1 261 161 ADVANCES IN TARGET THERAPY FOR LUNG CANCER. RECENT PROGRESS IN MOLECULAR BIOLOGY HAS SHOWN THAT CANCER CELLS ACQUIRE COMMON PHENOTYPES SUCH AS SELF-SUFFICIENCY OF GROWTH SIGNALS, RESISTANCE TO ANTI-PROLIFERATIVE AND APOPTOTIC SIGNALS THROUGH THE ACCUMULATION OF GENETIC AND EPIGENETIC CHANGES. RECENTLY DEVELOPED ANTICANCER DRUGS TARGET THESE MOLECULAR MECHANISMS AND GOOD RESULTS HAVE BEEN REPORTED FOR VARIOUS CANCER TYPES. IN LUNG CANCER, TYROSINE KINASE INHIBITORS SPECIFIC FOR THE EPIDERMAL GROWTH FACTOR RECEPTOR SUCH AS GEFITINIB AND ERLOTINIB HAVE CHANGED CLINICAL PRACTICE DRAMATICALLY. ABOUT HALF OF THE JAPANESE PATIENTS WITH LUNG CANCERS HARBOR AN ACTIVATING MUTATION OF THE EPIDERMAL GROWTH FACTOR RECEPTOR GENE AND THEY ARE VERY SENSITIVE TO EPIDERMAL GROWTH FACTOR RECEPTOR TYROSINE KINASE INHIBITORS. PROGRESSION-FREE SURVIVAL OF SUCH PATIENTS IS APPROXIMATELY 10 MONTHS WHEN TREATED WITH GEFITINIB, WHEREAS THE SURVIVAL FOR THOSE TREATED WITH PLATINUM DOUBLET THERAPY IS APPROXIMATELY 6 MONTHS. TARGET THERAPIES AGAINST ECHINODERM MICROTUBULE-ASSOCIATED PROTEIN-LIKE 4-ANAPLASTIC LYMPHOMA KINASE FUSION PROTEIN OR A MUTATED ERBB2 (V-ERB-B AVIAN ERYTHROBLASTIC LEUKEMIA VIRAL ONCOGENE HOMOLOGUE 2) PRESENT IN APPROXIMATELY 5% AND APPROXIMATELY 3% OF THE JAPANESE PATIENTS WITH ADENOCARCINOMAS, RESPECTIVELY, ARE CURRENTLY UNDER DEVELOPMENT. ADDITION OF AN ANTI-EPIDERMAL GROWTH FACTOR RECEPTOR ANTIBODY, CETUXIMAB, OR ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR ANTIBODY, BEVACIZUMAB, TO PLATINUM DOUBLET THERAPY SIGNIFICANTLY BUT MODESTLY PROLONGED THE SURVIVAL IN RECENT CLINICAL TRIALS. HOWEVER, CLINICAL DEVELOPMENT OF SMALL MOLECULE MULTI-KINASE INHIBITORS INCLUDING THOSE TARGETING VASCULAR ENDOTHELIAL GROWTH FACTOR RECEPTORS, SUCH AS VANDETANIB, SUNITINIB AND SORAFENIB, HAS NOT BEEN VERY SUCCESSFUL. THROUGH THESE COLLABORATIONS AMONG CLINICIANS, BASIC RESEARCHERS AND PHARMACEUTICAL COMPANIES, IT SHOULD BE POSSIBLE TO INDIVIDUALIZE LUNG CANCER TREATMENT TO TURN THIS FATAL DISEASE INTO A CHRONIC DISORDER AND, EVENTUALLY, TO CURE IT. 2010 2 3260 39 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 3 5521 32 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 4 3190 34 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 5 3271 33 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 6 1042 30 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 7 442 29 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 8 5486 41 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 