1 3809 161 INTRAPERITONEAL 5-AZACYTIDINE ALLEVIATES NERVE INJURY-INDUCED PAIN IN RATS BY MODULATING DNA METHYLATION. TO INVESTIGATE THE ROLE OF DNA METHYLATION IN MODULATING CHRONIC NEUROPATHIC PAIN (NPP), IDENTIFY POSSIBLE TARGET GENES OF DNA METHYLATION INVOLVED IN THIS PROCESS, AND PRELIMINARILY CONFIRM THE MEDICINAL VALUE OF THE DNA METHYLTRANSFERASES (DNMTS) INHIBITOR 5-AZACYTIDINE (5-AZA) IN NPP BY TARGETING GENE METHYLATION. TWO RAT NPP MODELS, CHRONIC CONSTRICTION INJURY (CCI) AND SPINAL NERVE LIGATION (SNL), WERE USED. THE DNA METHYLATION PROFILES IN THE LUMBAR SPINAL CORD WERE ASSAYED USING AN ARRAYSTAR RAT REFSEQ PROMOTER ARRAY. THE UNDERLYING GENES WITH DIFFERENTIAL METHYLATION WERE THEN IDENTIFIED AND SUBMITTED TO GENE ONTOLOGY AND PATHWAY ANALYSIS. METHYL-DNA IMMUNOPRECIPITATION QUANTITATIVE PCR (MEDIP-QPCR) AND QUANTITATIVE REVERSE TRANSCRIPTION-PCR (RT-QPCR) WERE USED TO CONFIRM GENE METHYLATION AND EXPRESSION. THE PROTECTIVE FUNCTION OF 5-AZA IN NPP AND GENE EXPRESSION WERE EVALUATED VIA BEHAVIORAL ASSAYS AND RT-QPCR, RESPECTIVELY. ANALYSIS OF THE DNA METHYLATION PATTERNS IN THE LUMBAR SPINAL CORD INDICATED THAT 1205 DIFFERENTIALLY METHYLATED FRAGMENTS IN CCI RATS WERE LOCATED WITHIN DNA PROMOTER REGIONS, INCLUDING 638 HYPERMETHYLATED FRAGMENTS AND 567 HYPOMETHYLATED FRAGMENTS. THE METHYLATION LEVELS OF GRM4, HTR4, ADRB2, KCNF1, GAD2, AND PPARG, WHICH ARE ASSOCIATED WITH LONG-TERM POTENTIATION (LTP) AND GLUTAMATERGIC SYNAPSE PATHWAYS, WERE INCREASED WITH A CORRESPONDING DECREASE IN THEIR MRNA EXPRESSION, IN THE SPINAL CORDS OF CCI RATS. MOREOVER, WE FOUND THAT THE INTRAPERITONEAL INJECTION OF 5-AZA (4 MG/KG) ATTENUATED CCI- OR SNL-INDUCED MECHANICAL ALLODYNIA AND THERMAL HYPERALGESIA. FINALLY, THE MRNA EXPRESSION OF HYPERMETHYLATED GENES SUCH AS GRM4, HTR4, ADRB2, KCNF1, AND GAD2 WAS REVERSED AFTER 5-AZA TREATMENT. CCI INDUCED WIDESPREAD METHYLATION CHANGES IN THE DNA PROMOTER REGIONS IN THE LUMBAR SPINAL CORD. INTRAPERITONEAL 5-AZA ALLEVIATED HYPERALGESIA IN CCI AND SNL RATS, AN EFFECT ACCOMPANIED BY THE REVERSED EXPRESSION OF HYPERMETHYLATED GENES. THUS, DNA METHYLATION INHIBITION REPRESENTS A PROMISING EPIGENETIC STRATEGY FOR PROTECTION AGAINST CHRONIC NPP FOLLOWING NERVE INJURY. OUR STUDY LAYS A THEORETICAL FOUNDATION FOR 5-AZA TO BECOME A CLINICAL TARGETED DRUG. 2023 2 1154 30 CONSERVED DNA METHYLATION PATTERNS IN HEALTHY BLOOD CELLS AND EXTENSIVE CHANGES IN LEUKEMIA MEASURED BY A NEW QUANTITATIVE TECHNIQUE. GENOME WIDE ANALYSIS OF DNA METHYLATION PROVIDES IMPORTANT INFORMATION IN A VARIETY OF DISEASES, INCLUDING CANCER. HERE, WE DESCRIBE A SIMPLE METHOD, DIGITAL RESTRICTION ENZYME ANALYSIS OF METHYLATION (DREAM), BASED ON NEXT GENERATION SEQUENCING ANALYSIS OF METHYLATION-SPECIFIC SIGNATURES CREATED BY SEQUENTIAL DIGESTION OF GENOMIC DNA WITH SMAI AND XMAI ENZYMES. DREAM PROVIDES INFORMATION ON 150,000 UNIQUE CPG SITES, OF WHICH 39,000 ARE IN CPG ISLANDS AND 30,000 ARE AT TRANSCRIPTION START SITES OF 13,000 REFSEQ GENES. WE ANALYZED DNA METHYLATION IN HEALTHY WHITE BLOOD CELLS AND FOUND METHYLATION PATTERNS TO BE REMARKABLY UNIFORM. INTER INDIVIDUAL DIFFERENCES > 30% WERE OBSERVED ONLY AT 227 OF 28,331 (0.8%) OF AUTOSOMAL CPG SITES. SIMILARLY, > 30% DIFFERENCES WERE OBSERVED AT ONLY 59 SITES WHEN WE COMPARING THE CORD AND ADULT BLOOD. THESE CONSERVED METHYLATION PATTERNS CONTRASTED WITH EXTENSIVE CHANGES AFFECTING 18-40% OF CPG SITES IN A PATIENT WITH ACUTE MYELOID LEUKEMIA AND IN TWO LEUKEMIA CELL LINES. THE METHOD IS COST EFFECTIVE, QUANTITATIVE (R ( 2) = 0.93 WHEN COMPARED WITH BISULFITE PYROSEQUENCING) AND REPRODUCIBLE (R ( 2) = 0.997). USING 100-FOLD COVERAGE, DREAM CAN DETECT DIFFERENCES IN METHYLATION GREATER THAN 10% OR 30% WITH A FALSE POSITIVE RATE BELOW 0.05 OR 0.001, RESPECTIVELY. DREAM CAN BE USEFUL IN QUANTIFYING EPIGENETIC EFFECTS OF ENVIRONMENT AND NUTRITION, CORRELATING DEVELOPMENTAL EPIGENETIC VARIATION WITH PHENOTYPES, UNDERSTANDING EPIGENETICS OF CANCER AND CHRONIC DISEASES, MEASURING THE EFFECTS OF DRUGS ON DNA METHYLATION OR DERIVING NEW BIOLOGICAL INSIGHTS INTO MAMMALIAN GENOMES. 