletal muscle. Functionally, during the cells proliferation phase, overexpression of miR-216a inhibited the expression of proliferation-related genes, reduced the cell proliferation status, and resulted in cells G1 phase arrest. In cells differentiation stages, overexpression of miR-216a suppressed myogenic maker genes mRNA, protein, and myotube formation. Mechanistically, we found that SNIP1 and smad7 were the directly targets of miR-216a in regulating bovine primary muscle cells proliferation and differentiation, respectively. Altogether, these findings suggested that miR-216a functions as a suppressive miRNA in development of bovine primary muscle cells via targeting SNIP1 and smad7.

MicroRNA in Pancreatic Cancer: From Biology to Therapeutic Potential

Pancreatic cancer is one of the most aggressive malignancies, accounting for more than 45,750 deaths annually in the U.S. alone. The aggressive nature and late diagnosis of pancreatic cancer, coupled with the limitations of existing chemotherapy, present the pressing need for the development of novel therapeutic strategies. Recent reports have demonstrated a critical role of microRNAs (miRNAs) in the initiation, progression, and metastasis of cancer. Furthermore, aberrant expressions of miRNAs have often been associated with the cause and consequence of pancreatic cancer, emphasizing the possible use of miRNAs in the effective management of pancreatic cancer patients. In this review, we provide a brief overview of miRNA biogenesis and its role in fundamental cellular process and miRNA studies in pancreatic cancer patients and animal models. Subsequent sections narrate the role of miRNA in, (i) cell cycle and proliferation; (ii) apoptosis; (iii) invasions and metastasis; and (iv) various cellular signaling pathways. We also describe the role of miRNA's in pancreatic cancer; (i) diagnosis; (ii) prognosis and (iii) therapeutic intervention. Conclusion section describes the gist of review with future directions.

Prolactin Promotes Fibrosis and Pancreatic Cancer Progression

Pancreatic ductal adenocarcinoma (PDAC) is associated with significant fibrosis. Recent findings have highlighted the profibrotic activity of tissue-resident macrophages in the pancreatic cancer microenvironment. Here, we show that neoplastic pancreatic epithelium, as well as a subset of tissue-resident macrophages, expresses the prolactin-receptor (PRLR). High mobility group box 1-induced prolactin expression in the pancreas maintained FAK1 and STAT3 phosphorylation within the epithelium and stroma. Gain-of-function and loss-of-function experiments demonstrated the essential role of prolactin in promoting collagen deposition and fibrosis. Finally, the signaling cascade downstream of prolactin/PRLR activated STAT3 rather than STAT5 in PDAC. These findings suggest that targeting prolactin together with IL6, a known major activator of STAT3, could represent a novel therapeutic strategy for treating pancreatic cancer. SIGNIFICANCE: Prolactin is a key factor in the cross-talk between the stroma and neoplastic epithelium, functioning to promote fibrosis and PDAC progression.

Knockout of Acinar Enriched microRNAs in Mice Promote Duct Formation But Not Pancreatic Cancer

The pancreatic acinar-enriched miR-216a, miR-216b and miR-217 are encoded within the miR217HG. These miRNAs have been purported to play a tumor suppressive role as their expression is reduced in both human and mouse pancreatic ductal adenocarcinoma (PDAC). To examine this possibility, we generated individual, germline knockout (KO) mice of miR-216a, miR-216b or miR-217. Unlike our previous study showing germline deletion of the miR217HG was embryonic lethal, CRISPR-Cas9 deleted portions of the 5' seed region of the miRNAs produced live births. To investigate possible phenotypes during pancreatic acinar ductal metaplasia (ADM), pancreatic acini from wild type and KO mice were plated on collagen and allowed to transdifferentiate over 4 days. Acini from each of the three miRNA KO mice produced greater numbers of ducts compared to controls. Evaluation of the gene expression during in vitro ADM demonstrated an increase in Krt19 and a reduction in acinar genes (Carboxypeptidase A1, Amylase2a) on day 4 of the transdifferentiation. Recovery was delayed for the miR-216a and miR-216b KOs following caerulein-induced acute pancreatitis. Also predominate in the caerulein treated miR-216a and miR-216b KO mice was the presence of pancreatic duct glands (PDGs). To further establish a phenotype, miRNA KO mice were crossed with EL-KRASG12D (EK) mice and followed up to 13 months of age. While all mice developed severe dysplasia and cystic papillary neoplasms, there existed no apparent phenotypic difference in the miRNA KO/EK mice compared to EK mice. Our data does not support a tumor suppressor role for miR-216a, miR-216b or miR-217 in PDAC and emphasizes the need for phenotypic evaluation of miRNAs in complex in vivo models beyond that performed using cell culture.

miR‑216a exacerbates TGF‑β‑induced myofibroblast transdifferentiation via PTEN/AKT signaling

