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The objective of the present study was to explore the function and mechanism of long noncoding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (NEAT1) in pulmonary fibrosis (PF) progression. HPAEpic cells and A549 cells were exposed to hypoxic conditions to establish an in vitro model. Cell apoptosis was detected by TUNEL assay, and inflammatory cytokine levels were detected by ELISA. Gene and protein expression levels were identified by qRT–PCR and Western blot assays, respectively. The interaction among NEAT1, miR‐29a, and NFATc3 was identified by dual‐luciferase reporter and RNA pull‐down assays. In hypoxia‐treated cells, hypoxia markers (HIF‐1α and HIF‐2α), cytokines (TNF‐α, IL‐1β, and IL‐6) and fibrotic markers (α‐SMA, collagen I and collagen III) were significantly enhanced. Consistently, the expression levels of NEAT1 and NFATc3 were increased, but miR‐29a was decreased in hypoxia‐stimulated cells. Knockdown of NEAT1 significantly decreased cell apoptosis and the releases of TNF‐α, IL‐1β, and IL‐6 as well as reduced the levels of α‐SMA, collagen I, and collagen III. Moreover, NEAT1 positively regulated NFATc3 expression by directly targeting miR‐29a. Functional experiments showed that the anti‐apoptotic, anti‐inflammatory, and anti‐fibrotic effects mediated by NETA1 silencing were impeded by miR‐29a inhibition or NFATc3 overexpression in hypoxia‐stimulated HPAEpic and A549 cells. Collectively, these data demonstrated that NEAT1 knockdown inhibited hypoxia‐induced cell apoptosis, inflammation, and fibrosis by targeting the miR‐29a/NFATc3 axis in PF, suggesting that NEAT1 might be a potential therapeutic target for relieving PF progression. [ABSTRACT FROM AUTHOR]

Introduction: The microRNAs are molecules which have important biologic role and play key point in cancers. The aim of present study was to determine the miR-21, miR-24, and miR-29a expression in serum of patients with oral squamous cell carcinoma.Materials and Methods: Blood samples were obtained from 40 patients (20 in cases and 20 in control group) to determine the miR-21, miR-24, and miR-29a expressions by using real-time PCR and ΔCT.Results: Mean miR-29a was -2.28 ± 2.15 and 5.61 ± 2.38 in case and control groups, respectively. The miR-21 was 6.90 ± 3.86 and -0.88 ± 2.31 in case and control groups, respectively. According to the results, miR-24 was 2.13 ± 2.89 and -0.35 ± 2.44 in case and control, respectively. A significant difference was observed on miR-21, miR-24, and miR-29a between two groups (P < .05). The results obtained by t test showed miR-21 and miR-24 were higher and miR-29a was lower in plasma of oral squamous cell carcinoma patients and this differences were significant (P < .05).Conclusion: These results suggested miR-21, miR-24, and miR-29a in serum of patients with oral squamous cell carcinoma comparing with normal group can be used as potent markers for carcinoma detection and also may be a potentially therapeutic approach in the future. More longitudinal studies with larger samples are necessary to confirm these findings. [ABSTRACT FROM AUTHOR]

