1 3644 101 INCREASED LEVELS OF ENDOGENOUS RETROVIRUSES TRIGGER FIBROINFLAMMATION AND PLAY A ROLE IN KIDNEY DISEASE DEVELOPMENT. INFLAMMATION IS A COMMON FEATURE OF ALL FORMS OF CHRONIC KIDNEY DISEASE; HOWEVER, THE UNDERLYING MECHANISM REMAINS POORLY UNDERSTOOD. EVOLUTIONARILY INHERITED ENDOGENOUS RETROVIRUSES (ERVS) HAVE THE POTENTIAL TO TRIGGER AN IMMUNE REACTION. COMPREHENSIVE RNA-SEQUENCING OF CONTROL AND DISEASED KIDNEYS FROM HUMAN AND MOUSE DISEASE MODELS INDICATED HIGHER EXPRESSION OF TRANSPOSABLE ELEMENTS (TES) AND ERVS IN DISEASED KIDNEYS. LOSS OF CYTOSINE METHYLATION CAUSING EPIGENETIC DEREPRESSION LIKELY CONTRIBUTES TO AN INCREASE IN ERV LEVELS. GENETIC DELETION/PHARMACOLOGICAL INHIBITION OF DNA METHYLTRANSFERASE 1 (DNMT1) INDUCES ERV EXPRESSION. IN CULTURED KIDNEY TUBULE CELLS, ERVS ELICIT THE ACTIVATION OF CYTOSOLIC NUCLEOTIDE SENSORS SUCH AS RIG-I, MDA5, AND STING. ERVS EXPRESSIONS IN KIDNEY TUBULES TRIGGER RIG-I/STING, AND CYTOKINE EXPRESSION, AND CORRELATE WITH THE PRESENCE OF IMMUNE CELLS. GENETIC DELETION OF RIG-I OR STING OR TREATMENT WITH REVERSE TRANSCRIPTASE INHIBITOR AMELIORATES KIDNEY FIBROINFLAMMATION. OUR DATA INDICATE AN IMPORTANT ROLE OF EPIGENETIC DEREPRESSION-INDUCED ERV ACTIVATION TRIGGERING RENAL FIBROINFLAMMATION. 2023 2 3798 26 INTERPLAY BETWEEN ACTIVATION OF ENDOGENOUS RETROVIRUSES AND INFLAMMATION AS COMMON PATHOGENIC MECHANISM IN NEUROLOGICAL AND PSYCHIATRIC DISORDERS. HUMAN ENDOGENOUS RETROVIRUSES (ERVS) ARE ANCESTORIAL RETROVIRAL ELEMENTS THAT WERE INTEGRATED INTO OUR GENOME THROUGH GERMLINE INFECTIONS AND INSERTIONS DURING EVOLUTION. THEY HAVE REPEATEDLY BEEN IMPLICATED IN THE AETIOLOGY AND PATHOPHYSIOLOGY OF NUMEROUS HUMAN DISORDERS, PARTICULARLY IN THOSE THAT AFFECT THE CENTRAL NERVOUS SYSTEM. IN ADDITION TO THE KNOWN ASSOCIATION OF ERVS WITH MULTIPLE SCLEROSIS AND AMYOTROPHIC LATERAL SCLEROSIS, A GROWING NUMBER OF STUDIES LINKS THE INDUCTION AND EXPRESSION OF THESE RETROVIRAL ELEMENTS WITH THE ONSET AND SEVERITY OF NEURODEVELOPMENTAL AND PSYCHIATRIC DISORDERS. ALTHOUGH THESE DISORDERS DIFFER IN TERMS OF OVERALL DISEASE PATHOLOGY AND CAUSALITIES, A CERTAIN DEGREE OF (SUBCLINICAL) CHRONIC INFLAMMATION CAN BE IDENTIFIED IN ALL OF THEM. BASED ON THESE COMMONALITIES, WE DISCUSS THE BIDIRECTIONAL RELATIONSHIP BETWEEN ERV EXPRESSION AND INFLAMMATION AND HIGHLIGHT THAT NUMEROUS ENTRY POINTS TO THIS RECIPROCAL SEQUENCE OF EVENTS EXIST, INCLUDING INITIAL INFECTIONS WITH ERV-ACTIVATING PATHOGENS, EXPOSURE TO NON-INFECTIOUS INFLAMMATORY STIMULI, AND CONDITIONS IN WHICH EPIGENETIC SILENCING OF ERV ELEMENTS IS DISRUPTED. 2023 3 3845 19 IS AGING A "RETRO"SPECTIVE EVENT? REACTIVATION OF ENDOGENOUS RETROVIRUSES (ERVS), THE RELICS OF ANCIENT INFECTIONS, HAS BEEN IMPLICATED IN A NUMBER OF DISEASE CONTEXTS. IN THIS ISSUE OF CELL, LIU ET AL. SHOW HOW REACTIVATION OF ERVS IN OLD AGE CAN INDUCE SENESCENCE. THIS AWAKENING OF ERVS IS ASSOCIATED WITH THEIR EPIGENETIC DEREPRESSION AND CONTRIBUTES TO AGE-ASSOCIATED CHRONIC INFLAMMATION. 2023 4 4558 22 MUTATIONS IN THE NF-KAPPAB SIGNALING PATHWAY: IMPLICATIONS FOR HUMAN DISEASE. THE NUCLEAR FACTOR-KAPPA B (NF-KAPPAB) SIGNALING PATHWAY IS A MULTI-COMPONENT PATHWAY THAT REGULATES THE EXPRESSION OF HUNDREDS OF GENES THAT ARE INVOLVED IN DIVERSE AND KEY CELLULAR AND ORGANISMAL PROCESSES, INCLUDING CELL PROLIFERATION, CELL SURVIVAL, THE CELLULAR STRESS RESPONSE, INNATE IMMUNITY AND INFLAMMATION. NOT SURPRISINGLY, MIS-REGULATION OF THE NF-KAPPAB PATHWAY, EITHER BY MUTATION OR EPIGENETIC MECHANISMS, IS INVOLVED IN MANY HUMAN AND ANIMAL DISEASES, ESPECIALLY ONES ASSOCIATED WITH CHRONIC INFLAMMATION, IMMUNODEFICIENCY