Myofibroblast transdifferentiation is an important feature of cardiac fibrosis. Previous studies have indicated that microRNA‑216a (miR‑216a) is upregulated in response to transforming growth factor‑β (TGF‑β) in kidney cells and can activate Smad3; however, its role in myofibroblast transdifferentiation remains unclear. The present study aimed to investigate the role of miR‑216a in TGF‑β‑induced myofibroblast transdifferentiation, and to determine the underlying mechanisms. Adult mouse cardiac fibroblasts were treated with TGF‑β to induce myofibroblast transdifferentiation. An antagomir and agomir of miR‑216a were used to inhibit or overexpress miR‑216a in cardiac fibroblasts, respectively. Myofibroblast transdifferentiation was evaluated based on the levels of fibrotic markers and α‑smooth muscle actin expression. The miR‑216a antagomir attenuated, whereas the miR‑216a agomir promoted TGF‑β‑induced myofibroblast transdifferentiation. Mechanistically, miR‑216a accelerated myofibroblast transdifferentiation via the AKT/glycogen synthase kinase 3β signaling pathway, independent of the canonical Smad3 pathway. In addition, it was observed that miR‑216a activated AKT via the downregulation of PTEN. In conclusion, miR‑216a was involved in the regulation of TGF‑β‑induced myofibroblast transdifferentiation, suggesting that targeting miR‑216a may aid in developing effective interventions for the treatment of cardiac fibrosis.

MicroRNA profiling of pancreatic ductal adenocarcinoma (PDAC) reveals signature expression related to lymph node metastasis

Lymph node (LN) metastasis occurs frequently in pancreatic ductal adenocarcinoma (PDAC), representing an advanced disease stage and independently predicting patient survival. Current nodal staging is inadequate preoperatively and even less so postoperatively, and molecular biomarkers are needed to improve prognostication and selection of therapy. Recent data have suggested important roles of miRNAs in PDAC tumorigenesis and progression. The aim of the present study was to identify miRNA expression signature for nodal spread in PDAC patients. Using PDAC human tissue specimens, we identified 39 miRNAs which were differently expressed in LN positive compared to LN negative PDAC samples. Of them, six miRNAs have been reported to play a role in cancer invasion and metastasis. A high versus low six- miRNA signature score was predictive of LN metastasis in the PDAC validation cohort. We demonstrated a similar expression pattern of four out of the six miRNAs in the plasma of PDAC patients. The results of our in-vitro studies revealed that miR-141 and miR-720 are involved in the process of epithelial to mesenchymal-transition in PDAC. These miRNAs significantly inhibited in vitro proliferation, migration and invasion of PDAC cells as evidence by gain- and loss- of function studies, specifically, via ZEB-1 and TWIST1 transcription factors, as well as through the activation of the MAP4K4/JNK signaling pathway.

Differentiation antagonizing non-protein coding RNA modulates the proliferation, migration, and angiogenesis of glioma cells by targeting the miR-216a/LGR5 axis and the PI3K/AKT signaling pathway

Purpose: DANCR plays an important role in various types of cancer. However, its role in gliomas remains unclear. In the present study, we aimed to investigate the mechanism underlying the role of DANCR in gliomas.

Methods: DANCR expression was measured by qRT-PCR, and expression of LGR5, PI3K, AKT, and phosphorylated AKT (p-AKT) was detected by western blotting. The combination of miR-216a and DANCR was quantified by Luciferase reporter assays. Proliferation, apoptosis and cell cycle, migration and invasion, and angiogenesis of glioma cells were measured by MTT, flow cytometry, Transwell, and Tube formation assays, respectively.

Results: DANCR expression was significantly higher in glioma cells than in normal human astrocytes. Silencing of DANCR inhibited proliferation, migration, invasion, and angiogenesis of glioma cells, promoted apoptosis, blocked the cell cycle at the G1/S transition, and reduced LGR5, PI3K, and p-AKT expression. We identified miR-216a as a direct target of DANCR. Silencing of DANCR in glioma cells increased miR-216a expression. Further, miR-216a suppression increased proliferation, migration, invasion, and angiogenesis and inhibited apoptosis of glioma cells transfected with DANCR-targeting siRNA. In addition, miR-216a suppression compromised inhibition of the G1/S transition caused by DANCR silencing. Furthermore, suppression of miR-216a increased accumulation of LGR5, PI3K, AKT, and p-AKT in glioma cells transfected with DANCR-targeting siRNA.

Conclusion: DANCR modulates growth and metastasis by targeting the miR-216a/LGR5 axis and PI3K/AKT signaling pathway.

Upregulation of miR-216a exerts neuroprotective effects against ischemic injury through negatively regulating JAK2/STAT3-involved apoptosis and inflammatory pathways

OBJECTIVE

Ischemic stroke remains a significant cause of death and disability in industrialized nations. Janus tyrosine kinase (JAK) and signal transducer and activator of transcription (STAT) of the JAK2/STAT3 pathway play important roles in the downstream signal pathway regulation of ischemic stroke-related inflammatory neuronal damage. Recently, microRNAs (miRNAs) have emerged as major regulators in cerebral ischemic injury; therefore, the authors aimed to investigate the underlying molecular mechanism between miRNAs and ischemic stroke, which may provide potential therapeutic targets for ischemic stroke.

