miRNA Genes Research Articles

Regulatory microRNAs and phasiRNAs of paclitaxel biosynthesis in Taxus chinensis.

Paclitaxel (trade name Taxol) is a rare diterpenoid with anticancer activity isolated from Taxus. At present, paclitaxel is mainly produced by the semi-synthetic method using extract of Taxus tissues as raw materials. The studies of regulatory mechanisms in paclitaxel biosynthesis would promote the production of paclitaxel through tissue/cell culture approaches. Here, we systematically identified 990 transcription factors (TFs), 460 microRNAs (miRNAs), and 160 phased small interfering RNAs (phasiRNAs) in Taxus chinensis to explore their interactions and potential roles in regulation of paclitaxel synthesis. The expression levels of enzyme genes in cone and root were higher than those in leaf and bark. Nearly all enzyme genes in the paclitaxel synthesis pathway were significantly up-regulated after jasmonate treatment, except for GGPPS and CoA Ligase. The expression level of enzyme genes located in the latter steps of the synthesis pathway was significantly higher in female barks than in male. Regulatory TFs were inferred through co-expression network analysis, resulting in the identification of TFs from diverse families including MYB and AP2. Genes with ADP binding and copper ion binding functions were overrepresented in targets of miRNA genes. The miRNA targets were mainly enriched with genes in plant hormone signal transduction, mRNA surveillance pathway, cell cycle and DNA replication. Genes in oxidoreductase activity, protein-disulfide reductase activity were enriched in targets of phasiRNAs. Regulatory networks were further constructed including components of enzyme genes, TFs, miRNAs, and phasiRNAs. The hierarchical regulation of paclitaxel production by miRNAs and phasiRNAs indicates a robust regulation at post-transcriptional level. Our study on transcriptional and posttranscriptional regulation of paclitaxel synthesis provides clues for enhancing paclitaxel production using synthetic biology technology.

Customizing EV-CATCHER to Purify Placental Extracellular Vesicles from Maternal Plasma to Detect Placental Pathologies.

Placenta Accreta Spectrum (PAS) is a life-threatening condition in which placental trophoblastic cells abnormally invade the uterus, often up to the uterine serosa and, in extreme cases, tissues beyond the uterine wall. Currently, there is no clinical assay for the non-invasive detection of PAS, and only ultrasound and MRI can be used for its diagnosis. Considering the subjectivity of visual assessment, the detection of PAS necessitates a high degree of expertise and, in some instances, can lead to its misdiagnosis. In clinical practice, up to 50% of pregnancies with PAS remain undiagnosed until delivery, and it is associated with increased risk of morbidity/mortality. Although many studies have evaluated the potential of fetal biomarkers circulating in maternal blood, very few studies have evaluated the potential of circulating placental extracellular vesicles (EVs) and their miRNA contents for molecular detection of PAS. Thus, to purify placental EVs from maternal blood, we customized our robust ultra-sensitive immuno-purification assay, termed EV-CATCHER, with a monoclonal antibody targeting the membrane Placental Alkaline Phosphatase (PLAP) protein, which is unique to the placenta and present on the surface of placental EVs. Then, as a pilot evaluation, we compared the miRNA expression profiles of placental EVs purified from the maternal plasma of women diagnosed with placenta previa (controls, n = 16); placenta lying low in uterus but not invasive) to those of placental EVs purified from the plasma of women with placenta percreta (cases, n = 16), PAS with the highest level of invasiveness. Our analyses reveal that miRNA profiling of PLAP+ EVs purified from maternal plasma identified 40 differentially expressed miRNAs when comparing these two placental pathologies. Preliminary miRNA pathway enrichment and gene ontology analysis of the top 14 upregulated and top nine downregulated miRNAs in PLAP+ EVs, purified from the plasma of women diagnosed with placenta percreta versus those diagnosed with placenta previa, suggests a potential role in control of cellular invasion and motility that will require further investigation.

A Systematic Review and Meta-Analysis of microRNA Profiling Studies in Chronic Kidney Diseases.

