1 3190 146 HCV-INDUCED EPIGENETIC CHANGES ASSOCIATED WITH LIVER CANCER RISK PERSIST AFTER SUSTAINED VIROLOGIC RESPONSE. BACKGROUND & AIMS: CHRONIC HEPATITIS C VIRUS (HCV) INFECTION IS AN IMPORTANT RISK FACTOR FOR HEPATOCELLULAR CARCINOMA (HCC). DESPITE EFFECTIVE ANTIVIRAL THERAPIES, THE RISK FOR HCC IS DECREASED BUT NOT ELIMINATED AFTER A SUSTAINED VIROLOGIC RESPONSE (SVR) TO DIRECT-ACTING ANTIVIRAL (DAA) AGENTS, AND THE RISK IS HIGHER IN PATIENTS WITH ADVANCED FIBROSIS. WE INVESTIGATED HCV-INDUCED EPIGENETIC ALTERATIONS THAT MIGHT AFFECT RISK FOR HCC AFTER DAA TREATMENT IN PATIENTS AND MICE WITH HUMANIZED LIVERS. METHODS: WE PERFORMED GENOME-WIDE CHIPMENTATION-BASED CHIP-SEQ AND RNA-SEQ ANALYSES OF LIVER TISSUES FROM 6 PATIENTS WITHOUT HCV INFECTION (CONTROLS), 18 PATIENTS WITH CHRONIC HCV INFECTION, 8 PATIENTS WITH CHRONIC HCV INFECTION CURED BY DAA TREATMENT, 13 PATIENTS WITH CHRONIC HCV INFECTION CURED BY INTERFERON THERAPY, 4 PATIENTS WITH CHRONIC HEPATITIS B VIRUS INFECTION, AND 7 PATIENTS WITH NONALCOHOLIC STEATOHEPATITIS IN EUROPE AND JAPAN. HCV-INDUCED EPIGENETIC MODIFICATIONS WERE MAPPED BY COMPARATIVE ANALYSES WITH MODIFICATIONS ASSOCIATED WITH OTHER LIVER DISEASE ETIOLOGIES. UPA/SCID MICE WERE ENGRAFTED WITH HUMAN HEPATOCYTES TO CREATE MICE WITH HUMANIZED LIVERS AND GIVEN INJECTIONS OF HCV-INFECTED SERUM SAMPLES FROM PATIENTS; MICE WERE GIVEN DAAS TO ERADICATE THE VIRUS. PATHWAYS ASSOCIATED WITH HCC RISK WERE IDENTIFIED BY INTEGRATIVE PATHWAY ANALYSES AND VALIDATED IN ANALYSES OF PAIRED HCC TISSUES FROM 8 PATIENTS WITH AN SVR TO DAA TREATMENT OF HCV INFECTION. RESULTS: WE FOUND CHRONIC HCV INFECTION TO INDUCE SPECIFIC GENOME-WIDE CHANGES IN H3K27AC, WHICH CORRELATED WITH CHANGES IN EXPRESSION OF MRNAS AND PROTEINS. THESE CHANGES PERSISTED AFTER AN SVR TO DAAS OR INTERFERON-BASED THERAPIES. INTEGRATIVE PATHWAY ANALYSES OF LIVER TISSUES FROM PATIENTS AND MICE WITH HUMANIZED LIVERS DEMONSTRATED THAT HCV-INDUCED EPIGENETIC ALTERATIONS WERE ASSOCIATED WITH LIVER CANCER RISK. COMPUTATIONAL ANALYSES ASSOCIATED INCREASED EXPRESSION OF SPHK1 WITH HCC RISK. WE VALIDATED THESE FINDINGS IN AN INDEPENDENT COHORT OF PATIENTS WITH HCV-RELATED CIRRHOSIS (N = 216), A SUBSET OF WHICH (N = 21) ACHIEVED VIRAL CLEARANCE. CONCLUSIONS: IN AN ANALYSIS OF LIVER TISSUES FROM PATIENTS WITH AND WITHOUT AN SVR TO DAA THERAPY, WE IDENTIFIED EPIGENETIC AND GENE EXPRESSION ALTERATIONS ASSOCIATED WITH RISK FOR HCC. THESE ALTERATIONS MIGHT BE TARGETED TO PREVENT LIVER CANCER IN PATIENTS TREATED FOR HCV INFECTION. 2019 2 5521 50 RISK OF HEPATOCELLULAR CARCINOMA AFTER HCV CLEARANCE BY DIRECT-ACTING ANTIVIRALS TREATMENT PREDICTIVE FACTORS AND ROLE OF EPIGENETICS. DIRECT-ACTING ANTIVIRALS (DAAS) INDUCE A RAPID VIROLOGIC RESPONSE (SVR) IN UP TO 99% OF CHRONIC HEPATITIS C PATIENTS. THE ROLE OF SVR BY DAAS ON THE INCIDENCE OR RECURRENCE OF HEPATOCELLULAR CARCINOMA (HCC) IS STILL A MATTER OF DEBATE, ALTHOUGH IT IS KNOWN THAT SVR DOES NOT ELIMINATE THE RISK OF HCC. IN THIS REVIEW, WE MADE AN UPDATED ANALYSIS OF THE LITERATURE DATA ON THE IMPACT OF SVR BY DAAS ON THE RISK OF HCC AS WELL AS AN ASSESSMENT OF RISK FACTORS AND THE ROLE OF EPIGENETICS. DATA SHOWED THAT SVR HAS NO IMPACT ON THE OCCURRENCE OF HCC IN THE SHORT-MEDIUM TERM BUT REDUCES THE RISK OF HCC IN THE MEDIUM-LONG TERM. A DIRECT ROLE OF DAAS IN THE DEVELOPMENT OF HCC HAS NOT BEEN DEMONSTRATED, WHILE THE HYPOTHESIS OF A REDUCTION IN IMMUNE SURVEILLANCE IN RESPONSE TO THE RAPID CLEARANCE OF HCV AND CHANGES IN THE CYTOKINE PATTERN INFLUENCING EARLY CARCINOGENESIS REMAINS TO BE FURTHER ELUCIDATED. HCV INDUCES EPIGENETIC ALTERATIONS SUCH AS MODIFICATIONS OF THE HISTONE TAIL AND DNA METHYLATION, WHICH ARE RISK FACTORS FOR HCC, AND SUCH CHANGES ARE MAINTAINED AFTER HCV CLEARANCE. FUTURE EPIGENETIC STUDIES COULD LEAD TO IDENTIFY USEFUL BIOMARKERS AND THERAPEUTIC TARGETS. CIRRHOSIS HAS BEEN IDENTIFIED AS A RISK FACTOR FOR HCC, PARTICULARLY IF ASSOCIATED WITH HIGH LIVER STIFFNESS AND ALPHA-FETOPROTEIN VALUES, DIABETES AND THE MALE SEX. CURRENTLY, CONSIDERING THE HIGH NUMBER AND HEALTH COST TO FOLLOW SUBJECTS' POST-HCV CLEARANCE BY DAAS, IT IS MANDATORY TO IDENTIFY THOSE AT HIGH RISK OF HCC TO OPTIMIZE MANAGEMENT. 