MicroRNA-199a-3p suppresses glioma cell proliferation by regulating the AKT/mTOR signaling pathway

Practical immunomodulatory landscape of glioblastoma multiforme (GBM) therapy

Glioblastoma multiforme (GBM) is the most common harmful high-grade brain tumor with high mortality and low survival rate. Importantly, besides routine diagnostic and therapeutic methods, modern and useful practical techniques are urgently needed for this serious malignancy. Correspondingly, the translational medicine focusing on genetic and epigenetic profiles of glioblastoma, as well as the immune framework and brain microenvironment, based on these challenging findings, indicates that key clinical interventions include immunotherapy, such as immunoassay, oncolytic viral therapy, and chimeric antigen receptor T (CAR T) cell therapy, which are of great importance in both diagnosis and therapy. Relatively, vaccine therapy reflects the untapped confidence to enhance GBM outcomes. Ongoing advances in immunotherapy, which utilizes different methods to regenerate or modify the resistant body for cancer therapy, have revealed serious results with many different problems and difficulties for patients. Safe checkpoint inhibitors, adoptive cellular treatment, cellular and peptide antibodies, and other innovations give researchers an endless cluster of instruments to plan profoundly in personalized medicine and the potential for combination techniques. In this way, antibodies that block immune checkpoints, particularly those that target the program death 1 (PD-1)/PD-1 (PD-L1) ligand pathway, have improved prognosis in a wide range of diseases. However, its use in combination with chemotherapy, radiation therapy, or monotherapy is ineffective in treating GBM. The purpose of this review is to provide an up-to-date overview of the translational elements concentrating on the immunotherapeutic field of GBM alongside describing the molecular mechanism involved in GBM and related signaling pathways, presenting both historical perspectives and future directions underlying basic and clinical practice.

miR-199a/b-3p inhibits HCC cell proliferation and invasion through a novel compensatory signaling pathway DJ-1\Ras\PI3K/AKT

Several studies have reported the effects of DJ-1 gene and miR-199a/b-3p on HCC development. However, whether miR-199a/b-3p regulates HCC progression through a novel compensatory signaling pathway involving DJ-1, Ras, and PI3K/AKT remains unknown. We used (TCGA, HPA, miRWalk and Target scan) databases, cancer and para-tissue HCC patients, dual-luciferase reporter gene analysis, proteomic imprinting, qPCR, cell proliferation, scratch, transport, and flow cytometry to detect the molecular mechanism of DJ-1 and miR-199a/b-3p co-expression in HCC cell lines. Bioinformatics analysis showed that DJ-1 was highly expressed in HCC ((P < 0.001) were closely associated with tumor stage (T), portal vein vascular invasion, OS, DSS, and PFI (P < 0.05); miR-199a/b-3p was lowly expressed in HCC (P < 0.001), which was the upstream regulator of DJ-1. Spearman coefficient r = -0.113, P = 0.031; Dual luciferase gene report verified the negative targeting relationship between them P< 0.001; Western blotting demonstrated that miR-199a/b-3p could inhibit the protein expression of DJ-1, Ras and AKT(P < 0.05); The results of CCK8, cell scratch, Transwell migration and flow cytometry showed that OE + DJ-1 increased the proliferation, migration and invasion ability of HepG2 cells, and decreased the apoptosis process, and the differences were statistically significant (P < 0.05), while miR-199a/b-3p had the opposite effect (P < 0.05).

MicroRNA-199a-3p suppresses the invasion and metastasis of nasopharyngeal carcinoma through SCD1/PTEN/AKT signaling pathway

MicroRNAs (miRs) are 18-25 nucleotides non-coding RNAs, which contribute to tumorigenesis. Previous studies have demonstrated that miR-199a-3p is dysregulated in human nasopharyngeal carcinoma (NPC), but its role in NPC progression still largely unknown. The current study aimed to determine the potential role of miR-199a-3p in NPC progression and the underlying mechanisms. In this study, miR-199a-3p was found to be prominently down-regulated in NPC tissues and cells. The cellular assay showed that transfection of miR-199a-3p markedly repressed the migration, invasion and induced epithelial-mesenchymal transition (EMT) in both 5-8F and CNE-2 cell lines. By dual-luciferase reporter, western blotting and gas chromatography assays, we found that SCD1 is not only highly expressed in NPC tissues and negatively associated with the prognosis of NPC patients but also can be apparently downregulated by miR-199a-3p in NPC cells, suggesting that SCD1 is a direct target gene of miR-199a-3p. Moreover, inhibition of miR-199a-3p expression activated PI3K/Akt signaling and up-regulated the expression of MMP-2. With tumor xenograft models in nude mice, we also showed that miR-199a-3p repressed tumor growth in vivo. Our study demonstrated that miR-199a-3p inhibited migration and invasion of NPC cells through downregulating SCD1 expression, thus providing a potential target for the treatment of NPC.

Comparison of Oncogenes, Tumor Suppressors, and MicroRNAs Between Schizophrenia and Glioma: The Balance of Power

The risk of cancer in schizophrenia has been controversial. Confounders of the issue are cigarette smoking in schizophrenia, and antiproliferative effects of antipsychotic medications. The author has previously suggested comparison of a specific cancer like glioma to schizophrenia might help determine a more accurate relationship between cancer and schizophrenia. To accomplish this goal, the author performed three comparisons of data; the first a comparison of conventional tumor suppressors and oncogenes between schizophrenia and cancer including glioma. This comparison determined schizophrenia has both tumor-suppressive and tumor-promoting characteristics. A second, larger comparison between brain-expressed microRNAs in schizophrenia with their expression in glioma was then performed. This identified a core carcinogenic group of miRNAs in schizophrenia offset by a larger group of tumor-suppressive miRNAs. This proposed "balance of power" between oncogenes and tumor suppressors could cause neuroinflammation. This was assessed by a third comparison between schizophrenia, glioma and inflammation in asbestos-related lung cancer and mesothelioma (ALRCM). This revealed that schizophrenia shares more oncogenic similarity to ALRCM than glioma.

miR-199a-3p promotes gastric cancer progression by promoting its stemness potential via DDR2 mediation

BACKGROUND

Peritoneal metastasis (PM) is an independent prognostic factor in gastric cancer (GC), however, the underlying mechanisms of PM occurrence remain unclear.

METHOD

The roles of DDR2 were investigated in GC and its potential relationship to PM, and orthotopic implants into nude mice were performed to assess the biological effects of DDR2 on PM.

RESULTS

Herein, DDR2 level is more significantly observed to elevate in PM lesion than the primary lesion. GC with DDR2-high expression evokes a worse overall survival (OS) in TCGA, similar results of the gloomy OS with high DDR2 levels are clarified via the stratifying stage of TNM. The conspicuously increased expression of DDR2 was found in GC cell lines, luciferase reporter assays verified that miR-199a-3p directly targeted DDR2 gene, which was correlated to tumor progression. We ulteriorly observed DDR2 participated in GC stemness maintenance via mediating pluripotency factor SOX2 expression and implicated in autophagy and DNA damage of cancer stem cells (CSCs). In particular, DDR2 dominated EMT programming through recruiting NFATc1-SOX2 complex to Snai1 in governing cell progression, controlling by DDR2-mTOR-SOX2 axis in SGC-7901 CSCs. Furthermore, DDR2 promoted the tumor peritoneal dissemination in gastric xenograft mouse model.

CONCLUSION

Phenotype screens and disseminated verifications incriminating in GC exposit the miR-199a-3p-DDR2-mTOR-SOX2 axis as a clinically actionable target for tumor PM progression. The herein-reported DDR2-based underlying axis in GC represents novel and potent tools for studying the mechanisms of PM.

