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Gastric cancer (GC) poses a significant global health challenge because of its high mortality rate attributed to the late-stage diagnosis and lack of early symptoms. Early cancer diagnostics is crucial for improving the survival rates in GC patients, which emphasizes the importance of identifying GC markers for liquid biopsy. The review discusses a potential use of extracellular vesicle microRNAs (EV miRNAs) as biomarkers for the diagnostics and prognostics of GC. Methods. Original articles on the identification of EV miRNA as GC markers published in the Web of Science and Scopus indexed issues were selected from the PubMed and Google Scholar databases. We focused on the methodological aspects of EV analysis, including the choice of body fluid, methods for EV isolation and validation, and approaches for EV miRNA analysis. Conclusions. Out of 33 found articles, the majority of authors investigated blood-derived extracellular vesicles (EVs); only a few utilized EVs from other body fluids, including tissue-specific local biofluids (washing the tumor growth areas), which may be a promising source of EVs in the context of cancer diagnostics. GC-associated miRNAs identified in different studies using different methods of EV isolation and analysis varied considerably. However, three miRNAs (miR-10b, miR-21, and miR-92a) have been found in several independent studies and shown to be associated with GC in experimental models. Further studies are needed to determine the optimal miRNA marker panel. Another essential step necessary to improve the reliability and reproducibility of EV-based diagnostics is standardization of methodologies for EV handling and analysis of EV miRNA.
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Biomarcadores Tumorais , Vesículas Extracelulares , MicroRNAs , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , MicroRNAs/metabolismo , MicroRNAs/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Biópsia Líquida/métodosRESUMO
Extracellular microRNA (miRNA) expression data generated by different laboratories exhibit heterogeneity, which poses challenges for biologists without bioinformatics expertise. To address this, we introduce ExomiRHub (http://www.biomedical-web.com/exomirhub/), a user-friendly database designed for biologists. This database incorporates 191 human extracellular miRNA expression datasets associated with 112 disease phenotypes, 62 treatments, and 24 genotypes, encompassing 29,198 and 23 sample types. ExomiRHub also integrates 16,012 miRNA transcriptomes of 156 cancer subtypes from The Cancer Genome Atlas. All the data in ExomiRHub were further standardized and curated with annotations. The platform offers 25 analytical functions, including differential expression, co-expression, Weighted Gene Co-Expression Network Analysis (WGCNA), feature selection, and functional enrichment, enabling users to select samples, define groups, and customize parameters for analyses. Moreover, ExomiRHub provides a web service that allows biologists to analyze their uploaded miRNA expression data. Four additional tools were developed to evaluate the functions and targets of miRNAs and miRNA variations. Through ExomiRHub, we identified extracellular miRNA biomarkers associated with angiogenesis for monitoring glioma progression, demonstrating its potential to significantly accelerate the discovery of extracellular miRNA biomarkers.
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High mobility group protein A2 (HMGA2) is widely recognized as a chromatin-binding protein, whose overexpression is observed in nearly all human cancers. It exerts its oncogenic effects by influencing various cellular processes such as the epithelial-mesenchymal transition, cell differentiation, and DNA damage repair. MicroRNA (miRNA) serves as a pivotal gene expression regulator, concurrently modulating multiple genes implicated in cancer progression, including HMGA2. It also serves as a significant biomarker for cancer. Circular RNA (circRNA) plays a crucial role in gene regulation primarily by sequestering miRNAs and impeding their ability to enhance the expression of other genes, including HMGA2. Increasingly, studies have underscored the vital role of miRNA/HMGA2 interactions in cancer. Given the significance of circRNA as an upstream regulatory mediator and the complexity of regulatory mechanisms, we hereby present a comprehensive overview of the pivotal role of circRNAs as upstream regulators of the miRNA//HMGA2 axis in human cancers. This insight may herald a novel direction for future cancer research.
