1 3605 167 IMPROVING PARP INHIBITOR EFFICACY IN HIGH-GRADE SEROUS OVARIAN CARCINOMA: A FOCUS ON THE IMMUNE SYSTEM. HIGH-GRADE SEROUS OVARIAN CARCINOMA (HGSOC) IS A GENOMICALLY UNSTABLE MALIGNANCY RESPONSIBLE FOR OVER 70% OF ALL DEATHS DUE TO OVARIAN CANCER. WITH ROUGHLY 50% OF ALL HGSOC HARBORING DEFECTS IN THE HOMOLOGOUS RECOMBINATION (HR) DNA REPAIR PATHWAY (E.G., BRCA1/2 MUTATIONS), THE INTRODUCTION OF POLY ADP-RIBOSE POLYMERASE INHIBITORS (PARPI) HAS DRAMATICALLY IMPROVED OUTCOMES FOR WOMEN WITH HR DEFECTIVE HGSOC. BY BLOCKING THE REPAIR OF SINGLE-STRANDED DNA DAMAGE IN CANCER CELLS ALREADY LACKING HIGH-FIDELITY HR PATHWAYS, PARPI CAUSES THE ACCUMULATION OF DOUBLE-STRANDED DNA BREAKS, LEADING TO CELL DEATH. THUS, THIS SYNTHETIC LETHALITY RESULTS IN PARPI SELECTIVELY TARGETING CANCER CELLS, RESULTING IN IMPRESSIVE EFFICACY. DESPITE THIS, RESISTANCE TO PARPI COMMONLY DEVELOPS THROUGH DIVERSE MECHANISMS, SUCH AS THE ACQUISITION OF SECONDARY BRCA1/2 MUTATIONS. PERHAPS LESS WELL DOCUMENTED IS THAT PARPI CAN IMPACT BOTH THE TUMOUR MICROENVIRONMENT AND THE IMMUNE RESPONSE, THROUGH UPREGULATION OF THE STIMULATOR OF INTERFERON GENES (STING) PATHWAY, UPREGULATION OF IMMUNE CHECKPOINTS SUCH AS PD-L1, AND BY STIMULATING THE PRODUCTION OF PRO-INFLAMMATORY CYTOKINES. WHILST TARGETED IMMUNOTHERAPIES HAVE NOT YET FOUND THEIR PLACE IN THE CLINIC FOR HGSOC, THE EVIDENCE ABOVE, AS WELL AS ONGOING STUDIES EXPLORING THE SYNERGISTIC EFFECTS OF PARPI WITH IMMUNE AGENTS, INCLUDING IMMUNE CHECKPOINT INHIBITORS, SUGGESTS POTENTIAL FOR TARGETING THE IMMUNE RESPONSE IN HGSOC. ADDITIONALLY, COMBINING PARPI WITH EPIGENETIC-MODULATING DRUGS MAY IMPROVE PARPI EFFICACY, BY INDUCING A BRCA-DEFECTIVE PHENOTYPE TO SENSITISE RESISTANT CANCER CELLS TO PARPI. FINALLY, INVIGORATING AN IMMUNE RESPONSE DURING PARPI THERAPY MAY ENGAGE ANTI-CANCER IMMUNE RESPONSES THAT POTENTIATE EFFICACY AND MITIGATE THE DEVELOPMENT OF PARPI RESISTANCE. HERE, WE WILL REVIEW THE EMERGING PARPI LITERATURE WITH A FOCUS ON PARPI EFFECTS ON THE IMMUNE RESPONSE IN HGSOC, AS WELL AS THE POTENTIAL OF EPIGENETIC COMBINATION THERAPIES. WE HIGHLIGHT THE POTENTIAL OF TRANSFORMING HGSOC FROM A LETHAL TO A CHRONIC DISEASE AND INCREASING THE LIKELIHOOD OF CURE. 2022 2 6584 29 TRIGGERING RECEPTORS EXPRESSED ON MYELOID CELLS 1 : OUR NEW PARTNER IN HUMAN ONCOLOGY? INFLAMMATION IS RECOGNIZED AS ONE OF THE HALLMARKS OF CANCER. INDEED, STRONG EVIDENCE INDICATES THAT CHRONIC INFLAMMATION PLAYS A MAJOR ROLE IN ONCOGENESIS, PROMOTING GENOME INSTABILITY, EPIGENETIC ALTERATIONS, PROLIFERATION AND DISSEMINATION OF CANCER CELLS. MONONUCLEAR PHAGOCYTES (MPS) HAVE BEEN IDENTIFIED AS KEY CONTRIBUTORS OF THE INFLAMMATORY INFILTRATE IN SEVERAL SOLID HUMAN NEOPLASIA, PROMOTING ANGIOGENESIS AND CANCER PROGRESSION. ONE OF THE MOST DESCRIBED AMPLIFIERS OF MPS PRO-INFLAMMATORY INNATE IMMUNE RESPONSE IS THE TRIGGERING RECEPTORS EXPRESSED ON MYELOID CELLS 1 (TREM-1). GROWING EVIDENCE SUGGESTS TREM-1 INVOLVEMENT IN ONCOGENESIS THROUGH CANCER RELATED INFLAMMATION AND THE SURROUNDING TUMOR MICROENVIRONMENT. IN HUMAN ONCOLOGY, HIGH LEVELS OF TREM-1 AND/OR ITS SOLUBLE FORM HAVE BEEN ASSOCIATED WITH POORER SURVIVAL DATA IN SEVERAL SOLID MALIGNANCIES, ESPECIALLY IN HEPATOCELLULAR CARCINOMA AND LUNG CANCER. TREM-1 SHOULD BE CONSIDERED AS A POTENTIAL BIOMARKER IN HUMAN ONCOLOGY AND COULD BE USED AS A NEW THERAPEUTIC TARGET OF INTEREST IN HUMAN ONCOLOGY (TREM-1 INHIBITORS, TREM-1 AGONISTS). MORE CLINICAL STUDIES ARE URGENTLY NEEDED TO CONFIRM TREM-1 (AND TREM FAMILY) ROLES IN THE PROGNOSIS AND THE TREATMENT OF HUMAN SOLID CANCERS. 