Aberrant Expression of Serum MicroRNA-153 and -199a in Generalized Epilepsy and its Correlation with Drug Resistance

Background:

Epilepsy is one of the common neurological disorders affecting approximately 50 million people worldwide. Despite the recent introduction of new antiepileptic drugs, about one-third of patients with epilepsy have seizures refractory to pharmacotherapy. Early recognition of patients with drug-resistant epilepsy may help direct these patients to appropriate nonpharmacological treatment.

Purpose:

The possible use of serum microRNAs (miRNAs) as noninvasive biomarkers has been explored in various brain diseases, including epilepsy. In this study, we are aiming at analyzing the expression levels of circulating miRNA-153 and miRNA-199a in patients with generalized epilepsy and their correlation with drug resistance.

Methods:

Our study comprised 40 patients with generalized epilepsy and 20 healthy controls. 22 patients were drug-resistant and 18 patients were drug-responsive. The expression levels of miRNA-153 and -199a in serum were analyzed using quantitative real-time polymerase chain reaction. Data analysis was done by IBM SPSS Statistics 20.0.

Results:

The expression of miRNA-153 and -199a in serum was significantly downregulated in patients with generalized epilepsy compared with that of the healthy control ( P < .001). Combined expression level of serum miRNA-153 and -199a had a sensitivity of 85% and a specificity of 90% in the diagnosis of generalized epilepsy. Furthermore, the expression levels of miRNA-153 and -199a were significantly decreased in drug-resistant patients compared to the drug-responsive group, and the combination of both markers gave the best results in differentiating between the two groups.

Conclusion:

We suggest that serum miRNAs-153 and -199a expression levels could be potential noninvasive biomarkers supporting the diagnosis of generalized epilepsy. Moreover, they could be used for the early detection of refractory generalized epilepsy.

The Role of microRNAs in Multidrug Resistance of Glioblastoma

Glioblastoma (GBM) is an aggressive brain tumor that develops from neuroglial stem cells and represents a highly heterogeneous group of neoplasms. These tumors are predominantly correlated with a dismal prognosis and poor quality of life. In spite of major advances in developing novel and effective therapeutic strategies for patients with glioblastoma, multidrug resistance (MDR) is considered to be the major reason for treatment failure. Several mechanisms contribute to MDR in GBM, including upregulation of MDR transporters, alterations in the metabolism of drugs, dysregulation of apoptosis, defects in DNA repair, cancer stem cells, and epithelial-mesenchymal transition. MicroRNAs (miRNAs) are a large class of endogenous RNAs that participate in various cell events, including the mechanisms causing MDR in glioblastoma. In this review, we discuss the role of miRNAs in the regulation of the underlying mechanisms in MDR glioblastoma which will open up new avenues of inquiry for the treatment of glioblastoma.

miR-199a-3p/5p regulate tumorgenesis via targeting Rheb in non-small cell lung cancer

Lung cancer is one of the deadliest cancers, in which non-small cell lung cancer (NSCLC) accounting for 85% and has a low survival rate of 5 years. Dysregulation of microRNAs (miRNAs) can participate in tumor regulation and many major diseases. In this study, we found that miR-199a-3p/5p were down-expressed in NSCLC tissue samples, cell lines, and the patient sample database. MiR-199a-3p/5p overexpression could significantly suppress cell proliferation, migration ability and promote apoptosis. Through software prediction, ras homolog enriched in brain (Rheb) was identified as a common target of miR-199a-3p and miR-199a-5p, which participated in regulating mTOR signaling pathway. The same effect of inhibiting NSCLC appeared after down-regulating the expression of Rheb. Furthermore, our findings revealed that miR-199a can significantly inhibit tumor growth and metastasis in vivo, which fully demonstrates that miR-199a plays a tumor suppressive role in NSCLC. In addition, miR-199a-3p/5p has been shown to enhance the sensitivity of gefitinib to EGFR-T790M in NSCLC. Collectively, these results prove that miR-199a-3p/5p can act as cancer suppressor genes to inhibit the mTOR signaling pathway by targeting Rheb, which in turn inhibits the regulatory process of NSCLC. Thus, to investigate the anti-cancer effect of pre-miR-199a/Rheb/mTOR axis in NSCLC, miR-199a-3p and miR-199a-5p have the potential to become an early diagnostic marker or therapeutic target for NSCLC.

Crosstalk of Epigenetic and Metabolic Signaling Underpinning Glioblastoma Pathogenesis

Simple Summary

Epigenetic mechanisms can modulate key genes involved in the cellular metabolism of glioblastomas and participate in their pathogenesis by increasing their heterogeneity, plasticity, and malignancy. Although most epigenetic modifications can primarily promote the activity of metabolic pathways, they may also exert an inhibitory role. The detection of key metabolic alterations in gliomas regulated by epigenetic mechanisms will enable drug development and effective molecular targeting, improvement of therapeutic schemes, and patients’ management.

Abstract

Metabolic alterations in neoplastic cells have recently gained increasing attention as a main topic of research, playing a crucial regulatory role in the development and progression of tumors. The interplay between epigenetic modifications and metabolic pathways in glioblastoma cells has emerged as a key pathogenic area with great potential for targeted therapy. Epigenetic mechanisms have been demonstrated to affect main metabolic pathways, such as glycolysis, pentose phosphate pathway, gluconeogenesis, oxidative phosphorylation, TCA cycle, lipid, and glutamine metabolism by modifying key regulatory genes. Although epigenetic modifications can primarily promote the activity of metabolic pathways, they may also exert an inhibitory role. In this way, they participate in a complex network of interactions that regulate the metabolic behavior of malignant cells, increasing their heterogeneity and plasticity. Herein, we discuss the main epigenetic mechanisms that regulate the metabolic pathways in glioblastoma cells and highlight their targeting potential against tumor progression.

Prognostic Potential of MicroRNAs in Glioma Patients: A Meta-Analysis

Introduction MicroRNAs are a noncoding RNA involved in affecting several transcription and translation pathways. Their use has been discussed as potential predictors of several tumors. Their use as potential biomarker in glioma patients is still controversial. The purpose of this meta-analysis is to explore the possible role of such microRNAs in glioma patients.

Methods After an extensive literature search done on PubMed and Embase, 20 studies were chosen for our analyses with the 9 discussing 11 tumor promoting microRNAs and 11 studies discussing 11 tumor suppressing microRNAs. The data needed was extracted from these studies including the hazard ratio that was used as the effect size for the purpose of our analysis. The needed analysis was performed using Stata and Excel.

Results The pooled hazard ratio for our analysis with patients having a lower microRNA expression for tumor promoting microRNAs came to be 2.63 (p < 0.001), while the hazard ratio for patients with higher expression of tumor promoting microRNA was 2.47 (p < 0.001) with both results being statistically significant. However, as significant heterogeneity was observed a random effect model for analysis was used. Subgroup analysis was further performed using grade, cutoff value (mean or median), sample type (Serum or Blood), and Karnofsky performance score, all of them showing a high hazard ratio.

Conclusion Our results showed that both tumor inhibitory and promoting microRNA can be used as prognostic tool in glioma patients with a poorer prognosis associated with a lower expression in tumor suppressive and higher expression in tumor promoting microRNA, respectively. However, to support this, future studies on a much larger scale would be needed.

