1 5548 109 ROLE OF EPIGENETIC REPROGRAMMING OF HOST GENES IN BACTERIAL PATHOGENESIS. THE GENOMES ARE REGULARLY TARGETED BY EPIGENETIC REGULATORY MECHANISMS (DNA METHYLATION, HISTONE MODIFICATIONS, BINDING OF REGULATORY PROTEINS) IN INFECTED CELLS. IN ADDITION, PROTEINS ENCODED BY MICROBIAL GENOMES MAY DISTURB THE ACTION OF A SET OF CELLULAR PROMOTERS BY INTERACTING WITH THE SAME EPI-REGULATORY MACHINERY. THE OUTCOME OF THIS MAY RESULT IN EPIGENETIC DYSREGULATION AND SUBSEQUENT CELLULAR DYSFUNCTIONS THAT MAY MANIFEST IN OR CONTRIBUTE TO THE DEVELOPMENT OF PATHOLOGICAL CHANGES. HOW EPIGENETIC METHYLATION DECORATIONS ON DNA AND HISTONES ARE STARTED AND ESTABLISHED REMAINS LARGELY UNKNOWN. THE INHERITED NATURE OF THESE PROCESSES IN REGULATION OF GENES SUGGESTS THAT THEY COULD PLAY KEY ROLES IN CHRONIC DISEASES ASSOCIATED WITH MICROBIAL PERSISTENCE; THEY MIGHT ALSO EXPLAIN SO-CALLED HIT-AND-RUN PHENOMENA IN INFECTIOUS DISEASE PATHOGENESIS. MICROBES INFECTING MAMMALS MAY CAUSE DISEASES BY CAUSING HYPER-METHYLATION OF KEY CELLULAR PROMOTERS AT CPG DI-NUCLEOTIDES AND MAY INDUCE PATHOLOGICAL CHANGES BY EPIGENETIC REPROGRAMMING OF HOST CELLS THEY ARE INTERACTING WITH ELUCIDATION OF THE EPIGENETIC CONSEQUENCES OF MICROBE-HOST INTERACTIONS MAY HAVE IMPORTANT THERAPEUTIC IMPLICATIONS BECAUSE EPIGENETIC PROCESSES CAN BE REVERTED AND ELIMINATION OF MICROBES INDUCING PATHO-EPIGENETIC CHANGES MAY PREVENT DISEASE DEVELOPMENT. 2013 2 2399 55 EPIGENETIC REPROGRAMMING OF HOST GENES IN VIRAL AND MICROBIAL PATHOGENESIS. ONE OF THE KEY QUESTIONS IN THE STUDY OF MAMMALIAN GENE REGULATION IS HOW EPIGENETIC METHYLATION PATTERNS ON HISTONES AND DNA ARE INITIATED AND ESTABLISHED. THESE STABLE, HERITABLE, COVALENT MODIFICATIONS ARE LARGELY ASSOCIATED WITH THE REPRESSION OR SILENCING OF GENE TRANSCRIPTION, AND WHEN DEREGULATED CAN BE INVOLVED IN THE DEVELOPMENT OF HUMAN DISEASES SUCH AS CANCER. THIS ARTICLE REVIEWS EXAMPLES OF VIRUSES AND BACTERIA KNOWN OR THOUGHT TO INDUCE EPIGENETIC CHANGES IN HOST CELLS, AND HOW THIS MIGHT CONTRIBUTE TO DISEASE. THE HERITABLE NATURE OF THESE PROCESSES IN GENE REGULATION SUGGESTS THAT THEY COULD PLAY IMPORTANT ROLES IN CHRONIC DISEASES ASSOCIATED WITH MICROBIAL PERSISTENCE; THEY MIGHT ALSO EXPLAIN SO-CALLED 'HIT-AND-RUN' PHENOMENA IN INFECTIOUS DISEASE PATHOGENESIS. 2010 3 2338 33 EPIGENETIC REGULATION OF INFLAMMATORY SIGNALING AND INFLAMMATION-INDUCED CANCER. EPIGENETICS COMPRISE A DIVERSE ARRAY OF REVERSIBLE AND DYNAMIC MODIFICATIONS TO THE CELL'S GENOME WITHOUT IMPLICATING ANY DNA SEQUENCE ALTERATIONS. BOTH THE EXTERNAL ENVIRONMENT SURROUNDING THE ORGANISM, AS WELL AS THE INTERNAL MICROENVIRONMENT OF CELLS AND TISSUES, CONTRIBUTE TO THESE EPIGENETIC PROCESSES THAT PLAY CRITICAL ROLES IN CELL FATE SPECIFICATION AND ORGANISMAL DEVELOPMENT. ON THE OTHER HAND, DYSREGULATION OF EPIGENETIC ACTIVITIES CAN INITIATE AND SUSTAIN CARCINOGENESIS, WHICH IS OFTEN AUGMENTED BY INFLAMMATION. CHRONIC INFLAMMATION, ONE OF THE MAJOR HALLMARKS OF CANCER, STEMS FROM PROINFLAMMATORY CYTOKINES THAT ARE SECRETED BY TUMOR AND TUMOR-ASSOCIATED CELLS IN THE TUMOR MICROENVIRONMENT. AT THE SAME TIME, INFLAMMATORY SIGNALING CAN ESTABLISH POSITIVE AND NEGATIVE FEEDBACK CIRCUITS WITH CHROMATIN TO MODULATE CHANGES IN THE GLOBAL EPIGENETIC LANDSCAPE. IN THIS REVIEW, WE PROVIDE AN IN-DEPTH DISCUSSION OF THE INTERCONNECTED CROSSTALK BETWEEN EPIGENETICS AND INFLAMMATION, SPECIFICALLY HOW EPIGENETIC MECHANISMS AT DIFFERENT HIERARCHICAL LEVELS OF THE GENOME CONTROL INFLAMMATORY GENE TRANSCRIPTION, WHICH IN TURN ENACT CHANGES WITHIN THE CELL'S EPIGENOMIC PROFILE, ESPECIALLY IN THE CONTEXT OF INFLAMMATION-INDUCED CANCER. 