1 1378 114 DEVELOPMENTAL PROGRAMS ARE KEPT ALIVE DURING ADULTHOOD BY STEM CELLS: THE AGING ASPECT. STEM CELLS ARE FUNDAMENTAL FOR LIFE-LONG PRESERVATION OF CELLULAR SOMATIC MAINTENANCE. TISSUE-BORNE STEM CELLS REPLENISH WORN-OUT CRITICAL ELEMENTS. PROVIDED THEY REMAIN FIT OVER LIFETIME, ENDURING STEM CELL ACTIVITIES AVERT THE EMERGENCE OF AGE-ASSOCIATED CHRONIC DEGENERATIVE DISEASES AND PATHOLOGIES. ALTHOUGH EXPERIMENTALLY STILL UNCLEAR, IT IS ASSUMED THAT STEM CELLS RESIDE IN PROTECTED NICHES. FRESHLY ISOLATED MESENCHYMAL STEM CELLS EXHIBIT DONOR-SPECIFIC ABERRATIONS, WHICH CANNOT SOLELY BE ASCRIBED TO DIFFERENCES IN GENETIC BACKGROUND. BESIDES INEVITABLY ACCUMULATING INTRINSIC MODIFICATIONS, THE SYSTEMIC ENVIRONMENT ALSO IMPACTS ON BASIC PROPERTIES OF MESENCHYMAL STEM CELLS SUCH AS THEIR INHERENT MULTI-LINEAGE DIFFERENTIATION POTENTIAL. CHRONIC SYSTEMIC ABERRATIONS OVER TIME COMPRISE UNWHOLESOME INFLUENCES, IN PARTICULAR IN TERMS OF REGENERATION AND REPAIR WHEN STEM CELLS RECAPITULATE DISTINCT DEVELOPMENTAL PROGRAMS. DURING OR THEREAFTER, STEM CELLS CAN DIVERSIFY EITHER BECAUSE OF INSUFFICIENTLY SILENCING ACTIVATED BUILDING CYCLES, OR BY ACQUIRING EPIGENETIC DEVIATIONS. 2013 2 4 32 "MIX OF MICS"- PHENOTYPIC AND BIOLOGICAL HETEROGENEITY OF "MULTIPOTENT" MUSCLE INTERSTITIAL CELLS (MICS). THE CAPACITY OF ADULT SKELETAL MUSCLE FOR REGENERATION APPEARS TO BE LIMITED, WITH PROGRESSIVE IMPAIRMENT IN REPAIR EFFICIENCY OF INJURED MUSCLES OBSERVED IN CHRONIC MUSCULAR DISORDERS AND DURING AGING. WHILE SATELLITE CELLS, THE COMMITTED ADULT MUSCLE STEM CELLS, ARE THE MAIN DIRECT CELL SOURCE SUPPORTING THE REGENERATIVE POTENTIAL OF ADULT SKELETAL MUSCLES, THE CHARACTERIZATION OF THE CELL TYPES AND SIGNALS THAT CONSTITUTE THE FUNCTIONAL "NICHE" OF SATELLITE CELLS IS CURRENTLY THE OBJECT OF INTENSE INVESTIGATION. RECENT STUDIES HAVE IDENTIFIED A FUNCTIONAL RELATIONSHIP BETWEEN SATELLITE CELLS AND VARIOUS CELL TYPES LOCATED IN KEY ANATOMICAL POSITION, SUCH AS THE INTERSTITIUM OF SKELETAL MUSCLES. THIS HETEROGENEOUS POPULATION OF MUSCLE INTERSTITIAL CELLS (MICS) APPEARS TO RETAIN AN INTRINSIC MULTIPOTENCY WITHIN THE MESODERMAL LINEAGE, AND THEIR DIRECT OR INDIRECT CONTRIBUTION TO MYOFIBER TURNOVER, REPAIR AND DEGENERATION HAS BEEN SUGGESTED BY MANY STUDIES THAT WILL BE REVIEWED HERE. GIVEN THE EXISTING GAP OF KNOWLEDGE ON LINEAGE IDENTITY AND FUNCTIONAL PROPERTIES OF MICS, THEIR DETAILED CHARACTERIZATION AT THE SINGLE CELL LEVEL HOLDS THE PROMISE TO PROVIDE KEY INSIGHT INTO THE COMPOSITION OF THIS HETEROGENEOUS POPULATION AND THE DYNAMIC TRANSITION THROUGH DISTINCT SUB-POPULATIONS IN HEALTHY, DISEASED AND AGING MUSCLES. THIS REVIEW PROVIDES AN OVERVIEW OF THE RESULTS OF VARIOUS STUDIES DESCRIBING THE PHENOTYPE AND THE FUNCTION OF CELLS ISOLATED FROM SKELETAL MUSCLE INTERSTITIUM, AND DISCUSSES THE IMPORTANCE OF SINGLE CELL TRANSCRIPTION PROFILING IN ORDER TO DECIPHER THE FUNCTIONAL AND PHENOTYPICAL HETEROGENEITY OF MUSCLE INTERSTITIAL CELLS (MICS). 