Genome-wide miRNA Expression Profiling Research Articles

Circulating Exosomal MicroRNA Signature Predicts Peritoneal Metastasis in Patients with Advanced Gastric Cancer.

Despite a radical operation, about half of gastric cancer (GC) patients with advanced GC experience peritoneal metastasis (PM), and the patients with PM have a poor prognosis. However, because staging laparoscopy was a highly invasive procedure for patients, identification of PM using a liquid biopsy can be useful for patients with GC. This study analyzed two genome-wide miRNA expression profiling datasets (GSE164174 and TCGA). The study prioritized biomarkers in pretreatment plasma specimens from clinical training and validation cohorts of patients with GC. The authors developed an integrated exosomal miRNA panel and established a risk-stratification model, which was combined with the miRNA panel and currently used tumor markers (CEA, CA19-9, CA125, and CA72-4 levels). The comprehensive discovery effort identified a four-miRNA panel that robustly predicted the metastasis with excellent accuracy in the TCGA dataset (area under the curve [AUC] 0.86). A circulating exosomal miRNA panel was established successfully with remarkable diagnostic accuracy in the clinical training (AUC 0.85) and validation (AUC 0.86) cohorts. Moreover, the predictive accuracy of the panel was significantly superior to that of conventional clinical factors (P < 0.01), and the risk-stratification model was dramatically superior to the panel and currently used clinical factors for predicting PM (AUC 0.94; univariate: odds ratio [OR] 77.00 [P < 0.01]; multivariate OR 57.71 [P = 0.01]). The novel risk-stratification model for predicting PM has potential for clinical translation as a liquid biopsy assay for patients with GC. The study findings highlight the potential clinical impact of the model for improved selection and management of patients with GC.

Circulating exosomal microRNA signature to predict peritoneal metastasis in patients with advanced gastric cancer.

396 Background: Despite of radical operation, about half of gastric cancer (GC) patients with advanced GC develop peritoneal metastasis (PM) and the patients with PM has poor prognosis. However, because staging laparoscopy was high invasive procedure for the patients, identification of PM by using liquid biopsy can be useful in patients with GC. Methods: We analyzed two genome-wide miRNA expression profiling datasets (GSE164174 and TCGA). We prioritized biomarkers in pretreatment plasma specimens from clinical training and validation cohorts of patients with GC. We developed an integrated exosomal miRNA panel and established a risk-stratification model, which was combined with miRNA panel and currently used tumor markers (CEA, CA19-9, CA125, and CA72-4 levels). Results: Our comprehensive discovery effort identified a 4-miRNA panel that robustly predicted the metastasis, with an excellent accuracy in TCGA dataset (AUC=0.86). We successfully established a circulating exosomal miRNA panel with remarkable diagnostic accuracy in the clinical training (AUC=0.85) and validation (AUC=0.86) cohorts. Moreover, the predictive accuracy of the panel was significantly superior to conventional clinical factors (P&lt;0.01), and the risk-stratification model was dramatically superior to the panel and currently used clinical factors for predicting PM (AUC=0.94, univariate: OR = 77.00, P &lt; 0.01; multivariate: OR = 57.71, P = 0.01). Conclusions: Our novel risk-stratification model for predicting PM has a potential for clinical translation as a liquid biopsy assay in patients with GC. Our findings highlight the potential clinical impact of our model for improved selection and management of patients with this malignancy.

Comprehensive, integrative genomic analysis of microRNA expression profiles in different tissues of two wheat cultivars with different traits.

Wheat is one of the most important food sources on Earth. MicroRNAs (miRNA) play important roles in wheat productivity. To identify wheat miRNAs, we constructed and sequenced sRNA libraries from leaves and roots of two wheat cultivars (RAC875 and Kukri) with many different traits. Given that available miRNA wheat complement in the plant-specific database PmiREN ( https://pmiren.com ) does not include root tissues and root-associated miRNAs might thus be missing, we performed first the prediction of novel miRNAs using the sRNAbench tool. We found a total of 150 putatively novel miRNA genes with expression of both arms from 289 unique mature sequences and nearly 30% of all miRNA reads in roots corresponded to novel miRNAs. In contrast, this figure in leaves dropped to under 3%, confirming the undersampling of roots in the complement of known miRNAs. By using 120 publicly available wheat datasets, 598 Zea mays small RNA libraries, 64 plant species genomes, wheat degradome library, and functional enrichment analysis, a subset of novel miRNAs were confirmed as bona-fide miRNAs. Of the total 605 miRNAs identified in this study inclusive of 316 known miRNAs, 528 miRNAs were shared by both cultivars, 429 miRNAs were shared by both root tissues and 329 miRNAs were shared by both leaf tissues. In addition, 32 miRNAs were specific to Kukri while 45 miRNAs were specific to RAC875. These miRNAs had diverse functions, such as regulation of gene transcription, protein translation, energy metabolism, and cell cycle progression. Our data provide a genome-wide miRNA expression profile in these two wheat cultivars and help functional studies of wheat genomics.

