1 6263 125 THE MULTIPLE WAYS WNT SIGNALING CONTRIBUTES TO ACUTE LEUKEMIA PATHOGENESIS. WNT PROTEINS CONSTITUTE A VERY CONSERVED FAMILY OF SECRETED GLYCOPROTEINS THAT ACT AS SHORT-RANGE LIGANDS FOR SIGNALING WITH CRITICAL ROLES IN HEMATOPOIESIS, EMBRYONIC DEVELOPMENT, AND TISSUE HOMEOSTASIS. THESE PROTEINS TRANSDUCE SIGNALS VIA THE CANONICAL PATHWAY, WHICH IS BETA-CATENIN-MEDIATED AND BETTER-CHARACTERIZED, OR VIA MORE DIVERSE NONCANONICAL PATHWAYS THAT ARE BETA-CATENIN INDEPENDENT AND COMPRISE THE PLANAR CELL POLARITY (PCP) PATHWAY AND THE WNT/CA(++) PATHWAYS. SEVERAL PROTEINS REGULATE WNT SIGNALING THROUGH A VARIETY OF SOPHISTICATED MECHANISMS. DISORDERS WITHIN THE PATHWAY CAN CONTRIBUTE TO VARIOUS HUMAN DISEASES, AND THE DYSREGULATION OF WNT PATHWAYS BY DIFFERENT MOLECULAR MECHANISMS IS IMPLICATED IN THE PATHOGENESIS OF MANY TYPES OF CANCER, INCLUDING THE HEMATOLOGICAL MALIGNANCIES. THE TYPES OF LEUKEMIA DIFFER CONSIDERABLY AND CAN BE SUBDIVIDED INTO CHRONIC, MYELOID OR LYMPHOCYTIC, AND ACUTE, MYELOID OR LYMPHOCYTIC, LEUKEMIA, ACCORDING TO THE DIFFERENTIATION STAGE OF THE PREDOMINANT CELLS, THE PROGENITOR LINEAGE, THE DIAGNOSTIC AGE STRATA, AND THE SPECIFIC MOLECULAR DRIVERS BEHIND THEIR DEVELOPMENT. HERE, WE REVIEW THE ROLE OF WNT SIGNALING IN NORMAL HEMATOPOIESIS AND DISCUSS IN DETAIL THE MULTIPLE WAYS CANONICAL WNT SIGNALING CAN BE DYSREGULATED IN ACUTE LEUKEMIA, INCLUDING ALTERATIONS IN GENE EXPRESSION AND PROTEIN LEVELS, EPIGENETIC REGULATION, AND MUTATIONS. FURTHERMORE, WE HIGHLIGHT THE DIFFERENT IMPACTS OF THESE ALTERATIONS, CONSIDERING THE DISTINCT FORMS OF THE DISEASE, AND THE THERAPEUTIC POTENTIAL OF TARGETING WNT SIGNALING. 2020 2 6371 47 THE ROLE OF MICRORNAS IN THE PATHOGENESIS AND TREATMENT OF HEMATOPOIETIC MALIGNANCIES. MICRORNAS (MIRNAS) COMPRISE A RECENTLY DISCOVERED CLASS OF NON-CODING RNAS WITH REGULATORY FUNCTIONS IN POST-TRANSCRIPTIONAL GENE EXPRESSION CONTROL. MANY MIRNAS ARE LOCATED IN GENOMIC REGIONS THAT ARE FREQUENTLY DELETED IN CANCER, OR ARE SUBJECT TO EPIGENETIC AND TRANSCRIPTIONAL DEREGULATION IN CANCER CELLS. THE MIRNA TRANSCRIPTOME OF CANCER CELLS IS VERY DIFFERENT FROM THAT OF THEIR NORMAL CELL COUNTERPARTS. MIRNAS CAN EXHIBIT ONCOGENIC OR TUMOR SUPPRESSIVE OR EVEN BOTH PROPERTIES DEPENDING ON THE SPECIFIC TARGETS AND CELLULAR CONTEXT. IT IS BECOMING INCREASINGLY CLEAR THAT MIRNAS NOT ONLY SERVE AS USEFUL TUMOR BIOMARKERS WITH IMPLICATIONS FOR DIAGNOSIS, PROGNOSIS AND THE PREDICTION OF TREATMENT RESPONSES, BUT MAY ALSO BE USED FOR TARGETED CANCER TREATMENT AND EVEN AS THERAPEUTICS. IN THIS REVIEW, WE PROVIDE AN OVERVIEW OF RECENT ADVANCES IN OUR UNDERSTANDING OF THE TUMOR SUPPRESSOR MIRNAS AND ONCOMIRS INVOLVED IN THE PATHOGENESIS OF LEUKEMIAS AND LYMPHOMAS, AND THEIR TARGET TRANSCRIPTS IN CANCER SIGNALING NETWORKS. IN PARTICULAR, WE FOCUS ON THE ROLE OF MIRNAS IN CHRONIC LYMPHOCYTIC AND ACUTE LYMPHOBLASTIC LEUKEMIA AND IN B-CELL LYMPHOMAS. IN THE SECOND PART, WE REVIEW THE VARIOUS ALTERNATIVE STRATEGIES OF TARGETING MIRNAS IN CANCER THERAPY. METHODS OF ONCOMIR ANTAGONIZATION BY ANTAGOMIRS OR LOCKED NUCLEID ACIDS ARE CONTRASTED WITH STRATEGIES THAT HARNESS THE TUMOR SUPPRESSIVE PROPERTIES OF CERTAIN MIRNAS FOR CANCER TREATMENT. PRECLINICAL PROGRESS, ALSO WITH REGARD TO DELIVERY STRATEGIES, POSSIBLE SIDE EFFECTS AND OTHER PHARMACOLOGICAL ASPECTS, IS PRESENTED ALONG WITH RESULTS FROM THE FIRST HUMAN TRIALS ASSESSING THE SAFETY AND EFFICACY OF MIRNA-TARGETING THERAPEUTICS. 