2012 3 101 42 A RAT METHYL-SEQ PLATFORM TO IDENTIFY EPIGENETIC CHANGES ASSOCIATED WITH STRESS EXPOSURE. AS GENOMES OF A WIDER VARIETY OF ANIMALS BECOME AVAILABLE, THERE IS AN INCREASING NEED FOR TOOLS THAT CAN CAPTURE DYNAMIC EPIGENETIC CHANGES IN THESE ANIMAL MODELS. THE RAT IS ONE PARTICULAR MODEL ANIMAL WHERE AN EPIGENETIC TOOL CAN COMPLEMENT MANY PHARMACOLOGICAL AND BEHAVIORAL STUDIES TO PROVIDE INSIGHTFUL MECHANISTIC INFORMATION. TO THIS END, WE ADAPTED THE SURESELECT TARGET CAPTURE SYSTEM (REFERRED TO AS METHYL-SEQ) FOR THE RAT, WHICH CAN ASSESS DNA METHYLATION LEVELS ACROSS THE RAT GENOME. THE RAT DESIGN TARGETED PROMOTERS, CPG ISLANDS, ISLAND SHORES, AND GC-RICH REGIONS FROM ALL REFSEQ GENES. TO IMPLEMENT THE PLATFORM ON A RAT EXPERIMENT, MALE SPRAGUE DAWLEY RATS WERE EXPOSED TO CHRONIC VARIABLE STRESS FOR 3 WEEKS, AFTER WHICH BLOOD SAMPLES WERE COLLECTED FOR GENOMIC DNA EXTRACTION. METHYL-SEQ LIBRARIES WERE CONSTRUCTED FROM THE RAT DNA SAMPLES BY SHEARING, ADAPTER LIGATION, TARGET ENRICHMENT, BISULFITE CONVERSION, AND MULTIPLEXING. LIBRARIES WERE SEQUENCED ON A NEXT-GENERATION SEQUENCING PLATFORM AND THE SEQUENCED READS WERE ANALYZED TO IDENTIFY DMRS BETWEEN DNA OF STRESSED AND UNSTRESSED RATS. TOP CANDIDATE DMRS WERE INDEPENDENTLY VALIDATED BY BISULFITE PYROSEQUENCING TO CONFIRM THE ROBUSTNESS OF THE PLATFORM. RESULTS DEMONSTRATE THAT THE RAT METHYL-SEQ PLATFORM IS A USEFUL EPIGENETIC TOOL THAT CAN CAPTURE METHYLATION CHANGES INDUCED BY EXPOSURE TO STRESS. 2018 4 6752 38 WIDESPREAD EXONIZATION OF TRANSPOSABLE ELEMENTS IN HUMAN CODING SEQUENCES IS ASSOCIATED WITH EPIGENETIC REGULATION OF TRANSCRIPTION. TRANSPOSABLE ELEMENTS (TES) HAVE LONG BEEN REGARDED AS SELFISH OR JUNK DNA HAVING LITTLE OR NO ROLE IN THE REGULATION OR FUNCTIONING OF THE HUMAN GENOME. HOWEVER, OVER THE PAST SEVERAL YEARS THIS VIEW CAME TO BE CHALLENGED AS SEVERAL STUDIES PROVIDED ANECDOTAL AS WELL AS GLOBAL EVIDENCE FOR THE CONTRIBUTION OF TES TO THE REGULATORY AND CODING NEEDS OF HUMAN GENES. IN THIS STUDY, WE EXPLORED THE INCORPORATION AND EPIGENETIC REGULATION OF CODING SEQUENCES DONATED BY TES USING GENE EXPRESSION AND OTHER ANCILLARY GENOMICS DATA FROM TWO HUMAN HEMATOPOIETIC CELL-LINES: GM12878 (A LYMPHOBLASTOID CELL LINE) AND K562 (A CHRONIC MYELOGENOUS LEUKEMIA CELL LINE). IN EACH CELL LINE, WE FOUND SEVERAL THOUSAND INSTANCES OF TES DONATING CODING SEQUENCES TO HUMAN GENES. WE COMPARED THE TRANSCRIPTOME ASSEMBLY OF THE RNA SEQUENCING (RNA-SEQ) READS WITH AND WITHOUT THE AID OF A REFERENCE TRANSCRIPTOME AND FOUND THAT THE PERCENTAGE OF GENES THAT INCORPORATE TES IN THEIR CODING SEQUENCES IS SIGNIFICANTLY GREATER THAN THAT OBTAINED FROM THE REFERENCE TRANSCRIPTOME ASSEMBLIES USING REFSEQ AND GENCODE GENE MODELS. WE ALSO USED HISTONE MODIFICATIONS CHROMATIN IMMUNOPRECIPITATION SEQUENCING (CHIP-SEQ) DATA, CAP ANALYSIS OF GENE EXPRESSION (CAGE) DATA AND DNASEI HYPERSENSITIVITY SITE (DHS) DATA TO DEMONSTRATE THE EPIGENETIC REGULATION OF THE TE DERIVED CODING SEQUENCES. OUR RESULTS SUGGEST THAT TES FORM A SIGNIFICANTLY HIGHER PERCENTAGE OF CODING SEQUENCES THAN REPRESENTED IN GENE ANNOTATION DATABASES AND THESE TE DERIVED SEQUENCES ARE EPIGENETICALLY REGULATED IN ACCORDANCE WITH THEIR EXPRESSION IN THE TWO CELL TYPES. 2013 5 1132 44 COMPREHENSIVE DNA METHYLATION ANALYSIS USING A METHYL-CPG-BINDING DOMAIN CAPTURE-BASED METHOD IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS. THE ROLE OF LONG NONCODING RNAS (LNCRNAS) IN CANCER IS COMING TO THE FOREFRONT DUE TO GROWING INTEREST IN UNDERSTANDING THEIR MECHANISTIC FUNCTIONS DURING CANCER DEVELOPMENT AND PROGRESSION. DESPITE THIS, THE GLOBAL EPIGENETIC REGULATION OF LNCRNAS AND REPETITIVE SEQUENCES IN CANCER HAS NOT BEEN WELL INVESTIGATED, PARTICULARLY IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). THIS STUDY FOCUSES ON A UNIQUE APPROACH: THE IMMUNOPRECIPITATION-BASED CAPTURE OF DOUBLE-STRANDED, METHYLATED DNA FRAGMENTS USING METHYL-BINDING DOMAIN (MBD) PROTEINS, FOLLOWED BY NEXT-GENERATION SEQUENCING (MBD-SEQ). CLL PATIENT SAMPLES BELONGING TO TWO PROGNOSTIC SUBGROUPS (5 IGVH MUTATED SAMPLES + 5 IGVH UNMUTATED SAMPLES) WERE USED IN THIS STUDY. ANALYSIS REVEALED 5,800 HYPERMETHYLATED AND 12,570 HYPOMETHYLATED CLL-SPECIFIC DIFFERENTIALLY METHYLATED GENES (CLLDMGS) COMPARED TO NORMAL HEALTHY CONTROLS. IMPORTANTLY, THESE RESULTS IDENTIFIED SEVERAL CLL-SPECIFIC, DIFFERENTIALLY METHYLATED LNCRNAS, REPETITIVE ELEMENTS, AND PROTEIN-CODING GENES WITH POTENTIAL PROGNOSTIC VALUE. THIS WORK OUTLINES A DETAILED PROTOCOL FOR AN MBD-SEQ AND BIOINFORMATICS PIPELINE DEVELOPED FOR THE COMPREHENSIVE ANALYSIS OF GLOBAL METHYLATION PROFILES IN HIGHLY CPG-RICH REGIONS USING CLL PATIENT SAMPLES. FINALLY, A PROTEIN-CODING GENE AND AN LNCRNA WERE VALIDATED USING PYROSEQUENCING, WHICH IS A HIGHLY QUANTITATIVE METHOD TO ANALYZE CPG METHYLATION LEVELS TO FURTHER CORROBORATE THE FINDINGS FROM THE MBD-SEQ PROTOCOL. 