1 6591 110 TUMOR-ASSOCIATED MACROPHAGES AS A PARADIGM OF MACROPHAGE PLASTICITY, DIVERSITY, AND POLARIZATION: LESSONS AND OPEN QUESTIONS. MACROPHAGES ARE PRESENT IN ALL BODY COMPARTMENTS, INCLUDING CANCEROUS TISSUES, AND THEIR FUNCTIONS ARE PROFOUNDLY AFFECTED BY SIGNALS FROM THE MICROENVIRONMENT UNDER HOMEOSTATIC AND PATHOLOGICAL CONDITIONS. TUMOR-ASSOCIATED MACROPHAGES ARE A MAJOR CELLULAR COMPONENT OF CANCER-RELATED INFLAMMATION AND HAVE SERVED AS A PARADIGM FOR THE PLASTICITY AND FUNCTIONAL POLARIZATION OF MONONUCLEAR PHAGOCYTES. TUMOR-ASSOCIATED MACROPHAGES CAN EXERT DUAL INFLUENCE OF CANCER DEPENDING ON THE ACTIVATION STATE, WITH CLASSICALLY ACTIVATED (M1) AND ALTERNATIVELY ACTIVATED (M2) CELLS GENERALLY EXERTING ANTITUMORAL AND PROTUMORAL FUNCTIONS, RESPECTIVELY. THESE ARE EXTREMES IN A CONTINUUM OF POLARIZATION STATES IN A UNIVERSE OF DIVERSITY. TUMOR-ASSOCIATED MACROPHAGES AFFECT VIRTUALLY ALL ASPECTS OF TUMOR TISSUES, INCLUDING STEM CELLS, METABOLISM, ANGIOGENESIS, INVASION, AND METASTASIS. PROGRESS HAS BEEN MADE IN DEFINING SIGNALING MOLECULES, TRANSCRIPTION FACTORS, EPIGENETIC CHANGES, AND REPERTOIRE OF MICRORNAS UNDERLYING MACROPHAGE POLARIZATION. PRECLINICAL AND EARLY CLINICAL DATA SUGGEST THAT MACROPHAGES MAY SERVE AS TOOLS FOR THE DEVELOPMENT OF INNOVATIVE DIAGNOSTIC AND THERAPEUTIC STRATEGIES IN CANCER AND CHRONIC NONRESOLVING INFLAMMATORY DISEASES. 2013 2 5412 37 REGULATION OF ANTITUMOR IMMUNITY BY INFLAMMATION-INDUCED EPIGENETIC ALTERATIONS. CHRONIC INFLAMMATION PROMOTES TUMOR DEVELOPMENT, PROGRESSION, AND METASTATIC DISSEMINATION AND CAUSES TREATMENT RESISTANCE. THE ACCUMULATION OF GENETIC ALTERATIONS AND LOSS OF NORMAL CELLULAR REGULATORY PROCESSES ARE NOT ONLY ASSOCIATED WITH CANCER GROWTH AND PROGRESSION BUT ALSO RESULT IN THE EXPRESSION OF TUMOR-SPECIFIC AND TUMOR-ASSOCIATED ANTIGENS THAT MAY ACTIVATE ANTITUMOR IMMUNITY. THIS ANTAGONISM BETWEEN INFLAMMATION AND IMMUNITY AND THE ABILITY OF CANCER CELLS TO AVOID IMMUNE DETECTION AFFECT THE COURSE OF CANCER DEVELOPMENT AND TREATMENT OUTCOMES. WHILE INFLAMMATION, PARTICULARLY ACUTE INFLAMMATION, SUPPORTS T-CELL PRIMING, ACTIVATION, AND INFILTRATION INTO INFECTED TISSUES, CHRONIC INFLAMMATION IS MOSTLY IMMUNOSUPPRESSIVE. HOWEVER, THE MAIN MECHANISMS THAT DICTATE THE OUTCOME OF THE INFLAMMATION-IMMUNITY INTERPLAY ARE NOT WELL UNDERSTOOD. RECENT DATA SUGGEST THAT INFLAMMATION TRIGGERS EPIGENETIC ALTERATIONS IN CANCER CELLS AND COMPONENTS OF THE TUMOR MICROENVIRONMENT. THESE ALTERATIONS CAN AFFECT AND MODULATE NUMEROUS ASPECTS OF CANCER DEVELOPMENT, INCLUDING TUMOR GROWTH, THE METABOLIC STATE, METASTATIC SPREAD, IMMUNE ESCAPE, AND IMMUNOSUPPRESSIVE OR IMMUNOSUPPORTIVE LEUKOCYTE GENERATION. IN THIS REVIEW, WE DISCUSS THE ROLE OF INFLAMMATION IN INITIATING EPIGENETIC ALTERATIONS IN IMMUNE CELLS, CANCER-ASSOCIATED FIBROBLASTS, AND CANCER CELLS AND SUGGEST HOW AND WHEN EPIGENETIC INTERVENTIONS CAN BE COMBINED WITH IMMUNOTHERAPIES TO IMPROVE THERAPEUTIC OUTCOMES. 2022 3 1482 40 DIVERSITY, MECHANISMS, AND SIGNIFICANCE OF MACROPHAGE PLASTICITY. MACROPHAGES ARE A DIVERSE SET OF CELLS PRESENT IN ALL BODY COMPARTMENTS. THIS DIVERSITY IS IMPRINTED BY THEIR ONTOGENETIC ORIGIN (EMBRYONAL VERSUS ADULT BONE MARROW-DERIVED CELLS); THE ORGAN CONTEXT; BY THEIR ACTIVATION OR DEACTIVATION BY VARIOUS SIGNALS IN THE CONTEXTS OF MICROBIAL INVASION, TISSUE DAMAGE, AND METABOLIC DERANGEMENT; AND BY POLARIZATION OF ADAPTIVE T CELL RESPONSES. CLASSIC ADAPTIVE RESPONSES OF MACROPHAGES INCLUDE TOLERANCE, PRIMING, AND A WIDE SPECTRUM OF ACTIVATION STATES, INCLUDING M1, M2, OR M2-LIKE. MOREOVER, MACROPHAGES CAN RETAIN LONG-TERM IMPRINTING OF MICROBIAL ENCOUNTERS (TRAINED INNATE IMMUNITY). SINGLE-CELL ANALYSIS OF MONONUCLEAR PHAGOCYTES IN HEALTH AND DISEASE HAS ADDED A NEW DIMENSION TO OUR UNDERSTANDING OF THE DIVERSITY OF MACROPHAGE DIFFERENTIATION AND ACTIVATION. EPIGENETIC LANDSCAPES, TRANSCRIPTION FACTORS, AND MICRORNA NETWORKS UNDERLIE THE ADAPTABILITY OF MACROPHAGES TO DIFFERENT ENVIRONMENTAL CUES. MACROPHAGE PLASTICITY, AN ESSENTIAL COMPONENT OF CHRONIC INFLAMMATION, AND ITS INVOLVEMENT IN DIVERSE HUMAN DISEASES, MOST NOTABLY CANCER, IS DISCUSSED HERE AS A PARADIGM. 