1 1019 106 CIRCRNA-MIRNA CROSS-TALK IN THE TRANSITION FROM PAROXYSMAL TO PERMANENT ATRIAL FIBRILLATION. BACKGROUND: ATRIAL FIBRILLATION (AF) IS THE MOST PREVALENT CARDIAC ARRHYTHMIA IN WESTERN COUNTRIES. THE FACTORS GOVERNING THE PROGRESSION OF AF TO A PERMANENT CHRONIC CONDITION ARE STILL NOT WELL CHARACTERIZED. AMONG EPIGENETIC FACTORS, NON-CODING RNAS (NCRNAS) SUCH AS MIRNAS AND LNCRNAS HAVE BEEN RECENTLY DESCRIBED AS IMPORTANT PLAYERS INVOLVED IN THE AF PROGRESSION. WE HYPOTHESIZE ABOUT THE EXISTENCE OF ADDITIONAL REGULATORY LAYERS IN AF INVOLVING AN INTRICATE CROSS-TALK BETWEEN DIFFERENT NCRNA SPECIES, NAMELY MIRNAS AND CIRCRNAS FOR THE ESTABLISHMENT OF A CHRONIC AF CONDITION. METHODS AND RESULTS: WE HAVE PERFORMED AN UNBIASED STUDY ANALYZING THE EXPRESSION PROFILE FOR MIRNAS AND CIRCRNAS IN LEFT-ATRIAL BIOPSIES FROM PATIENTS WITH PAROXYSMAL AND PERMANENT AF BY RNA-SEQ. THE TRANSITION FROM PAROXYSMAL TO PERMANENT AF IS CHARACTERIZED BY A PATTERN OF DOWN-REGULATED MIRNAS, CONCOMITANT TO THE APPEARANCE OF SPECIFIC CIRCRNA SPECIES. THE ANALYSIS OF THE SPONGING ACTIVITIES OF THE CIRCRNAS EXCLUSIVELY EXPRESSED IN PERMANENT AF SAMPLES, ALLOWED US TO DETERMINE THAT THEY COULD BE RESPONSIBLE FOR THE DOWNREGULATION OF SPECIFIC MIRNAS IN ESTABLISHMENT OF A PERMANENT AF CONDITION. CONCLUSION: SPONGING ACTIVITY OF CIRCRNAS SEQUESTERING SPECIFIC MIRNAS IS AN IMPORTANT FACTOR TO BE CONSIDERED FOR THE DETERMINATION OF THE MOLECULAR MECHANISMS INVOLVED IN AF PROGRESSION. 2019 2 1131 31 COMPREHENSIVE CIRCULAR RNA EXPRESSION PROFILING WITH ASSOCIATED CERNA NETWORK REVEALS THEIR THERAPEUTIC POTENTIAL IN CHOLESTEATOMA. CHOLESTEATOMA IS A CHRONIC DISEASE THAT PATHOLOGICALLY DISPLAYS A BENIGN TUMOR WITH EXCESSIVE SQUAMOUS EPITHELIAL CELL PROLIFERATION IN THE MIDDLE EAR. CLINICALLY, HOWEVER, IT CAN MANIFEST MALIGNANT BEHAVIOR BY DESTROYING ADJACENT TISSUES AND ORGANS. ALTHOUGH PREVIOUS STUDIES HAVE DEMONSTRATED THAT THE PATHOGENESIS OF CHOLESTEATOMA IS CORRELATED WITH EPIGENETIC DYSREGULATION, THE EXACT MECHANISM REMAINS UNCLEAR. CIRCULAR RNAS (CIRCRNAS) HAVE BEEN REVEALED AS BEING ABUNDANTLY EXPRESSED IN VARIOUS ORGANISMS AND HAVE BEEN FOUND TO CONTRIBUTE TO THE REGULATION OF MANY DISEASES. TO DATE, NO REPORTS HAVE ELUCIDATED THEIR EXPRESSION PROFILES AND FUNCTIONS IN CHOLESTEATOMA. IN THE PRESENT STUDY, THE CIRCRNA EXPRESSION PROFILE IN CHOLESTEATOMA WAS EXPLORED FOR THE FIRST TIME BY USING MICROARRAY ANALYSIS. WE OBTAINED A TOTAL OF 355 SIGNIFICANTLY DIFFERENTIALLY EXPRESSED CIRCRNAS IN CHOLESTEATOMA, AMONG WHICH 101 WERE IDENTIFIED TO BE UPREGULATED AND 254 DOWNREGULATED. BY CONSTRUCTING CIRCRNA?LNCRNA?MIRNA?MRNA COMPETING ENDOGENOUS RNA (CERNA) NETWORK, IT WAS DISCOVERED THAT CIRCRNAS MAY FUNCTION AS CERNAS AND CONTRIBUTE TO THE FORMATION OF CHOLESTEATOMA. THESE RESULTS PROVIDE NOVEL INSIGHT INTO THE PATHOGENESIS OF CHOLESTEATOMA AND SUGGEST CIRCRNAS AS POTENTIAL PROMISING THERAPEUTIC TARGETS FOR CHOLESTEATOMA. 2020 3 2909 34 GENE EXPRESSION PROFILING IN FIBROMYALGIA INDICATES AN AUTOIMMUNE ORIGIN OF THE DISEASE AND OPENS NEW AVENUES FOR TARGETED THERAPY. FIBROMYALGIA IS A CHRONIC DISORDER CHARACTERIZED BY WIDESPREAD PAIN AND BY SEVERAL NON-PAIN SYMPTOMS. AUTOIMMUNITY, SMALL FIBER NEUROPATHY AND NEUROINFLAMMATION HAVE BEEN SUGGESTED TO BE INVOLVED IN THE PATHOGENESIS OF THE DISEASE. WE HAVE INVESTIGATED THE GENE EXPRESSION PROFILE IN PERIPHERAL BLOOD MONONUCLEAR CELLS OBTAINED FROM TEN PATIENTS AND TEN HEALTHY SUBJECTS. OF THE 545,500 TRANSCRIPTS ANALYZED, 1673 RESULTED MODULATED IN FIBROMYALGIC PATIENTS. THE MAJORITY OF THESE GENES ARE INVOLVED IN BIOLOGICAL PROCESSES AND PATHWAYS LINKED TO THE CLINICAL MANIFESTATIONS OF THE DISEASE. MOREOVER, GENES INVOLVED IN IMMUNOLOGICAL PATHWAYS