Protecting minors from tobacco products: public interest litigation enables enforcement in China

Primary immune thrombocytopenia (ITP) is an autoimmune bleeding disorder which characterizes with platelet production impairment and platelet destruction increment. CD4⁺CD25⁺<i>Foxp</i>3⁺ Treg cells (Tregs) are involved in the immune pathogenesis of...

Genome-wide miRNA expression profiling in Psathyrostachys huashanica reveals insights into the resistance response to barley yellow dwarf virus-GAV infection

Barley yellow dwarf virus-GAV (BYDV-GAV) is one of the most harmful viruses transmitted by aphids and can cause a severe yield loss on wheat, barley and oat. In previous study, Psathyrostachys huashanica (P. huashanica) was proved to be an effective resistance resource to BYDV-GAV. To investigate how miRNAs regulate gene expressions in defense to viral infection, we analyzed small RNA profiles in P. huashanica infected with BYDV-GAV at 3, 7 and 14 dpi (days post inoculation). Targets of differentially expressed miRNAs were predicted and associated analysis with mRNA sequencing was conducted. A total of 80 miRNAs were identified from 12 libraries, including 45 known miRNAs and 35 novel miRNAs. A series of differentially expressed miRNAs were identified at different infection stages. Gene ontology (GO) enrichment analysis showed that these target genes were enriched in regulation of biological process, response to stimulus, and catalytic activity. KEGG pathway enrichment analysis revealed that these target genes involved in a series of disease resistance-related pathways, including plant hormone signal transduction, and plant-pathogen interaction. The total 28 mRNA-miRNA pairs, including 10 known miRNAs and 4 novel miRNAs, were identified as being involved in viral resistance. RT-qPCR (Real-time quantitative polymerase chain reaction) verification analysis showed that most miRNAs and corresponding predicted target genes showed a negatively regulated pattern. Besides, 5’ RLM-RACE assays were conducted for further validation. To our knowledge, our study is the first to describe miRNAs in P. huashanica and may offer a valuable database for additional miRNA research in other wild-type species relatives to cultivated crops. In addition, this study provides new insights into the underlying resistance molecular mechanisms upon viral infection.

A microRNA-based liquid biopsy signature for the early detection of esophageal squamous cell carcinoma: a retrospective, prospective and multicenter study

BackgroundCurrently, there is no clinically relevant non-invasive biomarker for early detection of esophageal squamous cell carcinoma (ESCC). Herein, we established and evaluated a circulating microRNA (miRNA)-based signature for the early detection of ESCC using a systematic genome-wide miRNA expression profiling analysis.MethodsWe performed miRNA candidate discovery using three ESCC tissue miRNA datasets (n = 108, 238, and 216) and the candidate miRNAs were confirmed in tissue specimens (n = 64) by qRT-PCR. Using a serum training cohort (n = 408), we conducted multivariate logistic regression analysis to develop an ESCC circulating miRNA signature and the signature was subsequently validated in two independent retrospective and two prospective cohorts.ResultsWe identified eighteen initial miRNA candidates from three miRNA expression datasets (n = 108, 238, and 216) and subsequently validated their expression in ESCC tissues. We thereafter confirmed the overexpression of 8 miRNAs (miR-103, miR-106b, miR-151, miR-17, miR-181a, miR-21, miR-25, and miR-93) in serum specimens. Using a serum training cohort, we developed a circulating miRNA signature (AUC:0.83 [95%CI:0.79–0.87]) and the diagnostic performance of the miRNA signature was confirmed in two independent validation cohorts (n = 126, AUC:0.80 [95%CI:0.69–0.91]; and n = 165, AUC:0.89 [95%CI:0.83–0.94]). Finally, we demonstrated the diagnostic performance of the 8-miRNA signature in two prospective cohorts (n = 185, AUC:0.92, [95%CI:0.87–0.96]); and (n = 188, AUC:0.93, [95%CI:0.88–0.97]). Importantly, the 8-miRNA signature was superior to current clinical serological markers in discriminating early stage ESCC patients from healthy controls (p < 0.001).ConclusionsWe have developed a novel and robust circulating miRNA-based signature for early detection of ESCC, which was successfully validated in multiple retrospective and prospective multinational, multicenter cohorts.

