Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “microRNA expression”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

1,215 records · Page 68Linked to original sources

Novel serum small extracellular vesicle miRNAs with multi-target RCA-CRISPR sensor for liver cancer detection.

BACKGROUND: Detecting liver cancer (LC) remains a significant challenge in clinical practice. Small extracellular vesicle (sEV) miRNAs show promise as non-invasive biomarkers for LC detection, yet their diagnostic potential remains largely unexplored. This study aimed to identify specific sEV miRNA signatures for LC detection and develop a novel synchronized multi-miRNA detection platform to enhance diagnostic efficiency and sensitivity. METHODS: High-throughput sequencing was conducted across four distinct cohorts: normal controls (NC), hepatitis B virus (HBV) patients, liver cirrhosis patients, and LC patients. This sequencing process identified miRNAs with differential expression, followed by RT-qPCR validation in serum sEV miRNAs from LC patients and NC. An innovative detection method, RCA-CRISPR, was introduced, combining rolling circle amplification (RCA) with CRISPR/Cas12a (RCA-CRISPR) for quick and sensitive miRNAs detection. RESULTS: Sequencing results showed a consistent elevation of hsa-miR-203b-5p, hsa-miR-4661-5p, and hsa-miR-219a-2-3p across all cohorts. RT-qPCR validations confirmed significant upregulation of these miRNAs in serum sEVs from LC patients, and the combined three-miRNA panel exhibited high diagnostic accuracy (p = 0.0003; AUC = 0.81). The RCA-CRISPR method demonstrated a detection limit of 3.12 pM for simultaneous multi-target miRNA detection, highlighting its exceptional sensitivity. CONCLUSIONS: Our study identifies hsa-miR-203b-5p, hsa-miR-4661-5p, and hsa-miR-219a-2-3p as promising sEV miRNA biomarkers for LC detection. The developed RCA-CRISPR sensor provides a robust tool for multi-miRNA analysis, potentially advancing non-invasive LC diagnostics. Future validation in larger, prospectively collected cohorts is essential to establish the clinical utility and performance of this biomarker panel and RCA-CRISPR sensor.

MicroRNAs↗

Methods for detecting the HSV-1 LAT anti-apoptosis activity in virus infected tissue culture cells.

Plasmids expressing the herpes simplex virus type 1 (HSV-1) latency-associated transcript (LAT) reduce apoptosis in transient transfection assays in tissue culture. LAT also reduces apoptosis in the context of the virus in trigeminal ganglia of rabbits and mice at approximately 6-7 days post-infection during the switch from acute to latent HSV-1 infection, a time at which LAT is the only abundantly transcribed viral gene. Analysis of LAT's anti-apoptosis function is complicated in tissue culture by the expression of at least five additional viral gene products that can block apoptosis, and by the fact that apoptosis usually occurs in only a fraction of the cells. Here, we present two approaches for detecting LAT's anti-apoptosis activity in the context of the whole virus in tissue culture. Using a combination of serum starvation to both partially synchronize the cells and induce apoptosis, and Hoechst staining to detect chromatin condensation, we found that there was a small window of time post-infection during which Schwann cells infected with the LAT(-) mutant dLAT2903 reproducibly had more apoptotic nuclei than identically treated cells infected with the LAT(+) parental virus HSV-1 strain McKrae. Using serum starvation and/or UV treatment and a method to isolate fragmented DNA away from large chromosomal DNA, we found a similar window of time post-infection during which Neuro2A cells infected with dLAT2903 had increased DNA fragmentation (as judged by a DNA laddering assay) compared to identically treated cells infected with wild type McKrae or the LAT(+) marker rescued dLAT2903R virus. These assays should permit the use of culture assays, rather than labor intensive animal models, to examine LAT's anti-apoptosis activity in the context of the virus in a large number of existing LAT mutant viruses.

Animals↗

An E2F/miR-20a autoregulatory feedback loop.

