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 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 3 1428 36 DIFFERENTIAL EXPRESSION OF LONG NONCODING RNA IN HEPATOCELLULAR CARCINOMA ON TOP OF CHRONIC HCV AND HBV INFECTIONS. AIM OF THE STUDY: THE TASK OF LONG NONCODING RNAS (LNCRNAS) AS A PROSPECTIVE GOAL FOR HEPATOCELLULAR CARCINOMA (HCC) IS A CANDIDATE FOR RESEARCH. SEVERAL LNCRNAS ARE INVOLVED IN SIGNAL TRANSDUCTION, DIRECTING GENE EXPRESSION AND EPIGENETIC ALTERATION IN NORMAL AND CANCER CELLS. DYSREGULATION OF DIVERSE LNCRNAS HAS BEEN INVOLVED IN THE PATHOGENESIS AND PROGRESSION OF DIFFERENT CANCERS INCLUDING HCC. WE AIMED TO INVESTIGATE THE DIFFERENTIAL EXPRESSION OF LNCRNAS (AHIF, HPVT1, ANRIL) IN HCC ON TOP OF CHRONIC HEPATITIS C VIRUS (HCV) AND HEPATITIS B VIRUS (HBV) INFECTIONS. MATERIAL AND METHODS: 182 PARTICIPANTS WERE INCLUDED: 85 PATIENTS WITH HCC IN ADDITION TO 50 PATIENTS WITH CIRRHOSIS ON TOP OF CHRONIC HCV OR HBV, AND 47 HEALTHY SUBJECTS AS CONTROLS. HCC WAS DIAGNOSED BY TRIPHASIC COMPUTED TOMOGRAPHY (CT). DETECTION OF ALPHA-FETOPROTEIN (AFP) AND SEROLOGICAL MARKERS OF HCVAB AND HBSAG BY ENZYME-LINKED FLUORESCENT IMMUNOASSAY (ELFA) AND QUANTITATION OF LNCRNAS BY REAL TIME PCR WERE APPLIED. RESULTS: UPREGULATION OF ANRIL AND HPVT1 AND DOWNREGULATION OF AHIF WERE OBSERVED IN PATIENTS WITH HCC ON TOP OF HCV AND HBV VS. CONTROLS. CIRCULATING AHIF COULD BE OF MAJOR DIAGNOSTIC IMPORTANCE TO DISCRIMINATE HCC ON TOP OF HCV FROM CIRRHOTIC PATIENTS WITH SENSITIVITY 86.67% AND SPECIFICITY 91.89% WHEREAS CIRCULATING HPVT1 HAD SENSITIVITY 85.0% AND SPECIFICITY 84.62%; MOREOVER ANRIL HAD AUC 0.902 AND COULD DISCRIMINATE HCC ON TOP OF HBV FROM CIRRHOTIC PATIENTS. CONCLUSIONS: THE DIFFERENTIAL EXPRESSION OF LNCRNAS (ANRIL, HPVT1 AND AHIF) MIGHT BE OF MAJOR WORTH IN PREDICTING THE OCCURRENCE OF HCC IN CIRRHOTIC PATIENTS RELATED TO CHRONIC VIRAL HEPATITIS AND COULD BE BENEFICIAL IN THE EARLY MANAGEMENT. 2021 4 5678 32 SHORT HAIRPIN RNA INDUCES METHYLATION OF HEPATITIS B VIRUS COVALENTLY CLOSED CIRCULAR DNA IN HUMAN HEPATOMA CELLS. SMALL INTERFERING RNAS NOT ONLY MODULATE GENE EXPRESSION AT A POST-TRANSCRIPTIONAL LEVEL, BUT ALSO INDUCE TRANSCRIPTIONAL GENE SILENCING BY RNA INTERFERENCE-MEDIATED HETEROCHROMATIN FORMATION AND RNA-DIRECTED DNA METHYLATION (RDDM). HOWEVER, ALTHOUGH ESTABLISHED IN PLANTS, THERE HAVE BEEN CONTROVERSIES WHETHER RDDM OPERATES IN MAMMALS. HEPATITIS B VIRUS (HBV) COVALENTLY CLOSED CIRCULAR DNA (CCCDNA) SERVES AS A TEMPLATE FOR VIRAL RNA TRANSCRIPTION, AND TRANSCRIPTIONAL ACTIVITY OF HBV CCCDNA IS REGULATED BY METHYLATION IN PATIENTS WITH CHRONIC HBV INFECTION. IN THIS STUDY, WE STABLY EXPRESSED SHORT HAIRPIN RNA (SHRNA) AGAINST HBV IN HUMAN HEPATOMA CELLS TO DETERMINE WHETHER SHRNA INDUCES METHYLATION OF HBV CCCDNA. HEPAD38 CELLS WHICH PERMIT REPLICATION OF HBV UNDER CONTROL OF TETRACYCLINE-RESPONSIVE PROMOTER WERE TRANSDUCED WITH LENTIVIRAL VECTORS WHICH ENCODE SH-1580, A SHRNA AGAINST THE HEPATITIS B VIRAL PROTEIN HBX. BISULFITE SEQUENCING PCR ANALYSIS REVEALED THAT SH-1580 INDUCED CPG METHYLATIONS AT A HIGHER RATE COMPARED TO CONTROL (31.3% VS. 12.8%, P<0.05). THE SH-1580-INDUCED CPG METHYLATION WAS LOCALIZED NEAR THE TARGET SEQUENCE OF SH-1580 IN MORE THAN A HALF OF THE CLONES. METHYLATION-INDUCED TRANSCRIPTIONAL SUPPRESSION WAS CONFIRMED BY IN VITRO TRANSCRIPTION ASSAY. THESE RESULTS CONFIRM THE FEASIBILITY OF RDDM OF HBV CCCDNA IN HUMAN CELLS. LENTIVIRAL VECTOR-MEDIATED TRANSFER OF SHRNA MAY BE USED AS A TOOL FOR NOVEL TRANSCRIPTIONAL MODULATION BY EPIGENETIC MODIFICATION OF HBV CCCDNA. 