1 1190 107 CORRELATION BETWEEN HEPATIC HUMAN MALES ABSENT ON THE FIRST (HMOF) AND VIRAL PERSISTENCE IN CHRONIC HEPATITIS B PATIENTS. BACKGROUND: CHRONIC HEPATITIS B (CHB) REMAINS A GLOBAL HEALTH DILEMMA WITH HIGH MORBIDITY AND MORTALITY. HUMAN MALES ABSENT ON THE FIRST (HMOF) (A HISTONE ACETYLTRANSFERASE) IS RESPONSIBLE FOR DNA DAMAGE REPAIR, TUMORIGENESIS AND CELL CYCLE REGULATION. PERSISTENCE OF HBV DNA CONTRIBUTES TO CIRRHOSIS AND HEPATOCELLULAR CARCINOMA (HCC) IN CHB PATIENTS. HISTONE ACETYLTRANSFERASE ENHANCES HBV REPLICATION, HOWEVER THE PRECISE UNDERLYING MECHANISM OF HMOF IN HBV REPLICATION IN CHB PATIENTS REMAINS TO BE EXPLORED. THIS STUDY AIMS TO INVESTIGATE THE CORRELATION BETWEEN HEPATIC HMOF AND HBV DNA REPLICATION IN CHB PATIENTS, AND MAY PROVIDE NEW INSIGHTS TOWARDS THE TREATMENT OF CHB PATIENTS. METHODS: HMOF IN LIVER BIOPSY (CHB, N = 33 HBEAG(+); N = 20 HBEAG(-), AND THREE HEALTHY CONTROLS) WAS DETERMINED, USING IMMUNOHISTOCHEMISTRY, QPCR AND WESTERN BLOT. THE CORRELATION BETWEEN HMOF AND HBSAG, AS WELL AS, HBEAG WERE DETERMINED. RESULTS: A POSITIVE CORRELATION BETWEEN HMOF AND HBV DNA IN OVERALL CHB PATIENTS WAS OBSERVED. A DISTINCT POSITIVE CORRELATION BETWEEN HMOF AND HBSAG AND/OR HBEAG IN HBEAG(+) CHB PATIENTS WAS ALSO DETECTED, HOWEVER NOT OBSERVED BETWEEN HMOF AND HBSAG IN HBEAG(-) CHB PATIENTS. NO CORRELATION WAS OBSERVED BETWEEN HMOF AND HEPATIC INFLAMMATION SEVERITY AND FIBROTIC STAGE IN CHB PATIENTS. CONCLUSIONS: HEPATIC HMOF MIGHT CONTRIBUTE TO HOST HBV CLEARANCE IN CHB PATIENTS AND POSSIBLE PATHOGENESIS. 2018 2 3185 29 HBC BINDS TO THE CPG ISLANDS OF HBV CCCDNA AND PROMOTES AN EPIGENETIC PERMISSIVE STATE. HBV COVALENTLY CLOSED CIRCULAR DNA (CCCDNA) IS THE TEMPLATE FOR THE TRANSCRIPTION OF HBV. HBV CORE PROTEIN (HBC) IS A MAIN COMPONENT OF THE HBV CCCDNA MINICHROMOSOME. HOWEVER, THE FUNCTION OF HBC IN CCCDNA IS NOT FULLY UNDERSTOOD. IN LIGHT OF RECENT FINDINGS THAT HBV CCCDNA MAY BE REGULATED EPIGENETICALLY, WE ANALYZED THE BINDING OF HBC TO CCCDNA AND THE IMPACT OF HBC ON CCCDNA EPIGENETIC PROFILE IN THE LIVER BIOPSY SAMPLES OF 22 PATIENTS WITH CHRONIC HEPATITIS B (CHB). WE FOUND THAT HBC BINDING TO HBV CCCDNA OCCURRED PREFERENTIALLY AT CPG ISLAND 2, AN IMPORTANT REGION FOR THE REGULATION OF HBV TRANSCRIPTION. FURTHERMORE, THE RELATIVE ABUNDANCES OF HBC BINDING TO CPG ISLAND 2 WERE POSITIVELY CORRELATED WITH THE RATIOS OF RELAXED CIRCULAR DNA TO CCCDNA AND THE LEVELS OF SERUM HBV DNA IN THOSE PATIENTS. INTERESTINGLY, THE RELATIVE ABUNDANCES OF HBC BINDING TO CPG ISLAND 2 WERE ASSOCIATED WITH THE BINDING OF CREB BINDING PROTEIN (CBP) AND WITH HYPOMETHYLATION IN CPG ISLAND 2 OF HBV CCCDNA MINICHROMOSOMES. HOWEVER, RELATIVELY HIGHER AMOUNTS OF HBC BINDING TO CPG ISLAND 2 OF CCCDNA WERE ACCOMPANIED BY LOWER AMOUNTS OF HDAC1 BINDING. MULTIVARIATE ANALYSIS REVEALED THAT THE ABUNDANCES OF HBC BINDING TO CPG ISLAND 2 OF CCCDNA AND POSITIVE HBEAG WERE INDEPENDENT FACTORS ASSOCIATED WITH THE REPLICATION OF HBV (P = 0.001 FOR BOTH). APPARENTLY, HBC IS A POSITIVE REGULATOR OF HBV TRANSCRIPTION AND REPLICATION, MAINTAINING THE PERMISSIVE EPIGENETIC STATE IN THE CRITICAL REGION OF THE HBV CCCDNA MINICHROMOSOMES. 2011 3 1393 31 DIAGNOSTIC VALUE OF THE HYPOMETHYLATION OF THE WISP1 PROMOTER IN PATIENTS WITH HEPATOCELLULAR CARCINOMA ASSOCIATED WITH HEPATITIS B VIRUS. WNT1-INDUCIBLE SIGNALING PATHWAY PROTEIN 1 (WISP1) REGULATES CELL PROLIFERATION, DIFFERENTIATION, ADHESION, MIGRATION AND SURVIVAL. ABNORMAL WISP1 EXPRESSION IS ASSOCIATED WITH THE CARCINOGENESIS OF HEPATOCELLULAR CARCINOMA (HCC). ABERRANT DNA METHYLATION IS ONE OF THE MAJOR EPIGENETIC ALTERATIONS IN HCC. HOWEVER, THE METHYLATION STATUS OF THE WISP1 PROMOTER IS STILL UNCLEAR. WE THEREFORE AIMED TO DETERMINE THE METHYLATION STATUS OF THE WISP1 PROMOTER AND EVALUATE ITS CLINICAL VALUE IN HCC. THE STUDY ENROLLED 251 PARTICIPANTS, INCLUDING 123 PARTICIPANTS WITH HCC, 90 PARTICIPANTS WITH CHRONIC HEPATITIS B (CHB) AND 38 HEALTHY CONTROLS (HCS). WISP1 METHYLATION STATUS, MRNA LEVELS AND PLASMA SOLUBLE WISP1 WERE DETECTED BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP), QUANTITATIVE REAL-TIME PCR (RT-QPCR) AND ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA), RESPECTIVELY. WE FOUND THAT THE METHYLATION FREQUENCY OF WISP1 IN PATIENTS WITH HCC WAS SIGNIFICANTLY LOWER THAN THAT IN PATIENTS WITH CHB AND HCS, WHILE THE RELATIVE EXPRESSION LEVELS OF WISP1 MRNA WERE MARKEDLY HIGHER IN PATIENTS WITH HCC THAN IN PATIENTS WITH CHB AND HCS. FURTHERMORE, THE PLASMA SOLUBLE WISP1 IN PATIENTS WITH HCC WAS OBVIOUSLY LOWER THAN IN THAT IN PATIENTS WITH CHB AND HCS. ALPHA-FETOPROTEIN (AFP) IS A WIDELY RECOGNIZED BIOMARKER TO DIAGNOSE HCC WHICH LACKS ENOUGH