Chronic kidney disease (CKD) represents an increasing health burden. Evidence suggests the importance of miRNA in diagnosing CKD, yet the reports are inconsistent. This study aimed to determine novel miRNA biomarkers and potential therapeutic targets from hypothesis-free miRNA profiling studies in human and murine CKDs. Comprehensive literature searches were conducted on five databases. Subgroup analyses of kidney diseases, sample types, disease stages, and species were conducted. A total of 38 human and 12 murine eligible studies were analyzed using Robust Rank Aggregation (RRA) and vote-counting analyses. Gene set enrichment analyses of miRNA signatures in each kidney disease were conducted using DIANA-miRPath v4.0 and MIENTURNET. As a result, top target genes, Gene Ontology terms, the interaction network between miRNA and target genes, and molecular pathways in each kidney disease were identified. According to vote-counting analysis, 145 miRNAs were dysregulated in human kidney diseases, and 32 were dysregulated in murine CKD models. By RRA, miR-26a-5p was significantly reduced in the kidney tissue of Lupus nephritis (LN), while miR-107 was decreased in LN patients' blood samples. In both species, epithelial-mesenchymal transition, Notch, mTOR signaling, apoptosis, G2/M checkpoint, and hypoxia were the most enriched pathways. These miRNA signatures and their target genes must be validated in large patient cohort studies.

Co-localization and analysis of miR477b with fiber length quantitative trait loci in cotton.

Cotton is an important cash crop for the textile industry. However, the understanding of natural genetic variation of fiber elongation in relation to miRNA is lacking. A miRNA gene (miR477b) was found to co-localize with a previously mapped fiber length (FL) quantitative trait locus (QTL). The miR477b was differentially expressed during fiber elongation between two backcross inbred lines (BILs) differing in FL and its precursor sequences. Bioinformatics and qRT-PCR analysis were further used to analyse the miRNA genes, which could produce mature miR477b. Cotton plants with virus-induced gene silencing (VIGS) constructs to over-express the allele of miR477b from the BIL with longer fibers had significantly longer fibers as compared with negative control plants, while the VIGS plants with suppressed miRNA expression had significantly shorter fibers. The expression level of the target gene (DELLA) and related genes (RDL1 and EXPA1 for DELLA through HOX3 protein) in the two BILs and/or the VIGS plants were generally congruent, as expected. This report represents one of the first comprehensive studies to integrate QTL linkage mapping and physical mapping of small RNAs with both small and mRNA transcriptome analysis, followed by VIGS, to identify candidate small RNA genes affecting the natural variation of fiber elongation in cotton.

MicroRNA-2285f regulates milk fat metabolism by targeting MAP2K2 in bovine mammary epithelial cells.

In this study, Holstein dairy cows raised in Ningxia were selected as the research object. Mammary epithelial cells (BMECs) were extracted from the milk of eight Holstein cows with significantly different milk fat expression rates and transcribed for sequencing. Bioinformatics analysis was used to analyse the correlation of fat milk percentage, and the critical miR-2285f regulating milk fat was screened out. The target gene binding sites were predicted, and 293T cells and mammary epithelial cells were used as miRNA and target gene models for functional verification invitro. The tissue difference of miR-2285f Holstein cows was quantitatively analysed by transfecting miR-2285f mimic and inhibitor. Assay (dual luciferase reporter gene assay) and quantitative real-time PCR (quantitative real-time PCR, qRT-PCR), triglyceride (TAG) detection, oil red O detection of lipid droplets, Western Blot assay, Edu and Flow cytometry, The molecular regulatory effects of miR-2285f and target gene MAP2K2 on milk fat metabolism of Holstein dairy cows were studied. The wild-type vector and mutant vector of map2k2-3'utr were constructed, and double luciferase reporting experiments were conducted to verify that MAP2K2 was one of the target genes of miR-2285f. According to qRT-PCR and Western Blot analysis, miR-2285f mainly regulates the expression of MAP2K2 protein in BMECs at the translation level. Bta-miR-2285f can promote cell proliferation and slow cell apoptosis by regulating MAP2K2. Bta-miR-2285f can promote triglyceride (TAG) and lipid droplet accumulation in mammary epithelial cells by targeting MAP2K2. Bta-miR-2285f can regulate protein levels of fat milk marker gene PPARG by targeting MAP2K2. In conclusion, miR-2285f can target the expression of the MAP2K2 gene, promote the proliferation of dairy mammary epithelial cells, inhibit cell apoptosis and regulate the milk fat metabolism in dairy mammary epithelial cells. The results of this study revealed the function of miR-2285f in regulating the differential expression of fat milk in Holstein dairy cows at the cellular level. They provided a theoretical and experimental basis for analysing the regulation network of milk fat synthesis of Holstein dairy cows and the molecular breeding of dairy cows.