2022 3 5153 28 PPP2R2B HYPERMETHYLATION CAUSES ACQUIRED APOPTOSIS DEFICIENCY IN SYSTEMIC AUTOIMMUNE DISEASES. CHRONIC INFLAMMATION CAUSES TARGET ORGAN DAMAGE IN PATIENTS WITH SYSTEMIC AUTOIMMUNE DISEASES. THE FACTORS THAT ALLOW THIS PROTRACTED RESPONSE ARE POORLY UNDERSTOOD. WE ANALYZED THE TRANSCRIPTIONAL REGULATION OF PPP2R2B (B55SS), A MOLECULE NECESSARY FOR THE TERMINATION OF THE IMMUNE RESPONSE, IN PATIENTS WITH AUTOIMMUNE DISEASES. ALTERED EXPRESSION OF B55SS CONDITIONED RESISTANCE TO CYTOKINE WITHDRAWAL-INDUCED DEATH (CWID) IN PATIENTS WITH AUTOIMMUNE DISEASES. THE IMPAIRED UPREGULATION OF B55SS WAS CAUSED BY INFLAMMATION-DRIVEN HYPERMETHYLATION OF SPECIFIC CYTOSINES LOCATED WITHIN A REGULATORY ELEMENT OF PPP2R2B PREVENTING CTCF BINDING. THIS PHENOTYPE COULD BE INDUCED IN HEALTHY T CELLS BY EXPOSURE TO TNF-ALPHA. OUR RESULTS REVEAL A GENE WHOSE EXPRESSION IS AFFECTED BY AN ACQUIRED DEFECT, THROUGH AN EPIGENETIC MECHANISM, IN THE SETTING OF SYSTEMIC AUTOIMMUNITY. BECAUSE FAILURE TO REMOVE ACTIVATED T CELLS THROUGH CWID COULD CONTRIBUTE TO AUTOIMMUNE PATHOLOGY, THIS MECHANISM ILLUSTRATES A VICIOUS CYCLE THROUGH WHICH AUTOIMMUNE INFLAMMATION CONTRIBUTES TO ITS OWN PERPETUATION. 2019 4 5433 27 REL/NF-KAPPA B/I KAPPA B SIGNAL TRANSDUCTION IN THE GENERATION AND TREATMENT OF HUMAN CANCER. THE REL/NF-KAPPA B FAMILY IS A GROUP OF STRUCTURALLY-RELATED, TIGHTLY-REGULATED TRANSCRIPTION FACTORS THAT CONTROL THE EXPRESSION OF A MULTITUDE OF GENES INVOLVED IN KEY CELLULAR AND ORGANISMAL PROCESSES. THE REL/NF-KAPPA B SIGNAL TRANSDUCTION PATHWAY IS MISREGULATED IN A VARIETY OF HUMAN CANCERS, ESPECIALLY ONES OF LYMPHOID CELL ORIGIN, DUE EITHER TO GENETIC CHANGES (SUCH AS CHROMOSOMAL REARRANGEMENTS, AMPLIFICATIONS, AND MUTATIONS) OR TO CHRONIC ACTIVATION OF THE PATHWAY BY EPIGENETIC MECHANISMS. CONSTITUTIVE ACTIVATION OF THE REL/NF-KAPPA B PATHWAY CAN CONTRIBUTE TO THE ONCOGENIC STATE IN SEVERAL WAYS, FOR EXAMPLE, BY DRIVING PROLIFERATION, BY ENHANCING CELL SURVIVAL, OR BY PROMOTING ANGIOGENESIS OR METASTASIS. IN MANY CASES, INHIBITION OF REL/NF-KAPPA B ACTIVITY REVERSES ALL OR PART OF THE MALIGNANT STATE. THUS, THE REL/NF-KAPPA B PATHWAY HAS RECEIVED MUCH ATTENTION AS A FOCAL POINT FOR CLINICAL INTERVENTION. 2002 5 4545 38 MUTANT P53 GAIN OF FUNCTION AND CHEMORESISTANCE: THE ROLE OF MUTANT P53 IN RESPONSE TO CLINICAL CHEMOTHERAPY. PURPOSE: TO REVIEW MECHANISMS UNDERLYING MUTANT P53 (MUTP53) GAIN OF FUNCTION (GOF) AND MUTP53-INDUCED CHEMORESISTANCE, AND TO INVESTIGATE THE ROLE OF MUTP53 IN RESPONSE TO CLINICAL CHEMOTHERAPY. METHODS: WE SEARCHED THE PUBMED DATABASE FOR CLINICAL STUDIES FROM THE PAST DECADE, INCLUDING DATA EVALUATING THE IMPACT OF MUTP53 IN CLINICAL CHEMOTHERAPY RESPONSE. RESULTS: INTERACTIONS BETWEEN MUTP53 AND TRANSCRIPTIONAL FACTORS, PROTEINS OR DNA STRUCTURES, AS WELL AS EPIGENETIC REGULATION, CONTRIBUTE TO MUTP53 GOF. MAJOR MECHANISMS OF MUTP53-INDUCED CHEMORESISTANCE INCLUDE ENHANCED DRUG EFFLUX AND METABOLISM, PROMOTING SURVIVAL, INHIBITING APOPTOSIS, UPREGULATING DNA REPAIR, SUPPRESSING AUTOPHAGY, ELEVATING MICROENVIRONMENTAL RESISTANCE AND INDUCING A STEM-LIKE PHENOTYPE. CLINICALLY, MUTP53 PREDICTED RESISTANCE TO CHEMOTHERAPY IN DIFFUSE LARGE B-CELL LYMPHOMA, AND ESOPHAGEAL AND OROPHARYNGEAL CANCERS, BUT ITS IMPACT ON CHRONIC LYMPHOCYTIC LEUKEMIA WAS UNCLEAR. IN BLADDER CANCER, MUTP53 DID NOT PREDICT RESISTANCE, WHEREAS IN SOME BREAST AND OVARIAN CANCERS, IT WAS ASSOCIATED WITH SENSITIVITY TO CERTAIN CHEMOTHERAPEUTIC AGENTS. CONCLUSION: MUTP53 HAS AN INTRICATE ROLE IN THE RESPONSE TO CLINICAL CHEMOTHERAPY AND SHOULD NOT BE INTERPRETED IN ISOLATION. FURTHERMORE, WHEN PREDICTING TUMOR RESPONSE TO CHEMOTHERAPY BASED ON THE P53 STATUS, THE DRUGS USED SHOULD ALSO BE TAKEN INTO CONSIDERATION. THESE CONCEPTS REQUIRE FURTHER INVESTIGATION. 2017 6 3143 41 GLOBAL MIRNA/PROTEOMIC ANALYSES IDENTIFY MIRNAS AT 14Q32 AND 3P21, WHICH CONTRIBUTE TO FEATURES OF CHRONIC IRON-EXPOSED FALLOPIAN TUBE EPITHELIAL CELLS. MALIGNANT TRANSFORMATION OF FALLOPIAN TUBE SECRETORY EPITHELIAL CELLS (FTSECS) IS A KEY CONTRIBUTING EVENT TO THE DEVELOPMENT OF HIGH-GRADE SEROUS OVARIAN CARCINOMA (HGSOC). OUR RECENT FINDINGS IMPLICATE ONCOGENIC TRANSFORMATIVE EVENTS IN CHRONIC IRON-EXPOSED FTSECS, INCLUDING INCREASED EXPRESSION OF ONCOGENIC MEDIATORS, INCREASED TELOMERASE TRANSCRIPTS, AND INCREASED GROWTH/MIGRATORY POTENTIAL. HEREIN, WE EXTEND THESE STUDIES BY IMPLEMENTING AN INTEGRATED TRANSCRIPTOMIC AND MASS SPECTROMETRY-BASED PROTEOMICS APPROACH TO IDENTIFY GLOBAL MIRNA AND PROTEIN ALTERATIONS, FOR WHICH WE ALSO INVESTIGATE A SUBSET OF THESE