1 6733 119 WHAT CAN CHEMICAL CARCINOGENESIS SHED LIGHT ON THE LNT HYPOTHESIS IN RADIATION CARCINOGENESIS? TO PROTECT THE PUBLIC'S HEALTH FROM EXPOSURE TO PHYSICAL, CHEMICAL, AND MICROBIOLOGICAL AGENTS, IT IS IMPORTANT THAT ANY POLICY BE BASED ON RIGOROUS SCIENTIFICALLY BASED RESEARCH. THE CONCEPT OF "LINEAR NO-THRESHOLD" (LNT) HAS BEEN IMPLEMENTED TO PROVIDE GUIDELINE EXPOSURES TO THESE AGENTS. THE PRACTICAL LIMITATION TO TESTING THIS HYPOTHESIS IS TO PROVIDE SUFFICIENT SAMPLES FOR EXPERIMENTAL OR EPIDEMIOLOGICAL STUDIES. WHILE THERE IS NO UNIVERSALLY ACCEPTED UNDERSTANDING OF MOST HUMAN DISEASES, THERE SEEMS TO BE BETTER UNDERSTANDING OF CANCER THAT MIGHT HELP RESOLVE THE "LNT" MODEL. THE PUBLIC'S CONCERN, AFTER BEING EXPOSED TO RADIATION, IS THE POTENTIAL OF PRODUCING CANCER. THE MOST RIGOROUS HYPOTHESIS OF HUMAN CARCINOGENESIS IS THE "MULTISTAGE, MULTIMECHANISM" CHEMICAL CARCINOGENESIS MODEL. THE RADIATION CARCINOGENESIS LNT MODEL, RARELY, IF EVER, BUILT IT INTO THEIR SUPPORT. IT WILL BE ARGUED THAT THIS MULTISTAGE, MULTIMECHANISM MODEL OF CARCINOGENESIS, INVOLVING THE "INITIATION" OF A SINGLE CELL BY A MUTAGEN EVENT, FOLLOWED BY CHRONIC EXPOSURE TO THRESHOLD LEVELS OF EPIGENETIC AGENTS OR CONDITIONS THAT STIMULATE THE CLONAL EXPANSION OF THE "INITIATED" CELL, CAN CONVERT THESE BENIGN CELLS TO BECOME INVASIVE AND METASTATIC. THIS "PROMOTION" PROCESS CAN BE INTERRUPTED, THEREBY PREVENTING THESE INITIATED CELLS FROM TRANSITIONING TO THE "PROGRESSION" PROCESS OF INVASION AND METASTASIS. 2019 2 4018 39 LOW-DOSE IONIZING RADIATION: INDUCTION OF DIFFERENTIAL INTRACELLULAR SIGNALLING POSSIBLY AFFECTING INTERCELLULAR COMMUNICATION. GIVEN THE COMPLEXITY OF THE CARCINOGENIC PROCESS AND THE LACK OF ANY MECHANISTIC UNDERSTANDING OF HOW IONIZING RADIATION AT LOW-LEVEL EXPOSURES AFFECTS THE MULTISTAGE, MULTIMECHANISM PROCESSES OF CARCINOGENESIS, IT IS IMPERATIVE THAT CONCEPTS AND PARADIGMS BE REEXAMINED WHEN EXTRAPOLATING FROM HIGH DOSE TO LOW DOSE. ANY HEALTH EFFECT DIRECTLY LINKED TO LOW-DOSE RADIATION EXPOSURE MUST HAVE MOLECULAR/BIOCHEMICAL AND BIOLOGICAL BASES. ON THE OTHER HAND, DEMONSTRATING SOME MOLECULAR/BIOCHEMICAL OR CELLULAR EFFECT, USING SURROGATE SYSTEMS FOR THE HUMAN BEING, DOES NOT NECESSARILY IMPLY A CORRESPONDING HEALTH EFFECT. GIVEN THE GENERAL ACCEPTANCE OF AN EXTRAPOLATED LNT MODEL, OUR CURRENT UNDERSTANDING OF CARCINOGENESIS CRIES OUT FOR A RESOLUTION OF A REAL PROBLEM. HOW CAN A LOW-LEVEL ACUTE, OR EVEN A CHRONIC, EXPOSURE OF IONIZING RADIATION BRING ABOUT ALL THE DIFFERENT MECHANISMS (MUTAGENIC, CYTOTOXIC, AND EPIGENETIC) AND GENOTYPIC/PHENOTYPIC CHANGES NEEDED TO CONVERT NORMAL CELLS TO AN INVASIVE, MALIGNANT CELL, GIVEN ALL THE PROTECTIVE, REPAIR, AND SUPPRESSIVE SYSTEMS KNOWN TO EXIST IN THE HUMAN BODY? UNTIL RECENTLY, THE PREVAILING PARADIGM THAT IONIZING RADIATION BRINGS ABOUT CANCER PRIMARILY BY DNA DAMAGE AND ITS CONVERSION TO GENE AND CHROMOSOMAL MUTATIONS, DROVE OUR INTERPRETATION OF RADIATION CARCINOGENESIS. TODAY, OUR KNOWLEDGE INCLUDES THE FACTS BOTH THAT EPIGENETIC EVENTS PLAY A MAJOR ROLE IN CARCINOGENESIS AND THAT LOW-DOSE RADIATION CAN ALSO INDUCE EPIGENETIC EVENTS IN AND BETWEEN CELLS IN TISSUES. THIS CHALLENGES ANY SIMPLE EXTRAPOLATION OF THE LNT MODEL. ALTHOUGH A RECENT DELINEATION OF "HALLMARKS" OF THE CANCER PROCESS HAS HELPED TO FOCUS ON HOW IONIZING RADIATION MIGHT CONTRIBUTE TO THE INDUCTION OF CANCERS, SEVERAL OTHER HALLMARKS, PREVIOUSLY IGNORED--NAMELY, THE STEM CELLS IN TISSUES AS TARGETS FOR CARCINOGENESIS AND THE ROLE OF CELL-CELL COMMUNICATION PROCESSES IN MODULATING THE RADIATION EFFECTS ON THE TARGET CELL--MUST BE CONSIDERED, PARTICULARLY FOR THE ADAPTIVE RESPONSE, BYSTANDER EFFECTS, AND GENOMIC INSTABILITY PHENOMENA. 2005 3 6459 22 TIME TO CHANGE FROM A SIMPLE LINEAR MODEL TO A COMPLEX SYSTEMS MODEL. A SIMPLE LINEAR MODEL TO TEST THE HYPOTHESIS BASED ON ONE-ON-ONE RELATIONSHIP HAS BEEN USED TO FIND THE CAUSATIVE FACTORS OF DISEASES. HOWEVER, WE NOW KNOW THAT NOT JUST ONE, BUT MANY FACTORS FROM DIFFERENT SYSTEMS SUCH AS CHEMICAL EXPOSURE, GENES, EPIGENETIC CHANGES, AND PROTEINS ARE INVOLVED IN THE PATHOGENESIS OF CHRONIC DISEASES SUCH AS DIABETES MELLITUS. SO, WITH AVAILABILITY OF MODERN TECHNOLOGIES TO UNDERSTAND THE INTRICATE NATURE OF RELATIONS AMONG COMPLEX SYSTEMS, WE NEED TO MOVE FORWARD TO THE FUTURE BY TAKING COMPLEX SYSTEMS MODEL. 2016 4 1340 31 DESIGNING SAFER DRUGS: (Q)SAR-BASED IDENTIFICATION OF MUTAGENS AND CARCINOGENS. MUTAGENICITY AND CARCINOGENICITY ARE CHRONIC EFFECTS OF PRIMARY CONCERN FOR HUMAN HEALTH. A UNIFYING APPROACH TO THEIR MECHANISTIC UNDERSTANDING IS THE RECOGNITION THAT MANY CHEMICALS PROVOKE BOTH EFFECTS BY ELECTROPHILIC ATTACK TO THE BIOLOGICAL MACROMOLECULES, AS SUCH OR AFTER METABOLISM (GENOTOXIC CARCINOGENICITY). QSARS OF INDIVIDUAL CLASSES OF GENOTOXIC CARCINOGENS HAVE CONTRIBUTED TO THE ELUCIDATION OF THE CHEMICAL DETERMINANTS OF THIS ACTIVITY. LITTLE WORK HAS BEEN DONE ON THE EPIGENETIC CARCINOGENS, ACTING THROUGH NON-GENOTOXIC, VERY SPECIFIC MECHANISMS. HOWEVER, THE EXISTING QSARS FOR INDIVIDUAL CHEMICAL CLASSES ARE TOO FEW TO