Myeloid‐derived suppressor cells (MDSCs) play a pivotal role in mediating the formation of an immunosuppressive environment and assisting tumors in evading the host immune response. However, the mechanism through which tumors manipulate the differentiation and function of MDSCs remains unclear. Here, we report that hypoxia‐induced glioma cells can stimulate the differentiation of functional MDSCs by transferring exosomal miR‐29a and miR‐92a to MDSCs. Our results showed that glioma‐derived exosomes (GEXs) can enhance the differentiation of functional MDSCs both in vitro and in vivo, and hypoxia‐induced GEXs (H‐GEXs) demonstrated a stronger MDSCs induction ability than did normoxia‐induced GEXs (N‐GEXs). A subsequent miRNA sequencing analysis of N‐GEXs and H‐GEXs revealed that hypoxia‐induced exosomal miR‐29a and miR‐92a expression induced the propagation of MDSCs. miR‐29a and miR‐92a activated the proliferation and function of MDSCs by targeting high‐mobility group box transcription factor 1 (Hbp1) and protein kinase cAMP‐dependent type I regulatory subunit alpha (Prkar1a), respectively. Altogether, the results of our study provide new insights into the role of glioma exosomal miRNAs in mediating the formation of immunosuppressive microenvironments in tumors and elucidate the underlying exosomal miR‐29a/miR‐92a‐based regulatory mechanism responsible for the modulation of functional MDSC induction. What's new? Myeloid derived suppressor cells (MDSC) suppress the immune system, reducing the effectiveness of immunotherapy in various cancers. These authors investigated how hypoxia promotes the immunosuppressive activity of MDSCs. Glioma cells, they found, use exosomes to transport miRNAs to MDSC progenitor cells, stimulating their differentiation. Hypoxia‐induced exosomes exerted a more powerful effect on MDSC proliferation than normoxia‐induced exosomes. The miRNAs induced MDSCs by targeting two genes, Hbp1 and Prkar1a. miRNA silencing of Hbp1 induced the cell cycle progression of MDSCs. This is the first study to demonstrate a mechanism by which glioma cells stimulate MDSC expansion. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive gastrointestinal tumors, with an overall 5‐year survival rate less than 8%. The dismal prognosis is mainly due to aggressive potential for metastasis. Hence, there is an urgent need for a better understanding of the molecular mechanisms underlying pancreatic cancer invasion and metastasis to improve the unfavorable overall survival (OS) of PDAC patients. In this study, we identified microRNA‐29a (miR‐29a) as an important tumor suppressor, which was downregulated in PDAC tissues. Moreover, miR‐29a counteracted MUC16‐mediated migration and invasion. In the pancreatic cancer cells, MUC16 upregulated c‐Myc expression, which enhanced c‐Myc binding to E‐box in the miR‐29a promoter and inhibited miR‐29a transcription. Thus, miR‐29a was negatively correlated with both MUC16 expression and serum CA125 levels. Furthermore, caveolin 2 (CAV2) was demonstrated to be the target of miR‐29a by bioinformatics and luciferase reporter assays, and high CAV2 expression was responsible for a poor prognosis, especially in the subgroup with normal CA125 levels. Thus, the present study explains why high levels of serum CA125 are correlated with PDAC metastasis, highlighting the predictive value of this marker in PDAC patients. What's new? Cancer antigen 125 (CA125), a peptide epitope of mucin 16, is known as a biomarker of ovarian and pancreatic cancer. Here the authors uncover a suppressive role of a single microRNA, miR‐29a, in mucin 16‐mediated cell migration and invasion and show miR‐29a levels to be negatively correlated with CA125 levels in pancreatic ductal adenocarcinoma. Moreover, miR‐291‐mediated downregulation of caveolin 2, an oncogene usually overexpressed in pancreatic cancers, was significantly associated with a better clinical prognosis, especially in patients with normal CA125 levels, highlighting the potential predictive value of miR‐29a in pancreatic cancer. [ABSTRACT FROM AUTHOR]

Macrophages and oxidized low-density lipoprotein (ox-LDL) have been verified playing vital roles in the pathogenesis of atherosclerosis (AS). Previous studies demonstrated that microRNA-29a (miR-29a) was upregulated in many atherogenic process and cells, thus acting as an important participant in AS. But the detailed regulation mechanism of miR-29a in AS has not been fully understood. In our study, we demonstrated a positive feedback loop of ox-LDL-SRA-miR-29a. Furthermore, we found that YY1 and STAT1 were upregulated in ox-LDL-stimulating macrophages followed by translocation in the nucleus and binding to the transcriptional promoter region of miR-29a, thus leading to the increase of miR-29a expression. In addition, we demonstrated that JAK1/2 signaling was involved in miR-29a upregulation. Finally, we found that miR-29a played important roles in the secretion of proinflammation factors and lipid uptake in macrophages. We uncovered the molecular mechanism and provide novel insights into the function and regulatory network of miR-29a expression regulated by ox-LDL in macrophages. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are small, non-coding RNA species essential for the post-translational regulation of gene expression. Several miRNA have been proposed to contribute to Human immunodeficiency virus-1 (HIV-1) infection establishment, progression and latency. Among them, miR-29a seems to be of particular interest. The aim of this study was to investigate the association between miR-29a expression and immunologic and virologic markers of HIV infection progression in long-term antiretroviral-treated individuals. In a homogenous group of 165 young adults, with chronic HIV infection, parenterally acquired during childhood, the expression level of miR-29a was found to be inversely correlated with HIV viral load and the degree of immunosuppression, expressed by both CD4 cell count and the CD4/CD8 ratio. There was a significant difference in miR-29a expression according to the patient's response to treatment, with the lowest levels expressed by patients with treatment failure, defined as detectable viremia and CD4 < 350 cells/mm3. No significant correlation was found between miRNA level and the nadir CD4 count or zenith HIV viral load. This study establishes the association between miR-29a expression and markers of HIV infection in long-term survivors, treatment-experienced patients, suggesting its potential use as an indicator for the on-treatment disease evolution. J. Med. Virol. 88:2132-2137, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Recent evidence has shown that deregulated expression of members of the micro RNA-29 (miR-29) family may play a critical role in human cancer, including hematological malignancies. However, the roles of miR-29 in the molecular pathophysiology of T-cell acute lymphoblastic leukemia (T- ALL) has not been investigated. Here, we show that lower levels of miR-29a were significantly associated with higher blast counts in the bone marrow and with increased disease-free survival in T- ALL patients. Furthermore, miR-29a levels are extremely reduced in T- ALL cells compared to normal T cells. Microarray analysis following introduction of synthetic miR-29a mimics into Jurkat cells revealed the downregulation of several predicted targets ( CDK6, PXDN, MCL1, PIK3R1, and CXXC6), including targets with roles in active and passive DNA demethylation (such as DNMT3a, DNMT3b, and members of the TET family and TDG). Restoring miR-29a levels in Jurkat and Molt-4 T- ALL cells led to the demethylation of many genes commonly methylated in T- ALL. Overall, our results suggest that reduced miR-29a levels may contribute to the altered epigenetic status of T- ALL, highlighting its relevance in the physiopathology of this disease. [ABSTRACT FROM AUTHOR]