TARGETS TO IRON-INDUCED FUNCTIONAL ALTERATIONS. PROTEOMIC ANALYSIS IDENTIFIED > 4500 PROTEINS, OF WHICH 243 TARGETS WERE DIFFERENTIALLY EXPRESSED. SIXTY-FIVE DIFFERENTIALLY EXPRESSED MIRNAS WERE IDENTIFIED, OF WHICH 35 WERE ASSOCIATED WITH THE "TOP" PROTEOMIC MOLECULES (> FOURFOLD CHANGE) IDENTIFIED BY INGENUITY PATHWAY ANALYSIS. TWENTY OF THESE 35 MIRNAS ARE AT THE 14Q32 LOCUS (ENCODING A CLUSTER OF 54 MIRNAS) WITH POTENTIAL TO BE REGULATED BY DNA METHYLATION AND HISTONE DEACETYLATION. AT 14Q32, MIR-432-5P AND MIR-127-3P WERE ~ 100-FOLD DOWNREGULATED WHEREAS MIR-138-5P WAS 16-FOLD DOWNREGULATED AT 3P21 IN CHRONIC IRON-EXPOSED FTSECS. COMBINATORIAL TREATMENT WITH METHYLTRANSFERASE AND DEACETYLATION INHIBITORS REVERSED EXPRESSION OF THESE MIRNAS, SUGGESTING CHRONIC IRON EXPOSURE ALTERS MIRNA EXPRESSION VIA EPIGENETIC ALTERATIONS. IN ADDITION, PAX8, AN IMPORTANT TARGET IN HGSOC AND A POTENTIAL MIRNA TARGET (FROM IPA) WAS EPIGENETICALLY DEREGULATED IN IRON-EXPOSED FTSECS. HOWEVER, BOTH PAX8 AND ALDH1A2 (ANOTHER IPA-PREDICTED TARGET) WERE EXPERIMENTALLY IDENTIFIED TO BE INDEPENDENTLY REGULATED BY THESE MIRNAS ALTHOUGH TERT RNA WAS PARTIALLY REGULATED BY MIR-138-5P. INTERESTINGLY, OVEREXPRESSION OF MIR-432-5P DIMINISHED CELL NUMBERS INDUCED BY LONG-TERM IRON EXPOSURE IN FTSECS. COLLECTIVELY, OUR GLOBAL PROFILING APPROACHES UNCOVERED PATTERNS OF MIRNA AND PROTEOMIC ALTERATIONS THAT MAY BE REGULATED BY GENOME-WIDE EPIGENETIC ALTERATIONS AND CONTRIBUTE TO FUNCTIONAL ALTERATIONS INDUCED BY CHRONIC IRON EXPOSURE IN FTSECS. THIS STUDY MAY PROVIDE A PLATFORM TO IDENTIFY FUTURE BIOMARKERS FOR EARLY OVARIAN CANCER DETECTION AND NEW TARGETS FOR THERAPY. 2021 7 3762 38 INTEGRATING THE TUMOR-SUPPRESSIVE ACTIVITY OF MASPIN WITH P53 IN RETUNING THE EPITHELIAL HOMEOSTASIS: A WORKING HYPOTHESIS AND APPLICABLE PROSPECTS. EPITHELIAL MALIGNANT TRANSFORMATION AND TUMOROUS DEVELOPMENT WERE BELIEVED TO BE CLOSELY ASSOCIATED WITH THE LOSS OF ITS MICROENVIRONMENT INTEGRITY AND HOMEOSTASIS. THE TUMOR-SUPPRESSIVE MOLECULES MASPIN AND P53 WERE DEMONSTRATED TO PLAY A CRUCIAL ROLE IN BODY EPITHELIAL AND IMMUNE HOMEOSTASIS. DOWNREGULATION OF MASPIN AND MUTATION OF P53 WERE FREQUENTLY ASSOCIATED WITH MALIGNANT TRANSFORMATION AND POOR PROGNOSIS IN VARIOUS HUMAN CANCERS. IN THIS REVIEW, WE FOCUSED ON SUMMARIZING THE PROGRESS OF THE MOLECULAR NETWORK OF MASPIN IN STUDYING EPITHELIAL TUMOROUS DEVELOPMENT AND ITS RESPONSE TO CLINIC TREATMENT AND TRY TO CLARIFY THE UNDERLYING ANTITUMOR MECHANISM. NOTABLY, MASPIN EXPRESSION WAS REPORTED TO BE TRANSCRIPTIONALLY ACTIVATED BY P53, AND THE TRANSCRIPTIONAL ACTIVITY OF P53 WAS DEMONSTRATED TO BE ENHANCED BY ITS ACETYLATION THROUGH INHIBITION OF HDAC1. AS AN ENDOGENOUS INHIBITOR OF HDAC1, MASPIN POSSIBLY POTENTIATES THE TRANSCRIPTIONAL ACTIVITY OF P53 BY ACETYLATING THE P53 PROTEIN. HEREBY, IT COULD FORM A "SELF-PROPELLING" ANTITUMOR MECHANISM. THUS, WE SUMMARIZED THAT, UPON STIMULATION OF CELLULAR STRESS AND BY INTEGRATING WITH P53, THE AROUSED MASPIN PLAYED THE EPIGENETIC SURVEILLANT ROLE TO PREVENT THE EPITHELIAL DIGRESSIONAL PROCESS AND RETUNE THE EPITHELIAL HOMEOSTASIS, WHICH IS INVOLVED IN ACTIVATING HOST IMMUNE SURVEILLANCE, REGULATING THE INFLAMMATORY FACTORS, AND FINE-TUNING ITS ASSOCIATED CELL SIGNALING PATHWAYS. CONSEQUENTIALLY, IN A NORMAL PHYSIOLOGICAL CONDITION, ACTIVATION OF THE ABOVE "SELF-PROPELLING" ANTITUMOR MECHANISM OF MASPIN AND P53 COULD REDUCE CELLULAR STRESS (E.G., CHRONIC INFECTION/INFLAMMATION, OXIDATIVE STRESS, TRANSFORMATION) EFFECTIVELY AND ACHIEVE CANCER PREVENTION. MEANWHILE, DESIGNING A STRATEGY OF MIMICKING MASPIN'S EPIGENETIC REGULATION ACTIVITY WITH INTEGRATING P53 TUMOR-SUPPRESSIVE ACTIVITY COULD ENHANCE THE CHEMOTHERAPY EFFICACY THEORETICALLY IN A PATHOLOGICAL CONDITION OF CANCER. 