BE OF REAL USEFULNESS IN THE SCREENING OF MASSES OF CANDIDATE DRUGS. MODELS FOR PREDICTING THE CARCINOGENICITY OF "ANY TYPE" OF CHEMICALS HAVE BEEN PROPOSED: PROSPECTIVE PREDICTION EXERCISES POINTED TO THE SERIOUS LIMITATIONS OF MOST OF THESE APPROACHES. THE BEST ALTERNATIVE IS PROVIDED BY PANELS OF HUMAN EXPERTS. THE ABOVE PREDICTION EXERCISES CONSIDERED SAMPLES OF GENERAL CHEMICALS, THUS WE SPECIFICALLY ADDRESSED IN THIS PAPER THE ISSUE OF PHARMACEUTICAL DRUGS. WE APPLIED OUR EXPERT KNOWLEDGE TO A DATABASE OF DRUGS WHOSE CARCINOGENICITY/NONCARCINOGENICITY STATUS WAS KNOWN. WHEREAS MOST OF THE NONCARCINOGENS WERE CORRECTLY IDENTIFIED, OUR PREDICTION OF CARCINOGENS WAS LESS SUCCESSFUL THAN WITH THE GENERAL CHEMICALS. SEVERAL CARCINOGENIC DRUGS DID NOT SHOW RECOGNIZED STRUCTURAL ALERTS, AND SUPPOSEDLY ACTED BY EPIGENETIC MECHANISMS. WHEREAS THE CONTRIBUTION OF HUMAN EXPERTS IS HIGHLY VALUABLE IN THIS PHASE (E.G. PRIORITY SETTING), MORE WORK IS NECESSARY ON: A) EPIGENETIC CARCINOGENS; B) EFFICIENT COMPUTERIZED MODELS. 2003 5 266 37 ADVERSE OUTCOME PATHWAYS FOR IONIZING RADIATION AND BREAST CANCER INVOLVE DIRECT AND INDIRECT DNA DAMAGE, OXIDATIVE STRESS, INFLAMMATION, GENOMIC INSTABILITY, AND INTERACTION WITH HORMONAL REGULATION OF THE BREAST. KNOWLEDGE ABOUT ESTABLISHED BREAST CARCINOGENS CAN SUPPORT IMPROVED AND MODERNIZED TOXICOLOGICAL TESTING METHODS BY IDENTIFYING KEY MECHANISTIC EVENTS. IONIZING RADIATION (IR) INCREASES THE RISK OF BREAST CANCER, ESPECIALLY FOR WOMEN AND FOR EXPOSURE AT YOUNGER AGES, AND EVIDENCE OVERALL SUPPORTS A LINEAR DOSE-RESPONSE RELATIONSHIP. WE USED THE ADVERSE OUTCOME PATHWAY (AOP) FRAMEWORK TO OUTLINE AND EVALUATE THE EVIDENCE LINKING IONIZING RADIATION WITH BREAST CANCER FROM MOLECULAR INITIATING EVENTS TO THE ADVERSE OUTCOME THROUGH INTERMEDIATE KEY EVENTS, CREATING A QUALITATIVE AOP. WE IDENTIFIED KEY EVENTS BASED ON REVIEW ARTICLES, SEARCHED PUBMED FOR RECENT LITERATURE ON KEY EVENTS AND IR, AND IDENTIFIED ADDITIONAL PAPERS USING REFERENCES. WE MANUALLY CURATED PUBLICATIONS AND EVALUATED DATA QUALITY. IONIZING RADIATION DIRECTLY AND INDIRECTLY CAUSES DNA DAMAGE AND INCREASES PRODUCTION OF REACTIVE OXYGEN AND NITROGEN SPECIES (RONS). RONS LEAD TO DNA DAMAGE AND EPIGENETIC CHANGES LEADING TO MUTATIONS AND GENOMIC INSTABILITY (GI). PROLIFERATION AMPLIFIES THE EFFECTS OF DNA DAMAGE AND MUTATIONS LEADING TO THE AO OF BREAST CANCER. SEPARATELY, RONS AND DNA DAMAGE ALSO INCREASE INFLAMMATION. INFLAMMATION CONTRIBUTES TO DIRECT AND INDIRECT EFFECTS (EFFECTS IN CELLS NOT DIRECTLY