Here, we found that members of the microRNA-29 family ( miR-29a/b/c ; “ miR-29s ”) were significantly reduced in clear cell renal cell carcinoma (ccRCC) tissues, suggesting that they functioned as tumour suppressors. Restoration of all mature members of the miR-29 family inhibited cancer cell proliferation, migration and invasion. LOXL2 was a direct target gene of miR-29s , as shown by genome-wide gene expression analysis and luciferase reporter assay. Overexpressed LOXL2 was confirmed in ccRCC clinical specimens, and silencing of LOXL2 inhibited cancer cell migration and invasion in ccRCC cell lines. Our data demonstrated that the miR-29s-LOXL2 axis contributed to cancer cell migration and invasion in ccRCC. [ABSTRACT FROM AUTHOR]

We previously found that miR-29a was significantly downregulated in Ankylosing spondylitis ( AS) patients, a chronic inflammatory disease associated with bone metabolic disorder, however, the underlying mechanism remains unclear. In this study, we demonstrated that miR-29a regulates tumor necrosis factor- α ( TNF- α) mediated bone loss mainly by targeting DKK1 and GSK3 β, thus activating the Wnt/β-catenin pathway. Our findings may provide new insight into the pathogenesis of the bone metabolism disorder in inflammation environment and provide promising therapeutic target. [ABSTRACT FROM AUTHOR]

Aim: Epithelial-mesenchymal transition (EMT) is a crucial process during cancer invasion and metastasis, which is accompanied by the suppressed expression of E-cadherin initiated by stimuli such as transforming growth factor (TGF)-ß. Recent studies have shown that the epigenetic regulation of E-cadherin could be an alternate mechanism of EMT induction in hepatocellular carcinoma (HCC). miRNA-29a (miR-29a) is involved in the epigenetic regulation of genes by targeting DNA methyltransferases (DNMT), which methylate CpG islands to suppress the transcription of genes. We studied the involvement of miR-29a in TGF-ß-induced EMT in HCC cells. Methods: We treated human HCC cell lines with TGF-β to induce EMT. To investigate DNA methylation in EMT, cells were treated with a methylation inhibitor, 5-Aza-2'- deoxycytidine (5-Aza) and methylation status of CpG islands in the E-cadherin promoter was examined using methylationspecific PCR. Precursor miR-29a (pre-miR-29a) was electroporated to force the expression of miR-29a in HCC cells in order to study the role of miR-29a in EMT. Results: TGF-β transformed HCC cells into a spindle-shaped morphology accompanied by a decrease of E-cadherin with the induction of methylation of its promoter. Pretreatment of the cells with 5-Aza blocked this suppression of E-cadherin, indicating the involvement of DNA methylation. TGF-β increased DNMT3B and DNMT1 and decreased miR-29a expression. The forced expression of miR-29a abrogated the suppression of E-cadherin induced by TGF-β. Conclusion: miR-29a could regulate TGF-β-induced EMT by affecting DNA methylation via the suppression of DNMT. These observations reveal the epigenetic regulation of genes by miRNA as a unique mechanism of EMT in HCC. [ABSTRACT FROM AUTHOR]

Highlights: [•] Saturated fatty acid increases miR-29a and causes insulin resistance in myocytes. [•] miR-29a directly targets IRS-1 3′UTR and represses IRS-1 expression. [•] Ectopic expression of miR-29a impairs insulin signaling and glucose uptake. [•] miR-29a is causally related to the development of insulin resistance by SFA. [Copyright &y& Elsevier]