2020 4 2342 25 EPIGENETIC REGULATION OF MACROPHAGE POLARIZATION AND FUNCTION. MACROPHAGE POLARIZATION REFERS TO DEVELOPMENT OF A SPECIFIC PHENOTYPE IMPORTANT FOR TISSUE HOMEOSTASIS OR HOST DEFENSE IN RESPONSE TO ENVIRONMENTAL CUES. ENVIRONMENTAL FACTORS THAT INDUCE MACROPHAGE POLARIZATION INCLUDE CYTOKINES AND MICROBIAL FACTORS PRODUCED BY PATHOGENS OR COMMENSAL MICROBIOTA. SIGNALING PATHWAYS UTILIZED BY THESE POLARIZING FACTORS HAVE BEEN WELL CHARACTERIZED, BUT IT IS LESS CLEAR HOW SIGNALS ARE CONVERTED INTO COMPLEX AND SUSTAINED PATTERNS OF GENE EXPRESSION, AND HOW MACROPHAGES ARE REPROGRAMMED DURING POLARIZATION TO ALTER THEIR RESPONSES TO SUBSEQUENT ENVIRONMENTAL CHALLENGES. EMERGING EVIDENCE, REVIEWED HERE, SUGGESTS AN IMPORTANT ROLE FOR EPIGENETIC MECHANISMS IN MODULATING AND TRANSMITTING SIGNALS DURING MACROPHAGE POLARIZATION AND REPROGRAMMING. DEEPER UNDERSTANDING OF EPIGENETIC REGULATION OF MACROPHAGE PHENOTYPE WILL ENABLE DEVELOPMENT OF GENE-SPECIFIC THERAPEUTIC APPROACHES TO ENHANCE HOST DEFENSE WHILE PRESERVING TISSUE INTEGRITY AND PREVENTING CHRONIC INFLAMMATORY DISEASES. 2013 5 6395 35 THE ROLE OF THE MEDIATORS OF INFLAMMATION IN CANCER DEVELOPMENT. EPIGENETIC DISORDERS SUCH AS POINT MUTATIONS IN CELLULAR TUMOR SUPPRESSOR GENES, DNA METHYLATION AND POST-TRANSLATIONAL MODIFICATIONS ARE NEEDED TO TRANSFORMATION OF NORMAL CELLS INTO CANCER CELLS. THESE EVENTS RESULT IN ALTERATIONS IN CRITICAL PATHWAYS RESPONSIBLE FOR MAINTAINING THE NORMAL CELLULAR HOMEOSTASIS, TRIGGERING TO AN INFLAMMATORY RESPONSE WHICH CAN LEAD THE DEVELOPMENT OF CANCER. THE INFLAMMATORY RESPONSE IS A UNIVERSAL DEFENSE MECHANISM ACTIVATED IN RESPONSE TO AN INJURY TISSUE, OF ANY NATURE, THAT INVOLVES BOTH INNATE AND ADAPTIVE IMMUNE RESPONSES, THROUGH THE COLLECTIVE ACTION OF A VARIETY OF SOLUBLE MEDIATORS. MANY INFLAMMATORY SIGNALING PATHWAYS ARE ACTIVATED IN SEVERAL TYPES OF CANCER, LINKING CHRONIC INFLAMMATION TO TUMORIGENESIS PROCESS. THUS, INFLAMMATORY RESPONSES PLAY DECISIVE ROLES AT DIFFERENT STAGES OF TUMOR DEVELOPMENT, INCLUDING INITIATION, PROMOTION, GROWTH, INVASION, AND METASTASIS, AFFECTING ALSO THE IMMUNE SURVEILLANCE. IMMUNE CELLS THAT INFILTRATE TUMORS ENGAGE IN AN EXTENSIVE AND DYNAMIC CROSSTALK WITH CANCER CELLS, AND SOME OF THE MOLECULAR EVENTS THAT MEDIATE THIS DIALOG HAVE BEEN REVEALED. A RANGE OF INFLAMMATION MEDIATORS, INCLUDING CYTOKINES, CHEMOKINES, FREE RADICALS, PROSTAGLANDINS, GROWTH AND TRANSCRIPTION FACTORS, MICRORNAS, AND ENZYMES AS, CYCLOOXYGENASE AND MATRIX METALLOPROTEINASE, COLLECTIVELY ACTS TO CREATE A FAVORABLE MICROENVIRONMENT FOR THE DEVELOPMENT OF TUMORS. IN THIS REVIEW ARE PRESENTED THE MAIN MEDIATORS OF THE INFLAMMATORY RESPONSE AND DISCUSSED THE LIKELY MECHANISMS THROUGH WHICH, THEY INTERACT WITH EACH OTHER TO CREATE A CONDITION FAVORABLE TO DEVELOPMENT OF CANCER. 