2017 6 6613 31 ULTRADEEP BISULFITE SEQUENCING ANALYSIS OF DNA METHYLATION PATTERNS IN MULTIPLE GENE PROMOTERS BY 454 SEQUENCING. WE DEVELOPED A NOVEL APPROACH FOR CONDUCTING MULTISAMPLE, MULTIGENE, ULTRADEEP BISULFITE SEQUENCING ANALYSIS OF DNA METHYLATION PATTERNS IN CLINICAL SAMPLES. A MASSIVELY PARALLEL SEQUENCING-BY-SYNTHESIS METHOD (454 SEQUENCING) WAS USED TO DIRECTLY SEQUENCE >100 BISULFITE PCR PRODUCTS IN A SINGLE SEQUENCING RUN WITHOUT SUBCLONING. WE SHOWED THE UTILITY, ROBUSTNESS, AND SUPERIORITY OF THIS APPROACH BY ANALYZING METHYLATION IN 25 GENE-RELATED CPG RICH REGIONS FROM >40 CASES OF PRIMARY CELLS, INCLUDING NORMAL PERIPHERAL BLOOD LYMPHOCYTES, ACUTE LYMPHOBLASTIC LEUKEMIA (ALL), CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), FOLLICULAR LYMPHOMA (FL), AND MANTLE CELL LYMPHOMA (MCL). A TOTAL OF 294,631 SEQUENCES WAS GENERATED WITH AN AVERAGE READ LENGTH OF 131 BP. ON AVERAGE, >1,600 INDIVIDUAL SEQUENCES WERE GENERATED FOR EACH PCR AMPLICON FAR BEYOND THE FEW CLONES (<20) TYPICALLY ANALYZED BY TRADITIONAL BISULFITE SEQUENCING. COMPREHENSIVE ANALYSIS OF CPG METHYLATION PATTERNS AT A SINGLE DNA MOLECULE LEVEL USING CLUSTERING ALGORITHMS REVEALED DIFFERENTIAL METHYLATION PATTERNS BETWEEN DISEASES. A SIGNIFICANT INCREASE IN METHYLATION WAS DETECTED IN ALL AND FL SAMPLES COMPARED WITH CLL AND MCL. FURTHERMORE, A PROGRESSIVE SPREADING OF METHYLATION WAS DETECTED FROM THE PERIPHERY TOWARD THE CENTER OF SELECT CPG ISLANDS IN THE ALL AND FL SAMPLES. THE ULTRADEEP SEQUENCING ALSO ALLOWED SIMULTANEOUS ANALYSIS OF GENETIC AND EPIGENETIC DATA AND REVEALED AN ASSOCIATION BETWEEN A SINGLE NUCLEOTIDE POLYMORPHISM AND THE METHYLATION PRESENT IN THE LRP1B PROMOTER. THIS NEW GENERATION OF METHYLOME SEQUENCING WILL PROVIDE DIGITAL PROFILES OF ABERRANT DNA METHYLATION FOR INDIVIDUAL HUMAN CANCERS AND OFFERS A ROBUST METHOD FOR THE EPIGENETIC CLASSIFICATION OF TUMOR SUBTYPES. 2007 7 3138 45 GLOBAL DNA METHYLATION PROFILING REVEALS NEW INSIGHTS INTO EPIGENETICALLY DEREGULATED PROTEIN CODING AND LONG NONCODING RNAS IN CLL. BACKGROUND: METHYL-CPG-BINDING DOMAIN PROTEIN ENRICHED GENOME-WIDE SEQUENCING (MBD-SEQ) IS A ROBUST AND POWERFUL METHOD FOR ANALYZING METHYLATED CPG-RICH REGIONS WITH COMPLETE GENOME-WIDE COVERAGE. IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), THE ROLE OF CPG METHYLATED REGIONS ASSOCIATED WITH TRANSCRIBED LONG NONCODING RNAS (LNCRNA) AND REPETITIVE GENOMIC ELEMENTS ARE POORLY UNDERSTOOD. BASED ON MBD-SEQ, WE CHARACTERIZED THE GLOBAL METHYLATION PROFILE OF HIGH CPG-RICH REGIONS IN DIFFERENT CLL PROGNOSTIC SUBGROUPS BASED ON IGHV MUTATIONAL STATUS. RESULTS: OUR STUDY IDENTIFIED 5800 HYPERMETHYLATED AND 12,570 HYPOMETHYLATED CLL-SPECIFIC DIFFERENTIALLY METHYLATED GENES (CLLDMGS) COMPARED TO NORMAL CONTROLS. FROM CLLDMGS, 40 % OF HYPERMETHYLATED AND 60 % OF HYPOMETHYLATED GENES WERE MAPPED TO NONCODING RNAS. IN ADDITION, WE FOUND THAT THE MAJOR REPETITIVE ELEMENTS SUCH AS SHORT INTERSPERSED ELEMENTS (SINE) AND LONG INTERSPERSED ELEMENTS (LINE) HAVE A HIGH PERCENTAGE OF CLLDMRS (DIFFERENTIALLY METHYLATED REGIONS) IN IGHV SUBGROUPS COMPARED TO NORMAL CONTROLS. FINALLY, TWO NOVEL LNCRNAS (HYPERMETHYLATED CRNDE AND HYPOMETHYLATED AC012065.7) WERE VALIDATED IN AN INDEPENDENT CLL SAMPLE COHORT (48 SAMPLES) COMPARED WITH 6 NORMAL SORTED B CELL SAMPLES USING QUANTITATIVE PYROSEQUENCING ANALYSIS. THE METHYLATION LEVELS SHOWED AN INVERSE CORRELATION TO GENE EXPRESSION LEVELS ANALYZED BY REAL-TIME QUANTITATIVE PCR. NOTABLY, SURVIVAL ANALYSIS REVEALED THAT HYPERMETHYLATION OF CRNDE AND HYPOMETHYLATION OF AC012065.7 CORRELATED WITH AN INFERIOR OUTCOME. CONCLUSIONS: THUS, OUR COMPREHENSIVE METHYLATION ANALYSIS BY MBD-SEQ PROVIDED NOVEL HYPER AND HYPOMETHYLATED LONG NONCODING RNAS, REPETITIVE ELEMENTS, ALONG WITH PROTEIN CODING GENES AS POTENTIAL EPIGENETIC-BASED CLL-SIGNATURE GENES INVOLVED IN DISEASE PATHOGENESIS AND PROGNOSIS. 2016 8 1869 26 EMERGING ROLE OF DREAM IN HEALTHY BRAIN AND NEUROLOGICAL DISEASES. THE DOWNSTREAM REGULATORY ELEMENT ANTAGONIST MODULATOR (DREAM) IS A MULTIFUNCTIONAL CA(2+)-SENSITIVE PROTEIN EXERTING A DUAL MECHANISM OF ACTION TO REGULATE SEVERAL CA(2+)-DEPENDENT PROCESSES. UPON SUMOYLATION, DREAM ENTERS IN NUCLEUS WHERE IT DOWNREGULATES THE EXPRESSION OF SEVERAL GENES PROVIDED WITH A CONSENSUS SEQUENCE NAMED DREAM REGULATORY ELEMENT (DRE). ON THE OTHER HAND, DREAM COULD ALSO DIRECTLY MODULATE THE ACTIVITY OR THE LOCALIZATION OF SEVERAL CYTOSOLIC AND PLASMA MEMBRANE PROTEINS. IN THIS REVIEW, WE SUMMARIZE RECENT ADVANCES IN THE KNOWLEDGE OF DREAM DYSREGULATION AND DREAM-DEPENDENT EPIGENETIC REMODELING AS A CENTRAL MECHANISM IN THE PROGRESSION OF SEVERAL DISEASES AFFECTING CENTRAL NERVOUS SYSTEM, INCLUDING STROKE, ALZHEIMER'S AND HUNTINGTON'S DISEASES, AMYOTROPHIC LATERAL SCLEROSIS, AND NEUROPATHIC PAIN. INTERESTINGLY, DREAM SEEMS TO EXERT A COMMON DETRIMENTAL ROLE IN THESE DISEASES BY INHIBITING THE TRANSCRIPTION OF SEVERAL NEUROPROTECTIVE GENES, INCLUDING THE SODIUM/CALCIUM EXCHANGER ISOFORM 3 (NCX3), BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF), PRO-DYNORPHIN, AND C-FOS. THESE FINDINGS LEAD TO THE CONCEPT THAT DREAM MIGHT REPRESENT A PHARMACOLOGICAL TARGET TO AMELIORATE SYMPTOMS AND REDUCE NEURODEGENERATIVE PROCESSES IN SEVERAL PATHOLOGICAL CONDITIONS AFFECTING CENTRAL NERVOUS SYSTEM. 