9 3780 33 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 10 5365 28 RECENT ADVANCES IN HEPATITIS B TREATMENT. HEPATITIS B VIRUS INFECTION AFFECTS OVER 250 MILLION CHRONIC CARRIERS, CAUSING MORE THAN 800,000 DEATHS ANNUALLY, ALTHOUGH A SAFE AND EFFECTIVE VACCINE IS AVAILABLE. CURRENTLY USED ANTIVIRAL AGENTS, PEGYLATED INTERFERON AND NUCLEOS(T)IDE ANALOGUES, HAVE MAJOR DRAWBACKS AND FAIL TO COMPLETELY ERADICATE THE VIRUS FROM INFECTED CELLS. THUS, ACHIEVING A "FUNCTIONAL CURE" OF THE INFECTION REMAINS A REAL CHALLENGE. RECENT FINDINGS CONCERNING THE VIRAL REPLICATION CYCLE HAVE LED TO DEVELOPMENT OF NOVEL THERAPEUTIC APPROACHES INCLUDING VIRAL ENTRY INHIBITORS, EPIGENETIC CONTROL OF CCCDNA, IMMUNE MODULATORS, RNA INTERFERENCE TECHNIQUES, RIBONUCLEASE H INHIBITORS, AND CAPSID ASSEMBLY MODULATORS. PROMISING PRECLINICAL RESULTS HAVE BEEN OBTAINED, AND THE LEADING MOLECULES UNDER DEVELOPMENT HAVE ENTERED CLINICAL EVALUATION. THIS REVIEW SUMMARIZES THE KEY STEPS OF THE HBV LIFE CYCLE, EXAMINES THE CURRENTLY APPROVED ANTI-HBV DRUGS, AND ANALYZES NOVEL HBV TREATMENT REGIMENS. 2021 11 3259 27 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 12 2915 37 GENE THERAPY FOR CHRONIC HBV-CAN WE ELIMINATE CCCDNA? CHRONIC INFECTION WITH THE HEPATITIS B VIRUS (HBV) IS A GLOBAL HEALTH CONCERN AND ACCOUNTS FOR APPROXIMATELY 1 MILLION DEATHS ANNUALLY. AMONGST OTHER LIMITATIONS OF CURRENT ANTI-HBV TREATMENT, FAILURE TO ELIMINATE THE VIRAL COVALENTLY CLOSED CIRCULAR DNA (CCCDNA) AND EMERGENCE OF RESISTANCE REMAIN THE MOST WORRISOME. VIRAL REBOUND FROM LATENT EPISOMAL CCCDNA RESERVOIRS OCCURS FOLLOWING CESSATION OF THERAPY, PATIENT NON-COMPLIANCE, OR THE DEVELOPMENT OF ESCAPE MUTANTS. SIMULTANEOUS VIRAL CO-INFECTIONS, SUCH AS BY HIV-1, FURTHER COMPLICATE THERAPEUTIC INTERVENTIONS. THESE CHALLENGES HAVE PROMPTED DEVELOPMENT OF NOVEL TARGETED HEPATITIS B THERAPIES. GIVEN THE EASE WITH WHICH HIGHLY SPECIFIC AND POTENT NUCLEIC ACID THERAPEUTICS CAN BE RATIONALLY DESIGNED, GENE THERAPY HAS GENERATED INTEREST FOR ANTIVIRAL APPLICATION. GENE THERAPY STRATEGIES DEVELOPED FOR HBV INCLUDE GENE SILENCING BY HARNESSING RNA INTERFERENCE, TRANSCRIPTIONAL INHIBITION THROUGH EPIGENETIC MODIFICATION OF TARGET DNA, GENOME EDITING BY DESIGNER NUCLEASES, AND IMMUNE MODULATION WITH CYTOKINES. DNA-BINDING DOMAINS AND EFFECTORS BASED ON THE ZINC FINGER (ZF), TRANSCRIPTION ACTIVATOR-LIKE EFFECTOR (TALE), AND CLUSTERED REGULARLY INTERSPACED SHORT PALINDROMIC REPEAT (CRISPR) SYSTEMS ARE REMARKABLY WELL SUITED TO TARGETING EPISOMAL CCCDNA. THIS REVIEW DISCUSSES RECENT DEVELOPMENTS AND CHALLENGES FACING THE FIELD OF ANTI-HBV GENE THERAPY, ITS POTENTIAL CURATIVE SIGNIFICANCE AND THE PROGRESS TOWARDS CLINICAL APPLICATION. 