The E2F family of transcription factors is essential in the regulation of the cell cycle and apoptosis. While the activity of E2F1-3 is tightly controlled by the retinoblastoma family of proteins, the expression of these factors is also regulated at the level of transcription, post-translational modifications and protein stability. Recently, a new level of regulation of E2Fs has been identified, where micro-RNAs (miRNAs) from the mir-17-92 cluster influence the translation of the E2F1 mRNA. We now report that miR-20a, a member of the mir-17-92 cluster, modulates the translation of the E2F2 and E2F3 mRNAs via binding sites in their 3'-untranslated region. We also found that the endogenous E2F1, E2F2, and E2F3 directly bind the promoter of the mir-17-92 cluster activating its transcription, suggesting an autoregulatory feedback loop between E2F factors and miRNAs from the mir-17-92 cluster. Our data also point toward an anti-apoptotic role for miR-20a, since overexpression of this miRNA decreased apoptosis in a prostate cancer cell line, while inhibition of miR-20a by an antisense oligonucleotide resulted in increased cell death after doxorubicin treatment. This anti-apoptotic role of miR-20a may explain some of the oncogenic capacities of the mir-17-92 cluster. Altogether, these results suggest that the autoregulation between E2F1-3 and miR-20a is important for preventing an abnormal accumulation of E2F1-3 and may play a role in the regulation of cellular proliferation and apoptosis.

Cell Death↗

Construction of a herpes simplex virus type 1 mutant with only a three-nucleotide change in the branchpoint region of the latency-associated transcript (LAT) and the stability of its two-kilobase LAT intron.

Previous studies using a eukaryotic expression system indicated that the unusual stability of the latency-associated transcript (LAT) intron was due to its nonconsensus branchpoint sequence (T.-T Wu, Y.-H. Su, T. M. Block, and J. M. Taylor, Virology, 243:140-149, 1998). The present study investigated the role of the branchpoint sequence in the stability of the intron expressed from the herpes simplex virus type 1 (HSV-1) genome and the role of LAT intron stability in the HSV-1 life cycle. A branchpoint mutant called Sy2 and the corresponding rescued viruses, SyRA and SyRB, were constructed. To preserve the coding sequence of the immediate early gene icp0, which overlaps with the branchpoint region of the 2-kb LAT, a 3-nucleotide mutation into the branchpoint region of the 2-kb LAT was introduced, resulting in a branchpoint that is 85% identical to the consensus intron branchpoint sequence of eukaryotic cells. As anticipated, there was a 90- to 96-fold reduction in 2-kb LAT accumulation following productive infection in tissue culture and latent infection in mice with Sy2, as determined by Northern blot analysis. These results clearly suggest that the accumulation of the 2-kb intron in tissue culture and in vivo is, at least in part, due to the nonconsensus branchpoint sequence of the LAT intron. Interestingly, a failure to accumulate LAT was associated with greater progeny production of Sy2 at a low multiplicity of infection (0.01) in tissue culture, but not in mice. However, the ability of mutant Sy2 to reactivate from trigeminal ganglia (TG) derived from latently infected mice was indistinguishable from that of wild-type virus, as assayed in the mouse TG explant reactivation system.

Animals↗

Whole transcriptome sequencing analyses of islets reveal ncRNA regulatory networks underlying impaired insulin secretion and increased β-cell mass in high fat diet-induced diabetes mellitus.

AIM: Our study aims to identify novel non-coding RNA-mRNA regulatory networks associated with β-cell dysfunction and compensatory responses in obesity-related diabetes. METHODS: Glucose metabolism, islet architecture and secretion, and insulin sensitivity were characterized in C57BL/6J mice fed on a 60% high-fat diet (HFD) or control for 24 weeks. Islets were isolated for whole transcriptome sequencing to identify differentially expressed (DE) mRNAs, miRNAs, IncRNAs, and circRNAs. Regulatory networks involving miRNA-mRNA, lncRNA-mRNA, and lncRNA-miRNA-mRNA were constructed and functions were assessed through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. RESULTS: Despite compensatory hyperinsulinemia and a significant increase in β-cell mass with a slow rate of proliferation, HFD mice exhibited impaired glucose tolerance. In isolated islets, insulin secretion in response to glucose and palmitic acid deteriorated after 24 weeks of HFD. Whole transcriptomic sequencing identified a total of 1324 DE mRNAs, 14 DE miRNAs, 179 DE lncRNAs, and 680 DE circRNAs. Our transcriptomic dataset unveiled several core regulatory axes involved in the impaired insulin secretion in HFD mice, such as miR-6948-5p/Cacna1c, miR-6964-3p/Cacna1b, miR-3572-5p/Hk2, miR-3572-5p/Cckar and miR-677-5p/Camk2d. Additionally, proliferative and apoptotic targets, including miR-216a-3p/FKBP5, miR-670-3p/Foxo3, miR-677-5p/RIPK1, miR-802-3p/Smad2 and ENSMUST00000176781/Caspase9 possibly contribute to the increased β-cell mass in HFD islets. Furthermore, competing endogenous RNAs (ceRNA) regulatory network involving 7 DE miRNAs, 15 DE lncRNAs and 38 DE mRNAs might also participate in the development of HFD-induced diabetes. CONCLUSIONS: The comprehensive whole transcriptomic sequencing revealed novel non-coding RNA-mRNA regulatory networks associated with impaired insulin secretion and increased β-cell mass in obesity-related diabetes.