2022 4 2501 37 EPIGENETICS AND ITS ROLE IN PERIODONTAL DISEASES: A STATE-OF-THE-ART REVIEW. THE IMMUNE RESPONSE TO ORAL BACTERIA AND THE SUBSEQUENT ACTIVATION OF INFLAMMATORY SIGNALING IS NOT ONLY DEPENDENT ON GENETIC FACTORS. THE IMPORTANCE OF SO-CALLED EPIGENETIC MECHANISMS PRESENTS ADDITIONAL REGULATORY PATHWAYS OF GENES INVOLVED IN MAINTAINING CHRONIC INFLAMMATION, INCLUDING GINGIVITIS AND PERIODONTITIS. THE TERM EPIGENETICS RELATES TO CHANGES IN GENE EXPRESSION THAT ARE NOT ENCODED IN THE DNA SEQUENCE ITSELF AND INCLUDE CHEMICAL ALTERATIONS OF DNA AND ITS ASSOCIATED PROTEINS. THESE CHANGES LEAD TO REMODELING OF THE CHROMATIN AND SUBSEQUENT ACTIVATION OR INACTIVATION OF A GENE. EPIGENETIC MECHANISMS HAVE BEEN FOUND TO CONTRIBUTE TO DISEASE, INCLUDING CANCER AND AUTOIMMUNE OR INFLAMMATORY DISEASES. IN THIS STATE-OF-THE ART REVIEW, THE AUTHORS PROVIDE THE LATEST FINDINGS ON THE INVOLVEMENT OF EPIGENETIC MODIFICATIONS IN THE DEVELOPMENT OF PERIODONTAL DISEASE AND PRESENT EMERGING THERAPEUTIC STRATEGIES AIMED AT EPIGENETIC TARGETS (EPIDRUGS) ASSOCIATED WITH THE DISRUPTION OF TISSUE HOMEOSTASIS AND THE DEVELOPMENT OF PERIODONTITIS. 2015 5 5325 37 PULMONARY PATHOGEN-INDUCED EPIGENETIC MODIFICATIONS. EPIGENETICS GENERALLY INVOLVES GENETIC CONTROL BY FACTORS OTHER THAN OUR OWN DNA SEQUENCE. RECENT RESEARCH HAS FOCUSED ON DELINEATING THE MECHANISMS OF TWO MAJOR EPIGENETIC PHENOMENA: DNA METHYLATION AND HISTONE MODIFICATION. AS EPIGENETICS INVOLVES MANY CELLULAR PROCESSES, IT IS NO SURPRISE THAT IT CAN ALSO INFLUENCE DISEASE-ASSOCIATED GENE EXPRESSION. A DIRECT LINK BETWEEN RESPIRATORY INFECTIONS, HOST CELL EPIGENETIC REGULATIONS, AND CHRONIC LUNG DISEASES IS STILL UNKNOWN. RECENT STUDIES HAVE REVEALED BACTERIUM- OR VIRUS-INDUCED EPIGENETIC CHANGES IN THE HOST CELLS. IN THIS REVIEW, WE FOCUSED ON RESPIRATORY PATHOGENS (VIRUSES, BACTERIA, AND FUNGI) INDUCED EPIGENETIC MODULATIONS (DNA METHYLATION AND HISTONE MODIFICATION) THAT MAY CONTRIBUTE TO LUNG DISEASE PATHOPHYSIOLOGY BY PROMOTING HOST DEFENSE OR ALLOWING PATHOGEN PERSISTENCE. 2023 6 3703 26 INFLAMMATORY SIGNALLING AS MEDIATOR OF EPIGENETIC MODULATION IN TISSUE-SPECIFIC CHRONIC INFLAMMATION. RECENT SUCCESSES OF THERAPEUTIC INTERVENTION IN CHRONIC INFLAMMATORY DISEASES USING EPIGENETIC MODIFIERS SUCH AS HISTONE DEACETYLASE INHIBITORS AND INHIBITORS OF DNA METHYLATION SUGGEST THAT EPIGENETIC REPROGRAMMING PLAYS A ROLE IN THE AETIOLOGY OF THESE DISEASES. THE EPIGENETIC SIGNATURE OF A GIVEN IMMUNE CELL IS REFLECTED IN THE HISTORY OF MODIFICATIONS FROM DIFFERENT SIGNALS THE CELL HAS BEEN SUBJECTED TO DURING DIFFERENTIATION. LIKE OTHER CELLS, DIFFERENTIATING IMMUNE CELLS ARE DEPENDENT ON A COMPLEX COMBINATION OF INTER- AND INTRACELL SIGNALLING AS WELL AS TRANSCRIPTION MACHINERIES TO MODULATE THEIR EPIGENOMES IN ORDER TO MEDIATE DIFFERENTIATION. DESPITE EXTENSIVE RESEARCH INTO THESE PROCESSES, THE LINK BETWEEN CELLULAR SIGNALLING AND EPIGENETIC MODULATION REMAINS POORLY UNDERSTOOD. HERE, WE REVIEW RECENT PROGRESS AND DISCUSS KEY FACTORS DRIVING EPIGENETIC MODULATION IN CHRONIC INFLAMMATION. 