SENSITIVITY AND SPECIFICITY. WISP1 PROMOTER METHYLATION STATUS COMBINED WITH AFP SIGNIFICANTLY IMPROVED THE DIAGNOSTIC ABILITY IN DISCRIMINATING HCC FROM CHB COMPARED WITH AFP OR WISP1 METHYLATION STATUS ALONE. IN CONCLUSION, HYPOMETHYLATION OF THE WISP1 GENE PROMOTER MAY SERVE AS A NONINVASIVE BIOMARKER FOR DETECTING HBV-ASSOCIATED HCC. 2020 4 3246 26 HEPATITIS B VIRUS (HBV) INDUCES THE EXPRESSION OF INTERLEUKIN-8 THAT IN TURN REDUCES HBV SENSITIVITY TO INTERFERON-ALPHA. HIGH LEVELS OF SERUM INTERLEUKIN-8 (IL-8) HAVE BEEN DETECTED IN CHRONIC HEPATITIS B (CHB) PATIENTS DURING EPISODES OF HEPATITIS FLARES. WE INVESTIGATED WHETHER HEPATITIS B VIRUS (HBV) MAY DIRECTLY INDUCE IL-8 PRODUCTION AND WHETHER IL-8 MAY ANTAGONIZE INTERFERON-ALPHA (IFN-ALPHA) ANTIVIRAL ACTIVITY AGAINST HBV. WE SHOWED THAT CHB PATIENTS HAD SIGNIFICANTLY HIGHER IL-8 LEVELS BOTH IN SERUM AND IN LIVER TISSUE THAN CONTROLS. IN HBV-REPLICATING HEPG2 CELLS, IL-8 TRANSCRIPTION WAS SIGNIFICANTLY ACTIVATED. AP-1, C/EBP AND NF-KB TRANSCRIPTION FACTORS WERE CONCURRENTLY NECESSARY FOR MAXIMUM IL-8 INDUCTION. MOREOVER, HBX VIRAL PROTEIN WAS RECRUITED ONTO THE IL-8 PROMOTER AND THIS WAS PARALLELED BY IL8-BOUND HISTONE HYPERACETYLATION AND BY ACTIVE RECRUITMENT OF TRANSCRIPTIONAL COACTIVATORS. INHIBITION OF IL-8 INCREASES THE ANTIVIRAL ACTIVITY OF IFN-ALPHA AGAINST HBV. OUR RESULTS INDICATE THAT HBV ACTIVATES IL-8 GENE EXPRESSION BY TARGETING THE EPIGENETIC REGULATION OF THE IL-8 PROMOTER AND THAT IL-8 MAY CONTRIBUTE TO REDUCE HBV SENSITIVITY TO IFN-ALPHA. 2013 5 4246 35 METHYLATION STATUS OF THE T-CADHERIN GENE PROMOTOR IN PERIPHERAL BLOOD MONONUCLEAR CELLS IS ASSOCIATED WITH HBV-RELATED HEPATOCELLULAR CARCINOMA PROGRESSION. DNA METHYLATION IS ONE OF THE EPIGENETIC MECHANISMS TO REGULATE GENE EXPRESSION AND FREQUENTLY OCCURS IN HUMAN CANCER CELLS. T-CADHERIN (CDH13) IS A NEW MEMBER OF THE CADHERIN SUPERFAMILY AND POSSESSES MULTIPLE FUNCTIONS. OUR STUDY INCLUDED 26 NORMAL CONTROLS (NCS), 65 CHRONIC HEPATITIS B PATIENTS (CHB), 14 LIVER CIRRHOSIS PATIENTS (LC) AND 157 HEPATOCELLULAR CARCINOMA PATIENTS (HCC). WE MAINLY FOCUSED ON THE MRNA EXPRESSION AND METHYLATION STATUS OF CDH13 IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS), WHICH WERE DETECTED BY SEMI-QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION (RT-QPCR) AND METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) RESPECTIVELY. THE CDH13 MRNA LEVEL WAS LOWER IN HCC, ESPECIALLY IN EARLY-STAGE OF HCC THAN IN NCS AND CHB GROUPS (P < 0.05). METHYLATION FREQUENCY OF THE CDH13 PROMOTER WAS SIGNIFICANTLY HIGHER IN HCC PATIENTS THAN IN THE NCS AND CHB GROUPS (67.52 % VS 0.00 %, P < 0.001, 67.52 % VS 52.31 %, P < 0.05, RESPECTIVELY). CDH13 MRNA LEVEL WAS SIGNIFICANTLY AND RELATIVELY LOWER IN METHYLATED GROUPS THAN IN UNMETHYLATED GROUPS AMONG THE WHOLE PARTICIPANTS. THE METHYLATION LEVEL OF CDH13 PROMOTER IN HCC MIGHT BE INFLUENCED OR PARTLY INFLUENCED BY SOME CRITICAL FACTORS SUCH AS TBIL, ALB AND AFP (P < 0.05). AS AN IMPORTANT FACTOR IN SIGNALING PATHWAY REGULATING BY CDH13 TO PROMOTE CARCINOGENESIS, JNK LEVEL WAS SIGNIFICANTLY HIGHER IN HCC WHICH HAD A HIGHER METHYLATION FREQUENCY THAN IN NCS, CHB AND LC (P < 0.05). FURTHERMORE, THE COMBINATION OF THE METHYLATED CDH13 LEVEL AND AFP LEVEL SHOWED A BETTER SCORE: AUC = 0.796 (SE = 0.031, 95 %CI 0.735-0.857; P < 0.001) IN MALE AND AUC = 0.832 (SE = 0.057, 95 %CI 0.721-0.944; P < 0.001) IN FEMALE COMPARED TO AFP ALONE FOR DIAGNOSING HCC FROM NCS, CHB AND LC. THE METHYLATION OF CDH13 PROMOTER WAS AN INDEPENDENT PREDICTOR FOR ASSESSING THE PROGNOSIS OF HCC PATIENTS (R=-1.378 P < 0.05). IN CONCLUSION, HYPERMETHYLATION OF CDH13 IN PBMCS WAS ASSOCIATED WITH THE UNDEREXPRESSION OF MRNA AND THE HIGH RISK OF HCC. THE METHYLATION STATUS OF THE CDH13 PROMOTER IN PBMCS WAS A POTENTIAL NONINVASIVE BIOMARKER TO PREDICT THE PROGNOSIS OF HCC PATIENTS. 2020 6 4239 32 METHYLATION PROFILE OF HEPATITIS B VIRUS IS NOT INFLUENCED BY INTERFERON ALPHA IN HUMAN LIVER CANCER CELLS. INTERFERON (IFN) ALPHA IS USED FOR THE TREATMENT OF CHRONIC HEPATITIS B VIRUS (HBV) INFECTION, BUT THE MOLECULAR MECHANISMS UNDERLYING ITS ANTIVIRAL EFFECT HAVE NOT BEEN FULLY ELUCIDATED. EPIGENETIC MODIFICATIONS REGULATE THE TRANSCRIPTIONAL ACTIVITY OF COVALENTLY CLOSED CIRCULAR DNA (CCCDNA) IN CELLS WITH CHRONIC HBV INFECTION. IFN?ALPHA HAS BEEN SHOWN TO MODIFY CCCDNA?BOUND HISTONES, BUT IT IS NOT KNOWN WHETHER THE ANTI?HBV EFFECT OF IFN?ALPHA INVOLVES METHYLATION OF CCCDNA. THE PRESENT STUDY AIMED TO DETERMINE WHETHER IFN?ALPHA INDUCED METHYLATION OF HBV CCCDNA IN A CELL?BASED MODEL IN WHICH HEPG2 CELLS WERE DIRECTLY INFECTED WITH WILD?TYPE HBV VIRIONS. METHYLATION STATUS OF HBV CCCDNA WAS