Salivary MicroRNA Signature for Diagnosis of Endometriosis.

Background: Endometriosis diagnosis constitutes a considerable economic burden for the healthcare system with diagnostic tools often inconclusive with insufficient accuracy. We sought to analyze the human miRNAome to define a saliva-based diagnostic miRNA signature for endometriosis. Methods: We performed a prospective ENDO-miRNA study involving 200 saliva samples obtained from 200 women with chronic pelvic pain suggestive of endometriosis collected between January and June 2021. The study consisted of two parts: (i) identification of a biomarker based on genome-wide miRNA expression profiling by small RNA sequencing using next-generation sequencing (NGS) and (ii) development of a saliva-based miRNA diagnostic signature according to expression and accuracy profiling using a Random Forest algorithm. Results: Among the 200 patients, 76.5% (n = 153) were diagnosed with endometriosis and 23.5% (n = 47) without (controls). Small RNA-seq of 200 saliva samples yielded ~4642 M raw sequencing reads (from ~13.7 M to ~39.3 M reads/sample). Quantification of the filtered reads and identification of known miRNAs yielded ~190 M sequences that were mapped to 2561 known miRNAs. Of the 2561 known miRNAs, the feature selection with Random Forest algorithm generated after internally cross validation a saliva signature of endometriosis composed of 109 miRNAs. The respective sensitivity, specificity, and AUC for the diagnostic miRNA signature were 96.7%, 100%, and 98.3%. Conclusions: The ENDO-miRNA study is the first prospective study to report a saliva-based diagnostic miRNA signature for endometriosis. This could contribute to improving early diagnosis by means of a non-invasive tool easily available in any healthcare system.

Differential microRNA expression profile in blood of children with Down syndrome suggests a role in immunological dysfunction.

Down syndrome (DS), caused by trisomy of chromosome 21 (HSA21), results in a broad range of phenotypes. However, the determinants contributing to the complex and variable phenotypic expression of DS are still not fully known. Changes in microRNAs (miRNAs), short non-coding RNA molecules that regulate gene expression post-transcriptionally, have been associated with some DS phenotypes. Here, we investigated the genome-wide mature miRNA expression profile in peripheral blood mononuclear cells (PBMCs) of children with DS and controls and identified biological processes and pathways relevant to the DS pathogenesis. The expression of 754 mature miRNAs was profiled in PBMCs from six children with DS and six controls by RT-qPCR using TaqMan® Array Human MicroRNA Cards. Functions and signaling pathways analyses were performed using DIANA-miRPath v.3 and DIANA-microT-CDS software. Children with DS presented six differentially expressed miRNAs (DEmiRs): four overexpressed (miR-378a-3p, miR-130b-5p, miR-942-5p, and miR-424-3p) and two downregulated (miR-452-5p and miR-668-3p). HSA21-derived miRNAs investigated were not found to be differentially expressed between the groups. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed potential target genes involved in biological processes and pathways pertinent to immune response, e.g., toll-like receptors (TLRs) signaling, Hippo, and transforming growth factor β (TGF-β) signaling pathways. These results suggest that altered miRNA expression could be contributing to the well-known immunological dysfunction observed in individuals with DS.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13577-022-00672-x.

Genome-Wide miRNA Expression Profiling of Molecular Subgroups of Peripheral T-cell Lymphoma

Peripheral T-cell lymphoma (PTCL) is a heterogeneous group of non-Hodgkin lymphomas with aggressive clinical behavior. We performed comprehensive miRNA profiling in PTCLs and corresponding normal CD4+ Th1/2 and TFH-like polarized subsets to elucidate the role of miRNAs in T-cell lymphomagenesis. We used nCounter (NanoString Inc) for miRNA profiling and validated using Taqman qRT-PCR (Applied Biosystems, Inc). Normal CD4+ T cells were polarized into effector Th subsets using signature cytokines, and miRNA significance was revealed using functional experiments. Effector Th subsets showed distinct miRNA expression with corresponding transcription factor expression (e.g., BCL6/miR-19b, -106, -30d, -26b, in IL21-polarized; GATA3/miR-155, miR-337 in Th2-polarized; and TBX21/miR-181a, -331-3p in Th1-polarized cells). Integration of miRNA signatures suggested activation of TCR and PI3K signaling in IL21-polarized cells, ERK signaling in Th1-polarized cells, and AKT-mTOR signaling in Th2-polarized cells, validated at protein level. In neoplastic counterparts, distinctive miRNAs were identified and confirmed in an independent cohort. Integrative miRNA-mRNA analysis identified a decrease in target transcript abundance leading to deregulation of sphingolipid and Wnt signaling and epigenetic dysregulation in angioimmunoblastic T-cell lymphoma (AITL), while ERK, MAPK, and cell cycle were identified in PTCL subsets, and decreased target transcript abundance was validated in an independent cohort. Elevated expression of miRNAs (miR-126-3p, miR-145-5p) in AITL was associated with poor clinical outcome. In silico and experimental validation suggest two targets (miR-126→ SIPR2 and miR-145 → ROCK1) resulting in reduced RhoA-GTPase activity and T-B-cell interaction. Unique miRNAs and deregulated oncogenic pathways are associated with PTCL subtypes. Upregulated miRNA-126-3p and miR-145-5p expression regulate RhoA-GTPase and inhibit T-cell migration, crucial for AITL pathobiology.