Mice↗

A non-consensus branch point plays an important role in determining the stability of the 2-kb LAT intron during acute and latent infections of herpes simplex virus type-1.

Herpes simplex virus type 1 (HSV-1) establishes lifelong latent infection in sensory neurons of the peripheral nervous system. During HSV latency, the latency-associated transcripts (LATs) are the only viral transcripts abundantly expressed. The most abundant form of LATs is a 2-kb stable intron spliced from a primary transcript (mLAT). It has been previously reported that a non-consensus branch point influences the stability of the intron (in vitro) in cells transfected with plasmid constructs (J. Virol. 71 (1997) 5849; J. Virol. 71 (1997) 4199). However, it is unknown whether this branch point is important in determining LAT stability in vivo (in the context of virus). To study the role of this stable intron in HSV-1 infection, we have constructed a mutant virus KOS-CONS in which the branch point has been mutated to consensus branch point nucleotides. The accumulation of the 2-kb intron in KOS-CONS-infected cells was greatly reduced. The LAT intron was not detectable in KOS-CONS-infected mouse trigeminal ganglia (TG) during acute and latent phase infection by Northern blot analysis. Replication of the KOS-CONS and the wild-type KOS viruses on Vero cells was determined to be similar, as was the level of HSV-1 DNA in mouse trigeminal ganglia during acute and latent phase infection. Using the mouse TG explant model, the reactivation pattern of both viruses was shown to be similar. Our data suggest that the unique branch point plays a significant role in determining the stability of LAT intron in vivo, but that the stability of the intron does not appear to affect HSV-1 replication, the establishment of latency, or viral reactivation.

Acute Disease↗

ceRNA network of lncRNAs and mRNAs in OSF-to-OSCC progression: Diagnostic biomarkers and functional pathways.

BACKGROUND: Oral submucous fibrosis (OSF) is a chronic potentially malignant disorder that can progress to oral squamous cell carcinoma (OSCC). Although dysregulated non-coding RNAs have been implicated in oral carcinogenesis, the competing endogenous RNA (ceRNA)-mediated regulatory mechanisms underlying OSF-to-OSCC progression remain poorly understood. This study aimed to identify candidate regulatory molecules and construct a putative lncRNA-miRNA-mRNA network associated with malignant transformation. METHODS: Publicly available microarray datasets (GSE117973 and GSE125866) were analyzed to identify differentially expressed genes between OSF and OSCC. Differentially expressed transcripts were classified into mRNAs and lncRNAs based on public transcript annotations. Highly correlated lncRNA-mRNA pairs were identified using Pearson correlation analysis and integrated with multiMiR-supported miRNA-mRNA interactions obtained from public databases to construct a putative ceRNA regulatory network. Functional characterization focused on apoptosis, epithelial-mesenchymal transition (EMT), and immune checkpoint-related pathways. Receiver operating characteristic (ROC) analysis was performed to evaluate diagnostic performance, and selected biomarkers were externally validated using The Cancer Genome Atlas (TCGA) OSCC cohort. RESULTS: Integrated transcriptomic analysis identified several dysregulated mRNAs and lncRNAs associated with OSF-to-OSCC progression. Network analysis highlighted TBC1D3B, RREB1, TEAD3, SREBF1, TMEM41B, FOXK2, and KIAA1958 as prominent hub genes within the putative regulatory network. Functional analyses demonstrated significant associations with apoptosis-, EMT-, and immune checkpoint-related genes, suggesting potential involvement in multiple biological processes contributing to malignant transformation. Several hub genes exhibited strong diagnostic performance, with ROC analysis yielding AUC values ranging from 0.891 to 1.000, indicating excellent discrimination between OSF and OSCC samples. External validation using TCGA further supported the relevance of the identified biomarkers in OSCC. CONCLUSIONS: This study provides a comprehensive transcriptomic framework describing putative lncRNA-miRNA-mRNA regulatory interactions associated with OSF progression to OSCC. The identified hub genes and regulatory networks represent candidate biomarkers for early detection and provide a foundation for future mechanistic and experimental validation. As the proposed ceRNA interactions are computationally inferred, further biological validation is required before clinical application.