OR CANCER. THIS REVIEW DESCRIBES HUMAN DISEASES IN WHICH MUTATIONS IN THE COMPONENTS OF THE CORE NF-KAPPAB SIGNALING PATHWAY HAVE BEEN IMPLICATED AND DISCUSSES THE MOLECULAR MECHANISMS BY WHICH THESE ALTERATIONS IN NF-KAPPAB SIGNALING ARE LIKELY TO CONTRIBUTE TO THE DISEASE PATHOLOGY. THESE MUTATIONS CAN BE GERMLINE OR SOMATIC AND INCLUDE GENE AMPLIFICATION (E.G., REL), POINT MUTATIONS AND DELETIONS (REL, NFKB2, IKBA, CYLD, NEMO) AND CHROMOSOMAL TRANSLOCATIONS (BCL-3). IN ADDITION, HUMAN GENETIC DISEASES ARE BRIEFLY DESCRIBED WHEREIN MUTATIONS AFFECT PROTEIN MODIFIERS OR TRANSDUCERS OF NF-KAPPAB SIGNALING OR DISRUPT NF-KAPPAB-BINDING SITES IN PROMOTERS/ENHANCERS. 2006 5 5571 30 ROLE OF MICRORNA 1207-5P AND ITS HOST GENE, THE LONG NON-CODING RNA PVT1, AS MEDIATORS OF EXTRACELLULAR MATRIX ACCUMULATION IN THE KIDNEY: IMPLICATIONS FOR DIABETIC NEPHROPATHY. DIABETIC NEPHROPATHY IS THE MOST COMMON CAUSE OF CHRONIC KIDNEY FAILURE AND END-STAGE RENAL DISEASE IN THE WESTERN WORLD. ONE OF THE MAJOR CHARACTERISTICS OF THIS DISEASE IS THE EXCESSIVE ACCUMULATION OF EXTRACELLULAR MATRIX (ECM) IN THE KIDNEY GLOMERULI. WHILE BOTH ENVIRONMENTAL AND GENETIC DETERMINANTS ARE RECOGNIZED FOR THEIR ROLE IN THE DEVELOPMENT OF DIABETIC NEPHROPATHY, EPIGENETIC FACTORS, SUCH AS DNA METHYLATION, LONG NON-CODING RNAS, AND MICRORNAS, HAVE ALSO RECENTLY BEEN FOUND TO UNDERLIE SOME OF THE BIOLOGICAL MECHANISMS, INCLUDING ECM ACCUMULATION, LEADING TO THE DISEASE. WE PREVIOUSLY FOUND THAT A LONG NON-CODING RNA, THE PLASMACYTOMA VARIANT TRANSLOCATION 1 (PVT1), INCREASES PLASMINOGEN ACTIVATOR INHIBITOR 1 (PAI-1) AND TRANSFORMING GROWTH FACTOR BETA 1 (TGF-BETA1) IN MESANGIAL CELLS, THE TWO MAIN CONTRIBUTORS TO ECM ACCUMULATION IN THE GLOMERULI UNDER HYPERGLYCEMIC CONDITIONS, AS WELL AS FIBRONECTIN 1 (FN1), A MAJOR ECM COMPONENT. HERE, WE REPORT THAT MIR-1207-5P, A PVT1-DERIVED MICRORNA, IS ABUNDANTLY EXPRESSED IN KIDNEY CELLS, AND IS UPREGULATED BY GLUCOSE AND TGF-BETA1. WE ALSO FOUND THAT LIKE PVT1, MIR-1207-5P INCREASES EXPRESSION OF TGF-BETA1, PAI-1, AND FN1 BUT IN A MANNER THAT IS INDEPENDENT OF ITS HOST GENE. IN ADDITION, REGULATION OF MIR-1207-5P EXPRESSION BY GLUCOSE AND TGFBETA1 IS INDEPENDENT OF PVT1. THESE RESULTS PROVIDE EVIDENCE SUPPORTING IMPORTANT ROLES FOR MIR-1207-5P AND ITS HOST GENE IN THE COMPLEX PATHOGENESIS OF DIABETIC NEPHROPATHY. 2013 6 6230 20 THE LONG NONCODING RNA LANDSCAPE IN HYPOXIC AND INFLAMMATORY RENAL EPITHELIAL INJURY. LONG NONCODING RNAS (LNCRNAS) ARE EMERGING AS KEY SPECIES-SPECIFIC REGULATORS OF CELLULAR AND DISEASE PROCESSES. TO IDENTIFY POTENTIAL LNCRNAS RELEVANT TO ACUTE AND CHRONIC RENAL EPITHELIAL INJURY, WE PERFORMED UNBIASED WHOLE TRANSCRIPTOME PROFILING OF HUMAN PROXIMAL TUBULAR EPITHELIAL CELLS (PTECS) IN HYPOXIC AND INFLAMMATORY CONDITIONS. RNA SEQUENCING REVEALED THAT THE PROTEIN-CODING AND NONCODING TRANSCRIPTOMIC LANDSCAPE DIFFERED BETWEEN HYPOXIA-STIMULATED AND CYTOKINE-STIMULATED HUMAN PTECS. HYPOXIA- AND INFLAMMATION-MODULATED LNCRNAS WERE PRIORITIZED FOR FOCUSED FOLLOWUP ACCORDING TO THEIR DEGREE OF INDUCTION BY THESE STRESS STIMULI, THEIR EXPRESSION IN HUMAN KIDNEY TISSUE, AND WHETHER EXPOSURE OF HUMAN PTECS TO PLASMA OF CRITICALLY ILL SEPSIS PATIENTS WITH ACUTE KIDNEY INJURY MODULATED THEIR EXPRESSION. FOR THREE LNCRNAS (MIR210HG, LINC-ATP13A4-8, AND LINC-KIAA1737-2) THAT FULFILLED OUR CRITERIA, WE VALIDATED THEIR EXPRESSION PATTERNS, EXAMINED THEIR LOCI FOR CONSERVATION AND SYNTENY, AND DEFINED THEIR ASSOCIATED EPIGENETIC MARKS. THE LNCRNA LANDSCAPE CHARACTERIZED HERE PROVIDES INSIGHTS INTO NOVEL TRANSCRIPTOMIC VARIATIONS IN THE RENAL EPITHELIAL CELL RESPONSE TO HYPOXIC AND INFLAMMATORY STRESS. 