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Nature Communications Jun 2024Coordination of neuronal differentiation with expansion of the neuroepithelial/neural progenitor cell (NEPC/NPC) pool is essential in early brain development. Our in...
Coordination of neuronal differentiation with expansion of the neuroepithelial/neural progenitor cell (NEPC/NPC) pool is essential in early brain development. Our in vitro and in vivo studies identify independent and opposing roles for two neural-specific and differentially expressed non-coding RNAs derived from the same locus: the evolutionarily conserved lncRNA Rncr3 and the embedded microRNA miR124a-1. Rncr3 regulates NEPC/NPC proliferation and controls the biogenesis of miR124a, which determines neuronal differentiation. Rncr3 conserved exons 2/3 are cytosine methylated and bound by methyl-CpG binding protein MeCP2, which restricts expression of miR124a embedded in exon 4 to prevent premature neuronal differentiation, and to orchestrate proper brain growth. MeCP2 directly binds cytosine-methylated Rncr3 through previously unrecognized lysine residues and suppresses miR124a processing by recruiting PTBP1 to block access of DROSHA-DGCR8. Thus, miRNA processing is controlled by lncRNA mC methylation along with the defined mC epitranscriptomic RNA reader protein MeCP2 to coordinate brain development.
Topics: MicroRNAs; Methyl-CpG-Binding Protein 2; Neurogenesis; Animals; Mice; RNA, Long Noncoding; Neural Stem Cells; Brain; Humans; Cell Differentiation; DNA Methylation; Polypyrimidine Tract-Binding Protein; Cell Proliferation; Mice, Inbred C57BL; 5-Methylcytosine; Male; Exons; Neurons; Ribonuclease III
PubMed: 38879605
DOI: 10.1038/s41467-024-49368-w -
BMC Cancer Jun 2024Bladder cancer (BC) is among the most prevalent malignant urothelial tumors globally, yet the prognosis for patients with muscle-invasive bladder cancer (MIBC) remains...
BACKGROUND
Bladder cancer (BC) is among the most prevalent malignant urothelial tumors globally, yet the prognosis for patients with muscle-invasive bladder cancer (MIBC) remains dismal, with a very poor 5-year survival rate. Consequently, identifying more effective and less toxic chemotherapeutic alternatives is critical for enhancing clinical outcomes for BC patients. Isorhapontigenin (ISO), a novel stilbene isolated from a Gnetum found in certain provinces of China, has shown potential as an anticancer agent due to its diverse anticancer activities. Despite its promising profile, the specific anticancer effects of ISO on BC and the underlying mechanisms are still largely unexplored.
METHODS
The anchorage-independent growth, migration and invasion of BC cells were assessed by soft agar and transwell invasion assays, respectively. The RNA levels of SOX2, miR-129 and SNHG1 were quantified by qRT-PCR, while the protein expression levels were validated through Western blotting. Furthermore, methylation-specific PCR was employed to assess the methylation status of the miR-129 promoter. Functional assays utilized siRNA knockdown, plasmid-mediated overexpression, and chemical inhibition approaches.
RESULTS
Our study demonstrated that ISO treatment significantly reduced SNHG1 expression in a dose- and time-dependent manner in BC cells, leading to the inhibition of anchorage-independent growth and invasion in human basal MIBC cells. This effect was accompanied by the downregulation of MMP-2 and MMP-9 and the upregulation of the tumor suppressor PTEN. Further mechanistic investigations revealed that SOX2, a key upstream regulator of SNHG1, played a crucial role in mediating the ISO-induced transcriptional suppression of SNHG1. Additionally, we found that ISO treatment led to a decrease in DNMT3b protein levels, which in turn mediated the hypomethylation of the miR-129 promoter and the subsequent suppression of SOX2 mRNA 3'-UTR activity, highlighting a novel pathway through which ISO exerts its anticancer effects.
CONCLUSIONS
Collectively, our study highlights the critical role of SNHG1 downregulation as well as its upstream DNMT3b/miR-129/SOX2 axis in mediating ISO anticancer activity. These findings not only elucidate the mechanism of action of ISO but also suggest novel targets for BC therapy.
Topics: Humans; Urinary Bladder Neoplasms; RNA, Long Noncoding; Cell Line, Tumor; Stilbenes; Down-Regulation; Gene Expression Regulation, Neoplastic; DNA (Cytosine-5-)-Methyltransferases; DNA Methyltransferase 3B; Neoplasm Invasiveness; Cell Movement; Cell Proliferation; DNA Methylation; MicroRNAs
PubMed: 38879516
DOI: 10.1186/s12885-024-12490-5 -
BMC Complementary Medicine and Therapies Jun 2024This study explored the impact of predicted miRNAs on DNA methyltransferases (DNMTs) and the PODXL gene in Nalm6 cells, revealing the significance of these miRNAs in...