2018 13 791 36 CELLULAR AND MOLECULAR NETWORKS IN CHRONIC MYELOID LEUKEMIA: THE LEUKEMIC STEM, PROGENITOR AND STROMAL CELL INTERPLAY. THE USE OF IMATINIB, SECOND AND THIRD GENERATION ABL TYROSINE KINASE INHIBITORS (TKI) (I.E. DASATINIB, NILOTINIB, BOSUTINIB AND PONATINIB) MADE CML A CLINICALLY MANAGEABLE AND, IN A SMALL PERCENTAGE OF CASES, A CURED DISEASE. TKI THERAPY ALSO TURNED CML BLASTIC TRANSFORMATION INTO A RARE EVENT; HOWEVER, DISEASE PROGRESSION STILL OCCURS IN THOSE PATIENTS WHO ARE REFRACTORY, NOT COMPLIANT WITH TKI THERAPY OR DEVELOP RESISTANCE TO MULTIPLE TKIS. IN THE PAST FEW YEARS, IT BECAME CLEAR THAT THE BCRABL1 ONCOGENE DOES NOT OPERATE ALONE TO DRIVE DISEASE EMERGENCE, MAINTENANCE AND PROGRESSION. INDEED, IT SEEMS THAT BONE MARROW (BM) MICROENVIRONMENT-GENERATED SIGNALS AND CELL AUTONOMOUS BCRABL1 KINASE-INDEPENDENT GENETIC AND EPIGENETIC ALTERATIONS ALL CONTRIBUTE TO: I. PERSISTENCE OF A QUIESCENT LEUKEMIC STEM CELL (LSC) RESERVOIR, II. INNATE OR ACQUIRED RESISTANCE TO TKIS, AND III. PROGRESSION INTO THE FATAL BLAST CRISIS STAGE. HEREIN, WE REVIEW THE INTRICATE LEUKEMIC NETWORK IN WHICH ABERRANT, BUT FINELY TUNED, SURVIVAL, MITOGENIC AND SELF-RENEWAL SIGNALS ARE GENERATED BY LEUKEMIC PROGENITORS, STROMAL CELLS, IMMUNE CELLS AND METABOLIC MICROENVIRONMENTAL CONDITIONS (E.G. HYPOXIA) TO PROMOTE LSC MAINTENANCE AND BLASTIC TRANSFORMATION. 2017 14 4815 37 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 15 4055 33 MAPPING OF HISTONE MODIFICATIONS IN EPISOMAL HBV CCCDNA UNCOVERS AN UNUSUAL CHROMATIN ORGANIZATION AMENABLE TO EPIGENETIC MANIPULATION. CHRONIC HEPATITIS B VIRUS (HBV) INFECTION AFFECTS 240 MILLION PEOPLE WORLDWIDE AND IS A MAJOR RISK FACTOR FOR LIVER FAILURE AND HEPATOCELLULAR CARCINOMA. CURRENT ANTIVIRAL THERAPY INHIBITS CYTOPLASMIC HBV GENOMIC REPLICATION, BUT IS NOT CURATIVE BECAUSE IT DOES NOT DIRECTLY AFFECT NUCLEAR HBV CLOSED CIRCULAR DNA (CCCDNA), THE GENOMIC FORM THAT TEMPLATES VIRAL TRANSCRIPTION AND SUSTAINS VIRAL PERSISTENCE. NOVEL APPROACHES THAT DIRECTLY TARGET CCCDNA REGULATION WOULD THEREFORE BE HIGHLY DESIRABLE. CCCDNA IS ASSEMBLED WITH CELLULAR HISTONE PROTEINS INTO CHROMATIN, BUT LITTLE IS KNOWN ABOUT THE REGULATION OF HBV CHROMATIN BY HISTONE POSTTRANSLATIONAL MODIFICATIONS (PTMS). HERE, USING A NEW CCCDNA CHIP-SEQ APPROACH, WE REPORT, TO OUR KNOWLEDGE, THE FIRST GENOME-WIDE MAPS OF PTMS IN CCCDNA-CONTAINING CHROMATIN FROM DE NOVO INFECTED HEPG2 CELLS, PRIMARY HUMAN HEPATOCYTES, AND FROM HBV-INFECTED LIVER TISSUE. WE FIND HIGH LEVELS OF PTMS ASSOCIATED WITH ACTIVE TRANSCRIPTION ENRICHED AT SPECIFIC SITES WITHIN THE HBV GENOME AND, SURPRISINGLY, VERY LOW LEVELS OF PTMS LINKED TO TRANSCRIPTIONAL REPRESSION EVEN AT SILENT HBV PROMOTERS. WE SHOW THAT TRANSCRIPTION AND ACTIVE PTMS IN HBV CHROMATIN ARE REDUCED BY THE ACTIVATION OF AN INNATE IMMUNITY PATHWAY, AND THAT THIS EFFECT CAN BE RECAPITULATED WITH A SMALL MOLECULE EPIGENETIC MODIFYING AGENT, OPENING THE POSSIBILITY THAT CHROMATIN-BASED REGULATION OF CCCDNA TRANSCRIPTION COULD BE A NEW THERAPEUTIC APPROACH TO CHRONIC HBV INFECTION. 2015 16 6640 34 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 17 6857 47 [NOVEL CONVENTIONAL THERAPIES IN ONCO-HEMATHOLOGY]. CYTOGENETIC, MOLECULAR AND PHENOTYPING FEATURES OF MALIGNANT HEMATOLOGIC DISEASES SUCCEEDED IN IMPROVING THEIR MANAGEMENT BY A MORE ACCURATE STRATIFICATION OF PATIENTS ACCORDING TO SEVERAL GROUPS OF RISK AND BY PROVIDING A RATIONAL FOR TARGETED THERAPY. THREE MAJOR TYPES OF TREATMENT (EXCLUDING CELLULAR THERAPY) ARE CURRENTLY AVAILABLE IN ONCO-HEMATOLOGY: CONVENTIONAL CHEMOTHERAPY, SMALL MOLECULES FOR TARGETED THERAPY AND MONOCLONAL ANTIBODIES. CONVENTIONAL CHEMOTHERAPY WITH OPTIMIZATION OF DOSES AND MULTIDRUG-BASED REGIMENS ALLOWED TO SUBSTANTIALLY IMPROVE SURVIVAL OF PATIENTS AND KEEPS A PLACE OF CHOICE IN TREATMENT OF THESE DISEASES. TARGETED TREATMENTS CAME FROM THE CYTOGENETIC AND MOLECULAR CHARACTERIZATION OF HEMOPATHIES. THUS, THE KINASE BCR-ABL, AS A RESULT OF THE TRANSLOCATION T(9;22)(Q34;Q11), HAS BEEN SUCCESSFULLY TARGETED BY TYROSINE KINASE INHIBITORS (TKI) IN CHRONIC MYELOID LEUKEMIA AND PH+ ACUTE LYMPHOBLASTIC LEUKEMIA. MOLECULAR ABNORMALITIES LIKE INTERNAL-TANDEM DUPLICATION/POINT ACTIVATING MUTATIONS IN FLT3 IN SOME ACUTE MYELOBLASTIC LEUKEMIA OR EPIGENETIC DYSREGULATIONS IN SOME BLOOD MALIGNANCIES CAN ALSO BE TARGETED BY SMALL MOLECULES. HEMATOPOIETIC MALIGNANT CELLS ARE PHENOTYPICALLY CHARACTERIZED BY EXPRESSION OF CLUSTER OF DIFFERENTIATION (CD) ON THEIR SURFACE. THESE CD ARE DETECTED BY FLOW CYTOMETRY USING SPECIFIC ANTIBODIES. MONOCLONAL ANTIBODIES TARGETING DIFFERENT CD HAVE BEEN DEVELOPED FOR TREATMENT. RITUXIMAB, AN ANTI-CD20 ANTIBODY, WAS THE FIRST MONOCLONAL ANTIBODY SUCCESSFULLY DEVELOPED FOR TREATMENT