METHODS

The JAK2- and JAK3-related miRNA (miR-135, miR-216a, and miR-433) expression levels were detected by real-time quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and Western blot analysis in both oxygen-glucose deprivation (OGD)-treated primary cultured neuronal cells and mouse brain with middle cerebral artery occlusion (MCAO)-induced ischemic stroke. The miR-135, miR-216a, and miR-433 were determined by bioinformatics analysis that may target JAK2, and miR-216a was further confirmed by 3' untranslated region (3'UTR) dual-luciferase assay. The study further detected cell apoptosis, the level of lactate dehydrogenase, and inflammatory mediators (inducible nitric oxide synthase [iNOS], matrix metalloproteinase-9 [MMP-9], tumor necrosis factor-α [TNF-α], and interleukin-1β [IL-1β]) after cells were transfected with miR-NC (miRNA negative control) or miR-216a mimics and subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) damage with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, annexin V-FITC/PI, Western blots, and enzyme-linked immunosorbent assay detection. Furthermore, neurological deficit detection and neurological behavior grading were performed to determine the infarction area and neurological deficits.

RESULTS

JAK2 showed its highest level while miR-216a showed its lowest level at day 1 after ischemic reperfusion. However, miR-135 and miR-433 had no obvious change during the process. The luciferase assay data further confirmed that miR-216a can directly target the 3'UTR of JAK2, and overexpression of miR-216a repressed JAK2 protein levels in OGD/R-treated neuronal cells as well as in the MCAO model ischemic region. In addition, overexpression of miR-216a mitigated cell apoptosis both in vitro and in vivo, which was consistent with the effect of knockdown of JAK2. Furthermore, the study found that miR-216a obviously inhibited the inflammatory mediators after OGD/R, including inflammatory enzymes (iNOS and MMP-9) and cytokines (TNF-α and IL-1β). Upregulating miR-216a levels reduced ischemic infarction and improved neurological deficit.

CONCLUSIONS

These findings suggest that upregulation of miR-216a, which targets JAK2, could induce neuroprotection against ischemic injury in vitro and in vivo, which provides a potential therapeutic target for ischemic stroke.

Long noncoding RNA myocardial infarction-associated transcript regulated the pancreatic stellate cell activation to promote the fibrosis process of chronic pancreatitis

BACKGROUND

Long noncoding RNAs (lncRNAs) play crucial roles in fibrosis process. In our previous RNA-seq study, we found that lncRNA myocardial infarction-associated transcript (MIAT) was differentially expressed in pancreatic tissues of chronic pancreatitis (CP) patients. However, the function of MIAT in CP remains unknown. This study was aimed to investigate the function and underlying mechanism of MIAT in pancreatic fibrosis.

MATERIALS AND METHODS

The expression levels of MIAT, miR-216a-3p, cyclooxygenase 2 (COX-2), α-smooth muscle actin (α-SMA), and collagen I were estimated by Western blot analysis and qualitative reverse transcription polymerase chain reaction. The relationships between miR-216a-3p, MIAT, and COX-2 were confirmed by luciferase reporter assay. The proliferation of human pancreatic stellate cells (HPaSteCs) was detected by cell counting kit-8 assay.

RESULTS

We found that MIAT, along with the levels of fibrosis-related proteins α-SMA and collagen I, as well as COX-2 were upregulated, while miR-216a-3p was downregulated in transforming growth factor (TGF)-β1-stimulated HPaSteCs. Mechanistically, MIAT acted as a molecular sponge for miR-216a-3p. Furthermore, we identified COX-2 as a direct target of miR-126a-3p. Additionally, MIAT overturned the inhibitory effect of miR-216a-3p overexpression and COX-2 knockdown on the activation and proliferation of HPaSteCs.

CONCLUSION

Our study provided mechanistic insights into a critical role for MIAT as a miRNA sponge in CP.

A long noncoding RNA NR_045363 controls cardiomyocyte proliferation and cardiac repair

Long noncoding RNAs (lncRNAs) play important roles in the regulation of genes involved in cell proliferation. We have previously sought to more globally understand the differences of lncRNA expression between human fetal heart and adult heart to identify some functional lncRNAs which involve in the process of heart repair. We found that a highly conserved long noncoding RNA NR_045363 was mainly expressed in cardiomyocytes and rarely in non-cardiomyocytes. NR_045363 overexpression in 7-day-old mice heart could improve cardiac function and stimulate cardiomyocyte proliferation after myocardial infarction. Furthermore, NR_045363 knockdown inhibited proliferation of primary embryonic cardiomyocytes, while NR_045363 overexpression enhanced DNA synthesis and cytokinesis in neonatal cardiomyocytes in vitro. Mechanistic analysis revealed that NR_045363 promoted cardiomyocyte proliferation through interaction with miR-216a, which regulated the JAK2-STAT3 pathway. Our results showed that NR_045363 is a potent lncRNA modulator essential for cardiomyocyte proliferation.

