1 1132 128 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 2 5236 35 PROFILING NON-CODING RNA LEVELS WITH CLINICAL CLASSIFIERS IN PEDIATRIC CROHN'S DISEASE. BACKGROUND: CROHN'S DISEASE (CD) IS A HERITABLE CHRONIC INFLAMMATORY DISORDER. NON-CODING RNAS (NCRNAS) PLAY AN IMPORTANT ROLE IN EPIGENETIC REGULATION BY AFFECTING GENE EXPRESSION, BUT CAN ALSO DIRECTLY AFFECT PROTEIN FUNCTION, THUS HAVING A SUBSTANTIAL IMPACT ON BIOLOGICAL PROCESSES. WE INVESTIGATED WHETHER NON-CODING RNAS (NCRNA) AT DIAGNOSIS ARE DYSREGULATED DURING CD AT DIFFERENT CD LOCATIONS AND FUTURE DISEASE BEHAVIORS TO DETERMINE IF NCRNA SIGNATURES CAN SERVE AS AN INDEX TO OUTCOMES. METHODS: USING SUBJECTS BELONGING TO THE RISK COHORT, WE ANALYZED NCRNA FROM THE ILEAL BIOPSIES OF 345 CD AND 71 NON-IBD CONTROLS, AND NCRNA FROM RECTAL BIOPSIES OF 329 CD AND 61 NON-IBD CONTROLS. SEQUENCE ALIGNMENT WAS DONE (STAR PACKAGE) USING HUMAN GENOME VERSION 38 (HG38) AS REFERENCE PANEL. THE DIFFERENTIAL EXPRESSION (DE) ANALYSIS WAS PERFORMED WITH EDGER PACKAGE AND DE NCRNAS WERE IDENTIFIED WITH A THRESHOLD OF FOLD CHANGE (FC) > 2 AND FDR < 0.05 AFTER MULTIPLE TEST CORRECTIONS. RESULTS: IN TOTAL, WE IDENTIFIED 130 CD SPECIFIC DE NCRNAS (89 IN ILEUM AND 41 IN RECTUM) WHEN COMPARED TO NON-IBD CONTROLS. SIMILARLY, 35 DE NCRNAS WERE IDENTIFIED BETWEEN B1 AND B2 IN ILEUM, WHEREAS NO DIFFERENCES AMONG CD DISEASE BEHAVIORS WERE NOTICED IN RECTUM. WE ALSO FOUND INFLAMMATION SPECIFIC NCRNAS BETWEEN INFLAMED AND NON-INFLAMED GROUPS IN ILEAL BIOPSIES. OVERALL, WE OBSERVED THAT EXPRESSION OF MIR1244-2, MIR1244-3, MIR1244-4, AND RN7SL2 WERE INCREASED DURING CD, REGARDLESS OF DISEASE BEHAVIOR, LOCATION, OR INFLAMMATORY STATUS. LASTLY, WE TESTED NCRNA EXPRESSION AT BASELINE AS POTENTIAL TOOL TO PREDICT THE DISEASE STATUS, DISEASE BEHAVIORS AND DISEASE INFLAMMATION AT 3-YEAR FOLLOW UP. CONCLUSIONS: WE HAVE IDENTIFIED NCRNAS THAT ARE SPECIFIC TO DISEASE LOCATION, DISEASE BEHAVIOR, AND DISEASE INFLAMMATION IN CD. BOTH ILEAL AND RECTAL SPECIFIC NCRNA ARE CHANGING OVER THE COURSE OF CD, SPECIFICALLY DURING THE DISEASE PROGRESSION IN THE INTESTINAL MUCOSA. COLLECTIVELY, OUR FINDINGS SHOW CHANGES IN NCRNA DURING CD AND MAY HAVE A CLINICAL UTILITY IN EARLY IDENTIFICATION AND CHARACTERIZATION OF DISEASE PROGRESSION. 2021 3 1433 47 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 4 3989 38 LONGITUDINAL ANALYSIS OF BLOOD DNA METHYLATION IDENTIFIES MECHANISMS OF RESPONSE TO TUMOR NECROSIS FACTOR INHIBITOR THERAPY IN RHEUMATOID ARTHRITIS. BACKGROUND: RHEUMATOID ARTHRITIS (RA) IS A CHRONIC, IMMUNE-MEDIATED INFLAMMATORY DISEASE OF THE JOINTS THAT HAS BEEN ASSOCIATED WITH VARIATION IN THE PERIPHERAL BLOOD METHYLOME. IN THIS STUDY, WE AIM TO IDENTIFY EPIGENETIC VARIATION THAT IS ASSOCIATED WITH THE RESPONSE TO TUMOR NECROSIS FACTOR INHIBITOR (TNFI) THERAPY. METHODS: PERIPHERAL BLOOD GENOME-WIDE DNA METHYLATION PROFILES WERE ANALYZED IN A DISCOVERY COHORT OF 62 RA PATIENTS AT BASELINE AND AT WEEK 12 OF TNFI THERAPY. DNA METHYLATION OF INDIVIDUAL CPG SITES AND ENRICHMENT OF BIOLOGICAL PATHWAYS WERE EVALUATED FOR THEIR ASSOCIATION WITH DRUG RESPONSE. USING A NOVEL CELL DECONVOLUTION APPROACH, ALTERED DNA METHYLATION ASSOCIATED WITH TNFI RESPONSE WAS ALSO TESTED IN THE SIX MAIN IMMUNE CELL TYPES IN BLOOD. VALIDATION OF THE RESULTS WAS PERFORMED IN AN INDEPENDENT LONGITUDINAL COHORT OF 60 RA PATIENTS. FINDINGS: TREATMENT WITH TNFI WAS ASSOCIATED WITH SIGNIFICANT LONGITUDINAL PERIPHERAL BLOOD METHYLATION CHANGES IN BIOLOGICAL PATHWAYS RELATED TO RA (FDR<0.05). 