2015 7 1902 21 ENHANCED EXPRESSION OF THE NUCLEAR ENVELOPE LAP2 TRANSCRIPTIONAL REPRESSORS IN NORMAL AND MALIGNANT ACTIVATED LYMPHOCYTES. EXTENSIVE RESEARCH IN RECENT YEARS HAS BROADENED THE FUNCTIONS OF NUCLEAR ENVELOPE PROTEINS BEYOND SIMPLY STABILIZING THE NUCLEUS ARCHITECTURE. PARTICULARLY, INTEGRAL NUCLEAR MEMBRANE PROTEINS, SUCH AS THE ALTERNATIVE SPLICED ISOFORMS OF LAMINA-ASSOCIATED POLYPEPTIDE 2 (LAP2), HAVE BEEN SHOWN TO BE IMPORTANT FOR THE INITIATION OF REPLICATION AND REPRESSION OF TRANSCRIPTION. THE LATTER IS REGULATED BY EPIGENETIC CHANGES, INDUCED BY THE BINDING OF LAP2BETA TO HISTONE DEACETYLASE-3 (HDAC3), RESULTING IN HISTONE H4 DEACETYLATION. INVOLVEMENT OF NUCLEAR ENVELOPE PROTEINS IN PATHOLOGICAL PROLIFERATIVE CONDITIONS, MAINLY THOSE INVOLVING ABNORMAL RECRUITMENT AND ACTIVATION OF HDACS, IS STILL UNKNOWN. IN THIS PAPER, WE SHOW THAT VARIOUS NUCLEAR ENVELOPE PROTEINS ARE HIGHLY EXPRESSED IN NORMAL AND MALIGNANT ACTIVATED LYMPHOCYTES. SPECIFICALLY, RAPIDLY REPLICATING CELLS OF VARIOUS HEMATOLOGICAL MALIGNANCIES HIGHLY EXPRESS LAP2BETA, WHILE SLOWLY PROLIFERATING MALIGNANT CELLS OF CHRONIC MALIGNANT HEMATOLOGICAL DISEASES DO NOT. TAKING TOGETHER THE ELEVATED EXPRESSION OF LAP2BETA IN HIGHLY PROLIFERATIVE MALIGNANT CELLS WITH ITS KNOWN ABILITY TO MODIFY HISTONES THROUGH BINDING WITH HDAC3 RAISES THE POSSIBILITY OF ITS ROLE IN HEMATOLOGICAL MALIGNANCIES INVOLVING ABERRANT ACTIVITY OF HDAC3. BASED ON OUR PRESENTED RESULTS, WE BELIEVE THAT THE LAP2-HDAC REGULATORY PATHWAY SHOULD BE STUDIED AS A NEW TARGET FOR RATIONAL THERAPY. 2007 8 984 29 CHRONIC PSYCHOLOGICAL STRESS ALTERS GENE EXPRESSION IN RAT COLON EPITHELIAL CELLS PROMOTING CHROMATIN REMODELING, BARRIER DYSFUNCTION AND INFLAMMATION. CHRONIC STRESS IS COMMONLY ASSOCIATED WITH ENHANCED ABDOMINAL PAIN (VISCERAL HYPERSENSITIVITY), BUT THE CELLULAR MECHANISMS UNDERLYING HOW CHRONIC STRESS INDUCES VISCERAL HYPERSENSITIVITY ARE POORLY UNDERSTOOD. IN THIS STUDY, WE EXAMINED CHANGES IN GENE EXPRESSION IN COLON EPITHELIAL CELLS FROM A RAT MODEL USING RNA-SEQUENCING TO EXAMINE STRESS-INDUCED CHANGES TO THE TRANSCRIPTOME. FOLLOWING CHRONIC STRESS, THE MOST SIGNIFICANTLY UP-REGULATED GENES INCLUDED ATG16L1, COQ10B, DCAF13, NAT2, PTBP2, RRAS2, SPINK4 AND DOWN-REGULATED GENES INCLUDING ABAT, CITED2, CNNM2, DAB2IP, PLEKHM1, SCD2, AND TAB2. THE PRIMARY ALTERED BIOLOGICAL PROCESSES REVEALED BY NETWORK ENRICHMENT ANALYSIS WERE INFLAMMATION/IMMUNE RESPONSE, TISSUE MORPHOGENESIS AND DEVELOPMENT, AND NUCLEOSOME/CHROMATIN ASSEMBLY. THE MOST SIGNIFICANTLY DOWN-REGULATED PROCESS WAS THE DIGESTIVE SYSTEM DEVELOPMENT/FUNCTION, WHEREAS THE MOST SIGNIFICANTLY UP-REGULATED PROCESSES WERE INFLAMMATORY RESPONSE, ORGANISMAL INJURY, AND CHROMATIN REMODELING MEDIATED BY H3K9 METHYLATION. FURTHERMORE, A SUBPOPULATION OF STRESSED RATS DEMONSTRATED VERY SIGNIFICANTLY ALTERED GENE EXPRESSION AND TRANSCRIPT ISOFORMS, ENRICHED FOR THE DIFFERENTIAL EXPRESSION OF GENES INVOLVED IN THE INFLAMMATORY RESPONSE, INCLUDING UPREGULATION OF CYTOKINE AND CHEMOKINE RECEPTOR GENE EXPRESSION COUPLED WITH DOWNREGULATION OF EPITHELIAL ADHERENS AND TIGHT JUNCTION MRNAS. IN SUMMARY, THESE FINDINGS SUPPORT THAT CHRONIC STRESS IS ASSOCIATED WITH INCREASED LEVELS OF CYTOKINES AND CHEMOKINES, THEIR DOWNSTREAM SIGNALING PATHWAYS COUPLED TO DYSREGULATION OF INTESTINAL CELL DEVELOPMENT AND FUNCTION. EPIGENETIC REGULATION OF CHROMATIN REMODELING LIKELY PLAYS A PROMINENT ROLE IN THIS PROCESS. RESULTS ALSO SUGGEST THAT SUPER ENHANCERS PLAY A PRIMARY ROLE IN CHRONIC STRESS-ASSOCIATED INTESTINAL BARRIER DYSFUNCTION. 