1 4583 68 N6-METHYLADENINE RNA METHYLATION EPIGENETIC MODIFICATION AND KIDNEY DISEASES. RNA METHYLATION MODIFICATION IS A RAPIDLY DEVELOPING FIELD IN EPIGENETICS. N6-METHYLADENSINE (M(6)A) IS THE MOST COMMON INTERNAL MODIFICATION IN EUKARYOTIC MRNA. M(6)A GROUP REGULATES RNA SPLICING, STABILITY, TRANSLOCATION, AND TRANSLATION. ENZYMES CATALYZING THIS PROCESS WERE TERMED AS WRITERS, ERASERS, AND READERS. RECENT STUDIES HAVE FOCUSED ON EXPLORING THE ROLE OF RNA METHYLATION IN HUMAN DISEASES. RNA METHYLATION MODIFICATIONS, PARTICULARLY M(6)A, PLAY IMPORTANT ROLES IN THE PATHOGENESIS OF KIDNEY DISEASES. IN THIS REVIEW, WE PROVIDE A BRIEF DESCRIPTION OF M(6)A AND SUMMARIZE THE IMPACT OF M(6)A ON ACUTE AND CHRONIC KIDNEY DISEASE (CKD) AND POSSIBLE FUTURE STUDY DIRECTIONS FOR THIS RESEARCH. 2023 2 1720 37 DYSREGULATED N6-METHYLADENOSINE (M(6)A) PROCESSING IN HEPATOCELLULAR CARCINOMA. N6-METHYLADENOSINE (M(6)A) IS THE MOST THOROUGHLY STUDIED TYPE OF INTERNAL RNA MODIFICATION, AS THIS EPIGENETIC MODIFICATION IS THE MOST ABUNDANT IN EUKARYOTIC RNAS TO DATE. THIS MODIFICATION OCCURS IN VARIOUS TYPES OF RNAS AND PLAYS SIGNIFICANT ROLES IN DOMINANT RNA-RELATED PROCESSES, SUCH AS TRANSLATION, SPLICING, EXPORT AND DEGRADATION. THESE PROCESSES ARE CATALYZED BY THREE TYPES OF PROMINENT ENZYMES: WRITERS, ERASERS AND READERS. INCREASING EVIDENCE HAS SHOWN THAT M(6)A MODIFICATION IS VITAL FOR THE REGULATION OF GENE EXPRESSION, CARCINOGENESIS, TUMOR PROGRESSION AND OTHER ABNORMAL CHANGES, AND RECENT STUDIES HAVE SHOWN THAT M(6)A IS IMPORTANT IN THE DEVELOPMENT OF HEPATOCELLULAR CARCINOMA (HCC). HEREIN, WE SUMMARIZE THE NATURE AND REGULATORY MECHANISMS OF M(6)A MODIFICATION, INCLUDING ITS ROLE IN THE PATHOGENESIS OF HCC AND RELATED CHRONIC LIVER DISEASES. WE ALSO HIGHLIGHT THE CLINICAL SIGNIFICANCE AND FUTURE STRATEGIES INVOLVING RNA M(6)A MODIFICATIONS IN HCC. 2021 3 6144 27 THE EVOLVING LANDSCAPE OF N(6)-METHYLADENOSINE MODIFICATION IN THE TUMOR MICROENVIRONMENT. THE TUMOR MICROENVIRONMENT (TME), CONTROLLED BY INTRINSIC MECHANISMS OF CARCINOGENESIS AND EPIGENETIC MODIFICATIONS, HAS, IN RECENT YEARS, BECOME A HEAVILY RESEARCHED TOPIC. THE TME CAN BE DESCRIBED IN TERMS OF HYPOXIA, METABOLIC DYSREGULATION, IMMUNE ESCAPE, AND CHRONIC INFLAMMATION. RNA METHYLATION, AN EPIGENETIC MODIFICATION, HAS RECENTLY BEEN FOUND TO HAVE A PIVOTAL ROLE IN SHAPING THE TME. THE N(6)-METHYLATION OF ADENOSINE (M(6)A) MODIFICATION IS THE MOST COMMON TYPE OF RNA METHYLATION THAT OCCURS IN THE N(6)-POSITION OF ADENOSINE, WHICH IS THE PRIMARY INTERNAL MODIFICATION OF EUKARYOTIC MRNA. COMPELLING EVIDENCE HAS DEMONSTRATED THAT M(6)A REGULATES TRANSCRIPTIONAL AND PROTEIN EXPRESSION THROUGH SPLICING, TRANSLATION, DEGRADATION, AND EXPORT, THEREBY MEDIATING THE BIOLOGICAL PROCESSES OF CANCER CELLS AND/OR STROMAL CELLS AND CHARACTERIZING THE TME. THE TME ALSO HAS A CRUCIAL ROLE IN THE COMPLICATED REGULATORY NETWORK OF M(6)A MODIFICATIONS AND, SUBSEQUENTLY, INFLUENCES TUMOR INITIATION, PROGRESSION, AND THERAPY RESPONSES. IN THIS REVIEW, WE DESCRIBE THE FEATURES OF THE TME AND HOW THE M(6)A MODIFICATION MODULATES AND INTERACTS WITH IT. WE ALSO FOCUS ON VARIOUS FACTORS AND PATHWAYS INVOLVED IN M(6)A METHYLATION. FINALLY, WE DISCUSS POTENTIAL THERAPEUTIC STRATEGIES AND PROGNOSTIC BIOMARKERS WITH RESPECT TO THE TME AND M(6)A MODIFICATION. 