2013 3 3599 44 IMPORTANCE OF EPIGENETIC CHANGES IN CANCER ETIOLOGY, PATHOGENESIS, CLINICAL PROFILING, AND TREATMENT: WHAT CAN BE LEARNED FROM HEMATOLOGIC MALIGNANCIES? EPIGENETIC ALTERATIONS REPRESENT A KEY CANCER HALLMARK, EVEN IN HEMATOLOGIC MALIGNANCIES (HMS) OR BLOOD CANCERS, WHOSE CLINICAL FEATURES DISPLAY A HIGH INTER-INDIVIDUAL VARIABILITY. EVIDENCE ACCUMULATED IN RECENT YEARS INDICATES THAT INACTIVATING DNA HYPERMETHYLATION PREFERENTIALLY TARGETS THE SUBSET OF POLYCOMB GROUP (PCG) GENES THAT ARE REGULATORS OF DEVELOPMENTAL PROCESSES. CONVERSELY, ACTIVATING DNA HYPOMETHYLATION TARGETS ONCOGENIC SIGNALING PATHWAY GENES, BUT OUTCOMES OF BOTH EVENTS LEAD IN THE OVEREXPRESSION OF ONCOGENIC SIGNALING PATHWAYS THAT CONTRIBUTE TO THE STEM-LIKE STATE OF CANCER CELLS. ON THE BASIS OF RECENT EVIDENCE FROM POPULATION-BASED, CLINICAL AND EXPERIMENTAL STUDIES, WE HYPOTHESIZE THAT FACTORS ASSOCIATED WITH RISK FOR DEVELOPING A HM, SUCH AS METABOLIC SYNDROME AND CHRONIC INFLAMMATION, TRIGGER EPIGENETIC MECHANISMS TO INCREASE THE TRANSCRIPTIONAL EXPRESSION OF ONCOGENES AND ACTIVATE ONCOGENIC SIGNALING PATHWAYS. AMONG OTHERS, SIGNALING PATHWAYS ASSOCIATED WITH SUCH RISK FACTORS INCLUDE PRO-INFLAMMATORY NUCLEAR FACTOR KAPPAB (NF-KAPPAB), AND MITOGENIC, GROWTH, AND SURVIVAL JANUS KINASE (JAK) INTRACELLULAR NON-RECEPTOR TYROSINE KINASE-TRIGGERED PATHWAYS, WHICH INCLUDE SIGNALING PATHWAYS SUCH AS TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION (STAT), RAS GTPASES/MITOGEN-ACTIVATED PROTEIN KINASES (MAPKS)/EXTRACELLULAR SIGNAL-RELATED KINASES (ERKS), PHOSPHATIDYLINOSITOL 3-KINASE (PI3K)/AKT/MAMMALIAN TARGET OF RAPAMYCIN (MTOR), AND BETA-CATENIN PATHWAYS. RECENT FINDINGS ON EPIGENETIC MECHANISMS AT WORK IN HMS AND THEIR IMPORTANCE IN THE ETIOLOGY AND PATHOGENESIS OF THESE DISEASES ARE HEREIN SUMMARIZED AND DISCUSSED. FURTHERMORE, THE ROLE OF EPIGENETIC PROCESSES IN THE DETERMINATION OF BIOLOGICAL IDENTITY, THE CONSEQUENCES FOR INTERINDIVIDUAL VARIABILITY IN DISEASE CLINICAL PROFILE, AND THE POTENTIAL OF EPIGENETIC DRUGS IN HMS ARE ALSO CONSIDERED. 2013 4 1232 42 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 5 2652 37 EPIGENOMICS OF LEUKEMIA: FROM MECHANISMS TO THERAPEUTIC APPLICATIONS. LEUKEMOGENESIS IS A MULTISTEP PROCESS IN WHICH SUCCESSIVE TRANSFORMATIONAL EVENTS ENHANCE THE ABILITY OF A CLONAL POPULATION ARISING FROM HEMATOPOIETIC PROGENITOR CELLS TO PROLIFERATE, DIFFERENTIATE AND SURVIVE. CLINICALLY AND PATHOLOGICALLY, LEUKEMIA IS SUBDIVIDED INTO FOUR MAIN CATEGORIES: CHRONIC LYMPHOCYTIC LEUKEMIA, CHRONIC MYELOID LEUKEMIA, ACUTE LYMPHOCYTIC LEUKEMIA AND ACUTE MYELOID LEUKEMIA. LEUKEMIA HAS BEEN PREVIOUSLY CONSIDERED ONLY AS A GENETIC DISEASE. HOWEVER, IN RECENT YEARS, SIGNIFICANT ADVANCES HAVE BEEN MADE IN THE ELUCIDATION OF THE LEUKEMOGENESIS-ASSOCIATED PROCESSES. THUS, WE HAVE COME TO UNDERSTAND THAT EPIGENETIC ALTERATIONS INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS AND MIRNA ARE INVOLVED IN THE PERMANENT CHANGES OF GENE EXPRESSION CONTROLLING THE LEUKEMIA PHENOTYPE. IN THIS ARTICLE, WE WILL FOCUS ON THE EPIGENETIC DEFECTS ASSOCIATED WITH LEUKEMIA AND THEIR IMPLICATIONS AS BIOMARKERS FOR DIAGNOSTIC, PROGNOSTIC AND THERAPEUTIC APPLICATIONS. 