2022 8 2446 42 EPIGENETIC STRATEGIES SYNERGIZE WITH PD-L1/PD-1 TARGETED CANCER IMMUNOTHERAPIES TO ENHANCE ANTITUMOR RESPONSES. IMMUNOTHERAPY STRATEGIES TARGETING THE PROGRAMMED CELL DEATH LIGAND 1 (PD-L1)/PROGRAMMED CELL DEATH 1 (PD-1) PATHWAY IN CLINICAL TREATMENTS HAVE ACHIEVED REMARKABLE SUCCESS IN TREATING MULTIPLE TYPES OF CANCER. HOWEVER, OWING TO THE HETEROGENEITY OF TUMORS AND INDIVIDUAL IMMUNE SYSTEMS, PD-L1/PD-1 BLOCKADE STILL SHOWS SLOW RESPONSE RATES IN CONTROLLING MALIGNANCIES IN MANY PATIENTS. ACCUMULATING EVIDENCE HAS SHOWN THAT AN EFFECTIVE RESPONSE TO ANTI-PD-L1/ANTI-PD-1 THERAPY REQUIRES ESTABLISHING AN INTEGRATED IMMUNE CYCLE. DAMAGE IN ANY STEP OF THE IMMUNE CYCLE IS ONE OF THE MOST IMPORTANT CAUSES OF IMMUNOTHERAPY FAILURE. IMPAIRMENTS IN THE IMMUNE CYCLE CAN BE RESTORED BY EPIGENETIC MODIFICATION, INCLUDING REPROGRAMMING THE ENVIRONMENT OF TUMOR-ASSOCIATED IMMUNITY, ELICITING AN IMMUNE RESPONSE BY INCREASING THE PRESENTATION OF TUMOR ANTIGENS, AND BY REGULATING T CELL TRAFFICKING AND REACTIVATION. THUS, A RATIONAL COMBINATION OF PD-L1/PD-1 BLOCKADE AND EPIGENETIC AGENTS MAY OFFER GREAT POTENTIAL TO RETRAIN THE IMMUNE SYSTEM AND TO IMPROVE CLINICAL OUTCOMES OF CHECKPOINT BLOCKADE THERAPY. 2020 9 6421 37 THE THERAPEUTIC PROPERTIES OF RESMINOSTAT FOR HEPATOCELLULAR CARCINOMA. HEPATOCELLULAR CARCINOMA (HCC) IS THE MOST COMMON FORM OF PRIMARY LIVER CANCER WITH INCREASES IN NEW CASES BEING REPORTED ANNUALLY. HISTOPATHOLOGISTS HAVE IDENTIFIED HEPATIC STEATOSIS AS A CHARACTERISTIC OF A BROAD RANGE OF CHRONIC LIVER DISEASES THAT ARE ASSOCIATED WITH THE ONSET AND DEVELOPMENT OF HCC. IN THIS CONTEXT, EPIGENETIC MODIFICATIONS MAY SERVE AS PRECANCEROUS FACTORS PREDISPOSING NORMAL CELLS TO THE INITIATION OF CARCINOGENESIS. THIS STUDY DEMONSTRATED THAT HEPATIC TUMORIGENESIS AND DIFFERENTIATED ADIPOCYTES MAY MODULATE BOTH GLOBAL HISTONE DEACETYLASE (HDAC) EXPRESSION AND SPECIFIC CLASS I HDAC GENES IN THE TUMOUR MICROENVIRONMENT. THE NOVEL CLASS I HDAC INHIBITOR RESMINOSTAT WAS SHOWN TO REDUCE THE PROLIFERATION OF HCC CELLS ALONG WITH ITS SPECIFICITY IN TARGETING CLASS I HDACS AND ONCOGENES. THE COMBINED EFFECT OF RESMINOSTAT WITH SEVERAL PHARMACEUTICAL AGENTS SUCH AS SORAFENIB, CISPLATIN AND DOXORUBICIN WAS ALSO DEMONSTRATED. THE INHIBITION OF HEAT SHOCK PROTEIN 90 (HSP90) HAS BEEN DEMONSTRATED AS A POTENTIAL THERAPEUTIC OPTION FOR HCC. IN LINE WITH THIS, THE SPECIFIC HSP90 INHIBITOR 17-(ALLYLAMINO)-17-DEMETHOXYGELDANAMYCIN (17-AAG) WAS SELECTED AND IT WAS FOUND THAT THE COMBINATION OF RESMINOSTAT AND 17-AAG MAY PROVIDE A "SMART" CLINICAL STRATEGY FOR HCC PATIENTS BY TARGETING CELLULAR COMMUNICATION WITHIN THE TUMOUR MICROENVIRONMENT. THIS STUDY PROVIDES AN INSIGHT INTO THE USE OF RESMINOSTAT AS AN EPIGENETIC BASED THERAPEUTIC FOR HCC ALONG WITH OTHER PHARMACEUTICAL OPTIONS, IN PARTICULAR BY TARGETING THE CELL-TO-CELL COMMUNICATION THAT OCCURS BETWEEN HEPATOMA AND ADIPOCYTES. 2018 10 4002 38 LOSS OF P120 CATENIN AND LINKS TO MITOTIC ALTERATIONS, INFLAMMATION, AND SKIN CANCER. TUMOR FORMATION INVOLVES EPIGENETIC MODIFICATIONS AND MICROENVIRONMENTAL CHANGES AS WELL AS CUMULATIVE GENETIC ALTERATIONS ENCOMPASSING SOMATIC MUTATIONS, LOSS OF HETEROZYGOSITY, AND ANEUPLOIDY. HERE, WE SHOW THAT CONDITIONAL TARGETING OF P120 CATENIN IN MICE LEADS TO PROGRESSIVE DEVELOPMENT OF SKIN NEOPLASIAS ASSOCIATED WITH INTRINSIC NF-KAPPAB ACTIVATION. WE FIND THAT, SIMILARLY, SQUAMOUS CELL CARCINOMAS IN HUMANS DISPLAY ALTERED P120 AND ACTIVATED NF-KAPPAB. WE SHOW THAT EPIDERMAL HYPERPROLIFERATION ARISING FROM P120 LOSS CAN BE ABROGATED BY IKAPPAB KINASE 2 INHIBITORS. ALTHOUGH THIS UNDERSCORES THE IMPORTANCE OF THIS PATHWAY, THE ROLE OF NF-KAPPAB IN HYPERPROLIFERATION APPEARS ROOTED IN ITS IMPACT ON EPIDERMAL MICROENVIRONMENT BECAUSE AS P120-NULL KERATINOCYTES DISPLAY A GROWTH-ARRESTED PHENOTYPE IN CULTURE. WE TRACE THIS TO A MITOTIC DEFECT, RESULTING IN UNSTABLE, BINUCLEATED CELLS IN VITRO AND IN VIVO. WE SHOW THAT THE ABNORMAL MITOSES CAN BE AMELIORATED BY INHIBITING RHOA, THE ACTIVITY OF WHICH IS ABNORMALLY HIGH. CONVERSELY, WE CAN ELICIT SUCH MITOTIC DEFECTS IN CONTROL KERATINOCYTES BY ELEVATING RHOA ACTIVITY. THE ABILITY OF P120 DEFICIENCY TO ELICIT MITOTIC ALTERATIONS AND CHRONIC INFLAMMATORY RESPONSES, THAT TOGETHER MAY FACILITATE THE DEVELOPMENT OF GENETIC INSTABILITY IN VIVO, PROVIDES INSIGHTS INTO WHY IT FIGURES SO PROMINENTLY IN SKIN CANCER PROGRESSION. 