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Studying the intricate relationship between miRNAs and diseases is crucial to prevent and treat miRNA-related disorders. Existing computational methods often overlook the importance of features of different nodes and the propagation of features among heterogeneous nodes. Many prediction models focus only on the feature coding of miRNA and diseases and ignore the importance of feature aggregation. We propose a prediction method via dual-neighbourhood feature aggregation and feature fusion, which uses multiple sources of information, aggregates information on homogeneous and heterogeneous nodes and fuses learned features to predict multiple representations of disease nodes. We constructed similarity networks of multiple homogeneous nodes based on different similarity computation methods respectively, and fused the attention mechanism by using graph convolutional networks to obtain information of different levels of importance. To alleviate the problem of sparse connectivity in the dataset, we built a two-neighbourhood heterogeneous graph neural network model to integrate the homogeneous similarity network into a miRNA-disease heterogeneous network by using known miRNA-disease association information. We used the neighbourhood information associated with the nodes in the network to perform feature aggregation. In addition, we used a feature fusion module to learn the importance of different types of nodes to predict miRNA-disease associations. Our experimental results on the Human microRNA Disease Database (HMDD v3.2) show that the model demonstrates superior performance. This work demonstrates the capability of our model to identify potential miRNAs associated with diseases through a case study of two common cancers.
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Anabolic-androgenic steroids (AAS) abuse is linked to some abnormalities in several tissues including the kidney. However, the precise molecular mediators involved in AAS-induced kidney disorder remain elusive. The main objective of the present study was to investigate the effect of Nandrolone decanoate on kidney injury alone or in combination with moderate exercise and its related mechanisms. Thirty-two male Wistar rats were subdivided randomly into four groups. control (Con), Nandrolone (10 mg/kg)(N), Exercise (Exe), Nandrolone + Exercise (N+Exe). RESULTS: After 6 weeks, nandrolone treatment led to a significant increase in functional parameters such as serum cystatin c, urea, creatinine, albuminuria and Albumin/ creatinine ratio indicating kidney dysfunction. Moreover, nandrolone treatment increased vacuolization, focal inflammation, hemorragia, cast formation fibrosis in the renal tissue of rats. miRNA-146a increased in kidney tissue after nandrolone exposure by using RT-PCR which may be considered idealtheranomiRNAcandidates for diagnosis and treatment. Western blotting indicated that IRAK1, TRAF6, TNF-α, NF-κB, iNOS and TGF-ß protein expressions were considerably elevated in the kidneys of nandrolone treated rats. Moderate exercise could alleviate the renal dysfunction, histological abnormalities and aforementioned proteins. Our findings suggested that nandrolone consumption can cause damage to kidney tissue probably through miRNA-146a targeting IRAK1 and TRAF6 via activation of the NF-κB and TGF-ß pathway. These results provide future lines of research in the identification of theranoMiRNAs related to nandrolone treatment, which can be ameliorated by moderate exercise.
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The clinical benefit of anti-programmed cell death protein 1 (PD-1)-based immunotherapy among patients with microsatellite instable (MSI) endometrial cancer (EC) precedes that of microsatellite stable (MSS) EC, the mechanisms of which have not been fully understood. Circular RNAs (circRNAs) were reported to modulate immune evasion in several types of malignancies, while their roles in the immune regulation in EC remain largely unknown. Here, we conducted circRNA array analysis and mRNA-Sequencing of 10 MSI EC samples and 10 MSS EC samples and identified 1083 differentially expressed circRNAs (DE-circRNAs) and 864 differentially expressed mRNAs, based on which we constructed a circRNA-miRNA-mRNA comprehensive network consisting of 35 DE-circRNAs, 56 predicted miRNAs and 24 differentially expressed mRNAs. Finally, we confirmed hsa_circ_0058230 being positively correlated with CD8+ T cells infiltration, suggesting that it might take a part in anti-tumor immunity in EC.