2013 5 6645 34 UP-REGULATION OF DBPA MRNA IN HEPATOCELLULAR CARCINOMA ASSOCIATED WITH METABOLIC SYNDROME. PURPOSE: METABOLIC SYNDROME (MS) IS A GROUP OF RECOGNIZED RISK FACTORS FOR THE DEVELOPMENT OF HEPATOCELLULAR CARCINOMA (HCC) IN PATIENTS WITH CHRONIC LIVER DISEASE. THE AIM OF THIS STUDY WAS TO ANALYZE THE CLINICOPATHOLOGICAL CHARACTERISTICS OF HCC PATIENTS WITH MS AND THE RISK FACTORS FOR RECURRENCE. ALSO, THE AIM WAS TO INVESTIGATE THE COLD SHOCK PROTEIN: DNA-BINDING PROTEIN A (DBPA) EXPRESSION IN HCC PATIENTS WITH MS. METHODS: A TOTAL OF 243 PATIENTS WHO UNDERWENT CURATIVE RESECTIONS FOR HCC WERE CLASSIFIED INTO TWO GROUPS. DBPA EXPRESSION WAS INVESTIGATED IN 66 HCC PATIENTS WITH MS AND IN 30 PATIENTS WITHOUT MS BY USING REAL-TIME RT-PCR. PROMOTER METHYLATION STATUS WAS EXAMINED BY USING MS-PCR. RESULTS: THE INCIDENCE OF METABOLIC FACTORS AFFECT THE HCC SIGNIFICANTLY HIGHER IN NON-B NON-C PATIENTS THAN IN HEPATITIS B VIRUS (HBV) OR HEPATITIS C VIRUS (HCV) PATIENTS (P < 0.001). UNIVARIATE ANALYSIS OF HCC PATIENTS WITH MS RECURRENCE REVEALED ASPARTATE AMINO TRANSFERASE (AST), MULTIPLE TUMORS, LIVER DAMAGE, HEPATIC VEIN INVASION, ADVANCED CANCER STAGES (P < 0.01), ALPHA-FETOPROTEIN (AFP) AND DIABETES MELLITUS TYPE II (P < 0.05) AS RISK FACTORS. MULTIVARIATE ANALYSIS, AST, MULTIPLE TUMORS, AND HEPATIC VEIN INVASION (P < 0.01) WERE IDENTIFIED AS INDEPENDENT FACTORS FOR THE RECURRENCE. DBPA MRNA WAS HIGHER IN PATIENTS WITH MS THAN IN THOSE WITHOUT MS (P = 0.016), AND IT WAS MOSTLY UPREGULATED IN NON-B NON-C HCC PATIENTS WITH MS THAN IN NON-B NON-C HCC PATIENTS WITHOUT HBV OR HCV. ESPECIALLY, IN HCC PATIENTS WITH DIABETES MELLITUS TYPE II, THE MRNA AND PROTEIN LEVELS WERE HIGHLY UPREGULATED. THE DBPA EXPRESSION WAS REGULATED BY PROMOTER METHYLATION STATUS (P < 0.05). CONCLUSIONS: THIS STUDY IDENTIFIES THAT DBPA MAY ACCELERATE THE HEPATOCARCINOGENESIS IN HCC PATIENTS WITH MS VIA INFLAMMATION-INDUCED AND OXIDATIVE STRESS PATHWAYS. THE DEMETHYLATION-RELATED EPIGENETIC ACTIVATION MAY BE ONE OF THE REGULATING FACTORS FOR HCC PATIENTS WITH MS. 2013 6 4771 36 NUCLEAR SENSOR INTERFERON-INDUCIBLE PROTEIN 16 INHIBITS THE FUNCTION OF HEPATITIS B VIRUS COVALENTLY CLOSED CIRCULAR DNA BY INTEGRATING INNATE IMMUNE ACTIVATION AND EPIGENETIC SUPPRESSION. BACKGROUND AND AIMS: NUCLEAR-LOCATED COVALENTLY CLOSED CIRCULAR DNA (CCCDNA) OF HEPATITIS B VIRUS (HBV) IS A DETERMINING FACTOR FOR HBV PERSISTENCE AND THE KEY OBSTACLE FOR A CURE OF CHRONIC HEPATITIS B. HOWEVER, IT REMAINS UNCLEAR WHETHER AND HOW THE HOST IMMUNE SYSTEM SENSES HBV CCCDNA AND ITS BIOLOGICAL CONSEQUENCES. APPROACH AND RESULTS: HERE, WE DEMONSTRATED THAT INTERFERON-INDUCIBLE PROTEIN 16 (IFI16) COULD SERVE AS A UNIQUE INNATE SENSOR TO RECOGNIZE AND BIND TO HBV CCCDNA IN HEPATIC NUCLEI, LEADING TO THE INHIBITION OF CCCDNA TRANSCRIPTION AND HBV REPLICATION. MECHANISTICALLY, OUR DATA SHOWED THAT IFI16 PROMOTED THE EPIGENETIC SUPPRESSION OF HBV CCCDNA BY TARGETING AN INTERFERON-STIMULATED RESPONSE ELEMENT (ISRE) PRESENT IN CCCDNA. IT IS OF INTEREST THAT THIS ISRE WAS ALSO REVEALED TO PLAY AN IMPORTANT ROLE IN IFI16-ACTIVATED TYPE I INTERFERON RESPONSES. FURTHERMORE, OUR DATA REVEALED THAT HBV COULD DOWN-REGULATE THE EXPRESSION LEVEL OF IFI16 IN HEPATOCYTES, AND THERE WAS A NEGATIVE CORRELATION BETWEEN IFI16 AND HBV TRANSCRIPTS IN LIVER BIOPSIES, SUGGESTING THE POSSIBLE ROLE OF IFI16 IN SUPPRESSING CCCDNA FUNCTION UNDER PHYSIOLOGICAL CONDITIONS. CONCLUSIONS: THE NUCLEAR SENSOR IFI16 SUPPRESSES CCCDNA FUNCTION BY INTEGRATING INNATE IMMUNE ACTIVATION AND EPIGENETIC REGULATION BY TARGETING THE ISRE OF CCCDNA, AND IFI16 MAY PRESENT AS A THERAPEUTIC TARGET AGAINST HBV INFECTION. 