2012 3 389 23 AN INTEGRATIVE HYPOTHESIS LINKING CANCER, DIABETES AND ATHEROSCLEROSIS: THE ROLE OF MUTATIONS AND EPIGENETIC CHANGES. IT APPEARS THAT THE DISEASE STATES OF CANCER, ALTHEROSCLEROSIS AND DIABETES MIGHT SHARE A COMMON ETIOLOGY. THESE CHRONIC DISEASES APPEAR TO BE MULTI-STAGED IN THEIR PROGRESSION, WITH GENETIC, NUTRITIONAL, PSYCHO-SOCIAL, ENVIRONMENTAL AND VIRAL FACTORS INFLUENCING THEIR APPEARANCE. WE OFFERED A HYPOTHESIS (A "MUTATION THEORY OF DISEASE"), STATING THAT THESE DISEASES CAN BE DESCRIBED BY INITIATION AND PROMOTION PHASES; INITIATION BEING THE RESULT OF THE PRODUCTION OF MUTATED CELLS AFTER UNREPAIRED DAMAGED DNA IS REPLICATED; PROMOTION BEING THE SELECTIVE PROLIFERATION OF THE INITIATED CELLS TO FORM CLONES OF MUTATED CELLS. IT WAS FURTHER POSTULATED THAT PROMOTION AFFECTS CELL PROLIFERATION BY ALTERING A MEMBRANE-CA++ REGULATORY SYSTEM. DEPENDING ON THE NATURE OF THE MUTATION IN THE CLONE OF CELLS, SPECIFIC DISEASE STATES WOULD RESULT. THE ROLES OF RADIATIONS, CHEMICALS, VIRUSES, GENES, NUTRITION AND PSYCHO-SOCIAL STRESS WERE RELATED TO EITHER THE INITIATION (MUTATION PRODUCTION) OR THE PROMOTION (CELL PROLIFERATION) PHASE OF THESE DISEASES. 1980 4 1923 23 ENVIRONMENTAL EPIGENETIC MODIFICATIONS AND REPROGRAMMING-RECALCITRANT GENES. THE TERM "ENVIRONMENTAL EPIGENETIC MODIFICATIONS" REFERS TO ALTERATIONS IN PHENOTYPE TRIGGERED BY ENVIRONMENTAL STIMULI VIA EPIGENETIC MECHANISMS. EPIDEMIOLOGIC AND ANIMAL MODEL STUDIES SHOW THAT A SUBSET OF SUCH ENVIRONMENTAL EPIGENETIC MARKS MAY AFFECT SUSCEPTIBILITY TO CHRONIC DISEASES. A GROWING BODY OF EVIDENCE REGARDING INCOMPLETENESS OF REPROGRAMMING INDICATES THAT THE POTENTIAL RETENTION OF PATHOGENIC ENVIRONMENTAL EPIGENETICS IN HUMAN INDUCED PLURIPOTENT STEM CELLS (IPSCS) SHOULD BE SERIOUSLY CONSIDERED. GIVEN THIS POSSIBILITY, THE OPTIMIZATION OF METHODS FOR THE GENERATION OF HUMAN INDUC PLURIPOTENT STEM CELLS MAY REQUIRE THE IDENTIFICATION OF EPIGENETICALLY APPROPRIATE SOMATIC CELL SOURCES. SIMILARLY, TECHNIQUES FOR CONTROLLING EPIGENETIC MODIFICATION BY ENVIRONMENTAL FACTORS MAY ALSO PLAY A CRITICAL ROLE IN THE DEVELOPMENT OF EPIGENETICALLY STABLE SOURCES OF PLURIPOTENT STEM CELLS. 2010 5 3651 20 INCREASING COMPLEXITY OF MOLECULAR LANDSCAPES IN HUMAN HEMATOPOIETIC STEM AND PROGENITOR CELLS DURING DEVELOPMENT AND AGING. THE PAST FIVE DECADES HAVE SEEN SIGNIFICANT PROGRESS IN OUR UNDERSTANDING OF HUMAN HEMATOPOIESIS. THIS HAS IN PART BEEN DUE TO THE UNPRECEDENTED DEVELOPMENT OF ADVANCED TECHNOLOGIES, WHICH HAVE ALLOWED THE IDENTIFICATION AND CHARACTERIZATION OF RARE SUBSETS OF HUMAN HEMATOPOIETIC STEM AND PROGENITOR CELLS AND THEIR LINEAGE TRAJECTORIES FROM EMBRYONIC THROUGH TO ADULT LIFE. ADDITIONALLY, SURROGATE IN VITRO AND IN VIVO MODELS, ALTHOUGH NOT FULLY RECAPITULATING HUMAN HEMATOPOIESIS, HAVE SPURRED ON THESE SCIENTIFIC ADVANCES. THESE APPROACHES HAVE HEIGHTENED OUR KNOWLEDGE OF HEMATOLOGICAL DISORDERS AND DISEASES AND HAVE LED TO THEIR IMPROVED DIAGNOSIS AND THERAPIES. HERE, WE REVIEW HUMAN HEMATOPOIESIS AT EACH END OF THE AGE SPECTRUM, DURING EMBRYONIC AND FETAL DEVELOPMENT AND ON AGING, PROVIDING EXEMPLARS OF RECENT PROGRESS IN DECIPHERING THE INCREASINGLY COMPLEX CELLULAR AND MOLECULAR HEMATOPOIETIC LANDSCAPES IN HEALTH AND DISEASE. THIS REVIEW CONCLUDES BY HIGHLIGHTING LINKS BETWEEN CHRONIC INFLAMMATION AND METABOLIC AND EPIGENETIC CHANGES ASSOCIATED WITH AGING AND IN THE DEVELOPMENT OF CLONAL HEMATOPOIESIS. 2022 6 3418 25 HUMAN HEALTH CONSEQUENCES OF ENVIRONMENTALLY-MODULATED GENE EXPRESSION: POTENTIAL ROLES OF ELF-EMF INDUCED EPIGENETIC VERSUS MUTAGENIC MECHANISMS OF DISEASE. IN ORDER TO DETERMINE IF THERE MIGHT BE BIOLOGICAL AND HEALTH CONSEQUENCES AFTER EXPOSURES TO EXTREMELY-LOW FREQUENCY ELECTROMAGNETIC FIELDS (ELF-EMF), EITHER EXPERIMENTALLY OR EPIDEMIOLOGICALLY, MECHANISTIC UNDERSTANDING OF THE POTENTIAL MEANS BY WHICH ANY ENVIRONMENTAL AGENT CAN AFFECT CELLS IN A MULTICELLULAR ORGANISM HAS TO BE REVIEWED. THE GOAL OF THIS LIMITED REVIEW IS TO DEMONSTRATE THAT, WHILE