1 839 122 CHEMO-ENZYMATIC FLUORESCENCE LABELING OF GENOMIC DNA FOR SIMULTANEOUS DETECTION OF GLOBAL 5-METHYLCYTOSINE AND 5-HYDROXYMETHYLCYTOSINE. 5-METHYLCYTOSINE AND 5-HYDROXYMETHYLCYTOSINE ARE EPIGENETIC MODIFICATIONS INVOLVED IN GENE REGULATION AND CANCER. WE PRESENT A NEW, SIMPLE, AND HIGH-THROUGHPUT PLATFORM FOR MULTI-COLOR EPIGENETIC ANALYSIS. THE NOVELTY OF OUR APPROACH IS THE ABILITY TO MULTIPLEX METHYLATION AND DE-METHYLATION SIGNALS IN THE SAME ASSAY. WE UTILIZE AN ENGINEERED METHYLTRANSFERASE ENZYME THAT RECOGNIZES AND LABELS ALL UNMODIFIED CPG SITES WITH A FLUORESCENT COFACTOR. IN COMBINATION WITH THE ALREADY ESTABLISHED LABELING OF THE DE-METHYLATION MARK 5-HYDROXYMETHYLCYTOSINE VIA ENZYMATIC GLYCOSYLATION, WE OBTAINED A ROBUST PLATFORM FOR SIMULTANEOUS EPIGENETIC ANALYSIS OF THESE MARKS. WE ASSESSED THE GLOBAL EPIGENETIC LEVELS IN MULTIPLE SAMPLES OF COLORECTAL CANCER AND OBSERVED A 3.5-FOLD REDUCTION IN 5HMC LEVELS BUT NO CHANGE IN DNA METHYLATION LEVELS BETWEEN SICK AND HEALTHY INDIVIDUALS. WE ALSO MEASURED EPIGENETIC MODIFICATIONS IN CHRONIC LYMPHOCYTIC LEUKEMIA AND OBSERVED A DECREASE IN BOTH MODIFICATION LEVELS (5-HYDROXYMETHYLCYTOSINE: WHOLE BLOOD 30 %; PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) 40 %. 5-METHYLCYTOSINE: WHOLE BLOOD 53 %; PBMCS 48 %). OUR FINDINGS PROPOSE USING A SIMPLE BLOOD TEST AS A VIABLE METHOD FOR ANALYSIS, SIMPLIFYING SAMPLE HANDLING IN DIAGNOSTICS. IMPORTANTLY, OUR RESULTS HIGHLIGHT THE ASSAY'S POTENTIAL FOR EPIGENETIC EVALUATION OF CLINICAL SAMPLES, BENEFITING RESEARCH AND PATIENT MANAGEMENT. 2023 2 1345 39 DETECTION OF DIFFERENTIALLY METHYLATED REGIONS USING BAYES FACTOR FOR ORDINAL GROUP RESPONSES. RESEARCHERS IN GENOMICS ARE INCREASINGLY INTERESTED IN EPIGENETIC FACTORS SUCH AS DNA METHYLATION, BECAUSE THEY PLAY AN IMPORTANT ROLE IN REGULATING GENE EXPRESSION WITHOUT CHANGES IN THE DNA SEQUENCE. THERE HAVE BEEN SIGNIFICANT ADVANCES IN DEVELOPING STATISTICAL METHODS TO DETECT DIFFERENTIALLY METHYLATED REGIONS (DMRS) ASSOCIATED WITH BINARY DISEASE STATUS. MOST OF THESE METHODS ARE BEING DEVELOPED FOR DETECTING DIFFERENTIAL METHYLATION RATES BETWEEN CASES AND CONTROLS. WE CONSIDER MULTIPLE SEVERITY LEVELS OF DISEASE, AND DEVELOP A BAYESIAN STATISTICAL METHOD TO DETECT THE REGION WITH INCREASING (OR DECREASING) METHYLATION RATES AS THE DISEASE SEVERITY INCREASES. PATIENTS ARE CLASSIFIED INTO MORE THAN TWO GROUPS, BASED ON THE DISEASE SEVERITY (E.G., STAGES OF CANCER), AND DMRS ARE DETECTED BY USING MOVING WINDOWS ALONG THE GENOME. WITHIN EACH WINDOW, THE BAYES FACTOR IS CALCULATED TO TEST THE HYPOTHESIS OF MONOTONIC INCREASE IN METHYLATION RATES CORRESPONDING TO SEVERITY OF THE DISEASE VERSUS NO DIFFERENCE. A MIXED-EFFECT MODEL IS USED TO INCORPORATE THE CORRELATION OF METHYLATION RATES OF NEARBY CPG SITES IN THE REGION. RESULTS FROM EXTENSIVE SIMULATION INDICATE THAT OUR PROPOSED METHOD IS STATISTICALLY VALID AND REASONABLY POWERFUL. WE DEMONSTRATE OUR APPROACH ON A BISULFITE SEQUENCING DATASET FROM A CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) STUDY. 