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Vault RNAs (vtRNAs) are evolutionarily conserved small non-coding RNAs transcribed by RNA polymerase lll. Vault RNAs were initially described as components of the vault particle, but have since been assigned multiple vault-independent functions including regulation of PKR activity, apoptosis, autophagy, lysosome biogenesis, and viral particle trafficking. The full-length transcript has also been described as noncanonical source of miRNAs which are processed in a DICER-dependent manner. As central molecules in vault-dependent and independent processes, vtRNAs have been attributed numerous biological roles including regulation of cell proliferation and survival, response to viral infections, drug resistance, and animal development. Yet, their impact to mammalian physiology remains largely unexplored. To study vault RNAs in vivo, we generated a mouse line with a conditional Vaultrc5 loss of function allele. Because Vaultrc5 is the sole murine vtRNA, this allele enables the characterization of the physiological requirements of this conserved class of small regulatory RNAs in mammals. Using this strain, we show that mice constitutively null for Vaultrc5 are viable and histologically normal but have a slight reduction in platelet counts pointing to a potential role for vtRNAs in hematopoiesis. This work paves the way for further in vivo characterizations of this abundant but mysterious RNA molecule. Specifically, it enables the study of the biological consequences of constitutive or lineage-specific Vaultrc5 deletion and of the physiological requirements for an intact Vaultrc5 during normal hematopoiesis or in response to cellular stresses such as oncogene expression, viral infection, or drug treatment.
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The imperative need for sensitive and precise tools is underscored in cancer diagnostics, with biomarkers playing a pivotal role in facilitating early detection and tumor diagnosis. Despite their classical pathological classification, testicular tumors lack valuable markers, emphasizing the necessity to identify and apply serum tumor markers in clinical management. Unfortunately, existing biomarkers exhibit limited sensitivities and specificities. Recent years have witnessed the discovery of novel RNA molecules, presenting a potential breakthrough as diagnostic tools and promising biomarkers. This report presents compelling evidence supporting the detection of early testicular cancer by applying a set of nine microRNAs (miRNAs), establishing them as valuable serum biomarkers for diagnosis. We developed a standardized serum-based measurement protocol and conducted comprehensive statistical analyses on the dataset to underscore the diagnostic accuracy of the miRNA pool. Notably, with a sensitivity exceeding 93%, miR-21, miR-29a, and miR-106b surpass classical serum tumor markers in the context of testicular cancer. Specifically, these miRNAs are poised to enhance clinical decision-making in testicular cancer detection and hold the potential for assessing tumor growth in monitoring chemotherapy outcomes.
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Biomarcadores Tumorais , MicroRNAs , Neoplasias Testiculares , Masculino , MicroRNAs/sangue , MicroRNAs/genética , Neoplasias Testiculares/sangue , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/genética , Neoplasias Testiculares/patologia , Humanos , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Adulto , Pessoa de Meia-Idade , Metástase Neoplásica , Regulação Neoplásica da Expressão GênicaRESUMO
Lung adenocarcinoma (LUAD) is the most common subtypes of NSCLC. However, the therapeutic effects for LUAD are unsatisfactory at current stage, so it is important to find new molecular targets and therapeutic strategies. circRNAs can regulate the expression of target genes by binding to microRNAs (miRNAs) to form competitive endogenous RNAs (ceRNAs). Therefore, we investigated the functions of circR-4225 in the tumor progression of LUAD and its molecular mechanism in this paper. circR-4225 is up-regulated in LUAD tissues. EIF4A3, a member of the eukaryotic translation initiation factor 4A (EIF4A) family, promotes the expression of circR-4225. circR-4225 acts as a molecular sponge to down-regulate miR-507, which promotes the up-regulation of the expression of its target gene-tumor necrosis factor superfamily member 11 (TNFSF11). Knockdown of circR-4225 in the LUAD cell lines can inhibit cell proliferation and viability, and promote apoptosis of the LUAD cell lines, which can be reverted by inhibiting miR-507 or overexpressing TNFSF11. To sum it up, this study demonstrated that circR-4225 was significantly up-regulated in LUAD tissues, and circR-4225 promoted LUAD progression by sponging miR-507 and up-regulating TNFSF11. This study can provide new molecular targets for early diagnosis and treatment of LUAD.