ASSESSED USING GLOBAL DNA METHYLATION ELISA ASSAY, METHYLATION?SPECIFIC PCR AND BISULFITE SEQUENCING. IFN?ALPHA SUPPRESSED HBV DNA AND RNA TRANSCRIPTS, BUT METHYLATION PROFILES WERE SIMILAR BETWEEN THE CONTROL AND IFN?ALPHA TREATED GROUPS. CHROMATIN IMMUNOPRECIPITATION RESULTS REVEALED BINDING OF DNA METHYLTRANSFERASES (DNMT) 3A AND DNMT3B TO HBV CCCDNA AND TREATMENT WITH IFN?ALPHA SUPPRESSED THE RECRUITMENT OF DNMT3B TO CCCDNA. TAKEN TOGETHER, THESE RESULTS SUGGEST THAT IFN?ALPHA DOES NOT INDUCE METHYLATION OF HBV CCCDNA. THEREFORE, IT WAS CONCLUDED THAT METHYLATION IS UNLIKELY TO CONTRIBUTE TO THE ANTI?HBV EFFECT OF IFN?ALPHA IN HEPG2 CELLS, AND THAT ALTERNATIVE MECHANISMS NEED TO BE SOUGHT TO ENHANCE CCCDNA METHYLATION AS A NOVEL THERAPY AGAINST HBV. 2021 7 3448 28 HYPERMETHYLATION OF THE N-MYC DOWNSTREAM-REGULATED GENE 2 PROMOTER IN PERIPHERAL BLOOD MONONUCLEAR CELLS IS ASSOCIATED WITH LIVER FIBROSIS IN CHRONIC HEPATITIS B. DNA METHYLATION IS A FUNDAMENTAL EPIGENETIC MODIFICATION TO REGULATE GENE EXPRESSION. N-MYC DOWNSTREAM-REGULATED GENE (NDRG) 2 IS A CYTOPLASMIC PROTEIN AND PARTICIPATES IN THE PATHOGENESIS OF LIVER FIBROSIS. IN THIS STUDY, THE MRNA EXPRESSION AND METHYLATION STATUS OF NDRG2 WAS EVALUATED IN PATIENTS WITH CHRONIC HEPATITIS B (CHB). THE STUDY INCLUDED 143 CHB PATIENTS AND 65 NORMAL CONTROLS (NC). THE MRNA EXPRESSION OF NDRG2 IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) WAS DETECTED BY QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION. THE METHYLATION STATUS OF THE NDRG2 PROMOTER IN PBMCS WAS DETECTED BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION. THE NDRG2 MRNA LEVEL WAS LOWER IN THE CHB GROUP THAN IN THE NC GROUP (P < 0.001). METHYLATION FREQUENCY OF THE NDRG2 PROMOTER WAS SIGNIFICANTLY HIGHER IN CHB PATIENTS THAN IN THE NC GROUP (52.44% VS. 26.15%, P < 0.001). IMPORTANTLY, THE RELATIVE EXPRESSION LEVELS OF NDRG2 MRNA WERE SIGNIFICANTLY LOWER IN THE METHYLATED GROUP THAN IN THE UNMETHYLATED GROUP IN BOTH CHB PATIENTS AND NC (P < 0.001). FURTHERMORE, A LOWER MRNA LEVEL AND HYPERMETHYLATION OF NDRG2 WERE ASSOCIATED WITH LIVER FIBROSIS AND INFLAMMATION GRADE IN CHB. THE ASPARTATE AMINOTRANSFERASE-TO-PLATELET RATIO INDEX (APRI) SCORE IS WIDELY USED TO PREDICT LIVER FIBROSIS. THE MRNA EXPRESSION LEVELS AND METHYLATION STATUS OF NDRG2 SHOWED A BETTER SCORE COMPARED TO APRI FOR DISCRIMINATING THE SEVERITY OF LIVER FIBROSIS. IN CONCLUSION, HYPERMETHYLATION OF NDRG2 IN PBMCS WAS CORRELATED WITH DECREASED MRNA EXPRESSION AND WITH LIVER FIBROSIS. THE METHYLATION STATUS OF THE NDRG2 PROMOTER IN PBMCS IS A POTENTIAL NONINVASIVE BIOMARKER TO PREDICT THE SEVERITY OF LIVER FIBROSIS. 2017 8 4903 28 P16 PROMOTER HYPERMETHYLATION IN HUMAN HEPATOCELLULAR CARCINOMA WITH OR WITHOUT HEPATITIS VIRUS INFECTION. BACKGROUND: EPIGENETIC ALTERATION THROUGH METHYLATION IS ONE OF THE MOST IMPORTANT STEPS IN CARCINOGENESIS. HOWEVER, THE RELATION BETWEEN HEPATITIS VIRUS INFECTION AND EPIGENETIC ALTERATIONS IS POORLY UNDERSTOOD. METHODS: SIXTEEN PATIENTS WITHOUT HEPATITIS B VIRUS (HBV) AND HEPATITIS C VIRUS (HCV) AND 35 PATIENTS WITH HBV OR HCV WHO UNDERWENT LIVER RESECTION FOR HEPATOCELLULAR CARCINOMA (HCC) WERE STUDIED. MUTATION OF P53 WAS DETECTED BY DIRECT SEQUENCING. METHYLATION STATUS OF P16 WAS EVALUATED IN TUMOR AND NONCANCEROUS LIVER TISSUES BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION. RESULTS: IN HCC WITHOUT HBV AND HCV, P53 MUTATIONS WERE DETECTED IN 5 (31%) OF 16 HCCS. METHYLATION OF P16 PROMOTER WAS DETECTED IN 2 (25%) OF 8 MODERATELY DIFFERENTIATED HCCS, 6 (75%) OF 8 POORLY DIFFERENTIATED HCCS, AND NONE OF 16 NONCANCEROUS TISSUE SPECIMENS. IN HCC WITH HBV OR HCV, P53 MUTATIONS WERE DETECTED IN 8 (23%) OF 35 HCCS. METHYLATION OF P16 PROMOTER WAS DETECTED IN 2 (100%) OF 2 WELL-DIFFERENTIATED HCCS, 13 (76%) OF 17 MODERATELY DIFFERENTIATED HCCS, 12 (75%) OF 16 POORLY DIFFERENTIATED HCCS, AND 9 (26%) OF 35 NONCANCEROUS LIVER TISSUE SPECIMENS. CONCLUSIONS: OUR RESULTS SUGGEST THAT HEPATITIS VIRUSES MIGHT INDUCE METHYLATION OF P16 PROMOTER IN LIVER WITH CHRONIC INFLAMMATION, BEFORE APPEARANCE OF HCC. 2004 9 2759 35 EXPRESSION OF IL-17 AND ITS GENE PROMOTER METHYLATION STATUS ARE ASSOCIATED WITH THE PROGRESSION OF CHRONIC HEPATITIS B VIRUS INFECTION. TO EXPLORE INTERLEUKIN-17 (IL-17) AND ITS EPIGENETIC REGULATION DURING THE PROGRESSION OF CHRONIC HEPATITIS B VIRUS (HBV) INFECTION.A TOTAL OF 162 PATIENTS WITH CHRONIC HBV INFECTION, INCLUDING 75 WITH CHRONIC HEPATITIS B (CHB), 54 WITH HEPATITIS B-ASSOCIATED LIVER CIRRHOSIS AND 33 WITH HEPATITIS B-ASSOCIATED HEPATOCELLULAR CARCINOMA (HBV-HCC), WERE ENROLLED IN THIS STUDY. THIRTY HEALTHY ADULTS OF THE SAME ETHNICITY WERE ENROLLED IN