1 502 166 ASSOCIATION OF ARSENIC EXPOSURE WITH WHOLE BLOOD DNA METHYLATION: AN EPIGENOME-WIDE STUDY OF BANGLADESHI ADULTS. BACKGROUND: ARSENIC EXPOSURE AFFECTS [FORMULA: SEE TEXT] PEOPLE WORLDWIDE, INCLUDING [FORMULA: SEE TEXT] IN BANGLADESH. ARSENIC EXPOSURE INCREASES THE RISK OF CANCER AND OTHER CHRONIC DISEASES, AND ONE POTENTIAL MECHANISM OF ARSENIC TOXICITY IS EPIGENETIC DYSREGULATION. OBJECTIVE: WE ASSESSED ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND GENOME-WIDE DNA METHYLATION MEASURED AT BASELINE AMONG 396 BANGLADESHI ADULTS PARTICIPATING IN THE HEALTH EFFECTS OF ARSENIC LONGITUDINAL STUDY (HEALS) WHO WERE EXPOSED BY DRINKING NATURALLY CONTAMINATED WELL WATER. METHODS: METHYLATION IN WHOLE BLOOD DNA WAS MEASURED AT [FORMULA: SEE TEXT] USING THE ILLUMINA INFINIUMMETHYLATIONEPIC (EPIC) ARRAY. TO ASSESS ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND CPG METHYLATION, WE USED LINEAR REGRESSION MODELS ADJUSTED FOR COVARIATES AND SURROGATE VARIABLES (SVS) (CAPTURING UNKNOWN TECHNICAL AND BIOLOGIC FACTORS). WE ATTEMPTED REPLICATION AND CONDUCTED A META-ANALYSIS USING AN INDEPENDENT DATASET OF [FORMULA: SEE TEXT] FROM 400 BANGLADESHI INDIVIDUALS WITH ARSENICAL SKIN LESIONS. RESULTS: WE IDENTIFIED 34 CPGS ASSOCIATED WITH [FORMULA: SEE TEXT] CREATININE-ADJUSTED URINARY ARSENIC [[FORMULA: SEE TEXT]]. SIXTEEN OF THESE CPGS ANNOTATED TO THE [FORMULA: SEE TEXT] ARRAY, AND 10 ASSOCIATIONS WERE REPLICATED ([FORMULA: SEE TEXT]). THE TOP TWO CPGS ANNOTATED UPSTREAM OF THE ABR GENE (CG01912040, CG10003262 ). ALL URINARY ARSENIC-ASSOCIATED CPGS WERE ALSO ASSOCIATED WITH ARSENIC CONCENTRATION MEASURED IN DRINKING WATER ([FORMULA: SEE TEXT]). META-ANALYSIS ([FORMULA: SEE TEXT] SAMPLES) IDENTIFIED 221 URINARY ARSENIC-ASSOCIATED CPGS ([FORMULA: SEE TEXT]). THE ARSENIC-ASSOCIATED CPGS FROM THE META-ANALYSIS WERE ENRICHED IN NON-CPG ISLANDS AND SHORES ([FORMULA: SEE TEXT]) AND DEPLETED IN PROMOTER REGIONS ([FORMULA: SEE TEXT]). AMONG THE ARSENIC-ASSOCIATED CPGS ([FORMULA: SEE TEXT]), WE OBSERVED SIGNIFICANT ENRICHMENT OF GENES ANNOTATING TO THE REACTIVE OXYGEN SPECIES PATHWAY, INFLAMMATORY RESPONSE, AND TUMOR NECROSIS FACTOR [FORMULA: SEE TEXT] ([FORMULA: SEE TEXT]) SIGNALING VIA NUCLEAR FACTOR KAPPA-B ([FORMULA: SEE TEXT]) HALLMARKS ([FORMULA: SEE TEXT]). CONCLUSIONS: THE NOVEL AND REPLICABLE ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND DNA METHYLATION AT SPECIFIC CPGS OBSERVED IN THIS WORK SUGGEST THAT EPIGENETIC ALTERATIONS SHOULD BE FURTHER INVESTIGATED AS POTENTIAL MEDIATORS IN ARSENIC TOXICITY AND AS BIOMARKERS OF EXPOSURE AND EFFECT IN EXPOSED POPULATIONS. HTTPS://DOI.ORG/10.1289/EHP3849. 2019 2 6460 39 TIME TO RELAPSE IN CHRONIC LYMPHOCYTIC LEUKEMIA AND DNA-METHYLATION-BASED BIOLOGICAL AGE. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS A MATURE B CELL NEOPLASM WITH A PREDILECTION FOR OLDER INDIVIDUALS. WHILE PREVIOUS STUDIES HAVE IDENTIFIED EPIGENETIC SIGNATURES ASSOCIATED WITH CLL, WHETHER AGE-RELATED DNA METHYLATION CHANGES MODULATE CLL RELAPSE REMAINS ELUSIVE. IN THIS STUDY, WE EXAMINED THE ASSOCIATION BETWEEN EPIGENETIC AGE ACCELERATION AND TIME TO CLL RELAPSE IN A PUBLICLY AVAILABLE DATASET. DNA METHYLATION PROFILING OF 35 CLL PATIENTS PRIOR TO INITIATING CHEMOIMMUNOTHERAPY WAS PERFORMED USING THE INFINIUM HUMANMETHYLATION450 BEADCHIP. FOUR EPIGENETIC AGE ACCELERATION METRICS (INTRINSIC EPIGENETIC AGE ACCELERATION [IEAA], EXTRINSIC EPIGENETIC AGE ACCELERATION [EEAA], PHENOAGE ACCELERATION [PHENOAA], AND GRIMAGE ACCELERATION [GRIMAA]) WERE ESTIMATED FROM BLOOD DNA METHYLATION LEVELS. LINEAR, QUANTILE, AND LOGISTIC REGRESSION AND RECEIVER OPERATING CHARACTERISTIC CURVE ANALYSES WERE CONDUCTED TO ASSESS THE ASSOCIATION BETWEEN EACH EPIGENETIC AGE METRIC AND TIME TO CLL RELAPSE. EEAA (P = 0.011) AND PHENOAA (P = 0.046) WERE NEGATIVELY AND GRIMAA (P = 0.040) WAS POSITIVELY ASSOCIATED WITH TIME TO CLL RELAPSE. SIMULTANEOUS ASSESSMENT OF EEAA AND GRIMAA IN MALE PATIENTS DISTINGUISHED PATIENTS WHO RELAPSED EARLY FROM PATIENTS WHO RELAPSED LATER (P = 0.039). NO ASSOCIATIONS WERE OBSERVED WITH IEAA. THESE FINDINGS SUGGEST EPIGENETIC AGE ACCELERATION PRIOR TO CHEMOIMMUNOTHERAPY INITIATION IS ASSOCIATED WITH TIME TO CLL RELAPSE. OUR RESULTS PROVIDE NOVEL INSIGHT INTO THE ASSOCIATION BETWEEN AGE-RELATED DNA METHYLATION CHANGES AND CLL RELAPSE AND MAY SERVE HAS BIOMARKERS FOR TREATMENT RELAPSE, AND POTENTIALLY, TREATMENT SELECTION. 2023 3 3063 58 GENOME-WIDE DNA METHYLATION AND LONG-TERM AMBIENT AIR POLLUTION EXPOSURE IN KOREAN ADULTS. BACKGROUND: AMBIENT AIR POLLUTION IS ASSOCIATED WITH NUMEROUS ADVERSE HEALTH OUTCOMES, BUT THE UNDERLYING MECHANISMS ARE NOT WELL UNDERSTOOD; EPIGENETIC EFFECTS INCLUDING ALTERED DNA METHYLATION COULD PLAY A ROLE. TO EVALUATE ASSOCIATIONS OF LONG-TERM AIR POLLUTION EXPOSURE WITH DNA METHYLATION IN BLOOD, WE CONDUCTED AN EPIGENOME-WIDE ASSOCIATION STUDY IN A KOREAN CHRONIC OBSTRUCTIVE PULMONARY DISEASE COHORT (N = 100 INCLUDING 60 CASES) USING ILLUMINA'S INFINIUM HUMANMETHYLATION450K BEADCHIP. ANNUAL AVERAGE CONCENTRATIONS OF PARTICULATE MATTER 850,000 CPGS PER SAMPLE). BIOINFORMATIC ANALYSIS WAS PERFORMED USING R (MINFI, LIMMA, CHAMP, AND DMRCATE PACKAGES). RESULTS: DNA METHYLATION PROFILES IN CD8(+) T CELLS DIFFERENTIATE HEALTHY CONTROLS FROM PSORIASIS PATIENTS [397 DIFFERENTIALLY METHYLATED POSITIONS (DMPS); 9 DIFFERENTIALLY METHYLATED REGIONS (DMRS) WHEN >/=CPGS PER DMR WERE CONSIDERED; 2 DMRS FOR >/=10 CPGS]. FURTHERMORE, PATIENTS WITH SKIN PSORIASIS CAN BE DISCRIMINATED FROM PSA PATIENTS [1,861 DMPS, 20 DMRS (>/=5 CPGS PER REGION), 4 DMRS (>/=10 CPGS PER REGION)]. GENE ONTOLOGY (GO) ANALYSES CONSIDERING GENES WITH >/=1 DMP IN THEIR PROMOTER DELIVERED METHYLATION DEFECTS IN SKIN PSORIASIS AND PSA PRIMARILY AFFECTING THE BMP SIGNALING PATHWAY AND ENDOPEPTIDASE REGULATOR ACTIVITY, RESPECTIVELY. GO ANALYSIS OF GENES ASSOCIATED WITH DMRS BETWEEN SKIN PSORIASIS AND PSA DEMONSTRATED AN ENRICHMENT OF GABAERGIC NEURON AND CORTEX NEURON DEVELOPMENT PATHWAYS. TREATMENT WITH CYTOKINE BLOCKERS ASSOCIATED WITH DNA METHYLATION CHANGES [2,372 DMPS; 1,907 DMPS WITHIN PROMOTERS, 7 DMRS (>/=5 CPG PER REGIONS)] AFFECTING TRANSFORMING GROWTH