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Adenocarcinoma de Pulmão , Proliferação de Células , Progressão da Doença , Fator de Iniciação 4A em Eucariotos , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , MicroRNAs , RNA Circular , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Proliferação de Células/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Fator de Iniciação 4A em Eucariotos/metabolismo , Fator de Iniciação 4A em Eucariotos/genética , Linhagem Celular Tumoral , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/metabolismo , Apoptose/genética , Feminino , Masculino , RNA Helicases DEAD-boxRESUMO
Angiogenesis, the formation of new blood vessels from pre-existing ones, is a crucial process in the progression and metastasis of melanoma. Recent research has highlighted the significant role of epigenetic modifications in regulating angiogenesis. This review comprehensively examines the current understanding of how epigenetic mechanisms, including DNA methylation, histone modifications, and non-coding RNAs, influence angiogenic pathways in melanoma. DNA methylation, a key epigenetic modification, can silence angiogenesis inhibitors such as thrombospondin-1 and TIMP3 while promoting pro-angiogenic factors like vascular endothelial growth factor (VEGF). Histone modifications, including methylation and acetylation, also play a pivotal role in regulating the expression of angiogenesis-related genes. For instance, the acetylation of histones H3 and H4 is associated with the upregulation of pro-angiogenic genes, whereas histone methylation patterns can either enhance or repress angiogenic signals, depending on the specific histone mark and context. Non-coding RNAs, particularly microRNAs (miRNAs) further modulate angiogenesis. miRNAs, such as miR-210, have been identified as key regulators, with miR-9 promoting angiogenesis by targeting E-cadherin and enhancing the expression of VEGF. This review also discusses the therapeutic potential of targeting epigenetic modifications to inhibit angiogenesis in melanoma. Epigenetic drugs, such as DNA methyltransferase inhibitors (e.g., 5-azacytidine) and histone deacetylase inhibitors (e.g., Vorinostat), have shown promise in preclinical models by reactivating angiogenesis inhibitors and downregulating pro-angiogenic factors. Moreover, the modulation of miRNAs and lncRNAs presents a novel approach for anti-angiogenic therapy.
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A growing body of evidence indicates that the G protein-coupled bile acid receptor, TGR5, plays a critical role in multiple physiological processes ranging from metabolic disorders to cancers. However, the biological functions of TGR5 in cervical cancer (CC) have not been elucidated. Here, using TGR5 knockout mice, we found that a deficiency of TGR5 leads to greater sensitivity to the progression of cervical inflammation. Activation of TGR5 by its specific ligands significantly attenuated the malignant behavior of CC cells. In addition, we found that TGR5 can negatively modulate the expression of lncRNA HCP5 by blocking its transcription activation when mediated by p65. HCP5 was highly expressed in CC tissues, which was positively correlated with the poor prognosis of CC patients. HCP5 knockdown notably restrained CC cell proliferation, colony formation, and migration in vitro, and inhibited tumor growth in vivo. Furthermore, HCP5 can function as the molecular sponge for miR-139-5p to upregulate DNA damage-induced transcript 4 (DDIT4) in CC cells. Murine xenograft studies demonstrated that TGR5 suppressed the tumor formation of CC cells and downregulated HCP5 and DDIT4 while increasing miR-139-5p in the xenografts. Taken together, these findings, for the first time, indicate that TGR5 inhibits CC progression by regulating the HCP5/miR-139-5p/DDIT4 axis, suggesting that it may represent a novel and potent target for CC treatment.
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Proliferação de Células , Regulação Neoplásica da Expressão Gênica , MicroRNAs , RNA Longo não Codificante , Receptores Acoplados a Proteínas G , Neoplasias do Colo do Útero , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Animais , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/metabolismo , Feminino , Camundongos , Proliferação de Células/genética , Progressão da Doença , Camundongos Knockout , Linhagem Celular Tumoral , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Movimento Celular/genéticaRESUMO
MicroRNAs (miRNAs) are critical post-transcriptional gene regulators and their involvement in sporadic colon cancer (CRC) tumorigenesis has been confirmed. In this study we investigated differences in miRNA expression in microsatellite stable (MSS/EMAST-S), microsatellite unstable marked by high elevated microsatellite alterations at selected tetranucleotide repeats (MSS/EMAST-H), and high microsatellite unstable (MSI-H/EMAST-H) tumor subgroups as well as in tumors with different clinicopathologic characteristics. An RT-qPCR analysis of miRNA expression was carried out on 45 colon cancer and adjacent normal tissue samples (15 of each group). Overall, we found three differentially expressed miRNAs between the subgroups. miR-92a-3p and miR-224-5p were significantly downregulated in MSI-H/EMAST-H tumors in comparison to other subgroups. miR-518c-3p was significantly upregulated in MSS/EMAST-H tumors in comparison to stable and highly unstable tumors. Furthermore, we showed that miR-143-3p and miR-145-5p were downregulated in tumors in comparison to normal tissues in all subgroups. In addition, we showed overexpression of miR-125b-5p in well-differentiated tumors and miR-451a in less advanced tumors. This is the first report on differences in miRNA expression profiles between MSS/EMAST-S, MSS/EMAST-H, and MSI-H/EMAST-H colorectal cancers. Our findings indicate that the miRNA expression signatures differ in CRC subgroups based on their instability status.