CONNECTED TO INTERLEUKIN-17 AND TO TYPE I INTERFERON SIGNATURES WERE ALSO MODULATED, SUGGESTING THAT AUTOIMMUNITY PLAYS A ROLE IN THE DISEASE. WE THEN AIMED AT IDENTIFYING DIFFERENTIALLY EXPRESSED LONG NON-CODING RNAS (LNCRNAS) FUNCTIONALLY CONNECTED TO MODULATED GENES BOTH DIRECTLY AND VIA MICRORNA TARGETING. ONLY TWO LNCRNAS OF THE 298 FOUND MODULATED IN PATIENTS, WERE ABLE TO TARGET THE MOST HIGHLY CONNECTED GENES IN THE FIBROMYALGIA INTERACTOME, SUGGESTING THEIR INVOLVEMENT IN CRUCIAL GENE REGULATION. OUR GENE EXPRESSION DATA WERE CONFIRMED BY REAL TIME PCR, BY AUTOANTIBODY TESTING, DETECTION OF SOLUBLE MEDIATORS AND TH-17 POLARIZATION IN A VALIDATION COHORT OF 50 PATIENTS. OUR RESULTS INDICATE THAT GENETIC AND EPIGENETIC MECHANISMS AS WELL AS AUTOIMMUNITY PLAY A PIVOTAL ROLE IN THE PATHOGENESIS OF FIBROMYALGIA. 2020 4 4285 33 MICRORNA EPIGENETIC SIGNATURES IN HUMAN DISEASE. MICRORNAS (MIRNAS) ARE SHORT NON-CODING RNAS THAT ACT AS IMPORTANT REGULATORS OF GENE EXPRESSION AS PART OF THE EPIGENETIC MACHINERY. IN ADDITION TO POSTTRANSCRIPTIONAL GENE SILENCING BY MIRNAS, THE EPIGENETIC MECHANISMS ALSO INCLUDE DNA METHYLATION, HISTONE MODIFICATIONS AND THEIR CROSSTALK. EPIGENETIC MODIFICATIONS WERE REPORTED TO PLAY AN IMPORTANT ROLE IN MANY DISEASE ONSETS AND PROGRESSIONS AND CAN BE USED TO EXPLAIN SEVERAL FEATURES OF COMPLEX DISEASES, SUCH AS LATE ONSET AND FLUCTUATION OF SYMPTOMS. HOWEVER, MIRNAS NOT ONLY FUNCTION AS A PART OF EPIGENETIC MACHINERY, BUT ARE ALSO EPIGENETICALLY MODIFIED BY DNA METHYLATION AND HISTONE MODIFICATION LIKE ANY OTHER PROTEIN-CODING GENE. THERE IS A STRONG CONNECTION BETWEEN EPIGENOME AND MIRNOME, AND ANY DYSREGULATION OF THIS COMPLEX SYSTEM CAN RESULT IN VARIOUS PHYSIOLOGICAL AND PATHOLOGICAL CONDITIONS. IN ADDITION, MIRNAS PLAY AN IMPORTANT ROLE IN TOXICOGENOMICS AND MAY EXPLAIN THE RELATIONSHIP BETWEEN TOXICANT EXPOSURE AND TUMORIGENESIS. THE PRESENT REVIEW PROVIDES INFORMATION ON 63 MIRNA GENES SHOWN TO BE EPIGENETICALLY REGULATED IN ASSOCIATION WITH 21 DISEASES, INCLUDING 11 CANCER TYPES: CARDIAC FIBROSIS, CARDIOVASCULAR DISEASE, PREECLAMPSIA, HIRSCHSPRUNG'S DISEASE, RHEUMATOID ARTHRITIS, SYSTEMIC SCLEROSIS, SYSTEMIC LUPUS ERYTHEMATOSUS, TEMPORAL LOBE EPILEPSY, AUTISM, PULMONARY FIBROSIS, MELANOMA, ACUTE MYELOID LEUKEMIA, CHRONIC LYMPHOCYTIC LEUKEMIA, COLORECTAL, GASTRIC, CERVICAL, OVARIAN, PROSTATE, LUNG, BREAST, AND BLADDER CANCER. THE REVIEW REVEALED THAT HSA-MIR-34A, HSA-MIR-34B, AND HSA-MIR-34C ARE THE MOST FREQUENTLY REPORTED EPIGENETICALLY DYSREGULATED MIRNAS. THERE IS A NEED TO FURTHER STUDY MOLECULAR MECHANISMS OF VARIOUS DISEASES TO BETTER UNDERSTAND THE CROSSTALK BETWEEN EPIGENETICS AND GENE EXPRESSION AND TO DEVELOP NEW THERAPEUTIC OPTIONS AND BIOMARKERS. 2016 5 1020 26 CIRCRNAS IN ATHEROSCLEROSIS, WITH SPECIAL EMPHASIS ON THE SPONGY EFFECT OF CIRCRNAS ON MIRNAS. ATHEROSCLEROSIS (AS) IS A CHRONIC INFLAMMATORY DISEASE, WHICH LEADS TO ATHEROSCLEROTIC RUPTURE, LUMEN STENOSIS AND THROMBOSIS, AND OFTEN ENDANGERS LIFE. CIRCULAR RNAS (CIRCRNAS) ARE A SPECIAL CLASS OF NON-CODING RNA MOLECULES, WHOSE ABNORMAL EXPRESSION HAS BEEN PROVED TO BE CLOSELY RELATED TO HUMAN DISEASES, INCLUDING AS. BOTH THE ABNORMAL REGULATION OF CIRCRNAS AND THE SPONGING EFFECT ON MIRNAS WOULD LEAD TO CHANGES IN GENE EXPRESSION IN THE FORM OF EPIGENETIC MODIFICATION, ULTIMATELY LEADING TO THE FORMATION OF AS. CIRCRNAS CAN BE USED AS PERIPHERAL BLOOD MARKERS OF AS, AND PLAY AN IMPORTANT REGULATORY ROLE IN THE PROLIFERATION, MIGRATION, INFLAMMATION AND APOPTOSIS OF VASCULAR SMOOTH MUSCLE CELLS, ENDOTHELIAL CELLS AND MACROPHAGE, WHICH ARE KEY CELLS FOR THE DEVELOPMENT OF AS. THE IN-DEPTH UNDERSTANDING OF CIRCRNAS IN AS NOT ONLY PROVIDES A NEW METHOD FOR THE DIAGNOSIS OF