1 6622 144 UNDERSTANDING HAT1: A COMPREHENSIVE REVIEW OF NONCANONICAL ROLES AND CONNECTION WITH DISEASE. HISTONE ACETYLATION PLAYS A VITAL ROLE IN ORGANIZING CHROMATIN, REGULATING GENE EXPRESSION AND CONTROLLING THE CELL CYCLE. THE FIRST HISTONE ACETYLTRANSFERASE TO BE IDENTIFIED WAS HISTONE ACETYLTRANSFERASE 1 (HAT1), BUT IT REMAINS ONE OF THE LEAST UNDERSTOOD ACETYLTRANSFERASES. HAT1 CATALYZES THE ACETYLATION OF NEWLY SYNTHESIZED H4 AND, TO A LESSER EXTENT, H2A IN THE CYTOPLASM. HOWEVER, 20 MIN AFTER ASSEMBLY, HISTONES LOSE ACETYLATION MARKS. MOREOVER, NEW NONCANONICAL FUNCTIONS HAVE BEEN DESCRIBED FOR HAT1, REVEALING ITS COMPLEXITY AND COMPLICATING THE UNDERSTANDING OF ITS FUNCTIONS. RECENTLY DISCOVERED ROLES INCLUDE FACILITATING THE TRANSLOCATION OF THE H3H4 DIMER INTO THE NUCLEUS, INCREASING THE STABILITY OF THE DNA REPLICATION FORK, REPLICATION-COUPLED CHROMATIN ASSEMBLY, COORDINATION OF HISTONE PRODUCTION, DNA DAMAGE REPAIR, TELOMERIC SILENCING, EPIGENETIC REGULATION OF NUCLEAR LAMINA-ASSOCIATED HETEROCHROMATIN, REGULATION OF THE NF-KAPPAB RESPONSE, SUCCINYL TRANSFERASE ACTIVITY AND MITOCHONDRIAL PROTEIN ACETYLATION. IN ADDITION, THE FUNCTIONS AND EXPRESSION LEVELS OF HAT1 HAVE BEEN LINKED TO MANY DISEASES, SUCH AS MANY TYPES OF CANCER, VIRAL INFECTIONS (HEPATITIS B VIRUS, HUMAN IMMUNODEFICIENCY VIRUS AND VIPERIN SYNTHESIS) AND INFLAMMATORY DISEASES (CHRONIC OBSTRUCTIVE PULMONARY DISEASE, ATHEROSCLEROSIS AND ISCHEMIC STROKE). THE COLLECTIVE DATA REVEAL THAT HAT1 IS A PROMISING THERAPEUTIC TARGET, AND NOVEL THERAPEUTIC APPROACHES, SUCH AS RNA INTERFERENCE AND THE USE OF APTAMERS, BISUBSTRATE INHIBITORS AND SMALL-MOLECULE INHIBITORS, ARE BEING EVALUATED AT THE PRECLINICAL LEVEL. 2023 2 1326 25 DEPLETION OF NUCLEAR HISTONE H2A VARIANTS IS ASSOCIATED WITH CHRONIC DNA DAMAGE SIGNALING UPON DRUG-EVOKED SENESCENCE OF HUMAN SOMATIC CELLS. CELLULAR SENESCENCE IS ASSOCIATED WITH GLOBAL CHROMATIN CHANGES, ALTERED GENE EXPRESSION, AND ACTIVATION OF CHRONIC DNA DAMAGE SIGNALING. THESE EVENTS ULTIMATELY LEAD TO MORPHOLOGICAL AND PHYSIOLOGICAL TRANSFORMATIONS IN PRIMARY CELLS. IN THIS STUDY, WE SHOW THAT CHRONIC DNA DAMAGE SIGNALS CAUSED BY GENOTOXIC STRESS IMPACT THE EXPRESSION OF HISTONES H2A FAMILY MEMBERS AND LEAD TO THEIR DEPLETION IN THE NUCLEI OF SENESCENT HUMAN FIBROBLASTS. OUR DATA REINFORCE THE HYPOTHESIS THAT PROGRESSIVE CHROMATIN DESTABILIZATION MAY LEAD TO THE LOSS OF EPIGENETIC INFORMATION AND IMPAIRED CELLULAR FUNCTION ASSOCIATED WITH CHRONIC DNA DAMAGE UPON DRUG-EVOKED SENESCENCE. WE PROPOSE THAT CHANGES IN THE HISTONE BIOSYNTHESIS AND CHROMATIN ASSEMBLY MAY DIRECTLY CONTRIBUTE TO CELLULAR AGING. IN ADDITION, WE ALSO OUTLINE THE METHOD THAT ALLOWS FOR QUANTITATIVE AND UNBIASED MEASUREMENT OF THESE CHANGES. 2012 3 2055 30 EPIGENETIC CONTROL DURING LYMPHOID DEVELOPMENT AND IMMUNE RESPONSES: ABERRANT REGULATION, VIRUSES, AND CANCER. METHYLATION OF CYTOSINES CONTROLS A NUMBER OF BIOLOGIC PROCESSES SUCH AS IMPRINTING AND X CHROMOSOMAL INACTIVATION. DNA HYPERMETHYLATION IS CLOSELY ASSOCIATED WITH TRANSCRIPTIONAL SILENCING, WHILE DNA HYPOMETHYLATION IS ASSOCIATED WITH TRANSCRIPTIONAL ACTIVATION. HYPOACETYLATION OF HISTONES LEADS TO COMPACT CHROMATIN WITH REDUCED ACCESSIBILITY TO THE TRANSCRIPTIONAL MACHINERY. METHYL-CPG BINDING PROTEINS CAN RECRUIT COREPRESSORS AND HISTONE DEACETYLASES; THUS, THE INTERPLAY BETWEEN THESE EPIGENETIC MECHANISMS REGULATES GENE ACTIVATION. METHYLATION HAS BEEN IMPLICATED AS AN IMPORTANT MECHANISM DURING IMMUNE DEVELOPMENT, CONTROLLING VDJ RECOMBINATION, LINEAGE-SPECIFIC EXPRESSION OF CELL SURFACE ANTIGENS, AND TRANSCRIPTIONAL REGULATION OF CYTOKINE GENES DURING IMMUNE RESPONSES. ABERRATIONS IN EPIGENETIC MACHINERY, EITHER BY GENETIC MUTATIONS OR BY SOMATIC CHANGES SUCH AS VIRAL INFECTIONS, ARE ASSOCIATED WITH EARLY ALTERATIONS IN CHRONIC DISEASES SUCH AS IMMUNODEFICIENCY AND CANCER. 