2015 6 6592 37 TUMOR-ASSOCIATED MACROPHAGES IN HEPATOCELLULAR CARCINOMA PATHOGENESIS, PROGNOSIS AND THERAPY. HEPATOCELLULAR CARCINOMA (HCC) CONSTITUTES A MAJOR HEALTH BURDEN GLOBALLY, AND IT IS CAUSED BY INTRINSIC GENETIC MUTATIONS ACTING IN CONCERT WITH A MULTITUDE OF EPIGENETIC AND EXTRINSIC RISK FACTORS. CANCER INDUCES MYELOPOIESIS IN THE BONE MARROW, AS WELL AS THE MOBILIZATION OF HEMATOPOIETIC STEM AND PROGENITOR CELLS, WHICH RESIDE IN THE SPLEEN. MONOCYTES PRODUCED IN THE BONE MARROW AND THE SPLEEN FURTHER INFILTRATE TUMORS, WHERE THEY DIFFERENTIATE INTO TUMOR-ASSOCIATED MACROPHAGES (TAMS). THE RELATIONSHIP BETWEEN CHRONIC INFLAMMATION AND HEPATOCARCINOGENESIS HAS BEEN THOROUGHLY INVESTIGATED OVER THE PAST DECADE; HOWEVER, SEVERAL ASPECTS OF THE ROLE OF TAMS IN HCC DEVELOPMENT ARE YET TO BE DETERMINED. IN RESPONSE TO CERTAIN STIMULI AND SIGNALING, MONOCYTES DIFFERENTIATE INTO MACROPHAGES WITH ANTITUMOR PROPERTIES, WHICH ARE CLASSIFIED AS M1-LIKE. ON THE OTHER HAND, UNDER DIFFERENT STIMULI AND SIGNALING, THE POLARIZATION OF MACROPHAGES SHIFTS TOWARDS AN M2-LIKE PHENOTYPE WITH A TUMOR PROMOTING CAPACITY. M2-LIKE MACROPHAGES DRIVE TUMOR GROWTH BOTH DIRECTLY AND INDIRECTLY, VIA THE SUPPRESSION OF CYTOTOXIC CELL POPULATIONS, INCLUDING CD8+ T CELLS AND NK CELLS. THE TUMOR MICROENVIRONMENT AFFECTS THE RESPONSE TO IMMUNOTHERAPIES. THEREFORE, AN ENHANCED UNDERSTANDING OF ITS IMMUNOBIOLOGY IS ESSENTIAL FOR THE DEVELOPMENT OF NEXT-GENERATION IMMUNOTHERAPIES. THE UTILIZATION OF VARIOUS MONOCYTE-CENTERED ANTICANCER TREATMENT MODALITIES HAS BEEN UNDER CLINICAL INVESTIGATION, SELECTIVELY TARGETING AND MODULATING THE PROCESSES OF MONOCYTE RECRUITMENT, ACTIVATION AND MIGRATION. THIS REVIEW SUMMARIZES THE CURRENT EVIDENCE ON THE ROLE OF TAMS IN HCC PATHOGENESIS AND PROGRESSION, AS WELL AS IN THEIR POTENTIAL INVOLVEMENT IN TUMOR THERAPY, SHEDDING LIGHT ON EMERGING ANTICANCER TREATMENT METHODS TARGETING MONOCYTES. 2022 7 4040 49 MACROPHAGE PLASTICITY AND POLARIZATION: IN VIVO VERITAS. DIVERSITY AND PLASTICITY ARE HALLMARKS OF CELLS OF THE MONOCYTE-MACROPHAGE LINEAGE. IN RESPONSE TO IFNS, TOLL-LIKE RECEPTOR ENGAGEMENT, OR IL-4/IL-13 SIGNALING, MACROPHAGES UNDERGO M1 (CLASSICAL) OR M2 (ALTERNATIVE) ACTIVATION, WHICH REPRESENT EXTREMES OF A CONTINUUM IN A UNIVERSE OF ACTIVATION STATES. PROGRESS HAS NOW BEEN MADE IN DEFINING THE SIGNALING PATHWAYS, TRANSCRIPTIONAL NETWORKS, AND EPIGENETIC MECHANISMS UNDERLYING M1-M2 OR M2-LIKE POLARIZED ACTIVATION. FUNCTIONAL SKEWING OF MONONUCLEAR PHAGOCYTES OCCURS IN VIVO UNDER PHYSIOLOGICAL CONDITIONS (E.G., ONTOGENESIS AND PREGNANCY) AND IN PATHOLOGY (ALLERGIC AND CHRONIC INFLAMMATION, TISSUE REPAIR, INFECTION, AND CANCER). HOWEVER, IN SELECTED PRECLINICAL AND CLINICAL CONDITIONS, COEXISTENCE OF CELLS IN DIFFERENT ACTIVATION STATES AND UNIQUE OR MIXED PHENOTYPES HAVE BEEN OBSERVED, A REFLECTION OF DYNAMIC CHANGES AND COMPLEX TISSUE-DERIVED SIGNALS. THE IDENTIFICATION OF MECHANISMS AND MOLECULES ASSOCIATED WITH MACROPHAGE PLASTICITY AND POLARIZED ACTIVATION PROVIDES A BASIS FOR MACROPHAGE-CENTERED DIAGNOSTIC AND THERAPEUTIC STRATEGIES. 2012 8 2344 26 EPIGENETIC REGULATION OF MACROPHAGES: FROM HOMEOSTASIS MAINTENANCE TO HOST DEFENSE. MACROPHAGES ARE CRUCIAL MEMBERS OF THE INNATE IMMUNE RESPONSE AND IMPORTANT REGULATORS. THE DIFFERENTIATION AND ACTIVATION OF MACROPHAGES REQUIRE THE TIMELY REGULATION OF GENE EXPRESSION, WHICH DEPENDS ON THE INTERACTION OF A VARIETY OF FACTORS, INCLUDING TRANSCRIPTION FACTORS AND EPIGENETIC MODIFICATIONS. EPIGENETIC CHANGES ALSO GIVE MACROPHAGES THE ABILITY TO SWITCH RAPIDLY BETWEEN CELLULAR PROGRAMS, INDICATING THE ABILITY OF EPIGENETIC MECHANISMS TO AFFECT PHENOTYPE PLASTICITY. IN THIS REVIEW, WE FOCUS ON KEY EPIGENETIC EVENTS ASSOCIATED WITH MACROPHAGE FATE, HIGHLIGHTING EVENTS RELATED TO THE MAINTENANCE OF TISSUE HOMEOSTASIS, RESPONSES TO DIFFERENT STIMULI AND THE FORMATION OF INNATE IMMUNE MEMORY. FURTHER UNDERSTANDING OF THE EPIGENETIC REGULATION OF MACROPHAGES WILL BE HELPFUL FOR MAINTAINING TISSUE INTEGRITY, PREVENTING CHRONIC INFLAMMATORY DISEASES AND DEVELOPING THERAPIES TO ENHANCE HOST DEFENSE. 