2011 6 358 37 ALTERNATIVE SPLICING IN CHRONIC MYELOID LEUKEMIA (CML): A NOVEL THERAPEUTIC TARGET? ALTHOUGH THE IMATINIB BASED THERAPY OF CHRONIC MYELOID LEUKEMIA (CML) REPRESENTS A TRIUMPH OF MEDICINE, NOT ALL PATIENTS WITH CML BENEFIT FROM THIS DRUG DUE TO THE DEVELOPMENT OF RESISTANCE AND INTOLERANCE. THE INTERRUPTION OF IMATINIB TREATMENT IS OFTEN FOLLOWED BY CLINICAL RELAPSE, SUGGESTING A FAILURE IN THE KILLING OF RESIDUAL LEUKAEMIC STEM CELLS. THERE IS NEED TO IDENTIFY ALTERNATIVE SELECTIVE MOLECULAR TARGETS FOR THIS DISEASE AND DEVELOP MORE EFFECTIVE THERAPEUTIC APPROACHES. ALTERNATIVE PRE-MRNA SPLICING (AS) IS AN EPIGENETIC PROCESS THAT GREATLY DIVERSIFIES THE REPERTOIRE OF THE TRANSCRIPTOME. AS ORCHESTRATES INTERACTIONS BETWEEN VARIOUS TYPES OF PROTEINS AND BETWEEN PROTEINS AND NUCLEIC ACIDS. CHANGES CAUSED BY INDIVIDUAL SPLICING EVENTS IN THE CELLS ARE SMALL, HOWEVER, "SPLICING PROGRAMS" TYPICALLY REACT TO THESE INDIVIDUAL CHANGES WITH CONSIDERABLE EFFECTS IN CELL PROLIFERATION, CELL SURVIVAL, AND APOPTOSIS. CURRENT EVIDENCE SUGGESTS A PIVOTAL ROLE OF AS IN LEUKEMIAS, PARTICULARLY IN MYELODISPLASTIC SYNDROME (MDS) AND CHRONIC LYMPHOCYTE LEUKEMIA (CLL). FROM THESE STUDIES AND STUDIES IN OTHER MALIGNANCES, IT IS CLEAR THAT SPLICING ABNORMALITIES PLAY A SIGNIFICANT ROLE IN MALIGNANT TRANSFORMATION. EVALUATION OF AS EVENTS IN CML CAN BE USED TO IDENTIFY NOVEL DISEASE MARKERS AND DRUGSENSITIVE TARGETS TO OVERCOME THE LIMITS OF THE SMALL MOLECULE INHIBITORS CURRENTLY USED FOR TREATING PATIENTS WITH CML. THE USE OF ABERRANT SPLICE VARIANTS AS DISEASE MARKERS HAS BEEN REPORTED, HOWEVER, LITTLE IS KNOWN ABOUT THE USE OF SPLICING ABNORMALITIES AS DRUG TARGETS IN CML. HEREIN WE DISCUSS POTENTIAL THERAPEUTIC APPROACHES THAT CAN BE USED TO TARGET SPLICING ABNORMALITIES IN CML. 2013 7 736 33 CANCER STEM CELLS--NEW APPROACH TO CANCEROGENENSIS AND TREATMENT. RECENTLY, THERE IS AN INCREASING EVIDENCE SUPPORTING THE THEORY OF CANCER STEM CELLS NOT ONLY IN LEUKEMIA BUT ALSO IN SOLID CANCER. TO DATE, THE EXISTENCE OF CANCER STEM CELLS HAS BEEN PROVEN IN ACUTE AND CHRONIC MYELOID LEUKEMIA, IN BREAST CANCER, IN BRAIN TUMORS, IN LUNG CANCER AND GASTROINTESTINAL TUMORS. THIS REVIEW IS FOCUSING ON THE RECENT DISCOVERY OF STEM CELLS IN LEUKEMIA, HUMAN BRAIN TUMORS AND BREAST CANCER. A SMALL POPULATION OF CELLS IN THE TUMOR (LESS THAN 1%) SHOWS THE POTENTIAL TO GIVE RISE TO THE TUMOR AND ITS GROWTH. THESE CELLS HAVE A SUBSTANTIAL CHARACTERISTIC OF STEM CELLS--ABILITY FOR SELF-RENEWAL WITHOUT LOSS OF PROLIFERATION CAPACITY WITH EACH CELL DIVISION. FURTHERMORE THEY ARE IMMORTAL, RATHER RESISTANT TO TREATMENT AND EXPRESS TYPICAL MARKERS OF STEM CELLS. THE ORIGIN OF THESE RESIDENT CANCER STEM CELLS IS NOT CLEAR. WHETHER THE CANCER STEM CELLS ORIGINATE FROM NORMAL STEM CELLS IN CONSEQUENCE OF GENETIC AND EPIGENETIC CHANGES AND/OR REDIFFERENTIATION FROM SOMATIC TUMOR CELLS TO THE STEM-LIKE CELLS REMAINS TO BE INVESTIGATED. WE PROPOSE THE IDEA OF THE RELATION BETWEEN NORMAL TISSUE STEM CELLS AND CANCER STEM CELLS AND THEIR POPULATIONS--PROGENITOR CELLS. BASED ON THIS WE HIGHLIGHT ONE OF THE MAJOR CHARACTERISTIC OF STEM CELL--PLASTICITY, WHICH IS EQUALLY IMPORTANT IN THE PHYSIOLOGICAL REGENERATION PROCESS AS WELL AS CARCINOGENESIS. FURTHERMORE, WE CONSIDER THE MICROENVIRONMENT AS A LIMITING FACTOR FOR TUMOR GENESIS IN AML, BREAST CANCER AND BRAIN TUMORS. THUS THE BIOLOGICAL PROPERTIES OF CANCER STEM CELLS ARE JUST BEGINNING TO BE REVEALED, THE CONTINUATION OF THESE STUDIES SHOULD LEAD TO THE DEVELOPMENT OF CANCER STEM CELLS TARGET THERAPIES FOR CANCER TREATMENT. 