2019 3 277 34 AGE-RELATED EPIGENOME-WIDE DNA METHYLATION AND HYDROXYMETHYLATION IN LONGITUDINAL MOUSE BLOOD. DNA METHYLATION AT CYTOSINE-PHOSPHATE-GUANINE (CPG) DINUCLEOTIDES CHANGES AS A FUNCTION OF AGE IN HUMANS AND ANIMAL MODELS, A PROCESS THAT MAY CONTRIBUTE TO CHRONIC DISEASE DEVELOPMENT. RECENT STUDIES HAVE INVESTIGATED THE ROLE OF AN OXIDIZED FORM OF DNA METHYLATION - 5-HYDROXYMETHYLCYTOSINE (5HMC) - IN THE EPIGENOME, BUT ITS CONTRIBUTION TO AGE-RELATED DNA METHYLATION REMAINS UNCLEAR. WE TESTED THE HYPOTHESIS THAT 5HMC CHANGES WITH AGE, BUT IN A DIRECTION OPPOSITE TO 5-METHYLCYTOSINE (5MC), POTENTIALLY PLAYING A DISTINCT ROLE IN AGING. TO CHARACTERIZE EPIGENETIC AGING, GENOME-WIDE 5MC AND 5HMC WERE MEASURED IN LONGITUDINAL BLOOD SAMPLES (2, 4, AND 10 MONTHS OF AGE) FROM ISOGENIC MICE USING TWO SEQUENCING METHODS - ENHANCED REDUCED REPRESENTATION BISULFITE SEQUENCING AND HYDROXYMETHYLATED DNA IMMUNOPRECIPITATION SEQUENCING. EXAMINING THE EPIGENOME BY AGE, WE IDENTIFIED 28,196 UNIQUE DIFFERENTIALLY METHYLATED CPGS (DMCS) AND 8,613 DIFFERENTIALLY HYDROXYMETHYLATED REGIONS (DHMRS). MOUSE BLOOD SHOWED A GENERAL PATTERN OF EPIGENOME-WIDE HYPERMETHYLATION AND HYPO-HYDROXYMETHYLATION WITH AGE. COMPARING AGE-RELATED DMCS AND DHMRS, 1,854 ANNOTATED GENES SHOWED BOTH DIFFERENTIAL 5MC AND 5HMC, INCLUDING ONE GENE - NFIC - AT FIVE CPGS IN THE SAME 250 BP CHROMOSOMAL REGION. AT THIS REGION, 5MC AND 5HMC LEVELS BOTH DECREASED WITH AGE. REFLECTING THESE AGE-RELATED EPIGENETIC CHANGES, NFIC RNA EXPRESSION IN BLOOD DECREASED WITH AGE, SUGGESTING THAT AGE-RELATED REGULATION OF THIS GENE MAY BE DRIVEN BY 5HMC, NOT CANONICAL DNA METHYLATION. COMBINED, OUR GENOME-WIDE RESULTS SHOW AGE-RELATED DIFFERENTIAL 5MC AND 5HMC, AS WELL AS SOME EVIDENCE THAT CHANGES IN 5HMC MAY DRIVE AGE-RELATED DNA METHYLATION AND GENE EXPRESSION. 2018 4 6684 25 VALIDATION OF AN LC-MS BASED APPROACH FOR PROFILING HISTONES IN CHRONIC LYMPHOCYTIC LEUKEMIA. THE IN VITRO EVALUATION OF HISTONES AND THEIR PTMS HAS DRAWN SUBSTANTIAL INTEREST IN THE DEVELOPMENT OF EPIGENETIC THERAPIES. THE DIFFERENTIAL EXPRESSION OF HISTONE ISOFORMS MAY SERVE AS A POTENTIAL MARKER IN THE CLASSIFICATION OF DISEASES AFFECTED BY CHROMATIN ABNORMALITIES. IN THIS STUDY, PROTEIN PROFILING BY LC AND MS WAS USED TO EXPLORE DIFFERENCES IN HISTONE COMPOSITION IN PRIMARY CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) CELLS. EXTENSIVE METHOD VALIDATIONS WERE PERFORMED TO DETERMINE THE EXPERIMENTAL VARIANCES THAT WOULD IMPACT HISTONE RELATIVE ABUNDANCE. THE RESULTING DATA DEMONSTRATED THAT THE PROPOSED METHODOLOGY WAS SUITABLE FOR THE ANALYSIS OF HISTONE PROFILES. IN 4 NORMAL INDIVIDUALS AND 40 CLL PATIENTS, A SIGNIFICANT DECREASE IN THE RELATIVE ABUNDANCE OF HISTONE H2A VARIANTS (H2AFL AND H2AFA/M*) WAS OBSERVED IN PRIMARY CLL CELLS AS COMPARED TO NORMAL B CELLS. PROTEIN IDENTITIES WERE DETERMINED USING HIGH MASS ACCURACY MS AND SHOTGUN PROTEOMICS. 