Exosomes and their Cargo as a New Avenue for Brain and Treatment of CNS-Related Diseases

Extracellular Vesicles (EVs), which belong to nanoscale vesicles, including microvesicles (MVs) and exosomes, are now considered a new important tool for intercellular neuronal communication in the Central Nervous System (CNS) under physiological and pathological conditions. EVs are shed into blood, peripheral body fluids and cerebrospinal fluid (CSF) by a large variety of cells.

EVs can act locally on neighboring and distant cells. EVs represent the fingerprints of the originating cells and can carry a variety of molecular constituents of their cell of origin, including protein, lipids, DNA and microRNAs (miRNAs).

The most studied EVs are the exosomes because they are ubiquitous and have the capacity to transfer cell-derived components and bioactive molecules to target cells. In this minireview, we focused on cell-cell communication in CNS mediated by exosomes and their important cargo as an innovative way to treat or follow up with CNS diseases.

Wnt and PI3K/Akt/mTOR Survival Pathways as Therapeutic Targets in Glioblastoma

Glioblastoma (GBM) is a devastating type of brain tumor, and current therapeutic treatments, including surgery, chemotherapy, and radiation, are palliative at best. The design of effective and targeted chemotherapeutic strategies for the treatment of GBM require a thorough analysis of specific signaling pathways to identify those serving as drivers of GBM progression and invasion. The Wnt/β-catenin and PI3K/Akt/mTOR (PAM) signaling pathways are key regulators of important biological functions that include cell proliferation, epithelial–mesenchymal transition (EMT), metabolism, and angiogenesis. Targeting specific regulatory components of the Wnt/β-catenin and PAM pathways has the potential to disrupt critical brain tumor cell functions to achieve critical advancements in alternative GBM treatment strategies to enhance the survival rate of GBM patients. In this review, we emphasize the importance of the Wnt/β-catenin and PAM pathways for GBM invasion into brain tissue and explore their potential as therapeutic targets.

Crosstalk between miRNA and PI3K/AKT/mTOR signaling pathway in cancer

Phosphoinositide-3 kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling pathway is one of the most important proliferative signaling pathways with critical undeniable function in various aspects of cancer initiation/progression, including proliferation, apoptosis, metastasis, angiogenesis, and drug resistance. On the other hand, numerous genetic alterations in the key genes involved in the PI3K/AKT/mTOR signaling pathway have been identified in multiple solid and hematological tumors. In addition, accumulating recent evidences have demonstrated a reciprocal interaction between this signaling pathway and microRNAs, a large group of small non-coding RNAs. Therefore, in this review, it was attempted to discuss about the interaction between key components of PI3K/AKT/mTOR signaling pathway with various miRNAs and their importance in cancer biology.

MicroRNAs' role in the environment-related non-communicable diseases and link to multidrug resistance, regulation, or alteration

The discovery of microRNAs (miRNAs) 20 years ago has advocated a new era of "small molecular genetics." About 2000 miRNAs are present that regulate one third of the genome. MiRNA dysregulated expression arising as a response to our environment insult or stress or changes may contribute to several diseases, namely non-communicable diseases, including tumor growth. Their presence in body fluids, reflecting level alteration in various cancers, merit circulating miRNAs as the "next-generation biomarkers" for early-stage tumor diagnosis and/or prognosis. Herein, we performed a comprehensive literature search focusing on the origin, biosynthesis, and role of miRNAs and summarized the foremost studies centering on miR value as non-invasive biomarkers in different environment-related non-communicable diseases, including various cancer types. Moreover, during chemotherapy, many miRNAs were linked to multidrug resistance, via modulating numerous, environment triggered or not, biological processes and/or pathways that will be highlighted as well.

Epigenetics of glioblastoma multiforme: From molecular mechanisms to therapeutic approaches

Glioblastoma multiforme (GBM) is the most common form of brain cancer and one of the most aggressive cancers found in humans. Most of the signs and symptoms of GBM can be mild and slowly aggravated, although other symptoms might demonstrate it as an acute ailment. However, the precise mechanisms of the development of GBM remain unknown. Due to the improvement of molecular pathology, current researches have reported that glioma progression is strongly connected with different types of epigenetic phenomena, such as histone modifications, DNA methylation, chromatin remodeling, and aberrant microRNA. Furthermore, the genes and the proteins that control these alterations have become novel targets for treating glioma because of the reversibility of epigenetic modifications. In some cases, gene mutations including P16, TP53, and EGFR, have been observed in GBM. In contrast, monosomies, including removals of chromosome 10, particularly q23 and q25-26, are considered the standard markers for determining the development and aggressiveness of GBM. Recently, amid the epigenetic therapies, histone deacetylase inhibitors (HDACIs) and DNA methyltransferase inhibitors have been used for treating tumors, either single or combined. Specifically, HDACIs are served as a good choice and deliver a novel pathway to treat GBM. In this review, we focus on the epigenetics of GBM and the consequence of its mutations. We also highlight various treatment approaches, namely gene editing, epigenetic drugs, and microRNAs to combat GBM.

Downregulation of miR-199a-3p in Hepatocellular Carcinoma and Its Relevant Molecular Mechanism via GEO, TCGA Database and In Silico Analyses

Existing reports have demonstrated that miR-199a-3p plays a role as a tumor suppressor in a variety of human cancers. This study aims to further validate the expression of miR-199a-3p in HCC and to explore its underlying mechanisms by using multiple data sets. Chip data or sequencing data and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were integrated to assess the expression of miR-199a-3p in HCC. The potential targets and transcription factor regulatory network of miR-199a-3p in HCC were determined and possible biological mechanism of miR-199a-3p was analyzed with bioinformatics methods. In the results, miR-199a-3p expression was significantly lower in HCC tissues compared to normal tissues according to chip data or sequencing data and qRT-PCR. Moreover, 455 targets of miR-199a-3p were confirmed, and these genes were involved in the PI3K-Akt signaling pathway, pathways in cancer, and focal adhesions. LAMA4 was considered a key target of miR-199a-3p. In CMTCN, 11 co-regulatory pairs, 3 TF-FFLs, and 2 composite-FFLs were constructed. In conclusion, miR-199a-3p was down regulated in HCC and LAMA4 may be a potential target of miR-199a-3p in HCC.

Hypoxia-Induced Glioma-Derived Exosomal miRNA-199a-3p Promotes Ischemic Injury of Peritumoral Neurons by Inhibiting the mTOR Pathway

The underlying molecular mechanisms that the hypoxic microenvironment could aggravate neuronal injury are still not clear. In this study, we hypothesized that the exosomes, exosomal miRNAs, and the mTOR signaling pathway might be involved in hypoxic peritumoral neuronal injury in glioma. Multimodal radiological images, HE, and HIF-1α staining of high-grade glioma (HGG) samples revealed that the peritumoral hypoxic area overlapped with the cytotoxic edema region and directly contacted with normal neurons. In either direct or indirect coculture system, hypoxia could promote normal mouse hippocampal neuronal cell (HT22) injury, and the growth of HT22 cells was suppressed by C6 glioma cells under hypoxic condition. For administrating hypoxia-induced glioma-derived exosomes (HIGDE) that could aggravate oxygen-glucose deprivation (OGD)/reperfusion neuronal injury, we identified that exosomes may be the communication medium between glioma cells and peritumoral neurons, and we furtherly found that exosomal miR-199a-3p mediated the OGD/reperfusion neuronal injury process by suppressing the mTOR signaling pathway. Moreover, the upregulation of miRNA-199a-3p in exosomes from glioma cells was induced by hypoxia-related HIF-1α activation. To sum up, hypoxia-induced glioma-derived exosomal miRNA-199a-3p can be upregulated by the activation of HIF-1α and is able to increase the ischemic injury of peritumoral neurons by inhibiting the mTOR pathway.