FACTOR BETA RECEPTOR AND TRANSMEMBRANE RECEPTOR PROTEIN SERINE/THREONINE KINASE SIGNALING PATHWAYS. LASTLY, A METHYLATION SCORE INCLUDING TNF AND IL-17 PATHWAY ASSOCIATED DMPS INVERSE CORRELATES WITH SKIN DISEASE ACTIVITY SCORES (PASI). CONCLUSION: PATIENTS WITH SKIN PSORIASIS EXHIBIT DNA METHYLATION PATTERNS IN CD8(+) T CELLS THAT ALLOW DIFFERENTIATION FROM PSA PATIENTS AND HEALTHY INDIVIDUALS, AND REFLECT CLINICAL ACTIVITY OF SKIN DISEASE. THUS, DNA METHYLATION PROFILING PROMISES POTENTIAL AS DIAGNOSTIC AND PROGNOSTIC TOOL TO BE USED FOR MOLECULAR PATIENT STRATIFICATION TOWARD INDIVIDUALIZED TREATMENT. 2021 12 1910 47 ENRICHMENT OF GENOMIC PATHWAYS BASED ON DIFFERENTIAL DNA METHYLATION PROFILES ASSOCIATED WITH KNEE OSTEOARTHRITIS PAIN. OUR STUDY AIMED TO IDENTIFY DIFFERENTIALLY METHYLATED REGIONS (I.E., GENOMIC REGION WHERE MULTIPLE ADJACENT CPG SITES SHOW DIFFERENTIAL METHYLATION) AND THEIR ENRICHED GENOMIC PATHWAYS ASSOCIATED WITH KNEE OSTEOARTHRITIS PAIN (KOA). WE RECRUITED COGNITIVELY HEALTHY MIDDLE TO OLDER AGED (AGE 45-85) ADULTS WITH (N = 182) AND WITHOUT (N = 31) SELF-REPORTED KOA PAIN. WE ALSO EXTRACTED DNA FROM PERIPHERAL BLOOD THAT WAS ANALYZED USING METHYLATIONEPIC ARRAYS. THE R PACKAGE MINFI (ARYEE ET AL., 2014) WAS USED TO PERFORM METHYLATION DATA PREPROCESSING AND QUALITY CONTROL. TO INVESTIGATE BIOLOGICAL PATHWAYS IMPACTED BY DIFFERENTIAL METHYLATION, WE PERFORMED PATHWAY ENRICHMENT ANALYSIS USING INGENUITY PATHWAY ANALYSIS (IPA) TO IDENTIFY CANONICAL PATHWAYS AND UPSTREAM REGULATORS. ANNOTATED GENES WITHIN +/- 5 KB OF THE PUTATIVE DIFFERENTIALLY METHYLATED REGIONS (DMRS, P < 0.05) WERE SUBJECTED TO THE IPA ANALYSIS. THERE WAS NO SIGNIFICANT DIFFERENCE IN AGE, SEX, STUDY SITE BETWEEN NO PAIN AND PAIN GROUP (P > 0.05). NON-HISPANIC BLACK INDIVIDUALS WERE OVERREPRESENTED IN THE PAIN GROUP (P = 0.003). AT RAW P < 0.05 CUTOFF, WE IDENTIFIED A TOTAL OF 19,710 CPG PROBES, INCLUDING 13,951 HYPERMETHYLATED CPG PROBES, FOR WHICH DNA METHYLATION LEVEL WAS HIGHER IN THE GROUPS WITH HIGHEST PAIN GRADES. WE ALSO IDENTIFIED 5,759 HYPOMETHYLATED CPG PROBES FOR WHICH DNA METHYLATION LEVEL WAS LOWER IN THE PAIN GROUPS WITH HIGHER PAIN GRADES. IPA REVEALED THAT PAIN-RELATED DMRS WERE ENRICHED ACROSS MULTIPLE PATHWAYS AND UPSTREAM REGULATORS. THE TOP 10 CANONICAL PATHWAYS WERE LINKED TO CELLULAR SIGNALING PROCESSES RELATED TO IMMUNE RESPONSES (I.E., ANTIGEN PRESENTATION, PD-1, PD-L1 CANCER IMMUNOTHERAPY, B CELL DEVELOPMENT, IL-4 SIGNALING, TH1 AND TH2 ACTIVATION PATHWAY, AND PHAGOSOME MATURATION). MOREOVER, IN TERMS OF UPSTREAM REGULATORS, NDUFAF3 WAS THE MOST SIGNIFICANT (P = 8.6E-04) UPSTREAM REGULATOR. OUR FINDINGS SUPPORT PREVIOUS PRELIMINARY WORK SUGGESTING THE IMPORTANCE OF EPIGENETIC REGULATION OF THE IMMUNE SYSTEM IN KNEE PAIN AND THE NEED FOR FUTURE WORK TO UNDERSTAND THE EPIGENETIC CONTRIBUTIONS TO CHRONIC PAIN. 2022 13 2678 29 EVALUATION OF A PROGNOSTIC EPIGENETIC CLASSIFICATION SYSTEM IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS. BACKGROUND: METHYLATION AT 5 CPG SITES WAS PREVIOUSLY SHOWN TO CLASSIFY CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) INTO 3 PROGNOSTIC SUBGROUPS. HERE, WE AIMED TO VALIDATE THE MARKER SET IN AN ADDITIONAL COHORT AND TO EVALUATE ITS CLINICAL UTILITY FOR CLL PATIENT STRATIFICATION. METHODS: WE EVALUATED THIS EPIGENETIC MARKER SET IN 79 GERMAN PATIENTS USING BISULFITE TREATMENT FOLLOWED BY PYROSEQUENCING AND CLASSIFICATION USING A SUPPORT VECTOR MACHINE-LEARNING TOOL. RESULTS: THE N-CLL, I-CLL, AND M-CLL CLASSIFICATION WAS DETECTED IN 28 (35%), 10 (13%), AND 41 (51%) PATIENTS, RESPECTIVELY. EPIGENETIC GROUPING WAS ASSOCIATED WITH IGHV MUTATIONAL STATUS (P = 2 X 10(-12)), ISOLATED DEL13Q (P = 9 X 10(-6)), DEL17P (P = .015), COMPLEX KARYOTYPE (P = .005), VH-USAGE, AND CLINICAL OUTCOME AS TIME TO FIRST TREATMENT (P = 1.4 X 10(-12)) AND OVERALL SURVIVAL (P = .003). MULTIVARIATE COX REGRESSION ANALYSIS IDENTIFIED N-CLL AS A FACTOR FOR EARLIER TREATMENT HAZARD RATIO (HR), 6.3 (95% CONFIDENCE INTERVAL [CI] 2.4-16.4; P = .0002) COMPARED TO IGHV MUTATIONAL STATUS (HR 4.6, 95% CI 1.9-11.3, P = .0008). IN ADDITION, WHEN COMPARING THE PROGNOSTIC VALUE OF THE EPIGENETIC CLASSIFICATION SYSTEM WITH THE IGHV CLASSIFICATION, EPIGENETIC GROUPING PERFORMED BETTER COMPARED TO IGHV MUTATIONAL STATUS USING KAPLAN-MEIER ESTIMATION AND ALLOWED THE IDENTIFICATION OF A THIRD, INTERMEDIATE (I-CLL) GROUP. THUS, OUR STUDY CONFIRMED THE PROGNOSTIC VALUE OF THE EPIGENETIC MARKER SET FOR PATIENT STRATIFICATION IN ROUTINE CLINICAL DIAGNOSTICS. 2022 14 3501 44 IDENTIFICATION OF POTENTIAL BIOMARKERS FOR SYSTEMIC LUPUS ERYTHEMATOSUS BY INTEGRATED ANALYSIS OF GENE EXPRESSION AND METHYLATION DATA. INTRODUCTION: SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS A HETEROGENEOUS AND CHRONIC AUTOIMMUNE DISEASE. ABERRANT DNA METHYLATION OCCURS DURING VARIOUS PROCESSES OF SLE DEVELOPMENT REGULATING THE MRNA EXPRESSION OF INTERRELATED GENES. THIS STUDY AIMS TO SCREEN POTENTIAL DNA METHYLATION MARKERS FOR SLE. METHODS: GENE EXPRESSION AND METHYLATION DATASETS WERE DOWNLOADED FROM THE GENE EXPRESSION OMNIBUS (GEO) DATABASE. DIFFERENTIALLY EXPRESSED GENES (DEGS) BETWEEN SLE PATIENTS AND HEALTHY CONTROLS WERE SCREENED USING THE LIMMA R PACKAGE, AND DIFFERENTIALLY METHYLATED POSITIONS (DMPS) AND REGIONS (DMRS) WERE IDENTIFIED USING DMPFINDER AND BUMPHUNTER (MINFI). ADDITIONALLY, THE DNA METHYLATION MARKERS TO DISTINGUISH SLE PATIENTS FROM HEALTHY CONTROLS WERE EXPLORED THROUGH RECEIVER OPERATING CHARACTERISTIC (ROC) CURVES AND LOGISTIC REGRESSION ANALYSES. FINALLY, WE VALIDATED THE RESULTS OF THE BIOINFORMATIC ANALYSIS BY PYROSEQUENCING. RESULTS: IN TOTAL, 91 DEGS, 90,092 DMPS, 15 DMRS, AND 13 DMR-ASSOCIATED GENES WERE IDENTIFIED. THROUGH THE INTEGRATIVE ANALYSIS OF DEG- AND DMR-ASSOCIATED GENES, WE IDENTIFIED FIVE TYPE I INTERFERON (IFN)-RELATED GENES AS KEY EPIGENETIC-DRIVEN GENES IN SLE. GO ENRICHMENT ANALYSIS SHOWED THAT THE FIVE SLE-ASSOCIATED EPIGENETIC-DRIVEN GENES WERE MAINLY ENRICHED IN THE TYPE I IFN SIGNALING PATHWAY INVOLVED IN IMMUNE RESPONSE AND DEFENSE RESPONSE TO VIRUS. MOREOVER, WE IDENTIFIED TWO SLE-SPECIFIC DNA METHYLATION MARKERS, THREE SLE