THE PREVAILING PARADIGM OF THE ENVIRONMENTALLY-INDUCED ACUTE AND CHRONIC DISEASES INVOLVES EITHER CELL KILLING (CYTOTOXICITY) OR GENE/CHROMOSOME MUTATIONS (GENOTOXICITY), ALTERATION OF THE EXPRESSION OF GENETIC INFORMATION AT THE TRANSCRIPTIONAL (TURNING GENES "ON" OR "OFF"), TRANSLATIONAL (STABILIZING OR DE-STABILIZING THE GENETIC MESSAGE), OR POSTTRANSLATIONAL (ALTERING THE GENE PRODUCT OR PROTEIN) LEVELS HAS THE POTENTIAL TO CONTRIBUTE TO VARIOUS DISEASES. THIS LATTER MECHANISM, "EPIGENETIC" TOXICITY, UNLIKE THE FORMER TWO WHICH ARE IRREVERSIBLE, IS CHARACTERIZED BY THRESHOLD-LIKE ACTION, MULTIPLE BIOCHEMICAL PATHWAYS AND CHRONIC, REGULAR EXPOSURES TO BE EFFECTIVE. ULTIMATELY, EPIGENETIC TOXICANTS AFFECT ONE OF FOUR POTENTIAL CELL STATES, NAMELY ALTERATION OF CELL PROLIFERATION, CELL DIFFERENTIATION, PROGRAMMED CELL DEATH (APOPTOSIS) OR ADAPTIVE RESPONSES OF DIFFERENTIATED CELLS. 2000 7 49 26 A CURRENT GENETIC AND EPIGENETIC VIEW ON HUMAN AGING MECHANISMS. THE PROCESS OF AGING IS ONE OF THE MOST COMPLEX AND INTRIGUING BIOLOGICAL PHENOMENONS. AGING IS A GENETICALLY REGULATED PROCESS IN WHICH THE ORGANISM'S MAXIMUM LIFESPAN POTENTIAL IS PRE-DETERMINED, WHILE THE RATE OF AGING IS INFLUENCED BY ENVIRONMENTAL FACTORS AND LIFESTYLE. CONSIDERING THE COMPLEXITY OF MECHANISMS INVOLVED IN THE REGULATION OF AGING PROCESS, UP TO THIS DATE THERE ISN'T A MAJOR, UNIFYING THEORY WHICH COULD EXPLAIN THEM. AS GENETIC/EPIGENETIC AND ENVIRONMENTAL FACTORS BOTH INEVITABLY INFLUENCE THE AGING PROCESS, HERE WE PRESENT A REVIEW ON THE GENETIC AND EPIGENETIC REGULATION OF THE MOST IMPORTANT MOLECULAR AND CELLULAR MECHANISMS INVOLVED IN THE PROCESS OF AGING. BASED ON THE STUDIES ON OXIDATIVE STRESS, METABOLISM, GENOME STABILITY, EPIGENETIC MODIFICATIONS AND CELLULAR SENESCENCE IN ANIMAL MODELS AND HUMANS, WE GIVE AN OVERVIEW OF KEY GENETIC AND MOLECULAR PATHWAYS RELATED TO AGING. AS MOST OF GENETIC MANIPULATIONS WHICH INFLUENCE THE AGING PROCESS ALSO AFFECT REPRODUCTION, WE DISCUSS AGING IN HUMANS AS A POST-REPRODUCTIVE GENETICALLY DETERMINED PROCESS. AFTER THE AGE OF REPRODUCTIVE SUCCESS, AGING CONTINOUSLY PROGRESSES WHICH CLINICALLY COINCIDES WITH THE ONSET OF MOST CHRONIC DISEASES, CANCERS AND DEMENTIONS. AS EVOLUTION SHAPES THE GENOMES FOR REPRODUCTIVE SUCCESS AND NOT FOR POST-REPRODUCTIVE SURVIVAL, AGING COULD BE DEFINED AS A PROTECTIVE MECHANISM WHICH ENSURES THE PRESERVATION AND PROGRESS OF SPECIES THROUGH THE MODIFICATION, TRASMISSION AND IMPROVEMENT OF GENETIC MATERIAL. 2009 8 705 21 BUILDING RISK-ON-A-CHIP MODELS TO IMPROVE BREAST CANCER RISK ASSESSMENT AND PREVENTION. PREVENTIVE ACTIONS FOR CHRONIC DISEASES HOLD THE PROMISE OF IMPROVING LIVES AND REDUCING HEALTHCARE COSTS. FOR SEVERAL DISEASES, INCLUDING BREAST CANCER, MULTIPLE RISK AND PROTECTIVE FACTORS HAVE BEEN IDENTIFIED BY EPIDEMIOLOGISTS. THE IMPACT OF MOST OF THESE FACTORS HAS YET TO BE FULLY UNDERSTOOD AT THE ORGANISM, TISSUE, CELLULAR AND MOLECULAR LEVELS. IMPORTANTLY, COMBINATIONS OF EXTERNAL AND INTERNAL RISK AND PROTECTIVE FACTORS INVOLVE COOPERATIVITY THUS, SYNERGIZING OR ANTAGONIZING DISEASE ONSET. MODELS ARE NEEDED TO MECHANISTICALLY DECIPHER CANCER RISKS UNDER DEFINED CELLULAR AND MICROENVIRONMENTAL CONDITIONS. HERE, WE BRIEFLY REVIEW BREAST CANCER RISK MODELS BASED ON 3D CELL CULTURE AND PROPOSE TO IMPROVE RISK MODELING WITH LAB-ON-A-CHIP APPROACHES. WE SUGGEST EPITHELIAL TISSUE POLARITY, DNA REPAIR AND EPIGENETIC PROFILES AS ENDPOINTS IN RISK ASSESSMENT MODELS AND DISCUSS THE DEVELOPMENT OF 'RISKS-ON-CHIPS' INTEGRATING BIOSENSORS OF THESE ENDPOINTS AND OF GENERAL TISSUE HOMEOSTASIS. RISKS-ON-CHIPS WILL HELP IDENTIFY BIOMARKERS OF RISK, SERVE AS SCREENING PLATFORMS FOR CANCER PREVENTIVE AGENTS, AND PROVIDE A BETTER UNDERSTANDING OF RISK MECHANISMS, HENCE RESULTING IN NOVEL DEVELOPMENTS IN DISEASE PREVENTION. 