1 1602 140 DNA METHYLATION SIGNATURES OF PULMONARY ARTERIAL SMOOTH MUSCLE CELLS IN CHRONIC THROMBOEMBOLIC PULMONARY HYPERTENSION. CHRONIC THROMBOEMBOLIC PULMONARY HYPERTENSION (CTEPH) IS A LIFE-THREATENING DISEASE, WHICH IS OFTEN UNDERPINNED BY VASCULAR REMODELING. PULMONARY ARTERIAL SMOOTH MUSCLE CELLS (PASMCS) ARE THE MAIN PARTICIPANTS IN VASCULAR REMODELING. HOWEVER, THEIR BIOLOGICAL ROLE IN CTEPH IS NOT ENTIRELY CLEAR. IN THE PRESENT STUDY, WE ANALYZED THE WHOLE EPIGENOME-WIDE DNA METHYLATION PROFILE OF CULTURED PASMCS FROM CTEPH AND CONTROL CELL LINES WITH THE ILLUMINA HUMAN METHYLATION 450K BEADCHIP. A TOTAL OF 6,829 SIGNIFICANTLY DIFFERENTIALLY METHYLATED PROBES (DMPS) WERE DETECTED BETWEEN THESE TWO GROUPS. AMONG THESE, 4,246 DMPS WERE HYPERMETHYLATED, WHILE 2,583 DMPS WERE HYPOMETHYLATED. THE FUNCTIONAL ENRICHMENT ANALYSIS OF 1,743 DMPS IN THE PROMOTER REGIONS AND CORRESPONDING GENES INDICATED THAT DNA HYPERMETHYLATION AND HYPOMETHYLATION MIGHT BE INVOLVED IN THE REGULATION OF GENES THAT HAVE MULTIFARIOUS BIOLOGICAL ROLES, INCLUDING ROLES IN CANCER-RELATED DISEASES, THE REGULATION OF THE ACTIN CYTOSKELETON, CELL ADHESION, AND PATTERN SPECIFICATION PROCESSES. THE OBSERVED METHYLATIONS WERE CATEGORIZED INTO THE MOST IMPORTANT FUNCTIONS, INCLUDING THOSE INVOLVED IN CELL PROLIFERATION, IMMUNITY, AND MIGRATION. WE SPECULATE THAT THESE METHYLATIONS WERE MOST LIKELY INVOLVED IN THE POSSIBLE PATHOPHYSIOLOGY OF CTEPH. GENE INTERACTION ANALYSIS PERTAINING TO SIGNAL NETWORKS CONFIRMED THAT PIK3CA AND PIK3R1 WERE IMPORTANT MEDIATORS IN THESE WHOLE NETWORKS. THE MRNA LEVELS OF PIK3CA, HIC1, AND SSH1 WERE VERIFIED BY QPCR AND CORRESPONDED WITH DNA METHYLATION DIFFERENCES. UNDERSTANDING EPIGENETIC FEATURES ASSOCIATED WITH CTEPH MAY PROVIDE NEW INSIGHTS INTO THE MECHANISM THAT UNDERLIE THIS CONDITION. 2018 2 3069 43 GENOME-WIDE DNA METHYLATION PROFILING IDENTIFIES EPIGENETIC CHANGES IN CD4+ AND CD14+ CELLS OF MULTIPLE SCLEROSIS PATIENTS. MULTIPLE SCLEROSIS (MS) IS A CHRONIC AUTOIMMUNE AND DEGENERATIVE DISEASE OF THE CENTRAL NERVOUS SYSTEM, WHICH DEVELOPS IN GENETICALLY PREDISPOSED INDIVIDUALS UPON EXPOSURE TO ENVIRONMENTAL INFLUENCES. ENVIRONMENTAL TRIGGERS OF MS, SUCH AS VIRAL INFECTIONS OR SMOKING, WERE DEMONSTRATED TO AFFECT DNA METHYLATION, AND THUS TO INVOLVE THIS IMPORTANT EPIGENETIC MECHANISM IN THE DEVELOPMENT OF PATHOLOGICAL PROCESS. TO IDENTIFY MS-ASSOCIATED DNA METHYLATION HALLMARKS, WE PERFORMED GENOME-WIDE DNA METHYLATION PROFILING OF TWO CELL POPULATIONS (CD4+ T-LYMPHOCYTES AND CD14+ MONOCYTES), COLLECTED FROM THE SAME TREATMENT-NAIVE RELAPSING-REMITTING MS PATIENTS AND HEALTHY