LncRNA DANCR Promotes Lung Cancer by Sequestering miR-216a

BACKGROUND

Long noncoding RNAs (lncRNAs) are a new class of cancer regulators. Here, we aimed to investigate the diagnostic and therapeutic values of an lncRNA, differentiation antagonizing noncoding RNA (DANCR), in lung cancer.

METHODS

Real-time polymerase chain reaction was used to compare DANCR levels in normal and cancerous lung tissues as well as lung cancer cells. Lentiviral transduction was used to induce DANCR overexpression or silencing in vitro, followed by monitoring cell proliferation, colony formation, and changes in microRNA-216a (miR-216a) expression. DANCR-specific small hairpin RNA transduction was used to establish cells with stable DANCR knockdown, and silenced cells were used to initiate lung tumor xenografts, followed by monitoring tumor growth.

RESULTS

DANCR upregulation was seen in lung cancer, particularly in high-grade lung cancer tissues and aggressive cancer cells. Ectopic DANCR expression induced lung cancer cell proliferation and colony formation, whereas DANCR silencing induced opposing effects. The miR-216a level in cancer cells was negatively correlated with DANCR expression. The DANCR knockdown reduced the growth of tumor xenografts in vivo.

CONCLUSION

DANCR upregulation is a potential indicator of aggressive lung cancer. Silencing of DANCR has great potential as a potent therapeutic strategy in lung cancer.

MiR-216a inhibits proliferation and promotes apoptosis of human airway smooth muscle cells by targeting JAK2

Objective: Accumulating evidence suggests that aberrantly expressed microRNAs in airway smooth muscle (ASM) cells could change airway remodeling during the development of asthma. However, the underlying functions of microRNAs in ASM cell proliferation and apoptosis need to be further elucidated. Methods: By using RT-qPCR, miR-216a expression level was examined in the asthmatic patients and non-asthmatic individuals. Cell proliferation assay and flow cytometry analysis were used in ASM cells in which miR-216a was an abnormal expression. MiR-216a predicted to target gene was explored by bioinformatic software, and further analyzed by Western blotting and luciferase reporter assay. Results: Our results demonstrated that miR-216a levels were considerably lower in the ASM cells of asthmatic patients than in those of non-asthmatic individuals. Further study verified that the overexpression of miR-216a markedly suppressed cell proliferation and promoted cell apoptosis, whereas the knockdown of miR-216a had opposite effects in ASM cells. In addition, luciferase reporter assays and Western blotting identified that JAK2 was the direct functional target of miR-216a, and the ectopic expression of JAK2 partially rescued the inhibitory effect of miR-216a in ASM cells. Conclusions: The above data indicate that miR-216a may function as a key regulator of airway remodeling by targeting JAK2, thus suggesting the potential role of miR-216a in the pathogenesis of asthma.

STAT3 regulated miR-216a promotes ovarian cancer proliferation and cisplatin resistance

Cisplatin is the first-line treatment for ovarian cancer. However, the clinical outcome of cisplatin treatment in ovarian cancer is hindered by cancer resistance. Here we aim to explore the role and mechanism of miR-216a in the cisplatin resistance of ovarian cancer. The effects of miR-216a overexpression and inhibition on ovarian cell proliferation, colony formation, and cisplatin resistance were investigated by MTT assay and soft agar colony formation assay. Bioinformatics analyses using TargetScan and rVista, qPCR, and luciferase assay were also used to explore and verify downstream effectors and regulators of miR-216a. Proliferation, colony formation, and cisplatin resistance of ovarian cancer cells are promoted by miR-216a overexpression but inhibited by miR-216a inhibition. PTEN is a direct target of miR-216a and PTEN expression antagonizes the tumor-promoting function of miR-216a. STAT3 is a regulator of miR-216a, and PTEN is also regulated by STAT3. miR-216a up-regulation is associated with cisplatin resistance in ovarian cancer and this effect is mediated by PTEN. STAT3 is a regulator of miR-216a. Strategies that inhibit miR-216a is a potential strategy for overcoming the cisplatin resistance in ovarian cancer.