139 BIOLOGICAL FUNCTIONS WERE MODIFIED BY THERAPY, WITH METHYLATION LEVELS CHANGING SYSTEMATICALLY TOWARDS A SIGNATURE SIMILAR TO THAT OF HEALTHY CONTROLS. DIFFERENCES IN THE METHYLATION PROFILE OF T CELL ACTIVATION AND DIFFERENTIATION, GTPASE-MEDIATED SIGNALING, AND ACTIN FILAMENT ORGANIZATION PATHWAYS WERE ASSOCIATED WITH THE CLINICAL RESPONSE TO THERAPY. CELL TYPE DECONVOLUTION ANALYSIS IDENTIFIED CPG SITES IN CD4+T, NK, NEUTROPHILS AND MONOCYTES THAT WERE SIGNIFICANTLY ASSOCIATED WITH THE RESPONSE TO TNFI. INTERPRETATION: OUR RESULTS SHOW THAT TREATMENT WITH TNFI RESTORES HOMEOSTATIC BLOOD METHYLATION IN RA. THE CLINICAL RESPONSE TO TNFI IS ASSOCIATED TO METHYLATION VARIATION IN SPECIFIC BIOLOGICAL PATHWAYS, AND IT INVOLVES CELLS FROM BOTH THE INNATE AND ADAPTIVE IMMUNE SYSTEMS. FUNDING: THE INSTITUTO DE SALUD CARLOS III. 2022 5 5243 34 PROGNOSTIC IMPACT OF EPIGENETIC CLASSIFICATION IN CHRONIC LYMPHOCYTIC LEUKEMIA: THE CASE OF SUBSET #2. BASED ON THE METHYLATION STATUS OF 5 SINGLE CPG SITES, A NOVEL EPIGENETIC CLASSIFICATION OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) WAS RECENTLY PROPOSED, CLASSIFYING CLL PATIENTS INTO 3 CLINICO-BIOLOGICAL SUBGROUPS WITH DIFFERENT OUTCOME, TERMED MEMORY LIKE CLL (M-CLL), NAIVE LIKE CLL (N-CLL), AND A THIRD INTERMEDIATE CLL SUBGROUP (I-CLL). WHILE M-CLL AND N-CLL PATIENTS AT LARGE CORRESPONDED TO PATIENTS CARRYING MUTATED AND UNMUTATED IGHV GENES, RESPECTIVELY, LIMITED INFORMATION EXISTS REGARDING THE LESS DEFINED I-CLL GROUP. USING PYROSEQUENCING, WE INVESTIGATED THE PROGNOSTIC IMPACT OF THE PROPOSED 5 CPG SIGNATURE IN A WELL-CHARACTERIZED CLL COHORT (135 CASES), INCLUDING IGHV-MUTATED AND UNMUTATED PATIENTS AS WELL AS CLINICALLY AGGRESSIVE STEREOTYPED SUBSET #2 PATIENTS. OVERALL, WE CONFIRMED THE SIGNATURE'S ASSOCIATION WITH ESTABLISHED PROGNOSTIC MARKERS. MOREOVER, IN THE PRESENCE OF THE IGHV MUTATIONAL STATUS, THE EPIGENETIC SIGNATURE REMAINED INDEPENDENTLY ASSOCIATED WITH BOTH TIME-TO-FIRST-TREATMENT AND OVERALL SURVIVAL IN MULTIVARIATE ANALYSES. AS A PRIME FINDING, WE OBSERVED THAT SUBSET #2 PATIENTS WERE PREDOMINANTLY CLASSIFIED AS I-CLL, PROBABLY REFLECTING THEIR BORDERLINE IGHV MUTATIONAL STATUS (97-99% GERMLINE IDENTITY), THOUGH HAVING A SIMILARLY POOR PROGNOSIS AS N-CLL PATIENTS. IN SUMMARY, WE VALIDATED THE EPIGENETIC CLASSIFIER AS AN INDEPENDENT FACTOR IN CLL PROGNOSTICATION AND PROVIDE FURTHER EVIDENCE THAT SUBSET #2 IS A MEMBER OF THE I-CLL GROUP, HENCE SUPPORTING THE EXISTENCE OF A THIRD, INTERMEDIATE EPIGENETIC SUBGROUP. 2016 6 3309 39 HIGHER GENE EXPRESSION VARIABILITY IN THE MORE AGGRESSIVE SUBTYPE OF CHRONIC LYMPHOCYTIC LEUKEMIA. BACKGROUND: CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) PRESENTS TWO SUBTYPES WHICH HAVE DRASTICALLY DIFFERENT CLINICAL OUTCOMES, IGVH MUTATED (M-CLL) AND IGVH UNMUTATED (U-CLL). SO FAR, THESE TWO SUBTYPES ARE NOT ASSOCIATED TO CLEAR DIFFERENCES IN GENE EXPRESSION PROFILES. INTERESTINGLY, RECENT RESULTS HAVE HIGHLIGHTED IMPORTANT ROLES FOR HETEROGENEITY, BOTH AT THE GENETIC AND AT THE EPIGENETIC LEVEL IN CLL PROGRESSION. METHODS: WE ANALYZED GENE EXPRESSION DATA OF TWO LARGE COHORTS OF CLL PATIENTS AND QUANTIFIED EXPRESSION VARIABILITY ACROSS INDIVIDUALS TO INVESTIGATE DIFFERENCES BETWEEN THE TWO SUBTYPES USING DIFFERENT MEASURES AND STATISTICAL TESTS. FUNCTIONAL SIGNIFICANCE WAS EXPLORED BY PATHWAY ENRICHMENT AND NETWORK ANALYSES. FURTHERMORE, WE IMPLEMENTED A RANDOM FOREST APPROACH BASED ON EXPRESSION VARIABILITY TO CLASSIFY PATIENTS INTO DISEASE SUBTYPES. RESULTS: WE FOUND THAT U-CLL, THE MORE AGGRESSIVE TYPE OF THE DISEASE, SHOWS SIGNIFICANTLY INCREASED VARIABILITY OF GENE EXPRESSION ACROSS PATIENTS