2003 4 2493 44 EPIGENETICS AND CHROMATIN REMODELING PLAY A ROLE IN LUNG DISEASE. EPIGENETICS IS DEFINED AS HERITABLE CHANGES THAT AFFECT GENE EXPRESSION WITHOUT ALTERING THE DNA SEQUENCE. EPIGENETIC REGULATION OF GENE EXPRESSION IS FACILITATED THROUGH DIFFERENT MECHANISMS SUCH AS DNA METHYLATION, HISTONE MODIFICATIONS AND RNA-ASSOCIATED SILENCING BY SMALL NON-CODING RNAS. ALL THESE MECHANISMS ARE CRUCIAL FOR NORMAL DEVELOPMENT, DIFFERENTIATION AND TISSUE-SPECIFIC GENE EXPRESSION. THESE THREE SYSTEMS INTERACT AND STABILIZE ONE ANOTHER AND CAN INITIATE AND SUSTAIN EPIGENETIC SILENCING, THUS DETERMINING HERITABLE CHANGES IN GENE EXPRESSION. HISTONE ACETYLATION REGULATES DIVERSE CELLULAR FUNCTIONS INCLUDING INFLAMMATORY GENE EXPRESSION, DNA REPAIR AND CELL PROLIFERATION. TRANSCRIPTIONAL COACTIVATORS POSSESS INTRINSIC HISTONE ACETYLTRANSFERASE ACTIVITY AND THIS ACTIVITY DRIVES INFLAMMATORY GENE EXPRESSION. ELEVEN CLASSICAL HISTONE DEACETYLASES (HDACS) ACT TO REGULATE THE EXPRESSION OF DISTINCT SUBSETS OF INFLAMMATORY/IMMUNE GENES. THUS, LOSS OF HDAC ACTIVITY OR THE PRESENCE OF HDAC INHIBITORS CAN FURTHER ENHANCE INFLAMMATORY GENE EXPRESSION BY PRODUCING A GENE-SPECIFIC CHANGE IN HAT ACTIVITY. FOR EXAMPLE, HDAC2 EXPRESSION AND ACTIVITY ARE REDUCED IN LUNG MACROPHAGES, BIOPSY SPECIMENS, AND BLOOD CELLS FROM PATIENTS WITH SEVERE ASTHMA AND SMOKING ASTHMATICS, AS WELL AS IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). THIS MAY ACCOUNT, AT LEAST IN PART, FOR THE ENHANCED INFLAMMATION AND REDUCED STEROID RESPONSIVENESS SEEN IN THESE PATIENTS. OTHER PROTEINS, PARTICULARLY TRANSCRIPTION FACTORS, ARE ALSO ACETYLATED AND ARE TARGETS FOR DEACETYLATION BY HDACS AND SIRTUINS, A RELATED FAMILY OF 7 PREDOMINANTLY PROTEIN DEACETYLASES. THUS THE ACETYLATION/DEACETYLATION STATUS OF NF-KAPPAB AND THE GLUCOCORTICOID RECEPTOR CAN ALSO AFFECT THE OVERALL EXPRESSION PATTERN OF INFLAMMATORY GENES AND REGULATE THE INFLAMMATORY RESPONSE. UNDERSTANDING AND TARGETING SPECIFIC ENZYMES INVOLVED IN THIS PROCESS MIGHT LEAD TO NEW THERAPEUTIC AGENTS, PARTICULARLY IN SITUATIONS IN WHICH CURRENT ANTI-INFLAMMATORY THERAPIES ARE SUBOPTIMAL. 2011 5 834 30 CHEMICAL BIOLOGY OF LYSINE DEMETHYLASES. ABNORMAL LEVELS OF DNA METHYLATION AND/OR HISTONE MODIFICATIONS ARE OBSERVED IN PATIENTS WITH A WIDE VARIETY OF CHRONIC DISEASES. METHYLATION OF LYSINES WITHIN HISTONE TAILS IS A KEY MODIFICATION THAT CONTRIBUTES TO INCREASED GENE EXPRESSION OR REPRESSION DEPENDING ON THE SPECIFIC RESIDUE AND DEGREE OF METHYLATION, WHICH IS IN TURN CONTROLLED BY THE INTERPLAY OF LYSINE METHYL TRANSFERASES AND DEMETHYLASES. DRUGS THAT TARGET THESE AND OTHER ENZYMES CONTROLLING CHROMATIN MODIFICATIONS CAN MODULATE THE EXPRESSION OF CLUSTERS OF GENES, POTENTIALLY OFFERING HIGHER THERAPEUTIC EFFICACY THAN CLASSICAL AGENTS ACTING ON DOWNSTREAM BIOCHEMICAL PATHWAYS THAT ARE SUSCEPTIBLE TO DEGENERACY. LYSINE DEMETHYLASES, FIRST DISCOVERED IN 2004, ARE THE SUBJECT OF INCREASING INTEREST AS THERAPEUTIC TARGETS. THIS REVIEW PROVIDES AN OVERVIEW OF RECENT FINDINGS IMPLICATING LYSINE DEMETHYLASES IN A RANGE OF THERAPEUTIC AREAS INCLUDING ONCOLOGY, IMMUNOINFLAMMATION, METABOLIC DISORDERS, NEUROSCIENCE, VIROLOGY AND REGENERATIVE MEDICINE, TOGETHER WITH A SUMMARY OF RECENT ADVANCES IN STRUCTURAL BIOLOGY AND SMALL MOLECULE INHIBITOR DISCOVERY, SUPPORTING THE TRACTABILITY OF THE PROTEIN FAMILY FOR THE DEVELOPMENT OF SELECTIVE DRUGLIKE INHIBITORS. 