Genome‑scale analysis to identify potential prognostic microRNA biomarkers for predicting overall survival in patients with colon adenocarcinoma

The aim of the present study was to identify potential prognostic microRNA (miRNA) biomarkers for colon adenocarcinoma (COAD) prognostic prediction using the dataset of The Cancer Genome Atlas (TCGA). The genome‑wide miRNA sequencing dataset and corresponding COAD clinical information were downloaded from TCGA. Prognosis‑related miRNA screening was performed by genome‑wide multivariable Cox regression analysis and used for prognostic signature construction. Ten miRNAs (hsa‑mir‑891a, hsa‑mir‑6854, hsa‑mir‑216a, hsa‑mir‑378d‑1, hsa‑mir‑92a‑1, hsa‑mir‑4709, hsa‑mir‑92a‑2, hsa‑mir‑210, hsa‑mir‑940 and hsa‑mir‑887) were identified as prognostic miRNAs and used for further prognostic signature construction. The 10‑miRNA prognostic signature showed good performance in prognosis prediction (adjusted P<0.0001; adjusted hazard ratio, 4.580; 95% confidence interval, 2.783‑7.538). In the time‑dependent receiver operating characteristic analysis, the area under the curve was 0.735, 0.788, 0.806, 0.806, 0.775 and 0.900 for 1‑, 2‑, 3‑, 4‑, 5‑ and 10‑year COAD overall survival prediction, respectively. Comprehensive survival analysis suggested that the 10‑miRNA prognostic signature is an independent prognostic factor in COAD, with a better performance in COAD overall survival prediction than other traditional clinical parameters. Functional enrichment indicated that the corresponding target genes were significantly enriched in multiple biological processes and pathways, including regulation of cell proliferation, cell cycle, cell growth, and Wnt and transforming growth factor‑β signaling pathways. In conclusion, our present study identified a 10‑miRNA expression signature that may serve as a potential prognostic biomarker in COAD patients.

MicroRNA-216a Inhibits NF-κB-Mediated Inflammatory Cytokine Production in Teleost Fish by Modulating p65

Inflammation is the host self-protection mechanism to eliminate pathogen invasion. The excessive inflammatory response can result in uncontrolled inflammation, autoimmune diseases, or pathogen dissemination. Recent studies have widely shown that microRNAs (miRNAs) contribute to the regulation of inflammation in mammals by repressing gene expression at the posttranscriptional level. However, the miRNA-mediated mechanism in the inflammatory response in fish remains hazy. In the present study, the regulatory mechanism of the miR-216a-mediated inflammatory response in teleost fish was addressed. We found that the expression of miR-216a could be significantly upregulated in the miiuy croaker after challenge with Vibrio anguillarum and lipopolysaccharide. Bioinformatics predictions demonstrated a potential binding site of miR-216a in the 3' untranslated region of the p65 gene, and the result was further confirmed by luciferase assay. Moreover, both the mRNA and protein levels of p65 in macrophages were downregulated by miR-216a. Deletion mutant analysis of the miR-216a promoter showed that the Ap1 and Sp1 transcription factor binding sites are indispensable for the transcription of miR-216a. Further study revealed that overexpression of miR-216a suppresses inflammatory cytokine expression and negatively regulates NF-κB signaling, which inhibit an excessive inflammatory response. The collective results indicate that miR-216a plays a role as a negative regulator involved in modulating the bacterium-induced inflammatory response.

MiR-216a-5p/Hexokinase 2 axis regulates uveal melanoma growth through modulation of Warburg effect

Hexokinase-2 (HK2), the initial as well as the rate-limiting step in glycolysis, is overexpressed in many human cancers, and correlates with poor clinical outcomes. Aerobic glycolysis is a hallmark of cancer, and drugs targeting its enzymes, including HK2, are being developed. However, the mechanisms of HK2 inhibition and the physiological significance of the HK2 inhibitors in cancer cells are rarely reported. Here, we show that microRNA-216a-5p (miR-216a-5p) inhibits HK2 expression by directly targeting its 3'-UTR in uveal melanoma cells. Through inhibition of HK2, miR-216a-5p dampens glycolysis by reducing HK activity, glucose uptake, lactate production, ATP generation, extracellular acidification rate (ECAR), and increasing oxygen consumption rate (OCR) in uveal melanoma cells. Importantly, glycolysis regulated by miR-216a-5p is critical for its regulating uveal melanoma tumor growth both in vitro and in vivo. miR-216a-5p expression is negatively correlated with HK2 expression and predicts better outcome in uveal melanoma patients. Our findings provide clues regarding the role of miR-216a-5p as a tumor suppressor in uveal melanoma through the inhibition of HK2. Targeting HK2 through miR-216a-5p could be a promising therapeutic strategy in uveal melanoma.