2008 8 6326 27 THE ROLE OF BCL-2 FAMILY PROTEINS IN CHRONIC LYMPHOCYTIC LEUKAEMIA. BCL-2 FAMILY PROTEINS HAVE LONG BEEN IMPLICATED IN THE PATHOLOGY OF CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL). INDEED, A NUMBER OF THESE PROTEINS HAVE BEEN SHOWN TO HAVE PROGNOSTIC IMPORTANCE IN THIS DISEASE. THE PRECISE WAYS IN WHICH THESE PROTEINS IMPACT UPON CLL AND THE WAYS IN WHICH THEY ARE REGULATED REMAIN INCOMPLETELY RESOLVED. HOWEVER, SIGNIFICANT ADVANCES HAVE BEEN RECENTLY MADE IN OUR UNDERSTANDING OF HOW THESE PROTEINS ARE CONTROLLED BY GENETIC, EPIGENETIC AND MICROENVIRONMENTAL CUES. FURTHERMORE, MAJOR PROGRESS HAS BEEN MADE IN TRYING TO TARGET THESE PROTEINS THERAPEUTICALLY. HERE WE REVIEW THE CURRENT KNOWLEDGE ABOUT THIS FAMILY OF APOPTOSIS-REGULATING PROTEINS AND HOW THEY IMPACT UPON DRUG RESISTANCE AND DISEASE PROGRESSION. WE ALSO SUMMARISE EVOLUTION IN THE DEVELOPMENT OF BCL-2 FAMILY INHIBITORS FOR THE TREATMENT OF CLL AND OTHER CANCERS. 2010 9 4693 23 NEXT GENERATION OF TARGETED MOLECULES FOR NON-HODGKIN LYMPHOMAS: SMALL-MOLECULE INHIBITORS OF INTRACELLULAR TARGETS AND SIGNALING PATHWAYS. ADVANCES IN OUR UNDERSTANDING OF THE MOLECULAR PATHOGENESIS OF B-CELL LYMPHOMA HAVE GUIDED THE DEVELOPMENT OF TARGETED THERAPIES THAT DISRUPT ABERRANT SIGNALING PATHWAYS IMPORTANT FOR COMMUNICATION WITHIN LYMPHOMA CELLS AND FOR THEIR INTERACTIONS WITH THE TUMOR MICROENVIRONMENT. THIS HAS LED TO UNPRECEDENTED THERAPEUTIC PROGRESS, WITH BIOLOGIC AGENTS THAT HAVE BEGUN TO TRANSFORM THE CARE OF PATIENTS WITH LYMPHOMA AND CHRONIC LYMPHOCYTIC LEUKEMIA. THIS REVIEW DISCUSSES THE MECHANISMS OF ACTION, CLINICAL DEVELOPMENT, AND EMERGING APPLICATIONS OF SMALL-MOLECULE INHIBITORS THAT TARGET B-CELL RECEPTOR SIGNALING PATHWAYS, B-CELL LYMPHOMA-2 INHIBITORS, SELECTIVE INHIBITORS OF NUCLEAR EXPORT, AND EPIGENETIC MODIFIERS. 2016 10 2416 28 EPIGENETIC SIGNALING OF CANCER STEM CELLS DURING INFLAMMATION. MALIGNANT TUMORS POSE A GREAT CHALLENGE TO HUMAN HEALTH, WHICH HAS LED TO MANY STUDIES INCREASINGLY ELUCIDATING THE TUMORIGENIC PROCESS. CANCER STEM CELLS (CSCS) HAVE PROFOUND IMPACTS ON TUMORIGENESIS AND DEVELOPMENT OF DRUG RESISTANCE. RECENTLY, THERE HAS BEEN INCREASED INTEREST IN THE RELATIONSHIP BETWEEN INFLAMMATION AND CSCS BUT THE MECHANISM UNDERLYING THIS RELATIONSHIP HAS NOT BEEN FULLY ELUCIDATED. INFLAMMATORY CYTOKINES PRODUCED DURING CHRONIC INFLAMMATION ACTIVATE SIGNALING PATHWAYS THAT REGULATE THE GENERATION OF CSCS THROUGH EPIGENETIC MECHANISMS. IN THIS REVIEW, WE FOCUS ON THE EFFECTS OF INFLAMMATION ON CANCER STEM CELLS, PARTICULARLY THE ROLE OF SIGNALING PATHWAYS SUCH AS NF-KAPPAB PATHWAY, STAT3 PATHWAY AND SMAD PATHWAY INVOLVED IN REGULATING EPIGENETIC CHANGES. WE HOPE TO PROVIDE A NOVEL PERSPECTIVE FOR IMPROVING STRATEGIES FOR TUMOR TREATMENT. 2021 11 2033 33 EPIGENETIC CHANGES IN SOLID AND HEMATOPOIETIC TUMORS. THERE ARE THREE CONNECTED MOLECULAR MECHANISMS OF EPIGENETIC CELLULAR MEMORY IN MAMMALIAN CELLS: DNA METHYLATION, HISTONE MODIFICATIONS, AND RNA INTERFERENCE. THE FIRST TWO HAVE NOW BEEN FIRMLY LINKED TO NEOPLASTIC TRANSFORMATION. HYPERMETHYLATION OF CPG-RICH PROMOTERS TRIGGERS LOCAL HISTONE CODE MODIFICATIONS RESULTING IN A CELLULAR CAMOUFLAGE MECHANISM THAT SEQUESTERS GENE PROMOTERS AWAY FROM TRANSCRIPTION FACTORS AND RESULTS IN STABLE SILENCING. THIS NORMALLY RESTRICTED MECHANISM IS UBIQUITOUSLY USED IN CANCER TO SILENCE HUNDREDS OF GENES, AMONG WHICH SOME CRITICALLY CONTRIBUTE TO THE NEOPLASTIC PHENOTYPE. VIRTUALLY EVERY PATHWAY IMPORTANT TO CANCER FORMATION IS AFFECTED BY THIS