2023 9 4579 32 N(6)-METHYLADENOSINE METHYLASE METTL3 CONTRIBUTES TO NEUROPATHIC PAIN BY EPIGENETIC SILENCING OF MU OPIOID RECEPTOR. WE AIMED AT EXPLORING THE ROLE AND MECHANISM OF METTL3-MEDIATED M(6)A MODIFICATION IN NEUROPATHIC PAIN. MALE SPRAGUE-DAWLEY RATS WERE RANDOMLY DIVIDED INTO FOUR GROUPS: SHAM OPERATION GROUP (SHAM GROUP), CHRONIC CONSTRICTION INJURY (CCI) OF THE SCIATIC NERVE MODEL GROUP (NPP GROUP), INTRATHECAL INJECTION OF VIRUS DOWN-REGULATED METTL3 + CCI MODEL GROUP (M3 + NPP GROUP) AND INTRATHECAL INJECTION OF NEGATIVE CONTROL VIRUS + CCI MODEL GROUP (SCR + NPP GROUP). THE M3 + NPP GROUP AND THE SCR + NPP GROUP WERE INTRATHECALLY INJECTED WITH VIRUS NINETEEN DAYS BEFORE OPERATION. THE PAW WITHDRAWAL MECHANICAL THRESHOLDS AND PAW WITHDRAWAL LATENCY WERE RESPECTIVELY RECORDED ONE DAY BEFORE OPERATION, THREE DAYS, FIVE DAYS AND SEVEN DAYS AFTER OPERATION. THE RATS WERE SACRIFICED ON THE SEVENTH DAY AFTER OPERATION, AND THEIR SPINAL CORD TISSUES WERE TAKEN. THE FROZEN SECTIONS OF RATS WERE PERFORMED TO OBSERVE THE EXPRESSION OF GREEN FLUORESCENT PROTEIN OF THE VIRUS. THE METHYLATION LEVEL OF RNA, THE PROTEIN EXPRESSION OF M(6)A-RELATED ENZYME (METTL3) AND MU OPIOID RECEPTOR (MOR) IN SPINAL CORD TISSUES OF THE FOUR GROUPS WERE MEASURED. DOWNREGULATION OF METTL3 HAD NO EFFECT ON THE OVERALL METHYLATION LEVEL OF THE SPINAL CORD, BUT IT COULD REGULATE THE METHYLATION LEVEL OF THE OPRM1 GENE RNA ENCODING MOR, PARTIALLY RESTORE THE EXPRESSION OF MOR, AND RELIEVE PAIN IN RATS. IN THE PROCESS OF NPP, METTL3 MAY INHIBIT THE EXPRESSION OF MOR BY REGULATING THE METHYLATION LEVEL OF OPRM1 GENE RNA ENCODING MOR, AND ULTIMATELY PROMOTE THE OCCURRENCE AND DEVELOPMENT OF NPP. 2023 10 1620 42 DNA METHYLTRANSFERASE-MEDIATED TRANSCRIPTIONAL SILENCING IN MALIGNANT GLIOMA: A COMBINED WHOLE-GENOME MICROARRAY AND PROMOTER ARRAY ANALYSIS. EPIGENETIC INACTIVATION OF TUMOR SUPPRESSOR GENES IS A COMMON FEATURE IN HUMAN CANCER. PROMOTER HYPERMETHYLATION AND HISTONE DEACETYLATION ARE REVERSIBLE EPIGENETIC MECHANISMS ASSOCIATED WITH TRANSCRIPTIONAL REGULATION. DNA METHYLTRANSFERASES (DNMT1 AND DNMT3B) REGULATE AND MAINTAIN PROMOTER METHYLATION AND ARE OVEREXPRESSED IN HUMAN CANCER. WE PERFORMED WHOLE-GENOME MICROARRAY ANALYSIS TO IDENTIFY GENES WITH ALTERED EXPRESSION AFTER RNAI-INDUCED SUPPRESSION OF DNMT IN A GLIOBLASTOMA MULTIFORME (GBM) CELL LINE. WE THEN IDENTIFIED GENES WITH BOTH DECREASED EXPRESSION AND EVIDENCE OF PROMOTER CPG ISLAND HYPERMETHYLATION IN GBM TISSUE SAMPLES USING A COMBINED WHOLE-GENOME MICROARRAY TRANSCRIPTOME ANALYSIS IN CONJUNCTION WITH A PROMOTER ARRAY ANALYSIS AFTER DNA IMMUNOPRECIPITATION WITH ANTI-5-METHYLCYTIDINE. DNMT1 AND 3B KNOCKDOWN RESULTED IN THE RESTORED EXPRESSION OF 308 GENES THAT ALSO CONTAINED PROMOTER REGION HYPERMETHYLATION. OF THESE, 43 WERE ALSO FOUND TO BE DOWNREGULATED IN GBM TISSUE SAMPLES. THREE DOWNREGULATED GENES WITH HYPERMETHYLATED PROMOTERS AND RESTORED EXPRESSION IN RESPONSE TO ACUTE DNMT SUPPRESSION WERE ASSAYED FOR METHYLATION CHANGES USING BISULFITE SEQUENCE ANALYSIS OF THE PROMOTER REGION AFTER CHRONIC DNMT SUPPRESSION. RESTORATION OF GENE EXPRESSION WAS NOT ASSOCIATED WITH CHANGES IN PROMOTER REGION METHYLATION, BUT RATHER WITH CHANGES IN HISTONE METHYLATION AND CHROMATIN CONFORMATION. TWO OF THE IDENTIFIED GENES EXHIBITED GROWTH SUPPRESSIVE ACTIVITY IN IN VITRO ASSAYS. COMBINING TARGETED GENETIC MANIPULATIONS WITH COMPREHENSIVE GENOMIC AND EXPRESSION ANALYSES PROVIDES A POTENTIALLY POWERFUL NEW APPROACH FOR IDENTIFYING EPIGENETICALLY REGULATED GENES IN GBM. 2009 11 3460 32 HYPOMETHYLATION OF THE IL8 PROMOTER IN NASAL EPITHELIAL CELLS OF PATIENTS WITH CHRONIC RHINOSINUSITIS WITH NASAL POLYPS. BACKGROUND: IL-8 IS AN IMPORTANT CHEMOKINE IMPLICATED IN THE PATHOGENESIS OF CHRONIC RHINOSINUSITIS (CRS), BUT LITTLE IS KNOWN ABOUT EPIGENETIC REGULATION OF IL8 IN THE PATHOGENESIS OF CRS. OBJECTIVE: WE SOUGHT TO INVESTIGATE THE RELATIONSHIP BETWEEN THE DNA METHYLATION LEVEL IN THE IL8 PROXIMAL PROMOTER AND CRS IN HAN CHINESE SUBJECTS. METHODS: PATIENTS WITH CHRONIC RHINOSINUSITIS WITH NASAL POLYPS (CRSWNP; N = 187), PATIENTS WITH CHRONIC RHINOSINUSITIS WITHOUT NASAL POLYPS (CRSSNP; N = 89), AND CONTROL SUBJECTS (N = 57) WERE ENROLLED IN 2 INDEPENDENT