AS, BUT ALSO PROVIDES A NEW IDEA FOR THE TREATMENT OF AS. 2023 6 5120 33 POSSIBLE EPIGENETIC REGULATORY EFFECT OF DYSREGULATED CIRCULAR RNAS IN EPILEPSY. CIRCULAR RNAS (CIRCRNAS) INVOLVE IN THE EPIGENETIC REGULATION AND ITS MAJOR MECHANISM IS THE SEQUESTRATION OF THE TARGET MICRO RNAS (MIRNAS). WE HYPOTHESIZED THAT CIRCRNAS MIGHT BE RELATED WITH THE PATHOPHYSIOLOGY OF CHRONIC EPILEPSY AND EVALUATED THE ALTERED CIRCRNA EXPRESSIONS AND THEIR POSSIBLE REGULATORY EFFECTS ON THEIR TARGET MIRNAS AND MRNAS IN A MOUSE EPILEPSY MODEL. THE CIRCRNA EXPRESSION PROFILE IN THE HIPPOCAMPUS OF THE PILOCARPINE MICE WAS ANALYZED AND COMPARED WITH CONTROL. THE CORRELATION BETWEEN THE EXPRESSION OF MIRNA BINDING SITES (MIRNA RESPONSE ELEMENTS, MRE) IN THE DYSREGULATED CIRCRNAS AND THE EXPRESSION OF THEIR TARGET MIRNAS WAS EVALUATED. AS MIRNAS ALSO INHIBIT THEIR TARGET MRNAS, CIRCRNA-MIRNA-MRNA REGULATORY NETWORK, COMPRISED OF DYSREGULATED RNAS THAT TARGETS ONE ANOTHER WERE SEARCHED. FOR THE IDENTIFIED NETWORKS, BIOINFORMATICS ANALYSES WERE PERFORMED. AS THE RESULT, FORTY-THREE CIRCRNAS WERE DYSREGULATED IN THE HIPPOCAMPUS (UP-REGULATED, 26; DOWN-REGULATED, 17). THE CHANGE IN THE EXPRESSION OF MRE IN THOSE CIRCRNAS NEGATIVELY CORRELATED WITH THE CHANGE IN THE RELEVANT TARGET MIRNA EXPRESSION (R = -0.461, P<0.001), SUPPORTING THAT CIRCRNAS INHIBIT THEIR TARGET MIRNA. 333 DYSREGULATED CIRCRNA-MIRNA-MRNA NETWORKS WERE IDENTIFIED. GENE ONTOLOGY AND PATHWAY ANALYSES DEMONSTRATED THAT THE UP-REGULATED MRNAS IN THOSE NETWORKS WERE CLOSELY RELATED TO THE MAJOR PROCESSES IN EPILEPSY. AMONG THEM, STRING ANALYSIS IDENTIFIED 37 KEY MRNAS WITH ABUNDANT (>/=4) INTERACTIONS WITH OTHER DYSREGULATED TARGET MRNAS. THE DYSREGULATION OF THE CIRCRNAS WHICH HAD MULTIPLE INTERACTIONS WITH KEY MRNAS WERE VALIDATED BY PCR. WE CONCLUDED THAT DYSREGULATED CIRCRNAS MIGHT HAVE A PATHOPHYSIOLOGIC ROLE IN CHRONIC EPILEPSY BY REGULATING MULTIPLE DISEASE RELEVANT MRNAS VIA CIRCRNA-MIRNA-MRNA INTERACTIONS. 2018 7 3772 23 INTERACTION BETWEEN MICRORNA AND DNA METHYLATION IN ATHEROSCLEROSIS. ATHEROSCLEROSIS (AS) IS A CHRONIC INFLAMMATORY DISEASE ACCOMPANIED BY COMPLEX PATHOLOGICAL CHANGES, SUCH AS ENDOTHELIAL DYSFUNCTION, FOAM CELL FORMATION, AND VASCULAR SMOOTH MUSCLE CELL PROLIFERATION. MANY APPROACHES, INCLUDING REGULATING AS-RELATED GENE EXPRESSION IN THE TRANSCRIPTIONAL OR POST-TRANSCRIPTIONAL LEVEL, CONTRIBUTE TO ALLEVIATING AS DEVELOPMENT. THE DNA METHYLATION IS A CRUCIAL EPIGENETIC MODIFICATION IN REGULATING CELL FUNCTION BY SILENCING THE RELATIVE GENE EXPRESSION. THE MICRORNA (MIRNA) IS A TYPE OF NONCODING RNA THAT PLAYS AN IMPORTANT ROLE IN GENE POST-TRANSCRIPTIONAL REGULATION AND DISEASE DEVELOPMENT. THE DNA METHYLATION AND THE MIRNA ARE IMPORTANT EPIGENETIC FACTORS IN AS. HOWEVER, RECENT STUDIES HAVE FOUND A MUTUAL REGULATION BETWEEN THESE TWO FACTORS IN AS DEVELOPMENT. IN THIS STUDY, RECENT INSIGHTS INTO THE ROLES OF MIRNA AND DNA METHYLATION AND THEIR INTERACTION IN THE AS PROGRESSION ARE REVIEWED. 2021 8 3961 34 LONG NON-CODING RNAS: THE NEW FRONTIER INTO UNDERSTANDING THE ETIOLOGY OF ALCOHOL USE DISORDER. ALCOHOL USE DISORDER (AUD) IS A COMPLEX, CHRONIC, DEBILITATING CONDITION IMPACTING MILLIONS WORLDWIDE. GENETIC, ENVIRONMENTAL, AND EPIGENETIC FACTORS ARE KNOWN TO CONTRIBUTE TO THE DEVELOPMENT OF AUD. LONG NON-CODING RNAS (LNCRNAS) ARE A CLASS OF REGULATORY RNAS, COMMONLY REFERRED TO AS THE "DARK MATTER" OF THE GENOME, WITH LITTLE TO NO PROTEIN-CODING POTENTIAL. LNCRNAS HAVE BEEN IMPLICATED IN NUMEROUS PROCESSES CRITICAL FOR CELL SURVIVAL, SUGGESTING THAT THEY PLAY IMPORTANT FUNCTIONAL ROLES IN REGULATING DIFFERENT CELL PROCESSES. LNCRNAS WERE ALSO SHOWN TO DISPLAY HIGHER TISSUE SPECIFICITY THAN PROTEIN-CODING GENES