2020 3 5486 57 REVERSE INFLAMMAGING: LONG-TERM EFFECTS OF HCV CURE ON BIOLOGICAL AGE. BACKGROUND & AIMS: CHRONIC HEPATITIS C VIRUS (HCV) INFECTION CAN BE CURED WITH DIRECT-ACTING ANTIVIRALS (DAAS). HOWEVER, NOT ALL SEQUELAE OF CHRONIC HEPATITIS C APPEAR TO BE COMPLETELY REVERSIBLE AFTER SUSTAINED VIROLOGIC RESPONSE (SVR). RECENTLY, CHRONIC VIRAL INFECTIONS HAVE BEEN SHOWN TO BE ASSOCIATED WITH BIOLOGICAL AGE ACCELERATION DEFINED BY THE EPIGENETIC CLOCK. THE AIM OF THIS STUDY WAS TO INVESTIGATE WHETHER CHRONIC HCV INFECTION IS ASSOCIATED WITH EPIGENETIC CHANGES AND BIOLOGICAL AGE ACCELERATION AND WHETHER THIS IS REVERSIBLE AFTER SVR. METHODS: WE INCLUDED 54 WELL-CHARACTERIZED INDIVIDUALS WITH CHRONIC HEPATITIS C WHO ACHIEVED SVR AFTER DAA THERAPY AT THREE TIME POINTS: DAA TREATMENT INITIATION, END OF TREATMENT, AND LONG-TERM FOLLOW-UP (MEDIAN 96 WEEKS AFTER END OF TREATMENT). GENOME-WIDE DNA METHYLATION STATUS WAS DETERMINED IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) AND USED TO CALCULATE EPIGENETIC AGE ACCELERATION (EAA) USING HORVATH'S CLOCK. RESULTS: INDIVIDUALS WITH HCV HAD AN OVERALL SIGNIFICANT EAA OF 3.12 YEARS AT BASELINE COMPARED WITH -2.61 YEARS IN THE AGE- AND SEX-MATCHED REFERENCE GROUP (P <0.00003). HCV ELIMINATION RESULTED IN A SIGNIFICANT LONG-TERM INCREASE IN DNA METHYLATION DOMINATED BY HYPERMETHYLATED CPGS IN ALL PATIENT GROUPS. ACCORDINGLY, EAA DECREASED TO 1.37 YEARS AT LONG-TERM FOLLOW-UP. THE DECREASE IN EAA WAS SIGNIFICANT ONLY BETWEEN THE END OF TREATMENT AND FOLLOW-UP (P = 0.01). INTERESTINGLY, EIGHT INDIVIDUALS WHO DEVELOPED HEPATOCELLULAR CARCINOMA AFTER SVR HAD THE HIGHEST EAA AND SHOWED NO EVIDENCE OF REVERSAL AFTER SVR. CONCLUSIONS: OUR DATA CONTRIBUTE TO THE UNDERSTANDING OF THE BIOLOGICAL IMPACT OF HCV ELIMINATION AFTER DAA THERAPY AND DEMONSTRATE THAT HCV ELIMINATION CAN LEAD TO "REVERSE INFLAMMAGING". IN ADDITION, OUR DATA SUPPORT THE POTENTIAL USE OF BIOLOGICAL AGE AS A BIOMARKER FOR HCV SEQUELAE AFTER SVR. IMPACT AND IMPLICATIONS: CHRONIC HEPATITIS C VIRUS INFECTION IS NOW CURABLE WITH DIRECT-ACTING ANTIVIRALS, BUT IT REMAINS UNCLEAR WHETHER HEPATITIS C SEQUELAE ARE FULLY REVERSIBLE AFTER VIRAL ELIMINATION. OUR RESULTS SUGGEST THAT EPIGENETIC CHANGES OR ACCELERATION OF BIOLOGICAL AGE ARE REVERSIBLE IN PRINCIPLE, BUT THIS REQUIRES TIME, WHILE A LACK OF REVERSIBILITY APPEARS TO BE ASSOCIATED WITH THE DEVELOPMENT OF HEPATOCELLULAR CARCINOMA. WHILE MOST CLINICAL RISK SCORES NOW TAKE CHRONOLOGICAL AGE INTO ACCOUNT, IT MAY BE WORTHWHILE TO EXPLORE HOW BIOLOGICAL AGE MIGHT IMPROVE THESE SCORES IN THE FUTURE. BIOLOGICAL AGE MAY BE A CORNERSTONE FOR THE INDIVIDUALIZED CLINICAL ASSESSMENT OF PATIENTS IN THE FUTURE, AS IT BETTER REFLECTS PATIENTS' LIFESTYLE AND ENVIRONMENTAL EXPOSURES OVER DECADES. 2023 4 3271 47 HEPATOCELLULAR CARCINOMA RISK AFTER VIRAL RESPONSE IN HEPATITIS C VIRUS-ADVANCED FIBROSIS: WHO TO SCREEN AND FOR HOW LONG? HEPATITIS C VIRUS (HCV) CHRONIC INFECTION IS ASSOCIATED WITH FIBROSIS PROGRESSION, END-STAGE LIVER COMPLICATIONS AND HCC. NOT SURPRISINGLY, HCV INFECTION IS A LEADING CAUSE OF LIVER-RELATED MORBIDITY AND MORTALITY WORLDWIDE. AFTER SUSTAINED VIROLOGICAL RESPONSE (SVR), THE RISK OF DEVELOPING HEPATOCELLULAR CARCINOMA IS NOT COMPLETELY ELIMINATED IN PATIENTS WITH ESTABLISHED CIRRHOSIS OR WITH ADVANCED FIBROSIS. THEREFORE, LIFELONG SURVEILLANCE IS CURRENTLY RECOMMENDED. THIS STRATEGY IS LIKELY NOT UNIVERSALLY COST-EFFECTIVE AND HARMLESS, CONSIDERING THAT NOT ALL PATIENTS WITH ADVANCED FIBROSIS HAVE THE SAME RISK OF DEVELOPING HCC. FACTORS RELATED TO