2020 7 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 8 3307 32 HIGH-RESOLUTION GENOMIC PROFILING OF LIVER CANCER LINKS ETIOLOGY WITH MUTATION AND EPIGENETIC SIGNATURES. BACKGROUND & AIMS: HEPATOCELLULAR CARCINOMA (HCC) IS A MODEL OF A DIVERSE SPECTRUM OF CANCERS BECAUSE IT IS INDUCED BY WELL-KNOWN ETIOLOGIES, MAINLY HEPATITIS C VIRUS (HCV) AND HEPATITIS B VIRUS. HERE, WE AIMED TO IDENTIFY HCV-SPECIFIC MUTATIONAL SIGNATURES AND EXPLORED THE LINK BETWEEN THE HCV-RELATED REGIONAL VARIATION IN MUTATIONS RATES AND HCV-INDUCED ALTERATIONS IN GENOME-WIDE CHROMATIN ORGANIZATION. METHODS: TO IDENTIFY AN HCV-SPECIFIC MUTATIONAL SIGNATURE IN HCC, WE PERFORMED HIGH-RESOLUTION TARGETED SEQUENCING TO DETECT PASSENGER MUTATIONS ON 64 HCC SAMPLES FROM 3 ETIOLOGY GROUPS: HEPATITIS B VIRUS, HCV, OR OTHER. TO EXPLORE THE LINK BETWEEN THE GENOMIC SIGNATURE AND GENOME-WIDE CHROMATIN ORGANIZATION WE PERFORMED CHROMATIN IMMUNOPRECIPITATION SEQUENCING FOR THE TRANSCRIPTIONALLY PERMISSIVE H3K4ME3, H3K9AC, AND SUPPRESSIVE H3K9ME3 MODIFICATIONS AFTER HCV INFECTION. RESULTS: REGIONAL VARIATION IN MUTATION RATE ANALYSIS SHOWED SIGNIFICANT ETIOLOGY-DEPENDENT REGIONAL MUTATION RATES IN 12 GENES: LRP2, KRT84, TMEM132B, DOCK2, DMD, INADL, JAK2, DNAH6, MTMR9, ATM, SLX4, AND ARSD. WE FOUND AN ENRICHMENT OF C->T TRANSVERSION MUTATIONS IN THE HCV-ASSOCIATED HCC CASES. FURTHERMORE, THESE CASES SHOWED REGIONAL VARIATION IN MUTATION RATES ASSOCIATED WITH GENOMIC INTERVALS IN WHICH HCV INFECTION DICTATED EPIGENETIC ALTERATIONS. THIS SIGNATURE MAY BE RELATED TO THE HCV-INDUCED DECREASED EXPRESSION OF GENES ENCODING KEY ENZYMES IN THE BASE EXCISION REPAIR PATHWAY. CONCLUSIONS: WE IDENTIFIED NOVEL DISTINCT HCV ETIOLOGY-DEPENDENT MUTATION SIGNATURES IN HCC ASSOCIATED WITH HCV-INDUCED ALTERATIONS IN HISTONE MODIFICATION. THIS STUDY PRESENTS A LINK BETWEEN CANCER-CAUSING MUTAGENESIS AND THE INCREASED PREDISPOSITION TO LIVER CANCER IN CHRONIC HCV-INFECTED INDIVIDUALS, AND UNVEILS NOVEL ETIOLOGY-SPECIFIC MECHANISMS LEADING TO HCC AND CANCER IN GENERAL. 2023 9 155 29 ABERRANT METHYLATION OF POLO-LIKE KINASE CPG ISLANDS IN PLK4 HETEROZYGOUS MICE. BACKGROUND: HEPATOCELLULAR CARCINOMA (HCC), ONE OF THE MOST COMMON CANCERS WORLD-WIDE OCCURS TWICE AS OFTEN IN MEN COMPARED TO WOMEN. PREDISPOSING CONDITIONS SUCH AS ALCOHOLISM, CHRONIC VIRAL HEPATITIS, AFLATOXIN B1 INGESTION, AND CIRRHOSIS ALL CONTRIBUTE TO THE DEVELOPMENT OF HCC. METHODS: WE USED A COMBINATION OF METHYLATION SPECIFIC PCR AND BISULFITE SEQUENCING, QREAL-TIME PCR (QPCR), AND WESTERN BLOT ANALYSIS TO EXAMINE EPIGENETIC CHANGES FOR THE POLO-LIKE KINASES (PLKS) DURING THE DEVELOPMENT OF HEPATOCELLULAR CARCINOMA (HCC) IN PLK4 HETEROZYGOUS MICE AND MURINE EMBRYONIC FIBROBLASTS (MEFS). RESULTS: HERE WE REPORT THAT THE PROMOTER METHYLATION OF PLK4 CPG ISLANDS INCREASES WITH AGE, WAS MORE PREVALENT IN MALES AND THAT PLK4 EPIGENETIC MODIFICATION AND SUBSEQUENT DOWNREGULATION OF EXPRESSION WAS ASSOCIATED WITH THE DEVELOPMENT OF HCC IN PLK4 MUTANT MICE. INTERESTINGLY, THE OPPOSITE OCCURS WITH ANOTHER PLK FAMILY MEMBER, PLK1 WHICH WAS TYPICALLY HYPERMETHYLATED IN NORMAL LIVER TISSUE BUT BECAME HYPOMETHYLATED AND UPREGULATED IN LIVER TUMOURS. FURTHERMORE, UPON ALCOHOL EXPOSURE MURINE EMBRYONIC FIBROBLASTS EXHIBITED INCREASED PLK4 HYPERMETHYLATION AND DOWNREGULATION ALONG WITH INCREASED CENTROSOME NUMBERS AND MULTINUCLEATION. CONCLUSIONS: THESE RESULTS SUGGEST THAT ABERRANT PLK METHYLATION IS CORRELATED WITH THE DEVELOPMENT OF HCC IN MICE. 2011 10 412 34 ANALYSIS OF LONG NON-CODING RNA (LNCRNA) EXPRESSION IN HEPATITIS B PATIENTS. LONG NON-CODING RNAS (LNCRNAS) HAVE BEEN IMPLICATED IN NUMEROUS BIOLOGICAL PROCESSES, INCLUDING EPIGENETIC REGULATION, CELL-CYCLE CONTROL, AND TRANSCRIPTIONAL/TRANSLATIONAL REGULATION OF GENE EXPRESSION. DIFFERENTIAL EXPRESSION OF LNCRNAS AND DISRUPTION OF THE REGULATORY PROCESSES ARE RECOGNIZED AS CRITICAL STEPS IN CANCER DEVELOPMENT. THE ROLE OF LNCRNAS IN HEPATITIS B VIRUS (HBV) INFECTION IS NOT WELL UNDERSTOOD. HERE WE ANALYZED THE EXPRESSION OF 135 LNCRNAS IN PLASMA SAMPLES OF 82 HBV PATIENTS (CLASSIFIED AS CHRONIC PATIENTS, INACTIVE CARRIERS, OR RESOLVED PATIENTS) AT DIAGNOSIS AND AT 12 MONTHS OF TREATMENT IN RELATION TO CONTROL GROUP (81 HEALTHY VOLUNTEERS). WE ALSO