THE CONTROL GROUP. WHOLE VENOUS BLOOD WAS OBTAINED FROM THE PATIENTS AND NORMAL CONTROLS (N = 30). CLINICAL AND LABORATORY PARAMETERS WERE ASSESSED, AND WE PERFORMED ENZYME-LINKED IMMUNOSORBENT ASSAY AND QUANTITATIVE REAL-TIME PCR TO MEASURE THE SERUM LEVELS AND RELATIVE MRNA EXPRESSION OF IL-17, RESPECTIVELY. IL-17 PROMOTER METHYLATION IN PERIPHERAL BLOOD MONONUCLEAR CELLS WAS ASSESSED BY METHYLATION-SPECIFIC PCR. WE ANALYZED THE SERUM AND MRNA LEVELS OF IL-17 AND IL-17 PROMOTER METHYLATION IN THE 4 GROUPS AS WELL AS THE EFFECT OF METHYLATION ON SERUM IL-17 LEVELS. CORRELATIONS BETWEEN THE IL-17 PROMOTER METHYLATION STATUS AND CLINICAL PARAMETERS WERE ANALYZED BY SPEARMAN CORRELATION ANALYSIS.COMPARED TO THE NORMAL CONTROL GROUP, THE PATIENT GROUPS EXHIBITED SIGNIFICANTLY HIGHER SERUM AND RELATIVE MRNA LEVELS OF IL-17. THE METHYLATION DISTRIBUTION AMONG THE PATIENTS WAS SIGNIFICANTLY LOWER THAN THAT AMONG THE NORMAL CONTROLS (P < .05), WITH THE HBV-HCC GROUP SHOWING THE LOWEST IL-17 GENE METHYLATION FREQUENCY. THE AVERAGE IL-17 PROMOTER CG METHYLATION LEVEL WAS NEGATIVELY CORRELATED WITH IL-17 MRNA EXPRESSION (R = -0.39, P = .03), AND NEGATIVE CORRELATIONS BETWEEN IL-17 PROMOTER METHYLATION AND PROTHROMBIN TIME ACTIVITY (R = -0.585, P = .035), ALANINE AMINOTRANSFERASE (R = -0.522, P < .01), ASPARTATE AMINOTRANSFERASE (R = -0.315, P < .05), AND THE MODEL FOR END-STAGE LIVER DISEASE SCORE (R = -0.461, P < .05) WERE OBSERVED. IL-17 SERUM LEVELS IN THE METHYLATED-PROMOTER GROUPS WERE SIGNIFICANTLY LOWER THAN THOSE IN THE UNMETHYLATED-PROMOTER GROUPS.IL-17 EXPRESSION AND PROMOTER METHYLATION WERE ASSOCIATED WITH CHRONIC HBV INFECTION PROGRESSION, ESPECIALLY IN THE HBV-HCC GROUP. THE IL-17 PROMOTER STATUS MAY HELP CLINICIANS INITIATE THE CORRECT TREATMENT STRATEGY AT THE CHB STAGE. 2019 10 4220 31 METHYLATED CYSTEINE DIOXYGENASE-1 GENE PROMOTER IN THE SERUM IS A POTENTIAL BIOMARKER FOR HEPATITIS B VIRUS-RELATED HEPATOCELLULAR CARCINOMA. HEPATOCELLULAR CARCINOMA (HCC) IS THE THIRD LEADING CAUSE OF CANCER-RELATED MORTALITY WORLDWIDE. EPIGENETIC ANALYSIS HAS ATTRACTED INCREASING ATTENTION IN THE MOLECULAR DIAGNOSIS OF HCC. CYSTEINE DIOXYGENASE 1 (CDO1) IS A KEY ENZYME IN THE TAURINE BIOSYNTHETIC PATHWAY AND CONVERTS CYSTEINE TO CYSTEINE SULFINATE. THE CDO1 GENE IS A TUMOR SUPPRESSOR GENE AND IS USUALLY SILENCED BY THE METHYLATION OF ITS PROMOTER IN CARCINOGENESIS. IN THIS STUDY, WE EVALUATED WHETHER THE METHYLATION STATUS OF CDO1 GENE PROMOTER IS OF DIAGNOSTIC VALUE FOR HEPATITIS B VIRUS (HBV)-RELATED HCC. THE CDO1 PROMOTER METHYLATION STATUS WAS DETERMINED IN SERUM SAMPLES USING METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) IN A COHORT OF 123 PATIENTS WITH HBV-RELATED HCC, 28 WITH LIVER CIRRHOSIS (LC), 29 WITH CHRONIC HEPATITIS B (CHB) AND 20 HEALTHY CONTROLS. THE FREQUENCY OF THE CDO1 PROMOTER METHYLATION IN HBV-RELATED HCC (42.3%) WAS SIGNIFICANTLY HIGHER THAN THAT IN LC (14.3%), CHB (6.9%) AND HEALTHY CONTROLS (0%) (P = 0.006; P < 0.0001; P < 0.0001; RESPECTIVELY). FURTHERMORE, IN HCC PATIENTS, THE FREQUENCY OF CDO1 PROMOTER METHYLATION WAS HIGHER IN ADVANCED STAGES (III-IV) (53%) THAN THE EARLY STAGES (I-II) (20%) (P = 0.001). EVALUATION OF THE CDO1 PROMOTER METHYLATION STATUS IN SERUM, IN COMBINATION WITH AFP (> 20 NG/ML), SIGNIFICANTLY IMPROVED THE DIAGNOSTIC VALUE, WITH SENSITIVITY AND SPECIFICITY OF 82.9% AND 75.4%, RESPECTIVELY IN DISTINGUISHING HCC FROM LC AND CHB. IN CONCLUSION, METHYLATION STATUS OF SERUM CDO1 GENE PROMOTER MAY BE HELPFUL IN THE DIAGNOSIS OF HCC AND THE ESTIMATION OF THE HCC STAGES. 2014 11 3186 35 HBV COVALENTLY CLOSED CIRCULAR DNA MINICHROMOSOMES IN DISTINCT EPIGENETIC TRANSCRIPTIONAL STATES DIFFER IN THEIR VULNERABILITY TO DAMAGE. BACKGROUND AND AIMS: HBV COVALENTLY CLOSED CIRCULAR DNA (CCCDNA) IS A MAJOR OBSTACLE FOR A CURE OF CHRONIC HEPATITIS B. ACCUMULATING EVIDENCE SUGGESTS THAT EPIGENETIC MODIFICATIONS REGULATE THE TRANSCRIPTIONAL ACTIVITY OF CCCDNA MINICHROMOSOMES. HOWEVER, IT REMAINS UNCLEAR HOW THE EPIGENETIC STATE OF CCCDNA AFFECTS ITS STABILITY. APPROACHES AND RESULTS: BY USING HBV INFECTION CELL MODELS AND IN VITRO AND IN VIVO RECOMBINANT CCCDNA (RCCCDNA) AND HBVCIRCLE MODELS, THE REDUCTION RATE OF HBV CCCDNA AND THE EFFICACY OF APOLIPOPROTEIN B MRNA EDITING ENZYME CATALYTIC SUBUNIT 3A (APOBEC3A)-MEDIATED AND CRISPR/CRISPR-ASSOCIATED 9 (CAS9)-MEDIATED CCCDNA TARGETING WERE COMPARED BETWEEN CCCDNAS WITH DISTINCT TRANSCRIPTIONAL ACTIVITIES. INTERFERON-ALPHA TREATMENT AND HEPATITIS B X PROTEIN (HBX) DELETION WERE APPLIED AS TWO STRATEGIES FOR CCCDNA REPRESSION. CHROMATIN IMMUNOPRECIPITATION AND MICROCOCCAL NUCLEASE ASSAYS WERE PERFORMED TO DETERMINE THE EPIGENETIC PATTERN OF