AND HAVE A HIGHER ABUNDANCE IN THE BRAIN AND CENTRAL NERVOUS SYSTEM, DEMONSTRATING A POSSIBLE ROLE IN THE ETIOLOGY OF PSYCHIATRIC DISORDERS. INDEED, GENETIC (E.G., GENOME-WIDE ASSOCIATION STUDIES (GWAS)), MOLECULAR (E.G., EXPRESSION QUANTITATIVE TRAIT LOCI (EQTL)) AND EPIGENETIC STUDIES FROM POSTMORTEM BRAIN TISSUES HAVE IDENTIFIED A GROWING LIST OF LNCRNAS ASSOCIATED WITH NEUROPSYCHIATRIC AND SUBSTANCE USE DISORDERS. GIVEN THAT THE EXPRESSION PATTERNS OF LNCRNAS HAVE BEEN ASSOCIATED WITH WIDESPREAD CHANGES IN THE TRANSCRIPTOME, INCLUDING METHYLATION, CHROMATIN ARCHITECTURE, AND ACTIVATION OR SUPPRESSION OF TRANSLATIONAL ACTIVITY, THE REGULATORY NATURE OF LNCRNAS MAY BE UBIQUITOUS AND AN INNATE COMPONENT OF GENE REGULATION. IN THIS REVIEW, WE PRESENT A SYNOPSIS OF THE FUNCTIONAL IMPACT THAT LNCRNAS MAY PLAY IN THE ETIOLOGY OF AUD. WE ALSO DISCUSS THE CLASSIFICATIONS OF LNCRNAS, THEIR KNOWN FUNCTIONAL ROLES, AND THERAPEUTIC ADVANCEMENTS IN THE FIELD OF LNCRNAS TO FURTHER CLARIFY THE FUNCTIONAL RELATIONSHIP BETWEEN LNCRNAS AND AUD. 2022 9 6907 29 [THE ROLE OF THE CIRCULAR RNAS IN MULTIPLE SCLEROSIS AND OTHER NEUROIMMUNE DISORDERS]. IN RECENT YEARS NON-CODING RNAS HAVE RECEIVED INCREASING ATTENTION AS AN IMPORTANT EPIGENETIC MECHANISM, WITH PARTICULAR ROLE OF MICRO RNAS. AS THE REGULATION OF MIRNA EXPRESSION IS HIGHLY DYNAMIC AND COMPLEX, GROWING EVIDENCE SUGGESTS THE EXISTENCE OF ANOTHER HIGHER LEVEL OF REGULATORY MECHANISM INVOLVED IN MIRNA ACTIVITY - CIRCULAR RNAS (CIRCRNAS). CIRCRNAS REPRESENT NOVEL, UNIQUE CLASS OF ENDOGENOUS NCRNAS CONTROLLING THE EXPRESSION AND FUNCTION OF MIRNA. THEY ARE CALLED NATURAL MIRNA "SPONGES". ACCUMULATING EVIDENCE REVEALS CIRCRNAS ROLE IN PHYSIOLOGICAL AND PATHOLOGICAL PROCESSES INCLUDING CNS AND IMMUNE REGULATION. PREVIOUS STUDIES IMPLICATED MIRNAS IN REGULATION OF AUTOIMMUNE DEMYELINATION IN MS. MULTIPLE SCLEROSIS IS A CHRONIC NEUROLOGICAL INFLAMMATORY DEMYELINATING DISORDER OF THE CENTRAL NERVOUS SYSTEM. WHILE THE ETIOLOGY OF MS IS STILL NOT FULLY UNDERSTOOD, ACCUMULATING EVIDENCE SUGGESTS THAT IT IS A MULTIFACTORIAL ENTITY WITH SIGNIFICANT INVOLVEMENT OF AUTOIMMUNE PROCESSES. 2022 10 4289 25 MICRORNA IN OSTEOARTHRITIS. OSTEOARTHRITIS (OA) IS THE MOST PREVALENT DEGENERATIVE JOINT DISEASE AND IS ACCOMPANIED BY PAIN AND JOINT DYSFUNCTION. ITS CLINICAL TREATMENT TENDS TO BE UNSATISFACTORY. NOVEL TARGETS IN OA INCLUDE GENES THAT ARE INVOLVED IN OA PATHOPHYSIOLOGY AND HAVE BEEN DISCOVERED USING GENE NETWORK, EPIGENETIC AND MICRORNA (MIRNA) APPROACHES. MIRNA HAS BEEN IMPLICATED IN IMPORTANT CELLULAR PROCESSES SUCH AS LIPID METABOLISM, APOPTOSIS, DIFFERENTIATION AND ORGAN DEVELOPMENT. THE IMPORTANCE OF MIRNA REGULATION IN CELLULAR FUNCTION IS BECOMING INCREASINGLY CLEAR AS NEW MIRNA TARGETS ARE REVEALED. THE PRESENT REVIEW SUMMARIZES THE CURRENT EVIDENCE OF THE IMPORTANT ROLE PLAYED BY MIRNA IN DETERMINING THE COMPLEX GENE EXPRESSION PATTERNS OF OA CHONDROCYTES AND THEIR ROLE IN THE REGULATION OF TRANSCRIPTION, AND POSSIBLE DEMETHYLATION MECHANISMS THAT MIGHT BE APPLICABLE IN OA. IN SUMMARY, MIRNA MAY HAVE IMPORTANT DIAGNOSTIC AND THERAPEUTIC POTENTIAL, AND MIGHT PROVIDE A NOVEL MEANS OF TREATING OA. 2011 11 4330 36 MICRORNAS: AN EPIGENETIC TOOL TO STUDY CELIAC DISEASE. THIS ARTICLE SUMMARIZES RECENT FINDINGS ON THE ROLE OF MICRORNAS (MIRNAS) IN BIOLOGICAL PROCESSES ASSOCIATED WITH THE REGULATION OF CHRONIC INFLAMMATION AND AUTOIMMUNITY. MIRNAS ARE SMALL NON-CODING RNA MOLECULES THAT HAVE BEEN RECENTLY EMERGED AS A NEW CLASS OF MODULATORS OF GENE EXPRESSION AT THE POST-TRANSCRIPTIONAL LEVEL. MIRNAS BIND TO COMPLEMENTARY SEQUENCES OF SPECIFIC TARGETS OF MESSENGERS RNA, WHICH CAN INTERFERE WITH PROTEIN SYNTHESIS. WE REVIEWED STUDIES THAT EVALUATED