2009 7 6344 28 THE ROLE OF EPIGENETICS IN AGING AND AUTOIMMUNITY. THE DECLINE IN IMMUNOCOMPETENCE WITH AGE IS ACCOMPANIED BY THE INCREASE IN THE INCIDENCE OF AUTOIMMUNE DISEASES. AGING OF THE IMMUNE SYSTEM, OR IMMUNOSENESCENCE, IS CHARACTERIZED BY A DECLINE OF BOTH T AND B CELL FUNCTION, AND PARADOXICALLY THE PRESENCE OF LOW-GRADE CHRONIC INFLAMMATION. THERE IS GROWING EVIDENCE THAT EPIGENETICS, THE STUDY OF INHERITED CHANGES IN GENE EXPRESSION THAT ARE NOT ENCODED BY THE DNA SEQUENCE ITSELF, CHANGES WITH AGING. INTERESTINGLY, EMERGING EVIDENCE SUGGESTS A KEY ROLE FOR EPIGENETICS IN HUMAN PATHOLOGIES, INCLUDING INFLAMMATORY AND NEOPLASTIC DISORDERS. HERE, WE WILL REVIEW THE POTENTIAL MECHANISMS THAT CONTRIBUTE TO THE INCREASE IN AUTOIMMUNE RESPONSES IN AGING. IN PARTICULAR, WE WILL DISCUSS HOW EPIGENETIC ALTERATIONS, ESPECIALLY DNA METHYLATION AND HISTONE ACETYLATION, ARE ACCUMULATED DURING AGING AND HOW THESE EVENTS CONTRIBUTE TO AUTOIMMUNITY RISK. 2010 8 2070 26 EPIGENETIC CONTROL OF SKIN IMMUNITY. EPIGENETICS HAS BEEN WELL UNDERSTOOD FOR ITS ROLE IN CELL DEVELOPMENT; HOWEVER, IT IS NOW KNOWN TO REGULATE MANY PROCESSES INVOLVED IN IMMUNE CELL ACTIVATION IN A VARIETY OF CELLS. THE SKIN MAINTAINS HOMEOSTASIS VIA CROSSTALK BETWEEN IMMUNE AND NON-IMMUNE CELLS. DISRUPTION OF NORMAL EPIGENETIC REGULATION IN THESE CELLS MAY ALTER THE TRANSCRIPTION OF IMMUNE-REGULATORY FACTORS AND AFFECT THE IMMUNOLOGICAL BALANCE IN THE SKIN. THIS REVIEW SUMMARIZES RECENT EVIDENCE FOR THE EPIGENETIC REGULATION OF SKIN IMMUNITY. MUCH OF WHAT IS KNOWN ABOUT EPIGENETIC INVOLVEMENT IN SKIN IMMUNITY IS ASSOCIATED WITH DNA METHYLATION. THIS REVIEW FOCUSES ON EPIGENETIC REGULATION OF HISTONE MODIFICATION AND CHROMATIN REMODELING AND DESCRIBES THEIR ROLE IN THE TRANSCRIPTIONAL REGULATION OF IMMUNE-REGULATORY FACTORS. WHILE MUCH IS STILL UNKNOWN REGARDING THE REGULATION OF SKIN IMMUNITY VIA HISTONE MODIFICATION OR CHROMATIN REMODELING, THESE PROCESSES MAY UNDERLIE THE PATHOGENESIS OF CHRONIC CUTANEOUS IMMUNE DISORDERS. 2023 9 4392 33 MODIFIABLE RISK FACTORS IN PERIODONTAL DISEASE: EPIGENETIC REGULATION OF GENE EXPRESSION IN THE INFLAMMATORY RESPONSE. EPIGENETICS AS A MODIFIABLE RISK FACTOR IN PERIODONTAL DISEASES HAS BEEN INVESTIGATED IN LIGHT OF THE CURRENT KNOWLEDGE OF HOW CHRONIC INFECTION AND INFLAMMATION CAN AFFECT GENE-SPECIFIC EPIGENETIC REPROGRAMMING IN PERIODONTAL TISSUES. EPIGENOMIC PROGRAMMING MIGHT BE PARTICULARLY SENSITIVE TO ENVIRONMENTAL INFLUENCES, AND A COMBINATION OF PHYSIOLOGICAL STRESSORS AND ENVIRONMENTAL EXPOSURES APPEARS TO AFFECT THE EPIGENOMIC PROGRAM ACQUIRED BY A CELL DURING DIFFERENTIATION AND THROUGHOUT THE CELLULAR LINEAGE LIFESPAN. VIRAL AND BACTERIAL INFECTIONS CAN ESTABLISH SEVERAL TYPES OF EPIGENETIC MODIFICATIONS, WHICH SOMETIMES ENGAGE IN A COMPLEX EPIGENETIC CROSSTALK ALSO REFLECTING IN THE ESTABLISHMENT AND PROGRESS OF PERIODONTAL DISEASES. THE INFLAMMATORY AND METABOLIC STATES OF THE PERIODONTAL TISSUES ARE DRIVEN BY THE INFECTIOUS STIMULI, AND THE MAGNITUDE OF THE CELLULAR AND MOLECULAR SIGNATURE RESPONSE IS FURTHER DICTATED BY THE HOST GENETIC AND EPIGENETIC TRAITS ASSOCIATED WITH VARIOUS SYSTEMIC EXPOSURES, INCLUDING SMOKING, OBESITY AND DIABETES/HYPERGLYCEMIA. THIS REVIEW DISCUSSES THE ADVANCES IN EPIGENETICS, FOCUSING ON THE ROLE OF DNA METHYLATION IN THE PATHOGENESIS OF PERIODONTAL DISEASE AND THE POTENTIAL OF EPIGENETIC THERAPY. 