THE SEVERITY OF LIVER DISEASE AND ITS POTENTIAL TO IMPROVE AFTER SVR, THE MOLECULAR AND EPIGENETIC CHANGES THAT OCCUR DURING INFECTION AND OTHER ASSOCIATED COMORBIDITIES MIGHT ACCOUNT FOR DIFFERENT RISK LEVELS AND ARE LIKELY ESSENTIAL FOR IDENTIFYING PATIENTS WHO WOULD BENEFIT FROM SCREENING PROGRAMS AFTER SVR. EFFORTS TO DEVELOP PREDICTIVE MODELS AND RISK CALCULATORS, BIOMARKERS AND GENETIC PANELS AND EVEN DEEP LEARNING MODELS TO ESTIMATE THE INDIVIDUAL RISK OF HCC HAVE BEEN MADE IN THE DIRECT-ACTING ANTIVIRAL AGENTS ERA, WHEN THOUSANDS OF PATIENTS WITH ADVANCED FIBROSIS AND CIRRHOSIS HAVE REACHED SVR. THESE TOOLS COULD HELP TO IDENTIFY PATIENTS WITH VERY LOW HCC RISK IN WHOM SURVEILLANCE MIGHT NOT BE JUSTIFIED. IN THIS REVIEW, FACTORS AFFECTING THE PROBABILITY OF HCC DEVELOPMENT AFTER SVR, THE BENEFITS AND RISKS OF SURVEILLANCE, SUGGESTED STRATEGIES TO ESTIMATE INDIVIDUALIZED HCC RISK AND THE CURRENT EVIDENCE TO RECOMMEND LIFELONG SURVEILLANCE ARE DISCUSSED. 2021 5 3260 63 HEPATITIS C VIRUS LEAVES AN EPIGENETIC SIGNATURE POST CURE OF INFECTION BY DIRECT-ACTING ANTIVIRALS. THE INCREASING WORLDWIDE PREVALENCE OF HEPATOCELLULAR CARCINOMA (HCC), CHARACTERIZED BY RESISTANCE TO CONVENTIONAL CHEMOTHERAPY, POOR PROGNOSIS AND EVENTUALLY MORTALITY, PLACE IT AS A PRIME TARGET FOR NEW MODES OF PREVENTION AND TREATMENT. HEPATITIS C VIRUS (HCV) IS THE PREDOMINANT RISK FACTOR FOR HCC IN THE US AND EUROPE. MULTIPLE EPIDEMIOLOGICAL STUDIES SHOWED THAT SUSTAINED VIROLOGICAL RESPONSES (SVR) FOLLOWING TREATMENT WITH THE POWERFUL DIRECT ACTING ANTIVIRALS (DAAS), WHICH HAVE REPLACED INTERFERON-BASED REGIMES, DO NOT ELIMINATE TUMOR DEVELOPMENT. WE AIMED TO IDENTIFY AN HCV-SPECIFIC PATHOGENIC MECHANISM THAT PERSISTS POST SVR FOLLOWING DAAS TREATMENT. WE DEMONSTRATE THAT HCV INFECTION INDUCES GENOME-WIDE EPIGENETIC CHANGES BY PERFORMING CHROMATIN IMMUNOPRECIPITATION FOLLOWED BY NEXT-GENERATION SEQUENCING (CHIP-SEQ) FOR HISTONE POST-TRANSLATIONAL MODIFICATIONS THAT ARE EPIGENETIC MARKERS FOR ACTIVE AND REPRESSED CHROMATIN. THE CHANGES IN HISTONE MODIFICATIONS CORRELATE WITH REPROGRAMED HOST GENE EXPRESSION AND ALTER SIGNALING PATHWAYS KNOWN TO BE ASSOCIATED WITH HCV LIFE CYCLE AND HCC. THESE EPIGENETIC ALTERATIONS REQUIRE THE PRESENCE OF HCV RNA OR/AND EXPRESSION OF THE VIRAL PROTEINS IN THE CELLS. IMPORTANTLY, THE EPIGENETIC CHANGES INDUCED FOLLOWING INFECTION PERSIST AS AN "EPIGENETIC SIGNATURE" AFTER VIRUS ERADICATION BY DAAS TREATMENT, AS DETECTED USING IN VITRO HCV INFECTION MODELS. THESE OBSERVATIONS LED TO THE IDENTIFICATION OF AN 8 GENE SIGNATURE THAT IS ASSOCIATED WITH HCC DEVELOPMENT AND DEMONSTRATE PERSISTENT EPIGENETIC ALTERATIONS IN HCV INFECTED AND POST SVR LIVER BIOPSY SAMPLES. THE EPIGENETIC SIGNATURE WAS REVERTED IN VITRO BY DRUGS THAT INHIBIT EPIGENETIC MODIFYING ENZYME AND BY THE EGFR INHIBITOR, ERLOTINIB. THIS EPIGENETIC "SCARRING" OF THE GENOME, PERSISTING FOLLOWING HCV ERADICATION, SUGGEST A NOVEL MECHANISM FOR THE PERSISTENT PATHOGENESIS OF HCV AFTER ITS ERADICATION BY DAAS. OUR STUDY OFFERS NEW AVENUES FOR PREVENTION OF THE PERSISTENT ONCOGENIC EFFECTS OF CHRONIC HEPATITIS INFECTIONS USING SPECIFIC DRUGS TO REVERT THE EPIGENETIC CHANGES TO THE GENOME. 2019 6 1042 37 CLINICAL AND MOLECULAR BASIS OF HEPATOCELLULAR CARCINOMA AFTER HEPATITIS C VIRUS ERADICATION. HEPATOCELLULAR CARCINOMA (HCC) ARISES IN THE BACKGROUND OF CHRONIC LIVER DISEASES, INCLUDING HEPATITIS AND LIVER CIRRHOSIS CAUSED BY HEPATITIS C VIRUS (HCV) INFECTION. IT IS WELL KNOWN THAT HCV ERADICATION USING ANTIVIRAL DRUGS CAN EFFICIENTLY INHIBIT HEPATOCARCINOGENESIS. RECENT ADVANCES IN AND DEVELOPMENT OF DIRECT-ACTING ANTIVIRAL (DAA) DRUGS HAS REVOLUTIONIZED THE TREATMENT OF HCV INFECTION, AND THE VAST MAJORITY OF HCV PATIENTS CAN ACHIEVE HCV ERADICATION USING DAAS. HOWEVER, MOUNTING EVIDENCE CLEARLY INDICATES THAT HCC INEVITABLY OCCURS IN A SUBSET OF PATIENTS AFTER SUCCESSFUL VIRAL ERADICATION USING DAA THERAPY. CANCER IS A GENETIC DISEASE, AND THE ACCUMULATION OF GENETIC AND EPIGENETIC ABERRATIONS MAY CAUSE HEPATOCARCINOGENESIS IN CHRONICALLY DAMAGED LIVER, EVEN AFTER VIRUS ELIMINATION. IN THIS REVIEW, WE HIGHLIGHT HCC DEVELOPMENT AFTER HCV ERADICATION AND DISCUSS THE CURRENT UNDERSTANDING OF THE MOLECULAR MECHANISMS OF TUMORIGENESIS AFTER VIRUS ELIMINATION, FOCUSING ON THE GENETIC AND EPIGENETIC BACKGROUND OF CHRONICALLY DAMAGED LIVER TISSUES. 