2020 9 1232 30 CROSSTALK BETWEEN INFLAMMATORY SIGNALING AND METHYLATION IN CANCER. INFLAMMATION IS AN INTRICATE IMMUNE RESPONSE AGAINST INFECTION AND TISSUE DAMAGE. WHILE THE INITIAL IMMUNE RESPONSE IS IMPORTANT FOR PREVENTING TUMORIGENESIS, CHRONIC INFLAMMATION IS IMPLICATED IN CANCER PATHOGENESIS. IT HAS BEEN LINKED TO VARIOUS STAGES OF TUMOR DEVELOPMENT INCLUDING TRANSFORMATION, PROLIFERATION, ANGIOGENESIS, AND METASTASIS. IMMUNE CELLS, THROUGH THE PRODUCTION OF INFLAMMATORY MEDIATORS SUCH AS CYTOKINES, CHEMOKINES, TRANSFORMING GROWTH FACTORS, AND ADHESION MOLECULES CONTRIBUTE TO THE SURVIVAL, GROWTH, AND PROGRESSION OF THE TUMOR IN ITS MICROENVIRONMENT. THE ABERRANT EXPRESSION AND SECRETION OF PRO-INFLAMMATORY AND GROWTH FACTORS BY THE TUMOR CELLS RESULT IN THE RECRUITMENT OF IMMUNE CELLS, THUS CREATING A MUTUAL CROSSTALK. THE RECIPROCAL SIGNALING BETWEEN THE TUMOR CELLS AND THE IMMUNE CELLS CREATES AND MAINTAINS A SUCCESSFUL TUMOR NICHE. MANY INFLAMMATORY FACTORS ARE REGULATED BY EPIGENETIC MECHANISMS INCLUDING DNA METHYLATION AND HISTONE MODIFICATIONS. IN PARTICULAR, DNA AND HISTONE METHYLATION ARE CRUCIAL FORMS OF TRANSCRIPTIONAL REGULATION AND ABERRANT METHYLATION HAS BEEN ASSOCIATED WITH DEREGULATED GENE EXPRESSION IN ONCOGENESIS. SUCH DEREGULATIONS HAVE BEEN REPORTED IN BOTH SOLID TUMORS AND HEMATOLOGICAL MALIGNANCIES. WITH TECHNOLOGICAL ADVANCEMENTS TO STUDY GENOME-WIDE EPIGENETIC LANDSCAPES, IT IS NOW POSSIBLE TO IDENTIFY MOLECULAR MECHANISMS UNDERLYING ALTERED INFLAMMATORY PROFILES IN CANCER. IN THIS REVIEW, WE DISCUSS THE ROLE OF DNA AND HISTONE METHYLATION IN REGULATION OF INFLAMMATORY PATHWAYS IN HUMAN CANCERS AND REVIEW THE MERITS AND CHALLENGES OF TARGETING INFLAMMATORY MEDIATORS AS WELL AS EPIGENETIC REGULATORS IN CANCER. 2021 10 928 26 CHRONIC INFLAMMATION, THE TUMOR MICROENVIRONMENT AND CARCINOGENESIS. CHRONIC INFLAMMATION OFTEN PRECEDES OR ACCOMPANIES A SUBSTANTIAL NUMBER OF CANCERS. INDEED, ANTI-INFLAMMATORY THERAPIES HAVE SHOWN EFFICACY IN CANCER PREVENTION AND TREATMENT. THE EXACT MECHANISMS THAT TURN A WOUND HEALING PROCESS INTO A CANCER PRECURSOR ARE TOPICS OF INTENSE RESEARCH. A PATHOGENIC LINK HAS BEEN IDENTIFIED BETWEEN INFLAMMATORY MEDIATORS, INFLAMMATION RELATED GENE POLYMORPHISMS AND CARCINOGENESIS. ANIMAL MODELS OF CANCER HAVE BEEN INSTRUMENTAL IN DEMONSTRATING THE DIVERSITY OF MECHANISMS THROUGH WHICH EVERY TUMOR COMPARTMENT AND TUMOR STAGE MAY BE AFFECTED BY THE UNDERLYING INFLAMMATORY PROCESS. IN THIS REVIEW, WE FOCUS ON THE INTERACTION BETWEEN CHRONIC INFLAMMATION, TUMOR STEM CELLS AND THE TUMOR MICROENVIRONMENT. WE SUMMARIZE THE PROPOSED MECHANISMS THAT LEAD TO THE RECRUITMENT OF BONE MARROW DERIVED CELLS AND EXPLORE THE GENETIC AND EPIGENETIC ALTERATIONS THAT MAY OCCUR IN INFLAMMATION ASSOCIATED CANCERS. 2009 11 4043 31 MACROPHAGES IN CHRONIC LIVER FAILURE: DIVERSITY, PLASTICITY AND THERAPEUTIC TARGETING. CHRONIC LIVER INJURY RESULTS IN IMMUNE-DRIVEN PROGRESSIVE FIBROSIS, WITH RISK OF CIRRHOSIS DEVELOPMENT AND IMPACT ON MORBIDITY AND MORTALITY. PERSISTENT LIVER CELL DAMAGE AND DEATH CAUSES IMMUNE CELL ACTIVATION AND INFLAMMATION. PATIENTS WITH ADVANCED CIRRHOSIS ADDITIONALLY EXPERIENCE PATHOLOGICAL BACTERIAL TRANSLOCATION, EXPOSURE TO MICROBIAL PRODUCTS AND CHRONIC ENGAGEMENT OF THE IMMUNE SYSTEM. BACTERIAL INFECTIONS HAVE A HIGH INCIDENCE IN CIRRHOSIS, WITH SPONTANEOUS BACTERIAL PERITONITIS BEING THE MOST COMMON, WHILE THE SUBSEQUENT SYSTEMIC INFLAMMATION, ORGAN FAILURE AND IMMUNE DYSREGULATION