2008 11 3899 27 LATE NEUROLOGICAL CONSEQUENCES OF ZIKA VIRUS INFECTION: RISK FACTORS AND PHARMACEUTICAL APPROACHES. ZIKA VIRUS (ZIKV) INFECTION WAS HISTORICALLY CONSIDERED A DISEASE WITH MILD SYMPTOMS AND NO MAJOR CONSEQUENCES TO HUMAN HEALTH. HOWEVER, SEVERAL LONG-TERM, LATE ONSET, AND CHRONIC NEUROLOGICAL COMPLICATIONS, BOTH IN CONGENITALLY-EXPOSED BABIES AND IN ADULT PATIENTS, HAVE BEEN REPORTED AFTER ZIKV INFECTION, ESPECIALLY AFTER THE 2015 EPIDEMICS IN THE AMERICAN CONTINENT. THE DEVELOPMENT OR SEVERITY OF THESE CONDITIONS CANNOT BE FULLY PREDICTED, BUT IT IS POSSIBLE THAT GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS MAY CONTRIBUTE TO DETERMINE ZIKV INFECTION OUTCOMES. THIS REINFORCES THE IMPORTANCE THAT INDIVIDUALS EXPOSED TO ZIKV ARE SUBMITTED TO LONG-TERM CLINICAL SURVEILLANCE AND HIGHLIGHTS THE URGENT NEED FOR THE DEVELOPMENT OF THERAPEUTIC APPROACHES TO REDUCE OR ELIMINATE THE NEUROLOGICAL BURDEN OF INFECTION. HERE, WE REVIEW THE EPIDEMIOLOGY OF ZIKV-ASSOCIATED NEUROLOGICAL COMPLICATIONS AND THE ROLE OF FACTORS THAT MAY INFLUENCE DISEASE OUTCOME. MOREOVER, WE DISCUSS EXPERIMENTAL AND CLINICAL EVIDENCE OF DRUGS THAT HAVE SHOWN PROMISING RESULTS IN VITRO OR IN VITRO AGAINST VIRAL REPLICATION AND AND/OR ZIKV-INDUCED NEUROTOXICITY. 2019 12 4665 28 NEW INSIGHTS AND ADVANCES IN PATHOGENESIS AND TREATMENT OF VERY EARLY ONSET INFLAMMATORY BOWEL DISEASE. VERY EARLY ONSET INFLAMMATORY BOWEL DISEASE (VEO-IBD) IS CHARACTERIZED BY MULTIFACTORIAL CHRONIC RECURRENT INTESTINAL INFLAMMATION. COMPARED WITH ELDERLY PATIENTS, THOSE WITH VEO-IBD HAVE A MORE SERIOUS CONDITION, NOT RESPONSIVE TO CONVENTIONAL TREATMENTS, WITH A POOR PROGNOSIS. RECENT STUDIES FOUND THAT GENETIC AND IMMUNOLOGIC ABNORMALITIES ARE CLOSELY RELATED TO VEO-IBD. INTESTINAL IMMUNE HOMEOSTASIS MONOGENIC DEFECTS (IIHMDS) ARE CHANGED THROUGH VARIOUS MECHANISMS. RECENT STUDIES HAVE ALSO REVEALED THAT ABNORMALITIES IN GENES AND IMMUNE MOLECULAR MECHANISMS ARE CLOSELY RELATED TO VEO-IBD. IIHMDS CHANGE THROUGH VARIOUS MECHANISMS. EPIGENETIC FACTORS CAN MEDIATE THE INTERACTION BETWEEN THE ENVIRONMENT AND GENOME, AND GENETIC FACTORS AND IMMUNE MOLECULES MAY BE INVOLVED IN THE PATHOGENESIS OF THE ENVIRONMENT AND GUT MICROBIOTA. THESE DISCOVERIES WILL PROVIDE NEW DIRECTIONS AND IDEAS FOR THE TREATMENT OF VEO-IBD. 2022 13 5688 37 SILENCING EFFECTS OF MUTANT RAS SIGNALLING ON TRANSCRIPTOMES. MUTATED GENES OF THE RAS FAMILY ENCODING SMALL GTP-BINDING PROTEINS DRIVE NUMEROUS CANCERS, INCLUDING PANCREATIC, COLON AND LUNG TUMORS. BESIDES THE NUMEROUS EFFECTS OF MUTANT RAS GENE EXPRESSION ON ABERRANT PROLIFERATION, TRANSFORMED PHENOTYPES, METABOLISM, AND THERAPY RESISTANCE, THE MOST STRIKING CONSEQUENCES OF CHRONIC RAS ACTIVATION ARE CHANGES OF THE GENETIC PROGRAM. BY PERFORMING SYSTEMATIC GENE EXPRESSION STUDIES IN CELLULAR MODELS THAT ALLOW COMPARISONS OF PRE-NEOPLASTIC WITH RAS-TRANSFORMED CELLS, WE AND OTHERS HAVE ESTIMATED THAT 7 PERCENT OR MORE OF ALL TRANSCRIPTS ARE ALTERED IN CONJUNCTION WITH THE EXPRESSION OF THE ONCOGENE. IN THIS CONTEXT, THE NUMBER OF UP-REGULATED TRANSCRIPTS APPROXIMATES THAT OF DOWN-REGULATED TRANSCRIPTS. WHILE UP-REGULATED TRANSCRIPTION FACTORS SUCH AS MYC, FOSL1, AND HMGA2 HAVE BEEN IDENTIFIED AND CHARACTERIZED AS RAS-RESPONSIVE DRIVERS OF THE ALTERED TRANSCRIPTOME, THE SUPPRESSED FACTORS HAVE BEEN LESS WELL STUDIED AS POTENTIAL REGULATORS OF THE GENETIC PROGRAM AND TRANSFORMED PHENOTYPE IN THE BREADTH OF THEIR OCCURRENCE. WE THEREFORE HAVE COLLECTED INFORMATION ON DOWNREGULATED RAS-RESPONSIVE FACTORS AND DISCUSS THEIR POTENTIAL ROLE AS TUMOR SUPPRESSORS THAT ARE LIKELY TO ANTAGONIZE ACTIVE CANCER DRIVERS. TO BETTER UNDERSTAND THE ACTIVE MECHANISMS THAT ENTAIL ANTI-RAS FUNCTION AND THOSE THAT LEAD TO LOSS OF TUMOR SUPPRESSOR ACTIVITY, WE FOCUS ON THE TUMOR SUPPRESSOR HREV107 (ALIAS PLAAT3 [PHOSPHOLIPASE A AND ACYLTRANSFERASE 3], PLA2G16 [PHOSPHOLIPASE A2, GROUP XVI] AND HRASLS3 [HRAS-LIKE SUPPRESSOR 3]). INACTIVATING HREV107 MUTATIONS IN TUMORS ARE EXTREMELY RARE, HENCE EPIGENETIC CAUSES MODULATED BY THE RAS PATHWAY ARE LIKELY TO LEAD TO DOWN-REGULATION AND LOSS OF FUNCTION. 