2013 9 2592 21 EPIGENETICS OF RENAL DEVELOPMENT AND DISEASE. AN UNDERSTANDING OF EPIGENETICS IS INDISPENSABLE TO OUR UNDERSTANDING OF GENE REGULATION UNDER NORMAL AND PATHOLOGICAL STATES. THIS KNOWLEDGE WILL HELP WITH DESIGNING BETTER THERAPEUTIC APPROACHES IN REGENERATIVE TISSUE MEDICINE. EPIGENETICS ALLOWS US TO PARSE OUT THE MECHANISMS BY WHICH TRANSCRIPTIONAL REGULATORS GAIN ACCESS TO SPECIFIC GENE LOCI THEREBY IMPRINTING EPIGENETIC INFORMATION AFFECTING CHROMATIN FUNCTION. THIS EPIGENETIC MEMORY FORMS THE BASIS OF CELL LINEAGE SPECIFICATION IN MULTICELLULAR ORGANISMS. POST-TRANSLATIONAL MODIFICATIONS TO DNA AND HISTONES IN THE NUCLEOSOME CORE FORM CHARACTERISTIC EPIGENETIC CODES WHICH ARE DISTINCT FOR SELF-RENEWING AND PRIMED PROGENITOR CELL POPULATIONS. STUDIES OF CHROMATIN MODIFIERS AND MODIFICATIONS IN RENAL DEVELOPMENT AND DISEASE HAVE BEEN GAINING MOMENTUM. BOTH CONGENITAL AND ADULT RENAL DISEASES HAVE A GENE-ENVIRONMENT COMPONENT, WHICH INVOLVES ALTERATIONS TO THE EPIGENETIC INFORMATION IMPRINTED DURING DEVELOPMENT. THIS EPIGENETIC MEMORY MUST BE CHARACTERIZED TO ESTABLISH OPTIMAL TREATMENT OF BOTH ACUTE AND CHRONIC RENAL DISEASES. 2016 10 1027 23 CIRCULATING MIRNAS IN SUCCESSFUL AND UNSUCCESSFUL AGING. A MINI-REVIEW. AGING IS A MULTIFACTORIAL PROCESS THAT AFFECTS THE ORGANISMS AT GENETIC, MOLECULAR AND CELLULAR LEVELS. THIS PROCESS MODIFIES SEVERAL TISSUES WITH A NEGATIVE IMPACT ON CELLS PHYSIOLOGY, TISSUES AND ORGANS FUNCTIONALITY, ALTERING THEIR REGENERATION CAPACITY. THE CHRONIC LOW-GRADE INFLAMMATION TYPICAL OF AGING, DEFINED AS INFLAMMAGING, IS A COMMON BIOLOGICAL FACTOR RESPONSIBLE FOR THE DECLINE AND BEGINNING OF THE DISEASE IN AGE. A MURINE PARABIOSIS MODEL THAT COMBINES THE VASCULAR SYSTEM OF OLD AND YOUNG ANIMALS, SUGGESTS THAT SOLUBLE FACTORS RELEASED BY YOUNG INDIVIDUALS MAY IMPROVE THE REGENERATIVE POTENTIAL OF OLD TISSUE. THEREFORE, CIRCULATING FACTORS HAVE A KEY ROLE IN THE INDUCTION OF AGING PHENOTYPE. MOREOVER, LIFESTYLE CAN INFLUENCE THE PHYSIOLOGICAL STATUS OF MULTIPLE ORGANS, VIA EPIGENETIC MECHANISMS. RECENTLY, MICRORNAS ARE CONSIDERED POTENTIAL SENSORS OF AGING. 2019 11 6466 27 TISSUE STEM CELLS AND CANCER STEM CELLS: POTENTIAL IMPLICATIONS FOR GASTRIC CANCER. GASTRIC CANCER REMAINS THE SECOND LEADING CAUSE OF DEATH IN THE WORLD TODAY, MAKING THE SEARCH FOR ITS MOLECULAR AND CELLULAR BASIS AN IMPORTANT PRIORITY. THOUGH RECOGNITION OF THE TIGHT LINK BETWEEN INFLAMMATION AND TUMORIGENESIS IS CENTURIES OLD, ONLY RECENTLY ARE THE PIECES OF THE ETIOLOGICAL PUZZLE BEGINNING TO FALL TOGETHER. RECENT ADVANCES IN GASTRIC STEM CELL BIOLOGY APPEAR TO BE CENTRAL TO THIS SLOWLY RESOLVING PUZZLE. AT LEAST TWO TYPES OF STEM CELLS MAY BE IMPORTANT. RESIDENT ADULT OR TISSUE STEM CELLS MAY, IN A CHRONICALLY INFLAMED ENVIRONMENT, SLOWLY ACQUIRE A SERIES OF GENETIC AND EPIGENETIC CHANGES THAT LEAD TO THEIR EMERGENCE AS ''CANCER STEM CELLS''. THIS SCENARIO HAS NOT YET BEEN PROVEN EXPERIMENTALLY, ALTHOUGH THE FIRST STEP, PROSPECTIVE RECOGNITION OF A GASTRIC STEM CELL HAS RECENTLY BEEN CONQUERED. ALTERNATIVELY, THE SETTING OF CHRONIC INFLAMMATORY STRESS AND INJURY MAY LEAD TO LOSS OF THE INDIGENOUS GASTRIC STEM CELLS FROM THEIR NICHES; BONE MARROW DERIVED STEM CELLS MAY THEN BE RECRUITED TO AND ENGRAFT INTO THE GASTRIC EPITHELIUM. SUCH RECRUITED CELLS HAVE THE POTENTIAL TO CONTRIBUTE TO THE TUMOR MASS. INDEED, EVIDENCE SUPPORTING THIS SCENARIO HAS BEEN PUBLISHED. HERE, WE REVIEW THESE RECENT FINDINGS AND DISCUSS IMPLICATIONS FOR THE FUTURE. 