2022 9 3948 25 LNCRNA-CD160 DECREASES THE IMMUNITY OF CD8(+) T CELLS THROUGH EPIGENETIC MECHANISMS IN HEPATITIS B VIRUS INFECTION. THE TRANSFER AND DEVELOPMENT OF CHRONIC HEPATITIS B VIRUS (HBV) INFECTION IS ASSOCIATED WITH THE T CELL IMMUNE RESPONSE, THEREFORE INVESTIGATING THE KEY REGULATORS OF CELL IMMUNE RESPONSE IS NEEDED TO IMPROVE CHRONIC HBV TREATMENT. BLOOD SAMPLES FROM PATIENTS WITH CHRONIC HBV INFECTION WERE USED TO CONFIRM THE CORRELATION BETWEEN HBV INFECTION STAGE AND CD160 RECEPTOR EXPRESSION LEVELS IN CD8(+) T CELLS, THE CD8(+) T CELLS ARE USED TO RESEARCH THE MECHANISM OF T CELL IMMUNE RESPONSE MODULATION, MOREOVER, C3H/HEN MICE WITH REDUCED CD160 EXPRESSION LEVELS WERE USED TO INVESTIGATE THE ASSOCIATION BETWEEN LONG NON-CODING (LNC)RNA-CD160 AND HBV INFECTION. LONG NON-CODING (LNC)RNA-CD160 AND HISTONE-MODIFICATION ENZYME GENE HISTONE DEACETYLASE 11 (HDAC11) EXPRESSION LEVELS WERE NEGATIVELY ASSOCIATED WITH CD160 EXPRESSION. LNCRNA-CD160 CAN INHIBIT THE SECRETION OF IFN-GAMMA AND TNF-ALPHA THROUGH HDAC11 RECRUITMENT AND BIND TO HDAC11 TO FORM A COMPLEX ON THE PROMOTERS OF IFN-GAMMA AND TNF-ALPHA. THE HDAC11, IFN-GAMMA AND TNF-ALPHA FORM A COMPLEX AND ENHANCE THE METHYLATION OF H3K9ME1, CHROMATIN CHANGES INTO THE HETEROCHROMATIN AND THE TRANSCRIPTION OF IFN-GAMMA AND TNF-ALPHA IS BLOCKED; MOREOVER, THE HDAC11/IFN-GAMMA/TNF-ALPHA COMPLEX CAN ALSO INHIBIT THE SECRETION OF IFN-GAMMA AND TNF-ALPHA IN CD160(-) CD8(+) T CELLS AND SUPPRESSES THE FUNCTION OF CD8(+) T CELLS. FURTHERMORE, SMALL INTERFERING RNA TARGETING LNCRNA-CD160 CAN BLOCK HBV INFECTION PROGRESSION. LNCRNA-CD160 ACTS AS AN IMMUNE SUPPRESSIVE FACTOR AND IS EXPRESSED AT A HIGH LEVEL IN PERIPHERAL BLOOD CD8(+) T CELLS OF HBV INFECTED PATIENTS. FURTHERMORE, HIGH EXPRESSION LEVELS OF LNCRNA-CD160 CAN CONTRIBUTE TO THE INHIBITION OF IFN-GAMMA AND TNF-ALPHA SECRETION IN CD8(+) T CELLS AND DECREASE THE IMMUNE RESPONSE OF CD8(+) T CELLS. THEREFORE, LNCRNA-CD160 MAY BECOME A NEW TARGET FOR IMMUNOTHERAPY OF CHRONIC HBV INFECTION IN THE FUTURE AND MAY PROVIDE A NEW THERAPEUTIC STRATEGY FOR THE TREATMENT OF HBV INFECTION. 2020 10 4362 31 MIR?152 REGULATES TGF?BETA1?INDUCED EPITHELIAL?MESENCHYMAL TRANSITION BY TARGETING HPIP IN TUBULAR EPITHELIAL CELLS. RENAL FIBROSIS IS A COMMON PATHOLOGICAL FEATURE OF CHRONIC KIDNEY DISEASES, AND THEIR DEVELOPMENT AND PROGRESSION ARE INFLUENCED BY EPIGENETIC MODIFICATIONS INCLUDING ABERRANT MICRORNA (MIRNA OR MIR) EXPRESSION. MIRNAS HAVE BEEN DEMONSTRATED TO MODULATE THE AGGRESSIVENESS OF VARIOUS CANCERS AND HAVE EMERGED AS POSSIBLE THERAPEUTIC AGENTS FOR THE MANAGEMENT OF RENAL FIBROSIS. TRANSFORMING GROWTH FACTOR BETA1 (TGF?BETA1)?INDUCED EPITHELIAL?MESENCHYMAL TRANSITION (EMT) OF TUBULAR EPITHELIAL CELLS SERVES A ROLE IN THE INITIATION AND PROGRESSION OF RENAL FIBROSIS. FURTHERMORE, RECENT RESULTS INDICATED THAT THE PROGRESSION OF EMT IS REVERSIBLE. THE PRESENT STUDY AIMED TO CLARIFY THE ROLE OF MIR?152 IN EMT OF THE TUBULAR EPITHELIAL CELL LINE HK?2, STIMULATED BY TGF?BETA1, USING IN VITRO TRANSFECTION WITH A MIR?152 MIMIC AND TO FURTHER INVESTIGATE THE UNDERLYING MECHANISM OF MIR?152 ACTIVITY. IN THE PRESENT STUDY, MIR?152 EXPRESSION WAS SIGNIFICANTLY REDUCED IN TGF?BETA1?TREATED HK?2 CELLS, ACCOMPANIED BY AN INCREASED EXPRESSION OF HEMATOPOIETIC PRE?B?CELL LEUKEMIA TRANSCRIPTION FACTOR (PBX)?INTERACTING PROTEIN (HPIP). ADDITIONALLY, MIR?152 OVEREXPRESSION INHIBITED TGF?BETA1?INDUCED EMT AND SUPPRESSED HPIP EXPRESSION BY DIRECTLY TARGETING THE 3' UNTRANSLATED REGION OF HPIP IN HK?2 CELLS. FURTHERMORE, UPREGULATION OF HPIP REVERSED MIR?152?MEDIATED INHIBITORY EFFECTS ON THE EMT. COLLECTIVELY, THE RESULTS SUGGEST THAT DOWNREGULATION OF MIR?152 INITIATES THE DEDIFFERENTIATION OF RENAL TUBULES AND PROGRESSION OF RENAL FIBROSIS, WHICH MAY PROVIDE IMPORTANT TARGETS FOR PREVENTION STRATEGIES OF RENAL FIBROSIS. 