COHORTS. PURIFIED HUMAN NASAL EPITHELIAL CELLS FROM EACH PARTICIPANT WERE ASSESSED FOR PERCENTAGE DNA METHYLATION OF CPG SITES IN THE IL8 PROXIMAL PROMOTER BY USING BISULFITE PYROSEQUENCING AND FOR FUNCTIONAL ASPECTS OF METHYLATION STATUS BY USING IN VITRO ASSAYS. RESULTS: DNA METHYLATION OF CPG SITES 1, 2, AND 3, RESPECTIVELY, IN THE IL8 PROXIMAL PROMOTER WAS SIGNIFICANTLY DECREASED IN HUMAN NASAL EPITHELIAL CELLS OF PATIENTS WITH CRSWNP COMPARED WITH THAT IN PATIENTS WITH CRSSNP (P < .001) AND CONTROL SUBJECTS (P < .001). PERCENTAGE OF DNA METHYLATION OF THE CPG3 SITE WAS CORRELATED NEGATIVELY WITH BOTH TISSUE EOSINOPHILIC CATIONIC PROTEIN (P < .01) AND MYELOPEROXIDASE (P < .05) LEVELS. IL-1BETA (P < .001) AND TNF-ALPHA (P < .01) SIGNIFICANTLY INCREASED IL8 EXPRESSION ACCOMPANIED BY A REDUCTION IN METHYLATION AT THE CPG3 SITE (P < .001). ELECTROPHORETIC MOBILITY SHIFT ASSAYS DEMONSTRATED THAT METHYLATION STATUS OF CPG3 CHANGED THE BINDING OF OCTAMER-BINDING TRANSCRIPTION FACTOR 1 AND NUCLEAR FACTOR KAPPAB. CONCLUSION: DECREASED DNA METHYLATION OF PARTICULARLY CPG SITES IN THE IL8 PROXIMAL PROMOTER MIGHT PLAY A ROLE IN THE PATHOGENESIS OF CRSWNP. 2019 12 2261 25 EPIGENETIC PROFILE IN CHRONIC LYMPHOCYTIC LEUKEMIA USING METHYLATION-SPECIFIC MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION. AIM: TO ANALYZE THE METHYLATION STATUS OF 35 TUMOR SUPPRESSOR GENES USING METHYLATION-SPECIFIC MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION (MS-MLPA) IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). MATERIALS & METHODS: THE DNA OF 37 SAMPLES FROM PATIENTS WITH CLL, SIX HEALTHY DONORS, AND JURKAT AND RAMOS CELL LINES WAS ANALYZED BY MS-MLPA. RESULTS: OUR RESULTS CONFIRM THAT HYPERMETHYLATION IS A COMMON AND NOT RANDOMLY DISTRIBUTED EVENT IN CLL, AND SOME GENES, SUCH AS WT1, CDH13, IGSF4/TSLC1, GATA5, DAPK1 AND RARB, ARE HYPERMETHYLATED IN MORE THAN 25% OF THE ANALYZED SAMPLES. IMPORTANTLY, MS-MLPA ALSO DETECTED HYPERMETHYLATION OF SOME GENES NOT REPORTED PREVIOUSLY IN CLL, AND THEIR METHYLATION STATUS WAS CONFIRMED BY BISULFITE SEQUENCING. CONCLUSION: THESE RESULTS INDICATE THAT MS-MLPA IS A USEFUL TECHNIQUE FOR THE DETECTION OF METHYLATION IN CLL SAMPLES. SELECTING CLL-SPECIFIC METHYLATION TARGETS IN ORDER TO GENERATE A CLL-SPECIFIC MS-MLPA PROBE SET COULD ENHANCE ITS USEFULNESS AS A TOOL IN STUDIES OF RISK STRATIFICATION AND GUIDING THE BEST THERAPEUTIC DECISION. 2012 13 5823 34 STRESS INCREASES DNA METHYLATION OF THE NEURONAL PAS DOMAIN 4 (NPAS4) GENE. NEURONAL PER ARNT SIM DOMAIN 4 (NPAS4), A BRAIN-SPECIFIC HELIX-LOOP-HELIX TRANSCRIPTION FACTOR, WAS RECENTLY SHOWN TO REGULATE THE DEVELOPMENT OF GABAERGIC INHIBITORY NEURONS. NPAS4 MRNA EXPRESSION LEVELS WERE DECREASED IN THE HIPPOCAMPUS OF MICE EXPOSED TO STRESS, WHICH WAS ACCOMPANIED BY BRAIN DYSFUNCTION. WE HAVE SUGGESTED THAT TRANSIENT STRESS REDUCED NPAS4 TRANSCRIPTION THROUGH THE GLUCOCORTICOID RECEPTOR. IN THE PRESENT REPORT, WE INVESTIGATED THE POTENTIAL CONTRIBUTION OF EPIGENETIC MODIFICATIONS INDUCED BY STRESS ON NPAS4 GENE EXPRESSION. THE NPAS4 PROMOTER REGION CONTAINS TWO CPG ISLANDS; IN THE HIPPOCAMPUS, CHRONIC RESTRAINT STRESS INCREASES THE DNA METHYLATION LEVELS OF BOTH OF THESE CPG ISLANDS. IN THE NEURO2A CELL LINE, TREATMENT WITH A DNA METHYLTRANSFERASE INHIBITOR, 5-AZA-2'-DEOXYCYTIDINE, INCREASED NPAS4 MRNA LEVELS AND MARKEDLY REDUCED THE DNA METHYLATION LEVELS OF CPG ISLAND 2 IN THE NPAS4 PROMOTER. THE DNA METHYLATION SITES IN CPG ISLAND 2 OVERLAP WITH TWO CYCLIC ADENOSINE MONOPHOSPHATE RESPONSE ELEMENT (CRE) SEQUENCES. MUTATION OF THESE CRE SEQUENCES REDUCED NPAS4 PROMOTER ACTIVITY. THESE RESULTS SUGGEST THAT TRANSCRIPTION OF THE NPAS4 GENE IS DOWNREGULATED BY STRESS THROUGH DNA METHYLATION OF ITS PROMOTER. 2015 14 4617 51 NERVE INJURY-INDUCED CHRONIC PAIN IS ASSOCIATED WITH PERSISTENT DNA METHYLATION REPROGRAMMING IN DORSAL ROOT GANGLION. NERVE INJURY-INDUCED HYPERACTIVITY OF PRIMARY SENSORY NEURONS IN THE DORSAL ROOT GANGLION (DRG) CONTRIBUTES TO CHRONIC PAIN DEVELOPMENT, BUT THE UNDERLYING EPIGENETIC MECHANISMS REMAIN POORLY UNDERSTOOD. HERE WE DETERMINED GENOME-WIDE CHANGES IN DNA METHYLATION IN THE NERVOUS SYSTEM IN NEUROPATHIC PAIN. SPINAL NERVE LIGATION (SNL), BUT NOT PACLITAXEL TREATMENT, IN MALE SPRAGUE DAWLEY RATS INDUCED A CONSISTENT LOW-LEVEL HYPOMETHYLATION IN THE CPG SITES IN THE DRG DURING THE ACUTE AND CHRONIC PHASES OF NEUROPATHIC PAIN. DNA METHYLATION REMODELING IN THE DRG OCCURRED EARLY AFTER SNL AND PERSISTED FOR AT LEAST 3 WEEKS. SNL CAUSED DNA METHYLATION CHANGES AT 8% OF CPG SITES WITH PREVAILING HYPOMETHYLATION OUTSIDE OF CPG ISLANDS, IN INTRONS, INTERGENIC REGIONS, AND