2021 4 3826 28 INVESTIGATION OF EPIGENETICS IN KIDNEY CELL BIOLOGY. EPIGENETICS IS THE STUDY OF HERITABLE CHANGES IN DNA OR ITS ASSOCIATED PROTEINS EXCEPT MUTATIONS IN GENE SEQUENCE. EPIGENETIC REGULATION PLAYS FUNDAMENTAL ROLES IN THE PROCESSES OF KIDNEY CELL BIOLOGY THROUGH THE ACTION OF DNA METHYLATION, CHROMATIN MODIFICATIONS VIA EPIGENETIC REGULATORS AND INTERACTION VIA TRANSCRIPTION FACTORS, AND NONCODING RNA SPECIES. KIDNEY DISEASES, INCLUDING ACUTE KIDNEY INJURY, CHRONIC KIDNEY DISEASE, NEPHRITIC AND NEPHROTIC SYNDROMES, PYELONEPHRITIS AND POLYCYSTIC KIDNEY DISEASES ARE DRIVEN BY ABERRANT ACTIVITY IN NUMEROUS SIGNALING PATHWAYS IN EVEN INDIVIDUAL KIDNEY CELL. EPIGENETIC ALTERATIONS, INCLUDING DNA METHYLATION, HISTONE ACETYLATION AND METHYLATION, NONCODING RNAS, AND PROTEIN POSTTRANSLATIONAL MODIFICATIONS, COULD DISRUPT ESSENTIAL PATHWAYS THAT PROTECT THE RENAL CELLS FROM UNCONTROLLED GROWTH, APOPTOSIS AND ESTABLISHMENT OF OTHER RENAL ASSOCIATED SYNDROMES, WHICH HAVE BEEN RECOGNIZED AS ONE OF THE CRITICAL MECHANISMS FOR REGULATING FUNCTIONAL CHANGES THAT DRIVE AND MAINTAIN THE KIDNEY DISEASE PHENOTYPE. IN THIS CHAPTER, WE BRIEFLY SUMMARIZE THE EPIGENETIC MECHANISMS IN KIDNEY CELL BIOLOGY AND EPIGENETIC BASIS OF KIDNEY DEVELOPMENT, AND INTRODUCE EPIGENETIC TECHNIQUES THAT CAN BE USED IN INVESTIGATING THE MOLECULAR MECHANISM OF KIDNEY CELL BIOLOGY AND KIDNEYS DISEASES, PRIMARILY FOCUSING ON THE INTEGRATION OF DNA METHYLATION AND CHROMATIN IMMUNOPRECIPITATION TECHNOLOGIES INTO KIDNEY DISEASE ASSOCIATED STUDIES. FUTURE STUDIES USING THESE EMERGING TECHNOLOGIES WILL ELUCIDATE HOW ALTERATIONS IN THE RENAL CELL EPIGENOME COOPERATE WITH GENETIC ABERRATIONS FOR KIDNEY DISEASE INITIATION AND PROGRESSION. INCORPORATING EPIGENOMIC TESTING INTO THE CLINICAL RESEARCH IS ESSENTIAL TO FUTURE STUDIES WITH EPIGENETICS BIOMARKERS AND PRECISION MEDICINE USING EMERGING EPIGENETIC THERAPIES. 2019 5 5529 28 RNA N(6) -METHYLADENOSINE MODIFICATIONS AND POTENTIAL TARGETED THERAPEUTIC STRATEGIES IN KIDNEY DISEASE. EPIGENETIC MODIFICATIONS HAVE RECEIVED INCREASING ATTENTION AND HAVE BEEN SHOWN TO BE EXTENSIVELY INVOLVED IN KIDNEY DEVELOPMENT AND DISEASE PROGRESSION. AMONG THEM, THE MOST COMMON RNA MODIFICATION, N(6) -METHYLADENOSINE (M(6) A), HAS BEEN SHOWN TO DYNAMICALLY AND REVERSIBLY EXERT ITS FUNCTIONS IN MULTIPLE WAYS, INCLUDING SPLICING, EXPORT, DECAY AND TRANSLATION INITIATION EFFICIENCY TO REGULATE MRNA FATE. MOREOVER, M(6) A HAS ALSO BEEN REPORTED TO EXERT BIOLOGICAL EFFECTS BY DESTABILIZING BASE PAIRING TO MODULATE VARIOUS FUNCTIONS OF RNAS. MOST IMPORTANTLY, AN INCREASING NUMBER OF KIDNEY DISEASES, SUCH AS RENAL CELL CARCINOMA, ACUTE KIDNEY INJURY AND CHRONIC KIDNEY DISEASE, HAVE BEEN FOUND TO BE ASSOCIATED WITH ABERRANT M(6) A PATTERNS. IN THIS REVIEW, WE COMPREHENSIVELY REVIEW THE CRITICAL ROLES OF M(6) A IN KIDNEY DISEASES AND DISCUSS THE POSSIBILITIES AND RELEVANCE OF M(6) A-TARGETED EPIGENETIC THERAPY, WITH AN INTEGRATED COMPREHENSIVE DESCRIPTION OF THE DETAILED ALTERATIONS IN SPECIFIC LOCI THAT CONTRIBUTE TO CELLULAR PROCESSES THAT ARE ASSOCIATED WITH KIDNEY DISEASES. 