CCCDNA. HBV CCCDNA LEVELS REMAINED STABLE IN NONDIVIDING HEPATOCYTES; HOWEVER, THEY WERE SIGNIFICANTLY REDUCED DURING CELL DIVISION, AND THE REDUCTION RATE WAS SIMILAR BETWEEN CCCDNAS IN TRANSCRIPTIONALLY ACTIVE AND TRANSCRIPTIONALLY REPRESSED STATES. STRIKINGLY, HBV RCCCDNA WITHOUT HBX EXPRESSION EXHIBITED A SIGNIFICANTLY LONGER PERSISTENCE IN MICE. THE CCCDNA WITH LOW TRANSCRIPTIONAL ACTIVITY EXHIBITED AN EPIGENETICALLY INACTIVE PATTERN AND WAS MORE DIFFICULT TO ACCESS BY APOBEC3A AND ENGINEERED CRISPR-CAS9. THE EPIGENETIC REGULATOR ACTIVATING CCCDNA INCREASED ITS VULNERABILITY TO APOBEC3A. CONCLUSIONS: HBV CCCDNA MINICHROMOSOMES IN DISTINCT EPIGENETIC TRANSCRIPTIONAL STATES SHOWED A SIMILAR REDUCTION RATE DURING CELL DIVISION BUT SIGNIFICANTLY DIFFERED IN THEIR ACCESSIBILITY AND VULNERABILITY TO TARGETED NUCLEASES AND ANTIVIRAL AGENTS. EPIGENETIC SENSITIZATION OF CCCDNA MAKES IT MORE SUSCEPTIBLE TO DAMAGE AND MAY POTENTIALLY CONTRIBUTE TO AN HBV CURE. 2022 12 3453 36 HYPOMETHYLATED UBIQUITIN-CONJUGATING ENZYME2 Q1 (UBE2Q1) GENE PROMOTER IN THE SERUM IS A PROMISING BIOMARKER FOR HEPATITIS B VIRUS-ASSOCIATED HEPATOCELLULAR CARCINOMA. ABERRANT DNA METHYLATION, WHICH CAN BE DETECTED IN CIRCULATING CELL-FREE DNA (CFDNA), IS ONE OF THE MAJOR EPIGENETIC ALTERATIONS IN HEPATOCELLULAR CARCINOMA (HCC). UBE2Q1, A PUTATIVE MEMBER OF THE UBIQUITIN-CONJUGATING ENZYME FAMILY, MIGHT PLAY SUBSTANTIAL ROLES IN TUMORIGENESIS. HOWEVER, THE METHYLATION STATUS OF THE UBE2Q1 GENE IN HCC REMAINS UNKNOWN. WE AIMED TO DETERMINE THE METHYLATION STATUS OF THE UBE2Q1 GENE PROMOTER AND TO EVALUATE ITS POTENTIAL CLINICAL SIGNIFICANCE FOR HCC DETECTION. THE METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) ASSAY WAS USED TO DETECT THE UBE2Q1 GENE METHYLATION STATUS IN SERUM SAMPLES FROM 80 PATIENTS WITH HEPATITIS B VIRUS (HBV)-RELATED HCC, 40 PATIENTS WITH LIVER CIRRHOSIS (LC), 40 PATIENTS WITH CHRONIC HEPATITIS B (CHB), AND 20 HEALTHY CONTROLS (HCS). SIGNIFICANTLY LOWER METHYLATION FREQUENCIES WERE DETECTED IN HCC PATIENTS (33.75%) COMPARED WITH LC PATIENTS (55.00%, P = 0.026) AND CHB PATIENTS (60.00%, P = 0.006) AND HCS (65.00%, P = 0.011). HYPOMETHYLATION OF THE UBE2Q1 GENE WAS NEGATIVELY ASSOCIATED WITH THE TUMOR NODE METASTASIS STAGE (R(S) = -0.30, P = 0.008). THE UBE2Q1 GENE METHYLATION STATUS COMBINED WITH ALPHA FETOPROTEIN USING CUT-OFF POINTS OF 20, 200 AND 400 NG/ML SHOWED SENSITIVITY AND SPECIFICITY VALUES OF 58.8% AND 75.0%, 53.8% AND 87.5%, AND 37.5% AND 88.7%, RESPECTIVELY, AND YIELDED A SIGNIFICANTLY INCREASED AREA UNDER THE ROC CURVE (0.720, 0.760 AND 0.694, RESPECTIVELY) FOR DISCRIMINATING HCC FROM LC AND CHB. OUR STUDY RESULTS SUGGEST THAT HYPOMETHYLATION OF THE UBE2Q1 GENE PROMOTER IS A POTENTIAL BIOMARKER FOR DETECTING HBV-ASSOCIATED HCC. 2017 13 3794 32 INTERLEUKIN-33 MEDIATES BOTH IMMUNE-RELATED AND NON-IMMUNE-RELATED INHIBITORY EFFECTS AGAINST HEPATITIS B VIRUS. CHRONIC INFECTION BY HEPATITIS B VIRUS (HBV) IS ASSOCIATED WITH HIGH RISKS OF LIVER FIBROSIS, CIRRHOSIS AND HEPATOCELLULAR CARCINOMA. HBV COVALENTLY CLOSED CIRCULAR DNA (CCCDNA) IN THE NUCLEUS OF INFECTED HEPATOCYTE SERVES AS TRANSCRIPTION TEMPLATE. NEITHER NATURAL RESOLUTION OF ACUTE INFECTION NOR CURRENT TREATMENT OPTIONS FOR CHRONIC INFECTION ARE BELIEVED TO CAUSE CCCDNA CLEARANCE. WE PREVIOUSLY SHOWED THAT INJECTION OF IL-33-EXPRESSING PLASMID FACILITATED CLEARANCE OF INTRAHEPATIC HBV DNA IN A MOUSE MODEL OF HBV PERSISTENCE. IN THIS WORK, HBV-TARGETING THERAPEUTIC EFFECTS OF IL-33 WERE FURTHER EXPLORED. MURINE IL-33 DELIVERED BY RECOMBINANT ADENO-ASSOCIATED VIRUS (AAV-MIL-33) INDUCED CLEARANCE OF BOTH SERUM HBV MARKERS AND INTRAHEPATIC HBV DNA IN TWO MOUSE MODELS OF HBV PERSISTENCE BASED ON REPLICON PLASMID AND RECOMBINANT CCCDNA (RCCCDNA) RESPECTIVELY. CLEARANCE WAS ASSOCIATED WITH SERUM ALT ELEVATIONS AND LIVER INFILTRATIONS BY CD4(+) AND CD8(+) T CELLS, INDICATING IL-33-INDUCED CELLULAR IMMUNE RESPONSES AGAINST HBV-HARBORING CELLS. ADOPTIVE TRANSFER OF SPLENOCYTES FROM AAV-MIL-33-CURED MICE WAS INDEED SUFFICIENT TO ENGENDER SIMILAR CLEARANCE IN RECIPIENT MICE. IN VITRO, INTRACELLULAR, INSTEAD OF EXTRACELLULAR, IL-33 WAS MAINLY RESPONSIBLE FOR REPRESSING VIRAL TRANSCRIPTION, PROTEIN PRODUCTION AND GENOME REPLICATION IN HUH7 CELLS TRANSFECTED WITH HBV REPLICON OR RCCCDNA. IL-33 WAS SHOWN TO BE RECRUITED ONTO RCCCDNA MINICHROMOSOME ACCOMPANIED BY LOSS OF TRANSCRIPTIONAL ACTIVATION EPIGENETIC MARKS. FINALLY, TRANSFECTION OF IL-33 INTO HBV-INFECTED HEPG2/NTCP CELLS RESULTED IN REDUCED TRANSCRIPTION, ANTIGEN EXPRESSION AND GENOME REPLICATION, SUGGESTING REPRESSION OF CANONICAL CCCDNA. THESE DATA DEMONSTRATED DIVERSE INHIBITORY EFFECTS ON HBV AND HBV-INFECTED CELLS MEDIATED BY IL-33, AND SUGGEST IL-33 AS AN INTERESTING THERAPEUTIC CANDIDATE. 