2009 5 5706 44 SINGLE-MOLECULE QUANTIFICATION OF 5-HYDROXYMETHYLCYTOSINE FOR DIAGNOSIS OF BLOOD AND COLON CANCERS. BACKGROUND: THE DNA MODIFICATION 5-HYDROXYMETHYLCYTOSINE (5HMC) IS NOW REFERRED TO AS THE SIXTH BASE OF DNA WITH EVIDENCE OF TISSUE-SPECIFIC PATTERNS AND CORRELATION WITH GENE REGULATION AND EXPRESSION. THIS EPIGENETIC MARK WAS RECENTLY REPORTED AS A POTENTIAL BIOMARKER FOR MULTIPLE TYPES OF CANCER, BUT ITS APPLICATION IN THE CLINIC IS LIMITED BY THE UTILITY OF RECENT 5HMC QUANTIFICATION ASSAYS. WE USE A RECENTLY DEVELOPED, ULTRA-SENSITIVE, FLUORESCENCE-BASED SINGLE-MOLECULE METHOD FOR GLOBAL QUANTIFICATION OF 5HMC IN GENOMIC DNA. THE HIGH SENSITIVITY OF THE METHOD GIVES ACCESS TO PRECISE QUANTIFICATION OF EXTREMELY LOW 5HMC LEVELS COMMON IN MANY CANCERS. METHODS: WE ASSESSED 5HMC LEVELS IN DNA EXTRACTED FROM A SET OF COLON AND BLOOD CANCER SAMPLES AND COMPARED 5HMC LEVELS WITH HEALTHY CONTROLS, IN A SINGLE-MOLECULE APPROACH. RESULTS: USING OUR METHOD, WE OBSERVED A SIGNIFICANTLY REDUCED LEVEL OF 5HMC IN BLOOD AND COLON CANCERS AND COULD DISTINGUISH BETWEEN COLON TUMOR AND COLON TISSUE ADJACENT TO THE TUMOR BASED ON THE GLOBAL LEVELS OF THIS MOLECULAR BIOMARKER. CONCLUSIONS: SINGLE-MOLECULE DETECTION OF 5HMC ALLOWS DISTINGUISHING BETWEEN MALIGNANT AND HEALTHY TISSUE IN CLINICALLY RELEVANT AND ACCESSIBLE TISSUE SUCH AS BLOOD AND COLON. THE PRESENTED METHOD OUTPERFORMS CURRENT COMMERCIALLY AVAILABLE QUANTIFICATION KITS AND MAY POTENTIALLY BE DEVELOPED INTO A WIDELY USED, 5HMC QUANTIFICATION ASSAY FOR RESEARCH AND CLINICAL DIAGNOSTICS. FURTHERMORE, USING THIS METHOD, WE CONFIRM THAT 5HMC IS A GOOD MOLECULAR BIOMARKER FOR DIAGNOSING COLON AND VARIOUS TYPES OF BLOOD CANCER. 2017 6 3077 29 GENOME-WIDE METHYL-SEQ ANALYSIS OF BLOOD-BRAIN TARGETS OF GLUCOCORTICOID EXPOSURE. CHRONIC EXPOSURE TO GLUCOCORTICOIDS (GCS) CAN LEAD TO PSYCHIATRIC COMPLICATIONS THROUGH EPIGENETIC MECHANISMS SUCH AS DNA METHYLATION (DNAM). WE SOUGHT TO DETERMINE WHETHER EPIGENETIC CHANGES IN A PERIPHERAL TISSUE CAN SERVE AS A SURROGATE FOR THOSE IN A RELATIVELY INACCESSIBLE TISSUE SUCH AS THE BRAIN. DNA EXTRACTED FROM THE HIPPOCAMPUS AND BLOOD OF MICE TREATED WITH GCS OR VEHICLE SOLUTION WAS ASSAYED USING A GENOME-WIDE DNAM PLATFORM (METHYL-SEQ) TO IDENTIFY DIFFERENTIALLY METHYLATED REGIONS (DMRS) INDUCED BY GC TREATMENT. WE OBSERVED THAT APPROXIMATELY 70% OF THE DMRS IN BOTH TISSUES LOST METHYLATION FOLLOWING GC TREATMENT. OF THE 3,095 DMRS THAT MAPPED TO THE SAME GENES IN BOTH TISSUES, 1,853 DMRS UNDERWENT DNAM CHANGES IN THE SAME DIRECTION. INTERESTINGLY, ONLY 209 DMRS (<7%) OVERLAPPED IN GENOMIC COORDINATES BETWEEN THE 2 TISSUES, SUGGESTING TISSUE-SPECIFIC DIFFERENCES IN GC-TARGETED LOCI. PATHWAY ANALYSIS SHOWED THAT THE DMR-ASSOCIATED GENES WERE MEMBERS OF PATHWAYS INVOLVED IN METABOLISM, IMMUNE FUNCTION, AND NEURODEVELOPMENT. ALSO, CHANGES IN CELL TYPE COMPOSITION OF BLOOD AND BRAIN WERE EXAMINED BY FLUORESCENCE-ACTIVATED CELL SORTING. SEPARATION OF THE CORTEX INTO NEURONAL AND NON-NEURONAL FRACTIONS AND THE LEUKOCYTES INTO T-CELLS, B-CELLS, AND NEUTROPHILS SHOWED THAT GC-INDUCED METHYLATION CHANGES PRIMARILY OCCURRED IN NEURONS AND T-CELLS, WITH THE BLOOD TISSUE ALSO UNDERGOING A SHIFT IN THE PROPORTION OF CONSTITUENT CELL TYPES WHILE THE PROPORTION OF NEURONS AND GLIA IN THE BRAIN REMAINED STABLE. FROM THE CURRENT PILOT STUDY, WE FOUND THAT DESPITE TISSUE-SPECIFIC EPIGENETIC CHANGES AND CELLULAR HETEROGENEITY, BLOOD CAN SERVE AS A SURROGATE FOR GC-INDUCED CHANGES IN THE BRAIN. 