INVESTIGATED THE EFFECT OF SMALL INTERFERING RNA (SIRNA)-MEDIATED SILENCING OF LINCRNA-SFMBT2 ON HBV-POSITIVE HUMAN LIVER CANCER CELL LINE. LNCRNA EXPRESSION WAS ANALYZED BY QUANTITATIVE REVERSE TRANSCRIPTION-POLYMERASE CHAIN REACTION (QRT-PCR). CHEMICALLY SYNTHESIZED SIRNAS WERE TRANSFECTED INTO THE CELL LINES USING LIPOFECTAMINE 2000 REAGENT (THERMO FISHER SCIENTIFIC). HBV DNA AND HBSAG AND HBEAG WERE DETECTED IN TRANSFECTED CULTURES BY REAL-TIME PCR AND ELISA, RESPECTIVELY, USING COMMERCIAL KITS. WE OBSERVED CHANGES IN LNCRNA EXPRESSION IN ALL THREE HBV GROUPS, COMPARED TO CONTROL GROUP. MOST NOTABLY, THE EXPRESSION OF ANTI-NOS2A, LINCRNA-SFMBT2, AND ZFHX2AS WAS SIGNIFICANTLY INCREASED AND EXPRESSION OF Y5 LNCRNA WAS DECREASED IN CHRONIC HBV PATIENTS. A DECREASED Y5 EXPRESSION AND INCREASED LINCRNA-SFMBT2 EXPRESSION WERE OBSERVED IN INACTIVE HBSAG CARRIERS. THE EXPRESSION OF HOTTIP, MEG9, AND PCAT-32 WAS INCREASED IN RESOLVED HBV PATIENTS, AND NO SIGNIFICANT CHANGE IN THE EXPRESSION OF Y5 WAS OBSERVED, COMPARED TO CONTROL GROUP. SIRNA-MEDIATED INHIBITION OF LINCRNA-SFMBT2 DECREASED THE LEVEL OF HBV DNA IN HUMAN LIVER CANCER CELLS. FURTHER RESEARCH IS NEEDED TO CONFIRM THE PROGNOSTIC AS WELL AS THERAPEUTIC ROLE OF THESE LNCRNAS IN HBV PATIENTS. 2018 11 4225 26 METHYLATION DEGREE OF METALLOPROTEINASE INHIBITOR RECK GENE: LINKS TO RECK PROTEIN LEVEL AND HEPATOCELLULAR CARCINOMA IN CHRONIC HCV INFECTION PATIENTS. THE RECK GENE, A TUMOR SUPPRESSOR GENE, INHIBITS ANGIOGENESIS, INVASION, AND TUMOR METASTASIS. EPIGENETIC REGULATION OF THE RECK GENE CONSTITUTES A POTENT APPROACH TO THE MOLECULAR BASIS OF LIVER MALIGNANCY. THIS STUDY AIMS TO EVALUATE THE PROMOTER METHYLATION STATUS OF THE RECK GENE AND ITS SERUM LEVEL IN PATIENTS WITH HEPATITIS C VIRUS (HCV)-RELATED HEPATOCELLULAR CARCINOMA (HCC) AND THE POTENTIAL ASSOCIATION OF RECK GENE METHYLATION WITH CLINICAL CRITERIA OF HCC. ONE HUNDRED AND FIFTY-FIVE SUBJECTS WERE INCLUDED (HEALTHY CONTROL [55], CHRONIC HCV PATIENTS [55], HCV-RELATED HCC PATIENTS [45]). THE METHYLATION STATUS OF THE RECK GENE PROMOTER AND SERUM RECK LEVEL WERE INVESTIGATED BY METHYLATION-SPECIFIC PCR AND ENZYME-LINKED IMMUNOSORBENT ASSAY TECHNIQUES, RESPECTIVELY. RECK GENE PROMOTER HYPERMETHYLATION WAS RECORDED IN 46.7% OF HCC PATIENTS, AND 10.9% OF HCV PATIENTS, BUT NOT IN CONTROL SUBJECTS (0%). IT WAS RELATED TO RECK PROTEIN LEVEL, VARICES, EDEMA, ASCITES, LYMPH NODE METASTASIS, VASCULAR INVASION, AND THE LARGEST DIAMETER OF FOCAL LESIONS. MEANWHILE, IT WAS NOT ASSOCIATED WITH FOCAL LESION NUMBER NOR DISTANT METASTASIS OF HCC. IN CONCLUSION, RECK GENE PROMOTER HYPERMETHYLATION IS LINKED TO HCV GENOTYPE-4-RELATED HCC. MOREOVER, DIFFERENT DEGREES OF RECK GENE PROMOTER METHYLATION ARE ASSOCIATED WITH SERUM RECK LEVEL, LYMPH NODE METASTASIS, AND VASCULAR INVASION, WHICH COULD PROVE ITS PATHOGENIC ROLE IN HEPATOCARCINOGENESIS IN CHRONIC HCV-INFECTED PATIENTS. 2021 12 3252 41 HEPATITIS B VIRUS SUPPRESSES COMPLEMENT C9 SYNTHESIS BY LIMITING THE AVAILABILITY OF TRANSCRIPTION FACTOR USF-1 AND INHIBITS FORMATION OF MEMBRANE ATTACK COMPLEX: IMPLICATIONS IN DISEASE PATHOGENESIS. BACKGROUND: THE COMPLEMENT SYSTEM FUNCTIONS PRIMARILY AS A FIRST-LINE HOST DEFENSE AGAINST INVADING MICROBES, INCLUDING VIRUSES. HOWEVER, THE INTERACTION OF HEPATITIS B VIRUS (HBV) WITH THE COMPLEMENT-COMPONENTS DURING CHRONIC HBV INFECTION REMAINS LARGELY UNKNOWN. WE INVESTIGATED THE MECHANISM BY WHICH HBV INHIBITS THE FORMATION OF CYTOLYTIC COMPLEMENT MEMBRANE-ATTACK COMPLEX (MAC) AND STUDIED ITS IMPACT ON MAC-MEDIATED MICROBICIDAL ACTIVITY AND DISEASE PATHOGENESIS. METHODS: BLOOD/LIVER TISSUES WERE COLLECTED FROM CHRONICALLY HBV-INFECTED PATIENTS AND CONTROLS. HEPG2(HNTCP) CELLS WERE INFECTED WITH HBV PARTICLES AND HUH7 CELLS WERE TRANSFECTED WITH FULL-LENGTH LINEAR HBV-MONOMER OR PLASMIDS