2022 7 4903 38 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 8 3780 54 INTERFERON DRIVES HCV SCARRING OF THE EPIGENOME AND CREATES TARGETABLE VULNERABILITIES FOLLOWING VIRAL CLEARANCE. BACKGROUND AND AIMS: CHRONIC HCV INFECTION IS A LEADING ETIOLOGIC DRIVER OF CIRRHOSIS AND ULTIMATELY HCC. OF THE APPROXIMATELY 71 MILLION INDIVIDUALS CHRONICALLY INFECTED WITH HCV, 10%-20% ARE EXPECTED TO DEVELOP SEVERE LIVER COMPLICATIONS IN THEIR LIFETIME. EPIGENETIC MECHANISMS INCLUDING DNA METHYLATION AND HISTONE MODIFICATIONS BECOME PROFOUNDLY DISRUPTED IN DISEASE PROCESSES INCLUDING LIVER DISEASE. APPROACH AND RESULTS: TO UNDERSTAND HOW HCV INFECTION INFLUENCES THE EPIGENOME AND WHETHER THESE EVENTS REMAIN AS "SCARS" FOLLOWING CURE OF CHRONIC HCV INFECTION, WE MAPPED GENOME-WIDE DNA METHYLATION, FOUR KEY REGULATORY HISTONE MODIFICATIONS (H3K4ME3, H3K4ME1, H3K27AC, AND H3K27ME3), AND OPEN CHROMATIN IN PARENTAL AND HCV-INFECTED IMMORTALIZED HEPATOCYTES AND THE HUH7.5 HCC CELL LINE, ALONG WITH DNA METHYLATION AND GENE-EXPRESSION ANALYSES FOLLOWING ELIMINATION OF HCV IN THESE MODELS THROUGH TREATMENT WITH INTERFERON-ALPHA (IFN-ALPHA) OR A DIRECT-ACTING ANTIVIRAL (DAA). OUR DATA DEMONSTRATE THAT HCV INFECTION PROFOUNDLY AFFECTS THE EPIGENOME (PARTICULARLY ENHANCERS); HCV SHARES EPIGENETIC TARGETS WITH INTERFERON-ALPHA TARGETS; AND AN OVERWHELMING MAJORITY OF EPIGENETIC CHANGES INDUCED BY HCV REMAIN AS "SCARS" ON THE EPIGENOME FOLLOWING VIRAL CURE. SIMILAR FINDINGS ARE OBSERVED IN PRIMARY HUMAN PATIENT SAMPLES CURED OF CHRONIC HCV INFECTION. SUPPLEMENTATION OF IFN-ALPHA/DAA ANTIVIRAL REGIMENS WITH DNA METHYLTRANSFERASE INHIBITOR 5-AZA-2'-DEOXYCYTIDINE SYNERGIZES IN REVERTING ABERRANT DNA METHYLATION INDUCED BY HCV. FINALLY, BOTH HCV-INFECTED AND CURED CELLS DISPLAYED A BLUNTED IMMUNE RESPONSE, DEMONSTRATING A FUNCTIONAL EFFECT OF EPIGENETIC SCARRING. CONCLUSIONS: INTEGRATION OF EPIGENETIC AND TRANSCRIPTIONAL DATA ELUCIDATE KEY GENE DEREGULATION EVENTS DRIVEN BY HCV INFECTION AND HOW THIS MAY UNDERPIN THE LONG-TERM ELEVATED RISK FOR HCC IN PATIENTS CURED OF HCV DUE TO EPIGENOME SCARRING. 2022 9 442 35 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 10 3259 38 HEPATITIS C VIRUS AND HEPATOCELLULAR CARCINOMA: WHEN THE HOST LOSES ITS GRIP. CHRONIC INFECTION WITH HEPATITIS C VIRUS (HCV) IS A MAJOR CAUSE OF HEPATOCELLULAR CARCINOMA (HCC). NOVEL TREATMENTS WITH DIRECT-ACTING ANTIVIRALS ACHIEVE HIGH RATES OF SUSTAINED VIROLOGIC RESPONSE; HOWEVER, THE HCC RISK REMAINS ELEVATED IN CURED PATIENTS, ESPECIALLY THOSE WITH ADVANCED LIVER DISEASE. LONG-TERM HCV INFECTION CAUSES A PERSISTENT AND ACCUMULATING DAMAGE OF THE LIVER DUE TO A COMBINATION OF DIRECT AND INDIRECT PRO-ONCOGENIC MECHANISMS. THIS REVIEW DESCRIBES THE PROCESSES INVOLVED IN VIRUS-INDUCED DISEASE PROGRESSION BY VIRAL PROTEINS, DERAILED SIGNALING, IMMUNITY, AND PERSISTENT EPIGENETIC DEREGULATION, WHICH MAY BE INSTRUMENTAL TO DEVELOP URGENTLY NEEDED PROGNOSTIC BIOMARKERS AND AS TARGETS FOR NOVEL CHEMOPREVENTIVE THERAPIES. 