2023 14 4968 34 PATHOLOGICAL MECHANISMS AND THERAPEUTIC OUTLOOKS FOR ARTHROFIBROSIS. ARTHROFIBROSIS IS A FIBROTIC JOINT DISORDER THAT BEGINS WITH AN INFLAMMATORY REACTION TO INSULTS SUCH AS INJURY, SURGERY AND INFECTION. EXCESSIVE EXTRACELLULAR MATRIX AND ADHESIONS CONTRACT POUCHES, BURSAE AND TENDONS, CAUSE PAIN AND PREVENT A NORMAL RANGE OF JOINT MOTION, WITH DEVASTATING CONSEQUENCES FOR PATIENT QUALITY OF LIFE. ARTHROFIBROSIS AFFECTS PEOPLE OF ALL AGES, WITH PUBLISHED RATES VARYING. THE RISK FACTORS AND BEST MANAGEMENT STRATEGIES ARE LARGELY UNKNOWN DUE TO A POOR UNDERSTANDING OF THE PATHOLOGY AND LACK OF DIAGNOSTIC BIOMARKERS. HOWEVER, CURRENT RESEARCH INTO THE PATHOGENESIS OF FIBROSIS IN ORGANS NOW INFORMS THE UNDERSTANDING OF ARTHROFIBROSIS. THE PROCESS BEGINS WHEN STRESS SIGNALS STIMULATE IMMUNE CELLS. THE RESULTING CASCADE OF CYTOKINES AND MEDIATORS DRIVES FIBROBLASTS TO DIFFERENTIATE INTO MYOFIBROBLASTS, WHICH SECRETE FIBRILLAR COLLAGENS AND TRANSFORMING GROWTH FACTOR-BETA (TGF-BETA). POSITIVE FEEDBACK NETWORKS THEN DYSREGULATE PROCESSES THAT NORMALLY TERMINATE HEALING PROCESSES. WE PROPOSE TWO SUBTYPES OF ARTHROFIBROSIS OCCUR: ACTIVE ARTHROFIBROSIS AND RESIDUAL ARTHROFIBROSIS. IN THE LATTER THE FIBROGENIC PROCESSES HAVE RESOLVED BUT THE JOINT REMAINS STIFF. THE BEST THERAPEUTIC APPROACH FOR EACH SUBTYPE MAY DIFFER SIGNIFICANTLY. TREATMENT TYPICALLY INVOLVES SURGERY, HOWEVER, A PHARMACOLOGICAL APPROACH TO CORRECT DYSREGULATED CELL SIGNALLING COULD BE MORE EFFECTIVE. RECENT RESEARCH SHOWS THAT MYOFIBROBLASTS ARE CAPABLE OF REVERSING DIFFERENTIATION, AND UNDERSTANDING THE MECHANISMS OF PATHOGENESIS AND RESOLUTION WILL BE ESSENTIAL FOR THE DEVELOPMENT OF CELL-BASED TREATMENTS. THERAPIES WITH SIGNIFICANT PROMISE ARE CURRENTLY AVAILABLE, WITH MORE IN DEVELOPMENT, INCLUDING THOSE THAT INHIBIT TGF-BETA SIGNALLING AND EPIGENETIC MODIFICATIONS. THIS REVIEW FOCUSES ON PATHOGENESIS OF STERILE ARTHROFIBROSIS AND THERAPEUTIC TREATMENTS. 2019 15 2568 28 EPIGENETICS OF ALCOHOL-RELATED LIVER DISEASES. ALCOHOL-RELATED LIVER DISEASE (ARLD) IS A PRIMARY CAUSE OF CHRONIC LIVER DISEASE IN THE UNITED STATES. DESPITE ADVANCES IN THE DIAGNOSIS AND MANAGEMENT OF ARLD, IT REMAINS A MAJOR PUBLIC HEALTH PROBLEM ASSOCIATED WITH SIGNIFICANT MORBIDITY AND MORTALITY, EMPHASISING THE NEED TO ADOPT NOVEL APPROACHES TO THE STUDY OF ARLD AND ITS COMPLICATIONS. EPIGENETIC CHANGES ARE INCREASINGLY BEING RECOGNISED AS CONTRIBUTING TO THE PATHOGENESIS OF MULTIPLE DISEASE STATES. HARNESSING THE POWER OF INNOVATIVE TECHNOLOGIES FOR THE STUDY OF EPIGENETICS (E.G., NEXT-GENERATION SEQUENCING, DNA METHYLATION ASSAYS, HISTONE MODIFICATION PROFILING AND COMPUTATIONAL TECHNIQUES LIKE MACHINE LEARNING) HAS RESULTED IN A SEISMIC SHIFT IN OUR UNDERSTANDING OF THE PATHOPHYSIOLOGY OF ARLD. KNOWLEDGE OF THESE TECHNIQUES AND ADVANCES IS OF PARAMOUNT IMPORTANCE FOR THE PRACTICING HEPATOLOGIST AND RESEARCHERS ALIKE. ACCORDINGLY, IN THIS REVIEW ARTICLE WE WILL SUMMARISE THE CURRENT KNOWLEDGE ABOUT ALCOHOL-INDUCED EPIGENETIC ALTERATIONS IN THE CONTEXT OF ARLD, INCLUDING BUT NOT LIMITED TO, DNA HYPER/HYPO METHYLATION, HISTONE MODIFICATIONS, CHANGES IN NON-CODING RNA, 3D CHROMATIN ARCHITECTURE AND ENHANCER-PROMOTER INTERACTIONS. ADDITIONALLY, WE WILL DISCUSS THE STATE-OF-THE-ART TECHNIQUES USED IN THE STUDY OF ARLD (E.G. SINGLE-CELL SEQUENCING). WE WILL ALSO HIGHLIGHT THE EPIGENETIC REGULATION OF CHEMOKINES AND THEIR PROINFLAMMATORY ROLE IN THE CONTEXT OF ARLD. LASTLY, WE WILL EXAMINE THE CLINICAL APPLICATIONS OF EPIGENETICS IN THE DIAGNOSIS AND MANAGEMENT OF ARLD. 2022 16 4414 32 MOLECULAR AND CELLULAR MECHANISMS OF PROPOLIS AND ITS POLYPHENOLIC COMPOUNDS AGAINST CANCER. IN RECENT YEARS, INTEREST IN NATURAL PRODUCTS SUCH AS ALTERNATIVE SOURCES OF PHARMACEUTICALS FOR NUMEROUS CHRONIC DISEASES, INCLUDING TUMORS, HAS BEEN RENEWED. PROPOLIS, A NATURAL PRODUCT COLLECTED BY HONEYBEES, AND POLYPHENOLIC/FLAVONOID PROPOLIS-RELATED COMPONENTS MODULATE ALL STEPS OF THE CANCER PROGRESSION PROCESS. ANTICANCER ACTIVITY OF PROPOLIS AND