AND THAT, OVERALL, GENES THAT SHOW HIGHER VARIABILITY IN THE AGGRESSIVE SUBTYPE ARE RELATED TO CELL CYCLE, DEVELOPMENT AND INTER-CELLULAR COMMUNICATION. THESE FUNCTIONS INDICATE A POTENTIAL RELATION BETWEEN GENE EXPRESSION VARIABILITY AND THE FASTER PROGRESSION OF THIS CLL SUBTYPE. FINALLY, A CLASSIFIER BASED ON GENE EXPRESSION VARIABILITY WAS ABLE TO CORRECTLY PREDICT THE DISEASE SUBTYPE OF CLL PATIENTS. CONCLUSIONS: THERE ARE STRONG RELATIONS BETWEEN GENE EXPRESSION VARIABILITY AND DISEASE SUBTYPE LINKING SIGNIFICANTLY INCREASED EXPRESSION VARIABILITY TO PHENOTYPES SUCH AS AGGRESSIVENESS AND RESISTANCE TO THERAPY IN CLL. 2015 7 3911 29 LIFE-COURSE SOCIOECONOMIC STATUS AND DNA METHYLATION OF GENES REGULATING INFLAMMATION. BACKGROUND: IN HUMANS, LOW SOCIOECONOMIC STATUS (SES) ACROSS THE LIFE COURSE IS ASSOCIATED WITH GREATER DIURNAL CORTISOL PRODUCTION, INCREASED INFLAMMATORY ACTIVITY AND HIGHER CIRCULATING ANTIBODIES FOR SEVERAL PATHOGENS, ALL SUGGESTING A DAMPENED IMMUNE RESPONSE. RECENT EVIDENCE SUGGESTS THAT DNA METHYLATION OF PRO-INFLAMMATORY GENES MAY BE IMPLICATED IN THE BIOLOGICAL EMBEDDING OF THE SOCIAL ENVIRONMENT. METHODS: THE PRESENT STUDY EXAMINES THE ASSOCIATION BETWEEN LIFE-COURSE SES AND DNA METHYLATION OF CANDIDATE GENES, SELECTED ON THE BASIS OF THEIR INVOLVEMENT IN SES-RELATED INFLAMMATION, IN THE CONTEXT OF A GENOME-WIDE METHYLATION STUDY. PARTICIPANTS WERE 857 HEALTHY INDIVIDUALS SAMPLED FROM THE EPIC ITALY PROSPECTIVE COHORT STUDY. RESULTS: INDICATORS OF SES WERE ASSOCIATED WITH DNA METHYLATION OF GENES INVOLVED IN INFLAMMATION. NFATC1, IN PARTICULAR, WAS CONSISTENTLY FOUND TO BE LESS METHYLATED IN INDIVIDUALS WITH LOW VS HIGH SES, IN A DOSE-DEPENDENT MANNER. IL1A, GPR132 AND GENES BELONGING TO THE MAPK FAMILY WERE ALSO LESS METHYLATED AMONG INDIVIDUALS WITH LOW SES. IN ADDITION, ASSOCIATIONS WERE FOUND BETWEEN SES AND CXCL2 AND PTGS2, BUT THESE GENES WERE CONSISTENTLY MORE METHYLATED AMONG LOW SES INDIVIDUALS. CONCLUSIONS: OUR FINDINGS SUPPORT THE HYPOTHESIS THAT THE SOCIAL ENVIRONMENT LEAVES AN EPIGENETIC SIGNATURE IN CELLS. ALTHOUGH THE FUNCTIONAL SIGNIFICANCE OF SES-RELATED DNA METHYLATION IS STILL UNCLEAR, WE HYPOTHESIZE THAT IT MAY LINK SES TO CHRONIC DISEASE RISK. 2015 8 5747 24 SOCIAL ADVERSITY AND EPIGENETIC AGING: A MULTI-COHORT STUDY ON SOCIOECONOMIC DIFFERENCES IN PERIPHERAL BLOOD DNA METHYLATION. LOW SOCIOECONOMIC STATUS (SES) IS ASSOCIATED WITH EARLIER ONSET OF AGE-RELATED CHRONIC CONDITIONS AND REDUCED LIFE-EXPECTANCY, BUT THE UNDERLYING BIOMOLECULAR MECHANISMS REMAIN UNCLEAR. EVIDENCE OF DNA-METHYLATION DIFFERENCES BY SES SUGGESTS A POSSIBLE ASSOCIATION OF SES WITH EPIGENETIC AGE ACCELERATION (AA). WE INVESTIGATED THE ASSOCIATION OF SES WITH AA IN MORE THAN 5,000 INDIVIDUALS BELONGING TO THREE INDEPENDENT PROSPECTIVE COHORTS FROM ITALY, AUSTRALIA, AND IRELAND. LOW SES WAS ASSOCIATED WITH GREATER AA (BETA = 0.99 YEARS; 95% CI 0.39,1.59; P = 0.002; COMPARING EXTREME CATEGORIES). THE RESULTS WERE CONSISTENT ACROSS DIFFERENT SES INDICATORS. THE ASSOCIATIONS WERE ONLY PARTIALLY MODULATED BY THE UNHEALTHY LIFESTYLE HABITS OF INDIVIDUALS WITH LOWER SES. INDIVIDUALS WHO EXPERIENCED LIFE-COURSE SES IMPROVEMENT HAD INTERMEDIATE AA COMPARED TO EXTREME SES CATEGORIES, SUGGESTING REVERSIBILITY OF THE EFFECT AND SUPPORTING THE RELATIVE IMPORTANCE OF THE EARLY CHILDHOOD SOCIAL ENVIRONMENT. SOCIOECONOMIC ADVERSITY IS ASSOCIATED WITH ACCELERATED EPIGENETIC AGING, IMPLICATING BIOMOLECULAR MECHANISMS THAT MAY LINK SES TO AGE-RELATED DISEASES AND LONGEVITY. 