Parsing the microRNA genetics basis regulating skeletal muscle fiber types and meat quality traits in pigs.

Muscle fibers are closely related to human diseases and livestock meat quality. However, the genetics basis of microRNAs (miRNAs) in regulating muscle fibers is not completely understood. In this study, we constructed the whole genome-wide miRNA expression profiles of porcine fast-twitch muscle [biceps femoris (Bf)] and slow-twitch muscle [soleus (Sol)], and identified hundreds of miRNAs, including four skeletal muscle-highly expressed miRNAs, ssc-miR-378, ssc-let-7f, ssc-miR-26a, and ssc-miR-27b-3p. Moreover, we identified 63 differentially expressed (DE) miRNAs between biceps femoris vs. soleus, which are the key candidate miRNAs regulating the skeletal muscle fiber types. In addition, we found that the expression of DE ssc-miR-499-5p was significantly correlated to the expression of Myoglobin (r=0.6872, P<0.0001) and Myosin heavy chain 7 (MYH7; r=0.5408, P=0.0020), and pH45min (r=0.3806, P=0.0380) and glucose content (r=-0.4382, P=0.0154); while the expression of DE ssc-miR-499-3p was significantly correlated to the expression of Myoglobin (r=0.5340, P=0.0024) and pH45min (r=0.4857, P=0.0065). Taken together, our data established a sound foundation for further studies on the regulatory mechanisms of miRNAs in skeletal muscle fiber conversion and meat quality traits in livestock, and could provide a genetic explanation of the role of miRNAs in human muscular diseases.

MiR-146b-3p regulates proliferation of pancreatic cancer cells with stem cell-like properties by targeting MAP3K10.

Purpose: Cancer stem cells (CSCs) initiate and maintain tumorigenesis due to their unique pluripotency. However, pancreatic stem cell gene signatures are not completely revealed yet. Here, we isolated pancreatic cancer stem cells (P-CSCs) and exploited their distinct genome-wide mRNA and miRNA expression profiles using microarrays.Methods: CD24+ CD44+ ESA+ cells were isolated from two pancreatic xenograft cells by the flow cytometry and identified the stem cell-like properties by the tumor formation, self-renew and chemoresistance. Microarrays and qRT-PCR were used to exploit their distinct Genome-wide mRNA and miRNA expression profiles. The function and candidate target genes of key microRNA were detected after Ectopic restoration in the pancreatic cancer cell lines MIA Paca-2 (CSChigh) and BxPC-3 (CSClow).Results: In this study, we isolated P-CSCs from two xenografts cells. Genome-wide profiling experiments showed 479 genes and 15 microRNAs specifically expressed in the P-CSCs, including genes involved in TGF-β and p53 signaling pathways and particularly miR-146b-3p as the most significantly downregulated miRNA. We confirmed miR-146b-3p as a downregulated signature in pancreatic cancer tissues and cell line MIA Paca-2 (CSChigh) cells. Ectopic restoration of miR-146b-3p expression with pre-miR reduced cell proliferation, induced apoptosis, increased G1 phase and reduced S phase in cell cycle in MIA Paca-2 (CSChigh), but not in BxPC-3 (CSClow). Re-expression of miR-146b-3p with lentivirus significantly inhibited tumorigenicity in vivo in MIA Paca-2, but slightly in BxPC-3. Furthermore, we demonstrated that miR-146b-3p directly targeted MAP3K10 and might activate Hedgehog pathway as well through DYRK2 and GLI2.Conclusions: These results suggest that P-CSCs have distinct gene expression profiles. MiR-146b-3p inhibits proliferation and induced apoptosis in P-CSCs high cells lines by targeting MAP3K10. Targeting P-CSCs specific genes may provide novel strategies for therapeutic purposes.