2023 6 2341 25 EPIGENETIC REGULATION OF LIVER FIBROSIS. FIBROSIS IS A COMMON AND IMPORTANT PATHOLOGY ASSOCIATED WITH PROGRESSIVE CHRONIC LIVER DISEASES AND UNDERLIES THE DEVELOPMENT OF CIRRHOSIS AND HEPATOCELLULAR CARCINOMA. RESEARCH INTO THE MOLECULAR REGULATION OF FIBROSIS HAS DISCOVERED THAT IT IS UNDER THE CONTROL OF A NUMBER OF EPIGENETIC MECHANISMS INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS AND THE ACTIVITIES OF NON-CODING RNAS. A DEEPER UNDERSTANDING OF HOW EPIGENETIC REGULATORS SUCH AS DNA METHYLTRANSERASES, METHYL-DNA BINDING PROTEINS, HISTONE MODIFYING ENZYMES AND REGULATORY RNA MOLECULES IMPACT ON THE FIBROGENIC PROCESS IS EXPECTED TO RESULT IN NEW BIOMARKERS FOR DISEASE PROGRESSION AS WELL AS NOVEL THERAPEUTIC TARGETS. THE AIM OF THIS MINI-REVIEW IS TO BRIEFLY INTRODUCE THE READER TO THE MAJOR EPIGENETIC REGULATORS SO FAR IDENTIFIED AS BEING IMPLICATED IN FIBROSIS. 2015 7 2283 25 EPIGENETIC REGULATION IN FIBROSIS PROGRESS. FIBROSIS, A COMMON PROCESS OF CHRONIC INFLAMMATORY DISEASES, IS DEFINED AS A REPAIR RESPONSE DISORDER WHEN ORGANS UNDERGO CONTINUOUS DAMAGE, ULTIMATELY LEADING TO SCAR FORMATION AND FUNCTIONAL FAILURE. AROUND THE WORLD, FIBROTIC DISEASES CAUSE HIGH MORTALITY, UNFORTUNATELY, WITH LIMITED TREATMENT MEANS IN CLINICAL PRACTICE. WITH THE DEVELOPMENT AND APPLICATION OF DEEP SEQUENCING TECHNOLOGY, COMPREHENSIVELY EXPLORING THE EPIGENETIC MECHANISM IN FIBROSIS HAS BEEN ALLOWED. EXTENSIVE REMODELING OF EPIGENETICS CONTROLLING VARIOUS CELLS PHENOTYPE AND MOLECULAR MECHANISMS INVOLVED IN FIBROGENESIS WAS SUBSEQUENTLY VERIFIED. IN THIS REVIEW, WE SUMMARIZE THE REGULATORY MECHANISMS OF DNA METHYLATION, HISTONE MODIFICATION, NONCODING RNAS (NCRNAS) AND N6-METHYLADENOSINE (M6A) MODIFICATION IN ORGAN FIBROSIS, FOCUSING ON HEART, LIVER, LUNG AND KIDNEY. ADDITIONALLY, WE EMPHASIZE THE DIVERSITY OF EPIGENETICS IN THE CELLULAR AND MOLECULAR MECHANISMS RELATED TO FIBROSIS. FINALLY, THE POTENTIAL AND PROSPECT OF TARGETED THERAPY FOR FIBROSIS BASED ON EPIGENETIC IS DISCUSSED. 2021 8 2589 22 EPIGENETICS OF PROGRESSION OF CHRONIC KIDNEY DISEASE: FACT OR FANTASY? EPIGENETIC MODIFICATIONS ARE IMPORTANT IN THE NORMAL FUNCTIONING OF THE CELL, FROM REGULATING DYNAMIC EXPRESSION OF ESSENTIAL GENES AND ASSOCIATED PROTEINS TO REPRESSING THOSE THAT ARE UNNEEDED. EPIGENETIC CHANGES ARE ESSENTIAL FOR DEVELOPMENT AND FUNCTIONING OF THE KIDNEY, AND ABERRANT METHYLATION, HISTONE MODIFICATIONS, AND EXPRESSION OF MICRORNA COULD LEAD TO CHRONIC KIDNEY DISEASE (CKD). HERE, EPIGENETIC MODIFICATIONS MODULATE TRANSFORMING GROWTH FACTOR BETA SIGNALING, INFLAMMATION, PROFIBROTIC GENES, AND THE EPITHELIAL-TO-MESENCHYMAL TRANSITION, PROMOTING RENAL FIBROSIS AND PROGRESSION OF CKD. IDENTIFICATION OF THESE EPIGENETIC CHANGES IS IMPORTANT BECAUSE THEY ARE POTENTIALLY REVERSIBLE AND MAY