2017 9 2423 27 EPIGENETIC SIGNATURES OF SMOKING IN FIVE BRAIN REGIONS. (1) BACKGROUND: EPIGENOME-WIDE ASSOCIATION STUDIES (EWAS) IN PERIPHERAL BLOOD HAVE REPEATEDLY FOUND ASSOCIATIONS BETWEEN TOBACCO SMOKING AND ABERRANT DNA METHYLATION (DNAM), BUT LITTLE IS KNOWN ABOUT DNAM SIGNATURES OF SMOKING IN THE HUMAN BRAIN, WHICH MAY CONTRIBUTE TO THE PATHOPHYSIOLOGY OF ADDICTIVE BEHAVIOR OBSERVED IN CHRONIC SMOKERS. (2) METHODS: WE INVESTIGATED THE SIMILARITY OF DNAM SIGNATURES IN MATCHED BLOOD AND POSTMORTEM BRAIN SAMPLES (N = 10). IN ADDITION, WE PERFORMED EWASS IN FIVE BRAIN REGIONS BELONGING TO THE NEUROCIRCUITRY OF ADDICTION: ANTERIOR CINGULATE CORTEX (ACC), BRODMANN AREA 9, CAUDATE NUCLEUS, PUTAMEN, AND VENTRAL STRIATUM (N = 38-72). (3) RESULTS: CG15925993 WITHIN THE LOC339975 GENE WAS EPIGENOME-WIDE SIGNIFICANT IN THE ACC. OF 16 IDENTIFIED DIFFERENTIALLY METHYLATED REGIONS, TWO (PRSS50 AND LINC00612/A2M-AS1) OVERLAPPED BETWEEN MULTIPLE BRAIN REGIONS. FUNCTIONAL ENRICHMENT WAS DETECTED FOR BIOLOGICAL PROCESSES RELATED TO NEURONAL DEVELOPMENT, INFLAMMATORY SIGNALING AND IMMUNE CELL MIGRATION. ADDITIONALLY, OUR RESULTS INDICATE THE ASSOCIATION OF THE WELL-KNOWN AHRR CPG SITE CG05575921 WITH SMOKING IN THE BRAIN. (4) CONCLUSION: THE PRESENT STUDY PROVIDES FURTHER EVIDENCE OF THE STRONG RELATIONSHIP BETWEEN ABERRANT DNAM AND SMOKING. 2022 10 812 45 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 11 3056 39 GENOME-WIDE DNA METHYLATION ANALYSIS IMPLICATES ENRICHMENT OF INTERFERON PATHWAY IN AFRICAN AMERICAN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS AND EUROPEAN AMERICANS WITH LUPUS NEPHRITIS. SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS A CHRONIC, MULTISYSTEM, INFLAMMATORY AUTOIMMUNE DISEASE THAT DISPROPORTIONATELY AFFECTS WOMEN. TRENDS IN SLE PREVALENCE AND CLINICAL COURSE DIFFER BY ANCESTRY, WITH THOSE OF AFRICAN AMERICAN ANCESTRY PRESENTING WITH MORE ACTIVE, SEVERE AND RAPIDLY PROGRESSIVE DISEASE THAN EUROPEAN AMERICANS. PREVIOUS RESEARCH ESTABLISHED ALTERED EPIGENETIC SIGNATURES IN SLE PATIENTS COMPARED TO CONTROLS. HOWEVER, THE CONTRIBUTION OF ABERRANT DNA METHYLATION (DNAM) TO THE RISK OF SLE BY ANCESTRY AND DIFFERENCES AMONG PATIENTS WITH SLE-ASSOCIATED LUPUS NEPHRITIS (LN) HAS NOT BEEN WELL DESCRIBED. WE EVALUATED THE DNA METHYLOMES OF 87 INDIVIDUALS INCLUDING 41 SLE PATIENTS, WITH AND WITHOUT LN, AND 46 CONTROLS ENROLLED IN AN ANCESTRY DIVERSE, WELL-CHARACTERIZED COHORT STUDY OF ESTABLISHED SLE (41 SLE PATIENTS [20 SLE-LN+, 21 SLE-LN-] AND 46 SEX-, RACE- AND AGE-MATCHED CONTROLS; 55% AFRICAN AMERICAN, 45% EUROPEAN AMERICAN). PARTICIPANTS WERE GENOTYPED USING THE INFINIUM GLOBAL DIVERSITY ARRAY (GDA), AND GENETIC ANCESTRY WAS ESTIMATED USING PRINCIPAL COMPONENTS. GENOME-WIDE DNA METHYLATION WAS INITIALLY MEASURED USING THE ILLUMINA METHYLATIONEPIC 850K BEADCHIP ARRAY FOLLOWED BY METHYLATION-SPECIFIC QPCR TO VALIDATE THE METHYLATION STATUS AT PUTATIVE LOCI. DIFFERENTIALLY METHYLATED POSITIONS (DMP) WERE IDENTIFIED USING A CASE-CONTROL APPROACH ADJUSTED FOR ANCESTRY. WE IDENTIFIED A TOTAL OF 51 DMPS IN CPGS AMONG SLE PATIENTS COMPARED TO CONTROLS. GENES PROXIMAL TO THESE CPGS WERE HIGHLY ENRICHED FOR INVOLVEMENT IN TYPE I INTERFERON SIGNALING. DMPS AMONG EUROPEAN AMERICAN SLE PATIENTS WITH LN WERE SIMILAR TO AFRICAN AMERICAN SLE PATIENTS WITH AND WITHOUT LN. OUR FINDINGS WERE VALIDATED USING AN ORTHOGONAL, METHYL-SPECIFIC PCR FOR THREE SLE-ASSOCIATED DMPS NEAR OR PROXIMAL TO MX1, USP18, AND IFITM1. OUR STUDY CONFIRMS PREVIOUS REPORTS THAT DMPS IN CPGS ASSOCIATED WITH SLE ARE ENRICHED IN TYPE I INTERFERON GENES. HOWEVER, WE SHOW THAT EUROPEAN AMERICAN SLE PATIENTS WITH LN HAVE SIMILAR DNAM PATTERNS TO AFRICAN AMERICAN SLE PATIENTS IRRESPECTIVE OF LN, SUGGESTING THAT ABERRANT DNAM ALTERS ACTIVITY OF TYPE I INTERFERON PATHWAY LEADING TO MORE SEVERE DISEASE INDEPENDENT OF ANCESTRY. 