REACHED BY IR) VIA POSITIVE FEEDBACK TO RONS AND DNA DAMAGE, AND SEPARATELY INCREASES PROLIFERATION AND BREAST CANCER THROUGH PRO-CARCINOGENIC EFFECTS ON CELLS AND TISSUE. FOR EXAMPLE, GENE EXPRESSION CHANGES ALTER INFLAMMATORY MEDIATORS, RESULTING IN IMPROVED SURVIVAL AND GROWTH OF CANCER CELLS AND A MORE HOSPITABLE TISSUE ENVIRONMENT. ALL OF THESE EVENTS OVERLAP AT MULTIPLE POINTS WITH EVENTS CHARACTERISTIC OF "BACKGROUND" INDUCTION OF BREAST CARCINOGENESIS, INCLUDING HORMONE-RESPONSIVE PROLIFERATION, OXIDATIVE ACTIVITY, AND DNA DAMAGE. THESE OVERLAPS MAKE THE BREAST PARTICULARLY SUSCEPTIBLE TO IONIZING RADIATION AND REINFORCE THAT THESE BIOLOGICAL ACTIVITIES ARE IMPORTANT CHARACTERISTICS OF CARCINOGENS. AGENTS THAT INCREASE THESE BIOLOGICAL PROCESSES SHOULD BE CONSIDERED POTENTIAL BREAST CARCINOGENS, AND PREDICTIVE METHODS ARE NEEDED TO IDENTIFY CHEMICALS THAT INCREASE THESE PROCESSES. TECHNIQUES ARE AVAILABLE TO MEASURE RONS, DNA DAMAGE AND MUTATION, CELL PROLIFERATION, AND SOME INFLAMMATORY PROTEINS OR PROCESSES. IMPROVED ASSAYS ARE NEEDED TO MEASURE GI AND CHRONIC INFLAMMATION, AS WELL AS THE INTERACTION WITH HORMONALLY DRIVEN DEVELOPMENT AND PROLIFERATION. SEVERAL METHODS MEASURE DIVERSE EPIGENETIC CHANGES, BUT IT IS NOT CLEAR WHICH CHANGES ARE RELEVANT TO BREAST CANCER. IN ADDITION, MOST TOXICOLOGICAL ASSAYS ARE NOT CONDUCTED IN MAMMARY TISSUE, AND SO IT IS A PRIORITY TO EVALUATE IF RESULTS FROM OTHER TISSUES ARE GENERALIZABLE TO BREAST, OR TO CONDUCT ASSAYS IN BREAST TISSUE. DEVELOPING AND APPLYING THESE ASSAYS TO IDENTIFY EXPOSURES OF CONCERN WILL FACILITATE EFFORTS TO REDUCE SUBSEQUENT BREAST CANCER RISK. 2020 6 3418 35 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 7 389 31 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 8 761 32 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 9 6655 28 UPDATE ON THE MOLECULAR PATHOLOGY OF CUTANEOUS SQUAMOUS CELL CARCINOMA. CUTANEOUS SQUAMOUS CELL CARCINOMA (CSCC) IS THE SECOND MOST COMMON SKIN CANCER, ORIGINATING FROM KERATINOCYTES OF THE SPINOUS LAYER. NUMEROUS RISK FACTORS HAVE BEEN DISCOVERED FOR THE INITIATION AND GROWTH OF THIS TYPE OF CANCER, SUCH AS EXPOSURE TO UV AND IONIZING RADIATION, CHEMICAL CARCINOGENS, THE PRESENCE OF IMMUNOSUPPRESSION STATES, CHRONIC INFLAMMATION, INFECTIONS WITH HIGH-RISK VIRAL STRAINS, AND, LAST BUT NOT LEAST, THE PRESENCE OF DISEASES ASSOCIATED WITH GENETIC ALTERATIONS. THE IMPORTANT SOCIO-ECONOMIC IMPACT, AS WELL AS THE DIFFICULTY ASSOCIATED WITH THERAPY FOR ADVANCED FORMS, HAS MADE THE MOLECULAR MECHANISMS UNDERLYING THIS NEOPLASIA MORE AND MORE INTENSIVELY STUDIED, WITH THE INTENTION OF ACHIEVING A BETTER UNDERSTANDING AND ADVANCING THE TREATMENT OF THIS PATHOLOGY. THIS REVIEW AIMS TO PROVIDE A BRIEF FORAY INTO THE MOLECULAR, GENETIC, AND EPIGENETIC ASPECTS OF THIS CANCER, AS WELL AS THE TREATMENT METHODS, RANGING FROM THE FIRST USED TO THE LATEST TARGETED THERAPIES. 