PROCESS. METHYLATION PROFILING OF HUMAN CANCERS REVEALS TISSUE-SPECIFIC EPIGENETIC SIGNATURES, AS WELL AS TUMOR-SPECIFIC SIGNATURES, REFLECTING IN PARTICULAR THE PRESENCE OF EPIGENETIC INSTABILITY IN A SUBSET OF CANCERS AFFECTED BY THE CPG ISLAND METHYLATOR PHENOTYPE. GENERALLY, METHYLATION PATTERNS CAN BE TRACED TO A TISSUE-SPECIFIC, PROLIFERATION-DEPENDENT ACCUMULATION OF ABERRANT PROMOTER METHYLATION IN AGING TISSUES, A PROCESS THAT CAN BE ACCELERATED BY CHRONIC INFLAMMATION AND LESS WELL-DEFINED MECHANISMS INCLUDING, POSSIBLY, DIET AND GENETIC PREDISPOSITION. THE EPIGENETIC MACHINERY CAN ALSO BE ALTERED IN CANCER BY SPECIFIC LESIONS IN EPIGENETIC EFFECTOR GENES, OR BY ABERRANT RECRUITMENT OF THESE GENES BY MUTANT TRANSCRIPTION FACTORS AND COACTIVATORS. EPIGENETIC PATTERNS ARE PROVING CLINICALLY USEFUL IN HUMAN ONCOLOGY VIA RISK ASSESSMENT, EARLY DETECTION, AND PROGNOSTIC CLASSIFICATION. PHARMACOLOGIC MANIPULATION OF THESE PATTERNS-EPIGENETIC THERAPY-IS ALSO POISED TO CHANGE THE WAY WE TREAT CANCER IN THE CLINIC. 2005 12 209 33 ACTIVATION-INDUCED CYTIDINE DEAMINASE: IN SICKNESS AND IN HEALTH. ACTIVATION INDUCED CYTIDINE DEAMINASE (AID) IS AN ESSENTIAL ENZYME OF THE ADAPTIVE IMMUNE SYSTEM. ITS CANONICAL ACTIVITY IS RESTRICTED TO B LYMPHOCYTES, PLAYING AN ESSENTIAL ROLE IN THE DIVERSIFICATION OF ANTIBODIES BY ENHANCING SPECIFICITY AND CHANGING AFFINITY. THIS IS POSSIBLE THROUGH ITS DNA DEAMINASE FUNCTION, LEADING TO MUTATIONS IN DNA. IN THE LAST DECADE, AID HAS BEEN ASSIGNED AN ADDITIONAL FUNCTION: THAT OF A POWERFUL DNA DEMETHYLATOR. ADVERSE CELLULAR CONDITIONS SUCH AS CHRONIC INFLAMMATION CAN LEAD TO ITS DEREGULATION AND OVEREXPRESSION. IT IS AN IMPORTANT DRIVER OF B-CELL LYMPHOMA DUE TO ITS NATURAL ABILITY TO MODIFY DNA THROUGH DEAMINATION, LEADING TO MUTATIONS AND EPIGENETIC CHANGES. HOWEVER, THE DEREGULATION OF AID IS NOT RESTRICTED TO LYMPHOID CELLS. RECENT FINDINGS HAVE PROVIDED NEW INSIGHTS INTO THE ROLE THAT THIS PROTEIN PLAYS IN THE DEVELOPMENT OF NON-LYMPHOID CANCERS, WITH SOME RESEARCH SHEDDING LIGHT ON NOVEL AID-DRIVEN MECHANISMS OF CELLULAR TRANSFORMATION. IN THIS REVIEW, WE PROVIDE AN UPDATED NARRATIVE OF THE NORMAL PHYSIOLOGICAL FUNCTIONS OF AID. ADDITIONALLY, WE REVIEW AND DISCUSS THE RECENT RESEARCH STUDIES THAT HAVE IMPLICATED AID IN CARCINOGENESIS IN VARYING TISSUE TYPES INCLUDING LYMPHOID AND NON-LYMPHOID CANCERS. WE REVIEW THE MECHANISMS, WHEREBY AID PROMOTES CARCINOGENESIS AND HIGHLIGHT IMPORTANT AREAS OF FUTURE RESEARCH. 2020 13 6710 34 VIRAL-INDUCED HUMAN CARCINOGENESIS: AN OXIDATIVE STRESS PERSPECTIVE. ONCOGENIC TRANSFORMATION OCCURS VIA MANY DIFFERENT MECHANISMS. ALTERATIONS IN THE EXPRESSION OF CERTAIN KEY GENES (ONCOGENES AND/OR TUMOR SUPPRESSOR GENES) CONTRIBUTE TO THE DEVELOPMENT OF THE TUMORIGENIC STATE OF UNCONTROLLED CELL PROLIFERATION. TUMOR VIRUSES' STUDIES HAVE CONTRIBUTED OVER THE LAST 2 DECADES SIGNIFICANTLY IN CANCER ETIOLOGY, FIRST BY PROVIDING VALUABLE INFORMATION ON THE MECHANISMS AND DISSECTION OF CELL SIGNALING AND GROWTH CONTROL PATHWAYS AND SECOND BY BEING CAUSATIVE AGENTS OF HUMAN NEOPLASIA. VIRUSES CONTRIBUTE TO THE DEVELOPMENT OF THE NEOPLASTIC STATE THROUGH MANY MECHANISMS: INACTIVATION OF TUMOR SUPPRESSOR GENES, HYPERSTIMULATION OF CELLULAR PROTO-ONCOGENE TRANSCRIPTION, OR BY VIRAL PROTEIN INTERFERENCE WITH THE CELLULAR TRANSCRIPTION, SIGNAL TRANSDUCTION, DNA REPAIR AND APOPTOSIS PATHWAYS AND INDUCTION OF CHRONIC OXIDATIVE STRESS. ON THE OTHER HAND, ONLY