Reduced Expression of hsa-miR-338-3p Contributes to the Development of Glioma Cells by Targeting Mitochondrial 3-Oxoacyl-ACP Synthase (OXSM) in Glioblastoma (GBM)

Background

MicroRNAs have been identified as major regulators and therapeutic targets of glioblastoma (GBM). It is thus meaningful to study the miRNAs differentially expressed (DE-miRNAs) in GBM.

Materials and Methods

We performed a meta-analysis of previously published microarray data using the R-based “metaMA” package to identify DE-miRNAs.The biological processes of the DE-miRNAs were then analyzed using FunRich. KEGG pathways of the DE-miRNAs gene targets were analyzed by mirPath V.3. Luciferase activity assay was performed to validate that OXSM is a direct target of hsa-miR338-3p. Flow cytometry was used to detect the effects of miR-338-3p on GBM cell proliferation, apoptosis and cell cycle.

Results

DE-miRNAs in blood and brain tissue from GBM were identified. “Type I interferon signaling pathway” and “VEGF and VEGFR signaling network” were the most significantly enriched biological processes shared by all GBM types. In KEGG pathway analysis, DE-miRNAs both in blood and tissue show altered fatty acid biosynthesis. Further validation shows hsa-miR-338-3p regulates fatty acid metabolism by directly targeting OXSM gene. In addition, our data revealed an accelerated cell cycle and an anti-apoptotic role for OXSM in glioma cells, which has not been reported. Finally, we confirmed that hsa-miR-338-3p inhibitor antagonized the effect of downregulation of OXSM on cell cycle and apoptosis of GBM cells.

Conclusion

We revealed that hsa-miR-338-3p, down-regulated in GBM, may affect the biogenesis and rapid proliferation of glioma cells by regulating the level of OXSM, providing new insights into understanding the pathogenesis of GBM and developing strategies to improve GBM prognosis.

miR-199a-3p suppresses progression of esophageal squamous cell carcinoma through inhibiting mTOR/p70S6K pathway

Dysregulation of microRNA contributes to multiple tumorigenic processes. Although downregulation of miR-199a-3p has been shown in many cancers, its effects on esophageal squamous cell carcinoma (ESCC) and the regulatory mechanism are still obscure. Here, we aim to evaluate the biological function and underlying mechanisms of miR-199a-3p in ESCC as well as its value to clinical treatment of ESCC. We first analyzed expression of miR-199a-3p in esophageal cancer by bioinformatic analysis and found that there were different opinions about expression of miR-199a-3p in esophageal cancer, and the following qRT-PCR assay demonstrated which was markedly downregulated in ESCC cells. Next, we increased the expression of miR-199a-3p in ESCC cells using miR-199a-3p mimics and demonstrated that overexpression of miR-199a-3p significantly inhibited cell proliferation, migration and invasion, as well as induced cell cycle retard and promoted apoptosis in ESCC. Furthermore, we explored the functional targets of miR-199a-3p and identified that overexpression of miR-199a-3p inhibited mTOR/p70S6K pathway, but stimulated PI3K/Akt pathway. Finally, we demonstrated that overexpression of miR-199a-3p enhanced proliferation-inhibiting effects of MK2206, an inhibitor of Akt, to ESCC cells, which might be related that MK2206 eliminated the activation of miR-199a-3p to p-Akt. These findings discover that miR-199a-3p might participate in the carcinogenesis process of ESCC, which provides a new insight for treatment of ESCC.

MicroRNA-199a-3p inhibits angiogenesis by targeting the VEGF/PI3K/AKT signalling pathway in an in vitro model of diabetic retinopathy

BACKGROUND

Diabetic retinopathy (DR) is a major inducer of blindness and visual impairment. As a critical cause for DR, hyperglycaemia is able to trigger multiple biochemical alterations. MiRNAs, which contain various functions, can effectively regulate blood glucose levels. This research aims to confirm the roles of miRNA-199a-3p in the progression of angiogenesis in an in vitro model of DR.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was carried to determine the expression levels of miR-199a-3p and VEGF in both hRMECs and APRE-19 cells. The luciferase reporter assay was used to study the interaction between miR-199a-3p and VEGF. Western blot assay was conducted to examine the expression levels of VEGF and the PI3K/AKT signalling pathway. The cell proliferation capacity was detected via the CCK-8 test. The impact of miR-199a-3p on migration was determined using Transwell and wound healing assays. A Matrigel tube formation assay was employed to determine the vascular formation of hRMECs. Flow cytometry was used to determine cell apoptosis in the presence of LY294002 as a PI3K inhibitor.

RESULTS

Our results showed that high glucose (HG) decreased the relative expression level of miR-199a-3p but increased VEGF expression in hRMECs and APRE-19 cells. MiR-199a-3p inhibitor augmented cell growth, migration and angiogenesis of hRMECs. Moreover, upregulation of miR-199a-3p evidently alleviated the increases in cell proliferation, migration and angiogenesis caused by HG. In addition, the luciferase reporter assay indicated that miR-199a-3p directly targeted VEGF. The overexpression of miR-199a-3p obviously restrained the HG-stimulated PI3K/AKT signalling pathway and angiogenesis, which could be further inhibited by LY294002. Moreover, LY294002 could slightly ameliorate the miR-199a-3p inhibitor-stimulated PI3K/AKT signalling pathway and angiogenesis.

CONCLUSION

MiR-199a-3p upregulation ameliorated HG-stimulated angiogenesis of hRMECs by modulating the PI3K/AKT pathway through inhibiting VEGF. Although retinal neovascularization in vivo has not been studied, these in vitro findings provide more evidence for the role of miR-199a-3p upregulation against HG-induced angiogenesis.

LncRNA LINC01140 Inhibits Glioma Cell Migration and Invasion via Modulation of miR-199a-3p/ZHX1 Axis

PURPOSE

Glioma is an aggressive tumor from the nervous system, which causes more than 70% of primary malignant brain tumors. Considering its severe malignancy, there is an urgent need to investigate more practical markers to understand the pathogenesis of glioma, and potential treatment methods for glioma patients. In the paper, we are focused on examining the roles of LINC01140, miR-199a-3p, and ZHX1 in the progression of gliomas, as well as their inner associations and modulation mechanisms.

METHODS

qRT-PCR was employed to examine the expression levels of LINC01140 and miR-199a-3p. We measured the expressions of ZHX1 via qRT-PCR and Western blotting. CCK8 assays, migration assays, and invasion assays were carried out to determine the cell viabilities and abilities of migration and invasion. We also conducted in vivo tumor growth experiments to investigate the roles of LINC01140 in glioma developments.

RESULTS

The expressions of LINC01140 were promoted in glioma. Silencing LINC01140 could inhibit glioma cell viabilities, migration, and invasion. In our experiments, miR-199a-3p was inhibited in glioma. LINC01140 negatively regulated the expressions of miR-199a-3p in glioma. MiR-199a-3p could target ZHX1 to inhibit its expression in glioma cells.

CONCLUSION

LINC01140 could promote glioma developments by modulating the miR-199a-3p/ZHX1 axis.