INCREASE THE MORTALITY RISK. TISSUE-RESIDENT AND RECRUITED MACROPHAGES PLAY A CENTRAL PART IN THE DEVELOPMENT OF INFLAMMATION AND FIBROSIS PROGRESSION. IN THE LIVER, ADIPOSE TISSUE, PERITONEUM AND INTESTINES, DIVERSE MACROPHAGE POPULATIONS EXHIBIT GREAT PHENOTYPIC AND FUNCTIONAL PLASTICITY DETERMINED BY THEIR ONTOGENY, EPIGENETIC PROGRAMMING AND LOCAL MICROENVIRONMENT. THESE CHANGES CAN, AT DIFFERENT TIMES, PROMOTE OR AMELIORATE DISEASE STATES AND THEREFORE REPRESENT POTENTIAL TARGETS FOR MACROPHAGE-DIRECTED THERAPIES. IN THIS REVIEW, WE DISCUSS THE EVIDENCE FOR MACROPHAGE PHENOTYPIC AND FUNCTIONAL ALTERATIONS IN TISSUE COMPARTMENTS DURING THE DEVELOPMENT AND PROGRESSION OF CHRONIC LIVER FAILURE IN DIFFERENT AETIOLOGIES AND HIGHLIGHT THE POTENTIAL OF MACROPHAGE MODULATION AS A THERAPEUTIC STRATEGY FOR LIVER DISEASE. 2021 12 862 32 CHROMATIN REMODELING IN MONOCYTE AND MACROPHAGE ACTIVATION. INCREASING EVIDENCE COLLECTED DURING THE LAST YEARS SUPPORTS THE IDEA THAT MONOCYTE AND MACROPHAGE ACTIVATION IS NOT ONLY ASSOCIATED WITH TRANSCRIPTIONAL CHANGES BUT ALSO CHANGES IN THE CHROMATIN LANDSCAPE. MOREOVER, THE INTRODUCTION OF A MULTIDIMENSIONAL MODEL OF MACROPHAGE ACTIVATION ALLOWS A MORE PRECISE DESCRIPTION OF MONOCYTES AND MACROPHAGES UNDER HOMEOSTATIC AND PATHOPHYSIOLOGICAL CONDITIONS. MONOCYTES AND MACROPHAGES ARE MASTERS OF INTEGRATING MICROENVIRONMENTAL SIGNALS, THEREBY RESHAPING THEIR CHROMATIN LANDSCAPE AND AS A CONSEQUENCE THEIR TRANSCRIPTIONAL AND FUNCTIONAL PROGRAMS. ALBEIT THESE CELLS SHARE A LARGE NUMBER OF EPIGENETIC LANDMARKS, THEIR CHROMATIN IS SIGNIFICANTLY SHAPED BY ENVIRONMENTAL SIGNALS. THE CHROMATIN LANDSCAPE OF ANY GIVEN TISSUE MACROPHAGE IS A RATHER SPECIFIC FINGERPRINT OF THESE CELLS, WHICH IS DIRECTLY LINKED TO TISSUE-SPECIFIC FUNCTIONS OF THESE CELLS. MOREOVER, CHROMATIN REMODELING IN RESPONSE TO STRESS SIGNALS ALSO SEEMS TO BE AN IMPORTANT MECHANISM OF THESE CELLS TO INCREASE THEIR READINESS FOR FUTURE STRESSORS. UNDERSTANDING THIS SOPHISTICATED EPIGENETIC REGULATORY NETWORK IN MONOCYTES AND MACROPHAGES WILL OPEN UP NEW AVENUES TOWARD TISSUE- AND DISEASE-SPECIFIC THERAPEUTIC STRATEGIES IN MANY OF THE CHRONIC INFLAMMATORY DISEASES OUR SOCIETIES ARE CURRENTLY FACING. 2017 13 4738 35 NOVEL FIBROBLAST PHENOTYPES IN HOMEOSTASIS AND CHRONIC INFLAMMATION: FROM FUNCTIONS TO POTENTIAL REGULATORS. FIBROBLASTS ARE ESSENTIAL COMPONENTS OF THE STROMA, SUSTAINING A VARIETY OF TISSUES AND BEING KEY TO THE PROCESS OF TISSUE REPAIR AFTER INJURY. THEIR ROLE IN TISSUE REPAIR HAS BEEN ATTRIBUTED TO THEIR ABILITY TO ACQUIRE A CONTRACTILE, EXTRACELLULAR MATRIX-PRODUCING PHENOTYPE KNOWN AS MYOFIBROBLASTS. THIS PROPERTY IS PRIMARILY DEPENDENT ON THEIR RESPONSE TO THE PLEIOTROPIC CYTOKINE TRANSFORMING GROWTH FACTOR-BETA1. UNTIL RECENTLY, THE POTENTIAL ROLE OF FIBROBLASTS IN OTHER HOMEOSTATIC AND DISEASE-RELATED PROCESSES WAS LESS WELL UNDERSTOOD. ALTHOUGH IN VITRO STUDIES INDICATED THAT FIBROBLASTS ARE ABLE TO RESPOND TO AND SECRETE INFLAMMATORY MEDIATORS, DEFINITIVE EVIDENCE OF THEIR CONTRIBUTION TO CHRONIC INFLAMMATION WAS LIMITED. HOWEVER, THE EMERGENCE OF TECHNIQUES THAT ALLOW EXPLORATION OF TISSUES AT THE SINGLE CELL LEVEL HAS CHALLENGED THE PREVIOUS PARADIGMS ON FIBROBLAST IDENTITY AND FUNCTIONS, AND HAS LED TO THE DISCOVERY OF SIGNIFICANT DIVERSITY, SHOWING THE PRESENCE OF FIBROBLASTS WITH ALTERNATE TRANSCRIPTIONAL PROFILES IN A VARIETY OF TISSUES. THESE STUDIES HAVE ALSO SUGGESTED POTENTIAL ROLES OF NOVEL FIBROBLAST SUBTYPES AS REGULATORS OF EPITHELIAL HOMEOSTASIS AND RENEWAL, INFLAMMATORY CELL INFILTRATION AND ACTIVATION, AND ANTIGEN PRESENTATION. HERE, WE PROVIDE A COMPREHENSIVE