Embryo implantation is a complex initial step in establishment of a successful pregnancy. Many m RNAs have been shown to be differentially expressed in the rat uterus during embryo implantation. However, the expression profiles of micro RNAs (mi RNAs), a key post-transcriptional regulator of gene expression, in the rat uterus between the pre-receptive and receptive phases are still unknown. Here, an mi RNA microarray was used to examine differential expression of mi RNAs in the rat uterus between the pre-receptive and receptive phases. Twenty-eight mi RNAs were up-regulated and 29 mi RNAs were down-regulated at least twofold during the receptive phase in rat uterus; these results were confirmed by Northern blotting. miR- 29a was only highly expressed in rat uterus during the implantation period, and activation of delayed implantation and artificial decidualization enhanced the miR- 29a level. Further investigation revealed that both the pro-apoptotic factor genes Bak1 and Bmf and the anti-apoptotic factor gene Bcl- w are targets of miR- 29a. There was weak binding between miR- 29a and the 3′ UTR of the anti-apoptotic factor gene Mcl1. Over-expression of miR- 29a inhibited the late apoptosis of endometrial stromal cells, which may be due to the stronger binding capacity between miR- 29a and the 3′ UTR of pro-apoptotic factors than that between miR- 29a and the 3′ UTR of anti-apoptotic factors. Collectively, miR- 29a plays an important role during embryo implantation by regulating both pro-apoptotic and anti-apoptotic factors. miR- 29a may predominantly bind pro-apoptotic factors, leading to inhibition of cell apoptosis. [ABSTRACT FROM AUTHOR]

M. Shioya, S. Obayashi, H. Tabunoki, K. Arima, Y. Saito, T. Ishida and J. Satoh (2010) Neuropathology and Applied Neurobiology 36, 320–330 Aberrant microRNA expression in the brains of neurodegenerative diseases: miR-29a decreased in Alzheimer disease brains targets neurone navigator 3 Aims: MicroRNAs (miRNAs) are small non-coding RNAs that regulate translational repression of target mRNAs. Accumulating evidence indicates that various miRNAs, expressed in a spatially and temporally controlled that manner in the brain plays a key role in neuronal development. However, at present, the pathological implication of aberrant miRNA expression in neurodegenerative events remains largely unknown. To identify miRNAs closely associated with neurodegeneration, we performed miRNA expression profiling of brain tissues of various neurodegenerative diseases. Methods: We initially studied the frontal cortex derived from three amyotrophic lateral sclerosis patients by using a microarray of 723 human miRNAs. This was followed by enlargement of study population with quantitative RT-PCR analysis ( n = 21). Results: By microarray analysis, we identified up-regulation of miR-29a, miR-29b and miR-338-3p in amyotrophic lateral sclerosis brains, but due to a great interindividual variation, we could not validate these results by quantitative RT-PCR. However, we found significant down-regulation of miR-29a in Alzheimer disease (AD) brains. The database search on TargetScan, PicTar and miRBase Target identified neurone navigator 3 (NAV3), a regulator of axon guidance, as a principal target of miR-29a, and actually NAV3 mRNA levels were elevated in AD brains. MiR-29a-mediated down-regulation of NAV3 was verified by the luciferase reporter assay. By immunohistochemistry, NAV3 expression was most evidently enhanced in degenerating pyramidal neurones in the cerebral cortex of AD. Conclusions: These observations suggest the hypothesis that underexpression of miR-29a affects neurodegenerative processes by enhancing neuronal NAV3 expression in AD brains. [ABSTRACT FROM AUTHOR]

Abstract: Deposition of collagen IV in proximal tubule cells (PTCs) plays an important role during diabetic nephropathy, but the mechanism underlying excessive production of collagen IV remains poorly understood. In this study, we examined the miRNA profile of HK-2 cells and found that high glucose/TGF-β1 induced significant down-regulation of miR-29a. We then showed that miR-29a negatively regulated collagen IV by directly targeting the 3′UTRs of col4a1 and col4a2. These results suggest that miR-29a acts as a repressor to fine-tune collagen expression and that the reduction of miR-29a caused by high glucose may increase the risk of excess collagen deposition in PTCs. [Copyright &y& Elsevier]

Alterations in gene expression are central to the malignant phenotype. In this issue, Al-Ahmadi et al elegantly demonstrate that one key mechanism that determines invasiness in breast cancer is likely to be dysregulation of mRNA stability. This is achieved by altered expression of the proteins TTP and HuR, which bind 3′ untranslated region ( UTR) elements in cancer-related genes. The authors link this to the expression of a miRNA, miR-29a, and show that anti- miR-29a treatment can reverse the invasive phenotype in vitro. This further highlights the important roles of mRNA UTRs in malignant transformation, and the importance of investigating post-transcriptional disease mechanisms. Such mechanisms have the potential to provide novel therapeutic targets, as well as being vital to further our understanding of cancer biology. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]