SUBJECTS, USING ILLUMINA 450 K METHYLATION ARRAYS. WE REVEALED SIGNIFICANT CHANGES IN DNA METHYLATION FOR BOTH CELL POPULATIONS IN MS. IN CD4+ CELLS OF MS PATIENTS THE MAJORITY OF DIFFERENTIALLY METHYLATED POSITIONS (DMPS) WERE SHOWN TO BE HYPOMETHYLATED, WHILE IN CD14+ CELLS - HYPERMETHYLATED. DIFFERENTIAL METHYLATION OF HLA-DRB1 GENE IN CD4+ AND CD14+ CELLS WAS ASSOCIATED WITH CARRIAGE OF DRB1*15 ALLELE INDEPENDENTLY FROM THE DISEASE STATUS. BESIDES, ABOUT 20% OF IDENTIFIED DMPS WERE SHARED BETWEEN TWO CELL POPULATIONS AND HAD THE SAME DIRECTION OF METHYLATION CHANGES; THEY MAY BE INVOLVED IN BASIC EPIGENETIC PROCESSES OCCURING IN MS. THESE FINDINGS SUGGEST THAT THE EPIGENETIC MECHANISM OF DNA METHYLATION IN IMMUNE CELLS CONTRIBUTES TO MS; FURTHER STUDIES ARE NOW REQUIRED TO VALIDATE THESE RESULTS AND UNDERSTAND THEIR FUNCTIONAL SIGNIFICANCE. 2022 3 1587 30 DNA METHYLATION PROFILING IDENTIFIES NOVEL MARKERS OF PROGRESSION IN HEPATITIS B-RELATED CHRONIC LIVER DISEASE. BACKGROUND: CHRONIC HEPATITIS B INFECTION IS CHARACTERIZED BY HEPATIC IMMUNE AND INFLAMMATORY RESPONSE WITH CONSIDERABLE VARIATION IN THE RATES OF PROGRESSION TO CIRRHOSIS. GENETIC VARIANTS AND ENVIRONMENTAL CUES INFLUENCE PREDISPOSITION TO THE DEVELOPMENT OF CHRONIC LIVER DISEASE; HOWEVER, IT REMAINS UNKNOWN IF ABERRANT DNA METHYLATION IS ASSOCIATED WITH FIBROSIS PROGRESSION IN CHRONIC HEPATITIS B. RESULTS: TO IDENTIFY EPIGENETIC MARKS ASSOCIATED WITH INFLAMMATORY AND FIBROTIC PROCESSES OF THE HEPATITIS B-INDUCED CHRONIC LIVER DISEASE, WE CARRIED OUT HEPATIC GENOME-WIDE METHYLATION PROFILING USING ILLUMINA INFINIUM BEADARRAYS COMPARING MILD AND SEVERE FIBROTIC DISEASE IN A DISCOVERY COHORT OF 29 PATIENTS. WE OBTAINED 310 DIFFERENTIALLY METHYLATED REGIONS AND SELECTED FOUR LOCI COMPRISING THREE GENES FROM THE TOP DIFFERENTIALLY METHYLATED REGIONS: HYPERMETHYLATION OF HOXA2 AND HDAC4 ALONG WITH HYPOMETHYLATION OF PPP1R18 WERE SIGNIFICANTLY LINKED TO SEVERE FIBROSIS. WE REPLICATED THE PROMINENT METHYLATION MARKS IN AN INDEPENDENT COHORT OF 102 PATIENTS BY BISULFITE MODIFICATION AND PYROSEQUENCING. THE TIMING AND CAUSAL RELATIONSHIP OF EPIGENETIC MODIFICATIONS WITH DISEASE SEVERITY WAS FURTHER INVESTIGATED USING A COHORT OF PATIENTS WITH SERIAL BIOPSIES. CONCLUSIONS: OUR FINDINGS SUGGEST A LINKAGE OF WIDESPREAD EPIGENETIC DYSREGULATION WITH DISEASE PROGRESSION IN CHRONIC HEPATITIS B INFECTION. CPG METHYLATION AT NOVEL GENES SHEDS LIGHT ON NEW MOLECULAR PATHWAYS, WHICH CAN BE POTENTIALLY EXPLOITED AS A BIOMARKER OR TARGETED TO ATTENUATE INFLAMMATION AND FIBROSIS. 2016 4 1909 45 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