2014 10 2854 33 FROM HEPATITIS TO HEPATOCELLULAR CARCINOMA: A PROPOSED MODEL FOR CROSS-TALK BETWEEN INFLAMMATION AND EPIGENETIC MECHANISMS. INFLAMMATION REPRESENTS THE BODY'S NATURAL RESPONSE TO TISSUE DAMAGE; HOWEVER, CHRONIC INFLAMMATION MAY ACTIVATE CELL PROLIFERATION AND INDUCE DEREGULATION OF CELL DEATH IN AFFECTED TISSUES. CHRONIC INFLAMMATION IS AN IMPORTANT FACTOR IN THE DEVELOPMENT OF HEPATOCELLULAR CARCINOMA (HCC), ALTHOUGH THE PRECISE UNDERLYING MECHANISM REMAINS UNKNOWN. EPIGENETIC EVENTS, WHICH ARE CONSIDERED KEY MECHANISMS IN THE REGULATION OF GENE ACTIVITY STATES, ARE ALSO COMMONLY DEREGULATED IN HCC. HERE, WE REVIEW THE EVIDENCE THAT CHRONIC INFLAMMATION MIGHT DEREGULATE EPIGENETIC PROCESSES, THUS PROMOTING ONCOGENIC TRANSFORMATION, AND WE PROPOSE A WORKING HYPOTHESIS THAT EPIGENETIC DEREGULATION IS AN UNDERLYING MECHANISM BY WHICH INFLAMMATION MIGHT PROMOTE HCC DEVELOPMENT. IN THIS SCENARIO, DIFFERENT COMPONENTS OF THE INFLAMMATORY RESPONSE MIGHT DIRECTLY AND INDIRECTLY INDUCE CHANGES IN EPIGENETIC MACHINERIES ('EPIGENETIC SWITCH'), INCLUDING THOSE INVOLVED IN SETTING AND PROPAGATING NORMAL PATTERNS OF DNA METHYLATION, HISTONE MODIFICATIONS AND NON-CODING RNAS IN HEPATOCYTES. WE DISCUSS THE POSSIBILITY THAT SELF-REINFORCING CROSS-TALK BETWEEN INFLAMMATION AND EPIGENETIC MECHANISMS MIGHT AMPLIFY INFLAMMATORY SIGNALS AND MAINTAIN A CHRONIC STATE OF INFLAMMATION CULMINATING IN CANCER DEVELOPMENT. THE POTENTIAL ROLE OF INFLAMMATION-EPIGENOME INTERACTIONS IN THE EMERGENCE AND MAINTENANCE OF CANCER STEM CELLS IS ALSO DISCUSSED. 2012 11 6886 33 [ROLE OF EPIGENETIC MODIFICATION IN HIGHER BRAIN DYSFUNCTION AND AGING]. EPIGENETIC MECHANISMS TYPICALLY INVOLVE HERITABLE ALTERATIONS IN CHROMATIN STRUCTURE, WHICH, IN TURN, REGULATE GENE EXPRESSION. FUNDAMENTAL INSIGHTS ABOUT EPIGENETIC HERITABILITY HAVE COME FROM STUDIES OF CELL DIVISION AND DEVELOPMENT. HOWEVER, THERE IS INCREASING EVIDENCE THAT THE REGULATION OF CHROMATIN STRUCTURE THROUGH HISTONE MODIFICATIONS AND DNA METHYLATION MIGHT MEDIATE THE EXPRESSION OF KEY GENES INVOLVED IN ACQUIRED CHRONIC DISORDERS. THIS IDEA IS FASCINATING BECAUSE SIMILAR MECHANISMS ARE USED FOR TRIGGERING AND STORING LONG-TERM MEMORIES AT THE CELLULAR LEVEL DURING, FOR EXAMPLE, HIGHER-BRAIN DYSFUNCTION, STRESS DISEASE, DRUG DEPENDENCE, AGING, AND CHRONIC PAIN. THIS REVIEW WILL EXPLORE THE MOST CURRENT ISSUES IN THE FIELD OF EPIGENETICS, WITH A FOCUS ON NEXT LEVELS OF TRANSCRIPTIONAL MECHANISMS UNDERLYING AGING, ENRICHED ENVIRONMENT AND DRUG ADDICTION. EPIGENETIC MECHANISMS, WHICH ARE KEY CELLULAR AND MOLECULAR PROCESSES THAT INTEGRATE DIVERSE ENVIRONMENTAL STIMULI TO EXERT POTENT AND OFTEN LONG-LASTING CHANGES IN GENE EXPRESSION THROUGH THE REGULATION OF CHROMATIN STRUCTURE, CONTRIBUTE TO TRANSCRIPTIONAL AND BEHAVIORAL CHANGES. 