SERVE AS THERAPEUTIC TARGETS IN THE FUTURE TO PREVENT SUBSEQUENT RENAL FIBROSIS AND CKD. IN THIS REVIEW WE DISCUSS THE DIFFERENT TYPES OF EPIGENETIC CONTROL, METHODS TO STUDY EPIGENETIC MODIFICATIONS, AND HOW EPIGENETICS PROMOTES PROGRESSION OF CKD. 2013 9 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 10 2542 26 EPIGENETICS IN KIDNEY DISEASES. EPIGENETICS EXAMINES HERITABLE CHANGES IN DNA AND ITS ASSOCIATED PROTEINS EXCEPT MUTATIONS IN GENE SEQUENCE. EPIGENETIC REGULATION PLAYS FUNDAMENTAL ROLES IN KIDNEY CELL BIOLOGY THROUGH THE ACTION OF DNA METHYLATION, CHROMATIN MODIFICATION VIA EPIGENETIC REGULATORS AND NON-CODING RNA SPECIES. KIDNEY DISEASES, INCLUDING ACUTE KIDNEY INJURY, CHRONIC KIDNEY DISEASE, DIABETIC KIDNEY DISEASE AND RENAL FIBROSIS ARE MULTISTEP PROCESSES ASSOCIATED WITH NUMEROUS MOLECULAR ALTERATIONS EVEN IN INDIVIDUAL KIDNEY CELLS. EPIGENETIC ALTERATIONS, INCLUDING ANOMALOUS DNA METHYLATION, ABERRANT HISTONE ALTERATIONS AND CHANGES OF MICRORNA EXPRESSION ALL CONTRIBUTE TO KIDNEY PATHOGENESIS. THESE CHANGES ALTER THE GENOME-WIDE EPIGENETIC SIGNATURES AND DISRUPT ESSENTIAL PATHWAYS THAT PROTECT RENAL CELLS FROM UNCONTROLLED GROWTH, APOPTOSIS AND DEVELOPMENT OF OTHER RENAL ASSOCIATED SYNDROMES. MOLECULAR CHANGES IMPACT CELLULAR FUNCTION WITHIN KIDNEY CELLS AND ITS MICROENVIRONMENT TO DRIVE AND MAINTAIN DISEASE PHENOTYPE. IN THIS CHAPTER, WE BRIEFLY SUMMARIZE EPIGENETIC MECHANISMS IN FOUR KIDNEY DISEASES INCLUDING ACUTE KIDNEY INJURY, CHRONIC KIDNEY DISEASE, DIABETIC KIDNEY DISEASE AND RENAL FIBROSIS. WE PRIMARILY FOCUS ON CURRENT KNOWLEDGE ABOUT THE GENOME-WIDE PROFILING OF DNA METHYLATION AND HISTONE MODIFICATION, AND EPIGENETIC REGULATION ON SPECIFIC GENE(S) IN THE PATHOPHYSIOLOGY OF THESE DISEASES AND THE TRANSLATIONAL POTENTIAL OF IDENTIFYING NEW BIOMARKERS AND TREATMENT FOR PREVENTION AND THERAPY. INCORPORATING EPIGENOMIC TESTING INTO CLINICAL RESEARCH IS ESSENTIAL TO ELUCIDATE NOVEL EPIGENETIC BIOMARKERS AND DEVELOP PRECISION MEDICINE USING EMERGING THERAPIES. 2021 11 4250 29 METHYLATION-DEMETHYLATION DYNAMICS: IMPLICATIONS OF CHANGES IN ACUTE KIDNEY INJURY. OVER THE YEARS, THE EPIGENETIC LANDSCAPE HAS GROWN INCREASINGLY COMPLEX. UNTIL RECENTLY, METHYLATION OF DNA AND HISTONES WAS CONSIDERED ONE OF THE MOST IMPORTANT EPIGENETIC MODIFICATIONS. HOWEVER, WITH THE DISCOVERY OF ENZYMES INVOLVED IN THE DEMETHYLATION PROCESS, SEVERAL EXCITING PROSPECTS HAVE EMERGED THAT FOCUS ON THE DYNAMIC REGULATION OF METHYLATION AND ITS CRUCIAL ROLE IN DEVELOPMENT AND DISEASE. AN INTERPLAY OF THE METHYLATION-DEMETHYLATION MACHINERY CONTROLS THE PROCESS OF GENE EXPRESSION. SINCE ACUTE KIDNEY INJURY (AKI), A MAJOR RISK FACTOR FOR CHRONIC KIDNEY DISEASE AND DEATH, IS CHARACTERISED BY ABERRANT EXPRESSION OF GENES, UNDERSTANDING THE DYNAMICS OF METHYLATION AND DEMETHYLATION WILL PROVIDE NEW INSIGHTS INTO THE INTRICACIES OF THE DISEASE. RESEARCH ON EPIGENETICS IN AKI HAS ONLY MADE ITS MARK IN THE RECENT YEARS BUT HAS PROVIDED COMPELLING EVIDENCE THAT IMPLICATES THE INVOLVEMENT OF METHYLATION AND DEMETHYLATION CHANGES IN ITS PATHOPHYSIOLOGY. IN