2017 7 59 29 A GENOME-WIDE SCREEN IDENTIFIES FREQUENTLY METHYLATED GENES IN HAEMATOLOGICAL AND EPITHELIAL CANCERS. BACKGROUND: GENETIC AS WELL AS EPIGENETIC ALTERATIONS ARE A HALLMARK OF BOTH EPITHELIAL AND HAEMATOLOGICAL MALIGNANCIES. HIGH THROUGHPUT SCREENS ARE REQUIRED TO IDENTIFY EPIGENETIC MARKERS THAT CAN BE USEFUL FOR DIAGNOSTIC AND PROGNOSTIC PURPOSES ACROSS MALIGNANCIES. RESULTS: HERE WE REPORT FOR THE FIRST TIME THE USE OF THE MIRA ASSAY (METHYLATED CPG ISLAND RECOVERY ASSAY) IN COMBINATION WITH GENOME-WIDE CPG ISLAND ARRAYS TO IDENTIFY EPIGENETIC MOLECULAR MARKERS IN CHILDHOOD ACUTE LYMPHOBLASTIC LEUKEMIA (ALL) ON A GENOME-WIDE SCALE. WE IDENTIFIED 30 GENES DEMONSTRATING METHYLATION FREQUENCIES OF > OR =25% IN CHILDHOOD ALL, NINE GENES SHOWED SIGNIFICANTLY DIFFERENT METHYLATION FREQUENCIES IN B VS T-ALL. FOR MAJORITY OF THE GENES EXPRESSION COULD BE RESTORED IN METHYLATED LEUKEMIA LINES AFTER TREATMENT WITH 5-AZADC. FORTY-FOUR PERCENT OF THE GENES REPRESENT TARGETS OF THE POLYCOMB COMPLEX. IN CHRONIC MYELOID LEUKEMIA (CML) TWO OF THE GENES, (TFAP2A AND EBF2), DEMONSTRATED INCREASED METHYLATION IN BLAST CRISIS COMPARED TO CHRONIC PHASE (P < 0.05). FURTHERMORE HYPERMETHYLATION OF AN AUTOPHAGY RELATED GENE ATG16L2 WAS ASSOCIATED WITH POORER PROGNOSIS IN TERMS OF MOLECULAR RESPONSE TO IMATINIB TREATMENT. LASTLY WE DEMONSTRATED THAT TEN OF THESE GENES WERE ALSO FREQUENTLY METHYLATED IN COMMON EPITHELIAL CANCERS. CONCLUSION: IN SUMMARY WE HAVE IDENTIFIED A LARGE NUMBER OF GENES SHOWING FREQUENT METHYLATION IN CHILDHOOD ALL, METHYLATION STATUS OF TWO OF THESE GENES IS ASSOCIATED WITH ADVANCED DISEASE IN CML AND METHYLATION STATUS OF ANOTHER GENE IS ASSOCIATED WITH PROGNOSIS. IN ADDITION A SUBSET OF THESE GENES MAY ACT AS EPIGENETIC MARKERS ACROSS HEMATOLOGICAL MALIGNANCIES AS WELL AS COMMON EPITHELIAL CANCERS. 2010 8 1739 38 EARLY DNA METHYLATION CHANGES IN CHILDREN DEVELOPING BETA CELL AUTOIMMUNITY AT A YOUNG AGE. AIMS/HYPOTHESIS: TYPE 1 DIABETES IS A CHRONIC AUTOIMMUNE DISEASE OF COMPLEX AETIOLOGY, INCLUDING A POTENTIAL ROLE FOR EPIGENETIC REGULATION. PREVIOUS EPIGENOMIC STUDIES FOCUSED MAINLY ON CLINICALLY DIAGNOSED INDIVIDUALS. THE AIM OF THE STUDY WAS TO ASSESS EARLY DNA METHYLATION CHANGES ASSOCIATED WITH TYPE 1 DIABETES ALREADY BEFORE THE DIAGNOSIS OR EVEN BEFORE THE APPEARANCE OF AUTOANTIBODIES. METHODS: REDUCED REPRESENTATION BISULPHITE SEQUENCING (RRBS) WAS APPLIED TO STUDY DNA METHYLATION IN PURIFIED CD4(+) T CELL, CD8(+) T CELL AND CD4(-)CD8(-) CELL FRACTIONS OF 226 PERIPHERAL BLOOD MONONUCLEAR CELL SAMPLES LONGITUDINALLY COLLECTED FROM SEVEN TYPE 1 DIABETES-SPECIFIC AUTOANTIBODY-POSITIVE INDIVIDUALS AND CONTROL INDIVIDUALS MATCHED FOR AGE, SEX, HLA RISK AND PLACE OF BIRTH. WE ALSO EXPLORED CORRELATIONS BETWEEN DNA METHYLATION AND GENE EXPRESSION USING