2020 11 42 49 A COMPREHENSIVE GENOME-WIDE PROFILING COMPARISON BETWEEN HBV AND HCV INFECTED HEPATOCELLULAR CARCINOMA. BACKGROUND: HEPATOCELLULAR CARCINOMA (HCC) IS ONE OF THE MOST COMMON CANCERS WORLDWIDE, ESPECIALLY IN EAST ASIA. EVEN WITH THE PROGRESS IN THERAPY, 5-YEAR SURVIVAL RATES REMAIN UNSATISFIED. CHRONIC INFECTION WITH THE HEPATITIS B VIRUS (HBV) OR HEPATITIS C VIRUS (HCV) HAS BEEN EPIDEMIOLOGICALLY ASSOCIATED WITH HCC AND IS THE MAJOR ETIOLOGY IN THE EAST ASIAN POPULATION. THE DETAILED MECHANISM, ESPECIALLY THE CHANGES OF DNA METHYLATION AND GENE EXPRESSION BETWEEN THE TWO TYPES OF VIRUS-RELATED HCC, AND THEIR CONTRIBUTIONS TO THE HCC DEVELOPMENT, METASTASIS, AND RECURRENCE REMAIN LARGELY UNKNOWN. METHODS: IN THIS INTEGRATED ANALYSIS, WE CHARACTERIZED GENOME-SCALE PROFILES OF HBV AND HCV INFECTED HCC BY COMPARING THEIR GENE EXPRESSION PATTERN, METHYLATION PROFILES, AND COPY NUMBER VARIATIONS FROM THE PUBLICLY ACCESSIBLE DATA OF THE CANCER GENOME ATLAS PROGRAM (TCGA). RESULTS: THE HLA-A, STAT1, AND OAS2 GENES WERE HIGHLY ENRICHED AND UP-REGULATED DISCOVERED IN THE HCV-INFECTED HCC. HYPOMETHYLATION BUT NOT COPY NUMBER VARIATIONS MIGHT BE THE MAJOR FACTOR FOR THE UP-REGULATION OF THESE IMMUNE-RELATED GENES IN HCV-INFECTED HCC. CONCLUSIONS: THE RESULTS INDICATED THE DIFFERENT EPIGENETIC CHANGES OF HBV/HCV RELATED HEPATOCARCINOGENESIS. THE TOP UP-REGULATED GENES IN HCV GROUP WERE SIGNIFICANTLY CLUSTERED IN THE IMMUNE-RELATED AND DEFENSE RESPONSE PATHWAYS. THESE FINDINGS WILL HELP US TO UNDERSTAND THE PATHOGENESIS OF HBV/HCV ASSOCIATED HEPATOCELLULAR CARCINOMA. 2019 12 1506 42 DNA METHYLATION AND IMMUNE CELL MARKERS DEMONSTRATE EVIDENCE OF ACCELERATED AGING IN PATIENTS WITH CHRONIC HEPATITIS B VIRUS OR HEPATITIS C VIRUS, WITH OR WITHOUT HUMAN IMMUNODEFICIENCT VIRUS CO-INFECTION. BACKGROUND: SEVERAL CHRONIC DISEASES ACCELERATE BIOLOGICAL AGING. WE INVESTIGATED AGE ACCELERATION AND THE ASSOCIATION BETWEEN PERIPHERAL BLOOD DNA METHYLATION (DNAM) AND IMMUNE CELL MARKERS IN PATIENTS CHRONICALLY INFECTED WITH THE HEPATITIS B VIRUS (HBV) OR THE HEPATITIS C VIRUS (HCV) WITH AND WITHOUT HUMAN IMMUNODEFICIENCY VIRUS (HIV) CO-INFECTION. METHODS: AGE ACCELERATION WAS MEASURED AS THE DIFFERENCE BETWEEN EPIGENETIC AGE (HORVATH CLOCK) AND CHRONOLOGICAL AGE. THE IMMUNE MARKER MODEL OF AGE ACCELERATION WAS DEVELOPED USING ELASTIC NET REGRESSION TO SELECT BOTH THE IMMUNE MARKERS AND THEIR ASSOCIATED WEIGHTS IN THE FINAL LINEAR MODEL. RESULTS: PATIENTS WITH CHRONIC HBV (N = 51) HAD A SIGNIFICANTLY HIGHER MEDIAN EPIGENETIC AGE COMPARED TO CHRONOLOGICAL AGE (AGE ACCELERATED) (P < .001). IN PATIENTS WITH CHRONIC HCV INFECTION (N = 63), AGE ACCELERATION WAS ASSOCIATED WITH LIVER FIBROSIS AS ASSESSED BY HISTOLOGY (P < .05), OR PRESENCE OF HIV CO-INFECTION (P < .05), BUT NOT HCV MONO-INFECTION. AGE ACCELERATION DEFINED BY IMMUNE MARKERS WAS CONCORDANT WITH AGE ACCELERATION BY DNA METHYLATION (CORRELATION COEFFICIENT = .59 IN HBV; P = .0025). ONE-YEAR TREATMENT OF HBV PATIENTS WITH NUCLEOSIDE THERAPY WAS ASSOCIATED WITH A MODEST REDUCTION IN AGE ACCELERATION, AS MEASURED USING THE IMMUNE MARKER MODEL (-.65 YEARS, P = .018). CONCLUSION: OUR FINDINGS SUGGEST THAT PATIENTS WITH CHRONIC VIRAL HEPATITIS HAVE ACCELERATED EPIGENETIC AGING, THAT IMMUNE MARKERS DEFINE BIOLOGICAL AGE, AND HAVE THE POTENTIAL TO ASSESS THE EFFECTS OF THERAPEUTIC INTERVENTION ON AGE ACCELERATION. 2021 13 4815 46 OCCULT HEPATITIS B INFECTION AND HEPATOCELLULAR CARCINOMA: EPIDEMIOLOGY, VIROLOGY, HEPATOCARCINOGENESIS AND CLINICAL SIGNIFICANCE. OCCULT HEPATITIS B INFECTION (OBI) REFERS TO A CONDITION WHERE REPLICATION-COMPETENT HBV DNA IS PRESENT IN THE LIVER, WITH OR WITHOUT HBV DNA IN THE BLOOD, IN INDIVIDUALS WITH SERUM HBSAG NEGATIVITY ASSESSED BY CURRENTLY AVAILABLE ASSAYS. THE EPISOMAL COVALENTLY CLOSED CIRCULAR DNA (CCCDNA) IN OBI IS IN A LOW REPLICATIVE STATE. VIRAL GENE EXPRESSION IS MEDIATED BY EPIGENETIC CONTROL OF HBV TRANSCRIPTION, INCLUDING THE HBV CPG ISLAND METHYLATION PATHWAY AND POST-TRANSLATIONAL MODIFICATION OF CCCDNA-BOUND HISTONE, WITH A DIFFERENT PATTERN FROM PATIENTS WITH CHRONIC HBV INFECTION. THE PREVALENCE OF OBI VARIES TREMENDOUSLY ACROSS PATIENT POPULATIONS OWING TO NUMEROUS FACTORS, SUCH AS GEOGRAPHIC LOCATION, ASSAY