MicroRNA-29 regulates IgE class-switching in B cells and susceptibility to skin inflammation

Abstract MicroRNA (miRNA) gene regulation is vital for the development of B cells. Our group established that the miR-29 family is a regulator of B cell survival and B cell receptor (BCR) signaling. Specifically, we identified PTEN as a direct target of miR-29. Conditional knockout of miR-29 in B cells diminishes cell viability, which is compensated by normalizing Pten expression. In our latest observations, mice with a B-cell-specific miR-29 deletion exhibited an inflammatory skin phenotype, characterized by cutaneous lesions, continuous itching and a 50% survival rate. Pten ablation fails to improve their lifespan. These findings indicate that miR-29 targets other transcripts in B cells apart from Pten. Notable features such as epidermal proliferation and elevated serum IgE levels. We hypothesize the absence of miR-29 in B cells may lead to to atopic dermatitis. Computational analysis predicts miR-29 likely regulates Il4Ra transcript levels, and qPCR supports this prediction. Our in vitro assays demonstrate that B cells deficient in miR-29 exhibit greater IgE class switching when stimulated with IL-4, compared to wild-type counterparts. Additionally, we observed that mice developing inflammatory skin conditions harbor an increased Staphylococcus burden. Therefore, we propose that miR-29 plays a role in the co-regulation of Pten and Il4ra to influence the survival and function of mature B cells and may alter how these cells respond to environmental/microbial antigens.

Small RNA sequencing highlights a potential regulatory network mediated by Gecko miRNA affecting the prognosis of hepatocellular carcinoma.

Gecko has been widely documented in Chinese scientific literature as an anti-tumor agent for various illnesses for thousands of years, and more recently, it has been examined for its anti-tumor effects on several cancers. The effect of Gecko microRNAs (miRNAs) on hepatocellular carcinoma (HCC) has not yet been reported. This study was designed to identify miRNAs in Gecko through small RNA sequencing and utilize bioinformatics techniques to construct a potential regulatory network and explore the possible mechanisms of exogenous miRNAs involved in HCC. RNA was extracted from Gecko tablets, and we screened the Gecko miRNA expression dataset after high-throughput sequencing. Bioinformatics analysis was used to identify novel Gecko and HCC survival-related miRNA-mRNA cross-species regulation networks. miR-100-5p, miR-99a-5p and miR-101-3p were identified as critical for the role of Geckos in HCC. Nine downstream mRNAs (EZH2, KPNA2, LMNB1, LRRC1, MRGBP, SMARCD1, STMN1, SUB1, and UBE2A) were identified as target genes for critical miRNAs. A miRNA-mRNA regulatory network was constructed, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed these key mRNAs might be associated with both the suppression and progression of HCC. The novel network significantly correlated with the abundance of multiple immune cells, as determined with immune infiltration analysis. These findings suggest that Gecko may inhibit progression and exert a therapeutic effect on HCC by targeting critical miRNA-mRNA networks for cross-species regulation. It also provides a reference for future research and development of traditional Chinese medicine (TCM).

Copy number variation analysis identifies MIR9-3 and MIR1299 as novel miRNA candidate genes for CAKUT.