RNA SEQUENCING DATA FROM THE SAME SAMPLES. TECHNICAL VALIDATION OF RRBS RESULTS WAS PERFORMED USING PYROSEQUENCING. RESULTS: WE IDENTIFIED 79, 56 AND 45 DIFFERENTIALLY METHYLATED REGIONS IN CD4(+) T CELLS, CD8(+) T CELLS AND CD4(-)CD8(-) CELL FRACTIONS, RESPECTIVELY, BETWEEN TYPE 1 DIABETES-SPECIFIC AUTOANTIBODY-POSITIVE INDIVIDUALS AND CONTROL PARTICIPANTS. THE ANALYSIS OF PRE-SEROCONVERSION SAMPLES IDENTIFIED DNA METHYLATION SIGNATURES AT THE VERY EARLY STAGE OF DISEASE, INCLUDING DIFFERENTIAL METHYLATION AT THE PROMOTER OF IRF5 IN CD4(+) T CELLS. FURTHER, WE VALIDATED RRBS RESULTS USING PYROSEQUENCING AT THE FOLLOWING CPG SITES: CHR19:18118304 IN THE PROMOTER OF ARRDC2; CHR21:47307815 IN THE INTRON OF PCBP3; AND CHR14:81128398 IN THE INTERGENIC REGION NEAR TRAF3 IN CD4(+) T CELLS. CONCLUSIONS/INTERPRETATION: THESE PRELIMINARY RESULTS PROVIDE NOVEL INSIGHTS INTO CELL TYPE-SPECIFIC DIFFERENTIAL EPIGENETIC REGULATION OF GENES, WHICH MAY CONTRIBUTE TO TYPE 1 DIABETES PATHOGENESIS AT THE VERY EARLY STAGE OF DISEASE DEVELOPMENT. SHOULD THESE FINDINGS BE VALIDATED, THEY MAY SERVE AS A POTENTIAL SIGNATURE USEFUL FOR DISEASE PREDICTION AND MANAGEMENT. 2022 9 1486 33 DNA CYTOSINE HYDROXYMETHYLATION LEVELS ARE DISTINCT AMONG NON-OVERLAPPING CLASSES OF PERIPHERAL BLOOD LEUKOCYTES. BACKGROUND: PERIPHERAL BLOOD LEUKOCYTES ARE THE MOST COMMONLY USED SURROGATES TO STUDY EPIGENOME-INDUCED RISK AND EPIGENOMIC RESPONSE TO DISEASE-RELATED STRESS. WE CONSIDERED THE HYPOTHESIS THAT THE VARIOUS CLASSES OF PERIPHERAL LEUKOCYTES DIFFERENTIALLY REGULATE THE SYNTHESIS OF 5-METHYLCYTOSINE (5MCG) AND ITS REMOVAL VIA TEN-ELEVEN TRANSLOCATION (TET) DIOXYGENASE CATALYZED HYDROXYMETHYLATION TO 5-HYDROXYMETHYLCYTOSINE (5HMCG), REFLECTING THEIR RESPONSIVENESS TO ENVIRONMENT. ALTHOUGH IT IS KNOWN THAT REDUCTIONS IN TET1 AND/OR TET2 ACTIVITY LEAD TO THE OVER-PROLIFERATION OF VARIOUS LEUKOCYTE PRECURSORS IN BONE MARROW AND IN DEVELOPMENT OF CHRONIC MYELOMONOCYTIC LEUKEMIA AND MYELOPROLIFERATIVE NEOPLASMS, THE ROLE OF 5MCG HYDROXYMETHYLATION IN PERIPHERAL BLOOD IS LESS WELL STUDIED. RESULTS: WE DEVELOPED SIMPLIFIED PROTOCOLS TO RAPIDLY AND REITERATIVELY ISOLATE NON-OVERLAPPING LEUKOCYTE POPULATIONS FROM A SINGLE SMALL SAMPLE OF FRESH OR FROZEN WHOLE BLOOD. AMONG PERIPHERAL LEUKOCYTE TYPES WE FOUND EXTREME VARIATION IN THE LEVELS OF TRANSCRIPTS ENCODING PROTEINS INVOLVED IN CYTOSINE METHYLATION (DNMT1, 3A, 3B), THE TURNOVER OF 5MC BY DEMETHYLATION (TET1, 2, 3), AND DNA REPAIR (GADD45A, B, G) AND IN THE GLOBAL AND GENE-REGION-SPECIFIC LEVELS OF DNA 5HMCG (CD4+ T CELLS>>CD14+ MONOCYTES>CD16+ NEUTROPHILS>CD19+ B CELLS>CD56+ NK CELLS>SIGLEC8+ EOSINOPHILS>CD8+ T CELLS). CONCLUSIONS: OUR DATA TAKEN TOGETHER SUGGEST A POTENTIAL HIERARCHY OF RESPONSIVENESS AMONG CLASSES OF LEUKOCYTES WITH CD4+, CD8+ T CELLS AND CD14+ MONOCYTES BEING THE MOST DISTINCTLY POISED FOR A RAPID METHYLOME RESPONSE TO PHYSIOLOGICAL STRESS AND DISEASE. 