REVIEW OF THE RECENT LITERATURE ON FIBROBLAST DIVERSITY IN THE DIGESTIVE TRACT, SKIN, LUNGS AND JOINTS. WE ALSO REVIEW EVIDENCE OF THEIR CONTRIBUTION TO THE REGULATION OF HOMEOSTASIS AND CHRONIC INFLAMMATION, AS WELL AS THEIR INTERACTIONS WITH OTHER CELLS IN VARIOUS TISSUE COMPARTMENTS. WE DISCUSS EVIDENCE OF DIFFERENT FACTORS INVOLVED IN THE CONTROL OF FIBROBLAST FUNCTION, ADDRESSING THE ROLE OF VARIOUS CYTOKINES, TRANSCRIPTION FACTORS AND EPIGENETIC CHANGES, AS WELL AS MICROENVIRONMENTAL FACTORS, INCLUDING EXTRACELLULAR MATRIX STIFFNESS, HYPOXIA, AND METABOLIC SHIFTS. 2023 14 2036 27 EPIGENETIC CHANGES OF THE IMMUNE SYSTEM WITH ROLE IN TUMOR DEVELOPMENT. TUMOR DEVELOPMENT IS CLOSELY RELATED TO CHRONIC INFLAMMATION AND TO EVASION OF IMMUNE DEFENSE MECHANISMS BY NEOPLASTIC CELLS. THE MEDIATORS OF THE INFLAMMATORY PROCESS AS WELL AS PROTEINS INVOLVED IN IMMUNE RESPONSE OR IMMUNE RESPONSE EVASION CAN BE SUBJECT TO VARIOUS EPIGENETIC CHANGES SUCH AS METHYLATION, ACETYLATION, OR PHOSPHORYLATION. SOME OF THESE, SUCH AS CYTOKINE SUPPRESSORS, ARE UNDERGOING REPRESSION THROUGH EPIGENETIC CHANGES, AND OTHERS SUCH AS CYTOKINES OR CHEMOKINES ARE UNDERGOING ACTIVATION THROUGH EPIGENETIC CHANGES, BOTH MODIFICATIONS HAVING AS A RESULT TUMOR PROGRESSION. THE ACTIVATING CHANGES CAN AFFECT THE RECEPTOR MOLECULES INVOLVED IN IMMUNE RESPONSE AND THESE PROMOTE INFLAMMATION AND SUBSEQUENTLY TUMOR DEVELOPMENT WHILE THE INACTIVATING CHANGES SEEM TO BE RELATED TO THE TUMOR REGRESSION PROCESS. THE PROTEINS INVOLVED IN ANTIGEN PRESENTATION, AND, THEREFORE IN IMMUNE RESPONSE ESCAPE, SUCH AS CLASSICAL HLA PROTEINS AND RELATED APM (ANTIGEN PRESENTATION MACHINERY) WITH THEIR EPIGENETIC CHANGES CONTRIBUTE TO THE TUMOR DEVELOPMENT PROCESS, EITHER TO TUMOR PROGRESSION OR REGRESSION, DEPENDING ON THE IMMUNE EFFECTOR CELLS THAT ARE IN PLAY. 2018 15 3672 22 INFLAMMATION AND CANCER: AN ANCIENT LINK WITH NOVEL POTENTIALS. INFECTION AND CHRONIC INFLAMMATION CONTRIBUTE TO ABOUT 1 IN 4 OF ALL CANCER CASES. MEDIATORS OF THE INFLAMMATORY RESPONSE, E.G., CYTOKINES, FREE RADICALS, PROSTAGLANDINS AND GROWTH FACTORS, CAN INDUCE GENETIC AND EPIGENETIC CHANGES INCLUDING POINT MUTATIONS IN TUMOR SUPPRESSOR GENES, DNA METHYLATION AND POST-TRANSLATIONAL MODIFICATIONS, CAUSING ALTERATIONS IN CRITICAL PATHWAYS RESPONSIBLE FOR MAINTAINING THE NORMAL CELLULAR HOMEOSTASIS AND LEADING TO THE DEVELOPMENT AND PROGRESSION OF CANCER. RECENT DISCOVERY OF AN INTERACTION BETWEEN MICRORNAS AND INNATE IMMUNITY DURING INFLAMMATION HAS FURTHER STRENGTHENED THE ASSOCIATION BETWEEN INFLAMMATION AND CANCER. 2007 16 5931 31 TARGETING EPIGENETIC MODIFIERS TO REPROGRAMME MACROPHAGES IN NON-RESOLVING INFLAMMATION-DRIVEN ATHEROSCLEROSIS. EPIGENOMIC AND EPIGENETIC RESEARCH HAS BEEN PROVIDING SEVERAL NEW INSIGHTS INTO A VARIETY OF DISEASES CAUSED BY NON-RESOLVING INFLAMMATION, INCLUDING CARDIOVASCULAR DISEASES. ATHEROSCLEROSIS (AS) HAS LONG BEEN RECOGNIZED AS A CHRONIC INFLAMMATORY DISEASE OF THE ARTERIAL WALLS, CHARACTERIZED BY LOCAL PERSISTENT AND STEPWISE ACCELERATING INFLAMMATION WITHOUT RESOLUTION, ALSO KNOWN AS UNCONTROLLED INFLAMMATION. THE PATHOGENESIS OF AS IS DRIVEN PRIMARILY BY HIGHLY PLASTIC MACROPHAGES VIA THEIR POLARIZATION TO PRO- OR ANTI-INFLAMMATORY PHENOTYPES AS WELL AS OTHER NOVEL SUBTYPES RECENTLY IDENTIFIED BY SINGLE-CELL SEQUENCING. ALTHOUGH EMERGING EVIDENCE HAS INDICATED THE KEY ROLE OF THE EPIGENETIC MACHINERY IN THE REGULATION OF MACROPHAGE PLASTICITY, THE INVESTIGATION OF EPIGENETIC ALTERATIONS AND MODIFIERS IN AS AND RELATED INFLAMMATION IS STILL IN ITS INFANCY. AN INCREASING NUMBER OF THE EPIGENETIC MODIFIERS (E.G. TET2, DNMT3A, HDAC3, HDAC9, JMJD3, KDM4A) HAVE