REPETITIVE SEQUENCES. IN CONTRAST, SNL CAUSED MORE GAINS OF METHYLATION IN THE SPINAL CORD AND PREFRONTAL CORTEX. THE DNA METHYLATION CHANGES IN THE INJURED DRGS RECAPITULATED DEVELOPMENTAL REPROGRAMMING AT THE NEONATAL STAGE. METHYLATION REPROGRAMMING WAS CORRELATED WITH INCREASED GENE EXPRESSION VARIABILITY. A DIET DEFICIENT IN METHYL DONORS INDUCED HYPOMETHYLATION AND PAIN HYPERSENSITIVITY. INTRATHECAL ADMINISTRATION OF THE DNA METHYLTRANSFERASE INHIBITOR RG108 CAUSED LONG-LASTING PAIN HYPERSENSITIVITY. DNA METHYLATION REPROGRAMMING IN THE DRG THUS CONTRIBUTES TO NERVE INJURY-INDUCED CHRONIC PAIN. RESTORING DNA METHYLATION MAY REPRESENT A NEW THERAPEUTIC APPROACH TO TREAT NEUROPATHIC PAIN.SIGNIFICANCE STATEMENT EPIGENETIC MECHANISMS ARE CRITICALLY INVOLVED IN THE TRANSITION FROM ACUTE TO CHRONIC PAIN AFTER NERVE INJURY. HOWEVER, GENOME-WIDE CHANGES IN DNA METHYLATION IN THE NERVOUS SYSTEM AND THEIR ROLES IN NEUROPATHIC PAIN DEVELOPMENT REMAIN UNCLEAR. HERE WE USED DIGITAL RESTRICTION ENZYME ANALYSIS OF METHYLATION TO QUANTITATIVELY DETERMINE GENOME-WIDE DNA METHYLATION CHANGES CAUSED BY NERVE INJURY. WE SHOWED THAT NERVE INJURY CAUSED DNA METHYLATION CHANGES AT 8% OF CPG SITES WITH PREVAILING HYPOMETHYLATION OUTSIDE OF CPG ISLANDS IN THE DORSAL ROOT GANGLION. REDUCING DNA METHYLATION INDUCED PAIN HYPERSENSITIVITY, WHEREAS INCREASING DNA METHYLATION ATTENUATED NEUROPATHIC PAIN. THESE FINDINGS EXTEND OUR UNDERSTANDING OF THE EPIGENETIC MECHANISM OF CHRONIC NEUROPATHIC PAIN AND SUGGEST NEW STRATEGIES TO TREAT NERVE INJURY-INDUCED CHRONIC PAIN. 2018 15 1161 43 CONTINUOUS DEVELOPMENTAL AND EARLY LIFE TRICHLOROETHYLENE EXPOSURE PROMOTED DNA METHYLATION ALTERATIONS IN POLYCOMB PROTEIN BINDING SITES IN EFFECTOR/MEMORY CD4(+) T CELLS. TRICHLOROETHYLENE (TCE) IS AN INDUSTRIAL SOLVENT AND DRINKING WATER POLLUTANT ASSOCIATED WITH CD4(+) T CELL-MEDIATED AUTOIMMUNITY. IN OUR MOUSE MODEL, DISCONTINUATION OF TCE EXPOSURE DURING ADULTHOOD AFTER DEVELOPMENTAL EXPOSURE DID NOT PREVENT IMMUNOTOXICITY. TO DETERMINE WHETHER PERSISTENT EFFECTS WERE LINKED TO EPIGENETIC CHANGES WE CONDUCTED WHOLE GENOME REDUCED REPRESENTATION BISULFITE SEQUENCING (RRBS) TO EVALUATE METHYLATION OF CPG SITES IN AUTOSOMAL CHROMOSOMES IN ACTIVATED EFFECTOR/MEMORY CD4(+) T CELLS. FEMALE MRL+/+ MICE WERE EXPOSED TO VEHICLE CONTROL OR TCE IN THE DRINKING WATER FROM GESTATION UNTIL ~37 WEEKS OF AGE [POSTNATAL DAY (PND) 259]. IN A SUBSET OF MICE, TCE EXPOSURE WAS DISCONTINUED AT ~22 WEEKS OF AGE (PND 154). AT PND 259, RRBS ASSESSMENT REVEALED MORE GLOBAL METHYLATION CHANGES IN THE CONTINUOUS EXPOSURE GROUP VS. THE DISCONTINUOUS EXPOSURE GROUP. A MAJORITY OF THE DIFFERENTIALLY METHYLATED CPG REGIONS (DMRS) ACROSS PROMOTERS, ISLANDS, AND REGULATORY ELEMENTS WERE HYPERMETHYLATED (~90%). HOWEVER, CONTINUOUS DEVELOPMENTAL TCE EXPOSURE ALTERED THE METHYLATION OF 274 CPG SITES IN PROMOTERS AND CPG ISLANDS. IN CONTRAST, ONLY 4 CPG ISLAND REGIONS WERE DIFFERENTIALLY METHYLATED (HYPERMETHYLATED) IN THE DISCONTINUOUS GROUP. INTERESTINGLY, 2 OF THESE 4 SITES WERE ALSO HYPERMETHYLATED IN THE CONTINUOUS EXPOSURE GROUP, AND BOTH OF THESE ISLAND REGIONS ARE ASSOCIATED WITH LYSINE 27 ON HISTONE H3 (H3K27) INVOLVED IN POLYCOMB COMPLEX-DEPENDENT TRANSCRIPTIONAL REPRESSION VIA H3K27 TRI-METHYLATION. CPG SITES WERE OVERLAPPED WITH THE OPEN REGULATORY ANNOTATION DATABASE. UNLIKE THE DISCONTINUOUS GROUP, CONTINUOUS TCE TREATMENT RESULTED IN 129 DMRS INCLUDING 12 UNIQUE TRANSCRIPTION FACTORS AND REGULATORY ELEMENTS; 80% OF WHICH WERE ENRICHED FOR ONE OR MORE POLYCOMB GROUP (PCG) PROTEIN BINDING REGIONS (I.E., SUZ12, EZH2, JARID2, AND MTF2). PATHWAY ANALYSIS OF THE DMRS INDICATED THAT TCE PRIMARILY ALTERED THE METHYLATION OF GENES ASSOCIATED WITH REGULATION OF CELLULAR METABOLISM AND CELL SIGNALING. THE RESULTS DEMONSTRATED THAT CONTINUOUS DEVELOPMENTAL EXPOSURE TO TCE DIFFERENTIALLY METHYLATED BINDING SITES OF PCG PROTEINS IN EFFECTOR/MEMORY CD4(+) CELLS. THERE WERE MINIMAL YET POTENTIALLY BIOLOGICALLY SIGNIFICANT EFFECTS THAT OCCURRED WHEN EXPOSURE WAS DISCONTINUED. THESE RESULTS POINT TOWARD A NOVEL MECHANISM BY WHICH CHRONIC DEVELOPMENTAL TCE EXPOSURE MAY ALTER TERMINALLY DIFFERENTIATED CD4(+) T CELL FUNCTION IN ADULTHOOD. 