2023 10 705 32 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 11 3406 32 HOW THE IMMUNE SYSTEM RESPONDS TO ALLERGY IMMUNOTHERAPY. IGE-MEDIATED DISEASES REPRESENT A HIGHLY DIVERSIFIED AND MULTIFACTORIAL GROUP OF DISORDERS THAT CAN DEEPLY IMPACT THE PATIENTS' QUALITY OF LIFE. CURRENTLY, ALLERGY IMMUNOTHERAPY (AIT) STILL REMAINS THE GOLD STANDARD FOR THE MANAGEMENT OF SUCH PATHOLOGIES. IN THIS REVIEW, WE COMPREHENSIVELY EXAMINE AND DISCUSS HOW AIT CAN AFFECT BOTH THE INNATE AND THE ADAPTIVE IMMUNE RESPONSES AT DIFFERENT CELL LEVELS AND PROPOSE TIMING-SCHEDULED ALTERATIONS INDUCED BY AIT BY HYPOTHESIZING FIVE SEQUENTIAL PHASES: AFTER THE DESENSITIZATION OF EFFECTOR NON-LYMPHOID CELLS AND A TRANSIENT INCREASE OF IGE (PHASE 1), HIGH DOSES OF ALLERGEN GIVEN BY AIT STIMULATE THE SHIFT FROM TYPE 2/TYPE 3 TOWARDS TYPE 1 RESPONSE (PHASE 2), WHICH IS PROGRESSIVELY POTENTIATED BY THE INCREASE OF IFN-GAMMA THAT PROMOTES THE CHRONIC ACTIVATION OF APCS, PROGRESSIVELY LEADING TO THE HYPEREXPRESSION OF NOTCH1L (DELTA4) AND THE SECRETION OF IL-12 AND IL-27, WHICH ARE ESSENTIAL TO ACTIVATE IL-10 GENE IN TH1 AND ILC1 CELLS. AS CONSEQUENCE, AN EXPANSION OF CIRCULATING MEMORY TH1/TR1 CELLS AND ILC-REG CHARACTERIZES THE THIRD PHASE ADDRESSED TO ANTAGONIZE/BALANCE THE EXCESS OF TYPE 1 RESPONSE (PHASE 3). THE PROGRESSIVE INCREASE OF IL-10 TRIGGERS A NUMBER OF REGULATORY CIRCUITS SUSTAINED BY INNATE AND ADAPTIVE IMMUNE CELLS AND FAVORING T-CELL TOLERANCE (PHASE 4), WHICH MAY ALSO BE MAINTAINED FOR A LONG PERIOD AFTER AIT INTERRUPTION (PHASE 5). DIFFERENT ADMINISTRATION APPROACHES OF AIT HAVE SHOWN A SIMILAR TAILORING OF THE IMMUNE RESPONSES AND CAN BE MONITORED BY TIMELY, OPTIMIZED BIOMARKERS. THE CLINICAL FAILURE OF THIS TREATMENT CAN OCCUR, AND MANY GENETIC/EPIGENETIC POLYMORPHISMS/MUTATIONS INVOLVING SEVERAL IMMUNOLOGICAL MECHANISMS, SUCH AS THE PLASTICITY OF IMMUNE RESPONSES AND THE INDUCTION/MAINTENANCE OF REGULATORY CIRCUITS, HAVE BEEN DESCRIBED. THE KNOWLEDGE OF HOW AIT CAN SHAPE THE IMMUNE SYSTEM AND ITS RESPONSES IS A KEY TOOL TO DEVELOP NOVEL AIT STRATEGIES INCLUDING THE ENGINEERING OF ALLERGEN OR THEIR EPITOPES. WE NOW HAVE THE POTENTIAL TO UNDERSTAND THE PRECISE CAUSES OF AIT FAILURE AND TO ESTABLISH THE BEST BIOMARKERS OF AIT EFFICACY IN EACH PHASE OF THE TREATMENT. 