CHARACTERISTICS, HOST IMMUNE RESPONSE, COINFECTION WITH OTHER VIRUSES, AND VACCINATION STATUS. APART FROM THE RISK OF VIRAL REACTIVATION UPON IMMUNOSUPPRESSION AND THE RISK OF TRANSMISSION OF HBV, OBI HAS BEEN IMPLICATED IN HEPATOCELLULAR CARCINOMA (HCC) DEVELOPMENT IN PATIENTS WITH CHRONIC HCV INFECTION, THOSE WITH CRYPTOGENIC OR KNOWN LIVER DISEASE, AND IN PATIENTS WITH HBSAG SEROCLEARANCE AFTER CHRONIC HBV INFECTION. AN INCREASING NUMBER OF PROSPECTIVE STUDIES AND META-ANALYSES HAVE REPORTED A HIGHER INCIDENCE OF HCC IN PATIENTS WITH HCV AND OBI, AS WELL AS MORE ADVANCED TUMOUR HISTOLOGICAL GRADES AND EARLIER AGE OF HCC DIAGNOSIS, COMPARED WITH PATIENTS WITHOUT OBI. THE PROPOSED PATHOGENETIC MECHANISMS OF OBI-RELATED HCC INCLUDE THE INFLUENCE OF HBV DNA INTEGRATION ON THE HEPATOCYTE CELL CYCLE, THE PRODUCTION OF PRO-ONCOGENIC PROTEINS (HBX PROTEIN AND MUTATED SURFACE PROTEINS), AND PERSISTENT LOW-GRADE NECROINFLAMMATION (CONTRIBUTING TO THE DEVELOPMENT OF FIBROSIS AND CIRRHOSIS). THERE REMAIN UNCERTAINTIES ABOUT EXACTLY HOW, AND IN WHAT ORDER, THESE MECHANISMS DRIVE THE DEVELOPMENT OF TUMOURS IN PATIENTS WITH OBI. 2020 14 3476 53 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 6640 47 UNRAVELING THE MOLECULAR MECHANISMS INVOLVED IN HCV-INDUCED CARCINOGENESIS. CANCER INDUCED BY A VIRAL INFECTION IS AMONG THE LEADING CAUSES OF CANCER. HEPATITIS C VIRUS (HCV) IS A HEPATOTROPIC ONCOGENIC POSITIVE-SENSE RNA VIRUS THAT LEADS TO CHRONIC INFECTION, EXPOSING THE LIVER TO A CONTINUOUS PROCESS OF DAMAGE AND REGENERATION AND PROMOTING HEPATOCARCINOGENESIS. THE VIRUS PROMOTES THE DEVELOPMENT OF CARCINOGENESIS THROUGH INDIRECT AND DIRECT MOLECULAR MECHANISMS SUCH AS CHRONIC INFLAMMATION, OXIDATIVE STRESS, STEATOSIS, GENETIC ALTERATIONS, EPITHELIAL-MESENCHYMAL TRANSITION, PROLIFERATION, AND APOPTOSIS, AMONG OTHERS. RECENTLY, DIRECT-ACTING ANTIVIRALS (DAAS) SHOWED SUSTAINED VIROLOGIC RESPONSE IN 95% OF CASES. NEVERTHELESS, PATIENTS TREATED WITH DAAS HAVE REPORTED AN UNEXPECTED INCREASE IN THE EARLY INCIDENCE OF HEPATOCELLULAR CARCINOMA (HCC). STUDIES SUGGEST THAT HCV INDUCES EPIGENETIC REGULATION THROUGH NON-CODING RNAS, DNA METHYLATION, AND CHROMATIN REMODELING, WHICH MODIFY GENE EXPRESSIONS AND INDUCE GENOMIC INSTABILITY RELATED TO HCC DEVELOPMENT THAT PERSISTS WITH THE INFECTION'S CLEARANCE. THE NEED FOR A BETTER UNDERSTANDING OF THE MOLECULAR MECHANISMS ASSOCIATED WITH THE DEVELOPMENT OF CARCINOGENESIS IS EVIDENT. THE AIM OF THIS REVIEW WAS TO UNRAVEL THE MOLECULAR PATHWAYS INVOLVED IN THE DEVELOPMENT OF CARCINOGENESIS BEFORE, DURING, AND AFTER THE VIRAL INFECTION'S RESOLUTION, AND HOW THESE PATHWAYS WERE REGULATED BY THE VIRUS, TO FIND CONTROL POINTS THAT CAN BE USED AS POTENTIAL THERAPEUTIC TARGETS. 2022 16 3927 48 LIVER ABNORMALITIES AFTER ELIMINATION OF HCV INFECTION: PERSISTENT EPIGENETIC AND IMMUNOLOGICAL PERTURBATIONS POST-CURE. CHRONIC HEPATITIS C (CHC) IS A MAJOR CAUSE OF HEPATOCELLULAR CARCINOMA (HCC) WORLDWIDE. WHILE DIRECTLY ACTING ANTIVIRAL (DAA) DRUGS ARE NOW ABLE TO CURE VIRTUALLY ALL HEPATITIS C VIRUS (HCV) INFECTIONS, EVEN IN SUBJECTS WITH ADVANCED LIVER DISEASE, WHAT HAPPENS TO THE LIVER AND PROGRESSION OF THE DISEASE AFTER DAA-INDUCED CURE OF VIREMIA IS ONLY BEGINNING TO EMERGE. SEVERAL LARGE-SCALE CLINICAL STUDIES IN DIFFERENT PATIENT POPULATIONS HAVE SHOWN THAT PATIENTS WITH ADVANCED LIVER DISEASE MAINTAIN A RISK FOR DEVELOPING HCC EVEN WHEN THE ORIGINAL INSTIGATOR, THE VIRUS, IS ELIMINATED BY DAAS. HERE WE REVIEW EMERGING STUDIES DERIVED FROM MULTIPLE, COMPLEMENTARY EXPERIMENTAL SYSTEMS INVOLVING PATIENT LIVER TISSUES, HUMAN LIVER CELL CULTURES, HUMAN LIVER SLICE CULTURES, AND ANIMAL MODELS, SHOWING THAT HCV INFECTION INDUCES EPIGENETIC, SIGNALING, AND GENE EXPRESSION CHANGES IN THE LIVER ASSOCIATED WITH ALTERED HEPATIC INNATE IMMUNITY AND LIVER CANCER RISK. OF CRITICAL IMPORTANCE IS THE FACT THAT THESE VIRUS-INDUCED ABNORMALITIES PERSIST AFTER DAA CURE OF HCV. THESE NASCENT FINDINGS PORTEND THE DISCOVERY OF PATHWAYS INVOLVED IN POST-HCV IMMUNOPATHOGENESIS, WHICH MAY BE CLINICALLY ACTIONABLE TARGETS FOR MORE COMPREHENSIVE CARE OF DAA-CURED INDIVIDUALS. 