Identification of Urinary Exosomal miRNAs for the Non-Invasive Diagnosis of Prostate Cancer.

BackgroundNovel and non-invasive biomarkers with higher sensitivity and specificity for the diagnosis of prostate cancer (PCa) is urgently needed. In this study, we used next-generation sequencing (NGS) to characterize the genome-wide exosomal miRNA expression profiling in urine specimens and explored the diagnostic potential of urinary exosomal miRNAs for PCa.MethodsUrinary exosomal microRNA expression profiling was performed by next-generation sequencing (NGS) and then validated by quantitative real-time PCR.ResultsSignificant downregulation of urinary exosomal miR-375 was observed in PCa patients compared with healthy controls, while the expression levels of urinary exosomal miR-451a, miR-486-3p and miR-486-5p were found to be significantly up-regulated in the PCa patients. Furthermore, the expression level of urinary exosomal miR-375 showed a significant correlation with the clinical T-stage and bone metastasis of patients with PCa (P<0.05). Receiver operator characteristic curve demonstrated that the urinary exosomal miR-375, miR-451a, miR-486-3p and miR-486-5p levels can be used to differentiate PCa patients from healthy controls, with area under the curves (AUCs) of 0.788, 0.757, 0.704 and 0.796, respectively. The urinary exosomal miR-375 was found to be superior in discriminating between localized and metastatic PCa with an AUC of 0.806. Moreover, PCa patients can be distinguished from patients with benign prostatic hyperplasia by using a panel combining urinary exosomal miR-375 and miR-451a with an AUC of 0.726.ConclusionThese findings demonstrate that the urinary exosomal miRNAs can serve as novel and non-invasive biomarkers for diagnosing and predicting the progression of PCa.

Identification of a genome-wide serum microRNA expression profile as potential noninvasive biomarkers for chronic kidney disease using next-generation sequencing.

ObjectiveTo identify serum microRNAs (miRNAs) as potential non-invasive biomarkers for patients with chronic kidney disease (CKD).MethodsWe collected serum samples from healthy controls, CKD stage 1 (CKD1), and stage 5 (CKD5) patients with primary glomerulonephritis (GN), screened differentially expressed miRNAs (DEMs) using next-generation sequencing (NGS), and confirmed the sequencing data using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR).ResultsWe identified 20 and 42 DEMs in the CKD1 and CKD5 patients compared with the controls, respectively, and 70 DEMs in the CKD5 compared with the CKD1 patients. The qRT-PCR results showed that miR-483-5p was up-regulated in the CKD1 and CKD5 patients compared with controls (fold change = 2.56 and 18.77, respectively). miR-363-3p was down-regulated in the CKD5 patients compared with the controls and CKD1 patients (fold change = 0.27 and 0.48, respectively).ConclusionWe identified a genome-wide serum miRNA expression profile in CKD patients, and serum miR-483-5p and miR-363-3p may act as potential diagnostic biomarkers for CKD.

Genome-Wide Differential DNA Methylation and miRNA Expression Profiling Reveals Epigenetic Regulatory Mechanisms Underlying Nitrogen-Limitation-Triggered Adaptation and Use Efficiency Enhancement in Allotetraploid Rapeseed.

Improving crop nitrogen (N) limitation adaptation (NLA) is a core approach to enhance N use efficiency (NUE) and reduce N fertilizer application. Rapeseed has a high demand for N nutrients for optimal plant growth and seed production, but it exhibits low NUE. Epigenetic modification, such as DNA methylation and modification from small RNAs, is key to plant adaptive responses to various stresses. However, epigenetic regulatory mechanisms underlying NLA and NUE remain elusive in allotetraploid B. napus. In this study, we identified overaccumulated carbohydrate, and improved primary and lateral roots in rapeseed plants under N limitation, which resulted in decreased plant nitrate concentrations, enhanced root-to-shoot N translocation, and increased NUE. Transcriptomics and RT-qPCR assays revealed that N limitation induced the expression of NRT1.1, NRT1.5, NRT1.7, NRT2.1/NAR2.1, and Gln1;1, and repressed the transcriptional levels of CLCa, NRT1.8, and NIA1. High-resolution whole genome bisulfite sequencing characterized 5094 differentially methylated genes involving ubiquitin-mediated proteolysis, N recycling, and phytohormone metabolism under N limitation. Hypermethylation/hypomethylation in promoter regions or gene bodies of some key N-metabolism genes might be involved in their transcriptional regulation by N limitation. Genome-wide miRNA sequencing identified 224 N limitation-responsive differentially expressed miRNAs regulating leaf development, amino acid metabolism, and plant hormone signal transduction. Furthermore, degradome sequencing and RT-qPCR assays revealed the miR827-NLA pathway regulating limited N-induced leaf senescence as well as the miR171-SCL6 and miR160-ARF17 pathways regulating root growth under N deficiency. Our study provides a comprehensive insight into the epigenetic regulatory mechanisms underlying rapeseed NLA, and it will be helpful for genetic engineering of NUE in crop species through epigenetic modification of some N metabolism-associated genes.