Blocking lncRNA MALAT1/miR-199a/ZHX1 Axis Inhibits Glioblastoma Proliferation and Progression

Zinc fingers and homeoboxes 1 (ZHX1) is a transcription repressor that has been implicated in the tumorigenesis and progression of diverse tumors. The functional role and regulating mechanism of ZHX1 has not been elucidated in glioblastoma (GBM). Previous reports have suggested that a large number of non-coding RNAs play a vital role in glioma initiation and progression. This study aimed to investigate the functional role and co-regulatory mechanisms of the metastasis-associated lung adenocarcinoma transcript-1 (MALAT1)/ microRNA-199a (miR-199a)/ZHX1 axis in GBM. We analyzed the expression of the MALAT1/miR-199a/ZHX1 axis and its correlation with patients' overall survival using two different glioma gene-expression datasets. A series of in vitro and in vivo studies including dual luciferase reporter assay, fluorescence in situ hybridization (FISH), RNA immunoprecipitation, and pull-down experiments were completed to elucidate the biological significance of the MALAT1/miR-199a/ZHX1 axis in promoting glioma proliferation and progression. Elevated ZHX1 expression correlated with poor prognosis in GBM patients, and in vitro studies demonstrated that ZHX1 attenuated GBM cell apoptosis by downregulation of pro-apoptotic protein (Bax) and upregulation of anti-apoptotic protein (Bcl-2). Furthermore, knockdown of MALAT1 inhibited GBM proliferation and progression in vitro and reduced tumor volume and prolonged survival in an orthotopic GBM murine model. Finally, we demonstrated that MALAT1 promoted ZHX1 expression via acting as a competing endogenous RNA by sponging miR-199a. The MALAT1/miR-199a/ZHX1 axis promotes GBM cell proliferation and progression in vitro and in vivo, and its expression negatively correlates with GBM patient survival. Blocking the MALAT1/miR-199a/ZHX1 axis can serve as a novel therapeutic strategy for treating GBM.

Advancing towards Effective Glioma Therapy: MicroRNA Derived from Umbilical Cord Mesenchymal Stem Cells' Extracellular Vesicles

A glioma, especially a grade IV glioblastoma, is a malignant tumour with a poor prognosis despite growing medical advancements. Researchers have been looking for better and more effective treatments targeting the molecular pathways of gliomas due to glioblastomas’ ability to develop resistance to chemotherapies. Moreover, glioma stem cells (GSC) contribute to maintaining the glioma population, which benefits from its ability to self-renew and differentiate. Recent research has reported that through the introduction of umbilical cord mesenchymal stem cells (UCMSC) into glioma cells, the growth and development of the glioma cells can be downregulated. It has more currently been found out that UCMSC release extracellular vesicles (EVs) containing miRNA that are responsible for this phenomenon. Therefore, this review analyses literature to discuss all possible miRNAs contained within the UCMSC’s EVs and to elaborate on their molecular mechanisms in halting gliomas and GSC growth. This review will also include the challenges and limitations, to account for which more in vivo research is suggested. In conclusion, this review highlights how miRNAs contained within UCMSC’s EVs are able to downregulate multiple prominent pathways in the survival of gliomas.

Exosomes derived from microRNA-199a-overexpressing mesenchymal stem cells inhibit glioma progression by down-regulating AGAP2

Accumulating evidence has implied that microRNAs (miRNAs) are implicated in glioma progression, and genetically engineered mesenchymal stem cells can help to inhibit tumor growth of glioma. Herein we hypothesized that miR-199a could be delivered by mesenchymal stem cells to glioma cells through exosomes and thus prevent the glioma development by down-regulating ArfGAP with GTPase domain, ankyrin repeat and PH domain 2 (AGAP2). The expression pattern of miR-199a and AGAP2 was characterized in glioma tissues and cells using RNA polymerase chain reaction quantification, immunohistochemical staining and Western blot assays. Mesenchymal stem cells transfected with miR-199a mimic or their derived exosomes were co-cultured with U251 cells. The biological behaviors as well as chemosensitivity of U251 cells were assessed to explore the involvement of miR-199a/AGAP2 in glioma. MiR-199a was poorly expressed in glioma tissue and cells while AGAP2 was highly expressed. Mesenchymal stem cells delivered miR-199a to the glioma cells via the exosomes, which resulted in the suppression of the proliferation, invasion and migration of glioma cells. Besides, mesenchymal stem cells over-expressing miR-199a enhanced the chemosensitivity to temozolomide and inhibited the tumor growth in vivo. Taken together, mesenchymal stem cell-derived exosomal miR-199a can inhibit the progression of glioma by down-regulating AGAP2.

The Role of Cancer Stem Cells and Mechanical Forces in Ovarian Cancer Metastasis

Ovarian cancer is an extremely lethal gynecologic disease; with the high-grade serous subtype predominantly associated with poor survival rates. Lack of early diagnostic biomarkers and prevalence of post-treatment recurrence, present substantial challenges in treating ovarian cancers. These cancers are also characterized by a high degree of heterogeneity and protracted metastasis, further complicating treatment. Within the ovarian tumor microenvironment, cancer stem-like cells and mechanical stimuli are two underappreciated key elements that play a crucial role in facilitating these outcomes. In this review article, we highlight their roles in modulating ovarian cancer metastasis. Specifically, we outline the clinical relevance of cancer stem-like cells, and challenges associated with their identification and characterization and summarize the ways in which they modulate ovarian cancer metastasis. Further, we review the mechanical cues in the ovarian tumor microenvironment, including, tension, shear, compression and matrix stiffness, that influence (cancer stem-like cells and) metastasis in ovarian cancers. Lastly, we outline the challenges associated with probing these important modulators of ovarian cancer metastasis and provide suggestions for incorporating these cues in basic biology and translational research focused on metastasis. We conclude that future studies on ovarian cancer metastasis will benefit from the careful consideration of mechanical stimuli and cancer stem cells, ultimately allowing for the development of more effective therapies.

Emerging roles of microRNAs in regulating the mTOR signaling pathway during tumorigenesis

The mammalian target of rapamycin (mTOR) is a large Ser/Thr protein kinase that belongs to the phosphoinositide 3-kinase (PI3K) family and mediates various physiological and pathological processes, especially cell proliferation, protein synthesis, autophagy, and cancer development. The mTOR expression is transient and tightly regulated in normal cells, but it is overactivated in cancer cells. Recently, several studies have indicated that microRNAs (miRNAs) play a critical role in the regulation of mTOR and mTOR-associated processes, some acting as inhibitors and the others as activators. Although it is still in infancy, the strategy of combining both miRNAs and mTOR inhibitors might provide an approach to selectively sensitizing tumor cells to chemotherapy-induced DNA damage and subsequently attenuating the tumor cell growth and apoptosis.

The Roles of miRNAs in Medulloblastoma: A Systematic Review

Medulloblastoma is considered one of the most threatening malignant brain tumors with an extremely high mortality rate in children. In the medulloblastoma, there are several genes and mutations found to work in an unregulated manner that works together to push the cells into a cancerous state. With the discovery of non-coding RNAs such as microRNAs (miRNAs), it has been shown that a different layer of gene regulations may be disrupted which would cause cancer. This fact led scientists to put their focus on the role of miRNAs in cancer. A mature miRNA contains a seed sequence which gives the miRNA to identify and attach to the interest mRNA; this attachment may lead degradation of mRNA or suppress of translation of the mRNA. The expression of miRNAs in medulloblastoma shows that some of these non-coding RNAs are overexpressed (OncomiRs) which help cells to proliferate and keep their stemness features. On the other hand, there are other forms of these miRNAs which normally inhibit cell proliferation and promote cell differentiation (tumor suppressor). These are down-regulated during cancer progression. In this systematic review, we attempted to gather several important studies on miRNAs’ role in medulloblastoma tumors and the importance of these non-coding RNAs in the future study of cancer.

p53 induces miR-199a-3p to suppress mechanistic target of rapamycin activation in cisplatin-induced acute kidney injury