CONTAINING DIFFERENT HBV-ORFS AND EXPRESSION OF COMPLEMENT COMPONENTS OR OTHER HOST GENES WERE EVALUATED. ADDITIONALLY, ELISA, REAL-TIME PCR, WESTERN BLOT, BIOINFORMATICS ANALYSIS, GENE OVEREXPRESSION/KNOCK-DOWN, MUTAGENESIS, CHROMATIN IMMUNOPRECIPITATION, EPIGENETIC STUDIES, IMMUNOFLUORESCENCE, AND QUANTIFICATION OF SERUM HBV-DNA, BACTERIAL-DNA AND ENDOTOXIN WERE PERFORMED. RESULTS: AMONG THE MAC COMPONENTS (C5B-C9), SIGNIFICANT REDUCTION WAS NOTED IN THE EXPRESSION OF C9, THE MAJOR CONSTITUENT OF MAC, IN HBV-INFECTED HEPG2(HNTCP) CELLS AND IN HUH7 CELLS TRANSFECTED WITH FULL-LENGTH HBV AS WELL AS HBX. C9 LEVEL WAS ALSO MARKED LOW IN SERA/LIVER OF CHRONIC HEPATITIS B (CHB) AND IMMUNE-TOLERANT (IT) PATIENTS THAN INACTIVE CARRIERS AND HEALTHY CONTROLS. HBX STRONGLY REPRESSED C9-PROMOTER ACTIVITY IN HUH7 CELLS BUT CPG-ISLAND WAS NOT DETECTED IN C9-PROMOTER. WE IDENTIFIED USF-1 AS THE KEY TRANSCRIPTION FACTOR THAT DRIVES C9 EXPRESSION AND DEMONSTRATED THAT HBX-INDUCED HYPERMETHYLATION OF USF-1-PROMOTER IS THE LEADING CAUSE OF USF-1 DOWNREGULATION THAT IN TURN DIMINISHED C9 TRANSCRIPTION. REDUCED MAC FORMATION AND IMPAIRED LYSIS OF HBV-TRANSFECTED HUH7 AND BACTERIAL CELLS WERE OBSERVED FOLLOWING INCUBATION OF THESE CELLS WITH C9-DEFICIENT CHB SERA BUT WAS REVERSED UPON C9 SUPPLEMENTATION. SIGNIFICANT INVERSE CORRELATION WAS NOTED BETWEEN C9 CONCENTRATION AND HBV-DNA, BACTERIAL-DNA AND ENDOTOXIN CONTENT IN HBV-INFECTED PATIENTS. ONE-YEAR TENOFOVIR THERAPY RESULTED IN IMPROVEMENT IN C9 LEVEL AND DECLINE IN VIRAL/BACTERIAL/ENDOTOXIN LOAD IN CHB PATIENTS. CONCLUSION: COLLECTIVELY, HBX SUPPRESSED C9 TRANSCRIPTION BY RESTRICTING THE AVAILABILITY OF USF-1 THROUGH HYPERMETHYLATION OF USF-1-PROMOTER AND CONSEQUENTLY HINDER THE FORMATION AND LYTIC FUNCTIONS OF MAC. EARLY THERAPY IS NEEDED FOR BOTH CHB AND IT TO NORMALIZE THE ABERRANT COMPLEMENT PROFILE AND CONTAIN VIRAL AND BACTERIAL INFECTION AND LIMIT DISEASE PROGRESSION. 2022 13 5349 31 RASSF1A AND DOK1 PROMOTER METHYLATION LEVELS IN HEPATOCELLULAR CARCINOMA, CIRRHOTIC AND NON-CIRRHOTIC LIVER, AND CORRELATION WITH LIVER CANCER IN BRAZILIAN PATIENTS. HEPATOCELLULAR CARCINOMA (HCC) IS THE SECOND MOST COMMON CAUSE OF CANCER MORTALITY WORLDWIDE. MOST CASES OF HCC ARE ASSOCIATED WITH CIRRHOSIS RELATED TO CHRONIC HEPATITIS B VIRUS OR HEPATITIS C VIRUS INFECTIONS. HYPERMETHYLATION OF PROMOTER REGIONS IS THE MAIN EPIGENETIC MECHANISM OF GENE SILENCING AND HAS BEEN INVOLVED IN HCC DEVELOPMENT. THE AIM OF THIS STUDY WAS TO DETERMINE WHETHER ABERRANT METHYLATION OF RASSF1A AND DOK1 GENE PROMOTERS IS ASSOCIATED WITH THE PROGRESSION OF LIVER DISEASE IN BRAZILIAN PATIENTS. METHYLATION LEVELS WERE MEASURED BY PYROSEQUENCING IN 41 (20 HCC, 9 CIRRHOTIC, AND 12 NON-CIRRHOTIC) LIVER TISSUE SAMPLES. MEAN RATES OF METHYLATION IN RASSF1A AND DOK1 WERE 16.2% AND 12.0% IN NON-CIRRHOTIC, 26.1% AND 19.6% IN CIRRHOTIC, AND 59.1% AND 56.0% IN HCC TISSUES, RESPECTIVELY, SHOWING A GRADUAL INCREASE ACCORDING TO THE PROGRESSION OF THE DISEASE, WITH SIGNIFICANTLY HIGHER LEVELS IN TUMOR TISSUES. IN ADDITION, HYPERMETHYLATION OF RASSF1A AND DOK1 WAS FOUND IN THE VAST MAJORITY (88%) OF THE HCC CASES. INTERESTINGLY, DOK1 METHYLATION LEVELS IN HCC SAMPLES WERE SIGNIFICANTLY HIGHER IN THE GROUP OF YOUNGER (<40 YEARS) PATIENTS, AND HIGHER IN MODERATELY DIFFERENTIATED THAN IN POORLY DIFFERENTIATED TUMORS (P < 0.05). OUR RESULTS REINFORCE THE HYPOTHESIS THAT HYPERMETHYLATION OF RASSF1A AND DOK1 CONTRIBUTES TO HEPATOCARCINOGENESIS AND IS ASSOCIATED TO CLINICOPATHOLOGICAL CHARACTERISTICS. RASSF1A AND DOK1 PROMOTER HYPERMETHYLATION MAY BE A VALUABLE BIOMARKER FOR EARLY DIAGNOSIS OF HCC AND A POTENTIAL MOLECULAR TARGET FOR EPIGENETIC-BASED THERAPY. 