THE EXPRESSION PATTERNS OF MIRNAS IN DIFFERENT AUTOIMMUNE DISEASES, ESPECIALLY IN CELIAC DISEASE (CD). CD IS A CHRONIC ENTEROPATHY TRIGGERED BY GLUTEN PROTEINS, CHARACTERIZED BY ALTERED IMMUNE RESPONSES IN GENETICALLY SUSCEPTIBLE INDIVIDUALS THAT RESULTS IN DAMAGE TO THE BOWEL MUCOSA. CD HAS A HIGH PREVALENCE AND AN EFFECTIVE TREATMENT BY A SPECIFIC DIET ("GLUTEN FREE DIET"). GENETIC FACTORS CONFER SUSCEPTIBILITY BUT DO NOT EXPLAIN THE WHOLE DISEASE, SUGGESTING THAT ENVIRONMENTAL FACTORS DO PLAY A RELEVANT ROLE IN THE DEVELOPMENT OF THE CONDITION.THE EVALUATION OF THE POTENTIAL ROLE OF MIRNA IS OF PARTICULAR INTEREST IN CD GIVEN THAT THESE EPIGENETIC MECHANISMS IN THE PATHOGENESIS OF AUTOIMMUNE AND INFLAMMATORY DISEASES HAVE BEEN RECENTLY DESCRIBED. IMPROVING OUR UNDERSTANDING OF MIRNAS IN CD WILL CONTRIBUTE TO CLARIFY THE ROLE OF ALTERED EPIGENETIC REGULATION IN THE DEVELOPMENT AND COURSE OF THIS DISEASE. 2014 12 4323 28 MICRORNAS IN PSYCHOLOGICAL STRESS REACTIONS AND THEIR USE AS STRESS-ASSOCIATED BIOMARKERS, ESPECIALLY IN HUMAN SALIVA. MICRORNAS (MIRNAS) PLAY A CENTRAL ROLE IN THE REGULATION OF MANY CELLULAR PROCESSES INCLUDING PHYSIOLOGICAL AND PSYCHOLOGICAL STRESS REACTION PATHWAYS. PSYCHOLOGICAL STRESS IS AN IMPORTANT FACTOR FOR THE GENESIS AND MAINTENANCE OF MANY DISEASES. SEVERAL MIRNAS HAVE ALREADY BEEN DESCRIBED TO BE INVOLVED IN ITS REGULATION. THE PRESENCE OF MIRNAS IN ALL BODY FLUIDS IMPLIES A WIDESPREAD ROLE IN COMMUNICATION THROUGHOUT THE WHOLE ORGANISM AND TOGETHER WITH THEIR STABILITY MAKES THEM FORMIDABLE CANDIDATES AS BIOMARKERS. ALTERATIONS OF STRESS-ASSOCIATED MIRNA EXPRESSION LEVELS HAVE BEEN FOUND IN THE BRAIN AND WHOLE BLOOD OF HUMANS AND ANIMALS. IN THIS PAPER, WE REVIEW THE PARTICIPATION OF MIRNAS IN STRESS-REACTIVE PROCESSES AS WELL AS THEIR USABILITY AS SALIVARY BIOMARKERS OF SUCH PROCESSES. IN CONCLUSION, WE SUGGEST THAT SALIVARY MIRNAS MAY BE USEFUL AS NONINVASIVE BIOMARKERS TO ASSESS EPIGENETIC REGULATION PROCESSES OF CHRONIC OR ACUTE PSYCHOLOGICAL STRESS REACTIONS. 2017 13 5495 34 REVIEW ON CIRCULAR RNAS AND NEW INSIGHTS INTO THEIR ROLES IN CANCER. CIRCULAR RNAS (CIRCRNAS) ARE A VERY INTERESTING CLASS OF CONSERVED SINGLE-STRANDED RNA MOLECULES DERIVED FROM EXONIC OR INTRONIC SEQUENCES BY PRECURSOR MRNA BACK-SPLICING. UNLIKE CANONICAL LINEAR RNAS, CIRCRNAS FORM COVALENTLY CLOSED, CONTINUOUS STABLE LOOPS WITHOUT A 5'END CAP AND 3'END POLY(A) TAIL, AND THEREFORE ARE RESISTANT TO EXONUCLEASE DIGESTION. THE MAJORITY OF CIRCRNAS ARE HIGHLY ABUNDANT, AND CONSERVED ACROSS DIFFERENT SPECIES WITH A TISSUE OR DEVELOPMENTAL-STAGE-SPECIFIC EXPRESSION. CIRCRNAS HAVE BEEN SHOWN TO PLAY IMPORTANT ROLES AS MICRORNA SPONGES, REGULATORS OF GENE SPLICING AND TRANSCRIPTION, RNA-BINDING PROTEIN SPONGES AND PROTEIN/PEPTIDE TRANSLATORS. EMERGING EVIDENCE REVEALS THAT CIRCRNAS FUNCTION IN VARIOUS HUMAN DISEASES, PARTICULARLY CANCERS, AND MAY FUNCTION AS BETTER PREDICTIVE BIOMARKERS AND THERAPEUTIC TARGETS FOR CANCER TREATMENT. IN CONSIDERATION OF THEIR POTENTIAL CLINICAL RELEVANCE, CIRCRNAS HAVE BECOME A NEW RESEARCH HOTSPOT IN THE FIELD OF TUMOR PATHOLOGY. IN THE PRESENT STUDY, THE CURRENT UNDERSTANDING OF THE BIOGENESIS, CHARACTERISTICS, DATABASES, RESEARCH METHODS, BIOLOGICAL FUNCTIONS SUBCELLULAR DISTRIBUTION, EPIGENETIC REGULATION, EXTRACELLULAR TRANSPORT AND DEGRADATION OF CIRCRNAS WAS DISCUSSED. IN PARTICULAR, THE MULTIPLE DATABASES AND METHODS INVOLVED IN CIRCRNA RESEARCH WERE FIRST SUMMARIZED, AND THE RECENT ADVANCES IN DETERMINING THE POTENTIAL ROLES OF CIRCRNAS IN TUMOR GROWTH, MIGRATION AND INVASION, WHICH RENDER CIRCRNAS BETTER PREDICTIVE BIOMARKERS, WERE DESCRIBED. FURTHERMORE, FUTURE PERSPECTIVES FOR THE CLINICAL APPLICATION OF CIRCRNAS IN THE MANAGEMENT OF PATIENTS WITH CANCER WERE PROPOSED, WHICH COULD PROVIDE NEW INSIGHTS INTO CIRCRNAS IN THE FUTURE. 