How p53 participates in acute kidney injury (AKI) progress and what are the underlying mechanisms remain illusive. For this issue, it is important to probe into the role of p53 in cisplatin-induced AKI. We find that p53 was upregulated in cisplatin-induced AKI, yet, pifithrin-α inhibites the p53 expression to attenuated renal injury and cell apoptosis both in vivo cisplatin-induced AKI mice and in vitro HK-2 human renal tubular epithelial cells. To knock down p53 by siRNA significantly decreased the miRNA, miR-199a-3p, expression in HK-2 cells. Blockade of miR-199a-3p significantly reduced cisplatin-induced cell apoptosis and inhibited caspase-3 activity. Mechanistically, we identified that miR-199a-3p directly bound to mechanistic target of rapamycin (mTOR) 3'-untranslated region and overexpressed miR-199a-3p reduce the expression and phosphorylation of mTOR. Furthermore, we demonstrated that p53 inhibited mTOR activation through activating miR-199a-3p. In conclusion, our findings reveal that p53, upregulating the expression of miR-199a-3p affects the progress of cisplatin-induced AKI, which might provide a promising therapeutic target of AKI.

Painful neurotrophins and their role in visceral pain

Beyond their well-known role in embryonic development of the central and peripheral nervous system, neurotrophins, particularly nerve growth factor and brain-derived neurotrophic factor, exert an essential role in pain production and sensitization. This has mainly been studied within the framework of somatic pain, and even antibodies (tanezumab and fasinumab) have recently been developed for their use in chronic somatic painful conditions, such as osteoarthritis or low back pain. However, data suggest that neurotrophins also exert an important role in the occurrence of visceral pain and visceral sensitization. Visceral pain is a distressing symptom that prompts many consultations and is typically encountered in both 'organic' (generally inflammatory) and 'functional' (displaying no obvious structural changes in routine clinical evaluations) disorders of the gut, such as inflammatory bowel disease and irritable bowel syndrome, respectively. The present review provides a summary of neurotrophins as a molecular family and their role in pain in general and addresses recent investigations of the involvement of nerve growth factor and brain-derived neurotrophic factor in visceral pain, particularly that associated with inflammatory bowel disease and irritable bowel syndrome.

Epigenetic modulation of metabolism in glioblastoma

Epigenetic and metabolic alterations incancer cells are highly associated. Glioblastoma multiforme (GBM) is a complicated pathological process with dysregulated methylation and histone modifications. Metabolic modulation of epigenetics in gliomas was previously summarized. However, epigenetic modulation is also important in metabolic decision. Recently, there has been a tremendous increase in understanding of DNA methylation, chromatin modulation, and non-coding RNAs in the regulation of cell metabolism, especially glycolytic metabolism in GBM. In this review, we summarize DNA methylation, histone alteration, and non-coding RNA mediated epigenetic modulation of metabolism in GBM and discuss the future research directions in this area and its applications in GBM treatment.

Aberrant miRNAs Regulate the Biological Hallmarks of Glioblastoma

GBM is the highest incidence in primary intracranial malignancy, and it remains poor prognosis even though the patient is gave standard treatment. Despite decades of intense research, the complex biology of GBM remains elusive. In view of eight hallmarks of cancer which were proposed in 2011, studies related to the eight biological capabilities in GBM have made great progress. From these studies, it can be inferred that miRs, as a mode of post-transcriptional regulation, are involved in regulating these malignant biological hallmarks of GBM. Herein, we discuss state-of-the-art research on how aberrant miRs modulate the eight hallmarks of GBM. The upregulation of 'oncomiRs' or the genetic loss of tumor suppressor miRs is associated with these eight biological capabilities acquired during GBM formation. Furthermore, we also discuss the applicable clinical potential of these research results. MiRs may aid in the diagnosis and prognosis of GBM. Moreover, miRs are also therapeutic targets of GBM. These studies will develop and improve precision medicine for GBM in the future.

MiR-199a-3p acts as a tumor suppressor in clear cell renal cell carcinoma

OBJECTIVES

To explore the biological function and mechanism of miR-199a-3p in clear cell renal cell carcinoma (CCRCC).

METHODS

We investigated the expression of miR-199a-3p in CCRCC through quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Over expression of miR-199a-3p was performed in CCRCC cell lines, and cell growth curve, colony formation capacity, cell invasion, wound healing and cell apoptosis assay were used for investigating the roles of miR-199a-3p in CCRCC.

RESULTS

The expression of miR-199a-3p in CCRCC tissues was significantly lower than that in para-carcinoma tissues. Functional assay showed that over expression of miR-199a-3p influenced cell growth, colony formation, cell invasion, cell migration and cell apoptosis in CCRCC cell lines.

CONCLUSIONS

Our work suggested that miR-199a-3p was related to cell growth, colony formation, cell invasion, cell migration and cell apoptosis, which might act as a tumor suppressor in CCRCC.

MiR-199a-3p enhances cisplatin sensitivity of cholangiocarcinoma cells by inhibiting mTOR signaling pathway and expression of MDR1

Several studies have reported reduced miRNA-199a-3p (miR-199a-3p) in different human malignancies, however, little is known about miR-199a-3p in cholangiocarcinoma cells. In this study, we demonstrate the essential role and mechanism of miR-199a-3p in regulating cisplatin sensitivity in cholangiocarcinoma cell lines. Using a CCK-8 cell counting assay we found that expression of miR-199a-3p was positively correlated with cisplatin sensitivity in cholangiocarcinoma cell lines. MiR-199a-3p overexpression could decrease the proliferation rate and increase apoptosis of cholangiocarcinoma cells in the presence of cisplatin, while miR-199a-3p inhibition had the opposite effect. Further study demonstrated that mTOR was the target gene of miR-199a-3p, and that miR-199a-3p mimics could inhibit expression of mTOR, which consequently reduced the phosphorylation of its downstream proteins 4EBP1 and p70s6k. Rescue experiments proved that miR-199a-3p could increase the cisplatin sensitivity of cholangiocarcinoma cell lines by regulating mTOR expression. Moreover, we also found that miR-199a-3p overexpression could reduce cisplatin induced MDR1 expression by decreasing the synthesis and increasing the degradation of MDR1, thus enhancing the effectiveness of cisplatin in cholangiocarcinoma. In conclusion, miR-199a-3p could increase cisplatin sensitivity of cholangiocarcinoma cell lines by inhibiting the activity of the mTOR signaling pathway and decreasing the expression of MDR1.

mTOR signaling-related MicroRNAs and Cancer involvement

MicroRNAs (miRNAs) are a class of single-stranded RNAs, 18-23 nucleotides in length that regulate gene expression at the post-transcriptional level. Dysregulation of miRNAs has been closely associated with the development of cancer. In the process of tumorigenesis, mammalian target of rapamycin (mTOR) plays important roles, and the mTOR signaling pathway is aberrant in various types of human cancers, including non-small cell lung cancer (NSCLC), breast cancer, prostate cancer, as well as others. However, the relationship between miRNAs and the mTOR signaling pathway is indistinct. Herein, we not only summarize the progress of miRNAs and the mTOR signaling pathway in cancers, but also highlight their role in the diagnosis and treatment in the clinic.

