1 1579 161 DNA METHYLATION PROFILE OF LIVER OF MICE CONCEIVED BY IN VITRO FERTILIZATION. OFFSPRING GENERATED BY IN VITRO FERTILIZATION (IVF) ARE BELIEVED TO BE HEALTHY BUT DISPLAY A POSSIBLE PREDISPOSITION TO CHRONIC DISEASES, LIKE HYPERTENSION AND GLUCOSE INTOLERANCE. SINCE EPIGENETIC CHANGES ARE BELIEVED TO UNDERLIE SUCH PHENOTYPE, THIS STUDY AIMED AT DESCRIBING GLOBAL DNA METHYLATION CHANGES IN THE LIVER OF ADULT MICE GENERATED BY NATURAL MATING (FB GROUP) OR BY IVF. EMBRYOS WERE GENERATED BY IVF OR NATURAL MATING. AT 30 WEEKS OF AGE, MICE WERE SACRIFICED. THE LIVER WAS REMOVED, AND GLOBAL DNA METHYLATION WAS ASSESSED USING WHOLE-GENOME BISULFITE SEQUENCING (WGBS). GENOMIC REGIONS FOR ENRICHMENT ANALYSIS TOOL (GREAT) AND G:PROFILERBETA WERE USED TO IDENTIFY DIFFERENTIALLY METHYLATED REGIONS (DMRS) AND FOR FUNCTIONAL ENRICHMENT ANALYSIS. OVERREPRESENTED GENE ONTOLOGY TERMS WERE SUMMARIZED WITH REVIGO, WHILE CANONICAL PATHWAYS (CPS) WERE IDENTIFIED WITH INGENUITY(R) PATHWAY ANALYSIS. OVERALL, 2692 DMRS (4.91%) WERE DIFFERENT BETWEEN THE GROUPS. THE MAJORITY OF DMRS (84.92%) WERE HYPOMETHYLATED IN THE IVF GROUP. SURPRISINGLY, ONLY 0.16% OF CPG ISLANDS WERE DIFFERENTIALLY METHYLATED AND ONLY A FEW DMRS WERE LOCATED ON KNOWN GENE PROMOTERS (N = 283) OR ENHANCERS (N = 190). NOTABLY, THE LONG-INTERSPERSED ELEMENT (LINE), SHORT-INTERSPERSED ELEMENT (SINE), AND LONG TERMINAL REPEAT (LTR1) TRANSPOSABLE ELEMENTS SHOWED REDUCED METHYLATION (P < 0.05) IN IVF LIVERS. CELLULAR METABOLIC PROCESS, HEPATIC FIBROSIS, AND INSULIN RECEPTOR SIGNALING WERE SOME OF THE PRINCIPAL BIOLOGICAL PROCESSES AND CPS MODIFIED BY IVF. IN SUMMARY, IVF MODIFIES THE DNA METHYLATION SIGNATURE IN THE ADULT LIVER, RESULTING IN HYPOMETHYLATION OF GENES INVOLVED IN METABOLISM AND GENE TRANSCRIPTION REGULATION. THESE FINDINGS MAY SHED LIGHT ON THE MECHANISMS UNDERLYING THE DEVELOPMENTAL ORIGIN OF HEALTH AND DISEASE. 2022 2 1607 34 DNA METHYLATION, COLON CANCER AND MEDITERRANEAN DIET: RESULTS FROM THE EPIC-ITALY COHORT. THE BIOLOGICAL MECHANISMS THROUGH WHICH ADHERENCE TO MEDITERRANEAN DIET (MD) PROTECTS AGAINST COLON CANCER (CC) ARE POORLY UNDERSTOOD. EVIDENCE SUGGESTS THAT CHRONIC INFLAMMATION MAY BE IMPLICATED IN THE PATHWAY. BOTH DIET AND CC ARE RELATED TO EPIGENETIC REGULATION. WE PERFORMED A NESTED CASE-CONTROL STUDY ON 161 PAIRS FROM THE ITALIAN COMPONENT OF THE EUROPEAN PROSPECTIVE INVESTIGATION INTO CANCER AND NUTRITION (EPIC) COHORT, IN WHICH WE LOOKED FOR THE METHYLATION SIGNALS IN DNA EXTRACTED FROM LEUCOCYTES ASSOCIATED WITH BOTH CC AND MD IN 995 CPGS LOCATED IN 48 INFLAMMATION GENES. THE DNA METHYLATION SIGNALS DETECTED IN THIS ANALYSIS WERE VALIDATED IN A SUBGROUP OF 47 CASE-CONTROL PAIRS AND FURTHER REPLICATED (WHERE VALIDATED) IN 95 NEW PAIRS BY MEANS OF PYROSEQUENCING. AMONG THE CPG SITES SELECTED A-PRIORI IN INFLAMMATION-RELATED GENES, SEVEN CPG SITES WERE FOUND TO BE ASSOCIATED WITH CC STATUS AND WITH MD, IN LINE WITH ITS PROTECTIVE EFFECT. ONLY TWO CPG SITES (CG17968347-SERPINE1 AND CG20674490-RUNX3) WERE VALIDATED USING BISULPHITE PYROSEQUENCING AND, AFTER REPLICATION, WE FOUND THAT DNA METHYLATION OF CG20674490-RUNX3 MAY BE A POTENTIAL MOLECULAR MEDIATOR EXPLAINING THE PROTECTIVE EFFECT OF MD ON CC ONSET. THE USE OF A 'MEET-IN-THE-MIDDLE' APPROACH TO IDENTIFY THE OVERLAP BETWEEN EXPOSURE AND PREDICTIVE MARKERS OF DISEASE IS INNOVATIVE IN STUDIES ON THE RELATIONSHIP BETWEEN DIET AND CANCER, IN WHICH EXPOSURE ASSESSMENT IS DIFFICULT AND THE MECHANISMS THROUGH WHICH THE NUTRIENTS EXERT THEIR PROTECTIVE EFFECT IS LARGELY UNKNOWN. 2019 3 1545 40 DNA METHYLATION IN LIVER TUMORIGENESIS IN FISH FROM THE ENVIRONMENT. THE LINK BETWEEN ENVIRONMENT, ALTERATION IN DNA METHYLATION AND CANCER HAS BEEN WELL ESTABLISHED IN HUMANS; YET, IT IS UNDER-STUDIED IN UNSEQUENCED NON-MODEL ORGANISMS. THE OCCURRENCE OF LIVER TUMORS IN THE FLATFISH DAB COLLECTED AT CERTAIN UK SAMPLING SITES EXCEEDS 20%, YET THE CAUSATIVE AGENTS AND THE MOLECULAR MECHANISMS OF TUMOR FORMATION ARE NOT KNOWN, ESPECIALLY REGARDING THE BALANCE BETWEEN EPIGENETIC AND GENETIC FACTORS. METHYLATED DNA IMMUNOPRECIPITATION (MEDIP) COMBINED WITH DE NOVO HIGH-THROUGHPUT DNA SEQUENCING WERE USED TO INVESTIGATE DNA METHYLATION CHANGES IN DAB HEPATOCELLULAR ADENOMA TUMORS FOR THE FIRST TIME IN AN UNSEQUENCED SPECIES. NOVEL CUSTOM-MADE DAB GENE EXPRESSION ARRAYS WERE DESIGNED AND USED TO DETERMINE THE RELATIONSHIP BETWEEN DNA METHYLATION AND GENE EXPRESSION. IN ADDITION, THE CONFIRMATORY TECHNIQUES OF BISULFITE SEQUENCING PCR (BSP) AND RT-PCR WERE APPLIED. GENES INVOLVED IN PATHWAYS RELATED TO CANCER, INCLUDING APOPTOSIS, WNT/BETA-CATENIN SIGNALING AND GENOMIC AND NON-GENOMIC ESTROGEN RESPONSES, WERE ALTERED BOTH IN METHYLATION AND TRANSCRIPTION. GLOBAL METHYLATION WAS STATISTICALLY SIGNIFICANTLY 1.8-FOLD REDUCED IN HEPATOCELLULAR ADENOMA AND NON-CANCEROUS SURROUNDING TISSUES COMPARED WITH LIVER FROM NON-CANCER BEARING DAB. BASED ON THE IDENTIFIED CHANGES AND CHEMICAL EXPOSURE DATA, OUR STUDY SUPPORTS THE EPIGENETIC MODEL OF CANCER. WE HYPOTHESIZE THAT CHRONIC EXPOSURE TO A MIXTURE OF ENVIRONMENTAL CONTAMINANTS CONTRIBUTES TO A GLOBAL HYPOMETHYLATION FOLLOWED BY FURTHER EPIGENETIC AND GENOMIC CHANGES. THE FINDINGS SUGGEST A LINK BETWEEN ENVIRONMENT, EPIGENETICS AND CANCER IN FISH TUMORS IN THE WILD AND SHOW THE UTILITY OF THIS METHODOLOGY FOR STUDIES IN NON-MODEL ORGANISMS. 2011 4 1909 50 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