2018 11 6057 22 THE DARK SIDE OF REGULATORY T CELLS IN PSORIASIS. PSORIASIS IS A HEREDITARY DISEASE ELICITED BY CHRONIC ACTIVATION OF CUTANEOUS T CELLS. DELINEATING THE MECHANISTIC INTERPLAY OF THE CELL SUBSETS INVOLVED IS KEY TO DEVELOPING THE NEXT GENERATION OF EFFECTIVE TREATMENTS. IN THIS ISSUE, BOVENSCHEN ET AL. REPORT THAT REGULATORY T CELLS MAINTAIN A FINE BALANCE BETWEEN THE TRANSCRIPTION FACTORS FOXP3 AND RORGAMMAT. IN PATIENTS WITH PSORIASIS, TREGS READILY TURN INTO IL-17-EXPRESSING CELLS, THUS POTENTIALLY PERPETUATING THE INFLAMMATORY PROCESS THAT CHARACTERIZES THE DISEASE. RESULTS DEMONSTRATING THAT THE HISTONE/PROTEIN DEACETYLATION INHIBITOR TRICHOSTATIN A CAN BLOCK THIS CONVERSION SUGGEST THAT AN EPIGENETIC MODIFICATION MAY UNDERLIE REGULATORY T-CELL PLASTICITY. 2011 12 5153 24 PPP2R2B HYPERMETHYLATION CAUSES ACQUIRED APOPTOSIS DEFICIENCY IN SYSTEMIC AUTOIMMUNE DISEASES. CHRONIC INFLAMMATION CAUSES TARGET ORGAN DAMAGE IN PATIENTS WITH SYSTEMIC AUTOIMMUNE DISEASES. THE FACTORS THAT ALLOW THIS PROTRACTED RESPONSE ARE POORLY UNDERSTOOD. WE ANALYZED THE TRANSCRIPTIONAL REGULATION OF PPP2R2B (B55SS), A MOLECULE NECESSARY FOR THE TERMINATION OF THE IMMUNE RESPONSE, IN PATIENTS WITH AUTOIMMUNE DISEASES. ALTERED EXPRESSION OF B55SS CONDITIONED RESISTANCE TO CYTOKINE WITHDRAWAL-INDUCED DEATH (CWID) IN PATIENTS WITH AUTOIMMUNE DISEASES. THE IMPAIRED UPREGULATION OF B55SS WAS CAUSED BY INFLAMMATION-DRIVEN HYPERMETHYLATION OF SPECIFIC CYTOSINES LOCATED WITHIN A REGULATORY ELEMENT OF PPP2R2B PREVENTING CTCF BINDING. THIS PHENOTYPE COULD BE INDUCED IN HEALTHY T CELLS BY EXPOSURE TO TNF-ALPHA. OUR RESULTS REVEAL A GENE WHOSE EXPRESSION IS AFFECTED BY AN ACQUIRED DEFECT, THROUGH AN EPIGENETIC MECHANISM, IN THE SETTING OF SYSTEMIC AUTOIMMUNITY. BECAUSE FAILURE TO REMOVE ACTIVATED T CELLS THROUGH CWID COULD CONTRIBUTE TO AUTOIMMUNE PATHOLOGY, THIS MECHANISM ILLUSTRATES A VICIOUS CYCLE THROUGH WHICH AUTOIMMUNE INFLAMMATION CONTRIBUTES TO ITS OWN PERPETUATION. 2019 13 6294 30 THE PROINFLAMMATORY CYTOKINE TNFALPHA INDUCES DNA DEMETHYLATION-DEPENDENT AND -INDEPENDENT ACTIVATION OF INTERLEUKIN-32 EXPRESSION. IL-32 IS A CYTOKINE INVOLVED IN PROINFLAMMATORY IMMUNE RESPONSES TO BACTERIAL AND VIRAL INFECTIONS. HOWEVER, THE ROLE OF EPIGENETIC EVENTS IN THE REGULATION OF IL-32 GENE EXPRESSION IS UNDERSTUDIED. HERE WE SHOW THAT IL-32 IS REPRESSED BY DNA METHYLATION IN HEK293 CELLS. USING CHIP SEQUENCING, LOCUS-SPECIFIC METHYLATION ANALYSIS, CRISPR/CAS9-MEDIATED GENOME EDITING, AND RT-QPCR (QUANTITATIVE RT-PCR) AND IMMUNOBLOT ASSAYS, WE FOUND THAT SHORT-TERM TREATMENT (A FEW HOURS) WITH THE PROINFLAMMATORY CYTOKINE TUMOR NECROSIS FACTOR ALPHA (TNFALPHA) ACTIVATES IL-32 IN A DNA DEMETHYLATION-INDEPENDENT MANNER. IN CONTRAST, PROLONGED TNFALPHA TREATMENT (SEVERAL DAYS) INDUCED DNA DEMETHYLATION AT THE PROMOTER AND A CPG ISLAND IN THE IL-32 GENE IN A TET (TEN-ELEVEN TRANSLOCATION) FAMILY ENZYME- AND NF-KAPPAB-DEPENDENT MANNER. NOTABLY, THE HYPOMETHYLATION STATUS OF TRANSCRIPTIONAL REGULATORY ELEMENTS IN IL-32 WAS MAINTAINED FOR A LONG TIME (SEVERAL WEEKS), CAUSING ELEVATED IL-32 EXPRESSION EVEN IN THE ABSENCE OF TNFALPHA. CONSIDERING THAT IL-32 CAN, IN TURN, INDUCE TNFALPHA EXPRESSION, WE SPECULATE THAT SUCH FEEDFORWARD EVENTS MAY CONTRIBUTE TO THE TRANSITION FROM AN ACUTE INFLAMMATORY RESPONSE TO CHRONIC INFLAMMATION. 