Serum and Extracellular Vesicle MicroRNAs miR-423, miR-199, and miR-93* As Biomarkers for Acute Graft-versus-Host Disease

Acute graft-versus-host disease (aGvHD) is a major cause of adverse outcome in hematopoietic stem cell transplantation (HSCT), with a high incidence (20–50%). A novel, non-invasive diagnostic test to predict for prevalence and severity would enable improved prophylaxis and reduce morbidity. Circulatory microRNAs (miRNAs) miR-423, miR-199, miR-93*, and miR-377 have previously been associated with aGvHD in post-HSCT patient plasma, but validation is lacking and their expression within extracellular vesicles (EVs) has not been explored. This study replicated elevated serum expression of miR-423 (p < 0.001), miR-199 (p = 0.04), miR-93* (p < 0.001), and miR-377 (p = 0.03) in aGvHD, using a prognostic cohort of day 14 (D14) post-HSCT patient samples (n = 81). Expression also associated with disease severity. Further analysis at aGvHD diagnosis in an independent cohort (n = 65) confirmed high miR-423 (p = 0.02), miR-199 (p = 0.007), and miR-93* (p = 0.004) expression at disease onset. Investigation of expression patterns during early HSCT sequential timepoints (pre-HSCT to D28) identified elevated miRNAs at D7 post-HSCT in all transplant patients. In a novel investigation of miRNA expression in serum EVs (n = 15), miR-423 (p = 0.09), miR-199 (p = 0.008), and miR-93* (p = 0.001) levels were lower at D14 in patients who later developed aGvHD, and this was replicated for miR-423 (p = 0.02) and miR-199 (p = 0.04) (n = 47). Comparing serum to circulating EVs, at D14 patients remaining aGvHD-free had higher expression of miR-423 (p = 0.03), miR-199 (p = 0.009), and miR-93* (p = 0.002) in the EV fraction. Results verify the capacity for circulating miR-423, miR-199, and miR-93* as diagnostic and prognostic aGvHD biomarkers. The novel finding of their differential expression in EVs suggests a potential role in aGvHD etiology.

MicroRNA Regulation of Glycolytic Metabolism in Glioblastoma

Glioblastoma (GBM) is the most aggressive and common malignant brain tumour in adults. A well-known hallmark of GMB and many other tumours is aerobic glycolysis. MicroRNAs (miRNAs) are a class of short nonprotein coding sequences that exert posttranscriptional controls on gene expression and represent critical regulators of aerobic glycolysis in GBM. In GBM, miRNAs regulate the expression of glycolytic genes directly and via the regulation of metabolism-associated tumour suppressors and oncogenic signalling pathways. This review aims to establish links between miRNAs expression levels, the expression of GBM glycolytic regulatory genes, and the malignant progression and prognosis of GBM. In this review, the involvement of 25 miRNAs in the regulation of glycolytic metabolism of GBM is discussed. Seven of these miRNAs have been shown to regulate glycolytic metabolism in other tumour types. Further eight miRNAs, which are differentially expressed in GBM, have also been reported to regulate glycolytic metabolism in other cancer types. Thus, these miRNAs could serve as potential glycolytic regulators in GBM but will require functional validation. As such, the characterisation of these molecular and metabolic signatures in GBM can facilitate a better understanding of the molecular pathogenesis of this disease.

Regulation of transient receptor potential cation channel subfamily V1 protein synthesis by the phosphoinositide 3-kinase/Akt pathway in colonic hypersensitivity

The transient receptor potential cation channel subfamily V member 1 (TRPV1), also known as the capsaicin receptor or vanilloid receptor 1 (VR1), is expressed in nociceptive neurons in the dorsal root ganglia (DRG) and participates in the transmission of pain. The present study investigated the underlying molecular mechanisms by which TRPV1 was regulated by nerve growth factor (NGF) signaling pathways in colonic hypersensitivity in response to colitis. We found that during colitis TRPV1 protein levels were significantly increased in specifically labeled colonic afferent neurons in both L1 and S1 DRGs. TRPV1 protein up-regulation in DRG was also enhanced by NGF treatment. We then found that TRPV1 protein up-regulation in DRG was regulated by activation of the phosphoinositide 3-kinase (PI3K)/Akt pathway both in vivo and in vitro. Suppression of endogenous PI3K/Akt activity during colitis or NGF treatment with a specific PI3K inhibitor LY294002 reduced TRPV1 protein production in DRG neurons, and also reduced colitis-evoked TRPV1-mediated visceral hypersensitivity tested by hyper-responsiveness to colorectal distention (CRD) and von Frey filament stimulation of abdomen. Further studies showed that TRPV1 mRNA levels in the DRG were not regulated by either colitis or NGF. We then found that an up-regulation of the protein synthesis pathway was involved by which both colitis and NGF caused a PI3K-dependent increase in the phosphorylation level of eukaryotic translation initiation factor 4E-binding protein (4E-BP)1. These results suggest a novel mechanism in colonic hypersensitivity which involves PI3K/Akt-mediated TRPV1 protein, not mRNA, up-regulation in primary afferent neurons, likely through activation of the protein synthesis pathways.

Screening candidate microRNAs (miRNAs) in different lambskin hair follicles in Hu sheep

Hu sheep lambskin is a unique white lambskin from China that exhibits three types of flower patterns, including small waves, medium waves, and large waves, with small waves considered the best quality. However, our understanding of the molecular mechanism underlying flower pattern formation in Hu sheep lambskin is limited. The aim of the present study was to further explore the relevance between candidate microRNAs (miRNAs) and developmental characteristics of hair follicles and screen miRNAs for later functional validation. Herein, we employed Illumina Hiseq 2500 to identify differentially expressed miRNAs in hair follicles of different flower patterns with small, medium, and large waves to construct a comprehensive sequence database on the mechanism of hair follicle development. Paraffin sections of lambskin tissue were prepared to assess the structure of different hair follicles. Expression levels of candidate miRNAs in different flower patterns were analyzed by relative quantitation using real-time PCR, combined with histological observation and micro-observation technologies, and the correlation between expression levels of candidate miRNAs and histological properties of hair follicles was analyzed by using SPSS 17.0. A total of 522 differentially expressed miRNAs were identified, and RNA-seq analysis detected 7,266 target genes in different groups of flower patterns. Gene ontological analysis indicated these target genes were mainly involved in cell proliferation, differentiation, growth, apoptosis, and ion transport, and 14 miRNAs, including miR-143, miR-10a, and let-7 were screened as candidate miRNAs in Hu sheep hair follicle growth and development. In the same field of vision, variance analysis showed that the number of secondary follicles in small waves was significantly larger than that in large and medium waves (P<0.01); the diameter of the primary and secondary follicles in large waves was respectively larger than those in medium and small waves (P<0.01). Combined with correlation analysis between miRNA expression and histological properties of hair follicles, highly significant differences in miRNA-143 expression levels between large and small waves were observed (P<0.01), and significant differences in the miRNA-10a expression levels between large and small waves (P<0.05) and in let-7i expression levels between large and medium waves were observed (P<0.05). Significant differences in the expression of novel miRNAs of NW_004080184.1_6326 between medium and large waves were detected (P<0.05), and highly significant differences between medium and small waves were observed (P<0.01). Highly significant differences in the expression level of NW_004080165.1_8572 between medium and large and small waves (P<0.01), in that of NW_004080181.1_3961 between medium and small waves (P<0.01), and in that of NW_004080190.1_13733 between medium and large waves were observed, whereas no significant differences in the other miRNAs among large, medium, and small waves were detected. Overall, the present study showed that miRNA-143, miRNA-10a, let-7i, NW_004080184.1_6326, NW_004080165.1_8572, NW_004080181.1_3961, and NW_004080190.1_13733 could be considered as important candidate genes, indicating these seven miRNAs may play significant roles in hair follicle growth and development in Hu sheep lambskin.