2023 12 1068 30 CLL INTRACLONAL FRACTIONS EXHIBIT ESTABLISHED AND RECENTLY ACQUIRED PATTERNS OF DNA METHYLATION. INTRACLONAL SUBPOPULATIONS OF CIRCULATING CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) CELLS WITH DIFFERENT PROLIFERATIVE HISTORIES AND RECIPROCAL SURFACE EXPRESSION OF CXCR4 AND CD5 HAVE BEEN OBSERVED IN THE PERIPHERAL BLOOD OF CLL PATIENTS AND NAMED PROLIFERATIVE (PF), INTERMEDIATE (IF), AND RESTING (RF) CELLULAR FRACTIONS. HERE, WE FOUND THAT THESE INTRACLONAL CIRCULATING FRACTIONS SHARE PERSISTENT DNA METHYLATION SIGNATURES LARGELY ASSOCIATED WITH THE MUTATION STATUS OF THE IMMUNOGLOBULIN HEAVY CHAIN LOCUS (IGHV) AND THEIR ORIGINS FROM DISTINCT STAGES OF DIFFERENTIATION OF ANTIGEN-EXPERIENCED B CELLS. INCREASED LEUKEMIC BIRTH RATE, HOWEVER, SHOWED A VERY LIMITED IMPACT ON DNA METHYLATION OF CIRCULATING CLL FRACTIONS INDEPENDENT OF IGHV MUTATION STATUS. ADDITIONALLY, DNA METHYLATION HETEROGENEITY INCREASED AS LEUKEMIC CELLS ADVANCED FROM PF TO RF IN THE PERIPHERAL BLOOD. THIS FREQUENTLY CO-OCCURRED WITH HETEROCHROMATIN HYPOMETHYLATION AND HYPERMETHYLATION OF POLYCOMB-REPRESSED REGIONS IN THE PF, SUGGESTING ACCUMULATION OF LONGEVITY-ASSOCIATED EPIGENETIC FEATURES IN RECENTLY BORN CELLS. ON THE OTHER HAND, TRANSCRIPTIONAL DIFFERENCES BETWEEN PAIRED INTRACLONAL FRACTIONS CONFIRMED THEIR PROLIFERATIVE EXPERIENCE AND FURTHER SUPPORTED A LINEAR ADVANCEMENT FROM PF TO RF IN THE PERIPHERAL BLOOD. SEVERAL OF THESE DIFFERENTIALLY EXPRESSED GENES SHOWED UNIQUE ASSOCIATIONS WITH CLINICAL OUTCOME NOT EVIDENT IN THE BULK CLONE, SUPPORTING THE PATHOLOGICAL AND THERAPEUTIC RELEVANCE OF STUDYING INTRACLONAL CLL FRACTIONS. WE CONCLUDE THAT INDEPENDENT METHYLATION AND TRANSCRIPTIONAL LANDSCAPES REFLECT BOTH PREEXISTING CELL-OF-ORIGIN FINGERPRINTS AND MORE RECENTLY ACQUIRED HALLMARKS ASSOCIATED WITH THE LIFE CYCLE OF CIRCULATING CLL CELLS. 2020 13 70 36 A METHOD TO DETECT DIFFERENTIALLY METHYLATED LOCI WITH NEXT-GENERATION SEQUENCING. EPIGENETIC CHANGES, ESPECIALLY DNA METHYLATION AT CPG LOCI HAVE IMPORTANT IMPLICATIONS IN CANCER AND OTHER COMPLEX DISEASES. WITH THE DEVELOPMENT OF NEXT-GENERATION SEQUENCING (NGS), IT IS FEASIBLE TO GENERATE DATA TO INTERROGATE THE DIFFERENCE IN METHYLATION STATUS FOR GENOME-WIDE LOCI USING CASE-CONTROL DESIGN. HOWEVER, A PROPER AND EFFICIENT STATISTICAL TEST IS LACKING. THERE ARE SEVERAL CHALLENGES. FIRST, UNLIKE METHYLATION EXPERIMENTS USING MICROARRAYS, WHERE THERE IS ONE MEASURE OF METHYLATION FOR ONE INDIVIDUAL AT A PARTICULAR CPG SITE, HERE WE HAVE THE COUNTS OF METHYLATION ALLELE AND UNMETHYLATION ALLELE FOR EACH INDIVIDUAL. SECOND, DUE TO THE NATURE OF SAMPLE PREPARATION, THE MEASURED METHYLATION REFLECTS THE METHYLATION STATUS OF A MIXTURE OF CELLS INVOLVED IN SAMPLE PREPARATION. THEREFORE, THE UNDERLYING DISTRIBUTION OF THE MEASURED METHYLATION LEVEL IS UNKNOWN, AND A ROBUST TEST IS MORE DESIRABLE THAN PARAMETRIC APPROACH. THIRD, CURRENTLY NGS MEASURES METHYLATION AT OVER 2 MILLION CPG SITES. ANY STATISTICAL TESTS HAVE TO BE COMPUTATIONALLY EFFICIENT IN ORDER TO BE APPLIED TO THE NGS DATA. TAKING THESE CHALLENGES INTO ACCOUNT, WE PROPOSE A TEST FOR DIFFERENTIAL METHYLATION BASED ON CLUSTERED DATA ANALYSIS BY MODELING THE METHYLATION COUNTS. WE PERFORMED SIMULATIONS TO SHOW THAT IT IS ROBUST UNDER SEVERAL DISTRIBUTIONS FOR THE MEASURED METHYLATION LEVELS. IT HAS GOOD POWER AND IS COMPUTATIONALLY EFFICIENT. FINALLY, WE