BACKGROUND
This study explored the impact of predicted miRNAs on DNA methyltransferases (DNMTs) and the PODXL gene in Nalm6 cells, revealing the significance of these miRNAs in acute lymphocytic leukemia (ALL).
METHODS
A comprehensive approach was adopted, integrating bioinformatic analyses encompassing protein structure prediction, molecular docking, dynamics, and ADMET profiling, in conjunction with evaluations of gene and miRNA expression patterns. This methodology was employed to elucidate the therapeutic potential of catechin compounds in modulating the activity of DNA methyltransferases (DNMTs) and the PODXL gene.
RESULTS
The findings from our investigation indicate that catechins possess the capability to inhibit DNMT enzymes. This inhibitory effect is associated with the upregulation of microRNAs miR-200c and miR-548 and a concurrent downregulation of PODXL gene expression. These molecular interactions culminate in an augmented apoptotic response within ALL (Nalm6) cells.
CONCLUSION
The study posits that catechins may represent a viable therapeutic avenue for inducing apoptosis in ALL cells. This is achieved through the modulation of epigenetic mechanisms and alterations in gene expression profiles, highlighting the potential of catechins as agents for cancer therapy.
Topics: Catechin; MicroRNAs; Humans; Cell Line, Tumor; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Molecular Docking Simulation; DNA Modification Methylases; Computer Simulation; Apoptosis
PubMed: 38879474
DOI: 10.1186/s12906-024-04521-2 -
BMC Neurology Jun 2024Hypoxia can cause a variety of diseases, including ischemic stroke and neurodegenerative diseases. Within a certain range of partial pressure of oxygen, cells can...
Hypoxia can cause a variety of diseases, including ischemic stroke and neurodegenerative diseases. Within a certain range of partial pressure of oxygen, cells can respond to changes in oxygen. Changes in oxygen concentration beyond a threshold will cause damage or even necrosis of tissues and organs, especially for the central nervous system. Therefore, it is very important to find appropriate measures to alleviate damage. MiRNAs can participate in the regulation of hypoxic responses in various types of cells. MiRNAs are involved in regulating hypoxic responses in many types of tissues by activating the hypoxia-inducible factor (HIF) to affect angiogenesis, glycolysis and other biological processes. By analyzing differentially expressed miRNAs in hypoxia and hypoxia-related studies, as well as the HT22 neuronal cell line under hypoxic stress, we found that the expression of miR-18a was changed in these models. MiR-18a could regulate glucose metabolism in HT22 cells under hypoxic stress by directly regulating the 3'UTR of the Hif1a gene. As a small molecule, miRNAs are easy to be designed into small nucleic acid drugs, so this study can provide a theoretical basis for the research and treatment of nervous system diseases caused by hypoxia.
Topics: MicroRNAs; Glucose; Hypoxia-Inducible Factor 1, alpha Subunit; Hippocampus; Neurons; Animals; Mice; Cell Hypoxia; Cell Line; Humans
PubMed: 38879468
DOI: 10.1186/s12883-024-03717-w -
Behavioural Brain Research Jun 2024Neuroadaptive changes in the hippocampus underlie addictive-like behaviors in humans or animals chronically exposed to cocaine. miR-181a, which is widely expressed in...
Neuroadaptive changes in the hippocampus underlie addictive-like behaviors in humans or animals chronically exposed to cocaine. miR-181a, which is widely expressed in the hippocampus, acts as a regulator for synaptic plasticity, while its role in drug reinstatement is unclear. In this study, we found that miR-181a regulates the reinstatement of cocaine conditioned place preference(CPP), and altered miR-181a expression changes the complexity of hippocampal neurons and the density and morphology of dendritic spines. By using a luciferase gene reporter, we found that miR-181a targets PRKAA1, an upstream molecule in the mTOR pathway. High miR-181a expression reduced the expression of the PRKAA1 mRNA and promoted mTOR activity and the reinstatement of cocaine CPP. These results indicate that miR-181a is involved in neuronal structural plasticity induced by reinstatement of cocaine CPP, possibly through the activation of the mTOR signaling pathway. This study provides new microRNA targets and a theoretical foundation for the prevention of cocaine-induced reinstatement.
PubMed: 38878971
DOI: 10.1016/j.bbr.2024.115097 -
Poultry Science May 2024Mercuric chloride (HgCl) is a nephrotoxic contaminant that is widely present in the environment. Selenium (Se) can effectively antagonize the biological toxicity caused...