THIS REVIEW, WE EXPLORE THE ROLE OF METHYLATION AND DEMETHYLATION MACHINERY IN CELLULAR EPIGENETIC CONTROL AND FURTHER DISCUSS THE CONTRIBUTION OF METHYLOMIC CHANGES AND HISTONE MODIFICATIONS TO THE PATHOPHYSIOLOGY OF AKI. 2018 12 4668 22 NEW INSIGHTS INTO MOLECULAR MECHANISMS OF EPIGENETIC REGULATION IN KIDNEY DISEASE. THE NUMBER OF PATIENTS WITH KIDNEY FAILURE HAS INCREASED IN RECENT YEARS. DIFFERENT FACTORS CONTRIBUTE TO THE PROGRESSION OF CHRONIC KIDNEY DISEASE, INCLUDING GLOMERULAR SCLEROSIS, ATHEROSCLEROSIS OF THE RENAL ARTERIES AND TUBULOINTERSTITIAL FIBROSIS. TUBULOINTERSTITIAL INJURY IS INDUCED BY HYPOXIA AND OTHER INFLAMMATORY SIGNALS, LEADING TO FIBROBLAST ACTIVATION. TECHNOLOGICAL ADVANCES USING HIGH-THROUGHPUT SEQUENCING HAS ENABLED THE DETERMINATION OF THE EXPRESSION PROFILE OF ALMOST ALL GENES, REVEALING THAT GENE EXPRESSION IS INTRICATELY REGULATED BY DNA METHYLATION, HISTONE MODIFICATION, CHANGES IN CHROMOSOME CONFORMATION, LONG NON-CODING RNAS AND MICRORNAS. THESE EPIGENETIC MODIFICATIONS ARE STORED AS CELLULAR EPIGENETIC MEMORY. EPIGENETIC MEMORY LEADS TO ADULT-ONSET DISEASE OR AGEING IN THE LONG TERM AND MAY POSSIBLY PLAY AN IMPORTANT ROLE IN THE KIDNEY DISEASE PROCESS. HEREIN WE EMPHASIZE THE IMPORTANCE OF CLARIFYING THE MOLECULAR MECHANISMS UNDERLYING EPIGENETIC MODIFICATIONS BECAUSE THIS MAY LEAD TO THE DEVELOPMENT OF NEW THERAPEUTIC TARGETS IN KIDNEY DISEASE. 2016 13 2014 24 EPIGENETIC BIOMARKERS FOR THE DIAGNOSIS AND TREATMENT OF LIVER DISEASE. RESEARCH IN THE LAST DECADES HAS DEMONSTRATED THE RELEVANCE OF EPIGENETICS IN CONTROLLING GENE EXPRESSION TO MAINTAIN CELL HOMEOSTASIS, AND THE IMPORTANT ROLE PLAYED BY EPIGENOME ALTERATIONS IN DISEASE DEVELOPMENT. MOREOVER, THE REVERSIBILITY OF EPIGENETIC MARKS CAN BE HARNESSED AS A THERAPEUTIC STRATEGY, AND EPIGENETIC MARKS CAN BE USED AS DIAGNOSIS BIOMARKERS. EPIGENETIC ALTERATIONS IN DNA METHYLATION, HISTONE POST-TRANSLATIONAL MODIFICATIONS (PTMS), AND NON-CODING RNA (NCRNA) EXPRESSION HAVE BEEN ASSOCIATED WITH THE PROCESS OF HEPATOCARCINOGENESIS. HERE, WE SUMMARIZE EPIGENETIC ALTERATIONS INVOLVED IN THE PATHOGENESIS OF CHRONIC LIVER DISEASE (CLD), PARTICULARLY FOCUSING ON DNA METHYLATION. WE ALSO DISCUSS THEIR UTILITY AS EPIGENETIC BIOMARKERS IN LIQUID BIOPSY FOR THE DIAGNOSIS AND PROGNOSIS OF HEPATOCELLULAR CARCINOMA (HCC). FINALLY, WE DISCUSS THE POTENTIAL OF EPIGENETIC THERAPEUTIC STRATEGIES FOR HCC TREATMENT. 2021 14 2218 25 EPIGENETIC MODIFICATIONS IN FIBROTIC DISEASES: IMPLICATIONS FOR PATHOGENESIS AND PHARMACOLOGICAL TARGETS. ORGAN FIBROSIS IS A COMPLEX AND CHRONIC DISORDER THAT RESULTS FROM A VARIETY OF ACUTE INJURIES AND CONTRIBUTES TO THIRTY PERCENT OF NATURALLY OCCURRING DEATHS WORLDWIDE. THE MAIN FEATURE OF ORGAN FIBROSIS IS THE EXCESSIVE ACCUMULATION AND DEPOSIT OF EXTRACELLULAR MATRIX, THEREBY LEADING TO ORGAN DYSFUNCTION, LOSS OF ELASTICITY, AND DEVELOPMENT OF A RIGID ORGAN. ACCUMULATING EVIDENCE SHOWS THAT EPIGENETIC REMODELING, INCLUDING ABERRANT DNA METHYLATION AND NONCODING RNA EXPRESSION AS WELL AS HISTONE POST-TRANSLATIONAL MODIFICATIONS, PLAY