2022 12 5029 30 PERSPECTIVES ON MICROBES AS ONCOGENIC INFECTIOUS AGENTS AND IMPLICATIONS FOR BREAST CANCER. CANCER MANAGEMENT IS PARTLY BASED ON WEIGHING RISK FACTORS ATTRIBUTED TO NONINFECTIOUS AGENTS, HUMAN GENES AND EPIGENETIC FACTORS. INFECTIOUS DISEASE CAUSATION HAS LARGELY BEEN RESTRICTED TO GENES DIRECTLY RESPONSIBLE FOR CAUSING CANCER AFTER SUSTAINING DAMAGE I.E. ONCOGENES. LATELY, EVIDENCE HAS EMERGED LINKING INFECTIOUS AGENTS TO A NUMBER OF CHRONIC DISEASES. THESE STUDIES HAVE RECOGNIZED THE INFLUENCE THAT ACUTE, ATYPICAL, LATENT AND CHRONIC INFECTIONS MAY PLAY IN TRICKING THE IMMUNE SYSTEM AND AFFECTING DISEASE ETIOLOGY. SIMILAR EVIDENCE IS EMERGING IN MODEL SYSTEMS WITH RESPECT TO THE ROLE OF INFECTIOUS AGENTS IN GASTROINTESTINAL, LIVER AND LUNG CANCERS. ALTHOUGH VIRUSES HAVE BEEN FOUND IN ASSOCIATION WITH BREAST CANCER, SKEPTICISM REMAINS ABOUT A ROLE FOR OTHER INFECTIOUS AGENTS, NOTABLY MICROBES IN THE DISEASE ETIOLOGY. IMPROVED EXPERIMENTAL DESIGNS EMPLOYED IN DIFFERENT CANCER STUDIES AND A LESS RIGID DEFINITION OF INFECTIOUS CAUSATION MAY AID IN CONFIRMING OR REFUTING A MICROBE-BREAST CANCER CONNECTION. CANCER RECURRENCE COULD POTENTIALLY BE MINIMIZED AND TREATMENT OPTIONS FURTHER TAILORED ON A CASE BY CASE BASIS IF MICROBES/MICROBIAL COMPONENTS/STRAIN VARIANTS ASSOCIATED WITH BREAST CANCER ARE IDENTIFIED; PROBIOTICS ARE EMPLOYED TO REDUCE TREATMENT SIDE-EFFECTS AND IF MICROBES COULD EFFECTIVELY BE HARNESSED IN IMMUNOTHERAPY. 2008 13 1844 34 EFFECTS OF THE LIFESTYLE HABITS IN BREAST CANCER TRANSCRIPTIONAL REGULATION. THROUGH RESEARCH CARRIED OUT IN THE LAST 25 YEARS ABOUT THE BREAST CANCER ETIOLOGY, IT HAS BEEN POSSIBLE TO ESTIMATE THAT LESS THAN 10 % OF PATIENTS WHO ARE DIAGNOSED WITH THE CONDITION ARE CARRIERS OF SOME GERMLINE OR SOMATIC MUTATION. THE CLINICAL REPORTS OF BREAST CANCER PATIENTS WITH HEALTHY TWINS AND THE DEVELOPMENT OF DISEASE IN WOMEN WITHOUT HIGH PENETRANCE MUTATIONS DETECTED, WARN THE PARTICIPATION MORE FACTORS IN THE TRANSFORMATION PROCESS. THE HIGH INCIDENCE OF MAMMARY ADENOCARCINOMA IN THE MODERN WOMAN AND THE URGENT NEED FOR NEW METHODS OF PREVENTION AND EARLY DETECTION HAVE DEMANDED MORE INFORMATION ABOUT THE ROLE THAT ENVIRONMENT AND LIFESTYLE HAVE ON THE TRANSFORMATION OF MAMMARY GLAND EPITHELIAL CELLS. OBESITY, ALCOHOLISM AND SMOKING ARE FACTORS THAT HAVE SHOWN A CLOSE CORRELATION WITH THE RISK OF DEVELOPING BREAST CANCER. AND ALTHOUGH THESE CONDITIONS