2012 12 5932 31 TARGETING EPIGENETIC REGULATORS FOR INFLAMMATION: MECHANISMS AND INTERVENTION THERAPY. EMERGING EVIDENCE INDICATES THAT RESOLUTION OF INFLAMMATION IS A CRITICAL AND DYNAMIC ENDOGENOUS PROCESS FOR HOST TISSUES DEFENDING AGAINST EXTERNAL INVASIVE PATHOGENS OR INTERNAL TISSUE INJURY. IT HAS LONG BEEN KNOWN THAT AUTOIMMUNE DISEASES AND CHRONIC INFLAMMATORY DISORDERS ARE CHARACTERIZED BY DYSREGULATED IMMUNE RESPONSES, LEADING TO EXCESSIVE AND UNCONTROL TISSUE INFLAMMATION. THE DYSREGULATION OF EPIGENETIC ALTERATIONS INCLUDING DNA METHYLATION, POSTTRANSLATIONAL MODIFICATIONS TO HISTONE PROTEINS, AND NONCODING RNA EXPRESSION HAS BEEN IMPLICATED IN A HOST OF INFLAMMATORY DISORDERS AND THE IMMUNE SYSTEM. THE INFLAMMATORY RESPONSE IS CONSIDERED AS A CRITICAL TRIGGER OF EPIGENETIC ALTERATIONS THAT IN TURN INTERCEDE INFLAMMATORY ACTIONS. THUS, UNDERSTANDING THE MOLECULAR MECHANISM THAT DICTATES THE OUTCOME OF TARGETING EPIGENETIC REGULATORS FOR INFLAMMATORY DISEASE IS REQUIRED FOR INFLAMMATION RESOLUTION. IN THIS ARTICLE, WE ELUCIDATE THE CRITICAL ROLE OF THE NUCLEAR FACTOR-KAPPAB SIGNALING PATHWAY, JAK/STAT SIGNALING PATHWAY, AND THE NLRP3 INFLAMMASOME IN CHRONIC INFLAMMATORY DISEASES. AND WE FORMULATE THE RELATIONSHIP BETWEEN INFLAMMATION, CORONAVIRUS DISEASE 2019, AND HUMAN CANCERS. ADDITIONALLY, WE REVIEW THE MECHANISM OF EPIGENETIC MODIFICATIONS INVOLVED IN INFLAMMATION AND INNATE IMMUNE CELLS. ALL THAT MATTERS IS THAT WE PROPOSE AND DISCUSS THE REJUVENATION POTENTIAL OF INTERVENTIONS THAT TARGET EPIGENETIC REGULATORS AND REGULATORY MECHANISMS FOR CHRONIC INFLAMMATION-ASSOCIATED DISEASES TO IMPROVE THERAPEUTIC OUTCOMES. 2022 13 2532 32 EPIGENETICS IN ATHEROSCLEROSIS AND INFLAMMATION. ATHEROSCLEROSIS IS A MULTIFACTORIAL DISEASE WITH A SEVERE BURDEN ON WESTERN SOCIETY. RECENT INSIGHTS INTO THE PATHOGENESIS OF ATHEROSCLEROSIS UNDERSCORE THE IMPORTANCE OF CHRONIC INFLAMMATION IN BOTH THE INITIATION AND PROGRESSION OF VASCULAR REMODELLING. EXPRESSION OF IMMUNOREGULATORY MOLECULES BY VASCULAR WALL COMPONENTS WITHIN THE ATHEROSCLEROTIC LESIONS IS ACCORDINGLY THOUGHT TO CONTRIBUTE TO THE ONGOING INFLAMMATORY PROCESS. BESIDES GENE REGULATORY PROTEINS (TRANSCRIPTION FACTORS), EPIGENETIC MECHANISMS ALSO PLAY AN ESSENTIAL AND FUNDAMENTAL ROLE IN THE TRANSCRIPTIONAL CONTROL OF GENE EXPRESSION. THESE EPIGENETIC MECHANISMS CHANGE THE ACCESSIBILITY OF CHROMATIN BY DNA METHYLATION AND HISTONE MODIFICATIONS. EPIGENETIC MODULATORS ARE THUS CRITICALLY INVOLVED IN THE REGULATION OF VASCULAR, IMMUNE AND TISSUE-SPECIFIC GENE EXPRESSION WITHIN THE ATHEROSCLEROTIC LESION. IMPORTANTLY, EPIGENETIC PROCESSES ARE REVERSIBLE AND MAY PROVIDE AN EXCELLENT THERAPEUTIC TARGET. THE CONCEPT OF EPIGENETIC REGULATION IS GRADUALLY BEING RECOGNIZED AS AN IMPORTANT FACTOR IN THE PATHOGENESIS OF ATHEROSCLEROSIS. RECENT RESEARCH PROVIDES AN ESSENTIAL LINK BETWEEN INFLAMMATION AND REPROGRAMMING OF THE EPIGENOME. IN THIS REVIEW WE THEREFORE DISCUSS THE BASIS OF EPIGENETIC REGULATION - AND THE CONTRIBUTION THEREOF IN THE REGULATION OF INFLAMMATORY PROCESSES IN GENERAL AND DURING ATHEROSCLEROSIS IN PARTICULAR. MOREOVER WE HIGHLIGHT POTENTIAL THERAPEUTIC INTERVENTIONS BASED ON EPIGENETIC MECHANISMS. 