2016 14 3476 37 IDENTIFICATION OF A TRANSMEMBRANE PROTEIN INVOLVED IN SHEAR STRESS SIGNALING AND HEPATOCARCINOGENESIS AFTER A SUSTAINED VIROLOGICAL RESPONSE TO HEPATITIS C VIRUS. BACKGROUND & AIMS: THE RISK OF HEPATOCELLULAR CARCINOMA (HCC) REMAINS AFTER ACHIEVING A SUSTAINED VIROLOGICAL RESPONSE (SVR) IN PATIENTS WITH CHRONIC HEPATITIS C (CHC). EPIGENETIC ABNORMALITIES MIGHT BE KEY REGULATORS IN THE DEVELOPMENT OF HCC. THIS STUDY AIMED TO IDENTIFY THE GENES INVOLVED IN HEPATOCARCINOGENESIS AFTER AN SVR. METHODS: DNA METHYLATION IN LIVER TISSUE WAS COMPARED BETWEEN 21 CHC PATIENTS WITHOUT HCC AND 28 CHC PATIENTS WITH HCC, ALL OF WHOM HAD ACHIEVED AN SVR. ADDITIONAL COMPARISONS WITH 23 CHC PATIENTS BEFORE TREATMENT AND 10 NORMAL LIVERS WERE PERFORMED. THE CHARACTERISTICS OF A NEWLY IDENTIFIED GENE WERE EXPLORED IN VITRO AND IN VIVO. RESULTS: WE FOUND THAT THE TRANSMEMBRANE PROTEIN NO. 164 (TMEM164) GENE WAS DEMETHYLATED BY HEPATITIS C VIRUS INFECTION AND HCC DEVELOPMENT AFTER ACHIEVING AN SVR. TMEM164 WAS EXPRESSED MAINLY IN ENDOTHELIAL CELLS, ALPHA SMOOTH MUSCLE ACTIN-POSITIVE CELLS, AND SOME CAPILLARIZED LIVER SINUSOIDAL ENDOTHELIAL CELLS. TMEM164 EXPRESSION WAS SIGNIFICANTLY CORRELATED WITH LIVER FIBROSIS AND RELAPSE-FREE SURVIVAL IN HCC PATIENTS. TMEM164 WAS INDUCED BY SHEAR STRESS, INTERACTED WITH GRP78/BIP, ACCELERATED ATF6 (ACTIVATING TRANSCRIPTION FACTOR 6)-MEDIATED ENDOPLASMIC RETICULUM (ER) STRESS SIGNALING, AND ACTIVATED INTERLEUKIN-6/STAT3 (SIGNAL TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION 3) SIGNALING IN THE TMNK1 LIVER ENDOTHELIAL CELL LINE. THEREFORE, WE TERMED TMEM164 "SHEAR STRESS-INDUCED TRANSMEMBRANE PROTEIN ASSOCIATED WITH ER STRESS SIGNALING" (SHERMER). SHERMER KNOCKOUT MICE WERE PROTECTED AGAINST CCL4-INDUCED LIVER FIBROSIS. SHERMER OVEREXPRESSION IN TMNK1 CELLS ACCELERATED HCC GROWTH IN A XENOGRAFT MODEL. CONCLUSIONS: WE IDENTIFIED A NEW TRANSMEMBRANE PROTEIN, SHERMER, IN CHC PATIENTS WITH HCC AFTER ACHIEVING AN SVR. SHERMER WAS INDUCED BY SHEAR STRESS AND ACCELERATED ATF6-MEDIATED ER STRESS SIGNALING IN ENDOTHELIAL CELLS. THUS, SHERMER IS A NOVEL ENDOTHELIAL MARKER ASSOCIATED WITH LIVER FIBROSIS, HEPATOCARCINOGENESIS, AND PROGRESSION OF HCC. 2023 15 3728 28 INHIBITION OF REPLICATION OF HEPATITIS B VIRUS USING TRANSCRIPTIONAL REPRESSORS THAT TARGET THE VIRAL DNA. BACKGROUND: CHRONIC INFECTION WITH HEPATITIS B VIRUS (HBV) IS A SERIOUS GLOBAL HEALTH PROBLEM. PERSISTENCE OF THE VIRUS OCCURS AS A RESULT OF STABILITY OF THE REPLICATION INTERMEDIATE COMPRISING COVALENTLY CLOSED CIRCULAR DNA (CCCDNA). DEVELOPMENT OF DRUGS THAT ARE CAPABLE OF DISABLING THIS CCCDNA IS VITAL. METHODS: TO INVESTIGATE AN EPIGENETIC APPROACH TO INACTIVATING VIRAL DNA, WE ENGINEERED TRANSCRIPTIONAL REPRESSORS THAT COMPRISE AN HBV DNA-BINDING DOMAIN OF TRANSCRIPTION ACTIVATOR LIKE EFFECTORS (TALES) AND A FUSED KRUPPEL ASSOCIATED BOX (KRAB). THESE REPRESSOR TALES (RTALES) TARGETED THE VIRAL SURFACE OPEN READING FRAME AND WERE PLACED UNDER TRANSCRIPTION CONTROL OF CONSTITUTIVELY ACTIVE OR LIVER-SPECIFIC PROMOTERS. RESULTS: EVALUATION IN CULTURED CELLS AND FOLLOWING HYDRODYNAMIC INJECTION OF MICE REVEALED THAT THE RTALES SIGNIFICANTLY INHIBITED PRODUCTION OF MARKERS OF HBV REPLICATION WITHOUT EVIDENCE OF HEPATOTOXICITY. INCREASED METHYLATION OF HBV DNA AT CPG ISLAND II SHOWED THAT THE RTALES CAUSED INTENDED EPIGENETIC MODIFICATION. CONCLUSIONS: EPIGENETIC MODIFICATION OF HBV DNA IS A NEW AND EFFECTIVE MEANS OF INACTIVATING THE VIRUS IN VIVO. THE APPROACH HAS THERAPEUTIC POTENTIAL AND AVOIDS POTENTIALLY PROBLEMATIC UNINTENDED MUTAGENESIS OF GENE EDITING. 