2019 14 4507 23 MRTF: BASIC BIOLOGY AND ROLE IN KIDNEY DISEASE. A LESSER KNOWN BUT CRUCIALLY IMPORTANT DOWNSTREAM EFFECT OF RHO FAMILY GTPASES IS THE REGULATION OF GENE EXPRESSION. THIS MAJOR ROLE IS MEDIATED VIA THE CYTOSKELETON, THE ORGANIZATION OF WHICH DICTATES THE NUCLEOCYTOPLASMIC SHUTTLING OF A SET OF TRANSCRIPTION FACTORS. CENTRAL AMONG THESE IS MYOCARDIN-RELATED TRANSCRIPTION FACTOR (MRTF), WHICH UPON ACTIN POLYMERIZATION TRANSLOCATES TO THE NUCLEUS AND BINDS TO ITS COGNATE PARTNER, SERUM RESPONSE FACTOR (SRF). THE MRTF/SRF COMPLEX THEN DRIVES A LARGE COHORT OF GENES INVOLVED IN CYTOSKELETON REMODELING, CONTRACTILITY, EXTRACELLULAR MATRIX ORGANIZATION AND MANY OTHER PROCESSES. ACCORDINGLY, MRTF, ACTIVATED BY A VARIETY OF MECHANICAL AND CHEMICAL STIMULI, AFFECTS A PLETHORA OF FUNCTIONS WITH PHYSIOLOGICAL AND PATHOLOGICAL RELEVANCE. THESE INCLUDE CELL MOTILITY, DEVELOPMENT, METABOLISM AND THUS METASTASIS FORMATION, INFLAMMATORY RESPONSES AND-PREDOMINANTLY-ORGAN FIBROSIS. THE AIM OF THIS REVIEW IS TWOFOLD: TO PROVIDE AN UP-TO-DATE SUMMARY ABOUT THE BASIC BIOLOGY AND REGULATION OF THIS VERSATILE TRANSCRIPTIONAL COACTIVATOR; AND TO HIGHLIGHT ITS PRINCIPAL INVOLVEMENT IN THE PATHOBIOLOGY OF KIDNEY DISEASE. ACTING THROUGH BOTH DIRECT TRANSCRIPTIONAL AND EPIGENETIC MECHANISMS, MRTF PLAYS A KEY (YET NOT FULLY APPRECIATED) ROLE IN THE INDUCTION OF A PROFIBROTIC EPITHELIAL PHENOTYPE (PEP) AS WELL AS IN FIBROBLAST-MYOFIBROBLAST TRANSITION, PRIME PATHOMECHANISMS IN CHRONIC KIDNEY DISEASE AND RENAL FIBROSIS. 2021 15 1293 27 DECREASED ERK AND JNK SIGNALING CONTRIBUTE TO GENE OVEREXPRESSION IN "SENESCENT" CD4+CD28- T CELLS THROUGH EPIGENETIC MECHANISMS. AN INFLAMMATORY AND CYTOTOXIC CD4+CD28- T CELL SUBSET INFILTRATES ATHEROSCLEROTIC PLAQUES AND IS IMPLICATED IN PLAQUE RUPTURE AND MYOCARDIAL INFARCTIONS. THIS PATHOLOGIC SUBSET DEVELOPS WITH REPLICATIVE STRESS AND IS FOUND IN PATIENTS WITH CHRONIC INFLAMMATORY DISEASES SUCH AS RA AS WELL AS WITH AGING. CD4+CD28- CELLS OVEREXPRESS GENES NORMALLY SUPPRESSED BY DNA METHYLATION IN CD4+CD28+ T CELLS, SUCH AS KIR, PERFORIN, AND CD70. HOW THIS SUBSET OVER EXPRESSES METHYLATION-SENSITIVE GENES IS UNKNOWN. DNA METHYLATION PATTERNS ARE MAINTAINED IN PROLIFERATING CELLS BY DNMTS, WHICH ARE UP-REGULATED DURING MITOSIS BY THE ERK AND JNK SIGNALING PATHWAYS. WE HYPOTHESIZED THAT DEFECTS IN THESE SIGNALING PATHWAYS CONTRIBUTE TO ALTERED GENE EXPRESSION IN HUMAN CD4+CD28- CELLS THROUGH EFFECTS ON DNA METHYLATION. WE REPORT THAT SIGNALING THROUGH THE ERK AND JNK PATHWAYS IS DECREASED IN CD4+CD28- RELATIVE TO CD4+CD28+ CELLS FROM THE SAME INDIVIDUALS AND THAT ERK AND JNK PATHWAY INHIBITION DECREASES DNMT1 AND -3A LEVELS, WHICH IN TURN, CAUSES DEMETHYLATION AND OVEREXPRESSION OF THE TNFSF7 (CD70) GENE. WE ALSO REPORT THAT CD4+CD28- T CELLS OVEREXPRESS PP5, A STRESS-INDUCED INHIBITOR OF THE ERK AND JNK SIGNALING PATHWAYS THAT MAY CONTRIBUTE TO THE SIGNALING DEFECTS. WE CONCLUDE THAT DECREASED ERK AND JNK SIGNALING IN THE CD4+CD28- SUBSET, ARISING WITH REPLICATIVE STRESS, CAN LEAD TO THE OVEREXPRESSION OF NORMALLY SUPPRESSED GENES THROUGH EFFECTS ON DNMTS AND CONSEQUENTLY, CHROMATIN STRUCTURE. 