OF MALIGNANT HEMATOLOGIC DISEASES. SINCE RITUXIMAB, MANY OTHER MONOCLONAL ANTIBODIES ARE BEING DEVELOPED. TRENDS IN MALIGNANT HEMATOLOGIC DISEASES PRESENTED HERE WILL INCLUDE TREATMENTS, WHICH HAVE AT LEAST ENTERED PHASE I/II CLINICAL TRIALS IN ADULT OR CHILDHOOD LEUKEMIA. THEY INCLUDE SOME NOVEL DRUGS OF CONVENTIONAL CHEMOTHERAPY LIKE SECOND-GENERATION NUCLEOSIDE ANALOGUES. WE WILL GIVE AN OVERVIEW OF THE SMALL MOLECULES TARGETING THE DIFFERENT CELLULAR PATHWAYS AND WE WILL HIGHLIGHT THOSE APPEARING AS THE MOST PROMISING LIKE NOVEL TKIS. THE LARGE FIELD OF MONOCLONAL ANTIBODIES WILL BE ALSO APPROACHED FOCUSING ON ANTIBODIES DEVELOPED IN LEUKEMIAS. 2011 18 3394 29 HOST EPIGENETIC ALTERATIONS AND HEPATITIS B VIRUS-ASSOCIATED HEPATOCELLULAR CARCINOMA. HEPATOCELLULAR CARCINOMA (HCC) IS THE MOST FREQUENT PRIMARY MALIGNANCY OF THE LIVER AND A LEADING CAUSE OF CANCER-RELATED DEATHS WORLDWIDE. ALTHOUGH MUCH PROGRESS HAS BEEN MADE IN HCC DRUG DEVELOPMENT IN RECENT YEARS, TREATMENT OPTIONS REMAIN LIMITED. THE MAJOR CAUSE OF HCC IS CHRONIC HEPATITIS B VIRUS (HBV) INFECTION. DESPITE THE EXISTENCE OF A VACCINE, MORE THAN 250 MILLION INDIVIDUALS ARE CHRONICALLY INFECTED BY HBV. CURRENT ANTIVIRAL THERAPIES CAN REPRESS VIRAL REPLICATION BUT TO DATE THERE IS NO CURE FOR CHRONIC HEPATITIS B. OF NOTE, INHIBITION OF VIRAL REPLICATION REDUCES BUT DOES NOT ELIMINATE THE RISK OF HCC DEVELOPMENT. HBV CONTRIBUTES TO LIVER CARCINOGENESIS BY DIRECT AND INDIRECT EFFECTS. THIS REVIEW SUMMARIZES THE CURRENT KNOWLEDGE OF HBV-INDUCED HOST EPIGENETIC ALTERATIONS AND THEIR ASSOCIATION WITH HCC, WITH AN EMPHASIS ON THE INTERACTIONS BETWEEN HBV PROTEINS AND THE HOST CELL EPIGENETIC MACHINERY LEADING TO MODULATION OF GENE EXPRESSION. 2021 19 5952 39 TARGETING VIRAL CCCDNA FOR CURE OF CHRONIC HEPATITIS B. PURPOSE OF REVIEW: CHRONIC HEPATITIS B (CHB), CAUSED BY HEPATITIS B VIRUS (HBV), IS A MAJOR CAUSE OF ADVANCED LIVER DISEASE AND HEPATOCELLULAR CARCINOMA (HCC) WORLDWIDE. HBV REPLICATION IS CHARACTERIZED BY THE SYNTHESIS OF COVALENTLY CLOSED CIRCULAR (CCC) DNA WHICH IS NOT TARGETED BY ANTIVIRAL NUCLEOS(T)IDE ANALOGUES (NUCS) THE KEY MODALITY OF STANDARD OF CARE. WHILE HBV REPLICATION IS SUCCESSFULLY SUPPRESSED IN TREATED PATIENTS, THEY REMAIN AT RISK FOR DEVELOPING HCC. WHILE FUNCTIONAL CURE, CHARACTERIZED BY LOSS OF HBSAG, IS THE FIRST GOAL OF NOVEL ANTIVIRAL THERAPIES, CURATIVE TREATMENTS ELIMINATING CCCDNA REMAIN THE ULTIMATE GOAL. THIS REVIEW SUMMARIZES RECENT ADVANCES IN THE DISCOVERY AND DEVELOPMENT