WITHOUT LUPUS NEPHRITIS (SLE-LN(-))-SPECIFIC DNA METHYLATION MARKERS, AND TWO SLE WITH LUPUS NEPHRITIS (SLE-LN(+))-SPECIFIC DNA METHYLATION MARKERS BY STEPWISE LOGISTIC REGRESSION. CONCLUSIONS: OVERALL, OUR STUDY DEMONSTRATES POTENTIAL DNA METHYLATION MARKERS OF SLE, SLE-LN(-), AND SLE-LN(+), WHICH MAY HELP THE DIAGNOSIS, BOOST THE DEVELOPMENT OF NEW EPIGENETIC THERAPY, AND CONTRIBUTE TO INDIVIDUALIZED TREATMENT. KEY POINTS * THIS STUDY IDENTIFIED FIVE TYPE I IFN-RELATED GENES AS KEY EPIGENETIC-DRIVEN GENES IN SLE, WHICH SUPPORT THE IMPORTANCE OF THE TYPE I IFN PATHWAY IN THE PATHOGENESIS OF SLE * WE IDENTIFIED NOVEL DNA METHYLATION BIOMARKERS IN SLE, SLE-LN-, AND SLE-LN+ BY A COMPREHENSIVE ANALYSIS OF BIOINFORMATICS METHODS AND EXECUTED EXPERIMENTAL VALIDATION, AND BINARY LOGISTIC REGRESSION ANALYSIS SHOWED THAT THEY HAVE EXCELLENT POTENTIAL * THESE RESULTS MAY PROVIDE NEW INSIGHTS INTO THE BIOLOGICAL MECHANISMS OF SLE, AND IDENTIFY RELIABLE BIOMARKERS FOR SLE, SLE-LN-, AND SLE-LN+, WHICH MAY CONTRIBUTE TO DIAGNOSIS AND INDIVIDUALIZED TREATMENT. 2023 15 2079 46 EPIGENETIC DNA METHYLATION CHANGES ASSOCIATED WITH HEADACHE CHRONIFICATION: A RETROSPECTIVE CASE-CONTROL STUDY. BACKGROUND THE BIOLOGICAL MECHANISMS OF HEADACHE CHRONIFICATION ARE POORLY UNDERSTOOD. WE AIMED TO IDENTIFY CHANGES IN DNA METHYLATION ASSOCIATED WITH THE TRANSFORMATION FROM EPISODIC TO CHRONIC HEADACHE. METHODS PARTICIPANTS WERE RECRUITED FROM THE POPULATION-BASED NORWEGIAN HUNT STUDY. THIRTY-SIX FEMALE HEADACHE PATIENTS WHO TRANSFORMED FROM EPISODIC TO CHRONIC HEADACHE BETWEEN BASELINE AND FOLLOW-UP 11 YEARS LATER WERE MATCHED AGAINST 35 CONTROLS WITH EPISODIC HEADACHE. DNA METHYLATION WAS QUANTIFIED AT 485,000 CPG SITES, AND CHANGES IN METHYLATION LEVEL AT THESE SITES WERE COMPARED BETWEEN CASES AND CONTROLS BY LINEAR REGRESSION ANALYSIS. DATA WERE ANALYZED IN TWO STAGES (STAGES 1 AND 2) AND IN A COMBINED META-ANALYSIS. RESULTS NONE OF THE TOP 20 CPG SITES IDENTIFIED IN STAGE 1 REPLICATED IN STAGE 2 AFTER MULTIPLE TESTING CORRECTION. IN THE COMBINED META-ANALYSIS THE STRONGEST ASSOCIATED CPG SITES WERE RELATED TO SH2D5 AND NPTX2, TWO BRAIN-EXPRESSED GENES INVOLVED IN THE REGULATION OF SYNAPTIC PLASTICITY. FUNCTIONAL ENRICHMENT ANALYSIS POINTED TO PROCESSES INCLUDING CALCIUM ION BINDING AND ESTROGEN RECEPTOR PATHWAYS. CONCLUSION IN THIS FIRST GENOME-WIDE STUDY OF DNA METHYLATION IN HEADACHE CHRONIFICATION SEVERAL POTENTIALLY IMPLICATED LOCI AND PROCESSES WERE IDENTIFIED. THE STUDY EXEMPLIFIES THE USE OF PROSPECTIVELY COLLECTED POPULATION COHORTS TO SEARCH FOR EPIGENETIC MECHANISMS OF DISEASE. 2018 16 1581 34 DNA METHYLATION PROFILES IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS TREATED WITH CHEMOIMMUNOTHERAPY. BACKGROUND: IN ORDER TO GAIN INSIGHT INTO THE CONTRIBUTION OF DNA METHYLATION TO DISEASE PROGRESSION OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), USING 450K ILLUMINA ARRAYS, WE DETERMINED THE DNA METHYLATION PROFILES IN PAIRED PRE-TREATMENT/RELAPSE SAMPLES FROM 34 CLL PATIENTS TREATED WITH CHEMOIMMUNOTHERAPY, MOSTLY (N = 31) WITH THE