IMPORTANT ROLES IN THE PATHOGENESIS OF FIBROSIS THROUGH THE REGULATION OF FIBROBLAST ACTIVATION, DIFFERENTIATION, AND APOPTOSIS, AS WELL AS COLLAGEN SYNTHESIS AND PROFIBROTIC GENE TRANSCRIPTION. IN THIS REVIEW, WE DISCUSS THE BASIC REGULATION OF DNA METHYLATION, NONCODING RNA EXPRESSION, AND HISTONE POST-TRANSLATIONAL MODIFICATION, AND THEIR PARTICIPATION IN THE PATHOGENESIS AND DEVELOPMENT OF ORGAN FIBROSIS. THIS REVIEW ALSO PROVIDES THE LATEST INSIGHTS INTO THE NOVEL BIOMARKERS AND THERAPEUTIC TARGETS FOR FIBROSIS THROUGH MODULATION OF EPIGENETIC REMODELING. 2015 15 3957 20 LONG NON-CODING RNAS AS EMERGING REGULATORS OF MIRNAS AND EPIGENETICS IN DIABETES-RELATED CHRONIC KIDNEY DISEASE. DIABETES IS ONE OF THE MAJOR CAUSE OF CHRONIC KIDNEY DISEASE (CKD), INCLUDING "DIABETIC NEPHROPATHY," AND IS AN INCREASINGLY PREVALENT ACCELERATOR OF THE PROGRESSION OF NON-DIABETIC FORMS OF CKD. THE LONG NON-CODING RNAS (LNCRNAS) HAVE COME INTO THE LIMELIGHT IN THE PAST FEW YEARS AS ONE OF THE EMERGING WEAPONS AGAINST CKD IN DIABETES. AVAILABLE DATA OVER THE PAST FEW YEARS DEMONSTRATE THE INTERACTION OF LNCRNAS WITH MIRNAS AND EPIGENETIC MACHINERY. INTERESTINGLY, THE EVOLVING DATA SUGGEST THAT LNCRNAS PLAY A VITAL ROLE IN DIABETES-ASSOCIATED CKD BY REGULATION OF EPIGENETIC ENZYMES SUCH AS DNA METHYLTRANSFERASE, HISTONE DEACETYLASES, AND HISTONE METHYLTRANSFERASES. LNCRNAS ARE ALSO ENGAGED IN THE REGULATION OF SEVERAL MIRNAS IN DIABETIC NEPHROPATHY. HENCE THIS REVIEW WILL ELABORATE ON THE ASSOCIATION BETWEEN LNCRNAS AND THEIR INTERACTION WITH EPIGENETIC REGULATORS INVOLVED IN DIFFERENT ASPECTS AND THUS THE PROGRESSION OF CKD IN DIABETES. 2022 16 3960 27 LONG NON-CODING RNAS: A DOUBLE-EDGED SWORD IN AGING KIDNEY AND RENAL DISEASE. AGING AS ONE OF INTRINSIC BIOLOGICAL PROCESSES IS A RISK FACTOR FOR MANY CHRONIC DISEASES. KIDNEY DISEASE IS A GLOBAL PROBLEM AND HEALTH CARE BURDEN WORLDWIDE. THE DIAGNOSIS OF KIDNEY DISEASE IS CURRENTLY BASED ON SERUM CREATININE AND UREA LEVELS. NOVEL BIOMARKERS MAY IMPROVE DIAGNOSTIC ACCURACY, THEREBY ALLOWING EARLY PREVENTION AND TREATMENT. OVER THE PAST FEW YEARS, ADVANCES IN GENOME ANALYSES HAVE IDENTIFIED AN EMERGING CLASS OF NONCODING RNAS THAT PLAY CRITICAL ROLES IN THE REGULATION OF GENE EXPRESSION AND EPIGENETIC REPROGRAMMING. LONG NONCODING RNAS (LNCRNAS) ARE PERVASIVELY TRANSCRIBED IN THE GENOME AND COULD BIND DNA, RNA AND PROTEIN. EMERGING EVIDENCE HAS DEMONSTRATED THAT LNCRNAS PLAYED AN IMPORTANT ROLE IN ALL STAGES OF KIDNEY DISEASE. TO DATE, ONLY SOME LNCRNAS WERE WELL IDENTIFIED AND CHARACTERIZED, BUT THE COMPLEXITY OF MULTILEVEL REGULATION OF TRANSCRIPTIONAL PROGRAMS INVOLVED IN THESE PROCESSES REMAINS UNDEFINED. IN THIS REVIEW, WE SUMMARIZED THE LNCRNA EXPRESSION PROFILING OF LARGE-SCALE IDENTIFIED LNCRNAS ON KIDNEY DISEASES INCLUDING ACUTE KIDNEY INJURY, CHRONIC KIDNEY DISEASE, DIABETIC NEPHROPATHY AND KIDNEY TRANSPLANTATION. WE FURTHER DISCUSSED A NUMBER OF ANNOTATED LNCRNAS LINKING WITH COMPLEX ETIOLOGY OF KIDNEY DISEASES. FINALLY, SEVERAL LNCRNAS WERE HIGHLIGHTED AS DIAGNOSTIC BIOMARKERS AND THERAPEUTIC TARGETS. TARGETING LNCRNAS MAY REPRESENT A PRECISE THERAPEUTIC STRATEGY FOR PROGRESSIVE RENAL FIBROSIS. 