2022 14 1192 30 CORRELATION OF CPG METHYLATION OF THE PDCD1 GENE WITH PD-1 EXPRESSION ON CD8(+) T CELLS AND MEDICAL LABORATORY INDICATORS IN CHRONIC HEPATITIS B INFECTION. BACKGROUND: THE NEGATIVE SIGNAL PROVIDED BY SOME CO-INHIBITORY FACTORS SUCH AS PROGRAMMED CELL DEATH-1 (PD-1) HAS BEEN ASSOCIATED WITH CHRONIC HEPATITIS B (CHB) INFECTION INDUCED-T CELL EXHAUSTION, ALTHOUGH THE CORRELATION OF CPG METHYLATION OF THE PDCD1 GENE WITH PD-1 EXPRESSION AND MEDICAL LABORATORY INDICATORS IN CHB INFECTION HAS NOT YET BEEN ELUCIDATED. METHODS: BLOOD SAMPLES FROM 20 CHB INFECTION PATIENTS AND 20 SPONTANEOUS CLEARANCE (SC) PATIENTS WERE COLLECTED. PERCENTAGES OF PD-1-POSITIVE CD8(+) T CELLS WERE ANALYZED BY FLOW CYTOMETRY. THE PERCENTAGE OF CPG METHYLATION AT THE PDCD1 LOCUS WAS ANALYZED BY BISULFITE SEQUENCING. STUDENT'S T TEST, PEARSON AND SPEARMAN'S CORRELATION, AND MANN-WHITNEY TESTS WERE USED IN THE STATISTICAL ANALYSIS. RESULTS: PERCENTAGES OF PD-1-POSITIVE CD8(+) T CELLS IN PERIPHERAL BLOOD T CELLS WERE SIGNIFICANTLY HIGHER IN CHB PATIENTS THAN IN THE SC GROUP (P < 0.001). THE METHYLATION LEVEL OF PDCD1 WAS SIGNIFICANTLY LOWER IN CHB PATIENTS (P < 0.001) AND THE METHYLATION LEVEL OF PDCD1 WAS NEGATIVELY CORRELATED WITH PD-1 EXPRESSION LEVEL IN CD8(+) T CELLS (P < 0.001) AND HEPATITIS-B SURFACE ANTIGEN (HBSAG) (P < 0.001). CONCLUSIONS: THE RESULTS OF THE PRESENT STUDY SUGGEST THAT PDCD1 METHYLATION IS CORRELATED WITH PD-1 EXPRESSION ON CD8(+) T CELLS AND CORRELATED WITH HBSAG AND ALANINE AMINOTRANSFERASE. THE RESULTS MAY PROVIDE NEW IDEAS REGARDING ANTI-PD-1 INHIBITORS, AND EPIGENETIC REGULATORS SUCH AS DEMETHYLATION INHIBITORS COULD REPRESENT MORE SUCCESSFUL THERAPEUTIC STRATEGIES IN HEPATITIS B INFECTION PATIENTS. 2020 15 2837 38 FORKHEAD O TRANSCRIPTION FACTOR 4 RESTRICTS HBV COVALENTLY CLOSED CIRCULAR DNA TRANSCRIPTION AND HBV REPLICATION THROUGH GENETIC DOWNREGULATION OF HEPATOCYTE NUCLEAR FACTOR 4 ALPHA AND EPIGENETIC SUPPRESSION OF COVALENTLY CLOSED CIRCULAR DNA VIA INTERACTING WITH PROMYELOCYTIC LEUKEMIA PROTEIN. NUCLEAR LOCATED HEPATITIS B VIRUS (HBV) COVALENTLY CLOSED CIRCULAR DNA (CCCDNA) REMAINS THE KEY OBSTACLE TO CURE CHRONIC HEPATITIS B (CHB). IN OUR PREVIOUS INVESTIGATION, IT WAS FOUND THAT FOXO4 COULD INHIBIT HBV CORE PROMOTER ACTIVITY THROUGH DOWNREGULATING THE EXPRESSION OF HNF4ALPHA. HOWEVER, THE EXACT MECHANISMS WHEREBY FOXO4 INHIBITS HBV REPLICATION, ESPECIALLY ITS EFFECT ON CCCDNA, REMAIN UNCLEAR. HERE, OUR DATA FURTHER REVEALED THAT FOXO4 COULD EFFECTIVELY INHIBIT CCCDNA MEDIATED TRANSCRIPTION AND HBV REPLICATION WITHOUT AFFECTING CCCDNA LEVEL. MECHANISTIC STUDY SHOWED THAT FOXO4 COULD CAUSE EPIGENETIC SUPPRESSION OF CCCDNA. ALTHOUGH FOXO4-MEDIATED DOWNREGULATION OF HNF4ALPHA CONTRIBUTED TO INHIBITING HBV CORE PROMOTER ACTIVITY, IT HAD LITTLE EFFECT ON CCCDNA EPIGENETIC REGULATION. FURTHER, IT WAS FOUND THAT FOXO4 COULD COLOCALIZE WITHIN PROMYELOCYTIC LEUKEMIA PROTEIN (PML) NUCLEAR BODIES AND INTERACT WITH PML. OF NOTE, PML WAS REVEALED TO BE CRITICAL FOR FOXO4-MEDIATED INHIBITION OF CCCDNA EPIGENETIC MODIFICATION AND OF THE FOLLOWING CCCDNA TRANSCRIPTION AND HBV REPLICATION. FURTHERMORE, FOXO4 WAS FOUND TO BE DOWNREGULATED IN HBV-INFECTED HEPATOCYTES AND HUMAN LIVER TISSUES, AND IT WAS NEGATIVELY CORRELATED WITH CCCDNA TRANSCRIPTIONAL ACTIVITY IN CHB PATIENTS. TOGETHER, THESE FINDINGS HIGHLIGHT THE ROLE OF FOXO4 IN SUPPRESSING CCCDNA TRANSCRIPTION AND HBV REPLICATION VIA GENETIC DOWNREGULATION OF HNF4ALPHA AND EPIGENETIC SUPPRESSION OF CCCDNA THROUGH INTERACTING WITH PML. TARGETING FOXO4 MAY PRESENT AS A NEW THERAPEUTIC STRATEGY AGAINST CHRONIC HBV INFECTION. IMPORTANCE HBV CCCDNA IS A DETERMINING FACTOR FOR VIRAL PERSISTENCE AND THE MAIN OBSTACLE FOR A CURE OF CHRONIC HEPATITIS B. STRATEGIES THAT TARGET CCCDNA DIRECTLY ARE THEREFORE OF GREAT IMPORTANCE IN CONTROLLING PERSISTENT HBV INFECTION. IN PRESENT INVESTIGATION, WE FOUND THAT FOXO4 COULD EFFICIENTLY SUPPRESS CCCDNA TRANSCRIPTION AND HBV REPLICATION WITHOUT AFFECTING THE LEVEL OF CCCDNA ITSELF. FURTHER, OUR DATA REVEALED THAT FOXO4 MIGHT INHIBIT CCCDNA FUNCTION VIA A TWO-PART MECHANISM: ONE IS TO EPIGENETICALLY SUPPRESS CCCDNA TRANSCRIPTION VIA INTERACTING WITH PML, AND THE OTHER IS TO INHIBIT HBV CORE PROMOTER ACTIVITY VIA THE GENETIC DOWNREGULATION OF HNF4ALPHA. OF NOTE, HBV MIGHT DAMPEN THE EXPRESSION OF FOXO4 FOR ITS OWN PERSISTENT INFECTION. WE PROPOSE THAT MANIPULATION OF FOXO4 MAY PRESENT AS A POTENTIAL THERAPEUTIC STRATEGY AGAINST CHRONIC HBV INFECTION. 