2008 12 736 26 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 13 761 27 CATEGORIZING THE CHARACTERISTICS OF HUMAN CARCINOGENS: A NEED FOR SPECIFICITY. THE INTERNATIONAL AGENCY FOR RESEARCH ON CANCER (IARC) HAS RECENTLY PROPOSED EMPLOYING "TEN KEY CHARACTERISTICS OF HUMAN CARCINOGENS" (TKCS) TO DETERMINE THE POTENTIAL OF AGENTS FOR HARMFUL EFFECTS. THE TKCS SEEM LIKELY TO CONFUSE THE UNSATISFACTORY CORRELATION FROM TESTING REGIMES THAT HAVE IGNORED THE DIFFERENCES EVIDENT WHEN CELLULAR CHANGES ARE COMPARED IN SHORT AND LONG-LIVED SPECIES, WITH THEIR VERY DIFFERENT STEM CELL AND SOMATIC CELL PHYLOGENIES. THE PROPOSED CHARACTERISTICS ARE SO BROAD THAT THEIR USE WILL LEAD TO AN INCREASE IN THE CURRENT UNACCEPTABLY HIGH RATE OF FALSE POSITIVES. IT COULD BE AN INFORMATIVE EXPERIMENT TO TAKE WELL-ESTABLISHED APPROVED THERAPEUTICS WITH WELL-KNOWN HUMAN SAFETY PROFILES AND TEST THEM AGAINST THIS NEW TKC PARADIGM. CANCERS ARE INITIATED AND DRIVEN BY HERITABLE AND TRANSIENT CHANGES IN GENE EXPRESSION, EXPAND CLONALLY, AND PROGRESS VIA ADDITIONAL ASSOCIATED ACQUIRED MUTATIONS AND EPIGENETIC ALTERATIONS THAT PROVIDE CELLS WITH AN EVOLUTIONARY ADVANTAGE. THE GENOTOXICITY TESTING PROTOCOLS CURRENTLY EMPLOYED AND REQUIRED BY REGULATION, EMPHASIZE TESTING FOR THE MUTATIONAL POTENTIAL OF THE TEST AGENT. TWO-YEAR, CHRONIC RODENT CANCER BIOASSAYS ARE INTENDED TO TEST FOR THE ENTIRE SPECTRUM OF CARCINOGENIC TRANSFORMATION. THE USE OF CYTOTOXIC DOSES CAUSING INCREASED, SUSTAINED CELL PROLIFERATION THAT FACILITATES ACCUMULATED GENETIC DAMAGE LEADS TO A HIGH FALSE-POSITIVE RATE OF TUMOR INDUCTION. CURRENT CANCER HAZARD ASSESSMENT PROTOCOLS AND WEIGHT-OF-THE-EVIDENCE ANALYSIS OF AGENT-SPECIFIC CANCER RISK ALIGN POORLY WITH THE PATHOGENESIS OF HUMAN CARCINOMA AND SO NEED MODERNIZATION AND IMPROVEMENT IN WAYS SUGGESTED HERE. 2021 14 2566 28 EPIGENETICS MECHANISMS IN RENAL DEVELOPMENT. APPRECIATION FOR THE ROLE OF EPIGENETIC MODIFICATIONS IN THE DIAGNOSIS AND TREATMENT OF DISEASES IS FAST GAINING ATTENTION. TREATMENT OF CHRONIC KIDNEY DISEASE STEMMING FROM DIABETES OR HYPERTENSION AS WELL AS WILMS TUMOR WILL ALL PROFIT FROM KNOWLEDGE OF THE CHANGES IN THE EPIGENOMIC LANDSCAPES. TO DO SO, IT IS ESSENTIAL TO CHARACTERIZE THE EPIGENOMIC MODIFIERS AND THEIR MODIFICATIONS UNDER NORMAL PHYSIOLOGICAL CONDITIONS. THE TRANSCRIPTION FACTOR PAX2 WAS IDENTIFIED AS A MAJOR EPIGENETIC PLAYER IN THE EARLY SPECIFICATION OF THE KIDNEY. NOTABLY, THE PROGENITORS OF ALL NEPHRONS THAT RESIDE IN THE CAP MESENCHYME DISPLAY A UNIQUE BIVALENT HISTONE SIGNATURE (EXPRESSING REPRESSIVE EPIGENETIC MARKS ALONGSIDE ACTIVATION MARKS) ON LINEAGE-SPECIFIC GENES. THESE CELLS ARE DEEMED POISED FOR DIFFERENTIATION AND COMMITMENT TO THE NEPHROGENIC LINEAGE. IN RESPONSE TO THE APPROPRIATE INDUCING SIGNAL, THESE GENES LOSE THEIR REPRESSIVE HISTONE MARKS, WHICH ALLOW FOR THEIR EXPRESSION IN NASCENT NEPHRON PRECURSORS. SUCH KNOWLEDGE OF THE EPIGENETIC LANDSCAPE AND THE RESULTANT CELL FATE OR BEHAVIOR IN THE DEVELOPING KIDNEY WILL GREATLY IMPROVE THE OVERALL SUCCESS IN DESIGNING REGENERATIVE STRATEGIES AND TISSUE REPROGRAMMING METHODOLOGIES FROM PLURIPOTENT CELLS. 