Abstract 257: Whole miRNome profiling in fecal and plasma exosome samples for the diagnosis of colorectal cancer

Abstract Colorectal cancer (CRC) ranks as the second most common non-sex-specific cancer worldwide and the second cause of cancer deaths. Screening programs for CRC based on the fecal immunochemical test (FIT) are effective in average-risk population for the tumor detection but has low sensitivity for the recognition of advanced adenomas. We identified microRNA (miRNA) signatures by next-generation sequencing in fecal samples that could detect patients with adenomas or CRC. The same signatures were also evaluated in plasma extracellular vesicles (EVs) from the same patients. A genome-wide miRNA expression profiling was initially performed in 221 subjects (80 healthy subjects; 43 adenoma patients; 41 individuals with inflammatory bowel disease [IBD]; and 57 CRC) recruited in a cross-sectional study in Italy where stool and plasma samples have been consecutively collected at colonoscopy. Several differentially expressed miRNAs, mostly in stool samples, have been identified both in common or peculiar of specific comparison among the 3 categories of patients vs healthy subjects. Subsequently, a similar profiling has been performed for a set of 24 paired colorectal tumor and adjacent non-tumor samples from the group of CRC patients already samples for stool and plasma. Several miRNAs (n=137) resulted altered in cancer tissues compared to non-tumor; on the other hand, 91 miRNAs resulted altered in stool and only 6 in plasma EVs. Analyzing stool samples from the whole Italian cohort we observed a good overlap of the altered miRNAs observed in tissues (miR-148a-3p, miR-182-5p, miR-143-3p, miR-12136-3p; miR-378a-3p, miR-1290-5p, miR-21-5p, miR-7704-3p). The identified differentially expressed miRNAs in stool and plasma EVs were validated in an independent cohort from the Czech Republic (22 healthy, 19 Inflammation, 21 Adenoma, 34 CRC) with a similar approach. Preliminary results in this independent cohort showed that 19, 12 and 7 miRNAs were differentially expressed when comparing CRC with healthy, CRC and adenoma and inflammation individuals, respectively. In the comparison of CRC versus healthy subjects we observed a good overlap of miRNAs differentially expressed between the Czech and Italian cohorts: 10 miRNAs (miR-148a-3p, miR-1181-3p, miR-1290-5p, miR-4488-3p, miR-1246-3p, let-7i-5p, let-7b-5p, miR-4497-3p, miR-21-5p, miR-149-3p) were significantly altered in the same directions in the 2 cohorts. Moreover, hsa-miR-1290-5p and hsa-miR-4488-3p resulted significantly upregulated when going from healthy, inflammation, adenoma and CRC both in the Italian and in the Czech cohorts. Finally, with the application of a multi-class machine learning approach, we identified a signature of 13 miRNAs whose expression was able to accurately classify (AUC = 0.90) the four classes of subjects in combination with the information of patient age and sex. These results showed that there could be a potential application of the analyses of nucleic acids in stool as adjuvant in non-invasive screening. Citation Format: Sonia Tarallo, Antonio Francavilla, Giulio Ferrero, Francesca Cordero, Gaetano Gallo, Andrew Maltez Thomas, Paolo Manghi, Veronika Vymetalkova, Ludmila Vodickova, Nicola Segata, Pavel Vodicka, Barbara Pardini, Alessio Naccarati. Whole miRNome profiling in fecal and plasma exosome samples for the diagnosis of colorectal cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 257.

Exosomes from patients with major depression cause depressive-like behaviors in mice with involvement of miR-139-5p-regulated neurogenesis.