2010 16 3527 25 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 17 2373 31 EPIGENETIC REGULATION OF THE N-TERMINAL TRUNCATED ISOFORM OF MATRIX METALLOPROTEINASE-2 (NTT-MMP-2) AND ITS PRESENCE IN RENAL AND CARDIAC DISEASES. SEVERAL CLINICAL AND EXPERIMENTAL STUDIES HAVE DOCUMENTED A COMPELLING AND CRITICAL ROLE FOR THE FULL-LENGTH MATRIX METALLOPROTEINASE-2 (FL-MMP-2) IN ISCHEMIC RENAL INJURY, PROGRESSIVE RENAL FIBROSIS, AND DIABETIC NEPHROPATHY. A NOVEL N-TERMINAL TRUNCATED ISOFORM OF MMP-2 (NTT-MMP-2) WAS RECENTLY DISCOVERED, WHICH IS INDUCED BY HYPOXIA AND OXIDATIVE STRESS BY THE ACTIVATION OF A LATENT PROMOTER LOCATED IN THE FIRST INTRON OF THE MMP2 GENE. THIS NTT-MMP-2 ISOFORM IS ENZYMATICALLY ACTIVE BUT REMAINS INTRACELLULAR IN OR NEAR THE MITOCHONDRIA. IN THIS PERSPECTIVE ARTICLE, WE FIRST PRESENT THE FINDINGS ABOUT THE DISCOVERY OF THE NTT-MMP-2 ISOFORM, AND ITS FUNCTIONAL AND STRUCTURAL DIFFERENCES AS COMPARED WITH THE FL-MMP-2 ISOFORM. BASED ON PUBLICLY AVAILABLE EPIGENOMICS DATA FROM THE ENCYCLOPEDIA OF DNA ELEMENTS (ENCODE) PROJECT, WE PROVIDE INSIGHTS INTO THE EPIGENETIC REGULATION OF THE LATENT PROMOTER LOCATED IN THE FIRST INTRON OF THE MMP2 GENE, WHICH SUPPORT THE ACTIVATION OF THE NTT-MMP-2 ISOFORM. WE THEN FOCUS ON ITS FUNCTIONAL ASSESSMENT BY COVERING THE ALTERATIONS FOUND IN THE KIDNEY OF TRANSGENIC MICE EXPRESSING THE NTT-MMP-2 ISOFORM. NEXT, WE HIGHLIGHT RECENT FINDINGS REGARDING THE PRESENCE OF THE NTT-MMP-2 ISOFORM IN RENAL DYSFUNCTION, IN KIDNEY AND CARDIAC DISEASES, INCLUDING DAMAGE OBSERVED IN AGING, ACUTE ISCHEMIA-REPERFUSION INJURY (IRI), CHRONIC KIDNEY DISEASE, DIABETIC NEPHROPATHY, AND HUMAN RENAL TRANSPLANTS WITH DELAYED GRAFT FUNCTION. FINALLY, WE BRIEFLY DISCUSS HOW OUR INSIGHTS MAY GUIDE FURTHER EXPERIMENTAL AND CLINICAL STUDIES THAT ARE NEEDED TO ELUCIDATE THE UNDERLYING MECHANISMS AND THE ROLE OF THE NTT-MMP-2 ISOFORM IN RENAL DYSFUNCTION, WHICH MAY HELP TO ESTABLISH IT AS A POTENTIAL THERAPEUTIC TARGET IN KIDNEY DISEASES. 2021 18 3762 28 INTEGRATING THE TUMOR-SUPPRESSIVE ACTIVITY OF MASPIN WITH P53 IN RETUNING THE EPITHELIAL HOMEOSTASIS: A WORKING HYPOTHESIS AND APPLICABLE PROSPECTS. EPITHELIAL MALIGNANT TRANSFORMATION AND TUMOROUS DEVELOPMENT WERE BELIEVED TO BE CLOSELY ASSOCIATED WITH THE LOSS OF ITS MICROENVIRONMENT INTEGRITY AND HOMEOSTASIS. THE TUMOR-SUPPRESSIVE MOLECULES MASPIN AND P53 WERE DEMONSTRATED TO PLAY A CRUCIAL ROLE IN BODY EPITHELIAL AND IMMUNE HOMEOSTASIS. DOWNREGULATION OF MASPIN AND MUTATION OF P53 WERE FREQUENTLY ASSOCIATED WITH MALIGNANT TRANSFORMATION AND POOR PROGNOSIS IN VARIOUS HUMAN CANCERS. IN THIS REVIEW, WE FOCUSED ON SUMMARIZING THE PROGRESS OF THE MOLECULAR NETWORK OF MASPIN IN STUDYING EPITHELIAL TUMOROUS DEVELOPMENT AND ITS RESPONSE TO CLINIC TREATMENT AND TRY TO CLARIFY THE UNDERLYING ANTITUMOR MECHANISM. NOTABLY, MASPIN EXPRESSION WAS REPORTED TO BE TRANSCRIPTIONALLY ACTIVATED BY P53, AND THE TRANSCRIPTIONAL ACTIVITY OF P53 WAS DEMONSTRATED TO BE ENHANCED BY ITS ACETYLATION THROUGH INHIBITION OF HDAC1. AS AN ENDOGENOUS INHIBITOR OF HDAC1, MASPIN POSSIBLY POTENTIATES THE TRANSCRIPTIONAL ACTIVITY OF P53 BY ACETYLATING THE P53 PROTEIN. HEREBY, IT COULD FORM A "SELF-PROPELLING" ANTITUMOR MECHANISM. THUS, WE SUMMARIZED THAT, UPON STIMULATION OF CELLULAR STRESS AND BY INTEGRATING WITH P53, THE AROUSED MASPIN PLAYED THE EPIGENETIC SURVEILLANT ROLE TO PREVENT THE EPITHELIAL DIGRESSIONAL PROCESS AND RETUNE THE EPITHELIAL HOMEOSTASIS, WHICH IS INVOLVED IN ACTIVATING HOST IMMUNE SURVEILLANCE, REGULATING THE INFLAMMATORY FACTORS, AND FINE-TUNING ITS ASSOCIATED CELL SIGNALING PATHWAYS. CONSEQUENTIALLY, IN A NORMAL PHYSIOLOGICAL CONDITION, ACTIVATION OF THE ABOVE "SELF-PROPELLING" ANTITUMOR MECHANISM OF MASPIN AND P53 COULD REDUCE CELLULAR STRESS (E.G., CHRONIC INFECTION/INFLAMMATION, OXIDATIVE STRESS, TRANSFORMATION) EFFECTIVELY AND ACHIEVE CANCER PREVENTION. MEANWHILE, DESIGNING A STRATEGY OF MIMICKING MASPIN'S EPIGENETIC REGULATION ACTIVITY WITH INTEGRATING P53 TUMOR-SUPPRESSIVE ACTIVITY COULD ENHANCE THE CHEMOTHERAPY EFFICACY THEORETICALLY IN A PATHOLOGICAL CONDITION OF CANCER. 