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Neoplasias do Colo , Regulação Neoplásica da Expressão Gênica , MicroRNAs , Instabilidade de Microssatélites , Humanos , MicroRNAs/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Perfilação da Expressão Gênica/métodos , Repetições de Microssatélites/genética , Transcriptoma/genéticaRESUMO
MicroRNAs (miRNAs) act as key gene expression regulators, influencing intracellular biological and pathological processes. They are of significant interest in animal genetics as potential biomarkers for animal selection and health. This study aimed to unravel the complex miRNA signature involved in mastitis in in vitro cell culture. For this purpose, we constructed a control and treatment model in ovarian mammary epithelial cells to analyze miRNA responses upon Staphylococcus aureus (S. aureus) stimulation. The high-throughput Illumina Small RNA protocol was employed, generating an average of 7.75 million single-end reads per sample, totaling 46.54 million reads. Standard bioinformatics analysis, including cleaning, filtering, miRNA quantification, and differential expression was performed using the miRbase database as a reference for ovine miRNAs. The results indicated differential expression of 63 miRNAs, including 33 up-regulated and 30 down-regulated compared to the control group. Notably, miR-10a, miR-10b, miR-21, and miR-99a displayed a significant differential expression (p ≤ 0.05) associated to signal transduction, transcriptional pathways, diseases of signal transduction by growth factor receptors and second messengers, MAPK signaling pathway, NF-κB pathway, TNFα, Toll Like Receptor 4 (TLR4) cascade, and breast cancer. This study contributes expanding miRNA databases, especially for sheep miRNAs, and identifies potential miRNA candidates for further study in biomarker identification for mastitis resistance and diagnosis.
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BACKGROUND: Increased prevalence of hepatocellular carcinoma (HCC) remains a global health challenge. HCC chemoresistance is a clinical obstacle for its management. Aberrant miRNA expression is a hallmark for both cancer progression and drug resistance. However, it is unclear which miRNAs are involved in HCC chemoresistance. METHODS: MicroRNA microarray analysis revealed a differential expression profile of microRNAs between the hepatocellular carcinoma HA22T cell line and the HDACi-R cell line, which was validated by quantitative real-time PCR (qRT-PCR). To determine the biological function of miR-342-5p and the mechanism of the microRNA-342-5p/CFL1 axis in hepatocellular carcinoma HDACi resistance, loss- and gain-of-function studies were conducted in vitro. RESULTS: Here we demonstrated the molecular mechanism of histone deacetylase inhibitor (HDACi) resistance in HCC. Differential miRNA expression analysis showed significant down regulation of miR-342-5p in HDACi-R cells than in parental HA22T cells. Mimics of miR-342-5p enhanced apoptosis through upregulation of Bax, cyto-C, cleaved-caspase-3 expressions with concomitant decline in anti-apoptotic protein (Bcl-2) in HDACi-R cells. Although HDACi did not increase cell viability of HDACi-R, overexpression of miR-342-5p decreased cofilin-1 expression, upregulated reactive oxygen species (ROS) mediated apoptosis, and sensitized HDACi-R to HDACi in a dose-dependent manner. CONCLUSION: Our findings demonstrated the critical role of miR-342-5p in HDACi resistance of HCC and that this mechanism might be attributed to miR-342-5p/cofilin-1 regulation.