2021 17 3264 51 HEPATITIS VIRUS INFECTION AFFECTS DNA METHYLATION IN MICE WITH HUMANIZED LIVERS. BACKGROUND & AIMS: CELLS OF TUMORS ASSOCIATED WITH CHRONIC INFLAMMATION FREQUENTLY HAVE ALTERED PATTERNS OF DNA METHYLATION, INCLUDING HEPATOCELLULAR CARCINOMAS. CHRONIC HEPATITIS HAS ALSO BEEN ASSOCIATED WITH ABERRANT DNA METHYLATION, BUT LITTLE IS KNOWN ABOUT THEIR RELATIONSHIP. METHODS: PYROSEQUENCING WAS USED TO DETERMINE THE METHYLATION STATUS OF CULTURED HUH7.5.1 HEPATOMA CELLS AFTER HEPATITIS C VIRUS (HCV) INFECTION. WE ALSO STUDIED MICE WITH SEVERE COMBINED IMMUNODEFICIENCY CARRYING THE UROKINASE-TYPE PLASMINOGEN ACTIVATOR TRANSGENE CONTROLLED BY AN ALBUMIN PROMOTER (UROKINASE-TYPE PLASMINOGEN ACTIVATOR/SEVERE COMBINED IMMUNODEFICIENT MICE), IN WHICH UP TO 85% OF HEPATOCYTES WERE REPLACED BY HUMAN HEPATOCYTES (CHIMERIC MICE). MICE WERE GIVEN INTRAVENOUS INJECTIONS OF HEPATITIS B VIRUS (HBV) OR HCV, LIVER TISSUES WERE COLLECTED, AND DNA METHYLATION PROFILES WERE DETERMINED AT DIFFERENT TIME POINTS AFTER INFECTION. WE ALSO COMPARED METHYLATION PATTERNS BETWEEN PAIRED SAMPLES OF HEPATOCELLULAR CARCINOMAS AND ADJACENT NONTUMOR LIVER TISSUES FROM PATIENTS. RESULTS: NO REPRODUCIBLE CHANGES IN DNA METHYLATION WERE OBSERVED AFTER INFECTION OF HUH7.5.1 CELLS WITH HCV. LIVERS FROM HBV- AND HCV-INFECTED MICE HAD GENOME-WIDE, TIME-DEPENDENT CHANGES IN DNA METHYLATION, COMPARED WITH UNINFECTED UROKINASE-TYPE PLASMINOGEN ACTIVATOR/SEVERE COMBINED IMMUNODEFICIENT MICE. THERE WERE CHANGES IN 160 +/- 63 GENES IN HBV-INFECTED AND 237 +/- 110 GENES IN HCV-INFECTED MICE. METHYLATION OF 149 COMMON GENES INCREASED IN HBV- AND HCV-INFECTED MICE; METHYLATION OF SOME OF THESE GENES ALSO INCREASED IN HEPATOCELLULAR CARCINOMA SAMPLES FROM PATIENTS COMPARED WITH NONTUMOR TISSUES. EXPRESSION OF IFNG, WHICH IS EXPRESSED BY NATURAL KILLER CELLS, INCREASED SIGNIFICANTLY IN CHIMERIC LIVERS, IN CONCORDANCE WITH INDUCTION OF DNA METHYLATION, AFTER INFECTION WITH HBV OR HCV. INDUCTION OF IFNG WAS REDUCED AFTER ADMINISTRATION OF AN INHIBITOR OF NATURAL KILLER CELL FUNCTION (ANTI-ASIALO GM1). CONCLUSIONS: IN CHIMERIC MICE WITH HUMANIZED LIVERS, INFECTION WITH HBV AND HCV APPEARS TO ACTIVATE A NATURAL KILL CELL-DEPENDENT INNATE IMMUNE RESPONSE. THIS CONTRIBUTES TO THE INDUCTION AND ACCUMULATION OF ABERRANT DNA METHYLATION IN HUMAN HEPATOCYTES. 2014 18 2842 43 FREQUENT CONCOMITANT EPIGENETIC SILENCING OF SOX1 AND SECRETED FRIZZLED-RELATED PROTEINS (SFRPS) IN HUMAN HEPATOCELLULAR CARCINOMA. BACKGROUND AND AIM: EXCEPT FOR GENETIC MUTATIONS, EPIGENETIC CHANGES ARE ALSO INVOLVED IN THE DEVELOPMENT OF HUMAN CANCERS. RECENTLY, WE HAVE IDENTIFIED SOX1, SRY (SEX DETERMINING REGION Y)-BOX 1, IS HYPERMETHYLATED IN CERVICAL CANCER AND OVARIAN CANCER. THEREFORE, WE INVESTIGATED WHETHER PROMOTER HYPERMETHYLATION OF SOX1 IS COMMON IN HEPATOCELLULAR CARCINOMA (HCC). METHODS: WE USED METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MS-PCR) AND BISULFITE SEQUENCING TO ANALYZE THE METHYALTION LEVEL OF THE SOX1 PROMOTER IN SEVEN HCC CELL LINES, 54 CLINICAL HCCS, 42 CIRRHOTIC LIVERS, 21 LIVERS WITH CHRONIC HEPATITIS, AND 15 CONTROL LIVERS. THEN, WE EMPLOYED QUANTITATIVE MS-PCR (QMSP) TO VALIDATE IN AN INDEPENDENT SET OF SAMPLES (60 PAIRED HCCS AND 30 CONTROL LIVERS). FINALLY, WE USED LUCIFERASE REPORTER AND COLONY FORMATION ASSAY TO CHECK THE EFFECT OF SOX1 IN HCC. RESULTS: PROMOTER METHYLATION OF SOX1 WAS SIGNIFICANTLY FREQUENT IN HCC CELL LINES AND CLINICAL HCCS, CIRRHOTIC LIVERS, BUT NOT IN CONTROL LIVERS (P < 0.0001). THERE IS A SIGNIFICANT CORRELATION BETWEEN DOWNREGULATION OF SOX1 EXPRESSION AND PROMOTER METHYLATION. QMSP