FLUDARABINE-CYCLOPHOSPHAMIDE-RITUXIMAB (FCR) REGIMEN. RESULTS: THE EXTENT OF IDENTIFIED CHANGES IN CLL CELLS VERSUS MEMORY B CELLS FROM HEALTHY DONORS WAS TERMED "EPIGENETIC BURDEN" (EB) WHEREAS THE NUMBER OF CHANGES BETWEEN THE PRE-TREATMENT VERSUS THE RELAPSE SAMPLE WAS TERMED "RELAPSE CHANGES" (RC). SIGNIFICANT (P < 0.05) ASSOCIATIONS WERE IDENTIFIED BETWEEN (I) HIGH EB AND SHORT TIME-TO-FIRST-TREATMENT (TTFT); AND, (II) FEW RCS AND SHORT TIME-TO-RELAPSE. BOTH THE EB AND THE RC CLUSTERED IN SPECIFIC GENOMIC REGIONS AND CHROMATIN STATES, INCLUDING REGULATORY REGIONS CONTAINING BINDING SITES OF TRANSCRIPTION FACTORS IMPLICATED IN B CELL AND CLL BIOLOGY. CONCLUSIONS: OVERALL, WE SHOW THAT DNA METHYLATION IN CLL FOLLOWS DIFFERENT DYNAMICS IN RESPONSE TO CHEMOIMMUNOTHERAPY. THESE EPIGENETIC ALTERATIONS WERE LINKED WITH SPECIFIC CLINICAL AND BIOLOGICAL FEATURES. 2019 17 1586 46 DNA METHYLATION PROFILING IDENTIFIES EPIGENETIC DIFFERENCES BETWEEN EARLY VERSUS LATE STAGES OF DIABETIC CHRONIC KIDNEY DISEASE. BACKGROUND: WE INVESTIGATED A CROSS-SECTIONAL EPIGENOME-WIDE ASSOCIATION STUDY OF PATIENTS WITH EARLY AND LATE DIABETES-ASSOCIATED CHRONIC KIDNEY DISEASE (CKD) TO IDENTIFY POSSIBLE EPIGENETIC DIFFERENCES BETWEEN THE TWO GROUPS AS WELL AS CHANGES IN METHYLATION ACROSS ALL STAGES OF DIABETIC CKD. WE ALSO EVALUATED THE POTENTIAL OF USING A PANEL OF IDENTIFIED 5'-C-PHOSPHATE-G-3' (CPG) SITES FROM THIS COHORT TO PREDICT THE PROGRESSION OF DIABETIC CKD. METHODS: THIS CROSS-SECTIONAL STUDY RECRUITED 119 ADULTS. DNA WAS EXTRACTED FROM BLOOD USING THE QIAGEN QIAAMPDNA MINI SPIN KIT. GENOME-WIDE METHYLATION ANALYSIS WAS PERFORMED USING ILLUMINA INFINIUM METHYLATIONEPIC BEADCHIPS (HM850K). INTENSITY DATA FILES WERE PROCESSED AND ANALYSED USING THE MINFI AND MISSMETHYL PACKAGES FOR R. WE EXAMINED THE DEGREE OF METHYLATION OF CPG SITES IN EARLY VERSUS LATE DIABETIC CKD PATIENTS FOR CPG SITES WITH AN UNADJUSTED P-VALUE <0.01 AND AN ABSOLUTE CHANGE IN METHYLATION OF 5% (N = 239 CPG SITES). RESULTS: HIERARCHICAL CLUSTERING OF THE 239 CPG SITES LARGELY SEPARATED THE TWO GROUPS. A HEAT MAP FOR ALL 239 CPG SITES DEMONSTRATED DISTINCT METHYLATION PATTERNS IN THE EARLY VERSUS LATE GROUPS, WITH CPG SITES SHOWING EVIDENCE OF PROGRESSIVE CHANGE. BASED ON OUR DIFFERENTIALLY METHYLATED REGION (DMR) ANALYSIS OF THE 239 CPG SITES, WE HIGHLIGHTED TWO DMRS, NAMELY THE CYSTEINE-RICH SECRETORY PROTEIN 2 (CRISP2) AND PIWI-LIKE RNA-MEDIATED GENE SILENCING 1 (PIWIL1) GENES. THE BEST PREDICTABILITY FOR THE TWO GROUPS INVOLVED A RECEIVER OPERATING CHARACTERISTICS CURVE OF EIGHT CPG SITES ALONE AND ACHIEVED AN AREA UNDER THE CURVE OF 0.976. CONCLUSIONS: WE HAVE IDENTIFIED DISTINCT DNA METHYLATION PATTERNS BETWEEN EARLY AND LATE DIABETIC CKD PATIENTS AS WELL AS DEMONSTRATED NOVEL FINDINGS OF POTENTIAL PROGRESSIVE METHYLATION CHANGES ACROSS ALL STAGES (1-5) OF DIABETIC CKD AT SPECIFIC CPG SITES. WE HAVE ALSO IDENTIFIED ASSOCIATED GENES CRISP2 AND PIWIL1, WHICH MAY HAVE THE POTENTIAL TO ACT AS STAGE-SPECIFIC DIABETES-ASSOCIATED CKD MARKERS, AND SHOWED THAT THE USE OF A PANEL OF EIGHT IDENTIFIED CPG SITES ALONE HELPS TO INCREASE THE PREDICTABILITY FOR THE TWO GROUPS. 