APPLY THE TEST TO OUR NGS DATA ON CHRONIC LYMPHOCYTIC LEUKEMIA. THE RESULTS INDICATE THAT IT IS A PROMISING AND PRACTICAL TEST. 2013 14 2639 32 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 15 5882 31 SYSTEMATIC REVIEW OF LUNG FUNCTION AND COPD WITH PERIPHERAL BLOOD DNA METHYLATION IN POPULATION BASED STUDIES. BACKGROUND: EPIGENETIC VARIATIONS IN PERIPHERAL BLOOD HAVE POTENTIAL AS BIOMARKERS FOR DISEASE. THIS SYSTEMATIC REVIEW ASSESSES THE ASSOCIATION OF LUNG FUNCTION AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) WITH DNA METHYLATION PROFILES IN PERIPHERAL BLOOD FROM POPULATION-BASED STUDIES. METHODS: ONLINE DATABASES MEDLINE, EMBASE, AND WEB OF SCIENCE WERE SEARCHED. GOOGLE SCHOLAR WAS SEARCHED TO IDENTIFY GREY LITERATURE. AFTER REMOVING DUPLICATE ARTICLES, 1155 ARTICLES WERE INDEPENDENTLY SCREENED BY TWO INVESTIGATORS. PEER REVIEWED REPORTS ON POPULATION-BASED STUDIES THAT EXAMINED PERIPHERAL BLOOD DNA METHYLATION IN PARTICIPANTS WITH MEASURED LUNG FUNCTION (FEV1, FEV1/FVC RATIO) OR KNOWN COPD STATUS WERE SELECTED FOR FULL-TEXT REVIEW. SIX ARTICLES WERE SUITABLE FOR INCLUSION. INFORMATION REGARDING STUDY CHARACTERISTICS, DESIGNS, METHODOLOGIES AND CONCLUSIONS WAS EXTRACTED. A NARRATIVE SYNTHESIS WAS PERFORMED BASED ON PUBLISHED RESULTS. RESULTS: THREE OF THE SIX ARTICLES ASSESSED THE ASSOCIATION OF COPD WITH DNA METHYLATION, AND TWO OF THESE ALSO INCLUDED ASSOCIATIONS WITH LUNG FUNCTION. OVERALL, FIVE REPORTS EXAMINED THE ASSOCIATION OF LUNG FUNCTION WITH DNA METHYLATION PROFILES. FIVE OF THE SIX ARTICLES REPORTED 'SIGNIFICANT' RESULTS. HOWEVER, NO CONSISTENT CPG SITES WERE IDENTIFIED ACROSS STUDIES FOR COPD STATUS OR LUNG FUNCTION VALUES. CONCLUSIONS: DNA METHYLATION PATTERNS IN PERIPHERAL BLOOD FROM INDIVIDUALS WITH REDUCED LUNG FUNCTION OR COPD MAY BE DIFFERENT TO THOSE IN PEOPLE WITH NORMAL LUNG FUNCTION. HOWEVER, THIS SYSTEMATIC REVIEW DID NOT FIND ANY CONSISTENT ASSOCIATIONS OF LUNG FUNCTION OR COPD WITH DIFFERENTIALLY METHYLATED CPG SITES. LARGE STUDIES WITH A LONGITUDINAL DESIGN TO ADDRESS REVERSE CAUSALITY MAY PROVE A MORE FRUITFUL AREA OF RESEARCH. TRIAL REGISTRATION: PROSPERO 2016: CRD42016037352 . 2017 16 1581 27 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 1194 35 CORRELATION OF EPIGENETIC CHANGE AND IDENTIFICATION OF RISK FACTORS FOR ORAL SUBMUCOUS FIBROSIS. BACKGROUND: DNA METHYLATION OF CERTAIN GENES IS AN EPIGENETIC CHANGE THAT IS ESSENTIAL FOR TUMORIGENESIS. ORAL SUBMUCOUS FIBROSIS (OSF) IS A PRECANCEROUS CONDITION OF ORAL MUCOSA WITH INFLAMMATION AND PROGRESSIVE FIBROSIS OF THE LAMINA PROPRIA AND DEEPER CONNECTIVE TISSUE. THE HYPERMETHYLATION OF E-CADHERIN AND CYCLOOXYGENASE 2 (COX-2) IN CHRONIC INFLAMMATION MAY DEMONSTRATE A MILD LESION/MUTATION AT EPIGENETIC LEVELS. THIS STUDY COMPARES THE HYPERMETHYLATION STATUS OF E-CADHERIN AND COX-2 GENES IN PATIENTS WITH ORAL CANCER AND PATIENTS WITH OSF AND ALSO AIMS TO IDENTIFY RISK FACTORS FOR THE DEVELOPMENT OF OSF. METHODS: DNA WAS EXTRACTED FROM BLOOD SAMPLES OF 50 HEALTHY SUBJECTS, 50 PATIENTS WITH OSF AND 60 PATIENTS WITH ORAL CANCER. METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION FOR E-CADHERIN AND COX-2 WAS PERFORMED ON THESE SAMPLES AND THE PRODUCTS WERE ANALYZED ON 2% AGAROSE GEL. SURVEYS ABOUT ORAL HEALTH HABITS AND CLINICAL PERIODONTAL EXAMINATIONS IN PATIENTS WITH OSF AND HEALTHY SUBJECTS WERE ALSO CONDUCTED BY WELL-TRAINED DENTISTS, AND LOGISTIC REGRESSION WAS PERFORMED TO IDENTIFY RISK FACTORS FOR OSF. RESULTS: HYPERMETHYLATION OF E-CADHERIN AND COX-2 WAS OBSERVED IN 36% AND 22% OF ORAL CANCER SAMPLES, RESPECTIVELY. IN