2010 14 1606 35 DNA METHYLATION, BACTERIA AND AIRWAY INFLAMMATION: LATEST INSIGHTS. PURPOSE OF REVIEW: DNA METHYLATION IS AN EPIGENETIC MECHANISM THAT HAS BEEN IMPLICATED IN THE PATHOGENESIS OF CHRONIC INFLAMMATORY DISEASES BY REGULATING DIFFERENTIATION, PROLIFERATION, APOPTOSIS, AND ACTIVATION OF IMMUNE CELLS. CHANGES IN THE METHYLATION STATUS OF RELEVANT GENES HAVE BEEN LINKED TO THE ORIGIN, PERPETUATION, AND SEVERITY OF AIRWAY DISEASES. THE DNA METHYLATION PROFILE CAN BE ALSO MODIFIED BY THE ACTION OF VIRAL AND BACTERIAL COLONIZATION. BACTERIA AND SPECIALLY STAPHYLOCOCCUS AUREUS TOXINS ARE RECOGNIZED INFLAMMATORY AMPLIFYING FACTORS IN BOTH LOWER AND UPPER AIRWAY CHRONIC DISEASES. THIS REVIEW SUMMARIZES THE EXISTENT KNOWLEDGE ABOUT THE ROLE OF DNA METHYLATION CHANGES IN CHRONIC AIRWAY DISEASES AND THE CONTRIBUTION OF BACTERIAL INFECTION ON THIS EVENT. RECENT FINDINGS: IT HAS BEEN DEMONSTRATED THAT CHANGES IN DNA METHYLATION, EITHER INTRINSIC OR INDUCED BY ALLERGEN OR INFECTION, MAY BE LINKED TO THE PATHOGENESIS OF ASTHMA AND ALLERGY. THESE CHANGES IN METHYLATION MAY SUPPRESS THE PRODUCTION OF ANTI-INFLAMMATORY MEDIATORS AND INCREASE THE SURVIVAL AND ACTIVATION OF PRO-INFLAMMATORY CELLS, AS WELL AS MODIFY THE IMMUNE RESPONSE IN RESPONSE TO BACTERIAL INFECTION, INCREASING THEIR SURVIVAL AND PATHOGENICITY WITHIN THE INFECTED ORGANISM. SUMMARY: UNDERSTANDING THE INTRINSIC EPIGENETIC MECHANISMS, AS WELL AS THE EFFECT OF ENVIRONMENT -FOR EXAMPLE, BACTERIAL INFECTION IN THE PATHOGENESIS OF AIRWAYS DISEASES - WILL GREATLY IMPROVE THE MANAGEMENT AND THE DIAGNOSIS OF THESE DISEASES. 2015 15 2600 28 EPIGENETICS REGULATION DURING VIRUS-HOST INTERACTION AND THEIR EFFECTS ON THE VIRUS AND HOST CELL. EPIGENETICS, A FIELD OF STUDY FOCUSED ON CELLULAR GENE REGULATION INDEPENDENT OF DNA SEQUENCE ALTERATIONS, ENCOMPASSES DNA METHYLATION, HISTONE MODIFICATION AND MICRORNA MODIFICATION. EPIGENETICS PROCESSES PLAY A PIVOTAL ROLE IN GOVERNING THE LIFE CYCLES OF VIRUSES, ENABLING THEIR TRANSMISSION, PERSISTENCE, AND MAINTENANCE WITH IN HOST ORGANISMS. THIS REVIEW EXAMINES THE EPIGENETICS REGULATION OF DIVERSE VIRUS INCLUDING ORTHOMOXYVIRUSES, CORONAVIRUS, RETROVIRIDAE, MONONEGAVIRALES, AND POXVIRUSES AMONG OTHERS. THE INVESTIGATION ENCOMPASSES TEN REPRESENTATIVE VIRUSES FROM THESE FAMILIES. DETAILED EXPLORATION OF THE EPIGENETIC MECHANISMS UNDERLYING EACH VIRUS TYPE, INVOLVING MIRNA MODIFICATION, HISTONE MODIFICATION AND DNA METHYLATION, SHEDS LIGHT ON THE INTRICATE AND MULTIFACETED EPIGENETIC INTERPLAY BETWEEN VIRUSES AND THEIR HOSTS. FURTHERMORE, THIS REVIEW INVESTIGATES THE INFLUENCE OF THESE EPIGENETIC PROCESSES ON INFECTION CYCLES, EMPHASIZING THE UTILIZATION OF EPIGENETICS BY VIRUSES SUCH AS EPSTEIN-BARR VIRUS AND HUMAN IMMUNODEFICIENCY VIRUS (HIV) TO REGULATE GENE EXPRESSION DURING CHRONIC OR LATENT INFECTIONS, CONTROL LATENCY, AND TRANSITION TO LYTIC INFECTION. FINALLY, THE PAPER EXPLORES THE NOVEL TREATMENTS POSSIBILITIES STEMMING FROM THIS EPIGENETIC UNDERSTANDING. 2023 16 1912 31 ENVIRONMENT, DIET AND CPG ISLAND METHYLATION: EPIGENETIC SIGNALS IN GASTROINTESTINAL NEOPLASIA. THE EPITHELIAL SURFACES OF THE MAMMALIAN ALIMENTARY TRACT ARE CHARACTERISED BY VERY HIGH RATES OF CELL PROLIFERATION AND DNA SYNTHESIS, AND IN HUMANS THEY ARE HIGHLY SUSCEPTIBLE TO CANCER. THE ROLE OF SOMATIC MUTATIONS AS DRIVERS OF CARCINOGENESIS IN THE ALIMENTARY TRACT IS WELL ESTABLISHED, BUT THE IMPORTANCE OF GENE SILENCING BY EPIGENETIC MECHANISMS IS INCREASINGLY RECOGNISED. METHYLATION OF CPG ISLANDS IS AN IMPORTANT COMPONENT OF THE EPIGENETIC CODE THAT REGULATES GENE EXPRESSION DURING DEVELOPMENT AND NORMAL CELLULAR DIFFERENTIATION, AND