2016 15 461 31 ARCHITECTS OF PITUITARY TUMOUR GROWTH. THE PITUITARY IS A MASTER GLAND RESPONSIBLE FOR THE MODULATION OF CRITICAL ENDOCRINE FUNCTIONS. PITUITARY NEUROENDOCRINE TUMOURS (PITNETS) DISPLAY A CONSIDERABLE PREVALENCE OF 1/1106, FREQUENTLY OBSERVED AS BENIGN SOLID TUMOURS. PITNETS STILL REPRESENT A CAUSE OF IMPORTANT MORBIDITY, DUE TO HORMONAL SYSTEMIC DEREGULATION, WITH SURGICAL, RADIOLOGICAL OR CHRONIC TREATMENT REQUIRED FOR ILLNESS MANAGEMENT. THE APPARENT SCARCENESS, UNCOMMON BEHAVIOUR AND MOLECULAR FEATURES OF PITNETS HAVE RESULTED IN A RELATIVELY SLOW PROGRESS IN DEPICTING THEIR PATHOGENESIS. AN APPROPRIATE INTERPRETATION OF DIFFERENT PHENOTYPES OR CELLULAR OUTCOMES DURING TUMOUR GROWTH IS DESIRABLE, SINCE HISTOPATHOLOGICAL CHARACTERIZATION STILL REMAINS THE MAIN OPTION FOR PROGNOSIS ELUCIDATION. IMPROVED KNOWLEDGE OBTAINED IN RECENT DECADES ABOUT PITUITARY TUMORIGENESIS HAS REVEALED THAT THIS PROCESS INVOLVES SEVERAL CELLULAR ROUTES IN ADDITION TO PROLIFERATION AND DEATH, WITH ITS MODULATION DEPENDING ON MANY SIGNALLING PATHWAYS RATHER THAN BEING THE RESULT OF ABNORMALITIES OF A UNIQUE PROLIFERATION PATHWAY, AS SOMETIMES PRESENTED. PITNETS CAN DISPLAY INTRINSIC HETEROGENEITY AND CELL SUBPOPULATIONS WITH DIVERSE BIOLOGICAL, GENETIC AND EPIGENETIC PARTICULARITIES, INCLUDING TUMORIGENIC POTENTIAL. HENCE, TO OBTAIN A BETTER UNDERSTANDING OF PITNET GROWTH NEW APPROACHES ARE REQUIRED AND THE SYSTEMATIZATION OF THE AVAILABLE DATA, WITH THE ROLE OF CELL DEATH PROGRAMS, AUTOPHAGY, STEM CELLS, CELLULAR SENESCENCE, MITOCHONDRIAL FUNCTION, METABOLIC REPROGRAMMING STILL BEING EMERGING FIELDS IN PITUITARY RESEARCH. WE ENVISAGE THAT THROUGH THE COMBINATION OF MOLECULAR, GENETIC AND EPIGENETIC DATA, TOGETHER WITH THE IMPROVED MORPHOLOGICAL, BIOCHEMICAL, PHYSIOLOGICAL AND METABOLICALLY KNOWLEDGE ON PITUITARY NEOPLASTIC POTENTIAL ACCUMULATED IN RECENT DECADES, TUMOUR CLASSIFICATION SCHEMES WILL BECOME MORE ACCURATE REGARDING TUMOUR ORIGIN, BEHAVIOUR AND PLAUSIBLE CLINICAL RESULTS. 2022 16 4204 21 METABOLISM, EPIGENETICS, AND CAUSAL INFERENCE IN HEART FAILURE. EUKARYOTES MUST BALANCE THE METABOLIC AND CELL DEATH ACTIONS OF MITOCHONDRIA VIA CONTROL OF GENE EXPRESSION AND CELL FATE BY CHROMATIN, THEREBY FUNCTIONALLY BINDING THE METABOLOME AND EPIGENOME. THIS INTERACTION HAS FAR-REACHING IMPLICATIONS FOR CHRONIC DISEASES IN HUMANS, THE MOST COMMON OF WHICH ARE THOSE OF THE CARDIOVASCULAR SYSTEM. THE MOST DEVASTATING CONSEQUENCE OF CARDIOVASCULAR DISEASE, HEART FAILURE, IS NOT A SINGLE DISEASE, DIAGNOSIS, OR ENDPOINT. HUMAN AND ANIMAL STUDIES HAVE REVEALED THAT, REGARDLESS OF ETIOLOGY AND SYMPTOMS, HEART FAILURE IS UNIVERSALLY ASSOCIATED WITH ABNORMAL METABOLISM AND GENE EXPRESSION - TO FRAME THIS AS CAUSE OR CONSEQUENCE, HOWEVER, MAY BE TO WRONGFOOT THE QUESTION. THIS ESSAY AIMS TO CHALLENGE CURRENT THINKING ON METABOLIC-EPIGENETIC CROSSTALK IN HEART FAILURE, PRESENTING HYPOTHESES FOR HOW CHRONIC DISEASES ARISE, TAKE HOLD, AND PERSIST. WE UNPACK ASSUMPTIONS ABOUT THE ORDER OF OPERATIONS FOR GENE EXPRESSION AND METABOLISM, EXPLORING RECENT FINDINGS IN NONCARDIAC SYSTEMS THAT LINK METABOLIC INTERMEDIATES DIRECTLY TO CHROMATIN REMODELING. LASTLY, WE DISCUSS POTENTIAL MECHANISMS BY WHICH CHROMATIN MAY SERVE AS A SUBSTRATE FOR METABOLIC MEMORY, AND HOW CHANGES IN CELLULAR TRANSCRIPTOMES (AND HENCE IN CELLULAR BEHAVIOR) IN RESPONSE TO STRESS CORRESPOND TO GLOBAL CHANGES IN CHROMATIN ACCESSIBILITY AND STRUCTURE. 