RECENTLY RESEARCH HAS PROVIDED EVIDENCE OF THE EPIGENETIC PATHWAY INVOLVEMENT AND ESPECIALLY THE DNA METHYLATION MACHINERY. TO THIS END, BOTH HYPOMETHYLATION-INDUCED ONCOGENIC ACTIVATION AND/OR HYPERMETHYLATION-INDUCED TUMOR SUPPRESSOR GENE SILENCING ARE LINKED WITH VIRAL-INDUCED CARCINOGENESIS. IN THIS REVIEW, WE DISCUSS THE CURRENT STATUS OF KNOWLEDGE ON VIRAL-ASSOCIATED CARCINOGENESIS WITH EMPHASIS ON THE MECHANISMS OF OXIDATIVE STRESS AND DNA DAMAGE INDUCTION IN HUMANS BY VIRUSES AS WELL AS IMPLICATIONS IN CANCER TREATMENT. 2010 14 2338 39 EPIGENETIC REGULATION OF INFLAMMATORY SIGNALING AND INFLAMMATION-INDUCED CANCER. EPIGENETICS COMPRISE A DIVERSE ARRAY OF REVERSIBLE AND DYNAMIC MODIFICATIONS TO THE CELL'S GENOME WITHOUT IMPLICATING ANY DNA SEQUENCE ALTERATIONS. BOTH THE EXTERNAL ENVIRONMENT SURROUNDING THE ORGANISM, AS WELL AS THE INTERNAL MICROENVIRONMENT OF CELLS AND TISSUES, CONTRIBUTE TO THESE EPIGENETIC PROCESSES THAT PLAY CRITICAL ROLES IN CELL FATE SPECIFICATION AND ORGANISMAL DEVELOPMENT. ON THE OTHER HAND, DYSREGULATION OF EPIGENETIC ACTIVITIES CAN INITIATE AND SUSTAIN CARCINOGENESIS, WHICH IS OFTEN AUGMENTED BY INFLAMMATION. CHRONIC INFLAMMATION, ONE OF THE MAJOR HALLMARKS OF CANCER, STEMS FROM PROINFLAMMATORY CYTOKINES THAT ARE SECRETED BY TUMOR AND TUMOR-ASSOCIATED CELLS IN THE TUMOR MICROENVIRONMENT. AT THE SAME TIME, INFLAMMATORY SIGNALING CAN ESTABLISH POSITIVE AND NEGATIVE FEEDBACK CIRCUITS WITH CHROMATIN TO MODULATE CHANGES IN THE GLOBAL EPIGENETIC LANDSCAPE. IN THIS REVIEW, WE PROVIDE AN IN-DEPTH DISCUSSION OF THE INTERCONNECTED CROSSTALK BETWEEN EPIGENETICS AND INFLAMMATION, SPECIFICALLY HOW EPIGENETIC MECHANISMS AT DIFFERENT HIERARCHICAL LEVELS OF THE GENOME CONTROL INFLAMMATORY GENE TRANSCRIPTION, WHICH IN TURN ENACT CHANGES WITHIN THE CELL'S EPIGENOMIC PROFILE, ESPECIALLY IN THE CONTEXT OF INFLAMMATION-INDUCED CANCER. 2022 15 2854 33 FROM HEPATITIS TO HEPATOCELLULAR CARCINOMA: A PROPOSED MODEL FOR CROSS-TALK BETWEEN INFLAMMATION AND EPIGENETIC MECHANISMS. INFLAMMATION REPRESENTS THE BODY'S NATURAL RESPONSE TO TISSUE DAMAGE; HOWEVER, CHRONIC INFLAMMATION MAY ACTIVATE CELL PROLIFERATION AND INDUCE DEREGULATION OF CELL DEATH IN AFFECTED TISSUES. CHRONIC INFLAMMATION IS AN IMPORTANT FACTOR IN THE DEVELOPMENT OF HEPATOCELLULAR CARCINOMA (HCC), ALTHOUGH THE PRECISE UNDERLYING MECHANISM REMAINS UNKNOWN. EPIGENETIC EVENTS, WHICH ARE CONSIDERED KEY MECHANISMS IN THE REGULATION OF GENE ACTIVITY STATES, ARE ALSO COMMONLY DEREGULATED IN HCC. HERE, WE REVIEW THE EVIDENCE THAT CHRONIC INFLAMMATION MIGHT DEREGULATE EPIGENETIC PROCESSES, THUS PROMOTING ONCOGENIC TRANSFORMATION, AND WE PROPOSE A WORKING HYPOTHESIS THAT EPIGENETIC DEREGULATION IS AN UNDERLYING MECHANISM BY WHICH INFLAMMATION MIGHT PROMOTE HCC DEVELOPMENT. IN THIS SCENARIO, DIFFERENT COMPONENTS OF THE INFLAMMATORY RESPONSE MIGHT DIRECTLY AND INDIRECTLY INDUCE CHANGES IN EPIGENETIC MACHINERIES ('EPIGENETIC SWITCH'), INCLUDING THOSE INVOLVED IN SETTING AND PROPAGATING NORMAL PATTERNS OF DNA METHYLATION, HISTONE MODIFICATIONS AND NON-CODING RNAS IN HEPATOCYTES. WE DISCUSS THE POSSIBILITY THAT SELF-REINFORCING CROSS-TALK BETWEEN INFLAMMATION AND EPIGENETIC MECHANISMS MIGHT AMPLIFY INFLAMMATORY SIGNALS AND MAINTAIN A CHRONIC STATE OF INFLAMMATION CULMINATING IN CANCER DEVELOPMENT. THE POTENTIAL ROLE OF INFLAMMATION-EPIGENOME INTERACTIONS IN THE EMERGENCE AND MAINTENANCE OF CANCER STEM CELLS IS ALSO DISCUSSED. 