Mercuric chloride (HgCl) is a nephrotoxic contaminant that is widely present in the environment. Selenium (Se) can effectively antagonize the biological toxicity caused by heavy metals. Here, in vivo and in vitro models of Se antagonism to HgCl-induced nephrotoxicity in chickens were established, with the aim of exploring the specific mechanism. Morphological observation and kidney function analysis showed that Se alleviated HgCl-induced kidney tissue injury and cytotoxicity. The results showed that ferroptosis was the primary mechanism for the toxicity of HgCl, as indicated by iron overload and lipid peroxidation. On the one hand, Se significantly prevented HgCl-induced iron overload. On the other hand, Se alleviated the intracellular reactive oxygen species (ROS) levels caused by HgCl. Subsequently, we focused on the sources of ROS during HgCl-induced ferroptosis. Mechanically, Se reduced ROS overproduction induced by HgCl through mitochondrial calcium uniporter (MCU)/mitochondrial calcium uptake 1 (MICU1)-mediated mitochondrial calcium ion (Ca) overload. Furthermore, a dual luciferase reporter assay demonstrated that MICU1 was the direct target of miR-202-5p. Overall, Se represses miR-202-5p/MICU1 axis to attenuate HgCl-induced kidney ferroptosis.
PubMed: 38878746
DOI: 10.1016/j.psj.2024.103891 -
Veterinary Parasitology Jun 2024Cryptosporidium parvum is an important zoonotic pathogen that is studied worldwide. MicroRNAs (miRNAs) act as post-transcriptional regulators and may play a key role in...
Cryptosporidium parvum is an important zoonotic pathogen that is studied worldwide. MicroRNAs (miRNAs) act as post-transcriptional regulators and may play a key role in modulating host epithelial responses following Cryptosporidium infection. Our previous study has shown that C. parvum downregulates the expression of miR-181d through the p50-dependent TLRs/NF-κB pathway. However, the mechanism by which miR-181d regulates host cells in response to C. parvum infection remains unclear. The present study found that miR-181d downregulation inhibited cell apoptosis and increased parasite burden in HCT-8 cells after C. parvum infection. Bioinformatics analysis and luciferase reporter assays have shown that BCL2 was a target gene for miR-181d. Moreover, BCL2 overexpression and miR-181d downregulation had similar results. To further investigate the mechanism by which miR-181d regulated HCT-8 cell apoptosis during C. parvum infection, the expression of molecules involved in the intrinsic apoptosis pathway was detected. Bax, caspase-9, and caspase-3 expression was decreased at 4, 8, 12, and 24 hpi and upregulated at 36 and 48 hpi. Interfering with the expression of miR-181d or BCL2 significantly affected the expression of molecules in the intrinsic apoptosis pathway. These data indicated that miR-181d targeted BCL2 to regulate HCT-8 cell apoptosis and parasite burden in response to C. parvum infection via the intrinsic apoptosis pathway. These results allowed us to further understand the regulatory mechanisms of host miRNAs during Cryptosporidium infection, and provided a theoretical foundation for the design and development of anti-cryptosporidiosis drugs.
PubMed: 38878462
DOI: 10.1016/j.vetpar.2024.110237 -
Clinics (Sao Paulo, Brazil) Jun 2024This study aims to elucidate the role of circUSP9X (Circular RNA Ubiquitin Specific Peptidase 9 X-Linked) in the development of venous thrombosis in the lower...
OBJECTIVES
This study aims to elucidate the role of circUSP9X (Circular RNA Ubiquitin Specific Peptidase 9 X-Linked) in the development of venous thrombosis in the lower extremities.
METHODS
An animal model of Deep Vein Thrombosis (DVT) and a hypoxic model of Human Umbilical Vein Endothelial Cells (HUVECs) treated with Cobalt (II) Chloride (CoCl) were developed. The expression levels of circUSP9X, microRNA-148b-3p (miR-148b-3p), and SRC Kinase Signaling Inhibitor 1 (SRCIN1) were quantified using quantitative reverse transcription Polymerase Chain Reaction and Western blot analysis. Cell cytotoxicity, viability, apoptosis, and inflammation in HUVECs were assessed via Lactate Dehydrogenase (LDH) assay, MTT assay, flow cytometry, Enzyme-Linked Immunosorbent Assay, and Western blot, respectively. Hematoxylin and Eosin staining were employed for histopathological examination of the venous tissues in the animal model. The interaction between circUSP9X, miR-148b-3p, and SRCIN1 was further explored through dual-luciferase reporter assays and RNA Immunoprecipitation experiments.