2020 17 2060 11 EPIGENETIC CONTROL OF HAEMATOPOIETIC STEM CELL AGING AND ITS CLINICAL IMPLICATIONS. AGING, CHRONIC INFLAMMATION, AND ENVIRONMENTAL INSULTS PLAY AN IMPORTANT ROLE IN A NUMBER OF DISEASE PROCESSES THROUGH ALTERATIONS OF THE EPIGENOME. IN THIS REVIEW WE EXPLORE HOW AGE-RELATED CHANGES IN THE EPIGENETIC LANDSCAPE CAN AFFECT HETEROGENEITY WITHIN THE HAEMATOPOIETIC STEM CELL (HSC) COMPARTMENT AND THE DERIVING CLINICAL IMPLICATIONS. 2016 18 5281 22 PROMOTION AND SELECTION BY SERUM GROWTH FACTORS DRIVE FIELD CANCERIZATION, WHICH IS ANTICIPATED IN VIVO BY TYPE 2 DIABETES AND OBESITY. INDIVIDUALS SUFFERING FROM TYPE 2 DIABETES OR OBESITY EXHIBIT A SIGNIFICANT INCREASE IN THE INCIDENCE OF VARIOUS TYPES OF CANCER. IT IS GENERALLY ACCEPTED THAT THOSE CONDITIONS ARISE FROM OVERNUTRITION AND A SEDENTARY LIFESTYLE, WHICH LEAD TO INSULIN RESISTANCE CHARACTERIZED BY OVERPRODUCTION OF INSULIN ACTING AS A GROWTH FACTOR. THERE IS A CONSENSUS BASED LARGELY ON EPIDEMIOLOGICAL DATA THAT CHRONIC OVERPRODUCTION OF INSULIN IS RESPONSIBLE FOR THE INCREASED INCIDENCE OF CANCER. A MODEL SYSTEM IN CULTURE OF NIH 3T3 CELLS INDUCES THE COLLECTIVE EFFECTS OF SERUM GROWTH FACTORS ON PROGRESSION THROUGH THE STAGES OF FIELD CANCERIZATION. IT SHOWS THAT THE DRIVING FORCE OF PROGRESSION IS PROMOTION OF CELL GROWTH UNDER SELECTION AT HIGH CELL DENSITY, WITH NO REQUIREMENT FOR EXOGENOUS CARCINOGENIC AGENTS. THE EARLY EFFECT IS GRADUAL SELECTION AMONG MANY PREEXISTING, LOW-PENETRANCE PRENEOPLASTIC MUTATIONS OR STABLE EPIGENETIC VARIANTS, FOLLOWED BY SPORADIC, HIGH-PENETRANCE TRANSFORMING VARIANTS, ALL DEPENDENT ON ENDOGENOUS PROCESSES. THE SIGNIFICANCE OF THE RESULTS FOR CANCER IN DIABETIC AND OBESE INDIVIDUALS IS THAT THE INITIAL STAGES OF THE PROCESS INVOLVE MULTIORGAN METABOLIC INTERACTIONS THAT PRODUCE A SYSTEMIC INSULIN RESISTANCE WITH CHRONIC OVERPRODUCTION OF INSULIN AND LOCALIZED FIELD CANCERIZATION. HYPOMAGNESEMIA IS PREVALENT IN THE FOREGOING METABALO/SYSTEMIC DISORDERS, AND MAY ALSO PROVIDE A SELECTIVE MICROENVIRONMENT FOR TUMOR DEVELOPMENT. 2013 19 6496 37 TRAINED IMMUNITY CONTRIBUTION TO AUTOIMMUNE AND INFLAMMATORY DISORDERS. A DYSREGULATED IMMUNE RESPONSE TOWARD SELF-ANTIGENS CHARACTERIZES AUTOIMMUNE AND AUTOINFLAMMATORY (AIF) DISORDERS. AUTOANTIBODIES OR AUTOREACTIVE T CELLS CONTRIBUTE TO AUTOIMMUNE DISEASES, WHILE AUTOINFLAMMATION RESULTS FROM A HYPER-FUNCTIONAL INNATE IMMUNE SYSTEM. ASIDE FROM THEIR DIFFERENCES, MANY STUDIES SUGGEST THAT MONOCYTES AND MACROPHAGES (MO/MA) SIGNIFICANTLY CONTRIBUTE TO THE DEVELOPMENT OF BOTH TYPES OF DISEASE. MO/MA ARE INNATE IMMUNE CELLS THAT PROMOTE AN IMMUNE-MODULATORY, PRO-INFLAMMATORY, OR REPAIR RESPONSE DEPENDING ON THE MICROENVIRONMENT. HOWEVER, UNDERSTANDING THE CONTRIBUTION OF THESE CELLS TO DIFFERENT IMMUNE DISORDERS HAS BEEN DIFFICULT DUE TO THEIR HIGH FUNCTIONAL AND PHENOTYPIC PLASTICITY. SEVERAL FACTORS CAN INFLUENCE THE FUNCTION OF MO/MA UNDER THE LANDSCAPE OF AUTOIMMUNE/AUTOINFLAMMATORY DISEASES, SUCH AS GENETIC PREDISPOSITION, EPIGENETIC CHANGES, OR INFECTIONS. FOR INSTANCE, SOME VACCINES AND MICROORGANISMS CAN INDUCE EPIGENETIC CHANGES IN MO/MA, MODIFYING THEIR FUNCTIONAL RESPONSES. THIS PHENOMENON IS KNOWN AS TRAINED IMMUNITY. TRAINED IMMUNITY CAN BE MEDIATED BY MO/MA AND NK CELLS INDEPENDENTLY OF T AND B CELL FUNCTION. IT IS DEFINED AS THE ALTERED INNATE IMMUNE RESPONSE TO THE SAME OR DIFFERENT MICROORGANISMS DURING A SECOND ENCOUNTER. THE IMPROVEMENT IN CELL FUNCTION IS RELATED TO EPIGENETIC AND METABOLIC CHANGES THAT MODIFY GENE