2012 16 4695 42 NF-KAPPAB ACTIVATION IN CHRONIC LYMPHOCYTIC LEUKEMIA: A POINT OF CONVERGENCE OF EXTERNAL TRIGGERS AND INTRINSIC LESIONS. THE NUCLEAR FACTOR-KAPPAB (NF-KAPPAB) PATHWAY IS CONSTITUTIVELY ACTIVATED IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) PATIENTS, AND HENCE PLAYS A MAJOR ROLE IN DISEASE DEVELOPMENT AND EVOLUTION. IN CONTRAST TO MANY OTHER MATURE B-CELL LYMPHOMAS, ONLY A FEW RECURRENTLY MUTATED GENES INVOLVED IN CANONICAL OR NON-CANONICAL NF-KAPPAB ACTIVATION HAVE BEEN IDENTIFIED IN CLL (I.E. BIRC3, MYD88 AND NFKBIE MUTATIONS) AND OFTEN AT A LOW FREQUENCY. ON THE OTHER HAND, CLL B CELLS SEEM 'ADDICTED' TO THE TUMOR MICROENVIRONMENT FOR THEIR SURVIVAL AND PROLIFERATION, WHICH IS PRIMARILY MEDIATED BY INTERACTION THROUGH A NUMBER OF CELL SURFACE RECEPTORS, E.G. THE B-CELL RECEPTOR (BCR), TOLL-LIKE RECEPTORS AND CD40, THAT IN TURN ACTIVATE DOWNSTREAM NF-KAPPAB. THE IMPORTANCE OF CELL-EXTRINSIC TRIGGERING FOR CLL PATHOPHYSIOLOGY WAS RECENTLY ALSO HIGHLIGHTED BY THE CLINICAL EFFICACY OF NOVEL DRUGS TARGETING MICROENVIRONMENTAL INTERACTIONS THROUGH THE INHIBITION OF BCR SIGNALING. IN OTHER WORDS, CLL CAN BE CONSIDERED A PROTOTYPE DISEASE FOR STUDYING THE INTRICATE INTERPLAY BETWEEN EXTERNAL TRIGGERS AND INTRINSIC ABERRATIONS AND THEIR COMBINED IMPACT ON DISEASE EVOLUTION. IN THIS REVIEW, WE WILL DISCUSS THE CURRENT UNDERSTANDING OF MECHANISMS UNDERLYING NF-KAPPAB DEREGULATION IN CLL, INCLUDING MICRO-ENVIRONMENTAL, GENETIC AND EPIGENETIC EVENTS, AND SUMMARIZE DATA GENERATED IN MURINE MODELS RESEMBLING HUMAN CLL. FINALLY, WE WILL ALSO DISCUSS DIFFERENT STRATEGIES UNDERTAKEN TO INTERVENE WITH THE NF-KAPPAB PATHWAY AND ITS UPSTREAM MEDIATORS. 2016 17 3799 28 INTERPLAY BETWEEN INFLAMMATION AND EPIGENETIC CHANGES IN CANCER. IMMUNE RESPONSES CAN SUPPRESS TUMORIGENESIS, BUT ALSO CONTRIBUTE TO CANCER INITIATION AND PROGRESSION SUGGESTING A COMPLEX INTERACTION BETWEEN THE IMMUNE SYSTEM AND CANCER. EPIGENETIC ALTERATIONS, WHICH ARE HERITABLE CHANGES IN GENE EXPRESSION WITHOUT CHANGES TO THE DNA SEQUENCE, ALSO PLAY A ROLE IN CARCINOGENESIS THROUGH SILENCING EXPRESSION OF TUMOR SUPPRESSOR GENES AND ACTIVATING ONCOGENIC SIGNALING. INTERESTINGLY, EPITHELIAL CELLS AT SITES OF CHRONIC INFLAMMATION UNDERGO DNA METHYLATION ALTERATIONS THAT ARE SIMILAR TO THOSE PRESENT IN CANCER CELLS, SUGGESTING THAT INFLAMMATION MAY INITIATE CANCER-SPECIFIC EPIGENETIC CHANGES IN EPITHELIAL CELLS. FURTHERMORE, EPIGENETIC CHANGES OCCUR DURING IMMUNE CELL DIFFERENTIATION AND PARTICIPATE IN REGULATING THE IMMUNE RESPONSE, INCLUDING THE REGULATION OF INFLAMMATORY CYTOKINES. CANCER CELLS UTILIZE EPIGENETIC SILENCING OF IMMUNE-RELATED GENES TO EVADE THE IMMUNE RESPONSE. THIS CHAPTER WILL DETAIL THE INTERACTIONS BETWEEN INFLAMMATION AND EPIGENETICS IN TUMOR INITIATION, PROMOTION, AND IMMUNE EVASION AND HOW THESE CONNECTIONS ARE BEING LEVERAGED IN CANCER PREVENTION AND TREATMENT. 2016 18 2380 33 EPIGENETIC REGULATION OF WNT SIGNALING IN CHRONIC LYMPHOCYTIC LEUKEMIA. CERTAIN WNT AND WNT NETWORK TARGET GENES ARE EXPRESSED AT HIGHER OR LOWER LEVELS IN CHRONIC LYMPHOCYTIC LEUKEMIA COMPARED WITH NORMAL B-CELLS. THIS INCLUDES UPREGULATION OF NUCLEAR COMPLEX GENES, AS WELL AS GENES FOR CYTOPLASMIC PROTEINS AND WNT LIGANDS AND THEIR COGNATE RECEPTORS. IN ADDITION, EPIGENETIC SILENCING OF SEVERAL NEGATIVE REGULATORS OF THE WNT PATHWAY HAVE BEEN IDENTIFIED. THE BALANCE BETWEEN EPIGENETIC DOWNREGULATION OF NEGATIVE EFFECTOR GENES AND INCREASED EXPRESSION