BEEN IDENTIFIED IN EPIGENETIC REMODELLING OF MACROPHAGES THROUGH DNA METHYLATION OR HISTONE MODIFICATIONS (E.G. METHYLATION, ACETYLATION, AND RECENTLY LACTYLATION) IN INFLAMMATION. THESE OR MANY UNEXPLORED MODIFIERS FUNCTION TO DETERMINE OR SWITCH THE DIRECTION OF MACROPHAGE POLARIZATION VIA TRANSCRIPTIONAL REPROGRAMMING OF GENE EXPRESSION AND INTRACELLULAR METABOLIC REWIRING UPON MICROENVIRONMENTAL CUES, THEREBY REPRESENTING A PROMISING TARGET FOR ANTI-INFLAMMATORY THERAPY IN AS. HERE, WE REVIEW UP-TO-DATE FINDINGS INVOLVING THE EPIGENETIC REGULATION OF MACROPHAGES TO SHED LIGHT ON THE MECHANISM OF UNCONTROLLED INFLAMMATION DURING AS ONSET AND PROGRESSION. WE ALSO DISCUSS CURRENT CHALLENGES FOR DEVELOPING AN EFFECTIVE AND SAFE ANTI-AS THERAPY THAT TARGETS THE EPIGENETIC MODIFIERS AND PROPOSE A POTENTIAL ANTI-INFLAMMATORY STRATEGY THAT REPOLARIZES MACROPHAGES FROM PRO- TO ANTI-INFLAMMATORY PHENOTYPES. 2021 17 4200 33 METABOLIC REQUIREMENTS OF TH17 CELLS AND OF B CELLS: REGULATION AND DEFECTS IN HEALTH AND IN INFLAMMATORY DISEASES. THE IMMUNE SYSTEM PROTECTS FROM INFECTIONS AND CANCER THROUGH COMPLEX CELLULAR NETWORKS. FOR THIS PURPOSE, IMMUNE CELLS REQUIRE WELL-DEVELOPED MECHANISMS OF ENERGY GENERATION. HOWEVER, THE IMMUNE SYSTEM ITSELF CAN ALSO CAUSE DISEASES WHEN DEFECTIVE REGULATION RESULTS IN THE EMERGENCE OF AUTOREACTIVE LYMPHOCYTES. RECENT STUDIES PROVIDE INSIGHTS INTO HOW DIFFERENTIAL PATTERNS OF IMMUNE CELL RESPONSES ARE ASSOCIATED WITH SELECTIVE METABOLIC PATHWAYS. THIS REVIEW WILL EXAMINE THE CHANGING METABOLIC REQUIREMENTS OF TH17 CELLS AND OF B CELLS AT DIFFERENT STAGES OF THEIR DEVELOPMENT AND ACTIVATION. BOTH CELLS PROVIDE PROTECTION BUT CAN ALSO MEDIATE DISEASES THROUGH THE PRODUCTION OF AUTOANTIBODIES AND THE PRODUCTION OF PROINFLAMMATORY MEDIATORS. IN HEALTH, B CELLS PRODUCE ANTIBODIES AND CYTOKINES AND PRESENT ANTIGENS TO T CELLS TO MOUNT SPECIFIC IMMUNITY. TH17 CELLS, ON THE OTHER HAND, PROVIDE PROTECTION AGAINST EXTRA CELLULAR PATHOGENS AT MUCOSAL SURFACES BUT CAN ALSO DRIVE CHRONIC INFLAMMATION. THE LATTER CELLS CAN ALSO PROMOTE THE DIFFERENTIATION OF B CELLS TO PLASMA CELLS TO PRODUCE MORE AUTOANTIBODIES. METABOLISM-REGULATED CHECKPOINTS AT DIFFERENT STAGES OF THEIR DEVELOPMENT ENSURE THE THAT SELF-REACTIVE B CELLS CLONES AND NEEDLESS PRODUCTION OF INTERLEUKIN (IL-)17 ARE LIMITED. THE METABOLIC REGULATION OF THE TWO CELL TYPES HAS SOME SIMILARITIES, E.G. THE UTILITY OF HYPOXIA INDUCED FACTOR (HIF)1ALPHA DURING LOW OXYGEN TENSION, TO PREVENT AUTOIMMUNITY AND REGULATE INFLAMMATION. THERE ARE ALSO CLEAR DIFFERENCES, AS TH17 CELLS ONLY ARE VULNERABLE TO THE LACK OF CERTAIN AMINO ACIDS. B CELLS, UNLIKE TH17 CELLS, ARE ALSO DEPENDENT OF MECHANISTIC TARGET OF RAPAMYCIN 2 (MTORC2) TO FUNCTION. SIGNIFICANT KNOWLEDGE HAS RECENTLY BEEN GAINED, PARTICULARLY ON TH17 CELLS, ON HOW METABOLISM REGULATES THESE CELLS THROUGH INFLUENCING THEIR EPIGENOME. METABOLIC DYSREGULATION OF TH17 CELLS AND B CELLS CAN LEAD TO CHRONIC INFLAMMATION. DISEASE ASSOCIATED ALTERATIONS IN THE GENOME CAN, IN ADDITION, CAUSE DYSREGULATION TO METABOLISM AND, THEREBY, RESULT IN EPIGENETIC ALTERATIONS IN THESE CELLS. RECENT STUDIES HIGHLIGHT HOW PATHOLOGY CAN RESULT FROM THE COOPERATION BETWEEN THE TWO CELL TYPES BUT ONLY FEW HAVE SO FAR ADDRESSED THE KEY METABOLIC ALTERATIONS IN SUCH SETTINGS. KNOWLEDGE OF THE IMPACT OF METABOLIC DYSFUNCTION ON CHRONIC INFLAMMATION AND PATHOLOGY CAN REVEAL NOVEL THERAPEUTIC TARGETS TO TREAT SUCH DISEASES. 