A NUMBER OF GENES ARE WELL KNOWN TO BECOME ABNORMALLY METHYLATED DURING THE DEVELOPMENT OF TUMOURS OF THE OESOPHAGUS, STOMACH AND COLORECTUM. ABERRANT PATTERNS OF DNA METHYLATION DEVELOP AS A RESULT OF PATHOLOGICAL PROCESSES SUCH AS CHRONIC INFLAMMATION, AND IN RESPONSE TO VARIOUS DIETARY FACTORS, INCLUDING IMBALANCES IN THE SUPPLY OF METHYL DONORS, PARTICULARLY FOLATES, AND EXPOSURE TO DNA METHYLTRANSFERASE INHIBITORS, WHICH INCLUDE POLYPHENOLS AND POSSIBLY ISOTHIOCYANATES FROM PLANT FOODS. HOWEVER THE IMPORTANCE OF THESE ENVIRONMENTAL INTERACTIONS IN HUMAN HEALTH AND DISEASE REMAINS TO BE ESTABLISHED. RECENT MOVES TO MODIFY THE EXPOSURE OF HUMAN POPULATIONS TO FOLATE, BY MANDATORY SUPPLEMENTATION OF CEREAL FOODS, EMPHASISE THE IMPORTANCE OF UNDERSTANDING THE SUSCEPTIBILITY OF THE HUMAN EPIGENOME TO DIETARY AND OTHER ENVIRONMENTAL EFFECTS. 2008 17 2059 28 EPIGENETIC CONTROL OF GENE EXPRESSION IN THE LUNG. EPIGENETICS IS TRADITIONALLY DEFINED AS THE STUDY OF HERITABLE CHANGES IN GENE EXPRESSION CAUSED BY MECHANISMS OTHER THAN CHANGES IN THE UNDERLYING DNA SEQUENCE. THERE ARE THREE MAIN CLASSES OF EPIGENETIC MARKS--DNA METHYLATION, MODIFICATIONS OF HISTONE TAILS, AND NONCODING RNAS--EACH OF WHICH MAY BE INFLUENCED BY THE ENVIRONMENT, DIET, DISEASES, AND AGEING. IMPORTANTLY, EPIGENETIC MARKS HAVE BEEN SHOWN TO INFLUENCE IMMUNE CELL MATURATION AND ARE ASSOCIATED WITH THE RISK OF DEVELOPING VARIOUS FORMS OF CANCER, INCLUDING LUNG CANCER. MOREOVER, THERE IS EMERGING EVIDENCE THAT THESE EPIGENETIC MARKS AFFECT GENE EXPRESSION IN THE LUNG AND ARE ASSOCIATED WITH BENIGN LUNG DISEASES, SUCH AS ASTHMA, CHRONIC OBSTRUCTIVE PULMONARY DISEASE, AND INTERSTITIAL LUNG DISEASE. TECHNOLOGICAL ADVANCES HAVE MADE IT FEASIBLE TO STUDY EPIGENETIC MARKS IN THE LUNG, AND IT IS ANTICIPATED THAT THIS KNOWLEDGE WILL ENHANCE OUR UNDERSTANDING OF THE DYNAMIC BIOLOGY IN THE LUNG AND LEAD TO THE DEVELOPMENT OF NOVEL DIAGNOSTIC AND THERAPEUTIC APPROACHES FOR OUR PATIENTS WITH LUNG DISEASE. 2011 18 376 23 AN EPI(C)GENETIC WAR: PATHOGENS, CANCER AND HUMAN GENOME. CANCER IS CHARACTERIZED BY INTER- AND INTRA-TUMOR HETEROGENEITY AND THIS IS ALSO OBSERVED IN THE CONTEXT OF CANCERS CAUSED BY PATHOGENS. NEARLY 20% OF ALL CANCERS ARE ATTRIBUTABLE TO PATHOGENIC ORGANISMS. PATHOGENIC INFECTIONS RESULT IN DEREGULATION OF GENE EXPRESSION BOTH BY GENETIC AND EPIGENETIC MECHANISMS, THEREBY CAUSING MALIGNANT TRANSFORMATION. ANOTHER CHARACTERISTIC OF PATHOGEN-INDUCED CANCERS IS THE OCCURRENCE OF CHRONIC INFLAMMATION DUE TO ACTIVATION OF THE INNATE AND ADAPTIVE ARMS OF THE IMMUNE SYSTEM. THIS REVIEW FOCUSES ON THE EPIGENETIC CHANGES INDUCED BY ONCOVIRUSES, PARASITES, CANCER-CAUSING BACTERIA AND 'ENDOGENOUS PATHOGENS' TO TRIGGER HOST CELL PROLIFERATION INDEFINITELY AS WELL AS THE INFLAMMATION ASSOCIATED WITH PATHOGEN-INDUCED CANCERS. THE OPPORTUNITY OF TARGETING COMPONENTS OF BOTH PATHOGEN AND HOST EPIGENETIC MACHINERY TO LIMIT TUMOR PROGRESSION IS ALSO DISCUSSED. 