2022 16 5335 29 QUANTIFICATION AND EPIGENETIC EVALUATION OF THE RESIDUAL POOL OF HEPATITIS B COVALENTLY CLOSED CIRCULAR DNA IN LONG-TERM NUCLEOSIDE ANALOGUE-TREATED PATIENTS. HEPATITIS B VIRUS (HBV) COVALENTLY CLOSED CIRCULAR (CCC)DNA IS THE KEY GENOMIC FORM RESPONSIBLE FOR VIRAL PERSISTENCE AND VIROLOGICAL RELAPSE AFTER TREATMENT WITHDRAWAL. THE ASSESSMENT OF RESIDUAL INTRAHEPATIC CCCDNA LEVELS AND ACTIVITY AFTER LONG-TERM NUCLEOS(T)IDE ANALOGUES THERAPY STILL REPRESENTS A TECHNICAL CHALLENGE. QUANTITATIVE (Q)PCR, ROLLING CIRCLE AMPLIFICATION (RCA) AND DROPLET DIGITAL (DD)PCR ASSAYS WERE USED TO QUANTIFY RESIDUAL INTRAHEPATIC CCCDNA IN LIVER BIOPSIES FROM 56 CHRONICALLY HBV INFECTED PATIENTS AFTER 3 TO 5 YEARS OF TELBIVUDINE TREATMENT. ACTIVITY OF RESIDUAL CCCDNA WAS EVALUATED BY QUANTIFYING 3.5 KB HBV RNA (PREC/PGRNA) AND BY ASSESSING CCCDNA-ASSOCIATED HISTONE TAILS POST-TRANSCRIPTIONAL MODIFICATIONS (PTMS) BY MICRO-CHROMATIN IMMUNOPRECIPITATION. LONG-TERM TELBIVUDINE TREATMENT RESULTED IN SERUM HBV DNA SUPPRESSION, WITH MOST OF THE PATIENTS REACHING UNDETECTABLE LEVELS. DESPITE 38 OUT OF 56 PATIENTS HAD UNDETECTABLE CCCDNA WHEN ASSESSED BY QPCR, RCA AND DDPCR ASSAYS DETECTED CCCDNA IN ALL-BUT-ONE NEGATIVE SAMPLES. LOW PREC/PGRNA LEVEL IN TELBIVUDINE-TREATED SAMPLES WAS ASSOCIATED WITH ENRICHMENT FOR CCCDNA HISTONE PTMS RELATED TO REPRESSED TRANSCRIPTION. NO DIFFERENCE IN CCCDNA LEVELS WAS FOUND ACCORDING TO SERUM VIRAL MARKERS EVOLUTION. THIS PANEL OF CCCDNA EVALUATION TECHNIQUES SHOULD PROVIDE AN ADDED VALUE FOR THE NEW PROOF-OF-CONCEPT CLINICAL TRIALS AIMING AT A FUNCTIONAL CURE OF CHRONIC HEPATITIS B. 2020 17 442 24 ANTIVIRAL THERAPIES FOR HEPATITIS B VIRUS-RELATED HEPATOCELLULAR CARCINOMA. CHRONIC HEPATITIS B VIRUS (HBV) INFECTION IS A CRITICAL RISK FACTOR FOR THE CARCINOGENESIS AND PROGRESSION OF HEPATOCELLULAR CARCINOMA (HCC). IT PROMOTES HCC DEVELOPMENT BY INDUCING LIVER FIBROGENESIS, GENETIC AND EPIGENETIC ALTERATIONS, AND THE EXPRESSION OF ACTIVE VIRAL-CODED PROTEINS. EFFECTIVE ANTIVIRAL TREATMENTS INHIBIT THE REPLICATION OF HBV, REDUCE SERUM VIRAL LOAD AND ACCELERATE HEPATITIS B E ANTIGEN SERUM CONVERSION. TIMELY INITIATION OF ANTIVIRAL TREATMENT IS NOT ONLY ESSENTIAL FOR PREVENTING THE INCIDENCE OF HCC IN CHRONIC HEPATITIS B PATIENTS, BUT ALSO IMPORTANT FOR REDUCING HBV REACTIVATION, IMPROVING LIVER FUNCTION, REDUCING OR DELAYING HCC RECURRENCE, AND PROLONGING OVERALL SURVIVAL OF HBV-RELATED HCC PATIENTS AFTER CURATIVE AND PALLIATIVE THERAPIES. THE SELECTION OF ANTIVIRAL DRUGS, MONITORING OF INDICATORS SUCH AS HBV DNA AND HEPATITIS B SURFACE ANTIGEN, AND TIMELY RESCUE TREATMENT WHEN NECESSARY, ARE ESSENTIAL IN ANTIVIRAL THERAPIES FOR HBV-RELATED HCC. 2015 18 5715 34 SIRT3 RESTRICTS HEPATITIS B VIRUS TRANSCRIPTION AND REPLICATION THROUGH EPIGENETIC REGULATION OF COVALENTLY CLOSED CIRCULAR DNA INVOLVING SUPPRESSOR OF VARIEGATION 3-9 HOMOLOG 1 AND SET DOMAIN CONTAINING 1A HISTONE METHYLTRANSFERASES. HEPATITIS B VIRUS (HBV) INFECTION REMAINS A MAJOR HEALTH PROBLEM WORLDWIDE. MAINTENANCE OF THE COVALENTLY CLOSED CIRCULAR DNA (CCCDNA), WHICH SERVES AS A TEMPLATE FOR HBV RNA TRANSCRIPTION, IS RESPONSIBLE FOR THE FAILURE OF ERADICATING CHRONIC HBV DURING CURRENT ANTIVIRAL THERAPY. CCCDNA IS ASSEMBLED WITH CELLULAR HISTONE PROTEINS INTO CHROMATIN, BUT LITTLE IS KNOWN ABOUT THE REGULATION OF HBV CHROMATIN BY HISTONE POSTTRANSLATIONAL MODIFICATIONS. IN THIS STUDY, WE IDENTIFIED SILENT MATING TYPE INFORMATION REGULATION 2 HOMOLOG 3 (SIRT3) AS A HOST FACTOR RESTRICTING HBV TRANSCRIPTION AND REPLICATION BY SCREENING SEVEN MEMBERS OF THE SIRTUIN FAMILY, WHICH IS THE CLASS III HISTONE DEACETYLASE. ECTOPIC SIRT3 EXPRESSION SIGNIFICANTLY REDUCED TOTAL HBV RNAS, 3.5-KB RNA, AS WELL AS REPLICATIVE INTERMEDIATE DNA IN HBV-INFECTED HEPG2-NA(+) /TAUROCHOLATE COTRANSPORTING POLYPEPTIDE CELLS AND PRIMARY HUMAN HEPATOCYTES. IN CONTRAST, GENE SILENCING OF SIRT3 PROMOTED HBV TRANSCRIPTION AND REPLICATION. A MECHANISTIC STUDY FOUND THAT NUCLEAR SIRT3 WAS RECRUITED TO THE HBV CCCDNA, WHERE IT DEACETYLATED HISTONE 3 LYSINE 9. IMPORTANTLY, OCCUPANCY OF SIRT3 ON CCCDNA COULD INCREASE THE RECRUITMENT OF HISTONE METHYLTRANSFERASE SUPPRESSOR OF VARIEGATION 3-9 HOMOLOG 1 TO CCCDNA AND DECREASE RECRUITMENT OF SET DOMAIN CONTAINING 1A, LEADING TO A MARKED INCREASE OF TRIMETHYL-HISTONE H3 (LYS9) AND A DECREASE OF TRIMETHYL-HISTONE H3 (LYS4) ON CCCDNA. MOREOVER, SIRT3-MEDIATED HBV CCCDNA TRANSCRIPTIONAL REPRESSION INVOLVED DECREASED BINDING OF HOST RNA POLYMERASE II AND TRANSCRIPTION FACTOR YIN YANG 1 TO CCCDNA. FINALLY, HEPATITIS B VIRAL X PROTEIN COULD RELIEVE SIRT3-MEDIATED CCCDNA TRANSCRIPTIONAL REPRESSION BY INHIBITING BOTH SIRT3 EXPRESSION AND ITS RECRUITMENT TO CCCDNA. CONCLUSION: SIRT3 IS A HOST FACTOR EPIGENETICALLY RESTRICTING HBV CCCDNA TRANSCRIPTION BY ACTING COOPERATIVELY WITH HISTONE METHYLTRANSFERASE; THESE DATA PROVIDE A RATIONALE FOR THE USE OF SIRT3 ACTIVATORS IN THE PREVENTION OR TREATMENT OF HBV INFECTION. (HEPATOLOGY 2018). 