Personalized RNA Medicine for Pancreatic Cancer

Purpose: Since drug responses vary between patients, it is crucial to develop pre-clinical or co-clinical strategies that forecast patient response. In this study, we tested whether RNA-based therapeutics were suitable for personalized medicine by using patient-derived-organoid (PDO) and patient-derived-xenograft (PDX) models.Experimental Design: We performed microRNA (miRNA) profiling of PDX samples to determine the status of miRNA deregulation in individual pancreatic ductal adenocarcinoma (PDAC) patients. To deliver personalized RNA-based-therapy targeting oncogenic miRNAs that form part of this common PDAC miRNA over-expression signature, we packaged antimiR oligonucleotides against one of these miRNAs in tumor-penetrating nanocomplexes (TPN) targeting cell surface proteins on PDAC tumors.Results: As a validation for our pre-clinical strategy, the therapeutic potential of one of our nano-drugs, TPN-21, was first shown to decrease tumor cell growth and survival in PDO avatars for individual patients, then in their PDX avatars.Conclusions: This general approach appears suitable for co-clinical validation of personalized RNA medicine and paves the way to prospectively identify patients with eligible miRNA profiles for personalized RNA-based therapy. Clin Cancer Res; 24(7); 1734-47. ©2018 AACR.

miR-216a-5p acts as an oncogene in renal cell carcinoma

MiR-216a-5p has been acknowledged as an oncogene and is known to be involved in the progression and metastasis of numerous cancer subtypes. However, the potential role of miR-216a-5p in renal cell carcinoma (RCC) remains to be elucidated. In the present study, reverse transcription-quantitative polymerase chain reaction was performed to detect the expression levels of miR-216a-5p in RCC tissues. Cell counting kit-8, MTT, wound scratch, Transwell and flow cytometric assays were performed to establish the biological functions of miR-216a-5p in RCC. Functional experiments demonstrated that the expression of miR-216a-5p was upregulated in RCC (P<0.05) and miR-216a-5p mimics promoted cellular proliferation, viability and motility, and suppressed apoptosis. Conversely, miR-216a-5p inhibitor suppressed cellular proliferation, viability, motility and induced apoptosis. Based on these findings, it was concluded that miR-216a-5p may function as an oncogene in RCC. MiR-216a-5p target genes need to be explored and the potential of miR-216a-5p to be used as a diagnostic or a prognostic biomarker for RCC needs to be validated by future research.

miR-216a inhibits osteosarcoma cell proliferation, invasion and metastasis by targeting CDK14

Osteosarcoma (OS) has emerged as the most common primary musculoskeletal malignant tumour affecting children and young adults. Cyclin-dependent kinases (CDKs) are closely associated with gene regulation in tumour biology. Accumulating evidence indicates that the aberrant function of CDK14 is involved in a broad spectrum of diseases and is associated with clinical outcomes. MicroRNAs (miRNAs) are crucial epigenetic regulators in the development of OS. However, the essential role of CDK14 and the molecular mechanisms by which miRNAs regulate CDK14 in the oncogenesis and progression of OS have not been fully elucidated. Here we found that CDK14 expression was closely associated with poor prognosis and overall survival of OS patients. Using dual-luciferase reporter assays, we also found that miR-216a inhibits CDK14 expression by binding to the 3′-untranslated region of CDK14. Overexpression of miR-216a significantly suppressed cell proliferation, migration and invasion in vivo and in vitro by inhibiting CDK14 production. Overexpression of CDK14 in the miR-216a-transfected OS cells effectively rescued the suppression of cell proliferation, migration and invasion caused by miR-216a. In addition, Kaplan–Meier analysis indicated that miR-216a expression predicted favourable clinical outcomes for OS patients. Moreover, miR-216a expression was downregulated in OS patients and was negatively associated with CDK14 expression. Overall, these data highlight the role of the miR-216a/CDK14 axis as a novel pleiotropic modulator and demonstrate the associated molecular mechanisms, thus suggesting the intriguing possibility that miR-216a activation and CDK14 inhibition may be novel and attractive therapeutic strategies for treating OS patients.

The Regulation of Notch Signaling in Retinal Development and Regeneration

Purpose of review

Notch signaling is an important component of retinal progenitor cell maintenance and MG specification during development, and its manipulation may be critical for allowing MG to re-enter the cell cycle and regenerate neurons in adults. In mammals, MG respond to retinal injury by undergoing a gliotic response rather than a regenerative one. Understanding the complexities of Notch signaling may allow for strategies that enhance regeneration over gliosis.

Recent findings

Notch signaling is regulated at multiple levels, and is interdependent with various other signaling pathways in both the receptor and ligand expressing cells. The precise spatial and temporal patterning of Notch components is necessary for proper retinal development. Regenerative species undergo a dynamic regulation of Notch signaling in MG upon injury, whereas non-regenerative species fail to productively regulate Notch.

Summary

Notch signaling is malleable, such that the altered composition of growth and transcription factors in the developing and mature retinas result in different Notch mediated responses. Successful regeneration will require the manipulation of the retinal environment to foster a dynamic rather than static regulation of Notch signaling in concert with other reprogramming and differentiation factors.