ITS COMPOUNDS RELIES ON VARIOUS MECHANISMS: CELL-CYCLE ARREST AND ATTENUATION OF CANCER CELLS PROLIFERATION, REDUCTION IN THE NUMBER OF CANCER STEM CELLS, INDUCTION OF APOPTOSIS, MODULATION OF ONCOGENE SIGNALING PATHWAYS, INHIBITION OF MATRIX METALLOPROTEINASES, PREVENTION OF METASTASIS, ANTI-ANGIOGENESIS, ANTI-INFLAMMATORY EFFECTS ACCOMPANIED BY THE MODULATION OF THE TUMOR MICROENVIRONMENT (BY MODIFYING MACROPHAGE ACTIVATION AND POLARIZATION), EPIGENETIC REGULATION, ANTIVIRAL AND BACTERICIDAL ACTIVITIES, MODULATION OF GUT MICROBIOTA, AND ATTENUATION OF CHEMOTHERAPY-INDUCED DELETERIOUS SIDE EFFECTS. INGREDIENTS FROM PROPOLIS ALSO "SENSITIZE" CANCER CELLS TO CHEMOTHERAPEUTIC AGENTS, LIKELY BY BLOCKING THE ACTIVATION OF THE TRANSCRIPTION FACTOR NUCLEAR FACTOR KAPPA-LIGHT-CHAIN-ENHANCER OF ACTIVATED B CELLS (NF-KAPPAB). IN THIS REVIEW, WE SUMMARIZE THE CURRENT KNOWLEDGE RELATED TO THE THE EFFECTS OF FLAVONOIDS AND OTHER POLYPHENOLIC COMPOUNDS FROM PROPOLIS ON TUMOR GROWTH AND METASTASIZING ABILITY, AND DISCUSS POSSIBLE MOLECULAR AND CELLULAR MECHANISMS INVOLVED IN THE MODULATION OF INFLAMMATORY PATHWAYS AND CELLULAR PROCESSES THAT AFFECT SURVIVAL, PROLIFERATION, INVASION, ANGIOGENESIS, AND METASTASIS OF THE TUMOR. 2022 17 222 29 ACUTE LIVER STEATOSIS TRANSLATIONALLY CONTROLS THE EPIGENETIC REGULATOR MIER1 TO PROMOTE LIVER REGENERATION IN A STUDY WITH MALE MICE. THE EARLY PHASE LIPID ACCUMULATION IS ESSENTIAL FOR LIVER REGENERATION. HOWEVER, WHETHER THIS ACUTE LIPID ACCUMULATION CAN SERVE AS SIGNALS TO DIRECT LIVER REGENERATION RATHER THAN SIMPLY PROVIDING BUILDING BLOCKS FOR CELL PROLIFERATION REMAINS UNCLEAR. THROUGH IN VIVO CRISPR SCREENING, WE IDENTIFY MIER1 (MESODERM INDUCTION EARLY RESPONSE 1) AS A KEY EPIGENETIC REGULATOR THAT BRIDGES THE ACUTE LIPID ACCUMULATION AND CELL CYCLE GENE EXPRESSION DURING LIVER REGENERATION IN MALE ANIMALS. PHYSIOLOGICALLY, LIVER ACUTE LIPID ACCUMULATION INDUCES THE PHOSPHORYLATION OF EIF2S1(EUKARYOTIC TRANSLATION INITIATION FACTOR 2), WHICH CONSEQUENTLY ATTENUATED MIER1 TRANSLATION. MIER1 DOWNREGULATION IN TURN PROMOTES CELL CYCLE GENE EXPRESSION AND REGENERATION THROUGH CHROMATIN REMODELING. IMPORTANTLY, THE LIPIDS-EIF2S1-MIER1 PATHWAY IS IMPAIRED IN ANIMALS WITH CHRONIC LIVER STEATOSIS; WHEREAS MIER1 DEPLETION SIGNIFICANTLY IMPROVES REGENERATION IN THESE ANIMALS. TAKEN TOGETHER, OUR STUDIES IDENTIFY AN EPIGENETIC MECHANISM BY WHICH THE EARLY PHASE LIPID REDISTRIBUTION FROM ADIPOSE TISSUE TO LIVER DURING REGENERATION IMPACTS HEPATOCYTE PROLIFERATION, AND SUGGEST A POTENTIAL STRATEGY TO BOOST LIVER REGENERATION. 2023 18 3465 32 HYPOTHESIS: REGULATION OF NEUROPLASTICITY MAY INVOLVE I-MOTIF AND G-QUADRUPLEX DNA FORMATION MODULATED BY EPIGENETIC MECHANISMS. RECENT STUDIES DEMONSTRATED THE EXISTENCE IN VIVO OF VARIOUS FUNCTIONAL DNA STRUCTURES THAT DIFFER FROM THE DOUBLE HELIX. THE G-QUADRUPLEX (G4) AND INTERCALATED MOTIF (I-MOTIF OR IM) DNA STRUCTURES ARE FORMED AS KNOTS WHERE, CORRESPONDINGLY, GUANINES OR CYTOSINES ON THE SAME STRAND OF DNA BIND TO EACH OTHER. THERE ARE GROUNDS TO BELIEVE THAT G4 AND IM SEQUENCES PLAY A SIGNIFICANT ROLE IN REGULATING GENE EXPRESSION CONSIDERING THEIR TENDENCY TO BE FOUND IN OR NEAR REGULATORY SITES (SUCH AS PROMOTERS, ENHANCERS, AND TELOMERES) AS WELL AS THE CORRELATION BETWEEN THE PREVALENCE OF G4 OR IM CONFORMATIONS AND SPECIFIC PHASES OF CELL CYCLE. NOTABLY, G4 AND IM CAPABLE SEQUENCES TEND TO BE FOUND ON THE OPPOSITE STRANDS OF THE SAME DNA SITE WITH AT MOST ONE OF THE TWO STRUCTURES FORMED AT ANY GIVEN TIME. THE RECENT EVIDENCE THAT K(+), MG(2+) CONCENTRATIONS DIRECTLY AFFECT IM FORMATION (AND LIKELY G4 FORMATION INDIRECTLY) LEAD US TO BELIEVE THAT THESE STRUCTURES MAY PLAY A MAJOR ROLE IN SYNAPTIC PLASTICITY OF NEURONS, AND, THEREFORE, IN A VARIETY OF CENTRAL NERVOUS SYSTEM (CNS) FUNCTIONS INCLUDING MEMORY, LEARNING, HABITUAL BEHAVIORS, PAIN PERCEPTION AND OTHERS. FURTHERMORE, EPIGENETIC MECHANISMS, WHICH HAVE AN IMPORTANT ROLE IN SYNAPTIC PLASTICITY AND MEMORY FORMATION, WERE ALSO SHOWN TO INFLUENCE FORMATION AND STABILITY OF G4S AND IMS. OUR HYPOTHESIS