Exosomal microRNAs (miRNAs) have been suggested to participate in the pathogenesis of neuropsychiatric diseases, but their role in major depressive disorder (MDD) is unknown. We performed a genome-wide miRNA expression profiling of blood-derived exosomes from MDD patients and control subjects and revealed the top differentially expressed exosomal miRNA, i.e. hsa-miR-139-5p (upregulation), had good performance to differentiate between MDD patients and controls. Tail vein injection of blood exosomes isolated from MDD patients into normal mice caused their depressive-like behaviors as determined by the forced swimming, tail suspension, and novelty suppressed feeding tests, and injection of blood exosomes isolated from healthy volunteers into unpredictable mild stress (CUMS)-treated mice alleviated their depressive-like behaviors. CUMS mice also showed significantly increased blood and brain levels of exosomal miR-139-5p. Furthermore, the depressive-like behaviors in CUMS-treated mice were rescued by intranasal injection of miR-139-5p antagomir, suggesting that increased exosomal miR-139-5p levels may mediate stress-induced depression-like behavior in mice. Both exosome treatment and miR-139-5p antagomir treatment increased hippocampal neurogenesis in the CUMS-treated mice, and treatment of exosome from MDD patients decreased hippocampal neurogenesis in the normal mice. The role of miR-139-5p in neurogenesis was validated by in vitro experiments, demonstrating that miR-139-5p is a negative regulator for neural stem cell proliferation and neuronal differentiation. Our findings together suggest that exosomes from patients with major depression caused depressive-like behaviors in mice with involvement of miR-139-5p-regulated neurogenesis. Therefore, exosomal miRNAs are promising targets for the diagnosis and treatment of MDD.

Identification and Validation of MicroRNA Profiles in Fecal Samples for Detection of Colorectal Cancer

Screening for colorectal cancer (CRC) is effective in the population at average risk. The most extended strategy in organized programs involves the fecal immunochemical test, which is limited by low sensitivity for the detection of advanced adenomas (AAs). We aimed to identify microRNA (miRNA) signatures in fecal samples that identify patients with AAs or CRC and might be used in noninvasive screening. Our study comprised 4 stages. In the discovery phase, we performed genome-wide miRNA expression profiling of 124 fresh, paired colorectal tumor and nontumor samples (30 CRC; 32 AAs) from patients in Spain. In the technical validation stage, miRNAs with altered expression levels in tumor vs nontumor tissues were quantified by reverse-transcription polymerase chain reaction in fecal samples from a subset of patients included in the discovery phase (n= 39) and individuals without colorectal neoplasms (controls, n= 39). In the clinical validation stage, the miRNAs found to be most significantly up-regulated by quantitative reverse transcription polymerase chain reaction analysis were measured in an independent set of fecal samples (n= 767) from patients with positive results from fecal immunochemical tests in a CRC screening program. Finally, we developed a model to identify patients with advanced neoplasms (CRCs or AAs) based on their miRNA profiles, using findings from colonoscopy as the reference standard. Among 200 and 324 miRNAs significantly deregulated in CRC and AA tissues, respectively, 7 and 5 of these miRNAs were also found to be deregulated in feces (technical validation). Of them, MIR421, MIR130b-3p, and MIR27a-3p were confirmed to be upregulated in fecal samples from patients with advanced neoplasms. In our model, the combination of fecal level of MIR421, MIR27a-3p, and hemoglobin identified patients with CRC withan area under the curve (AUC) of 0.93, compared with anAUC of 0.67 for fecal hemoglobin concentration alone. We found that increased levels of 2 miRNAs and hemoglobin in feces can identify patients with AAs or CRC more accurately than fecal hemoglobin concentration alone. Assays for these miRNAs might be added to fecal tests for the detection of CRC or AAs.

Plasma miRNAs as biomarkers for endometriosis.