2011 6 6100 41 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 7 5937 35 TARGETING HISTONE DEACETYLASE ACTIVITY IN RHEUMATOID ARTHRITIS AND ASTHMA AS PROTOTYPES OF INFLAMMATORY DISEASE: SHOULD WE KEEP OUR HATS ON? CELLULAR ACTIVATION, PROLIFERATION AND SURVIVAL IN CHRONIC INFLAMMATORY DISEASES IS REGULATED NOT ONLY BY ENGAGEMENT OF SIGNAL TRANS-DUCTION PATHWAYS THAT MODULATE TRANSCRIPTION FACTORS REQUIRED FOR THESE PROCESSES, BUT ALSO BY EPIGENETIC REGULATION OF TRANSCRIPTION FACTOR ACCESS TO GENE PROMOTER REGIONS. HISTONE ACETYL TRANSFERASES COORDINATE THE RECRUITMENT AND ACTIVATION OF TRANSCRIPTION FACTORS WITH CONFORMATIONAL CHANGES IN HISTONES THAT ALLOW GENE PROMOTER EXPOSURE. HISTONE DEACETYLASES (HDACS) COUNTERACT HISTONE ACETYL TRANSFERASE ACTIVITY THROUGH THE TARGETING OF BOTH HISTONES AS WELL AS NONHISTONE SIGNAL TRANSDUCTION PROTEINS IMPORTANT IN INFLAMMATION. NUMEROUS STUDIES HAVE INDICATED THAT DEPRESSED HDAC ACTIVITY IN PATIENTS WITH INFLAMMATORY AIRWAY DISEASES MAY CONTRIBUTE TO LOCAL PROINFLAMMATORY CYTOKINE PRODUCTION AND DIMINISH PATIENT RESPONSES TO CORTICOSTEROID TREATMENT. RECENT OBSERVATIONS THAT HDAC ACTIVITY IS DEPRESSED IN RHEUMATOID ARTHRITIS PATIENT SYNOVIAL TISSUE HAVE PREDICTED THAT STRATEGIES RESTORING HDAC FUNCTION MAY BE THERAPEUTIC IN THIS DISEASE AS WELL. PHARMACOLOGICAL INHIBITORS OF HDAC ACTIVITY, HOWEVER, HAVE DEMONSTRATED POTENT THERAPEUTIC EFFECTS IN ANIMAL MODELS OF ARTHRITIS AND OTHER CHRONIC INFLAMMATORY DISEASES. IN THE PRESENT REVIEW WE ASSESS AND RECONCILE THESE OUTWARDLY PARADOXICAL STUDY RESULTS TO PROVIDE A WORKING MODEL FOR HOW ALTERATIONS IN HDAC ACTIVITY MAY CONTRIBUTE TO PATHOLOGY IN RHEUMATOID ARTHRITIS, AND HIGHLIGHT KEY QUESTIONS TO BE ANSWERED IN THE PRECLINICAL EVALUATION OF COMPOUNDS MODULATING THESE ENZYMES. 2008 8 1251 32 CURRENT PERSPECTIVES ON ROLE OF CHROMATIN MODIFICATIONS AND DEACETYLASES IN LUNG INFLAMMATION IN COPD. CHROMATIN MODIFICATIONS AND EPIGENETIC REGULATION ARE CRITICAL FOR SUSTAINED AND ABNORMAL INFLAMMATORY RESPONSE SEEN IN LUNGS OF PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) BECAUSE THE ACTIVITIES OF ENZYMES THAT REGULATE THESE EPIGENETIC MODIFICATIONS ARE ALTERED IN RESPONSE TO CIGARETTE SMOKE. CIGARETTE SMOKE INDUCES CHROMATIN MODIFICATIONS AND EPIGENETIC CHANGES BY CAUSING POST-TRANSLATIONAL MODIFICATIONS OF HISTONE ACETYLTRANSFERASES, AND HISTONE/NON-HISTONE DEACETYLASES (HDACS), SUCH AS HDAC2 AND SIRTUIN 1 (SIRT1), WHICH LEADS TO CHROMATIN REMODELING. IN THIS REVIEW, WE DISCUSSED THE CURRENT KNOWLEDGE ON CIGARETTE SMOKE/OXIDANTS-INDUCED POST-TRANSLATIONAL MODIFICATIONS OF DEACETYLASES (HDAC2 AND SIRT1), DISRUPTION OF HDAC2/SIRT1-RELA/P65 COREPRESSOR COMPLEX ASSOCIATED WITH ACETYLATION OF RELA/P65, AND CHROMATIN MODIFICATIONS (HISTONE H3 PHOSPHO-ACETYLATION) LEADING TO SUSTAINED PRO-INFLAMMATORY GENE TRANSCRIPTION. KNOWLEDGE ON MOLECULAR MECHANISMS OF EPIGENETIC CHANGES IN ABNORMAL LUNG INFLAMMATION WILL HELP IN UNDERSTANDING THE PATHOPHYSIOLOGY OF COPD WHICH MAY LEAD TO THE DEVELOPMENT OF NOVEL EPIGENETIC THERAPIES IN THE NEAR FUTURE. 