2021 14 5256 34 PROGRESSES IN EPIGENETIC STUDIES OF ASTHMA FROM THE PERSPECTIVE OF HIGH-THROUGHPUT ANALYSIS TECHNOLOGIES: A NARRATIVE REVIEW. BACKGROUND AND OBJECTIVE: ASTHMA IS THE MOST COMMON CHRONIC RESPIRATORY DISEASE IN THE WORLD WITH AN ESTIMATED HERITABILITY BETWEEN 50% AND 60%, AND RECENT STUDIES HAVE SHOWN THAT EPIGENETIC MECHANISMS PLAY AN IMPORTANT ROLE IN ITS DEVELOPMENT. MANY CUTTING-EDGE EPIGENETIC RESEARCH TECHNIQUES HAVE BEEN APPLIED TO THE STUDY OF THE PATHOGENESIS OF ASTHMA, WHICH HAS PROMOTED THE DEVELOPMENT OF ASTHMA ETIOLOGY AND BROUGHT NEW POSSIBILITIES FOR TREATMENT. WE SUMMARIZED RECENT ADVANCES IN EPIGENETIC RESEARCH OF THE PATHOGENESIS OF ASTHMA, ESPECIALLY FROM THE PERSPECTIVE OF HIGH-THROUGHPUT ANALYSIS TECHNIQUES, TO FIND POTENTIAL EPIGENETIC BIOMARKERS AND POSSIBLE MOLECULAR TARGETS FOR THE FUTURE INTERVENTION AND TREATMENT OF THE DISEASE. METHODS: WE REVIEWED AND SUMMARIZED RECENT PROGRESS IN EPIGENOMIC STUDIES OF ASTHMA ON A "PRE-TRANSCRIPTIONAL LEVEL", INCLUDING DNA METHYLATION, HISTONE MODIFICATION, AND CHROMATIN REMODELING, AND ON A "POST-TRANSCRIPTIONAL LEVEL" WITH A FOCUS ON NON-CODING RNA, FROM THE PERSPECTIVE OF HIGH-THROUGHPUT ANALYSIS TECHNOLOGIES. KEY CONTENT AND FINDINGS: WE HAVE SUMMARIZED THE PROGRESS OF DIFFERENT KINDS OF RECENT EPIGENETIC STUDIES IN ASTHMA, INCLUDING DNA METHYLATION STUDIES [CANDIDATE GENES METHYLATION STUDIES AND EPIGENOME-WIDE ASSOCIATION STUDY (EWAS)], HISTONE MODIFICATION STUDIES (HISTONE ACETYLATION/DEACETYLATION STUDIES AND HISTONE METHYLATION STUDIES), NON-CODING RNA STUDIES [MICRORNAS (MIRNAS), LONG NON-CODING RNAS (LNCRNAS) AND CIRCULAR RNAS (CIRCRNAS)], TO HELP THE READERS TO GAIN A COMPREHENSIVE INSIGHT INTO THE EPIGENETIC RESEARCH FIELDS FOR ASTHMA. THE APPLICATION OF HIGH-THROUGHPUT ANALYSIS TECHNIQUES IN ASTHMA RESEARCH, INCLUDING EWAS (DNA METHYLATION CHIPS), CHROMATIN IMMUNOPRECIPITATION SEQUENCING (CHIP-SEQ), MICRORNA SEQUENCING, WHOLE TRANSCRIPTOME SEQUENCING, CO-EXPRESSION NETWORK AND COMPETING ENDOGENOUS RNA (CERNA) ANALYSES, WERE INTRODUCED ACCOMPANY WITH THE MAIN FINDINGS. AND THE POTENTIAL EPIGENETIC BIOMARKERS AND POSSIBLE MOLECULAR TARGETS IDENTIFIED VIA HIGH-THROUGHPUT ANALYSES WERE ALSO DISCUSSED. CONCLUSIONS: EPIGENETIC RESEARCH HAS BECOME A HOTSPOT IN RESEARCH ON THE PATHOGENESIS OF ASTHMA. THE COMBINATION OF HIGH-THROUGHPUT EPIGENETIC ANALYSIS TECHNOLOGIES AND TRADITIONAL BIOLOGICAL FUNCTION AND CLINICAL STUDIES WILL BRING NEW BREAKTHROUGH IN THE PATHOGENESIS STUDY OF ASTHMA, WHICH WILL IMPROVE THE GENETIC INTERPRETATION OF THE DISEASE AND BRING MORE POSSIBILITIES FOR THE DEVELOPMENT OF PRECISION MEDICINE TO TREAT IT. 2022 15 4228 21 METHYLATION OF INFLAMMATORY CELLS IN LUNG DISEASES. THIS CHAPTER OVERVIEWS ROLES OF DNA METHYLATION IN INFLAMMATORY CELL BIOLOGY WITH THE FOCUSES ON LYMPHOCYTES AND MACROPHAGES/MONOCYTES IN LUNG DISEASES, ALTHOUGH THE MOLECULAR MECHANISMS BY WHICH TARGET GENES ARE METHYLATED AND REGULATED IN LUNG DISEASES REMAIN UNCLEAR. MOST OF EPIGENETIC STUDIES ON DNA METHYLATION OF TARGET GENES IN LUNG DISEASES MAINLY DEMONSTRATED THE CORRELATION OF DNA METHYLATION OF TARGET GENES WITH THE LEVELS OF OTHER CORRESPONDING FACTORS, WITH THE SPECIFICITY OF CLINICAL PHENOMES, AND WITH THE SEVERITY OF LUNG DISEASES. THERE IS AN URGENT NEED TO IDENTIFY AND VALIDATE THE SPECIFICITY AND REGULATORY MECHANISMS OF INFLAMMATORY CELL EPIGENETICS IN DEPTH. THE EPIGENETIC HETEROGENEITY AMONG DIFFERENT SUBSETS OF T CELLS AND AMONG PROMOTERS OR NON-PROMOTERS OF TARGET GENES SHOULD BE FURTHERMORE CLARIFIED IN ACUTE OR CHRONIC LUNG DISEASES AND CANCERS. THE HYPER/HYPO-METHYLATION AND MODIFICATIONS OF CHROMOSOL AND EXTRACHROMOSOMAL DNA MAY RESULT IN ALTERNATIONS IN PROTEINS WITHIN INFLAMMATORY CELLS, WHICH CAN BE IDENTIFIED AS DISEASE-SPECIFIC BIOMARKERS AND THERAPEUTIC TARGETS. 