2019 16 758 40 CAS9-TARGETED NANOPORE SEQUENCING REVEALS EPIGENETIC HETEROGENEITY AFTER DE NOVO ASSEMBLY OF NATIVE FULL-LENGTH HEPATITIS B VIRUS GENOMES. HEPATITIS B VIRUS (HBV) CONTAINS A 3.2 KB DNA GENOME AND CAUSES ACUTE AND CHRONIC HEPATITIS. HBV INFECTION IS A GLOBAL HEALTH PROBLEM, WITH 350 MILLION CHRONICALLY INFECTED PEOPLE AT INCREASED RISK OF DEVELOPING LIVER DISEASE AND HEPATOCELLULAR CARCINOMA (HCC). METHYLATION OF HBV DNA IN A CPG CONTEXT (5MCPG) CAN ALTER THE EXPRESSION PATTERNS OF VIRAL GENES RELATED TO INFECTION AND CELLULAR TRANSFORMATION. MOREOVER, IT MAY ALSO PROVIDE CLUES AS TO WHY CERTAIN INFECTIONS ARE CLEARED OR PERSIST WITH OR WITHOUT PROGRESSION TO CANCER. THE DETECTION OF 5MCPG OFTEN REQUIRES TECHNIQUES THAT DAMAGE DNA OR INTRODUCE BIAS THROUGH A MYRIAD OF LIMITATIONS. THEREFORE, WE DEVELOPED A METHOD FOR THE DETECTION OF 5MCPG ON THE HBV GENOME THAT DOES NOT RELY ON BISULFITE CONVERSION OR PCR. WITH CAS9-GUIDED RNPS TO SPECIFICALLY TARGET THE HBV GENOME, WE ENRICHED IN HBV DNA FROM PRIMARY HUMAN HEPATOCYTES (PHHS) INFECTED WITH DIFFERENT HBV GENOTYPES, AS WELL AS ENRICHING IN HBV FROM INFECTED PATIENT LIVER TISSUE, FOLLOWED BY SEQUENCING WITH OXFORD NANOPORE TECHNOLOGIES MINION. DETECTION OF 5MCPG BY NANOPORE SEQUENCING WAS BENCHMARKED WITH BISULFITE-QUANTITATIVE METHYL-SPECIFIC QPCR (BS-QMSP). THE 5MCPG LEVELS IN HBV DETERMINED BY BS-QMSP AND NANOPORE SEQUENCING WERE HIGHLY CORRELATED. OUR NANOPORE SEQUENCING APPROACH ACHIEVED A COVERAGE OF ~2000X OF HBV DEPENDING ON INFECTION EFFICIENCY, SUFFICIENT COVERAGE TO PERFORM A DE NOVO ASSEMBLY AND DETECT SMALL FLUCTUATIONS IN HBV METHYLATION, PROVIDING THE FIRST DE NOVO ASSEMBLY OF NATIVE HBV DNA, AS WELL AS THE FIRST LANDSCAPE OF 5MCPG FROM NATIVE HBV SEQUENCES. MOREOVER, BY CAPTURING ENTIRE HBV GENOMES, WE EXPLORED THE EPIGENETIC HETEROGENEITY OF HBV IN INFECTED PATIENTS AND IDENTIFIED FOUR EPIGENETICALLY DISTINCT CLUSTERS BASED ON METHYLATION PROFILES. THIS METHOD IS A NOVEL APPROACH THAT ENABLES THE ENRICHMENT OF VIRAL DNA IN A MIXTURE OF NUCLEIC ACID MATERIAL FROM DIFFERENT SPECIES AND WILL SERVE AS A VALUABLE TOOL FOR INFECTIOUS DISEASE MONITORING. 2021 17 3247 30 HEPATITIS B VIRUS BASAL CORE PROMOTER MUTATIONS SHOW LOWER REPLICATION FITNESS ASSOCIATED WITH CCCDNA ACETYLATION STATUS. IN CHRONIC HEPATITIS B VIRUS (HBV) INFECTION, VARIANTS WITH MUTATIONS IN THE BASAL CORE PROMOTER (BCP) AND PRECORE REGION PREDOMINATE AND ASSOCIATE WITH MORE SEVERE DISEASE FORMS. STUDIES ON THEIR EFFECT ON VIRAL REPLICATION REMAIN CONTROVERSIAL. INCREASING EVIDENCE SHOWS THAT EPIGENETIC MODIFICATIONS OF CCCDNA REGULATE HBV REPLICATION AND DISEASE OUTCOME. HERE WE DETERMINED THE TRANSCRIPTION AND VIRAL REPLICATION EFFICIENCY OF WELL-DEFINED BCP AND PRECORE MUTATIONS AND THEIR EFFECT ON CCCDNA EPIGENETIC CONTROL. HBV MONOMERS BEARING BCP MUTATIONS A1762T/G1764A AND A1762T/G1764A/C1766T, AND PRECORE MUTATIONS G1896A, G1899A AND G1896A/G1899A, WERE TRANSFECTED INTO HEPG2 CELLS USING A PLASMID-FREE APPROACH. VIRAL RNA TRANSCRIPTS WERE DETECTED BY NORTHERN BLOT HYBRIDIZATION AND RT PCR, DNA REPLICATIVE INTERMEDIATES BY SOUTHERN BLOTTING AND RT PCR, AND VIRAL RELEASE WAS MEASURED BY ELISA. ACETYLATION OF CCCDNA-BOUND HISTONES WAS ASSESSED BY CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAY AND METHYLATION OF CCCDNA BY BISULFITE SEQUENCING. BCP MUTATIONS RESULTED IN LOW VIRAL RELEASE, MRNA TRANSCRIPTION AND PGRNA/CCCDNA RATIOS THAT PARALLELED THE ACETYLATION OF CCCDNA-BOUND H4 HISTONE AND INVERSELY CORRELATED WITH THE HDAC1 RECRUITMENT ONTO CCCDNA. INDEPENDENTLY OF THE MUTATIONS, CCCDNA WAS A TARGET FOR METHYLATION, ACCOMPANIED BY THE UPREGULATION OF DNMT1 EXPRESSION AND DNMT1 RECRUITMENT ONTO CCCDNA. OUR RESULTS SUGGEST THAT BCP MUTATIONS DECREASE VIRAL REPLICATION CAPACITY POSSIBLY BY MODULATING THE ACETYLATION AND DEACETYLATION OF CCCDNA-BOUND HISTONES WHILE PRECORE MUTATIONS DO NOT HAVE A SIGNIFICANT EFFECT ON VIRAL REPLICATION. THESE DATA PROVIDE EVIDENCE THAT EPIGENETIC FACTORS CONTRIBUTE TO THE REGULATION OF HBV VIRAL REPLICATION. 