2009 9 3207 36 HDACI: CELLULAR EFFECTS, OPPORTUNITIES FOR RESTORATIVE DENTISTRY. ACETYLATION OF HISTONE AND NON-HISTONE PROTEINS ALTERS GENE EXPRESSION AND INDUCES A HOST OF CELLULAR EFFECTS. THE ACETYLATION PROCESS IS HOMEOSTATICALLY BALANCED BY TWO GROUPS OF CELLULAR ENZYMES, HISTONE ACETYLTRANSFERASES (HATS) AND HISTONE DEACETYLASES (HDACS). HAT ACTIVITY RELAXES THE STRUCTURE OF THE HUMAN CHROMATIN, RENDERING IT TRANSCRIPTIONALLY ACTIVE, THEREBY INCREASING GENE EXPRESSION. IN CONTRAST, HDAC ACTIVITY LEADS TO GENE SILENCING. THE ENZYMATIC BALANCE CAN BE 'TIPPED' BY HISTONE DEACETYLASE INHIBITORS (HDACI), LEADING TO AN ACCUMULATION OF ACETYLATED PROTEINS, WHICH SUBSEQUENTLY MODIFY CELLULAR PROCESSES INCLUDING STEM CELL DIFFERENTIATION, CELL CYCLE, APOPTOSIS, GENE EXPRESSION, AND ANGIOGENESIS. THERE IS A VARIETY OF NATURAL AND SYNTHETIC HDACI AVAILABLE, AND THEIR PLEIOTROPIC EFFECTS HAVE CONTRIBUTED TO DIVERSE CLINICAL APPLICATIONS, NOT ONLY IN CANCER BUT ALSO IN NON-CANCER AREAS, SUCH AS CHRONIC INFLAMMATORY DISEASE, BONE ENGINEERING, AND NEURODEGENERATIVE DISEASE. INDEED, IT APPEARS THAT HDACI-MODULATED EFFECTS MAY DIFFER BETWEEN 'NORMAL' AND TRANSFORMED CELLS, PARTICULARLY WITH REGARD TO REACTIVE OXYGEN SPECIES ACCUMULATION, APOPTOSIS, PROLIFERATION, AND CELL CYCLE ARREST. THE POTENTIAL BENEFICIAL EFFECTS OF HDACI FOR HEALTH, RESULTING FROM THEIR ABILITY TO REGULATE GLOBAL GENE EXPRESSION BY EPIGENETIC MODIFICATION OF DNA-ASSOCIATED PROTEINS, ALSO OFFER POTENTIAL FOR APPLICATION WITHIN RESTORATIVE DENTISTRY, WHERE THEY MAY PROMOTE DENTAL TISSUE REGENERATION FOLLOWING PULPAL DAMAGE. 2011 10 3322 33 HISTONE ACETYLTRANSFERASE P300 INDUCES DE NOVO SUPER-ENHANCERS TO DRIVE CELLULAR SENESCENCE. ACCUMULATION OF SENESCENT CELLS DURING AGING CONTRIBUTES TO CHRONIC INFLAMMATION AND AGE-RELATED DISEASES. WHILE SENESCENCE IS ASSOCIATED WITH PROFOUND ALTERATIONS OF THE EPIGENOME, A SYSTEMATIC VIEW OF EPIGENETIC FACTORS IN REGULATING SENESCENCE IS LACKING. HERE, WE CURATED A LIBRARY OF SHORT HAIRPIN RNAS FOR TARGETED SILENCING OF ALL KNOWN EPIGENETIC PROTEINS AND PERFORMED A HIGH-THROUGHPUT SCREEN TO IDENTIFY KEY CANDIDATES WHOSE DOWNREGULATION CAN DELAY REPLICATIVE SENESCENCE OF PRIMARY HUMAN CELLS. THIS SCREEN IDENTIFIED MULTIPLE NEW PLAYERS INCLUDING THE HISTONE ACETYLTRANSFERASE P300 THAT WAS FOUND TO BE A PRIMARY DRIVER OF THE SENESCENT PHENOTYPE. P300, BUT NOT THE PARALOGOUS CBP, INDUCES A DYNAMIC HYPER-ACETYLATED CHROMATIN STATE AND PROMOTES THE FORMATION OF ACTIVE ENHANCER ELEMENTS IN THE NON-CODING GENOME, LEADING TO A SENESCENCE-SPECIFIC GENE EXPRESSION PROGRAM. OUR WORK ILLUSTRATES A CAUSAL ROLE OF HISTONE ACETYLTRANSFERASES AND ACETYLATION IN SENESCENCE AND SUGGESTS P300 AS A POTENTIAL THERAPEUTIC TARGET FOR SENESCENCE AND AGE-RELATED DISEASES. 2019 11 5550 35 ROLE OF EPIGENETICS IN INFLAMMATION-ASSOCIATED DISEASES. THERE IS CONSIDERABLE EVIDENCE SUGGESTING THAT EPIGENETIC MECHANISMS MAY MEDIATE DEVELOPMENT OF CHRONIC INFLAMMATION BY MODULATING THE EXPRESSION OF PRO-INFLAMMATORY CYTOKINE TNF-ALPHA, INTERLEUKINS, TUMOR SUPPRESSOR GENES, ONCOGENES AND AUTOCRINE AND PARACRINE ACTIVATION OF THE TRANSCRIPTION FACTOR NF-KAPPAB. THESE MOLECULES ARE CONSTITUTIVELY PRODUCED BY A VARIETY OF CELLS UNDER CHRONIC INFLAMMATORY CONDITIONS, WHICH IN TURN LEADS TO THE DEVELOPMENT OF MAJOR DISEASES SUCH AS AUTOIMMUNE DISORDERS, CHRONIC OBSTRUCTIVE PULMONARY DISEASES, NEURODEGENERATIVE DISEASES AND CANCER. DISTINCT OR GLOBAL CHANGES IN THE EPIGENETIC LANDSCAPE ARE HALLMARKS OF CHRONIC INFLAMMATION DRIVEN DISEASES. EPIGENETICS INCLUDE CHANGES TO DISTINCT MARKERS ON THE GENOME AND ASSOCIATED CELLULAR TRANSCRIPTIONAL MACHINERY THAT ARE COPIED DURING CELL DIVISION (MITOSIS AND MEIOSIS). THESE CHANGES APPEAR FOR A SHORT SPAN OF TIME AND THEY NECESSARILY DO NOT MAKE PERMANENT CHANGES TO THE PRIMARY DNA SEQUENCE ITSELF. HOWEVER, THE MOST FREQUENTLY OBSERVED EPIGENETIC CHANGES INCLUDE ABERRANT DNA METHYLATION, AND HISTONE ACETYLATION AND DEACETYLATION. IN THIS CHAPTER, WE FOCUS