EXPRESSION. ALTHOUGH THE BENEFITS OF IMMUNE TRAINING HAVE BEEN HIGHLIGHTED IN A VACCINATION CONTEXT, THE EFFECTS OF THIS TYPE OF IMMUNE RESPONSE ON AUTOIMMUNITY AND CHRONIC INFLAMMATION STILL REMAIN CONTROVERSIAL. INDUCTION OF TRAINED IMMUNITY REPROGRAMS CELLULAR METABOLISM IN HEMATOPOIETIC STEM CELLS (HSCS), TRANSMITTING A MEMORY-LIKE PHENOTYPE TO THE CELLS. THUS, TRAINED MO/MA DERIVED FROM HSCS TYPICALLY PRESENT A METABOLIC SHIFT TOWARD GLYCOLYSIS, WHICH LEADS TO THE MODIFICATION OF THE CHROMATIN ARCHITECTURE. DURING TRAINED IMMUNITY, THE EPIGENETIC CHANGES FACILITATE THE SPECIFIC GENE EXPRESSION AFTER SECONDARY CHALLENGE WITH OTHER STIMULI. CONSEQUENTLY, THE ENHANCED PRO-INFLAMMATORY RESPONSE COULD CONTRIBUTE TO DEVELOPING OR MAINTAINING AUTOIMMUNE/AUTOINFLAMMATORY DISEASES. HOWEVER, THE PREDICTION OF THE OUTCOME IS NOT SIMPLE, AND OTHER STUDIES PROPOSE THAT TRAINED IMMUNITY CAN INDUCE A BENEFICIAL RESPONSE BOTH IN AIF AND AUTOIMMUNE CONDITIONS BY INDUCING ANTI-INFLAMMATORY RESPONSES. THIS ARTICLE DESCRIBES THE METABOLIC AND EPIGENETIC MECHANISMS INVOLVED IN TRAINED IMMUNITY THAT AFFECT MO/MA, CONTRAPOSING THE CONTROVERSIAL EVIDENCE ON HOW IT MAY IMPACT AUTOIMMUNE/AUTOINFLAMMATION CONDITIONS. 2022 20 796 24 CELLULAR SENESCENCE IN CANCER: FROM MECHANISMS TO DETECTION. SENESCENCE REFERS TO A CELLULAR STATE FEATURING A STABLE CELL-CYCLE ARREST TRIGGERED IN RESPONSE TO STRESS. THIS RESPONSE ALSO INVOLVES OTHER DISTINCT MORPHOLOGICAL AND INTRACELLULAR CHANGES INCLUDING ALTERATIONS IN GENE EXPRESSION AND EPIGENETIC MODIFICATIONS, ELEVATED MACROMOLECULAR DAMAGE, METABOLISM DEREGULATION AND A COMPLEX PRO-INFLAMMATORY SECRETORY PHENOTYPE. THE INITIAL DEMONSTRATION OF ONCOGENE-INDUCED SENESCENCE IN VITRO ESTABLISHED SENESCENCE AS AN IMPORTANT TUMOUR-SUPPRESSIVE MECHANISM, IN ADDITION TO APOPTOSIS. SENESCENCE NOT ONLY HALTS THE PROLIFERATION OF PREMALIGNANT CELLS BUT ALSO FACILITATES THE CLEARANCE OF AFFECTED CELLS THROUGH IMMUNOSURVEILLANCE. FAILURE TO CLEAR SENESCENT CELLS OWING TO DEFICIENT IMMUNOSURVEILLANCE MAY, HOWEVER, LEAD TO A STATE OF CHRONIC INFLAMMATION THAT NURTURES A PRO-TUMORIGENIC MICROENVIRONMENT FAVOURING CANCER INITIATION, MIGRATION AND METASTASIS. IN ADDITION, SENESCENCE IS A RESPONSE TO POST-THERAPY GENOTOXIC STRESS. THEREFORE, TRACKING THE EMERGENCE OF SENESCENT CELLS BECOMES PIVOTAL TO DETECT POTENTIAL PRO-TUMORIGENIC EVENTS. CURRENT PROTOCOLS FOR THE IN VIVO DETECTION OF SENESCENCE REQUIRE THE ANALYSIS OF FIXED OR DEEP-FROZEN TISSUES, DESPITE A SIGNIFICANT CLINICAL NEED FOR REAL-TIME BIOIMAGING METHODS. ACCURACY AND EFFICIENCY OF SENESCENCE DETECTION ARE FURTHER HAMPERED BY A LACK OF UNIVERSAL AND MORE SPECIFIC SENESCENCE BIOMARKERS. RECENTLY, IN AN ATTEMPT TO OVERCOME THESE HURDLES, AN ASSORTMENT OF DETECTION TOOLS HAS BEEN DEVELOPED. THESE STRATEGIES ALL HAVE SIGNIFICANT POTENTIAL FOR CLINICAL UTILISATION AND INCLUDE FLOW CYTOMETRY COMBINED WITH HISTO- OR CYTOCHEMICAL APPROACHES, NANOPARTICLE-BASED TARGETED DELIVERY OF IMAGING CONTRAST AGENTS, OFF-ON FLUORESCENT SENOPROBES, POSITRON EMISSION TOMOGRAPHY SENOPROBES AND ANALYSIS OF CIRCULATING SASP FACTORS, EXTRACELLULAR VESICLES AND CELL-FREE NUCLEIC ACIDS ISOLATED FROM PLASMA. HERE, WE HIGHLIGHT THE OCCURRENCE OF SENESCENCE IN NEOPLASIA AND ADVANCED TUMOURS, ASSESS THE IMPACT OF SENESCENCE ON TUMORIGENESIS AND DISCUSS HOW THE ONGOING DEVELOPMENT OF SENESCENCE DETECTION TOOLS MIGHT IMPROVE EARLY DETECTION OF MULTIPLE CANCERS AND RESPONSE TO THERAPY IN THE NEAR FUTURE. 2021