OF NOVEL THERAPEUTIC STRATEGIES AND THEIR IMPACT ON CCCDNA BIOLOGY. RECENT FINDINGS: WITHIN THE LAST DECADE, SUBSTANTIAL PROGRESS HAS BEEN MADE IN THE UNDERSTANDING OF CCCDNA BIOLOGY INCLUDING THE DISCOVERY OF HOST DEPENDENCY FACTORS, EPIGENETIC REGULATION OF CCCDNA TRANSCRIPTION AND IMMUNE-MEDIATED DEGRADATION. SEVERAL APPROACHES TARGETING CCCDNA EITHER IN A DIRECT OR INDIRECT MANNER ARE CURRENTLY AT THE STAGE OF DISCOVERY, PRECLINICAL OR EARLY CLINICAL DEVELOPMENT. EXAMPLES INCLUDE GENOME-EDITING APPROACHES, STRATEGIES TARGETING HOST DEPENDENCY FACTORS OR EPIGENETIC GENE REGULATION, NUCLEOCAPSID MODULATORS AND IMMUNE-MEDIATED DEGRADATION. SUMMARY: WHILE DIRECT-TARGETING CCCDNA STRATEGIES ARE STILL LARGELY AT THE PRECLINICAL STAGE OF DEVELOPMENT, CAPSID ASSEMBLY MODULATORS AND IMMUNE-BASED APPROACHES HAVE REACHED THE CLINICAL PHASE. CLINICAL TRIALS ARE ONGOING TO ASSESS THEIR EFFICACY AND SAFETY IN PATIENTS INCLUDING THEIR IMPACT ON VIRAL CCCDNA. COMBINATION THERAPIES PROVIDE ADDITIONAL OPPORTUNITIES TO OVERCOME CURRENT LIMITATIONS OF INDIVIDUAL APPROACHES. 2020 20 5731 28 SMAD3 PHOSPHO-ISOFORM SIGNALING IN HEPATITIS C VIRUS-RELATED CHRONIC LIVER DISEASES. THE RISK OF HEPATOCELLULAR CARCINOMA (HCC) DEVELOPMENT INCREASES AS HEPATITIS VIRUS C (HCV)-RELATED LIVER DISEASES PROGRESS, ESPECIALLY IN PATIENTS WITH ACTIVE INFLAMMATION. INSIGHT INTO HEPATIC CARCINOGENESIS HAVE EMERGED FROM RECENT DETAILED ANALYSES OF TRANSFORMING GROWTH FACTOR-BETA AND C-JUN-N-TERMINAL KINASE SIGNALING PROCESSES DIRECTED BY MULTIPLE PHOSPHORYLATED (PHOSPHO)-ISOFORMS OF A SMAD3 MEDIATOR. IN THE COURSE OF HCV-RELATED CHRONIC LIVER DISEASES, CHRONIC INFLAMMATION AND HOST GENETIC/EPIGENETIC ALTERATIONS ADDITIVELY SHIFT THE HEPATOCYTIC SMAD3 PHOSPHO-ISOFORM SIGNALING FROM TUMOR SUPPRESSION TO CARCINOGENESIS, INCREASING THE RISK OF HCC. CHRONIC INFLAMMATION REPRESENTS AN EARLY CARCINOGENIC STEP THAT PROVIDES A NONMUTAGENIC TUMOR-PROMOTING STIMULUS. AFTER UNDERGOING SUCCESSFUL ANTIVIRAL THERAPY, PATIENTS WITH CHRONIC HEPATITIS C COULD EXPERIENCE A LOWER RISK OF HCC AS SMAD3 PHOSPHO-ISOFORM SIGNALING REVERSES FROM POTENTIAL CARCINOGENESIS TO TUMOR SUPPRESSION. EVEN AFTER HCV CLEARANCE, HOWEVER, PATIENTS WITH CIRRHOSIS COULD STILL DEVELOP HCC BECAUSE OF SUSTAINED, INTENSE CARCINOGENIC SMAD3 PHOSPHO-ISOFORM SIGNALING THAT IS POSSIBLY CAUSED BY GENETIC OR EPIGENETIC ALTERATIONS. SMAD3 PHOSPHO-ISOFORMS SHOULD ASSIST WITH EVALUATING THE EFFECTIVENESS OF INTERVENTIONS AIMED AT REDUCING HUMAN HCC. 2014