2018 19 1627 36 DNMT1 MODULATION IN CHRONIC HEPATITIS B PATIENTS AND HYPOTHETIC INFLUENCE ON MITOCHONDRIAL DNA METHYLATION STATUS DURING LONG-TERM NUCLEO(T)SIDE ANALOGS THERAPY. INHIBITION OF VIRAL REPLICATION IS THE MOST IMPORTANT GOAL IN PATIENTS WITH HEPATITIS B VIRUS CHRONIC INFECTION (CHB). CURRENTLY, FIVE ORAL NUCLEO(T)SIDE ANALOGS (NAS), INCLUDING LAMIVUDINE, ADEFOVIR, TELBIVUDINE, ENTECAVIR, AND TENOFOVIR, HAVE BEEN APPROVED FOR TREATMENT. THE WIDESPREAD USE OF NAS HAS ALSO BEEN LINKED WITH A PROGRESSIVE GROWTH OF UNLIKELY ANOMALY ATTRIBUTABLE TO MITOCHONDRIAL DYSFUNCTIONS, NOT PREVIOUSLY RECOGNIZED. HERE, WE EXPLORE THE HYPOTHESIS THAT NAS MAY CAUSE PERSISTENT EPIGENETIC CHANGES DURING PROLONGED NAS THERAPY IN CHB PATIENTS. WE OBTAINED PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMC) FROM WHOLE BLOOD SAMPLES OF CONSECUTIVE PATIENTS WITH CHRONIC HBV INFECTION, 18 RECEIVING NAS AND 20 UNTREATED PATIENTS. ALL PATIENTS WERE CAUCASIAN AND ITALIANS. EPIGENETIC ANALYSIS WAS PERFORMED BY BISULPHITE SEQUENCING PCR TO SEARCH THE EXISTENCE OF METHYLATED CYTOSINE RESIDUES IN THE LIGHT (L)-STRANDS OF MITOCHONDRIAL DNA CONTROL REGION (D-LOOP). GENE EXPRESSION ANALYSIS OF DNA METHYLTRANSFERASES 1 WAS PERFORMED BY A QUANTITATIVE RELATIVE REAL-TIME POLYMERASE CHAIN REACTION (PCR). DNMT1 EXPRESSION WAS SIGNIFICANTLY (P < 000001) HIGHER IN NA TREATED PATIENTS (4.09, IQR 3.52-5.15) WHEN COMPARED WITH HBV NAIVES (0.61, IQR 0.34-0.82). BESIDES, DNMT1 EXPRESSION WAS SIGNIFICANTLY CORRELATED WITH NA THERAPY DURATION (SPEARMAN RHO = 0.67; P < 0.05). FURTHERMORE, NA THERAPY DURATION WAS THE ONLY SIGNIFICANT PREDICTOR OF DNMT1 EXPRESSION AT MULTIVARIATE ANALYSIS (BETA = 0.95, P < 0.0000001). BISULPHITE PCR SEQUENCING SHOWED THAT METHYLATION OF CYTOSINE RESIDUES OCCURRED IN A HIGHER PERCENTAGE IN PATIENTS TREATED WITH NAS IN COMPARISON WITH UNTREATED PATIENTS AND HEALTHY CONTROLS. OUR DATA SHOWED A DNMT1 OVEREXPRESSION SIGNIFICANTLY CORRELATED TO NA THERAPY DURATION AND AN HIGHER REGIONAL MTDNA HYPERMETHYLATION. THIS MIGHT SUGGEST AN EPIGENETIC ALTERATION THAT COULD BE INVOLVED IN ONE OF THE POSSIBLE MECHANISMS OF MITOCHONDRIAL GENE REGULATION DURING NAS THERAPY. 2017 20 5226 35 PRMT5 RESTRICTS HEPATITIS B VIRUS REPLICATION THROUGH EPIGENETIC REPRESSION OF COVALENTLY CLOSED CIRCULAR DNA TRANSCRIPTION AND INTERFERENCE WITH PREGENOMIC RNA ENCAPSIDATION. CHRONIC HEPATITIS B VIRUS (HBV) INFECTION REMAINS A MAJOR HEALTH PROBLEM WORLDWIDE. THE COVALENTLY CLOSED CIRCULAR DNA (CCCDNA) MINICHROMOSOME, WHICH SERVES AS THE TEMPLATE FOR THE TRANSCRIPTION OF VIRAL RNAS, PLAYS A KEY ROLE IN VIRAL PERSISTENCE. WHILE ACCUMULATING EVIDENCE SUGGESTS THAT CCCDNA TRANSCRIPTION IS REGULATED BY EPIGENETIC MACHINERY, PARTICULARLY THE ACETYLATION OF CCCDNA-BOUND HISTONE 3 (H3) AND H4, THE POTENTIAL CONTRIBUTIONS OF HISTONE METHYLATION AND RELATED HOST FACTORS REMAIN OBSCURE. HERE, BY SCREENING A SERIES OF METHYLTRANSFERASES AND DEMETHYLASES, WE IDENTIFIED PROTEIN ARGININE METHYLTRANSFERASE 5 (PRMT5) AS AN EFFECTIVE RESTRICTOR OF HBV TRANSCRIPTION AND REPLICATION. IN CELL CULTURE-BASED MODELS FOR HBV INFECTION AND IN LIVER TISSUES OF PATIENTS WITH CHRONIC HBV INFECTION, WE FOUND THAT SYMMETRIC DIMETHYLATION OF ARGININE 3 ON H4 ON CCCDNA WAS A REPRESSIVE MARKER OF CCCDNA TRANSCRIPTION AND WAS REGULATED BY PRMT5 DEPENDING ON ITS METHYLTRANSFERASE DOMAIN. MOREOVER, PRMT5-TRIGGERED SYMMETRIC DIMETHYLATION OF ARGININE 3 ON H4 ON THE CCCDNA MINICHROMOSOME INVOLVED AN INTERACTION WITH THE HBV CORE PROTEIN AND THE BRG1-BASED HUMAN SWI/SNF CHROMATIN REMODELER, WHICH RESULTED IN DOWN-REGULATION OF THE BINDING OF RNA POLYMERASE II TO CCCDNA. IN ADDITION TO THE INHIBITORY EFFECT ON CCCDNA TRANSCRIPTION, PRMT5 INHIBITED HBV CORE PARTICLE DNA PRODUCTION INDEPENDENTLY OF ITS METHYLTRANSFERASE ACTIVITY. FURTHER STUDY REVEALED THAT PRMT5 INTERFERED WITH PREGENOMIC RNA ENCAPSIDATION BY PREVENTING ITS INTERACTION WITH VIRAL POLYMERASE PROTEIN THROUGH BINDING TO THE REVERSE TRANSCRIPTASE-RIBONUCLEASE H REGION OF POLYMERASE, WHICH IS CRUCIAL FOR THE POLYMERASE-PREGENOMIC RNA INTERACTION. CONCLUSION: PRMT5 RESTRICTS HBV REPLICATION THROUGH A TWO-PART MECHANISM INCLUDING EPIGENETIC SUPPRESSION OF CCCDNA TRANSCRIPTION AND INTERFERENCE WITH PREGENOMIC RNA ENCAPSIDATION; THESE FINDINGS IMPROVE THE UNDERSTANDING OF EPIGENETIC REGULATION OF HBV TRANSCRIPTION AND HOST-HBV INTERACTION, THUS PROVIDING NEW INSIGHTS INTO TARGETED THERAPEUTIC INTERVENTION. (HEPATOLOGY 2017;66:398-415). 2017