MicroRNA-216a inhibits the metastasis of gastric cancer cells by targeting JAK2/STAT3-mediated EMT process

MicroRNAs (miRNAs), a group of small, non-protein coding, endogenous RNAs, play critical roles in the tumorigenesis and progression of human cancer. miR-216a has recently been reported to play an oncogenic role in human cancer. While, the expression of miR-216a, its biological function and underlying molecular mechanisms in gastric cancer (GC) are largely unknown. In this study, we revealed that miR-216a was underexpressed in GC tissues compared to matched noncancerous tissues. Decreased levels of miR-216a were confirmed in GC cell lines compared with a normal gastric epithelium cell line. miR-216a underexpression was associated with malignant prognostic features including lymph node metastasis, venous infiltration, invasive depth and advanced TNM stage. GC patients with low miR-216a level showed an obvious shorter overall survival. miR-216a overexpression restrained migration and invasion of MGC-803 cells, while its knockdown exerted opposite effects on metastatic behaviors of SGC-7901 cells. In vivo experiments found that miR-216a restoration reduced metastatic nodes of GC cells in nude mice liver. miR-216a notably suppressed epithelial-mesenchymal transition (EMT) of GC cells. Janus kinase 2 (JAK2) was recognized as a direct target and downstream mediator of miR-216a in GC cells. Interestingly, JAK2/signal transducer and activator of transcription 3 (STAT3) pathway was prominently inactivated by miR-216a and probably mediated the role of miR-216a in the regulation of migration, invasion and EMT process of GC cells. In conclusion, these data suggest that miR-216a functions as a tumor suppressive miRNA in the development of GC possibly by targeting JAK2/STAT3-mediated EMT.

miR-216a-3p Inhibits the Proliferation, Migration, and Invasion of Human Gastric Cancer Cells via Targeting RUNX1 and Activating the NF-κB Signaling Pathway

This work aims to elucidate the effects and the potential underlying mechanisms of microRNA-216a-3p (miR-216a-3p) on the proliferation, migration, and invasion of gastric cancer (GC) cells. In this study, we revealed that the expression of miR-216a-3p was significantly elevated in GC tissues and cell lines. The different expression level of miR-216a-3p was firmly correlated with clinicopathological characteristics of GC patients. We next demonstrated that upregulation of miR-216a-3p could dramatically promote the ability of proliferation, migration, and invasion of GC cells using a series of experiments, whereas downregulation essentially inhibited these properties. Additionally, through bioinformatics analysis and biological approaches, we confirmed that runt-related transcription factor 1 (RUNX1) was a direct target of miR-216a-3p, and overexpression of RUNX1 could reverse the potential effect of miR-216a-3p on GC cells. Furthermore, mechanistic investigation using Western blot analysis showed that downregulation of RUNX1 by miR-216a-3p could stimulate the activation of NF-κB signaling pathway. In summary, this work proved that miR-216a-3p can promote GC cell proliferation, migration, and invasion via targeting RUNX1 and activating the NF-κB signaling pathway. Therefore, miR-216a-3p/RUNX1 could be a possible molecular target for innovative therapeutic agents against GC.

The microRNA expression signature of pancreatic ductal adenocarcinoma by RNA sequencing: anti-tumour functions of the microRNA-216 cluster

We analysed the RNA sequence-based microRNA (miRNA) signature of pancreatic ductal adenocarcinoma (PDAC). Aberrantly expressed miRNAs were successfully identified in this signature. Using the PDAC signature, we focused on 4 clustered miRNAs, miR-216a-5p, miR-216a-3p, miR-216b-5p and miR-216b-3p on human chromosome 2p16.1. All members of the miR-216 cluster were significantly reduced in PDAC specimens. Ectopic expression of these miRNAs suppressed cancer cell aggressiveness, suggesting miR-216 cluster as anti-tumour miRNAs in PDAC cells. The impact of miR-216b-3p (passenger strand of pre-miR-216b) on cancer cells is still ambiguous. Forkhead box Q1 (FOXQ1) was directly regulated by miR-216b-3p and overexpression of FOXQ1 was confirmed in clinical specimens. High expression of FOXQ1 predicted a shorter survival of patients with PDAC by Kaplan–Meier analysis. Loss-of-function assays showed that cancer cell migration and invasion activities were significantly reduced by siFOXQ1 transfectants. We investigated pathways downstream from FOXQ1 by using genome-wide gene expression analysis. Identification of the miR-216-3p/FOXQ1-mediated network in PDAC should enhance understanding of PDAC aggressiveness at the molecular level.