2021 17 2609 24 EPIGENETICS: A POTENTIAL KEY MECHANISM INVOLVED IN THE PATHOGENESIS OF CARDIORENAL SYNDROMES. EPIGENETICS IS DEFINED AS THE HERITABLE CHANGES IN GENE EXPRESSION PATTERNS WHICH ARE NOT DIRECTLY ENCODED BY MODIFICATIONS IN THE NUCLEOTIDE DNA SEQUENCE OF THE GENOME, INCLUDING HIGHER ORDER CHROMATIN ORGANIZATION, DNA METHYLATION, CYTOSINE MODIFICATIONS, COVALENT HISTONE TAIL MODIFICATIONS, AND SHORT NON-CODING RNA MOLECULES. RECENTLY, MUCH ATTENTION HAS BEEN PAID TO THE ROLE AND THE FUNCTION OF EPIGENETICS AND EPIMUTATIONS IN THE CELLULAR AND SUBCELLULAR PATHWAYS AND IN THE REGULATION OF GENES IN THE SETTING OF BOTH KIDNEY AND CARDIOVASCULAR DISEASE. INDEED, DEREGULATION OF HISTONE ALTERATIONS HAS BEEN HIGHLIGHTED IN A LARGE SPECTRUM OF RENAL AND CARDIAC DISEASE, INCLUDING CHRONIC AND ACUTE RENAL INJURY, RENAL AND CARDIAC FIBROSIS, CARDIAC HYPERTROPHY AND FAILURE, KIDNEY CONGENITAL ANOMALIES, RENAL HYPOXIA, AND DIABETIC RENAL COMPLICATIONS. NEVERTHELESS, THE ROLE OF EPIGENETICS IN THE PATHOGENESIS AND PATHOPHYSIOLOGY OF CARDIORENAL SYNDROMES IS CURRENTLY UNDEREXPLORED. GIVEN THE SIGNIFICANT CLINICAL RELEVANCE OF HEART-KIDNEY CROSSTALK, EFFORTS IN THE RESEARCH FOR NEW ACTION MECHANISMS CONCURRENTLY OPERATING IN BOTH PATHOLOGIES ARE THUS OF MAXIMUM INTEREST. THIS REVIEW FOCUSES ON EPIGENETIC MECHANISMS INVOLVED IN HEART AND KIDNEY DISEASE, AND THEIR POSSIBLE ROLE IN THE SETTING OF CARDIORENAL SYNDROMES. 2018 18 6092 27 THE EFFECTS OF EPIGENETIC MODIFICATION ON THE OCCURRENCE AND PROGRESSION OF LIVER DISEASES AND THE INVOLVED MECHANISM. INTRODUCTION: EPIGENETIC MODIFICATION IS A TYPE OF GENE EXPRESSION AND REGULATION THAT DOES NOT INVOLVE CHANGES IN DNA SEQUENCES. AN INCREASING NUMBER OF STUDIES HAVE PROVEN THAT EPIGENETIC MODIFICATIONS PLAY AN IMPORTANT ROLE IN THE OCCURRENCE AND PROGRESSION OF LIVER DISEASES THROUGH THE GENE REGULATION AND PROTEIN EXPRESSIONS OF HEPATOCELLULAR LIPID METABOLISM, INFLAMMATORY REACTION, CELL PROLIFERATION, AND ACTIVATION, ETC.AREAS COVERED: IN THIS STUDY, WE ELABORATED AND ANALYZED THE UNDERLYING FUNCTIONAL MECHANISM OF EPIGENETIC MODIFICATION IN ALCOHOLIC LIVER DISEASE (ALD), NONALCOHOLIC FATTY LIVER DISEASE (NAFLD), LIVER FIBROSIS (LF), VIRAL HEPATITIS, HEPATOCELLULAR CARCINOMA (HCC), AND RESEARCH PROGRESS OF RECENT YEARS.EXPERT OPINION: THE FURTHER UNDERSTANDING OF EPIGENETIC MECHANISMS THAT CAN REGULATE GENE EXPRESSION AND CELL PHENOTYPE LEADS TO NEW INSIGHTS IN EPIGENETIC CONTROL OF CHRONIC LIVER DISEASE. CURRENTLY, HEPATOLOGISTS ARE EXPLORING THE ROLE OF DNA METHYLATION, HISTONE/CHROMATIN MODIFICATION, AND NON-CODING RNA IN SPECIFIC LIVER PATHOLOGY. THESE FINDINGS HAVE LED TO ADVANCES IN DIRECT EPIGENETIC BIOMARKER TESTING OF PATIENT TISSUE OR BODY FLUID SPECIMENS, AS WELL AS QUANTITATIVE ANALYSIS. BASED ON THESE FINDINGS, DRUG VALIDATION OF SOME TARGETS INVOLVED IN THE EPIGENETIC MECHANISM OF LIVER DISEASE IS GRADUALLY BEING CARRIED OUT CLINICALLY. 