2016 10 2653 33 EPIGENOTYPING IN PERIPHERAL BLOOD CELL DNA AND BREAST CANCER RISK: A PROOF OF PRINCIPLE STUDY. BACKGROUND: EPIGENETIC CHANGES ARE EMERGING AS ONE OF THE MOST IMPORTANT EVENTS IN CARCINOGENESIS. TWO ALTERATIONS IN THE PATTERN OF DNA METHYLATION IN BREAST CANCER (BC) HAVE BEEN PREVIOUSLY REPORTED; ACTIVE ESTROGEN RECEPTOR-ALPHA (ER-ALPHA) IS ASSOCIATED WITH DECREASED METHYLATION OF ER-ALPHA TARGET (ERT) GENES, AND POLYCOMB GROUP TARGET (PCGT) GENES ARE MORE LIKELY THAN OTHER GENES TO HAVE PROMOTER DNA HYPERMETHYLATION IN CANCER. HOWEVER, WHETHER DNA METHYLATION IN NORMAL UNRELATED CELLS IS ASSOCIATED WITH BC RISK AND WHETHER THESE IMPRINTS CAN BE RELATED TO FACTORS WHICH CAN BE MODIFIED BY THE ENVIRONMENT, IS UNCLEAR. METHODOLOGY/PRINCIPAL FINDINGS: USING QUANTITATIVE METHYLATION ANALYSIS IN A CASE-CONTROL STUDY (N = 1,083) WE FOUND THAT DNA METHYLATION OF PERIPHERAL BLOOD CELL DNA PROVIDES GOOD PREDICTION OF BC RISK. WE ALSO REPORT THAT INVASIVE DUCTAL AND INVASIVE LOBULAR BC IS CHARACTERIZED BY TWO DIFFERENT SETS OF GENES, THE LATTER PARTICULAR BY GENES INVOLVED IN THE DIFFERENTIATION OF THE MESENCHYME (PITX2, TITF1, GDNF AND MYOD1). FINALLY WE DEMONSTRATE THAT ONLY ERT GENES PREDICT ER POSITIVE BC; LACK OF PERIPHERAL BLOOD CELL DNA METHYLATION OF ZNF217 PREDICTED BC INDEPENDENT OF AGE AND FAMILY HISTORY (ODDS RATIO 1.49; 95% CONFIDENCE INTERVAL 1.12-1.97; P = 0.006) AND WAS ASSOCIATED WITH ER-ALPHA BIOACTIVITY IN THE CORRESPONDING SERUM. CONCLUSION/SIGNIFICANCE: THIS FIRST LARGE-SCALE EPIGENOTYPING STUDY DEMONSTRATES THAT DNA METHYLATION MAY SERVE AS A LINK BETWEEN THE ENVIRONMENT AND THE GENOME. FACTORS THAT CAN BE MODULATED BY THE ENVIRONMENT (LIKE ESTROGENS) LEAVE AN IMPRINT IN THE DNA OF CELLS THAT ARE UNRELATED TO THE TARGET ORGAN AND INDICATE THE PREDISPOSITION TO DEVELOP A CANCER. FURTHER RESEARCH WILL NEED TO DEMONSTRATE WHETHER DNA METHYLATION PROFILES WILL BE ABLE TO SERVE AS A NEW TOOL TO PREDICT THE RISK OF DEVELOPING CHRONIC DISEASES WITH SUFFICIENT ACCURACY TO GUIDE PREVENTIVE MEASURES. 2008 11 6845 27 [METHYLATION STATUS OF APOPTOSIS GENES AND INTENSITY OF APOPTOTIC DEATH OF PERIPHERAL BLOOD LYMPHOCYTES IN PERSONS CHRONICALLY EXPOSED TO RADIATION]. METHYLATION OF THE CPG ISLANDS OF GENE PROMOTER REGIONS IS THE MOST COMMON EPIGENETIC MODIFICATION INVOLVED IN THE REGULATION OF GENE EXPRESSION. A NUMBER OF STUDIES HAVE SHOWN THAT IONIZING RADIATION CAN CAUSE BOTH HYPER- AND HYPOMETHYLATION OF DNA. ABERRANT METHYLATION AFFECTS CELLULAR PROCESSES AND CAN LEAD TO THE DEVELOPMENT OF VARIOUS PATHOLOGICAL STATES. IN THE LITERATURE, THERE ARE FEW STUDIES ON THE METHYLATION STATUS OF HUMAN DNA A LONG TIME AFTER RADIATION EXPOSURE. HERE, THE METHYLATION LEVEL OF CPG ISLANDS OF THE PROMOTER REGIONS OF APOPTOSIS GENES (BCL2, ATM, MDM2, CDKN1A, STAT3, AND NFKB1), AND ALSO ITS INFLUENCE ON APOPTOSIS OF PERIPHERAL BLOOD LYMPHOCYTES IN CHRONICALLY EXPOSED PERSONS WERE STUDIED. RESIDENTS OF THE SOUTH URAL REGION WHO WERE CHRONICALLY EXPOSED TO RADIATION (AFTER DISCHARGES OF RADIOACTIVE WASTES INTO THE TECHA RIVER BY THE "MAYAK PRODUCTION ASSOCIATION" IN 1949-1956) WERE INCLUDED IN THE STUDY. IT WAS ESTABLISHED THAT THE PROPORTION OF INDIVIDUALS WITH HYPERMETHYLATED BCL2 