Congenital anomalies of the kidney and urinary tract (CAKUT) represent a frequent cause of pediatric kidney failure. CNVs, as a major class of genomic variations, can also affect miRNA regions. Common CNV corresponding miRNAs (cCNV-miRNAs) are functional variants regulating crucial processes which could affect urinary system development. Thus, we hypothesize that cCNV-miRNAs are associated with CAKUT occurrence and its expressivity. The extraction and filtering of common CNVs, identified in control samples deposited in publicly available databases gnomAD v2.1 and dbVar, were coupled with mapping of miRNA sequences using UCSC Genome Browser. After verification of the mapped miRNAs using referent miRBase V22.1, prioritization of cCNV-miRNA candidates has been performed using bioinformatic annotation and literature research. Genotyping of miRNA gene copy numbers for MIR9-3, MIR511, and MIR1299, was conducted on 221 CAKUT patients and 192 controls using TaqMan™ technology. We observed significantly different MIR9-3 and MIR1299 gene copy number distribution between CAKUT patients and controls (Chi-square, P = 0.006 and P = 0.0002, respectively), while difference of MIR511 copy number distribution showed nominal significance (Chi-square, P = 0.027). The counts of less and more than two of MIR1299 copy numbers were more frequent within CAKUT patients compared to controls (P = 0.01 and P = 0.008, respectively) and also in cohort of patients with anomalies of the urinary tract compared to controls (P = 0.016 and P = 0.003, respectively). Copy number variations of miRNA genes represent a novel avenue in clarification of the inheritance complexity in CAKUT and provide potential evidence about the association of common genetic variation with CAKUT phenotypes.

Goat milk exosomal microRNAs alleviate LPS-induced intestinal inflammation in mice

Intestinal inflammation is a common digestive system disease. Milk-derived exosomes can participate in intercellular communication and transport a variety of bioactive components, and the microRNAs (miRNAs) they carry play important roles in a variety of biological processes in the body. At present, the preventive effect and mechanism of action of goat milk exosomes and their derived miRNAs on intestinal inflammation are still unclear. In this study, the protective effect of goat milk exosomes on LPS-induced intestinal inflammation was investigated using mouse intestinal inflammation model and IEC-6 cell inflammation model. Small RNA sequencing was used to analyze the miRNA expression profile of goat milk exosomes. In this study, C-Exo and M-Exo alleviated intestinal inflammation by reducing the LPS-induced release of proinflammatory cytokines, inhibiting the increase in the NLRP3 protein and the activation of the TLR4/NFκB signaling pathway. C-Exo has a more significant inhibitory effect on them, and better therapeutic efficacy than M-Exo. Notably, the target genes of miRNAs in C-Exo and M-Exo were significantly enriched in immune-related pathways. Furthermore, their derived miR-26a-5p and miR-30a-5p were found to ameliorate the IEC-6 inflammatory response. These findings suggest that miRNAs in goat milk exosomes have the potential to attenuate LPS-induced intestinal inflammation.

Study on the regulation of trophoblast activity by abnormally expressed hsa_circ_0024838/miR-543/HIF1A in patients with gestational diabetes mellitus

IntroductionThis study aimed to screen circRNAs involved in gestational diabetes mellitus (GDM)-related macrosomia. One differentially expressed circRNA (DEC), hsa_circ_0024838, was further tested for its potential role and mechanism in trophoblasts. MethodsDECs in GDM were selected through GSE182737 and GSE194119. The targets were predicted for DECs and microRNAs (miRNAs), to complete the construction of the circRNA-miRNA-gene network. Functional annotation and related biological pathway enrichment analysis were performed on the target genes of miRNAs in the network. Subsequently, the expression levels of hsa_circ_0024838, miR-543, and HIF1A mRNA were identified by real-time quantitative real-time PCR (RT-qPCR) in GDM patients. Trophoblast activity was assessed via CCK-8 assay, apoptosis assay, and Matrigel invasion assay. Finally, interactions between miR-543 and either hsa_circ_0024838 or HIF1A were confirmed using dual-luciferase reporter assays. ResultsA GDM-related circRNA-miRNA-genes interaction network was constructed, consisting of 35 circRNAs, 46 miRNAs, and 122 target genes. Functional enrichment revealed that the enriched pathways were involved in GDM. Hsa_circ_0024838 and HIF1A mRNA expression levels were upregulated in GDM, while miR-543 expression levels were downregulated. A significant positive correlation between hsa_circ_0024838 and newborn weight was observed. Both hsa_circ_0024838 and HIF1A possessed binding sites for miR-543. Overexpressing hsa_circ_0024838 in high-glucose (HG)-cultured trophoblasts can partially reverse HG-induced reduction in trophoblast cell proliferation/migration and increase apoptosis. But this reversal can be negated by co-transfection with miR-543 mimics. The effects of miR-543 can be counteracted by HIF1A. DiscussionHsa_circ_0024838 can regulate the expression of HIF1A by interacting with miR-543. This regulates the HIF1A signaling pathway and enhance vitality in trophoblast cells.