STUDY QUESTIONCan plasma miRNAs be used for the non-invasive diagnosis of endometriosis in infertile women?SUMMARY ANSWERmiRNA-based diagnostic models for endometriosis failed the test of independent validation.WHAT IS KNOWN ALREADYCirculating miRNAs have been described to be differentially expressed in patients with endometriosis compared with women without endometriosis, suggesting that they could be used for the non-invasive diagnosis of endometriosis. However, these studies have shown limited consistency or conflicting results, and no miRNA-based diagnostic test has been validated in an independent patient cohort.STUDY DESIGN, SIZE, DURATIONWe performed genome-wide miRNA expression profiling by small RNA sequencing to identify a set of plasma miRNAs with discriminative potential between patients with and without endometriosis. Expression of this set of miRNAs was confirmed by RT-qPCR. Diagnostic models were built using multivariate logistic regression with stepwise feature selection. In a final step, the models were tested for validation in an independent patient cohort.PARTICIPANTS/MATERIALS, SETTINGS, METHODSPlasma of all patients was available in the biobank of the Leuven Endometriosis Centre of Excellence. Biomarker discovery and model development were performed in a discovery cohort of 120 patients (controls = 38, endometriosis = 82), and models were tested for validation in an independent cohort of 90 patients (controls = 30, endometriosis = 60). RNA was extracted with the miRNeasy Plasma Kit. Genome-wide miRNA expression analysis was done by small RNA sequencing using the NEBNext small RNA library prep kit and the NextSeq 500 System. cDNA synthesis and qPCR were performed using the Qiagen miScript technology.MAIN RESULTS AND THE ROLE OF CHANCEWe identified a set of 42 miRNAs with discriminative power between patients with and without endometriosis based on genome-wide miRNA expression profiling. Expression of 41 miRNAs was confirmed by RT-qPCR, and 3 diagnostic models were built. Only the model for minimal–mild endometriosis (Model 2: hsa-miR-125b-5p, hsa-miR-28-5p and hsa-miR-29a-3p) had diagnostic power above chance performance in the independent validation (AUC = 60%) with an acceptable sensitivity (78%) but poor specificity (37%).LIMITATIONS, REASONS FOR CAUTIONThe diagnostic models were built and tested for validation in two patient cohorts from a single tertiary endometriosis centre. Further validation tests in large cohorts with patients from multiple endometriosis centres are needed.WIDER IMPLICATION OF THE FINDINGSOur study supports a possible biological link between certain miRNAs and endometriosis, but the potential of these miRNAs as clinically useful biomarkers is questionable in women with infertility. Large studies in well-described patient cohorts, with rigorous methodology for miRNA expression analysis, sufficient statistical power and an independent validation step, are necessary to answer the question of whether miRNAs can be used as diagnostics markers for endometriosis.STUDY FUNDING/COMPETING INTEREST(S)The project was funded by a grant from the Research Foundation - Flanders (FWO). A.V., D.F.O. and D.P. are PhD fellows from the FWO. T.D. is vice president and Head of Global Medical Affairs Fertility, Research and Development, Merck KGaA, Darmstadt, Germany. He is also a professor in Reproductive Medicine and Biology at the Department of Development and Regeneration, Group Biomedical Sciences, KU Leuven (University of Leuven), Belgium and an adjunct professor at the Department of Obstetrics and Gynecology in the University of Yale, New Haven, USA. Neither his corporate role nor his academic roles represent a conflict of interest with respect to the work done by him for this study. The other co-authors have no conflict of interest.Trial registration numberNot applicable.

Co-expression analysis reveals dysregulated miRNAs and miRNA-mRNA interactions in the development of contrast-induced acute kidney injury.

The pathogenesis of contrast-induced acute kidney injury (CI-AKI) is incompletely understood. MicroRNAs (miRNAs) are important mediators that normally function via post-transcriptional degradation of target mRNAs. Emerging evidence indicates the appearance of differentially expressed (DE) miRNAs in CI-AKI following the injection of intravenous contrast medium. However, there are differences in the pathological mechanism and incidence of CI-AKI between intravenous and intra-arterial contrast administration. The present study aimed to investigate the critical roles of dysregulated miRNAs and their associated mRNAs in kidney injury following intra-arterial contrast medium exposure. Based on a reliable CI-AKI rat model, we conducted genome-wide miRNA and mRNA expression profiling analysis using deep sequencing. In the study, 36 DE mature miRNAs were identified (fold change > 1.5 and p value < 0.05) in the kidneys of CI-AKI rats (n = 3) compared with that in the controls (n = 3), consisting of 23 up-regulated and 13 down-regulated DE miRNAs. Bioinformatic analysis revealed that wingnut (Wnt), transforming growth factor beta (TGF-β), and 5'-AMP-activated protein kinase (AMPK) signaling pathways were most likely to be modulated by these dysregulated miRNAs. Around 453 dysregulated genes (fold change > 2.0 and p value < 0.05) were identified. Integrated analysis revealed 2037 putative miRNA-mRNA pairs with negative correlations. Among them, 6 DE miRNAs and 13 genes were selected for further quantitative real-time reverse transcription polymerase chain reaction validation (n = 6 for each group), and a good correspondence between the two techniques was observed. In conclusion, the present study provided evidence of miRNA-mRNA interactions in the development of kidney injury following an intra-arterial contrast injection. These findings provide insights into the underlying mechanisms of CI-AKI.

MicroRNA expression profile in Treg cells in the course of primary immune thrombocytopenia

Primary immune thrombocytopenia (ITP) is an autoimmune bleeding disorder which characterizes with platelet production impairment and platelet destruction increment. CD4+CD25+Foxp3+ Treg cells (Tregs) are involved in the immune pathogenesis of...