ON PRO-INFLAMMATORY MOLECULES THAT ARE REGULATED BY ENZYMES INVOLVED IN EPIGENETIC MODIFICATIONS SUCH AS ARGININE AND LYSINE METHYL TRANSFERASES, DNA METHYLTRANSFERASE, HISTONE ACETYLTRANSFERASES AND HISTONE DEACETYLASES AND THEIR ROLE IN INFLAMMATION DRIVEN DISEASES. AGENTS THAT MODULATE OR INHIBIT THESE EPIGENETIC MODIFICATIONS, SUCH AS HAT OR HDAC INHIBITORS HAVE SHOWN GREAT POTENTIAL IN INHIBITING THE PROGRESSION OF THESE DISEASES. GIVEN THE PLASTICITY OF THESE EPIGENETIC CHANGES AND THEIR READINESS TO RESPOND TO INTERVENTION BY SMALL MOLECULE INHIBITORS, THERE IS A TREMENDOUS POTENTIAL FOR THE DEVELOPMENT OF NOVEL THERAPEUTICS THAT WILL SERVE AS DIRECT OR ADJUVANT THERAPEUTIC COMPOUNDS IN THE TREATMENT OF THESE DISEASES. 2013 12 5562 25 ROLE OF HISTONE DEACETYLASES IN PANCREAS: IMPLICATIONS FOR PATHOGENESIS AND THERAPY. IN THE LAST YEARS, OUR KNOWLEDGE OF THE PATHOGENESIS IN ACUTE AND CHRONIC PANCREATITIS (AP/CP) AS WELL AS IN PANCREATIC CANCEROGENESIS HAS SIGNIFICANTLY DIVERSIFIED. NEVERTHELESS, THE MEDICINAL THERAPEUTIC OPTIONS ARE STILL LIMITED AND THERAPEUTIC SUCCESS AND PATIENT OUTCOME ARE POOR. EPIGENETIC DEREGULATION OF GENE EXPRESSION IS KNOWN TO CONTRIBUTE TO DEVELOPMENT AND PROGRESSION OF AP AND CP AS WELL AS OF PANCREATIC CANCER. THEREFORE, THE SELECTIVE INHIBITION OF ABERRANTLY ACTIVE EPIGENETIC REGULATORS CAN BE AN EFFECTIVE OPTION FOR FUTURE THERAPIES. HISTONE DEACETYLASES (HDACS) ARE ENZYMES THAT REMOVE AN ACETYL GROUP FROM HISTONE TAILS, THEREBY CAUSING CHROMATIN COMPACTION AND REPRESSION OF TRANSCRIPTION. IN THIS REVIEW WE PRESENT AN OVERVIEW OF THE CURRENTLY AVAILABLE LITERATURE ADDRESSING THE ROLE OF HDACS IN THE PANCREAS AND IN PANCREATIC DISEASES. IN PANCREATIC CANCEROGENESIS, HDACS PLAY A ROLE IN THE IMPORTANT PROCESS OF EPITHELIAL-MESENCHYMAL-TRANSITION, UBIQUITIN-PROTEASOME PATHWAY AND, HYPOXIA-INDUCIBLE-FACTOR-1-ANGIOGENESIS. FINALLY, WE FOCUS ON HDACS AS POTENTIAL THERAPEUTIC TARGETS BY SUMMARIZING CURRENTLY AVAILABLE HISTONE DEACETYLASE INHIBITORS. 2015 13 3193 45 HDAC INHIBITION REGULATES OXIDATIVE STRESS IN CD4(+)THELPER CELLS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND NON-SMALL CELL LUNG CANCER PATIENTS VIA MITOCHONDRIAL TRANSCRIPTION FACTOR A (MTTFA) MODULATING NF-KAPPAB/HIF1ALPHA AXIS. HISTONE DEACETYLASES (HDACS) PLAY A CRUCIAL ROLE IN THE EPIGENETIC REGULATION OF GENE EXPRESSION BY REMODELLING CHROMATIN. ISOENZYMES OF THE HDAC FAMILY EXHIBIT ABERRANT REGULATION IN A WIDE VARIETY OF CANCERS AS WELL AS SEVERAL INFLAMMATORY LUNG DISORDERS LIKE CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). INHIBITION OF HDACS IS A POTENTIAL THERAPEUTIC STRATEGY THAT COULD BE USED TO REVERSE EPIGENETIC MODIFICATION. TRICHOSTATIN A (TSA), A POWERFUL HISTONE DEACETYLASE (HDAC) INHIBITOR, HAS ANTI-CANCER EFFECTS IN NUMEROUS CANCER TYPES. HOWEVER, IT IS NOT YET APPARENT HOW HDAC INHIBITORS AFFECT HUMAN NON-SMALL CELL LUNG CANCER CELLS (NSCLC) AND COPD. THIS STUDY AIMS TO INVESTIGATE TSA'S ROLE IN RESTORING MITOCHONDRIAL DYSFUNCTION AND ITS EFFECT ON HYPOXIA AND INFLAMMATION IN CD4(+)T CELLS OBTAINED FROM PATIENTS WITH COPD AND LUNG CANCER. AS A RESULT OF TREATMENT WITH TSA, THERE IS A REDUCTION IN THE EXPRESSION OF INFLAMMATORY CYTOKINES AND A DECREASED ENRICHMENT OF TRANSCRIPTIONAL FACTORS ASSOCIATED WITH INFLAMMATION AT VEGFA GENE LOCI. WE HAVE SEEN A SUBSTANTIAL DECREASE IN THE EXPRESSION OF NF-KAPPAB AND HIF1ALPHA, WHICH ARE THE CRITICAL MEDIATORS OF INFLAMMATION AND HYPOXIA, RESPECTIVELY. FOLLOWING TSA TREATMENT, MTTFA EXPRESSION WAS INCREASED, FACILITATING PATIENTS WITH COPD AND NSCLC IN THE RECOVERY OF THEIR DYSFUNCTIONAL MITOCHONDRIA. FURTHERMORE, WE HAVE DISCOVERED THAT TSA TREATMENT IN PATIENTS WITH COPD AND NSCLC MAY LEAD TO IMMUNOPROTECTIVE NESS BY INDUCING TH1NESS. OUR FINDING GIVES A NEW INSIGHT INTO THE EXISTING BODY OF KNOWLEDGE REGARDING TSA-BASED THERAPEUTIC METHODS AND HIGHLIGHTS THE NECESSITY OF EPIGENETIC THERAPY FOR THESE DEVASTATING LUNG DISORDERS. 