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Background: MicroRNAs (miRNAs) are small, endogenous non-coding RNA molecules that inhibit gene expression through either destabilization of the target mRNA or translational repression. MiRNAs recognize target sites, most commonly found in the 3'-untranslated regions of cognate mRNAs. This review aims to provide a state-of-the-art overview of the role of miRNAs in the regulation of major blood group antigens such as ABH as well as cancer-specific glycans. Summary: Besides their known roles in the control of developmental processes, proliferation, apoptosis, and carcinogenesis, miRNAs have recently been identified to play a regulatory role during erythropoiesis and blood group antigen expression. Since only little is known about the function of the red cell membrane proteins carrying blood group antigens, it is of great interest to shed light on the regulatory mechanisms of blood group gene expression. Some carrier proteins of blood group antigens are not restricted to red blood cells and are widely expressed in other bodily fluids and tissues and quite a few play a crucial role in tumor cells, as either tumor suppressors or promoters. Key Message: All available data point at a tremendous physiological as well as pathophysiological relevance of miRNAs in context of blood group regulation. Furthermore, miRNAs are involved in the regulation of pleiotropic genetic pathways such as hematopoiesis and tumorigenesis and thus have to be studied in future research on this subject.
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Long non-coding RNAs (lncRNAs) are versatile RNAs that regulate various cellular processes, such as gene regulation, by acting as signals, decoys, guides, and scaffolds. A novel recognized lncRNA, LOXL1-antisense RNA 1 (LOXL1-AS1), is dysregulated in some diseases, including cancer, and acts as an oncogenic lncRNA in many types of cancer cells. Upregulation of LOXL1-AS1 has been involved in proliferation, migration, metastasis, and EMT, as well as inhibiting apoptosis in cancer cells. Most importantly, the malignant promoting activity of LOXL1-AS1 can be mostly mediated by sequestering specific miRNAs and inhibiting their binding to the 3´UTR of their target mRNAs, thereby indirectly regulating gene expression. Additionally, LOXL1-AS1 can decoy transcription factors and proteins and prevent their binding to their regulatory regions, inhibiting their mechanistic activity on the regulation of gene expression and signaling pathways. This review presents the mechanistic pathways of the oncogenic role of LOXL1-AS1 by modulating its target miRNAs and proteins in various cancer cells. Having information about the molecular mechanisms regulated by LOXL1-AS1 in cancer cells can open ways to find out particular prognostic biomarkers, as well as discover novel therapeutic approaches for different types of cancer.
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The accessory proteins Hyponastic-like 1 (HYL1) and Serrated (SE) enhance the precise and efficient processing of miRNAs by Dicer-like 1 (DCL1), which is important for proper miRNA function. However, other factors determining the precision and efficiency of miRNA biogenesis are not well-known. Here, we found that an asymmetric bulge (AB) at the 3' end of miR-5p (produced from the 5' arm of the pre-miRNA) reduced the precision of the second cleavage, whereas an AB at other sites of miR-5p mainly affected the accumulation level of miR-5p in transient expression in Nicotiana benthamiana. In contrast, many ABs in miR-3p (produced from the 3' arm of the pre-miRNA) impose strong negative impact on the processing precision and the accumulation level of miR-5p in N. benthamiana. Arabidopsis DCL1/SE/HYL1 complex-mediated miRNA processing was reconstituted in Saccharomyces cerevisiae to further investigate AB-mediated interference with DCL1 processing. With this system, the positional effect of AB on miRNA processing was tested. The results showed that ABs on the middle of miR-5p have less of an impact on DCL1 cleavage efficiency and precision, whereas those on miR-3p or near the ends of miR-5p strongly reduce DCL1 cleavage activity, precision or both. Studies using the yeast miRNA processing system and transgenic Arabidopsis also revealed the importance of the interaction between the 2-nt 3' overhang of pre-miRNA and the 3' overhang binding pocket (3'BP) on the precision of the second cleavage reaction for many endogenous miRNAs. These findings provide new insights into the mechanism of miRNA biogenesis.