2019 16 3810 49 INTRATHECAL 5-AZACYTIDINE INHIBITS GLOBAL DNA METHYLATION AND METHYL- CPG-BINDING PROTEIN 2 EXPRESSION AND ALLEVIATES NEUROPATHIC PAIN IN RATS FOLLOWING CHRONIC CONSTRICTION INJURY. THE PATHOGENESIS OF NEUROPATHIC PAIN REMAINS LARGELY UNKNOWN. EPIGENETIC MECHANISMS MAY PLAY A MAJOR ROLE IN REGULATING EXPRESSION OF PRO- OR ANTINOCICEPTIVE GENES. DNA METHYLATION IS A MAJOR EPIGENETIC MECHANISM IN VERTEBRATES, AND METHYL- CPG-BINDING PROTEIN 2 (MECP2) IS DIRECTLY INVOLVED IN METHYLATION-MEDIATED GENE SILENCING. TO DETERMINE HOW CHANGES IN GLOBAL DNA METHYLATION AND MECP2 EXPRESSION OCCUR FOLLOWING CHRONIC CONSTRICTION INJURY (CCI) AND HOW REPRESSION OF DNA METHYLATION AFFECTS THESE CHANGES AND ATTENUATES NEUROPATHIC PAIN, WE USED INTRATHECAL 5-AZACYTIDINE, A DNA METHYLTRANSFERASE INHIBITOR, IN CCI RATS. RATS RECEIVED 0.9% SALINE OR 5-AZACYTIDINE (10MUMOL.D(-1)) VIA SPINAL INJECTION ONCE DAILY FROM DAY 3 TO DAY 14 AFTER CCI SURGERY. GLOBAL DNA METHYLATION AND MECP2 EXPRESSION INCREASED IN THE SPINAL CORD IN CCI RATS ON DAY 14 AFTER CCI SURGERY. MECHANICAL ALLODYNIA AND THERMAL HYPERALGESIA INDUCED BY CCI WERE ATTENUATED BY INTRATHECAL 5-AZACYTIDINE FROM DAY 5 TO DAY 14 AFTER CCI SURGERY. THE INCREASES IN GLOBAL DNA METHYLATION AND MECP2 EXPRESSION IN THE SPINAL CORD IN CCI RATS WERE ALSO SIGNIFICANTLY INHIBITED BY INTRATHECAL 5-AZACYTIDINE. THESE RESULTS DEMONSTRATE THAT INCREASED GLOBAL DNA METHYLATION AND MECP2 EXPRESSION IN THE SPINAL CORD AFTER NERVE DAMAGE MAY PLAY AN IMPORTANT ROLE IN NEUROPATHIC PAIN. 5-AZACYTIDINE SHOWS POTENTIAL FOR TREATING NEUROPATHIC PAIN. 2011 17 3410 48 HOXA5 UNDERGOES DYNAMIC DNA METHYLATION AND TRANSCRIPTIONAL REPRESSION IN THE ADIPOSE TISSUE OF MICE EXPOSED TO HIGH-FAT DIET. BACKGROUND/OBJECTIVES: THE GENOMIC BASES OF THE ADIPOSE TISSUE ABNORMALITIES INDUCED BY CHRONIC POSITIVE CALORIE EXCESS HAVE BEEN ONLY PARTIALLY ELUCIDATED. WE ADOPTED A GENOME-WIDE APPROACH TO DIRECTLY TEST WHETHER LONG-TERM HIGH-FAT DIET (HFD) EXPOSURE AFFECTS THE DNA METHYLATION PROFILE OF THE MOUSE ADIPOSE TISSUE AND TO IDENTIFY THE FUNCTIONAL CONSEQUENCES OF THESE CHANGES. SUBJECTS/METHODS: WE HAVE USED EPIDIDYMAL FAT OF MICE FED EITHER HIGH-FAT (HFD) OR REGULAR CHOW (STD) DIET FOR 5 MONTHS AND PERFORMED GENOME-WIDE DNA METHYLATION ANALYSES BY METHYLATED DNA IMMUNOPRECIPITATION SEQUENCING (MEDIP-SEQ). MOUSE HOMEOBOX (HOX) GENE DNA METHYLATION PCR, RT-QPCR AND BISULPHITE SEQUENCING ANALYSES WERE THEN PERFORMED. RESULTS: MICE FED THE HFD PROGRESSIVELY EXPANDED THEIR ADIPOSE MASS ACCOMPANIED BY A SIGNIFICANT DECREASE IN GLUCOSE TOLERANCE (P<0.001) AND INSULIN SENSITIVITY (P<0.05). MEDIP-SEQ DATA ANALYSIS REVEALED A UNIFORM DISTRIBUTION OF DIFFERENTIALLY METHYLATED REGIONS (DMR) THROUGH THE ENTIRE ADIPOCYTE GENOME, WITH A HIGHER NUMBER OF HYPERMETHYLATED REGIONS IN HFD MICE (P<0.005). THIS DIFFERENT METHYLATION PROFILE WAS ACCOMPANIED BY INCREASED EXPRESSION OF THE DNMT3A DNA METHYLTRANSFERASE (DNMT; P<0.05) AND THE METHYL-CPG-BINDING DOMAIN PROTEIN MBD3 (P<0.05) GENES IN HFD MICE. GENE ONTOLOGY ANALYSIS REVEALED THAT, IN THE HFD-TREATED MICE, THE HOX FAMILY OF DEVELOPMENT GENES WAS HIGHLY ENRICHED IN DIFFERENTIALLY METHYLATED GENES (P=0.008). TO VALIDATE THIS FINDING, HOXA5, WHICH IS IMPLICATED IN FAT TISSUE DIFFERENTIATION AND REMODELING, HAS BEEN SELECTED AND ANALYZED BY BISULPHITE SEQUENCING, CONFIRMING HYPERMETHYLATION IN THE ADIPOSE TISSUE FROM THE HFD MICE. HOXA5 HYPERMETHYLATION WAS ASSOCIATED WITH DOWNREGULATION OF HOXA5 MRNA AND PROTEIN EXPRESSION. FEEDING ANIMALS PREVIOUSLY EXPOSED TO THE HFD WITH A STANDARD CHOW DIET FOR TWO FURTHER MONTHS IMPROVED THE METABOLIC PHENOTYPE OF THE ANIMALS, ACCOMPANIED BY RETURN OF HOXA5 METHYLATION AND EXPRESSION LEVELS (P<0.05) TO VALUES SIMILAR TO THOSE OF THE CONTROL MICE MAINTAINED UNDER STANDARD CHOW. CONCLUSIONS: HFD INDUCES ADIPOSE TISSUE ABNORMALITIES ACCOMPANIED BY EPIGENETIC CHANGES AT THE HOXA5 ADIPOSE TISSUE REMODELING GENE. 2016 18 1433 40 DIFFERENTIAL GENOME-WIDE ARRAY-BASED METHYLATION PROFILES IN PROGNOSTIC SUBSETS OF CHRONIC LYMPHOCYTIC LEUKEMIA. GLOBAL HYPOMETHYLATION AND REGIONAL HYPERMETHYLATION ARE WELL-KNOWN EPIGENETIC FEATURES OF CANCER; HOWEVER, IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), STUDIES ON GENOME-WIDE EPIGENETIC MODIFICATIONS ARE LIMITED. HERE, WE ANALYZED THE GLOBAL METHYLATION PROFILES IN CLL, BY APPLYING HIGH-RESOLUTION METHYLATION MICROARRAYS (27,578 CPG SITES) TO 23 CLL SAMPLES, BELONGING TO THE IMMUNOGLOBULIN HEAVY-CHAIN VARIABLE (IGHV) MUTATED (FAVORABLE) AND IGHV UNMUTATED/IGHV3-21 (POOR-PROGNOSTIC) SUBSETS. OVERALL, RESULTS DEMONSTRATED SIGNIFICANT DIFFERENCES IN METHYLATION PATTERNS BETWEEN THESE SUBGROUPS. SPECIFICALLY, IN IGHV UNMUTATED CLL, WE IDENTIFIED METHYLATION OF 7 KNOWN OR CANDIDATE TUMOR SUPPRESSOR GENES (EG, VHL, ABI3, AND IGSF4) AS WELL AS 8 UNMETHYLATED GENES INVOLVED IN CELL PROLIFERATION AND TUMOR PROGRESSION (EG, ADORA3 AND PRF1 ENHANCING THE NUCLEAR FACTOR-KAPPAB AND MITOGEN-ACTIVATED PROTEIN KINASE PATHWAYS, RESPECTIVELY). IN CONTRAST, THESE LATTER