GENE PROMOTER AMONG THE EXPOSED PEOPLE WAS STATISTICALLY SIGNIFICANTLY HIGHER THAN IN THE CONTROL GROUP. THE PERCENTAGE OF METHYLATION OF THE ATM GENE PROMOTER WEAKLY POSITIVELY CORRELATED WITH DOSE AND AGE CHARACTERISTICS. DIFFERENCES IN THE FREQUENCY OF LYMPHOCYTE APOPTOSIS IN EXPOSED INDIVIDUALS WITH A HYPO- OR HYPERMETHYLATED ATM GENE PROMOTER WERE ALSO ESTABLISHED. THE DATA INDICATE THAT, IN THE LONG-TERM, AFTER CHRONIC LOW INTENSITY RADIATION EXPOSURE AT LOW AND MEDIUM DOSES, EPIGENETIC MODIFICATIONS OF THE GENOME OCCUR, WHICH ARE MANIFESTED AS CHANGES IN METHYLATION OF PROMOTER REGIONS OF BCL2 AND ATM GENES. 2022 12 2297 24 EPIGENETIC REGULATION OF ACUTE INFLAMMATORY PAIN. ACUTE PAIN IS ASSOCIATED WITH TISSUE DAMAGE, WHICH RESULTS IN THE RELEASE OF INFLAMMATORY MEDIATORS. RECENT STUDIES POINT TO THE INVOLVEMENT OF EPIGENETIC MECHANISMS (DNA METHYLATION) IN THE DEVELOPMENT OF PAIN. WE HAVE FOUND THAT DURING ACUTE INFLAMMATORY PAIN INDUCED BY THE APPLICATION OF 10% MUSTARD OIL ON THE TONGUES OF RATS, LEVELS OF DNMT3A AND 3B WERE ELEVATED MARKEDLY (36 AND 42 % RESPECTIVELY), WHEREAS THE LEVEL OF DNMT1 WAS NOT CHANGED SIGNIFICANTLY. PREVIOUS INJECTION OF XEFOCAM WITH 0,4 MG/KG DOSE DECREASED LEVELS OF DNMT3A AND 3B (25 AND 24% RESPECTIVELY). THE LEVEL OF DNMT1 WAS NOT CHANGED SIGNIFICANTLY COMPARED TO THE CONTROL GROUP. THE FINDINGS SUPPORT THE IDEA THAT INHIBITORS OF DNA-METHYLTRANSFERASES COULD BE USEFUL FOR PAIN MANAGEMENT. OUR DATA SUGGEST THAT NSAIDS (ALONE OR IN COMBINATION WITH DNMT INHIBITORS) MAY BE PROPOSED AS POSSIBLE EPIGENETIC REGULATORY AGENTS, WHICH MAY PLAY A ROLE IN EPIGENETIC MECHANISMS INDIRECTLY THROUGH ALTERING THE ACTIVITY OF INFLAMMATORY MEDIATORS INVOLVED IN PAIN DEVELOPMENT. 2014 13 2747 31 EXPRESSION ANALYSIS OF THE EPIGENETIC METHYLTRANSFERASES AND METHYL-CPG BINDING PROTEIN FAMILIES IN THE NORMAL B-CELL AND B-CELL CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). THE IMPORTANCE OF EPIGENETIC MODIFICATIONS IN CARCINOGENESIS HAS BEEN A SOURCE OF CONTROVERSY FOR SOME TIME. THERE IS LITTLE DOUBT THAT CHANGES IN GENOMIC HYPERMETHYLATION CONTRIBUTE TO THE SILENCING OF TUMOR SUPPRESSOR GENES. FURTHERMORE, RECENT STUDIES HAVE ALSO IDENTIFIED THE SIGNIFICANCE OF GENOMIC HYPOMETHYLATION ASSOCIATED WITH CHROMOSOMAL INSTABILITY AND TUMORIGENESIS. ONE OF THE MOST PERPLEXING QUESTIONS REGARDING EPIGENETIC MODIFICATIONS AND LEUKEMOGENESIS IS THE RELATIONSHIP WITH DNA METHYLTRANSFERASES (DNMT'S). THE PRIMARY FUNCTION OF THE DNMT ENZYMES IS TO METHYLATE GENOMIC DNA, WHEREAS THE METHYL-CPG BINDING DOMAIN PROTEINS (MBD) INTERPRET THIS METHYLATION SIGNAL AND REGULATE GENE EXPRESSION AND CHROMATIN BEHAVIOR. IN THIS STUDY WE ANALYSE THESE GENE FAMILIES BY QUANTITATIVE REAL-TIME PCR TO INVESTIGATE WHETHER EXPRESSION LEVELS AND THE B-CELL CHRONIC LYMPHOCYTIC LEUKEMIA (B-CLL) PHENOTYPE ARE ASSOCIATED. FURTHERMORE, GIVEN THE EPIGENETIC CROSSTALK BETWEEN GENOME STABILITY AND THE HISTONE CHROMATIN CODE WE HAVE ANALYSED EUKARYOTIC HISTONE METHYLTRANSFERASE (EU-HMTASEI). SURPRISINGLY, WE DID NOT OBSERVE SIGNIFICANT CHANGES IN