2021 18 2632 59 EPIGENOME-WIDE DNA METHYLATION AND PESTICIDE USE IN THE AGRICULTURAL LUNG HEALTH STUDY. BACKGROUND: PESTICIDE EXPOSURE IS ASSOCIATED WITH MANY LONG-TERM HEALTH OUTCOMES; THE POTENTIAL UNDERLYING MECHANISMS ARE NOT WELL ESTABLISHED FOR MOST ASSOCIATIONS. EPIGENETIC MODIFICATIONS, SUCH AS DNA METHYLATION, MAY CONTRIBUTE. INDIVIDUAL PESTICIDES MAY BE ASSOCIATED WITH SPECIFIC DNA METHYLATION PATTERNS BUT NO EPIGENOME-WIDE ASSOCIATION STUDY (EWAS) HAS EVALUATED METHYLATION IN RELATION TO INDIVIDUAL PESTICIDES. OBJECTIVES: WE CONDUCTED AN EWAS OF DNA METHYLATION IN RELATION TO SEVERAL PESTICIDE ACTIVE INGREDIENTS. METHODS: THE AGRICULTURAL LUNG HEALTH STUDY IS A CASE-CONTROL STUDY OF ASTHMA, NESTED WITHIN THE AGRICULTURAL HEALTH STUDY. WE ANALYZED BLOOD DNA METHYLATION MEASURED USING ILLUMINA'S EPIC ARRAY IN 1,170 MALE FARMERS OF EUROPEAN ANCESTRY. FOR PESTICIDES STILL ON THE MARKET AT BLOOD COLLECTION (2009-2013), WE EVALUATED NINE ACTIVE INGREDIENTS FOR WHICH AT LEAST 30 PARTICIPANTS REPORTED PAST AND CURRENT (WITHIN THE LAST 12 MONTHS) USE, AS WELL AS SEVEN BANNED ORGANOCHLORINES WITH AT LEAST 30 PARTICIPANTS REPORTING PAST USE. WE USED ROBUST LINEAR REGRESSION TO COMPARE METHYLATION AT INDIVIDUAL C-PHOSPHATE-G SITES (CPGS) AMONG USERS OF A SPECIFIC PESTICIDE TO NEVER USERS. RESULTS: USING FAMILY-WISE ERROR RATE (P < 9 X 10-8) OR FALSE-DISCOVERY RATE (FDR < 0.05), WE IDENTIFIED 162 DIFFERENTIALLY METHYLATED CPGS ACROSS 8 OF 9 CURRENTLY MARKETED ACTIVE INGREDIENTS (ACETOCHLOR, ATRAZINE, DICAMBA, GLYPHOSATE, MALATHION, METOLACHLOR, MESOTRIONE, AND PICLORAM) AND ONE BANNED ORGANOCHLORINE (HEPTACHLOR). DIFFERENTIALLY METHYLATED CPGS WERE UNIQUE TO EACH ACTIVE INGREDIENT, AND A DOSE-RESPONSE RELATIONSHIP WITH LIFETIME DAYS OF USE WAS OBSERVED FOR MOST. SIGNIFICANT CPGS WERE ENRICHED FOR TRANSCRIPTION MOTIFS AND 28% OF CPGS WERE ASSOCIATED WITH WHOLE BLOOD CIS-GENE EXPRESSION, SUPPORTING FUNCTIONAL EFFECTS OF FINDINGS. WE CORROBORATED A PREVIOUSLY REPORTED ASSOCIATION BETWEEN DICHLORODIPHENYLTRICHLOROETHANE (BANNED IN THE UNITED STATES IN 1972) AND EPIGENETIC AGE ACCELERATION. DISCUSSION: WE IDENTIFIED DIFFERENTIAL METHYLATION FOR SEVERAL ACTIVE INGREDIENTS IN MALE FARMERS OF EUROPEAN ANCESTRY. THESE MAY SERVE AS BIOMARKERS OF CHRONIC EXPOSURE AND COULD INFORM MECHANISMS OF LONG-TERM HEALTH OUTCOMES FROM PESTICIDE EXPOSURE. HTTPS://DOI.ORG/10.1289/EHP8928. 2021 19 93 39 A PILOT STUDY OF PERIPHERAL BLOOD DNA METHYLATION MODELS AS PREDICTORS OF KNEE OSTEOARTHRITIS RADIOGRAPHIC PROGRESSION: DATA FROM THE OSTEOARTHRITIS INITIATIVE (OAI). KNEE OSTEOARTHRITIS (OA) IS A LEADING CAUSE OF CHRONIC DISABILITY WORLDWIDE, BUT NO DIAGNOSTIC OR PROGNOSTIC BIOMARKERS ARE AVAILABLE. INCREASING EVIDENCE SUPPORTS EPIGENETIC DYSREGULATION AS A CONTRIBUTOR TO OA PATHOGENESIS. IN THIS PILOT STUDY, WE INVESTIGATED EPIGENETIC PATTERNS IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) AS MODELS TO PREDICT FUTURE RADIOGRAPHIC PROGRESSION IN OA PATIENTS ENROLLED IN THE LONGITUDINAL