2016 18 5844 32 STUDY OF PROMOTER HYPOMETHYLATION PROFILES OF RAS ONCOGENES IN HEPATOCELLULAR CARCINOMA DERIVED FROM HEPATITIS C VIRUS GENOTYPE 3A IN PAKISTANI POPULATION. EPIGENETIC MODIFICATIONS SUCH AS DNA METHYLATION CONTRIBUTE TO PROGRESSION OF HEPATITIS C VIRUS (HCV) INFECTION TO LIFE-THREATENING HEPATOCELLULAR CARCINOMA (HCC) BY PROMOTING THE SILENCING OF TUMOR SUPPRESSOR GENES THROUGH DNA HYPERMETHYLATION AND BY CAUSING GENOMIC INSTABILITY THROUGH GLOBAL HYPOMETHYLATION. HOWEVER FEW STUDIES HAVE ADDRESSED THE PROMOTER REGION HYPOMETHYLATION STATUS OF THE ONCOGENES INVOLVED IN HCV DERIVED HCC. IN THIS STUDY, WE ANALYZED THE PROMOTER REGION METHYLATION PATTERN OF RAS ONCOGENES (HRAS, KRAS, AND NRAS) USING METHYLATION-SPECIFIC PCR FOR 50 CHRONIC HCV PATIENTS INFECTED WITH GENOTYPE 3A (27 HCC PATIENTS AND 23 CONTROL NON-HCC PATIENTS). METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION ANALYSIS REVEALED THAT THE NRAS ONCOGENE PROMOTER (P = .0025) WAS SIGNIFICANTLY HYPOMETHYLATED IN HCC PATIENTS COMPARED TO THE NON-HCC PATIENTS SUGGESTING ITS CONTRIBUTION TO THE PROGRESSION OF HCV TOWARDS HCC. TO IDENTIFY THE AGENT FOR ALTERATION IN THE RAS ONCOGENE EXPRESSION, 7 HCV GENES WERE EXPRESSED IN THE HUH-7 CELL LINE FOLLOWED BY MEASUREMENT OF THE NRAS EXPRESSION LEVEL IN HUH-7 BY A QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION. AN INCREASE IN THE MESSENGER RNA LEVEL OF THE NRAS GENE WAS DETECTED WHEN HUH-7 WERE TRANSFECTED WITH CORE, NS5A, AND NS2 GENES. OUR FINDINGS SUGGEST THE INVOLVEMENT OF NRAS ONCOGENE IN THE PATHOGENESIS OF HCV3A DERIVED HCC IN PAKISTANI POPULATION AND ALSO IDENTIFIES THE HCV GENES RESPONSIBLE FOR ITS ENHANCED EXPRESSION. OUR STUDY RAISES THE HYPOTHESIS THAT A SINGLE HCV GENE MAY INCREASE THE CHANCES OF MALIGNANCY. THEREFORE, OUR STUDY MAY HAVE IDENTIFIED A USEFUL EPIGENETIC BIOMARKER OF HCC PROGRESSION IN HCV PATIENTS AND MAY HELP TO DEVELOP NOVEL DIAGNOSTIC TOOLS. 2018 19 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 20 6448 30 THERAPEUTIC SHUTDOWN OF HBV TRANSCRIPTS PROMOTES REAPPEARANCE OF THE SMC5/6 COMPLEX AND SILENCING OF THE VIRAL GENOME IN VIVO. OBJECTIVE: THERAPEUTIC STRATEGIES SILENCING AND REDUCING THE HEPATITIS B VIRUS (HBV) RESERVOIR, THE COVALENTLY CLOSED CIRCULAR DNA (CCCDNA), HAVE THE POTENTIAL TO CURE CHRONIC HBV INFECTION. WE AIMED TO INVESTIGATE THE IMPACT OF SMALL INTERFERRING RNA (SIRNA) TARGETING ALL HBV TRANSCRIPTS OR PEGYLATED INTERFERON-ALPHA (PEG-IFNALPHA) ON THE VIRAL REGULATORY HBX PROTEIN AND THE STRUCTURAL MAINTENANCE OF CHROMOSOME 5/6 COMPLEX (SMC5/6), A HOST FACTOR SUPPRESSING CCCDNA TRANSCRIPTION. IN PARTICULAR, WE ASSESSED WHETHER INTERVENTIONS LOWERING HBV TRANSCRIPTS CAN ACHIEVE AND MAINTAIN SILENCING OF CCCDNA TRANSCRIPTION IN VIVO. DESIGN: HBV-INFECTED HUMAN LIVER CHIMERIC MICE WERE TREATED WITH SIRNA OR PEG-IFNALPHA. VIROLOGICAL AND HOST CHANGES WERE ANALYSED AT THE END OF TREATMENT AND DURING THE REBOUND PHASE BY QUALITATIVE PCR, ELISA, IMMUNOBLOTTING AND CHROMATIN IMMUNOPRECIPITATION. RNA IN SITU HYBRIDISATION WAS COMBINED WITH IMMUNOFLUORESCENCE TO DETECT SMC6 AND HBV RNAS AT SINGLE CELL LEVEL. THE ENTRY INHIBITOR MYRCLUDEX-B WAS USED DURING THE REBOUND PHASE TO AVOID NEW INFECTION EVENTS. RESULTS: BOTH SIRNA AND PEG-IFNALPHA STRONGLY REDUCED ALL HBV MARKERS, INCLUDING HBX LEVELS, THUS ENABLING THE REAPPEARANCE OF SMC5/6 IN HEPATOCYTES THAT ACHIEVED HBV-RNA NEGATIVISATION AND SMC5/6 ASSOCIATION WITH THE CCCDNA. ONLY IFN REDUCED CCCDNA LOADS AND ENHANCED IFN-STIMULATED GENES. HOWEVER, THE ANTIVIRAL EFFECTS DID NOT PERSIST OFF TREATMENT AND SMC5/6 WAS AGAIN DEGRADED. REMARKABLY, THE BLOCKADE OF VIRAL ENTRY THAT STARTED AT THE END OF TREATMENT HINDERED RENEWED DEGRADATION OF SMC5/6. CONCLUSION: THESE RESULTS REVEAL THAT THERAPEUTICS ABROGATING ALL HBV TRANSCRIPTS INCLUDING HBX PROMOTE EPIGENETIC SUPPRESSION OF THE HBV MINICHROMOSOME, WHEREAS STRATEGIES PROTECTING THE HUMAN HEPATOCYTES FROM REINFECTION ARE NEEDED TO MAINTAIN CCCDNA SILENCING. 2022