OF POSITIVE EFFECTOR GENES DEMONSTRATE THAT THE EPIGENETIC DOWNREGULATION OF WNT ANTAGONISTS IS ONE MECHANISM, PERHAPS THE MAIN MECHANISM, THAT IS PERMISSIVE TO ACTIVE WNT SIGNALING IN CHRONIC LYMPHOCYTIC LEUKEMIA. MOREOVER, CONSTITUTIVE ACTIVATION OF THE WNT NETWORK AND TARGET GENES IS LIKELY TO IMPACT ON ADDITIONAL INTERACTING SIGNALING PATHWAYS. BASED ON PUBLISHED STUDIES, WE PROPOSE A MODEL OF WNT SIGNALING THAT INVOLVES MAINLY PERMISSIVE EXPRESSION, AND SOMETIMES OVEREXPRESSION, OF POSITIVE EFFECTORS AND DOWNREGULATION OF NEGATIVE REGULATORS IN THE NETWORK. IN THIS MODEL, DNA METHYLATION, HISTONE MODIFICATIONS AND ALTERED EXPRESSION OF MICRORNA MOLECULES INTERACT TO ALLOW CONTINUOUS WNT SIGNALING. 2010 19 4539 31 MULTISTAGE CARCINOGENESIS IN MOUSE SKIN. THE MOUSE SKIN MODEL OF MULTISTAGE CARCINOGENESIS HAS FOR MANY YEARS PROVIDED A CONCEPTUAL FRAMEWORK FOR STUDYING CARCINOGENESIS MECHANISMS AND POTENTIAL MEANS FOR INHIBITING SPECIFIC STAGES OF CARCINOGENESIS. THE PROCESS OF SKIN CARCINOGENESIS INVOLVES THE STEPWISE ACCUMULATION OF GENETIC CHANGE ULTIMATELY LEADING TO MALIGNANCY. INITIATION, THE FIRST STEP IN MULTISTAGE SKIN CARCINOGENESIS INVOLVES CARCINOGEN-INDUCED GENETIC CHANGES. A TARGET GENE IDENTIFIED FOR SOME SKIN TUMOR INITIATORS IS C-HA-RAS. THE SECOND STEP, THE PROMOTION STAGE, INVOLVES PROCESSES WHEREBY INITIATED CELLS UNDERGO SELECTIVE CLONAL EXPANSION TO FORM VISIBLE PREMALIGNANT LESIONS TERMED PAPILLOMAS. THE PROCESS OF TUMOR PROMOTION INVOLVES THE PRODUCTION AND MAINTENANCE OF A SPECIFIC AND CHRONIC HYPERPLASIA CHARACTERIZED BY A SUSTAINED CELLULAR PROLIFERATION OF EPIDERMAL CELLS. THESE CHANGES ARE BELIEVED TO RESULT FROM EPIGENETIC MECHANISMS SUCH AS ACTIVATION OF THE CELLULAR RECEPTOR, PROTEIN KINASE C, BY SOME CLASSES OF TUMOR PROMOTERS. THE PROGRESSION STAGE INVOLVES THE CONVERSION OF PAPILLOMAS TO MALIGNANT TUMORS, SQUAMOUS CELL CARCINOMAS. THE ACCUMULATION OF ADDITIONAL GENETIC CHANGES IN CELLS COMPRISING PAPILLOMAS HAS BEEN CORRELATED WITH TUMOR PROGRESSION, INCLUDING TRISOMIES OF CHROMOSOMES 6 AND 7 AND LOSS OF HETEROZYGOSITY. THE CURRENT REVIEW FOCUSES ON THE MECHANISMS INVOLVED IN MULTISTAGE SKIN CARCINOGENESIS, A SUMMARY OF KNOWN INHIBITORS OF SPECIFIC STAGES AND THEIR PROPOSED MECHANISMS OF ACTION, AND THE RELEVANCE OF THIS MODEL SYSTEM TO HUMAN CANCER. 1992 20 6906 29 [THE ROLE OF GLYCANS IN CANCER DEVELOPMENT AND PROGRESSION. CLINICAL APPLICATIONS]. CHANGES IN GLYCOSYLATION PATTERN OF CELL SURFACE, BODY FLUIDS AND EXTRACELLULAR MATRIX GLYCOCONJUGATES IS A CHARACTERISTIC FEATURE OF TUMOR CELL MALIGNANCY. THESE CHANGES ARE THE RESULT OF MUTATIONS OF TUMOR-ASSOCIATED GENES AS WELL AS EPIGENETIC CHANGES IN THE TUMOR ENVIRONMENT, INCLUDING NUTRIENT INFLUX, HYPOXIA, CYTOKINE EXPRESSION AND STIMULATION OF CHRONIC INFLAMMATION. THE UNIQUE SET OF CELL SURFACE GLYCOANTIGENS ON NEOPLASTIC CELLS IS RECOGNIZED BY ENDOGENOUS LECTINS LOCATED IN THE EXTRACELLULAR MATRIX, VASCULAR ENDOTHELIUM, ON LEUKOCYTES OR PLATELETS, AND HAS AN IMPACT ON DISRUPTING BASIC CELLULAR PROCESSES, SUCH AS INTERCELLULAR RECOGNITION, CELL-CELL ADHESION OR CELL-ECM INTERACTION. THESE CHANGES HAVE A CRITICAL IMPACT ON THE MIGRATION, INVASIVE AND METASTATIC POTENTIAL OF NEOPLASTIC CELLS AND MODULATE THE IMMUNE RESPONSE. THIS UNIQUE PATTERN OF SUGAR ANTIGENS ON THE CANCER CELLS CAN BE A VAULABLE MARKER TO IDENTIFY THEM, DETERMINE THE STAGE OF THE DISEASE AS WELL AS BE A TARGET OF ANTI-CANCER THERAPY. 2021