MicroRNA-452 suppresses pancreatic cancer migration and invasion by directly targeting B-cell-specific Moloney murine leukemia virus insertion site 1

Pancreatic cancer, one of the most common cancers globally, is the fourth most common cause of cancer-associated mortality in the USA. The 5-year relative survival rate for patients with pancreatic cancer is ~5% and the median survival time is only 6 months. The poor prognosis is mainly due to early and aggressive local invasion and metastasis, as well as dissemination of the pancreatic cancer cells. The present study demonstrated that microRNA-452 (miR-452) was markedly downregulated in pancreatic cancer tissues, particularly in metastatic tumors and pancreatic cancer cell lines. Overexpression of miR-452 significantly inhibited migration and invasion in pancreatic cancer cells. In addition, the molecular mechanism underlying the inhibitory functions of miR-452 in pancreatic cancer was also investigated. The results indicated that B-cell-specific Moloney murine leukemia virus insertion site 1 (BMI1) was a direct target gene of miR-452 in pancreatic cancer. Overexpression of miR-452 inhibited the migration and invasion of pancreatic cancer, at least partially by knockdown of BMI1 expression. The results provided novel insight with potential therapeutic applications for the treatment of metastatic pancreatic cancer.

Overexpression of MicroRNA-216a Suppresses Proliferation, Migration, and Invasion of Glioma Cells by Targeting Leucine-Rich Repeat-Containing G Protein-Coupled Receptor 5

Increasing studies have suggested that microRNAs (miRNAs) are involved in the development of gliomas. MicroRNA-216a has been reported to be a tumor-associated miRNA in many types of cancer, either as an oncogene or as a tumor suppressor. However, little is known about the function of miR-216a in gliomas. The present study was designed to explore the potential role of miR-216a in gliomas. We found that miR-216a was significantly decreased in glioma tissues and cell lines. Overexpression of miR-216a significantly suppressed the proliferation, migration, and invasion of glioma cells. Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) was identified as a target gene of miR-216a in glioma cells by bioinformatics analysis, dual-luciferase reporter assay, real-time quantitative polymerase chain reaction, and Western blot analysis. Moreover, miR-216a overexpression inhibited the Wnt/β-catenin signaling pathway. The restoration of LGR5 expression markedly reversed the antitumor effect of miR-216a in glioma cells. Taken together, these findings suggest a tumor suppressor role for miR-216a in gliomas, which inhibits glioma cell proliferation, migration, and invasion by targeting LGR5. Our study suggests that miR-216a may serve as a potential therapeutic target for future glioma treatment.

Down-regulation of KIAA1199/CEMIP by miR-216a suppresses tumor invasion and metastasis in colorectal cancer

Colorectal cancer is one of the major causes of death from cancer. Metastasis is the leading cause of treatment failure, in which cancer stem cells and circulating tumor cells play crucial roles. Identifying the involved metastatic biomarkers and clarifying the regulation mechanisms are of great importance for targeting tumor metastasis. In the current research, we discovered that KIAA1199, a cell-migration inducing protein, showed higher expression in CD44+ cancer cells from metastatic compared with the paired primary tissues, and was upregulated in colorectal cancer and positively correlated with numbers and mesenchymal phenotype of circulating tumor cells, and predicted shorter progress-free survival. Moreover, we indicated that down-regulation of KIAA1199 suppressed migration and invasion of colorectal cancer cells in vitro, and inhibited metastasis in vivo. Furthermore, we demonstrated that KIAA1199 was one of the direct and functional targets of miR-216a, and miR-216a overexpression led to decreased migration and invasion of colorectal cancer cells in vitro, and inhibited metastasis in vivo. Collectively, KIAA1199 plays a critical role in maintaining an aggressive phenotype of tumor cells, and suppression of KIAA1199-related motilities of tumor cells contributes to reduced tumor metastasis in colorectal cancer.

ZFP36L2 promotes cancer cell aggressiveness and is regulated by antitumor microRNA-375 in pancreatic ductal adenocarcinoma

Due to its aggressive nature, pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal and hard-to-treat malignancies. Recently developed targeted molecular strategies have contributed to remarkable improvements in the treatment of several cancers. However, such therapies have not been applied to PDAC. Therefore, new treatment options are needed for PDAC based on current genomic approaches. Expression of microRNA-375 (miR-375) was significantly reduced in miRNA expression signatures of several types of cancers, including PDAC. The aim of the present study was to investigate the functional roles of miR-375 in PDAC cells and to identify miR-375-regulated molecular networks involved in PDAC aggressiveness. The expression levels of miR-375 were markedly downregulated in PDAC clinical specimens and cell lines (PANC-1 and SW1990). Ectopic expression of miR-375 significantly suppressed cancer cell proliferation, migration and invasion. Our in silico and gene expression analyses and luciferase reporter assay showed that zinc finger protein 36 ring finger protein-like 2 (ZFP36L2) was a direct target of miR-375 in PDAC cells. Silencing ZFP36L2 inhibited cancer cell aggressiveness in PDAC cell lines, and overexpression of ZFP36L2 was confirmed in PDAC clinical specimens. Interestingly, Kaplan-Meier survival curves showed that high expression of ZFP36L2 predicted shorter survival in patients with PDAC. Moreover, we investigated the downstream molecular networks of the miR-375/ZFP36L2 axis in PDAC cells. Elucidation of tumor-suppressive miR-375-mediated PDAC molecular networks may provide new insights into the potential mechanisms of PDAC pathogenesis.