2023 14 6533 36 TRANSCRIPTIONAL REGULATION OF INFLAMMATORY GENES ASSOCIATED WITH SEVERE ASTHMA. THE 10% OF PATIENTS WITH THE MOST SEVERE ASTHMA ARE RESPONSIBLE FOR A LARGE PART OF HEALTHCARE EXPENDITURE AND MORBIDITY. UNDERSTANDING THE PROCESSES INVOLVED IS KEY IF NEW THERAPEUTIC APPROACHES ARE TO BE DEVELOPED. EVIDENCE IS ACCUMULATING THAT CHRONIC DISEASES SUCH AS ASTHMA ARE ASSOCIATED WITH TEMPORAL AND SPATIAL ALTERATIONS IN THE PATTERN OF INFLAMMATORY GENE EXPRESSION WITHIN THE AIRWAYS. EXPRESSION OF THESE GENES CAN BE REGULATED BY TRANSCRIPTIONAL, POSTTRANSCRIPTIONAL, TRANSLATIONAL AND EPIGENETIC MECHANISMS. IT IS WELL ESTABLISHED THAT BINDING OF ACTIVATED TRANSCRIPTION FACTORS TO SPECIFIC INDUCIBLE GENE PROMOTER SITES IS TIGHTLY CONTROLLED BY CHROMATIN STATE AS A RESULT OF HISTONE MODIFICATIONS, PARTICULARLY THE BALANCE BETWEEN HISTONE ACETYLATION AND DEACETYLATION [1]. THE INTERACTION BETWEEN TRANSCRIPTION FACTORS AND THE PROMOTER IS KEY TO THE DIVERSIFICATION OF GENE EXPRESSION IN A TIME DEPENDENT MANNER LEADING TO ALTERED GENE EXPRESSION PROFILES. ALTERATIONS OF THE ACCESSIBILITY OF TRANSCRIPTION FACTORS TO THE DNA CAN HAVE RESIDING EFFECTS UPON GENE TRANSCRIPTION. THIS REVIEW WILL FOCUS ON THE REGULATION OF SEVERAL GROUPS OF KEY GENES WHICH ARE INVOLVED IN CHRONIC AIRWAY INFLAMMATION AND REMODELLING IN ASTHMA DRAWING MAINLY FROM OUR EXPERIENCE OF STUDYING THESE PROCESSES IN AIRWAY SMOOTH MUSCLE CELLS. AN OVERVIEW IS SHOWN IN FIGURE 1. 2011 15 2308 34 EPIGENETIC REGULATION OF CHEMOKINE (CC-MOTIF) LIGAND 2 IN INFLAMMATORY DISEASES. APPROPRIATE RESPONSES TO INFLAMMATION ARE CONDUCIVE TO PATHOGEN ELIMINATION AND TISSUE REPAIR, WHILE UNCONTROLLED INFLAMMATORY REACTIONS ARE LIKELY TO RESULT IN THE DAMAGE OF TISSUES. CHEMOKINE (CC-MOTIF) LIGAND 2 (CCL2) IS THE MAIN CHEMOKINE AND ACTIVATOR OF MONOCYTES, MACROPHAGES, AND NEUTROPHILS. CCL2 PLAYED A KEY ROLE IN AMPLIFYING AND ACCELERATING THE INFLAMMATORY CASCADE AND IS CLOSELY RELATED TO CHRONIC NON-CONTROLLABLE INFLAMMATION (CIRRHOSIS, NEUROPATHIC PAIN, INSULIN RESISTANCE, ATHEROSCLEROSIS, DEFORMING ARTHRITIS, ISCHEMIC INJURY, CANCER, ETC.). THE CRUCIAL REGULATORY ROLES OF CCL2 MAY PROVIDE POTENTIAL TARGETS FOR THE TREATMENT OF INFLAMMATORY DISEASES. THEREFORE, WE PRESENTED A REVIEW OF THE REGULATORY MECHANISMS OF CCL2. GENE EXPRESSION IS LARGELY AFFECTED BY THE STATE OF CHROMATIN. DIFFERENT EPIGENETIC MODIFICATIONS, INCLUDING DNA METHYLATION, POST-TRANSLATIONAL MODIFICATION OF HISTONES, HISTONE VARIANTS, ATP-DEPENDENT CHROMATIN REMODELLING, AND NON-CODING RNA, COULD AFFECT THE 'OPEN' OR 'CLOSED' STATE OF DNA, AND THEN SIGNIFICANTLY AFFECT THE EXPRESSION OF TARGET GENES. SINCE MOST EPIGENETIC MODIFICATIONS ARE PROVEN TO BE REVERSIBLE, TARGETING THE EPIGENETIC MECHANISMS OF CCL2 IS EXPECTED TO BE A PROMISING THERAPEUTIC STRATEGY FOR INFLAMMATORY DISEASES. THIS REVIEW FOCUSES ON THE EPIGENETIC REGULATION OF CCL2 IN INFLAMMATORY DISEASES. 