PATIENTS WITH OSF, THE RATES WERE 52% AND 30%, AND IN HEALTHY CONTROLS THE RATES WERE 4% AND 6%. HYPERMETHYLATION WAS SHOWN TO BE CORRELATED BETWEEN THE 3 GROUPS WITH STATISTICAL SIGNIFICANCE (P<0.01). METHYLATION OF CPG ISLANDS IN E-CADHERIN AND COX-2 OCCURRED MORE FREQUENTLY IN PATIENTS WITH OSF THAN IN THE CONTROL GROUP, BUT LESS FREQUENTLY THAN IN PATIENTS WITH ORAL CANCER. IN THE LOGISTIC REGRESSION ANALYSIS, SMOKING, BRUSHING MORE THAN TWICE DAILY, PERIODONTAL PROBING DEPTH AND PLAQUE INDEX WERE IDENTIFIED AS 4 MAJOR RISK FACTORS FOR OSF. CONCLUSIONS: THESE DATA CONFIRM THAT E-CADHERIN AND COX-2 EXPRESSIONS ARE RELATED TO OSF. THE EPIGENETIC CHANGES PRESENTED IN PATIENTS WITH CHRONIC INFLAMMATION MIGHT DEMONSTRATE AN IRREVERSIBLE DESTRUCTION IN THE TISSUES OR ORGANS SIMILAR TO THE EFFECTS OF CANCER. CHRONIC OSF WAS SIGNIFICANTLY ASSOCIATED WITH HYPERMETHYLATION, A CANCER RISK FACTOR. 2012 18 391 33 AN INTRODUCTION TO THE MATHEMATICAL MODELING IN THE STUDY OF CANCER SYSTEMS BIOLOGY. BACKGROUND: FREQUENTLY OCCURRING IN CANCER ARE THE ABERRANT ALTERATIONS OF REGULATORY ONCO-METABOLITES, VARIOUS ONCOGENES/EPIGENETIC STOCHASTICITY, AND SUPPRESSOR GENES, AS WELL AS THE DEFICIENT MISMATCH REPAIR MECHANISM, CHRONIC INFLAMMATION, OR THOSE DEVIATIONS BELONGING TO THE OTHER CANCER CHARACTERISTICS. HOW THESE ABERRATIONS THAT EVOLVE OVERTIME DETERMINE THE GLOBAL PHENOTYPE OF MALIGNANT TUMORS REMAINS TO BE COMPLETELY UNDERSTOOD. DYNAMIC ANALYSIS MAY HAVE POTENTIAL TO REVEAL THE MECHANISM OF CARCINOGENESIS AND CAN OFFER NEW THERAPEUTIC INTERVENTION. AIMS: WE INTRODUCE SIMPLIFIED MATHEMATICAL TOOLS TO MODEL SERIAL QUANTITATIVE DATA OF CANCER BIOMARKERS. WE ALSO HIGHLIGHT AN INTRODUCTORY OVERVIEW OF MATHEMATICAL TOOLS AND MODELS AS THEY APPLY FROM THE VIEWPOINT OF KNOWN CANCER FEATURES. METHODS: MATHEMATICAL MODELING OF POTENTIALLY ACTIONABLE GENOMIC PRODUCTS AND HOW THEY PROCEED OVERTIME DURING TUMORIGENESIS ARE EXPLORED. THIS REPORT IS INTENDED TO BE INSTINCTIVE WITHOUT BEING OVERLY TECHNICAL. RESULTS: TO DATE, MANY MATHEMATICAL MODELS OF THE COMMON FEATURES OF CANCER HAVE BEEN DEVELOPED. HOWEVER, THE DYNAMIC OF INTEGRATED HETEROGENEOUS PROCESSES AND THEIR CROSS TALKS RELATED TO CARCINOGENESIS REMAINS TO BE RESOLVED. CONCLUSIONS: IN CANCER RESEARCH, OUTLINING MATHEMATICAL MODELING OF EXPERIMENTALLY OBTAINED DATA SNAPSHOTS OF MOLECULAR SPECIES MAY PROVIDE INSIGHTS INTO A BETTER UNDERSTANDING OF THE MULTIPLE BIOCHEMICAL CIRCUITS. RECENT DISCOVERIES HAVE PROVIDED SUPPORT FOR THE EXISTENCE OF COMPLEX CANCER PROGRESSION IN DYNAMICS THAT SPAN FROM A SIMPLE 1-DIMENSIONAL DETERMINISTIC SYSTEM TO A STOCHASTIC (IE, PROBABILISTIC) OR TO AN OSCILLATORY AND MULTISTABLE NETWORKS. FURTHER RESEARCH IN MATHEMATICAL MODELING OF CANCER PROGRESSION, BASED ON THE EVOLVING MOLECULAR KINETICS (TIME SERIES), COULD INFORM A SPECIFIC AND A PREDICTIVE BEHAVIOR ABOUT THE GLOBAL SYSTEMS BIOLOGY OF VULNERABLE TUMOR CELLS IN THEIR EARLIER STAGES OF ONCOGENESIS. ON THIS FOOTING, NEW PREVENTIVE MEASURES AND ANTICANCER THERAPY COULD THEN BE CONSTRUCTED. 2018 19 22 24 5-HYDROXYMETHYLCYTOSINE AS A CLINICAL BIOMARKER: FLUORESCENCE-BASED ASSAY FOR HIGH-THROUGHPUT EPIGENETIC QUANTIFICATION IN HUMAN TISSUES. EPIGENETIC TRANSFORMATIONS MAY PROVIDE EARLY INDICATORS FOR CANCER AND OTHER DISEASE. SPECIFICALLY, THE AMOUNT OF GENOMIC 5-HYDROXYMETHYLCYTOSINE (5-HMC) WAS SHOWN TO BE GLOBALLY REDUCED IN A WIDE RANGE OF CANCERS. THE INTEGRATION OF THIS GLOBAL BIOMARKER INTO DIAGNOSTIC WORKFLOWS IS HAMPERED BY THE LIMITATIONS OF CURRENT 5-HMC QUANTIFICATION METHODS. HERE WE PRESENT AND VALIDATE A FLUORESCENCE-BASED