RNA, Long Noncoding↗

Extracellular vesicle miR-93-5p cargo regulates glomerular endothelial cell damage in Alport syndrome.

Modulation of miRNA expression in glomerular cells is associated with renal disease. Here, we investigated the role of miR-93-5p in mitigating glomerular damage in Alport syndrome and whether the disease-modifying activity of extracellular vesicles from human amniotic fluid stem cells (hAFSC-EVs) is mediated by their miR-93-5p cargo. We identified downregulation of miR-93-5p specifically in glomerular endothelial cells in Alport syndrome along disease progression. Silencing of miR-93-5p in hAFSC-EVs changed the transcriptomic and proteomic profile, regulating EV disease-modifying activity. Compared with naive hAFSC-EVs, silenced hAFSC-EVs did not rescue glomerular endothelial function in vitro and did not restore kidney function in vivo. We established that hAFSC-EVs regulate VEGFR1 and VEGFR2 signaling by miR-93-5p cargo transfer, highlighting that miR-93-5p can restore glomerular endothelial cell biology. Spatial transcriptomics analysis of hAFSC-EV-injected kidneys showed that these EVs can reverse pathways altered during disease progression by stimulating proregenerative processes, specifically in the glomerulus, by regulating miR-93-5p targets. Alteration of glomerular endothelial cell transcriptomics and miR-93-5p targets was also confirmed in biopsies of patients with Alport syndrome using spatial molecular imaging. We demonstrated the critical role of miR-93-5p in glomerular endothelial cells and the capability of hAFSC-EVs to regulate miR-93-5p and its targets in Alport syndrome.

Humans↗

Depletion of human micro-RNA miR-125b reveals that it is critical for the proliferation of differentiated cells but not for the down-regulation of putative targets during differentiation.

Micro-RNAs are small non-coding RNAs that regulate target gene expression post-transcriptionally through base pairing with the target messenger RNA. Functional characterization of micro-RNAs awaits robust experimental methods to knock-down a micro-RNA as well as to assay its function in vivo. In addition to the recently developed method to sequester micro-RNA with 2'-O-methyl antisense oligonucleotide, we report that small interfering RNA against the loop region of a micro-RNA precursor can be used to deplete the micro-RNA. The depletion of miR-125b by this method had a profound effect on the proliferation of adult differentiated cancer cells, and this proliferation defect was rescued by co-transfected mature micro-RNA. This technique has unique advantages over the 2'-O-methyl antisense oligonucleotide and can be used to determine micro-RNA function, assay micro-RNAs in vivo, and identify the contribution of a predicted micro-RNA precursor to the pool of mature micro-RNA in a given cell. miR-125b and let-7 micro-RNAs are induced, whereas their putative targets, lin-28 and lin-41, are decreased during in vitro differentiation of Tera-2 or embryonic stem cells. Experimental increase or decrease of micro-RNA concentrations did not, however, affect the levels of the targets, a finding that is explained by the fact that the down-regulation of the targets appears to be mostly at the transcriptional level in these in vitro differentiation systems. Collectively these results reveal the importance of micro-RNA depletion strategies for directly determining micro-RNA function in vivo.

Base Sequence↗