IS THAT NON-CANONICAL DNA AND RNA STRUCTURES COULD BE AN INTEGRAL PART OF NEUROPLASTICITY CONTROL VIA GENE EXPRESSION REGULATION AT THE LEVEL OF TRANSCRIPTION, TRANSLATION AND SPLICING. WE PROPOSE THAT THE REGULATORY ACTIVITY OF DNA IM AND G4 STRUCTURES IS MODULATED BY DNA METHYLATION/DEMETHYLATION OF THE IM AND/OR G4 SEQUENCES, WHICH FACILITATES THE SWITCH BETWEEN CANONICAL AND NON-CANONICAL CONFORMATION. OTHER NEURONAL MECHANISMS INTERACTING WITH THE FORMATION AND REGULATORY ACTIVITY OF NON-CANONICAL DNA AND RNA STRUCTURES, PARTICULARLY G4, IM AND TRIPLEXES, MAY INVOLVE MICRORNAS AS WELL AS ION AND PROTON FLUXES. WE ARE PROPOSING EXPERIMENTS IN ACUTE BRAIN SLICES AND IN VIVO TO TEST OUR HYPOTHESIS. THE PROPOSED STUDIES WOULD PROVIDE NEW INSIGHTS INTO FUNDAMENTAL NEURONAL MECHANISMS IN HEALTH AND DISEASE AND POTENTIALLY OPEN NEW AVENUES FOR TREATING MENTAL HEALTH DISORDERS. 2019 19 1260 39 CURRENT VIEWS ON THE INTERPLAY BETWEEN TYROSINE KINASES AND PHOSPHATASES IN CHRONIC MYELOID LEUKEMIA. CHRONIC MYELOID LEUKEMIA (CML) IS A MYELOPROLIFERATIVE DISORDER CHARACTERIZED BY BCR-ABL1 ONCOGENE EXPRESSION. THIS DYSREGULATED PROTEIN-TYROSINE KINASE (PTK) IS KNOWN AS THE PRINCIPAL DRIVER OF THE DISEASE AND IS TARGETED BY TYROSINE KINASE INHIBITORS (TKIS). EXTENSIVE DOCUMENTATION HAS ELUCIDATED HOW THE TRANSFORMATION OF MALIGNANT CELLS IS CHARACTERIZED BY MULTIPLE GENETIC/EPIGENETIC CHANGES LEADING TO THE LOSS OF TUMOR-SUPPRESSOR GENES FUNCTION OR PROTO-ONCOGENES EXPRESSION. THE IMPAIRMENT OF ADEQUATE LEVELS OF SUBSTRATES PHOSPHORYLATION, THUS AFFECTING THE BALANCE PTKS AND PROTEIN PHOSPHATASES (PPS), REPRESENTS A WELL-ESTABLISHED CELLULAR MECHANISM TO ESCAPE FROM SELF-LIMITING SIGNALS. IN THIS REVIEW, WE FOCUS OUR ATTENTION ON THE CHARACTERIZATION OF AND INTERACTIONS BETWEEN PTKS AND PPS, EMPHASIZING THEIR BIOLOGICAL ROLES IN DISEASE EXPANSION, THE REGULATION OF LSCS AND TKI RESISTANCE. WE DECIDED TO SEPARATE THOSE PPS THAT HAVE BEEN VALIDATED IN PRIMARY CELL MODELS OR LEUKEMIA MOUSE MODELS FROM THOSE WHOSE STUDIES HAVE BEEN PERFORMED ONLY IN CELL LINES (AND, THUS, REQUIRE VALIDATION), AS THERE MAY BE DIFFERENCES IN THE MANNER THAT THE ASSOCIATED PATHWAYS ARE MODIFIED UNDER THESE TWO CONDITIONS. THIS REVIEW SUMMARIZES THE ROLES OF DIVERSE PPS, WITH HOPE THAT BETTER KNOWLEDGE OF THE INTERPLAY AMONG PHOSPHATASES AND KINASES WILL EVENTUALLY RESULT IN A BETTER UNDERSTANDING OF THIS DISEASE AND CONTRIBUTE TO ITS ERADICATION. 2021 20 3327 28 HISTONE DEACETYLASE 4 PROMOTES CHOLESTATIC LIVER INJURY IN THE ABSENCE OF PROHIBITIN-1. PROHIBITIN-1 (PHB1) IS AN EVOLUTIONARILY CONSERVED PLEIOTROPIC PROTEIN THAT PARTICIPATES IN DIVERSE PROCESSES DEPENDING ON ITS SUBCELLULAR LOCALIZATION AND INTERACTOME. RECENT DATA HAVE INDICATED A DIVERSE ROLE FOR PHB1 IN THE PATHOGENESIS OF OBESITY, CANCER, AND INFLAMMATORY BOWEL DISEASE, AMONG OTHERS. DATA PRESENTED HERE SUGGEST THAT PHB1 IS ALSO LINKED TO CHOLESTATIC LIVER DISEASE. EXPRESSION OF PHB1 IS MARKEDLY REDUCED IN PATIENTS WITH PRIMARY BILIARY CIRRHOSIS AND BILIARY ATRESIA OR WITH ALAGILLE SYNDROME, TWO MAJOR PEDIATRIC CHOLESTATIC CONDITIONS. IN THE EXPERIMENTAL MODEL OF BILE DUCT LIGATION, SILENCING OF PHB1 INDUCED LIVER FIBROSIS, REDUCED ANIMAL SURVIVAL, AND INDUCED BILE DUCT PROLIFERATION. IMPORTANTLY, THE MODULATORY EFFECT OF PHB1 IS NOT DEPENDENT ON ITS KNOWN MITOCHONDRIAL FUNCTION. ALSO, PHB1 INTERACTS WITH HISTONE DEACETYLASE 4 (HDAC4) IN THE PRESENCE OF BILE ACIDS. HENCE, PHB1 DEPLETION LEADS TO INCREASED NUCLEAR HDAC4 CONTENT AND ITS ASSOCIATED EPIGENETIC CHANGES. REMARKABLY, HDAC4 SILENCING AND THE ADMINISTRATION OF THE HDAC INHIBITOR PARTHENOLIDE DURING OBSTRUCTIVE CHOLESTASIS IN VIVO PROMOTE GENOMIC REPROGRAMMING, LEADING TO REGRESSION OF THE FIBROTIC PHENOTYPE IN LIVER-SPECIFIC PHB1 KNOCKOUT MICE. CONCLUSION: PHB1 IS AN IMPORTANT MEDIATOR OF CHOLESTATIC LIVER INJURY THAT REGULATES THE ACTIVITY OF HDAC4, WHICH CONTROLS SPECIFIC EPIGENETIC MARKERS; THESE RESULTS IDENTIFY POTENTIAL NOVEL STRATEGIES TO TREAT LIVER INJURY AND FIBROSIS, PARTICULARLY AS A CONSEQUENCE OF CHRONIC CHOLESTASIS. 2015