PLATFORM FOR HIGH-THROUGHPUT AND COST-EFFECTIVE QUANTIFICATION OF GLOBAL GENOMIC 5-HMC LEVELS. WE UTILIZED THE ASSAY TO CHARACTERIZE CANCEROUS TISSUES BASED ON THEIR 5-HMC CONTENT, AND OBSERVED A PRONOUNCED REDUCTION IN 5-HMC LEVEL IN VARIOUS CANCER TYPES. WE PRESENT DATA FOR GLIOBLASTOMA, COLORECTAL CANCER, MULTIPLE MYELOMA, CHRONIC LYMPHOCYTIC LEUKEMIA AND PANCREATIC CANCER, COMPARED TO CORRESPONDING CONTROLS. POTENTIALLY, THE TECHNIQUE COULD ALSO BE USED TO FOLLOW RESPONSE TO TREATMENT FOR PERSONALIZED TREATMENT SELECTION. WE PRESENT INITIAL PROOF-OF-CONCEPT DATA FOR TREATMENT OF FAMILIAL ADENOMATOUS POLYPOSIS. 2020 20 1064 42 CLINICAL SIGNIFICANCE OF PROMOTER METHYLATION STATUS OF TUMOR SUPPRESSOR GENES IN CIRCULATING DNA OF PANCREATIC CANCER PATIENTS. INTRODUCTION: PANCREATIC DUCTAL ADENOCARCINOMA (PDAC) IS A VERY AGGRESSIVE CANCER. THERE ARE VARIOUS SUB-CELLULAR EVENTS (BOTH GENETIC AND EPIGENETIC) THAT GET DYSREGULATED LEADING TO TUMORIGENESIS. METHYLATION IN PROMOTERS OF TUMOR SUPPRESSOR GENES IS ONE OF THESE EPIGENETIC PHENOMENA CONTRIBUTING TO THE PATHOGENESIS OF CANCER. GENES ANALYZED FOR PROMOTER METHYLATION STATUS IN THIS STUDY NAMELY SPARC (SECRETED PROTEIN ACIDIC AND RICH IN CYSTEINE, UCHL1 (UBIQUITIN CARBOXY-TERMINAL HYDROLASE L1), NPTX2 (NEURONAL PENTRAXIN 2), PENK (PROENKEPHALIN) HAD BEEN STUDIED IN PANCREATIC CANCER, BUT THERE IS A NEED TO CHECK METHYLATION IN THESE GENES AS CIRCULATORY NON-INVASIVE MARKERS. THIS STUDY ANALYZED THE ABSOLUTE QUANTIFICATION OF METHYLATION LEVELS OF SPARC, UCHL1, PENK, AND NPTX2 GENES PROMOTERS IN PDAC PATIENTS AS WELL AS IN CHRONIC PANCREATITIS (CP) PATIENTS AND HEALTHY SUBJECTS (HC) AND EVALUATED ITS CLINICAL SIGNIFICANCE IN PDAC. MATERIALS AND METHODS: THE STUDY INCLUDED 65 PDAC PATIENTS, 25 CP PATIENTS, AND 25 HEALTHY CONTROLS. DNA WAS EXTRACTED FROM THEIR PLASMA SAMPLES AND SUBSEQUENTLY GIVEN BISULFITE TREATMENT. ABSOLUTE QUANTIZATION OF METHYLATED AND UNMETHYLATED COPIES OF GENE PROMOTERS OF ALL THE FOUR GENES WAS PERFORMED USING REAL-TIME PCR (SYBR GREEN) BY THE STANDARD CURVE METHOD. METHYLATION LEVELS WERE EXPRESSED AS METHYLATION INDEX (MI) FOR EACH GENE IN EACH PATIENT. MI WAS CALCULATED FROM ABSOLUTE COPY NUMBERS AS FOLLOWS: MI-METHYLATED COPY NUMBER/METHYLATED COPY NUMBER + UNMETHYLATED COPY NUMBER). THESE INDICES WERE USED TO COMPARE GENE METHYLATION LEVELS WITHIN DIFFERENT GROUPS AND TO CORRELATE WITH CLINICOPATHOLOGICAL FEATURES AND SURVIVAL OF PANCREATIC CANCER PATIENTS. AN APPROPRIATE STATISTICAL ANALYSIS WAS APPLIED. RESULTS: METHYLATION INDICES FOR ALL THE FOUR GENES IN PDAC CASES WERE FOUND TO BE SIGNIFICANTLY HIGHER AS COMPARED TO THAT IN HEALTHY INDIVIDUALS. SPARC MI VALUES WERE FOUND TO DIFFERENTIATE EARLY-STAGE PDAC PATIENTS FROM CP PATIENTS. PDAC PATIENTS WITH THE METASTASIZED DISEASE AND STAGE IV DISEASE WERE FOUND TO HAVE HIGH MI FOR THE SPARC GENE AS WELL AS FOR THE NPTX2 GENE, WHILE A HIGHER UCHL1 METHYLATION INDEX WAS FOUND TO CORRELATE WITH AN ADVANCED STAGE OF THE DISEASE. HIGHER MI VALUES FOR SPARC AND NPTX2 GENES WERE FOUND TO ASSOCIATE WITH POOR SURVIVAL IN PATIENTS WITH PDAC. CONCLUSION: METHYLATION LOAD IN THE FORM OF MI FOR EACH OF THE FOUR GENES ASSESSED IN PLASMA MAY EMERGE AS A NON-INVASIVE BIOMARKER TO DIFFERENTIATE PANCREATIC CANCER FROM HEALTHY INDIVIDUALS. BUT ONLY SPARC AND NPTX2 HYPERMETHYLATION WERE ABLE TO DISTINGUISH PANCREATIC CANCER FROM CHRONIC PANCREATITIS. ASSOCIATION OF ABERRANT METHYLATION IN SPARC AND NPTX2 GENE WITH METASTASIS AND POOR SURVIVAL OF PATIENTS SUGGEST THE ROLE OF METHYLATION IN THESE GENES AS PROGNOSTIC MARKERS. 2020