2022 18 2335 26 EPIGENETIC REGULATION OF INFLAMMATORY CYTOKINES AND ASSOCIATED GENES IN HUMAN MALIGNANCIES. INFLAMMATION IS A MULTIFACETED DEFENSE RESPONSE OF IMMUNE SYSTEM AGAINST INFECTION. CHRONIC INFLAMMATION HAS BEEN IMPLICATED AS AN IMMINENT THREAT FOR MAJOR HUMAN MALIGNANCIES AND IS DIRECTLY LINKED TO VARIOUS STEPS INVOLVED IN TUMORIGENESIS. INFLAMMATORY CYTOKINES, INTERLEUKINS, INTERFERONS, TRANSFORMING GROWTH FACTORS, CHEMOKINES, AND ADHESION MOLECULES HAVE BEEN ASSOCIATED WITH CHRONIC INFLAMMATION. NUMEROUS CYTOKINES ARE REPORTED TO BE ABERRANTLY REGULATED BY DIFFERENT EPIGENETIC MECHANISMS LIKE DNA METHYLATION AND HISTONE MODIFICATIONS IN TUMOR TISSUES, CONTRIBUTING TO PATHOGENESIS OF TUMOR IN MULTIPLE WAYS. SOME OF THESE CYTOKINES ALSO WORK AS EPIGENETIC REGULATORS OF OTHER CRUCIAL GENES IN TUMOR BIOLOGY, EITHER DIRECTLY OR INDIRECTLY. SUCH REGULATIONS ARE REPORTED IN LUNG, BREAST, CERVICAL, GASTRIC, COLORECTAL, PANCREATIC, PROSTATE, AND HEAD AND NECK CANCERS. EPIGENETICS OF INFLAMMATORY MEDIATORS IN CANCER IS CURRENTLY SUBJECT OF EXTENSIVE RESEARCH. THESE INVESTIGATIONS MAY HELP IN UNDERSTANDING CANCER BIOLOGY AND TO DEVELOP EFFECTIVE THERAPEUTIC STRATEGIES. THE PURPOSE OF THIS PAPER IS TO HAVE A BRIEF VIEW OF THE ABERRANT REGULATION OF INFLAMMATORY CYTOKINES IN HUMAN MALIGNANCIES. 2015 19 1864 30 EMERGING AVENUES LINKING INFLAMMATION AND CANCER. THE ROLE OF INFLAMMATION IN CARCINOGENESIS HAS BEEN EXTENSIVELY INVESTIGATED AND WELL DOCUMENTED. MANY BIOCHEMICAL PROCESSES THAT ARE ALTERED DURING CHRONIC INFLAMMATION HAVE BEEN IMPLICATED IN TUMORIGENESIS. THESE INCLUDE SHIFTING CELLULAR REDOX BALANCE TOWARD OXIDATIVE STRESS; INDUCTION OF GENOMIC INSTABILITY; INCREASED DNA DAMAGE; STIMULATION OF CELL PROLIFERATION, METASTASIS, AND ANGIOGENESIS; DEREGULATION OF CELLULAR EPIGENETIC CONTROL OF GENE EXPRESSION; AND INAPPROPRIATE EPITHELIAL-TO-MESENCHYMAL TRANSITION. A WIDE ARRAY OF PROINFLAMMATORY CYTOKINES, PROSTAGLANDINS, NITRIC OXIDE, AND MATRICELLULAR PROTEINS ARE CLOSELY INVOLVED IN PREMALIGNANT AND MALIGNANT CONVERSION OF CELLS IN A BACKGROUND OF CHRONIC INFLAMMATION. INAPPROPRIATE TRANSCRIPTION OF GENES ENCODING INFLAMMATORY MEDIATORS, SURVIVAL FACTORS, AND ANGIOGENIC AND METASTATIC PROTEINS IS THE KEY MOLECULAR EVENT IN LINKING INFLAMMATION AND CANCER. ABERRANT CELL SIGNALING PATHWAYS COMPRISING VARIOUS KINASES AND THEIR DOWNSTREAM TRANSCRIPTION FACTORS HAVE BEEN IDENTIFIED AS THE MAJOR CONTRIBUTORS IN ABNORMAL GENE EXPRESSION ASSOCIATED WITH INFLAMMATION-DRIVEN CARCINOGENESIS. THE POSTTRANSCRIPTIONAL REGULATION OF GENE EXPRESSION BY MICRORNAS ALSO PROVIDES THE MOLECULAR BASIS FOR LINKING INFLAMMATION TO CANCER. THIS REVIEW HIGHLIGHTS THE MULTIFACETED ROLE OF INFLAMMATION IN CARCINOGENESIS IN THE CONTEXT OF ALTERED CELLULAR REDOX SIGNALING. 2012 20 2897 24 GASTRIC TUMOR MICROENVIRONMENT. A COMPELLING BODY OF EVIDENCE HAS DEMONSTRATED THAT GASTRIC CANCER HAS A VERY PARTICULAR TUMOR MICROENVIRONMENT, A SIGNATURE VERY SUITABLE TO PROMOTE TUMOR PROGRESSION AND METASTASIS. RECENT INVESTIGATIONS HAVE PROVIDED NEW INSIGHTS INTO THE MULTIPLE MOLECULAR MECHANISMS, DEFINED BY GENETIC AND EPIGENETIC MECHANISMS, SUPPORTING A VERY ACTIVE CROSS TALK BETWEEN THE COMPONENTS OF THE TUMOR MICROENVIRONMENT AND THUS DEFINING THE FATE OF TUMOR PROGRESSION. IN THIS REVIEW, WE INTEND TO HIGHLIGHT THE ROLE OF VERY ACTIVE CONTRIBUTORS AT GASTRIC CANCER TME, PARTICULARLY CANCER-ASSOCIATED FIBROBLASTS, BONE MARROW-DERIVED CELLS, TUMOR-ASSOCIATED MACROPHAGES, AND TUMOR-INFILTRATING NEUTROPHILS, ALL OF THEM SURROUNDED BY AN OVERTIME CHANGING EXTRACELLULAR MATRIX. IN ADDITION, THE VERY ACTIVE CROSS TALK BETWEEN THE COMPONENTS OF THE TUMOR MICROENVIRONMENT, DEFINED BY GENETIC AND EPIGENETIC MECHANISMS, THUS DEFINING THE FATE OF TUMOR PROGRESSION, IS ALSO REVIEWED. 2020