2018 19 6340 33 THE ROLE OF EPIGENETIC FACTORS IN PSORIASIS. PSORIASIS IS A CHRONIC, SYSTEMIC, IMMUNE-MEDIATED DISEASE WITH AN INCIDENCE OF APPROXIMATELY 2%. THE PATHOGENESIS OF THE DISEASE IS COMPLEX AND NOT YET FULLY UNDERSTOOD. GENETIC FACTORS PLAY A SIGNIFICANT ROLE IN THE PATHOGENESIS OF THE DISEASE. IN PREDISPOSED INDIVIDUALS, MULTIPLE TRIGGER FACTORS MAY CONTRIBUTE TO DISEASE ONSET AND EXACERBATIONS OF SYMPTOMS. ENVIRONMENTAL FACTORS (STRESS, INFECTIONS, CERTAIN MEDICATIONS, NICOTINISM, ALCOHOL, OBESITY) PLAY A SIGNIFICANT ROLE IN THE PATHOGENESIS OF PSORIASIS. IN ADDITION, EPIGENETIC MECHANISMS ARE CONSIDERED RESULT IN MODULATION OF INDIVIDUAL GENE EXPRESSION AND AN INCREASED LIKELIHOOD OF THE DISEASE. STUDIES HIGHLIGHT THE SIGNIFICANT ROLE OF EPIGENETIC FACTORS IN THE ETIOLOGY AND PATHOGENESIS OF PSORIASIS. EPIGENETIC MECHANISMS IN PSORIASIS INCLUDE DNA METHYLATION, HISTONE MODIFICATIONS AND NON-CODING RNAS. EPIGENETIC MECHANISMS INDUCE GENE EXPRESSION CHANGES UNDER THE INFLUENCE OF CHEMICAL MODIFICATIONS OF DNA AND HISTONES, WHICH ALTER CHROMATIN STRUCTURE AND ACTIVATE TRANSCRIPTION FACTORS OF SELECTED GENES, THUS LEADING TO TRANSLATION OF NEW MRNA WITHOUT AFFECTING THE DNA SEQUENCE. EPIGENETIC FACTORS CAN REGULATE GENE EXPRESSION AT THE TRANSCRIPTIONAL (VIA HISTONE MODIFICATION, DNA METHYLATION) AND POSTTRANSCRIPTIONAL LEVELS (VIA MICRORNAS AND LONG NON-CODING RNAS). THIS STUDY AIMS TO PRESENT AND DISCUSS THE DIFFERENT EPIGENETIC MECHANISMS IN PSORIASIS BASED ON A REVIEW OF THE AVAILABLE LITERATURE. 2021 20 6100 38 THE EMERGING ROLE OF EPIGENETIC MODIFIERS IN REPAIR OF DNA DAMAGE ASSOCIATED WITH CHRONIC INFLAMMATORY DISEASES. AT SITES OF CHRONIC INFLAMMATION EPITHELIAL CELLS ARE EXPOSED TO HIGH LEVELS OF REACTIVE OXYGEN SPECIES (ROS), WHICH CAN CONTRIBUTE TO THE INITIATION AND DEVELOPMENT OF MANY DIFFERENT HUMAN CANCERS. ABERRANT EPIGENETIC ALTERATIONS THAT CAUSE TRANSCRIPTIONAL SILENCING OF TUMOR SUPPRESSOR GENES ARE ALSO IMPLICATED IN MANY DISEASES ASSOCIATED WITH INFLAMMATION, INCLUDING CANCER. HOWEVER, IT IS NOT CLEAR HOW ALTERED EPIGENETIC GENE SILENCING IS INITIATED DURING CHRONIC INFLAMMATION. THE HIGH LEVEL OF ROS AT SITES OF INFLAMMATION IS KNOWN TO INDUCE OXIDATIVE DNA DAMAGE IN SURROUNDING EPITHELIAL CELLS. FURTHERMORE, DNA DAMAGE IS KNOWN TO TRIGGER SEVERAL RESPONSES, INCLUDING RECRUITMENT OF DNA REPAIR PROTEINS, TRANSCRIPTIONAL REPRESSION, CHROMATIN MODIFICATIONS AND OTHER CELL SIGNALING EVENTS. RECRUITMENT OF EPIGENETIC MODIFIERS TO CHROMATIN IN RESPONSE TO DNA DAMAGE RESULTS IN TRANSIENT COVALENT MODIFICATIONS TO CHROMATIN SUCH AS HISTONE UBIQUITINATION, ACETYLATION AND METHYLATION AND DNA METHYLATION. DNA DAMAGE ALSO ALTERS NON-CODING RNA EXPRESSION. ALL OF THESE ALTERATIONS HAVE THE POTENTIAL TO ALTER GENE EXPRESSION AT SITES OF DAMAGE. TYPICALLY, THESE MODIFICATIONS AND GENE TRANSCRIPTION ARE RESTORED BACK TO NORMAL ONCE THE REPAIR OF THE DNA DAMAGE IS COMPLETED. HOWEVER, CHRONIC INFLAMMATION MAY INDUCE SUSTAINED DNA DAMAGE AND DNA DAMAGE RESPONSES THAT RESULT IN THESE TRANSIENT COVALENT CHROMATIN MODIFICATIONS BECOMING MITOTICALLY STABLE EPIGENETIC ALTERATIONS. UNDERSTANDING HOW EPIGENETIC ALTERATIONS ARE INITIATED DURING CHRONIC INFLAMMATION WILL ALLOW US TO DEVELOP PHARMACEUTICAL STRATEGIES TO PREVENT OR TREAT CHRONIC INFLAMMATION-INDUCED CANCER. THIS REVIEW WILL FOCUS ON TYPES OF DNA DAMAGE AND EPIGENETIC ALTERATIONS ASSOCIATED WITH CHRONIC INFLAMMATORY DISEASES, THE TYPES OF DNA DAMAGE AND TRANSIENT COVALENT CHROMATIN MODIFICATIONS INDUCED BY INFLAMMATION AND OXIDATIVE DNA DAMAGE AND HOW THESE MODIFICATIONS MAY RESULT IN EPIGENETIC ALTERATIONS. 2019