2022 19 222 22 ACUTE LIVER STEATOSIS TRANSLATIONALLY CONTROLS THE EPIGENETIC REGULATOR MIER1 TO PROMOTE LIVER REGENERATION IN A STUDY WITH MALE MICE. THE EARLY PHASE LIPID ACCUMULATION IS ESSENTIAL FOR LIVER REGENERATION. HOWEVER, WHETHER THIS ACUTE LIPID ACCUMULATION CAN SERVE AS SIGNALS TO DIRECT LIVER REGENERATION RATHER THAN SIMPLY PROVIDING BUILDING BLOCKS FOR CELL PROLIFERATION REMAINS UNCLEAR. THROUGH IN VIVO CRISPR SCREENING, WE IDENTIFY MIER1 (MESODERM INDUCTION EARLY RESPONSE 1) AS A KEY EPIGENETIC REGULATOR THAT BRIDGES THE ACUTE LIPID ACCUMULATION AND CELL CYCLE GENE EXPRESSION DURING LIVER REGENERATION IN MALE ANIMALS. PHYSIOLOGICALLY, LIVER ACUTE LIPID ACCUMULATION INDUCES THE PHOSPHORYLATION OF EIF2S1(EUKARYOTIC TRANSLATION INITIATION FACTOR 2), WHICH CONSEQUENTLY ATTENUATED MIER1 TRANSLATION. MIER1 DOWNREGULATION IN TURN PROMOTES CELL CYCLE GENE EXPRESSION AND REGENERATION THROUGH CHROMATIN REMODELING. IMPORTANTLY, THE LIPIDS-EIF2S1-MIER1 PATHWAY IS IMPAIRED IN ANIMALS WITH CHRONIC LIVER STEATOSIS; WHEREAS MIER1 DEPLETION SIGNIFICANTLY IMPROVES REGENERATION IN THESE ANIMALS. TAKEN TOGETHER, OUR STUDIES IDENTIFY AN EPIGENETIC MECHANISM BY WHICH THE EARLY PHASE LIPID REDISTRIBUTION FROM ADIPOSE TISSUE TO LIVER DURING REGENERATION IMPACTS HEPATOCYTE PROLIFERATION, AND SUGGEST A POTENTIAL STRATEGY TO BOOST LIVER REGENERATION. 2023 20 3468 31 HYPOXIA-INDUCED DNA HYPERMETHYLATION IN HUMAN PULMONARY FIBROBLASTS IS ASSOCIATED WITH THY-1 PROMOTER METHYLATION AND THE DEVELOPMENT OF A PRO-FIBROTIC PHENOTYPE. BACKGROUND: PULMONARY FIBROSIS IS A DEBILITATING AND LETHAL DISEASE WITH NO EFFECTIVE TREATMENT OPTIONS. UNDERSTANDING THE PATHOLOGICAL PROCESSES AT PLAY WILL DIRECT THE APPLICATION OF NOVEL THERAPEUTIC AVENUES. HYPOXIA HAS BEEN IMPLICATED IN THE PATHOGENESIS OF PULMONARY FIBROSIS YET THE PRECISE MECHANISM BY WHICH IT CONTRIBUTES TO DISEASE PROGRESSION REMAINS TO BE FULLY ELUCIDATED. IT HAS BEEN SHOWN THAT CHRONIC HYPOXIA CAN ALTER DNA METHYLATION PATTERNS IN TUMOUR-DERIVED CELL LINES. THIS EPIGENETIC ALTERATION CAN INDUCE CHANGES IN CELLULAR PHENOTYPE WITH PROMOTER METHYLATION BEING ASSOCIATED WITH GENE SILENCING. OF PARTICULAR RELEVANCE TO IDIOPATHIC PULMONARY FIBROSIS (IPF) IS THE OBSERVATION THAT THY-1 PROMOTER METHYLATION IS ASSOCIATED WITH A MYOFIBROBLAST PHENOTYPE WHERE LOSS OF THY-1 OCCURS ALONGSIDE INCREASED ALPHA SMOOTH MUSCLE ACTIN (ALPHA-SMA) EXPRESSION. THE INITIAL AIM OF THIS STUDY WAS TO DETERMINE WHETHER HYPOXIA REGULATES DNA METHYLATION IN NORMAL HUMAN LUNG FIBROBLASTS (CCD19LU). AS IT HAS BEEN REPORTED THAT HYPOXIA SUPPRESSES THY-1 EXPRESSION DURING LUNG DEVELOPMENT WE ALSO STUDIED THE EFFECT OF HYPOXIA ON THY-1 PROMOTER METHYLATION AND GENE EXPRESSION. METHODS: CCD19LU WERE GROWN FOR UP TO 8 DAYS IN HYPOXIA AND ASSESSED FOR GLOBAL CHANGES IN DNA METHYLATION USING FLOW CYTOMETRY. REAL-TIME PCR WAS USED TO QUANTIFY EXPRESSION OF THY-1, ALPHA-SMA, COLLAGEN I AND III. GENOMIC DNA WAS BISULPHITE TREATED AND METHYLATION SPECIFIC PCR (MSPCR) WAS USED TO EXAMINE THE METHYLATION STATUS OF THE THY-1 PROMOTER. RESULTS: SIGNIFICANT GLOBAL HYPERMETHYLATION WAS DETECTED IN HYPOXIC FIBROBLASTS RELATIVE TO NORMOXIC CONTROLS AND WAS ACCOMPANIED BY INCREASED EXPRESSION OF MYOFIBROBLAST MARKERS. THY-1 MRNA EXPRESSION WAS SUPPRESSED IN HYPOXIC CELLS, WHICH WAS RESTORED WITH THE DEMETHYLATING AGENT 5-AZA-2'-DEOXYCYTIDINE. MSPCR REVEALED THAT THY-1 BECAME METHYLATED FOLLOWING FIBROBLAST EXPOSURE TO 1% O2. CONCLUSION: THESE DATA SUGGEST THAT GLOBAL AND GENE-SPECIFIC CHANGES IN DNA METHYLATION MAY PLAY AN IMPORTANT ROLE IN FIBROBLAST FUNCTION IN HYPOXIA. 2012