RESULTS
The present findings reveal a significant upregulation of circUSP9X and SRCIN1 and a concurrent downregulation of miR-148b-3p in DVT cases. Knockdown of circUSP9X or overexpression of miR-148b-3p ameliorated CoCl-induced apoptosis in HUVECs, reduced LDH release, enhanced cellular viability, and mitigated inflammation. Conversely, overexpression of circUSP9X intensified CoCl's cytotoxic effects. The effects of manipulating circUSP9X expression were counteracted by the corresponding modulation of miR-148b-3p and SRCIN1 levels. Additionally, circUSP9X knockdown effectively inhibited the formation of DVT in the mouse model. A competitive binding mechanism of circUSP9X for miR-148b-3p, modulating SRCIN1 expression, was identified.
CONCLUSION
circUSP9X promotes the formation of DVT through the regulation of the miR-148b-3p/SRCIN1 axis.
PubMed: 38878321
DOI: 10.1016/j.clinsp.2024.100403 -
Cell Reports Jun 2024Epitranscriptomics represents a further layer of gene expression regulation. Specifically, N6-methyladenosine (m6A) regulates RNA maturation, stability, degradation, and...
Epitranscriptomics represents a further layer of gene expression regulation. Specifically, N6-methyladenosine (m6A) regulates RNA maturation, stability, degradation, and translation. Regarding microRNAs (miRNAs), while it has been reported that m6A impacts their biogenesis, the functional effects on mature miRNAs remain unclear. Here, we show that m6A modification on specific miRNAs weakens their coupling to AGO2, impairs their function on target mRNAs, determines their delivery into extracellular vesicles (EVs), and provides functional information to receiving cells. Mechanistically, the intracellular functional impairment is caused by m6A-mediated inhibition of AGO2/miRNA interaction, the EV loading is favored by m6A-mediated recognition by the RNA-binding protein (RBP) hnRNPA2B1, and the EV-miRNA function in the receiving cell requires their FTO-mediated demethylation. Consequently, cells express specific miRNAs that do not impact endogenous transcripts but provide regulatory information for cell-to-cell communication. This highlights that a further level of complexity should be considered when relating cellular dynamics to specific miRNAs.
PubMed: 38878288
DOI: 10.1016/j.celrep.2024.114369 -
BMC Cancer Jun 2024Circular RNA (circRNAs) have been found to play major roles in the progression of colorectal cancer (CRC). However, the functions of circ_0008345 (transcribed by PTK2)...
BACKGROUND
Circular RNA (circRNAs) have been found to play major roles in the progression of colorectal cancer (CRC). However, the functions of circ_0008345 (transcribed by PTK2) in regulating CRC development remain undefined. In this study, we aimed to explore the roles and underlying mechanisms of circ_0008345 in CRC.
METHODS
RNase R-treated total cellular RNA was used to verify the circular structure of circ_0008345, and a subcellular fractionation assay was performed to detect the subcellular localization of circ_0008345. RNA pull-down and dual-luciferase assays were used to verify the binding relation between microRNA (miR)-182-5p and circ_0008345 and/or CYP1A2. Colony formation assay, EdU, and Transwell assays were performed to detect the biological behavior of CRC cells in vitro, and CRC cells were injected into mice to observe the tumor formation. m6A immunoprecipitation was used to detect the m6A modification of circ_0008345 in CRC cells.
RESULTS
Circ_0008345, upregulated in CRC tissues and cells, was mainly present in the cytoplasm. Circ_0008345 bound to miR-182-5p, and miR-182-5p targeted CYP1A2, an oncogene in CRC. The colony formation, mobility, EdU-positive cell rate in vitro, and tumor growth in mice were inhibited after the knockdown of circ_0008345. However, the suppressing effects of sh-circ_0008345 on CRC and CYP1A2 expression were significantly reversed after further knockdown of miR-182-5p. METTL3 was the m6A modifier mediating circ_0008345 expression, and the suppression of METTL3 reduced the expression of circ_0008345.
CONCLUSIONS
METTL3-dependent m6A methylation upregulated circ_0008345, which blocked the inhibitory effect of miR-182-5p on CYP1A2, thereby exacerbating the malignant phenotype of CRC cells.
Topics: MicroRNAs; Colorectal Neoplasms; RNA, Circular; Humans; Animals; Mice; Methyltransferases; Disease Progression; Cytochrome P-450 CYP1A2; Gene Expression Regulation, Neoplastic; Cell Proliferation; Cell Line, Tumor; Male; Female; Signal Transduction; Mice, Nude
PubMed: 38877514
DOI: 10.1186/s12885-024-12474-5