GENES WERE SILENCED BY METHYLATION IN IGHV MUTATED PATIENTS. THE ARRAY DATA WERE VALIDATED FOR SELECTED GENES USING METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION, QUANTITATIVE REVERSE TRANSCRIPTASE-POLYMERASE CHAIN REACTION, AND BISULFITE SEQUENCING. FINALLY, THE SIGNIFICANCE OF DNA METHYLATION IN REGULATING GENE PROMOTERS WAS SHOWN BY REINDUCING 4 METHYLATED TUMOR SUPPRESSOR GENES (EG, VHL AND ABI3) IN IGHV UNMUTATED SAMPLES USING THE METHYL-INHIBITOR 5-AZA-2'-DEOXYCYTIDINE. TAKEN TOGETHER, OUR DATA FOR THE FIRST TIME REVEAL DIFFERENCES IN GLOBAL METHYLATION PROFILES BETWEEN PROGNOSTIC SUBSETS OF CLL, WHICH MAY UNFOLD EPIGENETIC SILENCING MECHANISMS INVOLVED IN CLL PATHOGENESIS. 2010 19 812 43 CHANGES IN DNA METHYLATION PROFILES OF MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME PATIENTS REFLECT SYSTEMIC DYSFUNCTIONS. BACKGROUND: MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A LIFELONG DEBILITATING DISEASE WITH A COMPLEX PATHOLOGY NOT YET CLEARLY DEFINED. SUSCEPTIBILITY TO ME/CFS INVOLVES GENETIC PREDISPOSITION AND EXPOSURE TO ENVIRONMENTAL FACTORS, SUGGESTING AN EPIGENETIC ASSOCIATION. EPIGENETIC STUDIES WITH OTHER ME/CFS COHORTS HAVE USED ARRAY-BASED TECHNOLOGY TO IDENTIFY DIFFERENTIALLY METHYLATED INDIVIDUAL SITES. CHANGES IN RNA QUANTITIES AND PROTEIN ABUNDANCE HAVE BEEN DOCUMENTED IN OUR PREVIOUS INVESTIGATIONS WITH THE SAME ME/CFS COHORT USED FOR THIS STUDY. RESULTS: DNA FROM A WELL-CHARACTERISED NEW ZEALAND COHORT OF 10 ME/CFS PATIENTS AND 10 AGE-/SEX-MATCHED HEALTHY CONTROLS WAS ISOLATED FROM PERIPHERAL BLOOD MONONUCLEAR (PBMC) CELLS, AND USED TO GENERATE REDUCED GENOME-SCALE DNA METHYLATION MAPS USING REDUCED REPRESENTATION BISULPHITE SEQUENCING (RRBS). THE SEQUENCING DATA WERE ANALYSED UTILISING THE DMAP ANALYSIS PIPELINE TO IDENTIFY DIFFERENTIALLY METHYLATED FRAGMENTS, AND THE METHYLKIT PIPELINE WAS USED TO QUANTIFY METHYLATION DIFFERENCES AT INDIVIDUAL CPG SITES. DMAP IDENTIFIED 76 DIFFERENTIALLY METHYLATED FRAGMENTS AND METHYLKIT IDENTIFIED 394 DIFFERENTIALLY METHYLATED CYTOSINES THAT INCLUDED BOTH HYPER- AND HYPO-METHYLATION. FOUR CLUSTERS WERE IDENTIFIED WHERE DIFFERENTIALLY METHYLATED DNA FRAGMENTS OVERLAPPED WITH OR WERE WITHIN CLOSE PROXIMITY TO MULTIPLE DIFFERENTIALLY METHYLATED INDIVIDUAL CYTOSINES. THESE CLUSTERS IDENTIFIED REGULATORY REGIONS FOR 17 PROTEIN ENCODING GENES RELATED TO METABOLIC AND IMMUNE ACTIVITY. ANALYSIS OF DIFFERENTIALLY METHYLATED GENE BODIES (EXONS/INTRONS) IDENTIFIED 122 UNIQUE GENES. COMPARISON WITH OTHER STUDIES ON PBMCS FROM ME/CFS PATIENTS AND CONTROLS WITH ARRAY TECHNOLOGY SHOWED 59% OF THE GENES IDENTIFIED IN THIS STUDY WERE ALSO FOUND IN ONE OR MORE OF THESE STUDIES. FUNCTIONAL PATHWAY ENRICHMENT ANALYSIS IDENTIFIED 30 ASSOCIATED PATHWAYS. THESE INCLUDED IMMUNE, METABOLIC AND NEUROLOGICAL-RELATED FUNCTIONS DIFFERENTIALLY REGULATED IN ME/CFS PATIENTS COMPARED TO THE MATCHED HEALTHY CONTROLS. CONCLUSIONS: MAJOR DIFFERENCES WERE IDENTIFIED IN THE DNA METHYLATION PATTERNS OF ME/CFS PATIENTS THAT CLEARLY DISTINGUISHED THEM FROM THE HEALTHY CONTROLS. OVER HALF FOUND IN GENE BODIES WITH RRBS IN THIS STUDY HAD BEEN IDENTIFIED IN OTHER ME/CFS STUDIES USING THE SAME CELLS BUT WITH ARRAY TECHNOLOGY. WITHIN THE ENRICHED FUNCTIONAL IMMUNE, METABOLIC AND NEUROLOGICAL PATHWAYS, A NUMBER OF ENRICHED NEUROTRANSMITTER AND NEUROPEPTIDE REACTOME PATHWAYS HIGHLIGHTED A DISTURBED NEUROLOGICAL PATHOPHYSIOLOGY WITHIN THE PATIENT GROUP. 2020 20 2639 31 EPIGENOMIC ANALYSIS DETECTS WIDESPREAD GENE-BODY DNA HYPOMETHYLATION IN CHRONIC LYMPHOCYTIC LEUKEMIA. WE HAVE EXTENSIVELY CHARACTERIZED THE DNA METHYLOMES OF 139 PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) WITH MUTATED OR UNMUTATED IGHV AND OF SEVERAL MATURE B-CELL SUBPOPULATIONS THROUGH THE USE OF WHOLE-GENOME BISULFITE SEQUENCING AND HIGH-DENSITY MICROARRAYS. THE TWO MOLECULAR SUBTYPES OF CLL HAVE DIFFERING DNA METHYLOMES THAT SEEM TO REPRESENT EPIGENETIC IMPRINTS FROM DISTINCT NORMAL B-CELL SUBPOPULATIONS. DNA HYPOMETHYLATION IN THE GENE BODY, TARGETING MOSTLY ENHANCER SITES, WAS THE MOST FREQUENT DIFFERENCE BETWEEN NAIVE AND MEMORY B CELLS AND BETWEEN THE TWO MOLECULAR SUBTYPES OF CLL AND NORMAL B CELLS. ALTHOUGH DNA METHYLATION AND GENE EXPRESSION WERE POORLY CORRELATED, WE IDENTIFIED GENE-BODY CPG DINUCLEOTIDES WHOSE METHYLATION WAS POSITIVELY OR NEGATIVELY ASSOCIATED WITH EXPRESSION. WE HAVE ALSO RECOGNIZED A DNA METHYLATION SIGNATURE THAT DISTINGUISHES NEW CLINICO-BIOLOGICAL SUBTYPES OF CLL. WE PROPOSE AN EPIGENOMIC SCENARIO IN WHICH DIFFERENTIAL METHYLATION IN THE GENE BODY MAY HAVE FUNCTIONAL AND CLINICAL IMPLICATIONS IN LEUKEMOGENESIS. 2012