SNHG1 lncRNA negatively regulates miR-199a-3p to enhance CDK7 expression and promote cell proliferation in prostate cancer

Long noncoding RNAs (lncRNAs) have been reported to play vital roles in the development of human cancers, but our understandings of most lncRNAs in cancers are still limited. Recently, accumlating evidences have showed that many RNA transcripts could function as competing endogenous RNAs (ceRNAs) by competitively binding common microRNAs. In this study, we demonstrated that a lncRNA, Small Nucleolar RNA Host Gene 1 (SNHG1), as a ceRNA for miR-199a-3p, played a critical role in prostate cancer cell proliferation. We found that SNHG1 was aberrantly up-regulated in prostate carcinoma tissues; while, miR-199a-3p was abnormally down-regulated. The level of SNHG1 in prostate cancer was significantly negatively correlated with that of miR-199a-3p. Our data indicated that SNHG1 could interact with miR-199a-3p and inhibit the activity of miR-199a-3p in prostate cancer cells. In addition, miR-199a-3p could target the 3' UTR of CDK7 and suppress CDK7 expression. More importantly, SNHG1 increased CDK7 expression by competitively binding miR-199a-3p, and then promoted cell proliferation and cell cycle progression in prostate cancer. Taken together, these findings elucidated a novel mechanism of prostate cancer progression. Thus, SNHG1 might serve as a potential target for prostate cancer therapies.

Roles of zinc-fingers and homeoboxes 1 during the proliferation, migration, and invasion of glioblastoma cells

Zinc-fingers and homeoboxes 1 (ZHX1) is a nuclear transcription repressor and known to be involved in cell differentiation and tumorigenesis. However, the pathophysiological roles of ZHX1 have not been characterized in glioblastoma. We examined ZHX1 expression in glioblastoma patients' tissues and analyzed overall survival of the patients based on expression level of ZHX1. We also examined the effects of ZHX1 on proliferation and motility of glioblastoma cells. In silico analysis and immunohistochemical studies showed that the messenger RNA and protein expressions of ZHX1 were higher in the tissues of glioblastoma patients than in normal brain tissues, and that its overexpression was associated with reduced survival. In vitro, the downregulation of ZHX1 decreased the proliferation, migration, and invasion of glioblastoma cells, whereas its upregulation had the opposite effects. In addition, we showed ZHX1 could contribute to glioblastoma progression via the regulations of TWIST1 and SNAI2. Taken together, this study demonstrates that ZHX1 plays crucial roles in the progression of glioblastoma, and its findings suggest that ZHX1 be viewed as a potential prognostic maker and therapeutic target of glioblastoma.

Emerging Role of MicroRNAs in mTOR Signaling

Mechanistic target of rapamycin (mTOR) is a conserved serine/threonine kinase that plays a critical role in the control of cellular growth and metabolism. Hyperactivation of mTOR pathway is common in human cancers, driving uncontrolled proliferation. MicroRNA (miRNA) is a class of short noncoding RNAs that regulate the expression of a wide variety of genes. Deregulation of miRNAs is a hallmark of cancer. Recent studies have revealed interplays between miRNAs and the mTOR pathway during cancer development. Such interactions appear to provide a fine-tuning of various cellular functions and contribute qualitatively to the behavior of cancer. Here we provide an overview of current knowledge regarding the reciprocal relationship between miRNAs and mTOR pathway: regulation of mTOR signaling by miRNAs and control of miRNA biogenesis by mTOR. Further research in this area may prove important for the diagnosis and therapy of human cancer.

Expression of Glucose-Regulated Protein 78 and miR-199a in Rat Brain After Fatal Ligature Strangulation

The roles of endoplasmic reticulum (ER) stress and microRNA in the brain tissue after fatal mechanical asphyxia have not been clearly elucidated. We examined the expression of glucose-regulated protein 78 (GRP78), the key regulator of unfolded protein response, and miR-199a in the brain tissues of rats subjected to fatal ligature strangulation to understand the roles of ER stress and microRNA in ligature strangulation. The expressions of GRP78 and miR-199a in rat cortex, hippocampi, and midbrain were measured by immunohistochemistry and Western blot analysis in a rat model of ligature strangulation. Furthermore, the levels of miR-199a-3p and miR-199a-5p were detected by real-time fluorescent quantitative polymerase chain reaction. Glucose-regulated protein 78 was highly expressed in the cortex and midbrain in the ligature strangulation group (P < 0.01) when compared with the control group. The expression of GRP78 in the hippocampi showed no significant difference between the 2 groups. miR-199a-3p in the cortex and midbrain was significantly down-regulated in the ligature strangulation group (P < 0.01). However, miR-199a-5p in each brain region showed no significant difference between the 2 groups. In conclusion, ER stress was involved in the physiological and pathological processes of ligature strangulation. Furthermore, upstream miR-199a may play an important regulatory role in mechanical asphyxia.

The microRNA expression profile of mouse Müller glia in vivo and in vitro

The profile of miRNAs in mature glia is not well characterized, and most studies have been done in cultured glia. In order to identify the miRNAs in adult and young (postnatal day 11/12) Müller glia of the neural retina, we isolated the Müller glia from Rlbp-CreER: Stop^f/f-tdTomato mice by means of fluorescent activated cell sorting and analyzed their miRNAs using NanoStrings Technologies^®. In freshly isolated adult Müller glia, we identified 7 miRNAs with high expression levels in the glia, but very low levels in the retinal neurons. These include miR-204, miR-9, and miR-125-5p. We also found 15 miRNAs with high levels of expression in both neurons and glia, and many miRNAs that were enriched in neurons and expressed at lower levels in Müller glia, such as miR-124. We next compared miRNA expression of acutely isolated Müller glia with those that were maintained in dissociated culture for 8 and 14 days. We found that most miRNAs declined in vitro. Interestingly, some miRNAs that were not highly expressed in adult Müller glia increased in cultured cells. Our results thus show the miRNA profile of adult Müller glia and the effects of cell culture on their levels.

Serum microRNA-199a/b-3p as a predictive biomarker for treatment response in patients with hepatocellular carcinoma undergoing transarterial chemoembolization

Objective

The aim of this study was to investigate whether the level of serum microRNA-199a/b-3p (miR-199a/b-3p) can serve as a predictor of treatment response to transarterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC).

Methods

Serum miR-199a/b-3p expression level was measured in 132 patients with HCC before TACE (t1) and 3–5 days after TACE (t2). Additionally, 126 patients of these 132 patients had levels measured 4 weeks after TACE (t3) and 3–5 days after second TACE (t4). Serum miR-199a/b-3p expression levels were compared with those of 50 healthy controls. Correlations between miR-199a/b-3p expression levels and clinicopathologic factors and tumor responsiveness were analyzed. The modified Response Evaluation Criteria in Solid Tumors assessment was conducted at t3.

Results

A lower mean baseline miR-199a/b-3p expression level was observed in patients with HCC compared with healthy controls (0.68±0.81 vs 2.50±2.16, P<0.001). A negative correlation between baseline miR-199a/b-3p expression levels and tumor size (P<0.001) was observed. The nonresponder group had significantly lower miR-199a/b-3p expression levels than the responder group at t1 (0.77±1.09 vs 1.96±1.32, P<0.001). In addition, the decrease in miR-199a/b-3p at t2 was greater in the responder group than in the nonresponder group (P=0.011). A higher proportion of the responder group achieved a >25% decrease in serum miR-199a/b-3p expression levels compared with the nonresponder group (64% vs 39%).

Conclusion

Serum miR-199a/b-3p may represent a novel biomarker for predicting efficacy of TACE in patients with HCC.