Differential gene expression and miRNA regulatory network in coronary slow flow

Coronary slow flow (CSF) is characterized by slow progression of coronary angiography without epicardial stenosis. The aim of this study was to explore the potential biomarkers and regulatory mechanism for CSF. Peripheral blood mononuclear cells from 3 cases of CSF and 3 healthy controls were collected for high-throughput sequencing of mRNA and miRNA, respectively. The differentially expressed mRNAs (DE-mRNAs) and miRNAs (DE-miRNAs) was identified. A total of 117 DE-mRNAs and 32 DE-miRNAs were obtained and they were mainly enriched in immune and inflammatory responses. Twenty-six DE-mRNAs were the predicted target genes for miRNAs by RAID, and then the regulatory network of 15 miRNAs were constructed. In addition, through the PPI network, we identified the three genes (FPR1, FPR2 and CXCR4) with larger degrees as hub genes. Among them, FPR1 was regulated by hsa-miR-342-3p, hsa-let-7c-5p and hsa-miR-197-3p and participated in the immune response. Finally, we validated the differential expression of hub genes and key miRNAs between 20 CSF and 20 control. Moreover, we found that miR-342-3p has a targeted regulatory relationship with FPR1, and their expression is negatively correlated. Then we established a hypoxia/reoxygenation (H/R) HUVEC model and detected FPR1, cell proliferation and apoptosis. Transfection with miR-342-3p mimics can significantly promote the proliferation of HUVEC under H/R conditions. FPR1 were associated with CSF as a biomarker and may be regulated by miR-342-3p potential biomarkers.

Emerging concepts in alcohol, infection & immunity: A summary of the 2023 alcohol and immunology research interest group (AIRIG) meeting

On December 8th 2023, the annual Alcohol and Immunology Research Interest Group (AIRIG) meeting was held at the University of Colorado Anschutz Medical Campus in Aurora, Colorado. The 2023 meeting focused broadly on how acute and chronic alcohol exposure leads to immune dysregulation, and how this contributes to damage in multiple tissues and organs. These include impaired lung immunity, intestinal dysfunction, autoimmunity, the gut-Central Nervous System (CNS) axis, and end-organ damage. In addition, diverse areas of alcohol research covered multiple pathways behind alcohol-induced cellular dysfunction, including inflammasome activation, changes in miRNA expression, mitochondrial metabolism, gene regulation, and transcriptomics. Finally, the work presented at this meeting highlighted novel biomarkers and therapeutic interventions for patients suffering from alcohol-induced organ damage.

Differential DNA methylation landscape of miRNAs genes in mice liver fibrosis.

Patients with chronic liver disease were found nearly all to have liver fibrosis, which is characterized by excess accumulation of extracellular matrix (ECM) proteins. While ECM accumulation can prevent liver infection and injury, it can destroy normal liver function and architecture. miRNA's own regulation was involved in DNA methylation change. The purpose of this study is to detect DNA methylation landscape of miRNAs genes in mice liver fibrosis tissues. Male mice (10-12 weeks) were injected CCl4 from abdominal cavity to induced liver fibrosis. 850K BeadChips were used to examine DNA methylation change in whole genome. The methylation change of 16 CpG dinucleotides located in promoter regions of 4 miRNA genes were detected by bisulfite sequencing polymerase chain reaction (BSP) to verify chip data accuracy, and these 4 miRNA genes' expressions were detected by RT-qPCR methods. There are 769 differential methylation sites (DMS) in total between fibrotic liver tissue and normal mice liver tissue, which were related with 148 different miRNA genes. Chips array data were confirmed by bisulfite sequencing polymerase chain reaction (R = 0.953; P < 0.01). GO analysis of the target genes of 2 miRNA revealed that protein binding, cytoplasm and chromatin binding activity were commonly enriched; KEGG pathway enrichment analysis displayed that TGF-beta signaling pathway was commonly enriched. The DNA of 148 miRNA genes was found to have methylation change in liver fibrosis tissue. These discoveries in miRNA genes are beneficial to future miRNA function research in liver fibrosis.