2020 19 1597 21 DNA METHYLATION REGULATED GENE EXPRESSION IN ORGAN FIBROSIS. DNA METHYLATION IS A MAJOR EPIGENETIC MECHANISM TO REGULATE GENE EXPRESSION. EPIGENETIC REGULATION, INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS AND RNA INTERFERENCE, RESULTS IN HERITABLE CHANGES IN GENE EXPRESSION INDEPENDENT OF ALTERATIONS IN DNA SEQUENCE. EPIGENETIC REGULATION OFTEN OCCURS IN RESPONSE TO AGING AND ENVIRONMENT STIMULI, INCLUDING EXPOSURES AND DIET. STUDIES HAVE SHOWN THAT DNA METHYLATION IS CRITICAL IN THE PATHOGENESIS OF FIBROSIS INVOLVING MULTIPLE ORGAN SYSTEMS, CONTRIBUTING TO SIGNIFICANT MORBIDITY AND MORTALITY. ABERRANT DNA METHYLATION CAN SILENCE OR ACTIVATE GENE EXPRESSION PATTERNS THAT DRIVE THE FIBROSIS PROCESS. FIBROSIS IS A PATHOLOGICAL WOUND HEALING PROCESS IN RESPONSE TO CHRONIC INJURY. IT IS CHARACTERIZED BY EXCESSIVE EXTRACELLULAR MATRIX PRODUCTION AND ACCUMULATION, WHICH EVENTUALLY AFFECTS ORGAN ARCHITECTURE AND RESULTS IN ORGAN FAILURE. FIBROSIS CAN AFFECT A WIDE RANGE OF ORGANS, INCLUDING THE HEART AND LUNGS, AND HAVE LIMITED THERAPEUTIC OPTIONS. DNA METHYLATION, LIKE OTHER EPIGENETIC PROCESS, IS REVERSIBLE, THEREFORE REGARDED AS ATTRACTIVE THERAPEUTIC INTERVENTIONS. ALTHOUGH EPIGENETIC MECHANISMS ARE HIGHLY INTERACTIVE AND OFTEN REINFORCING, THIS REVIEW DISCUSSES DNA METHYLATION-DEPENDENT MECHANISMS IN THE PATHOGENESIS OF ORGAN FIBROSIS, WITH FOCUS ON CARDIAC AND PULMONARY FIBROSIS. WE DISCUSS SPECIFIC PRO- AND ANTI-FIBROTIC GENES AND PATHWAYS REGULATED BY DNA METHYLATION IN ORGAN FIBROSIS; WE FURTHER HIGHLIGHT THE POTENTIAL BENEFITS AND SIDE-EFFECTS OF EPIGENETIC THERAPIES IN FIBROTIC DISORDERS. 2017 20 607 22 BEYOND GENETICS: EPIGENETIC CODE IN CHRONIC KIDNEY DISEASE. EPIGENETICS REFERS TO A HERITABLE CHANGE IN THE PATTERN OF GENE EXPRESSION THAT IS MEDIATED BY A MECHANISM SPECIFICALLY NOT DUE TO ALTERATIONS IN THE PRIMARY NUCLEOTIDE SEQUENCE. WELL-KNOWN EPIGENETIC MECHANISMS ENCOMPASS DNA METHYLATION, CHROMATIN REMODELING (HISTONE MODIFICATIONS), AND RNA INTERFERENCE. FUNCTIONALLY, EPIGENETICS PROVIDES AN EXTRA LAYER OF TRANSCRIPTIONAL CONTROL AND PLAYS A CRUCIAL ROLE IN NORMAL PHYSIOLOGICAL DEVELOPMENT, AS WELL AS IN PATHOLOGICAL CONDITIONS. ABERRANT DNA METHYLATION IS IMPLICATED IN IMMUNE DYSFUNCTION, INFLAMMATION, AND INSULIN RESISTANCE. EPIGENETIC CHANGES MAY BE RESPONSIBLE FOR 'METABOLIC MEMORY' AND DEVELOPMENT OF MICRO- AND MACROVASCULAR COMPLICATIONS OF DIABETES. MICRORNAS ARE CRITICAL IN THE MAINTENANCE OF GLOMERULAR HOMEOSTASIS AND HENCE RNA INTERFERENCE MAY BE IMPORTANT IN THE PROGRESSION OF RENAL DISEASE. RECENT STUDIES HAVE SHOWN THAT EPIGENETIC MODIFICATIONS ORCHESTRATE THE EPITHELIAL-MESENCHYMAL TRANSITION AND EVENTUALLY FIBROSIS OF THE RENAL TISSUE. OXIDATIVE STRESS, INFLAMMATION, HYPERHOMOCYSTEINEMIA, AND UREMIC TOXINS COULD INDUCE EPIMUTATIONS IN CHRONIC KIDNEY DISEASE. EPIGENETIC ALTERATIONS ARE ASSOCIATED WITH INFLAMMATION AND CARDIOVASCULAR DISEASE IN PATIENTS WITH CHRONIC KIDNEY DISEASE. REVERSIBLE NATURE OF THE EPIGENETIC CHANGES GIVES A UNIQUE OPPORTUNITY TO HALT OR EVEN REVERSE THE DISEASE PROCESS THROUGH TARGETED THERAPEUTIC STRATEGIES. 2011