RESULTS CONFIRMED THAT PROMOTER HYPERMETHYLATION OF SOX1 IS SIGNIFICANTLY MORE FREQUENT IN HCCS THAN CONTROL LIVERS (P < 0.0001). THE FREQUENCY OF SOX1 METHYLATION IN PATIENTS WITH SECRETED FRIZZLED-RELATED PROTEINS (SFRPS) METHYLATION IS SIGNIFICANTLY HIGHER THAN IN PATIENTS WITHOUT SFRPS METHYLATION (P < 0.0001). FURTHERMORE, ECTOPIC EXPRESSION OF SOX1 COULD SUPPRESS T-CELL FACTOR-DEPENDENT TRANSCRIPTIONAL ACTIVITY AND COLONY FORMATION NUMBER IN HCCS. CONCLUSIONS: CONCOMITANT EPIGENETIC SILENCING OF SOX1 AND SFRPS THROUGH PROMOTER HYPERMETHYLATION IS FREQUENT IN HCCS, AND THIS MIGHT CONTRIBUTE TO ABNORMAL ACTIVATION OF CANONICAL WNT SIGNAL PATHWAY. 2013 19 6829 44 [HEPATITIS C VIRUS INFECTION AND HEPATOCARCINOGENESIS]. HEPATITIS C VIRUS INFECTION CAUSES APPROXIMATELY 4 MILLION NEW INFECTIONS WORLDWIDE, AND 399 000 DEATHS DUE TO ITS COMPLICATIONS, CIRRHOSIS AND HEPATOCELLULAR CARCINOMA (HCC). MICROENVIRONMENTAL CHANGES, CHRONIC INFLAMMATION, OXIDATIVE STRESS, ENDOPLASMIC RETICULUM STRESS CAUSED BY HCV INFECTION, VIA GENETIC AND EPIGENETIC CHANGES CAN RESULT IN PRIMARY LIVER CANCER DURING DECADES. THE DIRECT ONCOGENIC PROPERTY OF HCV IS WELLKNOWN. THE TRANSFORMING EFFECT OF FOUR HCV PROTEINS (CORE, NS3, NS4B, NS5A) HAS BEEN PROVEN. EFFECTIVE ANTIVIRAL THERAPY, SUSTAINED VIRAL RESPONSE DECREASES THE HCV-RELATED GENERAL AND LIVER-RELATED MORTALITY. INTERFERON-BASED THERAPY REDUCES THE RISK OF HCC DEVELOPMENT. SHORTER THERAPY WITH DIRECT ACTING ANTIVIRAL AGENTS (DAA) HAS HIGHER EFFICACY, FEWER SIDE-EFFECTS. PUBLICATIONS HAVE REPORTED THE UNEXPECTED EFFECTS OF DAA. THE AUTHORS REVIEW THE ARTICLES FOCUSING ON THE OCCURRENCE OF HCC IN CONNECTION WITH DAA THERAPIES. THERE IS A NEED FOR PROSPECTIVE, MULTICENTRIC STUDIES WITH LONGER FOLLOW-UP TO EXAMINE THE RISK OF HCC FORMATION. AFTER ANTIVIRAL THERAPY, HCC SURVEILLANCE IS OF HIGH IMPORTANCE WHICH MEANS ABDOMINAL ULTRASOUND EVERY 3-6-12 MONTHS IN SUSTAINED VIRAL RESPONSE PATIENTS AS WELL. ORV HETIL. 2019; 160(22): 846-853. 2019 20 512 37 ASSOCIATION OF SAT-A AND ALU METHYLATION STATUS WITH HCV-INDUCED CHRONIC LIVER DISEASE AND HEPATOCELLULAR CARCINOMA. BACKGROUND: THE COMBINATION OF EPIGENETIC AND GENETIC ABNORMALITIES CONTRIBUTES TOGETHER TO THE DEVELOPMENT OF LIVER CANCER. THE METHYLATION STATUS OF THE REPETITIVE ELEMENTS (RES) IN DNA HAS BEEN INVESTIGATED IN A VARIETY OF HUMAN ILLNESSES. HOWEVER, THE METHYLATION PATTERNS OF SAT-ALPHA AND ALU RES IN CHRONIC LIVER DISEASE (CLD) AND HEPATOCELLULAR CARCINOMA (HCC) CAUSED BY HEPATITIS C VIRUS (HCV) HAVE NEVER BEEN STUDIED BEFORE. METHODOLOGY: IN THIS STUDY, 3 GROUPS OF PARTICIPANTS INCLUDING 50 PATIENTS HAVING HCV-INDUCED CLD, 50 PATIENTS HAVING HCV-INDUCED HCC, AND 46 HEALTHY SUBJECTS WERE SUBJECTED TO MEASUREMENT OF SAT-ALPHA AND ALU METHYLATION USING THE QUANTITATIVE METHYLIGHT ASSAY. RESULTS: SAT-ALPHA AND ALU METHYLATION PERCENTAGES DECREASED SIGNIFICANTLY IN BOTH CLD AND HCC, COMPARED TO CONTROL. ALSO, A SIGNIFICANT SAT-ALPHA HYPOMETHYLATION WAS DETECTED IN HCC, COMPARED TO CLD. IN ADDITION, SAT-ALPHA AND ALU METHYLATION SHOWED A SIGNIFICANT DECLINE AS LESION SIZE GREW. HOWEVER, ONLY SAT-ALPHA HYPOMETHYLATION WAS SIGNIFICANTLY INCREASED IN ASSOCIATION WITH PORTAL VEIN THROMBOSIS AND THE MELD SCORE. SAT-ALPHA METHYLATION PERCENTAGE HAD THE HIGHEST SENSITIVITY AND SPECIFICITY FOR DIAGNOSING HCC (100% AND 84.4%) FOLLOWED BY ALPHA-FETOPROTEIN (80% AND 84.4%) AND ALU METHYLATION (66% AND 61.5%). FURTHERMORE, THERE WAS A STRONG POSITIVE CORRELATION BETWEEN SAT-ALPHA AND ALU METHYLATION. CONCLUSIONS: MEASURING SAT-ALPHA AND ALU METHYLATION PROVIDES US WITH A NEW TOOL FOR EARLY DETECTING HCV-INDUCED CLD AND HEPATOCARCINOGENESIS. SAT-ALPHA HAS THE POTENTIAL TO BE UTILIZED AS AN INDEPENDENT PREDICTIVE PARAMETER FOR HCC DEVELOPMENT AND PROGRESSION BECAUSE OF ITS ABILITY TO DISTINGUISH BETWEEN CLD AND HCC WITH THEIR DIFFERENT MELD SCORES. 2022