Role of Recognition MicroRNAs in Hemaphysalis longicornis and Theileria orientalis Interactions.

Ticks are an important type of pathogen transmission vector, and pathogens not only cause serious harm to livestock but can also infect humans. Because of the roles that ticks play in disease transmission, reducing tick pathogen infectivity has become increasingly important and requires the identification and characterization of these pathogens and their interaction mechanisms. In this study, we determined the miRNA expression profile of Hemaphysalis longicornis infected with Theileria orientalis, predicted the target genes of miRNAs involved in this infection process, and investigated the role of miRNA target recognition during host-pathogen interactions. The results showed that longipain is a target gene of miR-5309, which was differentially expressed at different developmental stages and in various tissues in the control group. However, the miR-5309 level was reduced in the infection group. Analysis of the interaction between miRNA and the target gene showed that miR-5309 negatively regulated the expression of the longipain protein during the infection of H. longicornis with T. orientalis. To verify this inference, we compared longipain with the blocking agent orientalis. In this study, the expression of longipain was upregulated by the inhibition of miR-5309 in ticks, and the ability of the antibody produced by the tick-derived protein to attenuate T. orientalis infection was verified through animal immunity and antigen-antibody binding tests. The results showed that expression of the longipain + GST fusion protein caused the cattle to produce antibodies that could be successfully captured by ticks, and cellular immunity was subsequently activated in the ticks, resulting in a subtractive effect on T. orientalis infection. This research provides ideas for the control of ticks and tickborne diseases and a research basis for studying the mechanism underlying the interaction between ticks and pathogens.

Integrative experimental validation of concomitant miRNAs and transcription factors with differentially expressed genes in acute myocardial infarction.

Identification of concomitant miRNAs and transcription factors (TFs) with differential expression (DEGs) in MI is crucial for understanding holistic gene regulation, identifying key regulators, and precision in biomarker and therapeutic target discovery. We performed a comprehensive analysis using Affymetrix microarray data, advanced bioinformatic tools, and experimental validation to explore potential biomarkers associated with human pathology. The search strategy includes the identification of the GSE83500 dataset, comprising gene expression profiles from aortic wall punch biopsies of MI and non-MI patients, which were used in the present study. The analysis identified nine distinct genes exhibiting DEGs within the realm of MI. miRNA-gene/TF and TF-gene/miRNA regulatory relations were mapped to retrieve interacting hub genes to acquire an MI miRNA-TF co-regulatory network. Furthermore, an animal model of I/R-induced MI confirmed the involved gene based on quantitative RT-PCR and Western blot analysis. The consequences of the bioinformatic tool substantiate the inference regarding the presence of three key hub genes (UBE2N, TMEM106B, and CXADR), a central miRNA (hsa-miR-124-3p), and sixteen TFs. Animal studies support the involvement of predicted genes in the I/R-induced myocardial infarction assessed by RT-PCR and Western blotting. Thus, the final consequences suggest the involvement of promising molecular pathways regulated by TF (p53/NF-κB1), miRNA (hsa-miR-124-3p), and hub gene (UBE2N), which may play a key role in the pathogenesis of MI.

Evaluation of changes in exhausted T lymphocytes and miRNAs expression in the different trimesters of pregnancy in pregnant women.

Throughout the three trimesters of a typical pregnancy, we looked at changes in the expression of miRNAs and exhausted T lymphocytes for this study. Fifty healthy subjects were included in this study. The frequency of exhausted T lymphocytes was measured in isolated PBMCs using flow cytometry. PD-1, TIM-3, and related miRNAs gene expression were assessed using qRT-PCR. The analyses revealed a significant decline in PD-1 and Tim-3 expression in PBMCs from RPL women (p = 0.0003 and p = 0.001, respectively). In addition, PD-1 and TIM-3 expression increased significantly in the 2nd trimester compared with the 1st trimester of healthy pregnant women (p < 0.0001 and p = 0.0002, respectively). PD-1 and TIM-3 expression was down-regulated in the 3rd trimester compared with the 1st and 2nd trimesters. In the present study, we demonstrated that TIM-3+/CD4+, TIM-3+/CD8+, PD-1+/CD4+, and PD-1+/CD8 + exhausted T lymphocytes increased in the circulation of women in the 2nd trimester compared to the 1st and 3rd trimester. In the 3rd trimester, the expression of miR-16-5p increased significantly (p < 0.0001). miR-125a-3p expression was down and upregulated in 2nd (p < 0.0001) and 3rd (p = 0.0007) trimesters compared to 1st trimester, respectively. This study showed a significant elevation of miR-15a-5p in 3rd trimester compared to 1st trimester of pregnant women (p = 0.0002). Expression pattern of PD-1 and TIM3 in exhausted T lymphocytes is different not only between normal pregnant and RPL women but also in different trimesters of pregnancy. So, our results showed the role of these markers in the modulation lymphocytes activity in different stages of pregnancy.