2023 16 2228 30 EPIGENETIC MODIFICATIONS OF HISTONES IN PERIODONTAL DISEASE. PERIODONTITIS IS A CHRONIC INFECTIOUS DISEASE DRIVEN BY DYSBIOSIS, AN IMBALANCE BETWEEN COMMENSAL BACTERIA AND THE HOST ORGANISM. PERIODONTITIS IS A LEADING CAUSE OF TOOTH LOSS IN ADULTS AND OCCURS IN ABOUT 50% OF THE US POPULATION. IN ADDITION TO THE CLINICAL CHALLENGES ASSOCIATED WITH TREATING PERIODONTITIS, THE PROGRESSION AND CHRONIC NATURE OF THIS DISEASE SERIOUSLY AFFECT HUMAN HEALTH. EMERGING EVIDENCE SUGGESTS THAT PERIODONTITIS IS ASSOCIATED WITH MECHANISMS BEYOND BACTERIA-INDUCED PROTEIN AND TISSUE DEGRADATION. HERE, WE HYPOTHESIZE THAT BACTERIA ARE ABLE TO INDUCE EPIGENETIC MODIFICATIONS IN ORAL EPITHELIAL CELLS MEDIATED BY HISTONE MODIFICATIONS. IN THIS STUDY, WE FOUND THAT DYSBIOSIS IN VIVO LED TO EPIGENETIC MODIFICATIONS, INCLUDING ACETYLATION OF HISTONES AND DOWNREGULATION OF DNA METHYLTRANSFERASE 1. IN ADDITION, IN VITRO EXPOSURE OF ORAL EPITHELIAL CELLS TO LIPOPOLYSACCHARIDES RESULTED IN HISTONE MODIFICATIONS, ACTIVATION OF TRANSCRIPTIONAL COACTIVATORS, SUCH AS P300/CBP, AND ACCUMULATION OF NUCLEAR FACTOR-KAPPAB (NF-KAPPAB). GIVEN THAT ORAL EPITHELIAL CELLS ARE THE FIRST LINE OF DEFENSE FOR THE PERIODONTIUM AGAINST BACTERIA, WE ALSO EVALUATED WHETHER ACTIVATION OF PATHOGEN RECOGNITION RECEPTORS INDUCED HISTONE MODIFICATIONS. WE FOUND THAT ACTIVATION OF THE TOLL-LIKE RECEPTORS 1, 2, AND 4 AND THE NUCLEOTIDE-BINDING OLIGOMERIZATION DOMAIN PROTEIN 1 INDUCED HISTONE ACETYLATION IN ORAL EPITHELIAL CELLS. OUR FINDINGS CORROBORATE THE EMERGING CONCEPT THAT EPIGENETIC MODIFICATIONS PLAY A ROLE IN THE DEVELOPMENT OF PERIODONTITIS. 2016 17 5560 37 ROLE OF HISTONE DEACETYLASE 2 IN EPIGENETICS AND CELLULAR SENESCENCE: IMPLICATIONS IN LUNG INFLAMMAGING AND COPD. HISTONE DEACETYLASE 2 (HDAC2) IS A CLASS I HISTONE DEACETYLASE THAT REGULATES VARIOUS CELLULAR PROCESSES, SUCH AS CELL CYCLE, SENESCENCE, PROLIFERATION, DIFFERENTIATION, DEVELOPMENT, APOPTOSIS, AND GLUCOCORTICOID FUNCTION IN INHIBITING INFLAMMATORY RESPONSE. HDAC2 HAS BEEN SHOWN TO PROTECT AGAINST DNA DAMAGE RESPONSE AND CELLULAR SENESCENCE/PREMATURE AGING VIA AN EPIGENETIC MECHANISM IN RESPONSE TO OXIDATIVE STRESS. THESE PHENOMENA ARE OBSERVED IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). HDAC2 IS POSTTRANSLATIONALLY MODIFIED BY OXIDATIVE/CARBONYL STRESS IMPOSED BY CIGARETTE SMOKE AND OXIDANTS, LEADING TO ITS REDUCTION VIA AN UBIQUITINATION-PROTEASOME DEPENDENT DEGRADATION IN LUNGS OF PATIENTS WITH COPD. IN THIS PERSPECTIVE, WE HAVE DISCUSSED THE ROLE OF HDAC2 POSTTRANSLATIONAL MODIFICATIONS AND ITS ROLE IN REGULATION OF INFLAMMATION, HISTONE/DNA EPIGENETIC MODIFICATIONS, DNA DAMAGE RESPONSE, AND CELLULAR SENESCENCE, PARTICULARLY IN INFLAMMAGING, AND DURING THE DEVELOPMENT OF COPD. WE HAVE ALSO DISCUSSED THE POTENTIAL DIRECTIONS FOR FUTURE TRANSLATIONAL RESEARCH AVENUES IN MODULATING LUNG INFLAMMAGING AND CELLULAR SENESCENCE BASED ON EPIGENETIC CHROMATIN MODIFICATIONS IN DISEASES ASSOCIATED WITH INCREASED OXIDATIVE STRESS. 2012 18 3527 24 IL-6 ENHANCES THE NUCLEAR TRANSLOCATION OF DNA CYTOSINE-5-METHYLTRANSFERASE 1 (DNMT1) VIA PHOSPHORYLATION OF THE NUCLEAR LOCALIZATION SEQUENCE BY THE AKT KINASE. THE EPIGENETIC PROGRAMMING OF GENOMIC DNA IS ACCOMPLISHED, IN PART, BY SEVERAL DNA CYTOSINE-5-METHYLTRANSFERASES THAT ACT BY COVALENTLY MODIFYING CYTOSINES WITH THE ADDITION OF A METHYL GROUP. THIS COVALENT MODIFICATION IS MAINTAINED BY THE DNA CYTOSINE-5-METHYLTRANSFERASE-1 ENZYME (DNMT1), WHICH IS CAPABLE OF ACTING IN CONCERT WITH OTHER SIMILAR ENZYMES TO SILENCE IMPORTANT TUMOR SUPPRESSOR GENES. IL-6 IS A MULTIFUNCTIONAL MEDIATOR OF INFLAMMATION, ACTING THROUGH SEVERAL MAJOR SIGNALING CASCADES, INCLUDING THE PHOSPHATIDYLINOSITOL-3-KINASE PATHWAY (PI-3-K), WHICH ACTIVATES PROTEIN KINASE B (AKT/PKB) DOWNSTREAM. HERE, WE SHOW THAT THE SUBCELLULAR LOCALIZATION OF DNMT1 CAN BE ALTERED BY THE