2020 16 3350 28 HISTONE DEACETYLATION MEETS MIRNA: EPIGENETICS AND POST-TRANSCRIPTIONAL REGULATION IN CANCER AND CHRONIC DISEASES. INTRODUCTION: EPIGENETIC REGULATION VIA DNA METHYLATION, HISTONE ACETYLATION, AS WELL AS BY MICRORNAS (MIRNAS) IS CURRENTLY IN THE SCIENTIFIC FOCUS DUE TO ITS ROLE IN CARCINOGENESIS AND ITS INVOLVEMENT IN INITIATION, PROGRESSION AND METASTASIS. WHILE MANY TARGET GENES OF DNA METHYLATION, HISTONE ACETYLATION AND MIRNAS ARE KNOWN, EVEN LESS INFORMATION EXISTS AS TO HOW THESE MECHANISMS COOPERATE AND HOW THEY MAY REGULATE EACH OTHER IN A SPECIFIC PATHOLOGICAL CONTEXT. FOR FURTHER DEVELOPMENT OF THERAPEUTIC APPROACHES, THIS REVIEW PRESENTS THE CURRENT STATUS OF THE CROSSTALK OF HISTONE ACETYLATION AND MIRNAS IN HUMAN CARCINOGENESIS AND CHRONIC DISEASES. AREAS COVERED: THIS ARTICLE REVIEWS INFORMATION FROM COMPREHENSIVE PUBMED SEARCHES TO EVALUATE RELEVANT LITERATURE WITH A FOCUS ON POSSIBLE ASSOCIATION BETWEEN HISTONE ACETYLATION, MIRNAS AND THEIR TARGETS. OUR ANALYSIS IDENTIFIED SPECIFIC MIRNAS WHICH COLLABORATE WITH HISTONE DEACETYLASES (HDACS) AND COOPERATIVELY REGULATE SEVERAL RELEVANT TARGET GENES. EXPERT OPINION: FOURTEEN MIRNAS COULD BE LINKED TO THE EXPRESSION OF EIGHT HDACS INFLUENCING THE ALPHA-(1,6)-FUCOSYLTRANSFERASE, POLYCYSTIN-2 AND THE FIBROBLAST-GROWTH-FACTOR 2 PATHWAYS. FOCUSING ON THE COMPLEX LINKAGE OF MIRNA AND HDAC EXPRESSION COULD GIVE DEEPER INSIGHTS IN NEW 'DRUGGABLE' TARGETS AND MIGHT PROVIDE POSSIBLE NOVEL THERAPEUTIC APPROACHES IN FUTURE. 2015 17 1518 28 DNA METHYLATION AS AN EPIGENETIC MECHANISM IN THE DEVELOPMENT OF MULTIPLE SCLEROSIS. THE EPIGENETIC MECHANISMS OF GENE EXPRESSION REGULATION ARE A GROUP OF THE KEY CELLULAR AND MOLECULAR PATHWAYS THAT LEAD TO INHERITED ALTERATIONS IN GENES' ACTIVITY WITHOUT CHANGING THEIR CODING SEQUENCE. DNA METHYLATION AT THE C5 POSITION OF CYTOSINE IN CPG DINUCLEOTIDES IS AMONGST THE CENTRAL EPIGENETIC MECHANISMS. CURRENTLY, THE NUMBER OF STUDIES THAT ARE DEVOTED TO THE IDENTIFICATION OF METHYLATION PATTERNS SPECIFIC TO MULTIPLE SCLEROSIS (MS), A SEVERE CHRONIC AUTOIMMUNE DISEASE OF THE CENTRAL NERVOUS SYSTEM, IS ON A RAPID RISE. HOWEVER, THE ISSUE OF THE CONTRIBUTION OF DNA METHYLATION TO THE DEVELOPMENT OF THE DIFFERENT CLINICAL PHENOTYPES OF THIS HIGHLY HETEROGENEOUS DISEASE HAS ONLY BEGUN TO ATTRACT THE ATTENTION OF RESEARCHERS. THIS REVIEW SUMMARIZES THE DATA ON THE MOLECULAR MECHANISMS UNDERLYING DNA METHYLATION AND THE MS RISK FACTORS THAT CAN AFFECT THE DNA METHYLATION PROFILE AND, THEREBY, MODULATE THE EXPRESSION OF THE GENES INVOLVED IN THE DISEASE'S PATHOGENESIS. THE FOCUS OF OUR ATTENTION IS CENTERED ON THE ANALYSIS OF THE PUBLISHED DATA ON THE DIFFERENTIAL METHYLATION OF DNA FROM VARIOUS BIOLOGICAL SAMPLES OF MS PATIENTS OBTAINED USING BOTH THE CANDIDATE GENE APPROACH AND HIGH-THROUGHPUT METHODS. 2021 18 1269 32 CYTOSINE METHYLATION CHANGES IN ENHANCER REGIONS OF CORE PRO-FIBROTIC GENES CHARACTERIZE KIDNEY FIBROSIS DEVELOPMENT. BACKGROUND: ONE IN ELEVEN PEOPLE IS AFFECTED BY CHRONIC KIDNEY DISEASE, A CONDITION CHARACTERIZED BY KIDNEY FIBROSIS AND PROGRESSIVE LOSS OF KIDNEY FUNCTION. EPIDEMIOLOGICAL STUDIES INDICATE THAT ADVERSE INTRAUTERINE AND POSTNATAL ENVIRONMENTS HAVE A LONG-LASTING ROLE IN CHRONIC KIDNEY DISEASE DEVELOPMENT. EPIGENETIC INFORMATION REPRESENTS A PLAUSIBLE CARRIER FOR MEDIATING THIS PROGRAMMING EFFECT. HERE WE DEMONSTRATE THAT GENOME-WIDE CYTOSINE METHYLATION PATTERNS OF HEALTHY AND CHRONIC KIDNEY DISEASE TUBULE SAMPLES OBTAINED FROM PATIENTS SHOW SIGNIFICANT