Abstract 5057: microRNA profiling in combination with whole exome sequencing reveals insights into long-term recurrence patterns in chordoma

Abstract While few studies on miRNA profiling in primary chordomas have been published, there is no data on the miRNA landscape of long-term recurrences. Therefore, we performed a miRNA analysis and whole exome sequencing (WES) investigating four patients with multiple recurrences over seven to 16 years and eight patients with non-recurrent tumors (NRTs), conventional, sacral chordomas in order to compare both groups as well as the recurrence cases (RCs) to each other. Our aim was to find typical miRNA patterns distinguishing the recurrences from the NRTs. After histopathological classification, immunohistochemical and morphometric analysis, DNA and miRNA were extracted from formalin-fixed-paraffin-embedded tissue samples and analyzed by WES and Nanostring. The microRNA regulation patterns showed similarities within RCs differing from NRTs. In unsupervised clustering there is a tendency of recurrences clustering apart from the NRTs. The differential expression between cases developing recurrences and NRTs showed highly significant differences between both groups with 32 miRNAs upregulated in the RCs being downregulated in NRTs. The miRNA expression of long-term recurrences of each patient are quite homogenous differing only from their primary tumor. Comparing NRTs with primary tumors that would later develop long-term recurrences showed significant up-regulation of 5 miRNAs in the RCs. This suggests a pivotal molecular difference between singular and long-term recurring chordomas. Our WES analysis confirmed known and revealed possible new driver genes. Recurring tumors had a higher number of mutations classified as pathogenic as well as increased proliferation rates and pleomorphic changes. Recurrences displayed a change in mutational distribution, showing considerably more disturbances in embryonic signaling and our proposed driver genes. Intriguingly, our study found a progress in number of alterations throughout the recurrences most of all affecting chromatin regulation and the new drivers. Less disruption of these pathways in primary cases than in recurrences implies their pivotal role not only in chordoma formation, but also in recurrence evolution. The miRNA alterations were correlated with the genomic differences. Validated affected genes of miRNAs deregulated primarily in the recurrences are involved in those pathways as well. As current targeted therapy options are only sporadically altered in few patients, the progress in number of pathogenic mutations throughout the recurrences as well as the drastic change in miRNA expression could present new research approaches for chordomas with long-term recurrences. Combined clinical and molecular studies of miRNA patterns and genetic alterations could expand the understanding of recurrence development leading to new therapeutic targets inhibiting or delaying recurrence formation. Citation Format: Sarah R. Ullmann, Franziska Karras, Julian Schreier, Kerstin Körber-Ferl, David A. Ullmann, Sabine Franke, Albert Roessner, Dörthe Jechorek. microRNA profiling in combination with whole exome sequencing reveals insights into long-term recurrence patterns in chordoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5057.

Abstract 5686: Identifying rare microRNA risk variants for hereditary breast cancer in African American individuals