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BACKGROUND: circRNA NFIX has been shown to exist as an oncogene in glioma. But its expression and role in NSCLC (non-small cell lung cancer) are still unclear. This research aimed to discover the expression and function of circRNA NFIX in NSCLC. METHODS: In this research, qRT-PCR was utilized to investigate the expression levels of circRNA NFIX, miRNA-214-3p, and TRIAP1 in NSCLC tissues and cell lines. The binding sites between circRNA NFIX/TRIAP1 and miRNA-214-3p were predicted using the Starbase. These interactions were further validated using a double luciferase reporter assay. Cell proliferation and apoptosis were assessed through MTT and flow cytometry, respectively. The expression of apoptosis-related proteins was measured by western blot assay. RESULTS: miRNA-214-3p could link with circRNA NFIX. circRNA NFIX was upregulated, while miRNA-214-3p was downregulated in NSCLC cell lines and clinical samples. Besides, suppression of circRNA NFIX repressed cell proliferation and induced apoptosis in NSCLC cells by upregulating miRNA-214-3p expression. Besides, the data indicated that TRIAP1 was a target of miRNA-214-3p, and it was negatively regulated by miRNA-214-3p in NSCLC cells. The excessive expression of miRNA-214-3p suppressed NSCLC cell proliferation and increased apoptosis. In addition, overexpression of TRIAP1 significantly reversed the effects on NSCLC cells caused by miRNA-214-3p mimic. CONCLUSION: circRNA NFIX silencing repressed the proliferation of NSCLC cells and induced cell apoptosis by regulating the miR-214-3p/TRIAP1 axis, which was a potential diagnostic and therapeutic target for NSCLC.
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Apoptose , Carcinoma Pulmonar de Células não Pequenas , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , MicroRNAs , Fatores de Transcrição NFI , RNA Circular , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Proliferação de Células/genética , Fatores de Transcrição NFI/genética , Fatores de Transcrição NFI/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Oncogenes/genética , Regulação para Cima , Peptídeos e Proteínas de Sinalização IntracelularRESUMO
Circular RNAs (circRNAs) are single-stranded RNAs that have received much attention in recent years. CircRNAs lack a 5' head and a 3' poly-A tail. The structure of this type of RNAs make them resistant to digestion by exonucleases. CircRNAs are expressed in different cells and have various functions. The function of circRNAs is done by sponging miRNAs, changing gene expression, and protein production. The expression of circRNAs changes in different types of cancers, which causes changes in cell growth, proliferation, differentiation, and apoptosis. Changes in the expression of circRNAs can cause the invasion and progression of tumors. Studies have shown that changes in the expression of circRNAs can be seen in acute lymphoid leukemia (ALL) and chronic lymphoid leukemia (CLL). The conducted studies aim to identify circRNAs whose expression has changed in these leukemias and their more precise function so that these circRNAs can be identified as biomarkers, prediction of patient prognosis, and treatment targets for ALL and CLL patients. In this study, we review the studies conducted on the role and function of circRNAs in ALL and CLL patients. The results of the studies show that there is a possibility of using circRNAs as biomarkers in the identification and treatment of patients in the future.
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Recent studies on the regulatory networks implicated in Alzheimer's disease (AD) evince long non-coding RNAs (lncRNAs) as crucial regulatory players, albeit a poor understanding of the mechanism. Analyzing differential gene expression in the RNA-seq data from the post-mortem AD brain hippocampus, we categorized a list of AD-dysregulated lncRNA transcripts into functionally similar communities based on their k-mer profiles. Using machine-learning-based algorithms, their subcellular localizations were mapped. We further explored the functional relevance of each community through AD-dysregulated miRNA, RNA-binding protein (RBP) interactors, and pathway enrichment analyses. Further investigation of the miRNA-lncRNA and RBP-lncRNA networks from each community revealed the top RBPs, miRNAs, and lncRNAs for each cluster. The experimental validation community yielded ELAVL4 and miR-16-5p as the predominant RBP and miRNA, respectively. Five lncRNAs emerged as the top-ranking candidates from the RBP/miRNA-lncRNA networks. Further analyses of these networks revealed the presence of multiple regulatory triads where the RBP-lncRNA interactions could be augmented by the enhanced miRNA-lncRNA interactions. Our results advance the understanding of the mechanism of lncRNA-mediated AD regulation through their interacting partners and demonstrate how these functionally segregated but overlapping regulatory networks can modulate the disease holistically.