DIFFERENCES. RESULTS: WE IDENTIFY DIFFERENTIALLY METHYLATED REGIONS AND VALIDATE THESE IN A LARGE REPLICATION DATASET. THE DIFFERENTIALLY METHYLATED REGIONS ARE RARELY OBSERVED ON PROMOTERS, BUT MOSTLY OVERLAP WITH PUTATIVE ENHANCER REGIONS, AND THEY ARE ENRICHED IN CONSENSUS BINDING SEQUENCES FOR IMPORTANT RENAL TRANSCRIPTION FACTORS. THIS INDICATES THEIR IMPORTANCE IN GENE EXPRESSION REGULATION. A CORE SET OF GENES THAT ARE KNOWN TO BE RELATED TO KIDNEY FIBROSIS, INCLUDING GENES ENCODING COLLAGENS, SHOW CYTOSINE METHYLATION CHANGES CORRELATING WITH DOWNSTREAM TRANSCRIPT LEVELS. CONCLUSIONS: OUR REPORT RAISES THE POSSIBILITY THAT EPIGENETIC DYSREGULATION PLAYS A ROLE IN CHRONIC KIDNEY DISEASE DEVELOPMENT VIA INFLUENCING CORE PRO-FIBROTIC PATHWAYS AND CAN AID THE DEVELOPMENT OF NOVEL BIOMARKERS AND FUTURE THERAPEUTICS. 2013 19 2523 35 EPIGENETICS AND THE TRANSITION FROM ACUTE TO CHRONIC PAIN. OBJECTIVE: THE OBJECTIVE OF THIS STUDY WAS TO REVIEW THE EPIGENETIC MODIFICATIONS INVOLVED IN THE TRANSITION FROM ACUTE TO CHRONIC PAIN AND TO IDENTIFY POTENTIAL TARGETS FOR THE DEVELOPMENT OF NOVEL, INDIVIDUALIZED PAIN THERAPEUTICS. BACKGROUND: EPIGENETICS IS THE STUDY OF HERITABLE MODIFICATIONS IN GENE EXPRESSION AND PHENOTYPE THAT DO NOT REQUIRE A CHANGE IN GENETIC SEQUENCE TO MANIFEST THEIR EFFECTS. ENVIRONMENTAL TOXINS, MEDICATIONS, DIET, AND PSYCHOLOGICAL STRESSES CAN ALTER EPIGENETIC PROCESSES SUCH AS DNA METHYLATION, HISTONE ACETYLATION, AND RNA INTERFERENCE. AS EPIGENETIC MODIFICATIONS POTENTIALLY PLAY AN IMPORTANT ROLE IN INFLAMMATORY CYTOKINE METABOLISM, STEROID RESPONSIVENESS, AND OPIOID SENSITIVITY, THEY ARE LIKELY KEY FACTORS IN THE DEVELOPMENT OF CHRONIC PAIN. ALTHOUGH OUR KNOWLEDGE OF THE HUMAN GENETIC CODE AND DISEASE-ASSOCIATED POLYMORPHISMS HAS GROWN SIGNIFICANTLY IN THE PAST DECADE, WE HAVE NOT YET BEEN ABLE TO ELUCIDATE THE MECHANISMS THAT LEAD TO THE DEVELOPMENT OF PERSISTENT PAIN AFTER NERVE INJURY OR SURGERY. DESIGN: THIS IS A FOCUSED LITERATURE REVIEW OF EPIGENETIC SCIENCE AND ITS RELATIONSHIP TO CHRONIC PAIN. RESULTS: SIGNIFICANT LABORATORY AND CLINICAL DATA SUPPORT THE NOTION THAT EPIGENETIC MODIFICATIONS ARE AFFECTED BY THE ENVIRONMENT AND LEAD TO DIFFERENTIAL GENE EXPRESSION. SIMILAR TO MECHANISMS INVOLVED IN THE DEVELOPMENT OF CANCER, NEURODEGENERATIVE DISEASE, AND INFLAMMATORY DISORDERS, THE LITERATURE ENDORSES AN IMPORTANT POTENTIAL ROLE FOR EPIGENETICS IN CHRONIC PAIN. CONCLUSIONS: EPIGENETIC ANALYSIS MAY IDENTIFY MECHANISMS CRITICAL TO THE DEVELOPMENT OF CHRONIC PAIN AFTER INJURY, AND MAY PROVIDE NEW PATHWAYS AND TARGET MECHANISMS FOR FUTURE DRUG DEVELOPMENT AND INDIVIDUALIZED MEDICINE. 2012 20 5264 24 PROMISING DIRECTIONS IN ATHEROSCLEROSIS TREATMENT BASED ON EPIGENETIC REGULATION USING MICRORNAS AND LONG NONCODING RNAS. ATHEROSCLEROSIS IS ONE OF THE LEADING CAUSES OF MORTALITY FROM CARDIOVASCULAR DISEASE (CVD) AND IS A CHRONIC INFLAMMATORY DISEASE OF THE MIDDLE AND LARGE ARTERIES CAUSED BY A DISRUPTION OF LIPID METABOLISM. NONCODING RNA (NCRNA), INCLUDING MICRORNA (MIRNA), SMALL INTERFERING RNA (SIRNA) AND LONG NONCODING RNA (LNCRNA), WAS INVESTIGATED FOR THE TREATMENT OF ATHEROSCLEROSIS. REGULATION OF THE EXPRESSION OF NONCODING RNA TARGETS THE CONSTITUENT ELEMENT OF THE PATHOGENESIS OF ATHEROSCLEROSIS. CURRENTLY, MIRNA THERAPY COMMONLY EMPLOYS MIRNA ANTAGONISTS AND MIMIC COMPOUNDS. IN THIS REVIEW, ATTENTION IS FOCUSED ON APPROACHES TO CORRECTING MOLECULAR DISORDERS BASED ON THE GENETIC REGULATION OF THE TRANSCRIPTION OF KEY GENES RESPONSIBLE FOR THE DEVELOPMENT OF ATHEROSCLEROSIS. PROMISING TECHNOLOGIES WERE CONSIDERED FOR THE TREATMENT OF ATHEROSCLEROSIS, AND EXAMPLES ARE GIVEN FOR TECHNOLOGIES THAT HAVE BEEN SHOWN TO BE EFFECTIVE IN CLINICAL TRIALS. 2019