Abstract Background: In the United States, breast cancer is the most frequently diagnosed cancer in women. However, African American women tend to have a higher incidence of triple negative breast cancer cases, and an earlier age of disease onset, which are hallmark characteristics of heredity disease. Even with current breakthroughs in breast cancer research, limited research participation from women of African descent has led to a gap in our knowledge of heredity factors that are involved in disease in this population. Furthermore, most breast cancer research has focused on protein coding genes being the culprit of tumorigenesis; however, within the last three decades, research efforts have begun to focus on noncoding RNAs, like microRNAs (miRNAs), as potential factors to promote carcinogenesis. miRNAs are short, noncoding RNA molecules that control gene expression at the post-translational level. miRNAs have several mechanisms to affect gene expression of cellular processes like cell proliferation, apoptosis, invasion, and metastasis. However, the identification and functional role miRNA risk variants play in African American breast cancer is still not fully understood. Methods: 30X whole genome sequencing (WGS) was carried out on an Illumina platform on blood- or saliva-derived DNA from 120 African American breast cancer cases from the Alabama Hereditary Cancer Cohort. The WGS data was analyzed using our established bioinformatics pipeline, which has been adapted from the Genome Analysis Toolkit (GATK) Best Practice Pipeline. Focusing on miRNA variants as risk factors, a miRNA BED file was used to extract regions harboring miRNA genes. The resulting file was then filtered for rare miRNA variants (minor allele frequency &amp;lt;1%) in the African American population based on the Genome Aggregation Database (gnomAD) allele frequency. P-values for variants of interest were calculated using Fisher’s Exact tests. Results: Sequencing data have revealed three rare miRNA variants from our African American cohort that can be potentially associated with breast cancer risk. Upon statistical analysis comparing allele frequencies between the African American general population and the Alabama Hereditary Cancer Cohort, miR7850, miR3145, and miR8074 had p-values 5.21E-05, 3.58E-05, and 2.19E-04, respectively. Conclusions: We have identified three rare miRNA variants that were not previously known to be associated with breast cancer risk. Interestingly, both miR7850 and miR8074 target TP53 and miR3145 targets GREM1 and PALB2, which these targets are known breast cancer susceptibility genes. Understanding the consequence of these variants is important to add to our knowledge of miRNAs that play critical roles in carcinogenesis leading to better treatment strategies. Citation Format: Sheniqua R. Glover, Troy LoBue, Nancy D. Merner. Identifying rare microRNA risk variants for hereditary breast cancer in African American individuals [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5686.

MicroRNA copy number alterations in the malignant transformation of pleomorphic adenoma to carcinoma ex pleomorphic adenoma.

This study used array comparative genomic hybridization to assess copy number alterations (CNAs) involving miRNA genes in pleomorphic adenoma (PA), recurrent pleomorphic adenoma (RPA), residual PA, and carcinoma ex pleomorphic adenoma (CXPA). We analyzed 13 PA, 4 RPA, 29 CXPA, and 14 residual PA using Nexus Copy Number Discovery software. The miRNAs genes affected by CNAs were evaluated based on their expression patterns and subjected to pathway enrichment analysis. Across the groups, we found 216 CNAs affecting 2261 miRNA genes, with 117 in PA, 59 in RPA, 846 in residual PA, and 2555 in CXPA. The chromosome 8 showed higher involvement in altered miRNAs in PAs and CXPA patients. Six miRNA genes were shared among all groups. Additionally, miR-21, miR-455-3p, miR-140, miR-320a, miR-383, miR-598, and miR-486 were prominent CNAs found and is implicated in carcinogenesis of several malignant tumors. These miRNAs regulate critical signaling pathways such as aerobic glycolysis, fatty acid biosynthesis, and cancer-related pathways. This study was the first to explore CNAs in miRNA-encoding genes in the PA-CXPA sequence. The findings suggest the involvement of numerous miRNA genes in CXPA development and progression by regulating oncogenic signaling pathways.

Construction of a prognostic model based on genome-wide methylation analysis of miRNAs for hepatocellular carcinoma.

Aim: Using the methylation level of miRNA genes to develop a prognostic model for patients with hepatocellular carcinoma (HCC). Materials & methods: least absolute shrinkage and selection operator and multivariate Cox regression analyses were performed to develop a prognostic model. One miRNA in the model was selected for verification. Results: A prognostic model was developed using eight miRNAs. The areas under the curve for predicting overall survival at 1, 3and 5years were 0.75, 0.81and 0.81. miR-223 was found to be hypomethylated in 160 HCC tissues, and its methylation level was associated with Barcelona Clinic Liver Cancerstages and the prognosis of patients with HCC. Conclusion: The prognostic model based on miRNA methylation levels has the capability to partially forecast the prognosis of patients with HCC.