DNMT1 EXPRESSION IN B-CLL CASES WHEN COMPARED TO NORMAL LYMPHOCYTES, REGARDLESS OF WHETHER WE NORMALISE AGAINST GAPDH OR PCNA AS REFERENCE STANDARDS. INDEED, EXPRESSION OF THE MAINTENANCE AND DE NOVO METHYLASES WERE INDEPENDENTLY REGULATED. OF PARTICULAR NOTE WAS THE SIGNIFICANT DOWN REGULATION OF DNMT3B. FURTHERMORE, WE OBSERVED A POSITIVE CORRELATION BETWEEN HMTASEI EXPRESSION LEVELS AND STAGE OF LEUKEMIA SUGGESTING THAT CHANGES IN THE METHYLATION PATTERNS IN B-CLL MAY REPRESENT DEREGULATION OF THE EPIGENETIC REPERTOIRE THAT ALSO INCLUDE THE METHYLATION DEPENDENT BINDING PROTEINS, MBD2 AND MECP2. WE ENVISAGE CHANGES IN THE EPIGENETIC PROGRAM ARE MULTIFACTORIAL IN NATURE AND POSTULATE THAT THE PREVALENT GENOMIC METHYLASES JUST ONE COMPONENT OF A LARGER EPIGENETIC REPERTOIRE. 2004 14 1519 34 DNA METHYLATION AT ATP11A CG11702988 IS A BIOMARKER OF LUNG DISEASE SEVERITY IN CYSTIC FIBROSIS: A LONGITUDINAL STUDY. CYSTIC FIBROSIS (CF) IS A CHRONIC GENETIC DISEASE THAT MAINLY AFFECTS THE RESPIRATORY AND GASTROINTESTINAL SYSTEMS. NO CURATIVE TREATMENTS ARE AVAILABLE, BUT THE FOLLOW-UP IN SPECIALIZED CENTERS HAS GREATLY IMPROVED THE PATIENT LIFE EXPECTANCY. ROBUST BIOMARKERS ARE REQUIRED TO MONITOR THE DISEASE, GUIDE TREATMENTS, STRATIFY PATIENTS, AND PROVIDE OUTCOME MEASURES IN CLINICAL TRIALS. IN THE PRESENT STUDY, WE OUTLINE A STRATEGY TO SELECT PUTATIVE DNA METHYLATION BIOMARKERS OF LUNG DISEASE SEVERITY IN CYSTIC FIBROSIS PATIENTS. IN THE DISCOVERY STEP, WE SELECTED SEVEN POTENTIAL BIOMARKERS USING A GENOME-WIDE DNA METHYLATION DATASET THAT WE GENERATED IN NASAL EPITHELIAL SAMPLES FROM THE METHYLCF COHORT. IN THE REPLICATION STEP, WE ASSESSED THE SAME BIOMARKERS USING SPUTUM CELL SAMPLES FROM THE METHYLBIOMARK COHORT. OF INTEREST, DNA METHYLATION AT THE CG11702988 SITE (ATP11A GENE) POSITIVELY CORRELATED WITH LUNG FUNCTION AND BMI, AND NEGATIVELY CORRELATED WITH LUNG DISEASE SEVERITY, P. AERUGINOSA CHRONIC INFECTION, AND THE NUMBER OF EXACERBATIONS. THESE RESULTS WERE REPLICATED IN PROSPECTIVE SPUTUM SAMPLES COLLECTED AT FOUR TIME POINTS WITHIN AN 18-MONTH PERIOD AND LONGITUDINALLY. TO CONCLUDE, (I) WE IDENTIFIED A DNA METHYLATION BIOMARKER THAT CORRELATES WITH CF SEVERITY, (II) WE PROVIDED A METHOD TO EASILY ASSESS THIS BIOMARKER, AND (III) WE CARRIED OUT THE FIRST LONGITUDINAL ANALYSIS OF DNA METHYLATION IN CF PATIENTS. THIS NEW EPIGENETIC BIOMARKER COULD BE USED TO STRATIFY CF PATIENTS IN CLINICAL TRIALS. 2021 15 1909 31 ENRICHMENT OF GENOMIC PATHWAYS BASED ON DIFFERENTIAL DNA METHYLATION PROFILES ASSOCIATED WITH CHRONIC MUSCULOSKELETAL PAIN IN OLDER ADULTS: AN EXPLORATORY STUDY. OUR STUDY AIMED TO IDENTIFY DIFFERENTIALLY METHYLATED CPGS/REGIONS AND THEIR ENRICHED GENOMIC PATHWAYS ASSOCIATED WITH UNDERLYING CHRONIC MUSCULOSKELETAL PAIN IN OLDER INDIVIDUALS. WE RECRUITED COGNITIVELY HEALTHY OLDER ADULTS WITH (N = 20) AND WITHOUT (N = 9) SELF-REPORTED MUSCULOSKELETAL PAIN AND COLLECTED DNA FROM PERIPHERAL BLOOD THAT WAS ANALYZED USING METHYLATIONEPIC ARRAYS. WE IDENTIFIED 31,739 HYPERMETHYLATED CPG AND 10,811 HYPOMETHYLATED CPG PROBES (PS