ADDITION OF IL-6, INCREASING THE RATE OF NUCLEAR TRANSLOCATION OF THE ENZYME FROM THE CYTOSOLIC COMPARTMENT. THE MECHANISM OF NUCLEAR TRANSLOCATION OF DNMT1 IS GREATLY ENHANCED BY PHOSPHORYLATION OF THE DNMT1 NUCLEAR LOCALIZATION SIGNAL (NLS) BY PKB/AKT KINASE. MUTAGENIC ALTERATION OF THE TWO AKT TARGET AMINO ACIDS WITHIN THE NLS RESULTS IN A MAJOR LOSS OF DNMT1 NUCLEAR TRANSLOCATION, WHILE THE CREATION OF A "PHOSPHO-MIMIC" AMINO ACID (MUTATION TO ACIDIC RESIDUES) RESTORES THIS COMPARTMENTATION ABILITY. THESE OBSERVATIONS SUGGEST AN INTERESTING HYPOTHESIS REGARDING HOW MEDIATORS OF CHRONIC INFLAMMATION MAY DISTURB THE DELICATE BALANCE OF CELLULAR COMPARTMENTALIZATION OF IMPORTANT PROTEINS, AND REVEALS A POTENTIAL MECHANISM FOR THE INDUCTION OR ENHANCEMENT OF TUMOR GROWTH VIA ALTERATION OF THE COMPONENTS INVOLVED IN THE EPIGENETIC PROGRAMMING OF A CELL. 2007 19 6839 31 [LUNG CANCER AND ITS EPIGENETICS ASSOCIATION WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE]. LUNG CANCER AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) ARE THE LEADING CAUSES OF MORBIDITY AND MORTALITY WORLDWIDE. DEVELOPMENT OF LUNG CANCER INVOLVES BOTH GENETIC AND ENVIRONMENT FACTORS. IN ADDITION TO GENETIC ALTERATIONS, EPIGENETIC MECHANISM IS CLOSELY INVOLVED IN PATHOGENESIS OF LUNG CANCER. CHARACTERIZED BY AN ABNORMAL PERSISTENT INFLAMMATORY RESPONSE TO NOXIOUS ENVIRONMENTAL STIMULATION, COPD HAS SHOWN TO INCREASE THE SUSCEPTIBILITY FOR LUNG TUMORIGENESIS IN PREVIOUS RESEARCH. CURRENT RESEARCH ON EPIGENETICS OF LUNG CANCER AND COPD HAS FOCUSED ON ABERRANT DNA METHYLATION, HISTONE ACETYLATION AND NON-CODING RNAS REGULATION. THE ABERRANT DNA METHYLATION ASSOCIATED WITH LUNG CANCER AND COPD HAS INCLUDED OVEREXPRESSION OF DNA METHYLTRANSFERASE, GLOBAL DNA HYPOMETHYLATION AND DNA HYPERMETHYLATION IN PROMOTER REGIONS, WHILE HISTONE ACETYLATION AND HISTONE METHYLATION ARE THE MAJOR CHANGES FOR HISTONE MODIFICATION, IN WHICH HISTONE ACETYLTRANSFERASES, HISTONE DEACETYLASES, HISTONE METHYLTRANSFERASES AND HISTONE DEMETHYLASES PLAY THE MOST IMPORTANT ROLES. RNA INTERFERENCE AND MICRORNAS ARE BOTH HOT TOPICS OF RESEARCH ON NON-CODING RNAS REGULATION. UNDERSTANDING OF CONCURRENT EPIGENETIC ALTERATIONS IN THE PATHOGENESIS OF LUNG CANCER AND COPD MAY FACILITATE IDENTIFICATION OF SPECIFIC THERAPEUTIC TARGETS AND DEVELOPMENT OF EFFECTIVE TREATMENT. 2013 20 4768 31 NUCLEAR EFFECTS OF ETHANOL-INDUCED PROTEASOME INHIBITION IN LIVER CELLS. ALCOHOL INGESTION CAUSES ALTERATION IN SEVERAL CELLULAR MECHANISMS, AND LEADS TO INFLAMMATION, APOPTOSIS, IMMUNOLOGICAL RESPONSE DEFECTS, AND FIBROSIS. THESE PHENOMENA ARE ASSOCIATED WITH SIGNIFICANT CHANGES IN THE EPIGENETIC MECHANISMS, AND SUBSEQUENTLY, TO LIVER CELL MEMORY. THE UBIQUITIN-PROTEASOME PATHWAY IS ONE OF THE VITAL PATHWAYS IN THE CELL THAT BECOMES DYSFUNCTIONAL AS A RESULT OF CHRONIC ETHANOL CONSUMPTION. INHIBITION OF THE PROTEASOME ACTIVITY IN THE NUCLEUS CAUSES CHANGES IN THE TURNOVER OF TRANSCRIPTIONAL FACTORS, HISTONE MODIFYING ENZYMES, AND THEREFORE, AFFECTS EPIGENETIC MECHANISMS. ALCOHOL CONSUMPTION HAS BEEN ASSOCIATED WITH AN INCREASE IN HISTONE ACETYLATION AND A DECREASE IN HISTONE METHYLATION, WHICH LEADS TO GENE EXPRESSION CHANGES. DNA AND HISTONE MODIFICATIONS THAT RESULT FROM ETHANOL-INDUCED PROTEASOME INHIBITION ARE KEY PLAYERS IN REGULATING GENE EXPRESSION, ESPECIALLY GENES INVOLVED IN THE CELL CYCLE, IMMUNOLOGICAL RESPONSES, AND METABOLISM OF ETHANOL. THE PRESENT REVIEW HIGHLIGHTS THE CONSEQUENCES OF ETHANOL-INDUCED PROTEASOME INHIBITION IN THE NUCLEUS OF LIVER CELLS THAT ARE CHRONICALLY EXPOSED TO ETHANOL. 2009