OSTEOARTHRITIS INITIATIVE (OAI) STUDY. PBMC DNA WAS ANALYZED FROM BASELINE OAI VISITS IN 58 FUTURE RADIOGRAPHIC PROGRESSORS (JOINT SPACE NARROWING AT 24 MONTHS, SUSTAINED AT 48 MONTHS) COMPARED TO 58 NON-PROGRESSORS. DNA METHYLATION WAS QUANTIFIED VIA ILLUMINA MICROARRAYS AND BETA- AND M-VALUES WERE USED TO GENERATE LINEAR CLASSIFICATION MODELS. DATA WERE RANDOMLY SPLIT INTO A 60% DEVELOPMENT AND 40% VALIDATION SUBSETS, MODELS DEVELOPED AND TESTED, AND CROSS-VALIDATED IN A TOTAL OF 40 CYCLES. M-VALUE BASED MODELS OUTPERFORMED BETA-VALUE BASED MODELS (ROC-AUC 0.81 +/- 0.01 VS. 0.73 +/- 0.02, MEAN +/- SEM, COMPARISON P = 0.002), WITH A MEAN CLASSIFICATION ACCURACY OF 73 +/- 1% (MEAN +/- SEM) FOR M- AND 69 +/- 1% FOR BETA-BASED MODELS. ADJUSTING FOR COVARIATES DID NOT SIGNIFICANTLY ALTER MODEL PERFORMANCE. OUR FINDINGS SUGGEST THAT PBMC DNA METHYLATION-BASED MODELS MAY BE USEFUL AS BIOMARKERS OF OA PROGRESSION AND WARRANT ADDITIONAL EVALUATION IN LARGER PATIENT COHORTS. 2019 20 5463 49 RESIDENTIAL PM(2.5) EXPOSURE AND THE NASAL METHYLOME IN CHILDREN. RATIONALE: PM(2.5-)INDUCED ADVERSE EFFECTS ON RESPIRATORY HEALTH MAY BE DRIVEN BY EPIGENETIC MODIFICATIONS IN AIRWAY CELLS. THE POTENTIAL IMPACT OF EXPOSURE DURATION ON EPIGENETIC ALTERATIONS IN THE AIRWAYS IS NOT YET KNOWN. OBJECTIVES: WE AIMED TO STUDY ASSOCIATIONS OF FINE PARTICULATE MATTER PM(2.5) EXPOSURE WITH DNA METHYLATION IN NASAL CELLS. METHODS: WE CONDUCTED NASAL EPIGENOME-WIDE ASSOCIATION ANALYSES WITHIN 503 CHILDREN FROM PROJECT VIVA (MEAN AGE 12.9 Y), AND EXAMINED VARIOUS EXPOSURE DURATIONS (1-DAY, 1-WEEK, 1-MONTH, 3-MONTHS AND 1-YEAR) PRIOR TO NASAL SAMPLING. WE USED RESIDENTIAL ADDRESSES TO ESTIMATE AVERAGE DAILY PM(2.5) AT 1 KM RESOLUTION. WE COLLECTED NASAL SWABS FROM THE ANTERIOR NARES AND MEASURED DNA METHYLATION (DNAM) USING THE ILLUMINA METHYLATIONEPIC BEADCHIP. WE TESTED 719,075 HIGH QUALITY AUTOSOMAL CPGS USING CPG-BY-CPG AND REGIONAL DNAM ANALYSES CONTROLLING FOR MULTIPLE COMPARISONS, AND ADJUSTED FOR MATERNAL EDUCATION, HOUSEHOLD SMOKERS, CHILD SEX, RACE/ETHNICITY, BMI Z-SCORE, AGE, SEASON AT SAMPLE COLLECTION AND CELL-TYPE HETEROGENEITY. WE FURTHER CORRECTED FOR BIAS AND GENOMIC INFLATION. WE TESTED FOR REPLICATION IN A COHORT FROM THE NETHERLANDS (PIAMA). RESULTS: IN ADJUSTED ANALYSES, WE FOUND 362 CPGS ASSOCIATED WITH 1-YEAR PM(2.5) (FDR < 0.05), 20 CPGS PASSING BONFERRONI CORRECTION (P < 7.0X10(-8)) AND 10 DIFFERENTIALLY METHYLATED REGIONS (DMRS). IN 445 PIAMA PARTICIPANTS (MEAN AGE 16.3 YEARS) 11 OF 203 AVAILABLE CPGS REPLICATED AT P < 0.05. WE OBSERVED DIFFERENTIAL DNAM AT/NEAR GENES IMPLICATED IN CELL CYCLE, IMMUNE AND INFLAMMATORY RESPONSES. THERE WERE NO CPGS OR REGIONS ASSOCIATED WITH PM(2.5) LEVELS AT 1-DAY, 1-WEEK, OR 1-MONTH PRIOR TO SAMPLE COLLECTION, ALTHOUGH 2 CPGS WERE ASSOCIATED WITH PAST 3-MONTH PM(2.5). CONCLUSION: WE OBSERVED WIDE-SPREAD DNAM VARIABILITY ASSOCIATED WITH AVERAGE PAST YEAR PM(2.5) EXPOSURE BUT WE DID NOT DETECT ASSOCIATIONS WITH SHORTER-TERM EXPOSURE. OUR RESULTS SUGGEST THAT NASAL DNAM MARKS REFLECT CHRONIC AIR POLLUTION EXPOSURE. 2021