AFFECT DIFFERENT CELL REGULATION LEVELS, THE STUDY OF ITS EFFECTS IN THE MECHANISMS OF TRANSCRIPTIONAL AND EPIGENETIC REGULATION IS CONSIDERED CRITICAL FOR A BETTER UNDERSTANDING OF THE LOSS OF IDENTITY OF EPITHELIAL CELLS DURING CARCINOGENESIS OF THIS TISSUE. THE MAIN OBJECTIVE OF THIS REVIEW WAS TO ESTABLISH THE IMPORTANCE OF CHANGES OCCURRING TO TRANSCRIPTIONAL LEVEL IN THE MAMMARY GLAND AS A CONSEQUENCE OF ACUTE OR CHRONIC EXPOSURE TO HARMFUL PRODUCTS SUCH AS OBESITY-CAUSING FOODS, ETHANOL AND CIGARETTE SMOKE COMPONENTS. AT ANALYZE THE MAIN STUDIES RELATED TO TOPIC, IT HAS CONCLUDED THAT THE UNDERSTANDING OF EFFECTS CAUSED BY THE LIFESTYLE FACTORS IN PERFORMANCE OF THE TRANSCRIPTIONAL MECHANISMS THAT DETERMINE GENE EXPRESSION OF THE MAMMARY GLAND EPITHELIAL CELLS, MAY HELP EXPLAIN THE DEVELOPMENT OF THIS DISEASE IN WOMEN WITHOUT GENETIC PROPENSITY AND DIFFERENT PHENOTYPIC MANIFESTATIONS OF THIS CANCER TYPE. 2016 14 6809 24 [EPIGENETICS IN INFLAMMATORY SYSTEMIC DISEASES]. IN ADDITION TO ANALYSIS OF THE GENETIC CODE, IN RECENT YEARS MORE AND MORE STUDIES HAVE CONCENTRATED ON CHANGES IN THE EPIGENETIC CODE. EPIGENETIC MECHANISMS DETERMINE WHICH GENES IN A CELL ARE TRANSCRIBED AND THUS FORM THE PHENOTYPE OF A CELL. THE EPIGENETIC CODE CAN BE CHANGED BY ENVIRONMENTAL INFLUENCES, WHICH ALLOWS CELLS TO ADAPT TO LONGSTANDING CHANGES IN THE ENVIRONMENT. THEREFORE, IT IS FEASIBLE TO ASSUME THAT EPIGENETIC CHANGES ARE THE MOLECULAR BASIS FOR LONG-TERM EFFECTS OF THE ENVIRONMENT ON DISEASE DEVELOPMENT. IN PARTICULAR IN TUMORS AND CHRONIC INFLAMMATORY DISEASES EPIGENETIC CHANGES WERE FOUND TO CORRELATE WITH DISEASE SEVERITY AND PROGRESSION. KNOWLEDGE ABOUT THESE EPIGENETIC CHANGES MIGHT HELP THAT EPIGENETIC MODIFICATIONS CAN BE USED IN THE FUTURE AS BIOMARKERS, PROGNOSTIC FACTORS AND THERAPEUTIC TARGETS. 2014 15 2901 32 GENDER DIFFERENCES IN GERM-CELL MUTAGENESIS AND GENETIC RISK. CURRENT INTERNATIONAL CLASSIFICATION SYSTEMS FOR CHEMICAL MUTAGENS ARE HAZARD-BASED RATHER THAN AIMED AT ASSESSING RISKS QUANTITATIVELY. IN THE PAST, GERM-CELL TESTS HAVE BEEN MAINLY PERFORMED WITH A LIMITED NUMBER OF SOMATIC CELL MUTAGENS, AND RARELY UNDER CONDITIONS AIMED AT COMPARING GENDER-SPECIFIC DIFFERENCES IN SUSCEPTIBILITY TO MUTAGEN EXPOSURES. THERE ARE PROFOUND DIFFERENCES IN THE GENETIC CONSTITUTION, AND IN HORMONAL, STRUCTURAL, AND FUNCTIONAL ASPECTS OF DIFFERENTIATION AND CONTROL OF GAMETOGENESIS BETWEEN THE SEXES. A CRITICAL REVIEW OF THE LITERATURE SUGGESTS THAT THESE DIFFERENCES MAY HAVE A PROFOUND IMPACT ON THE RELATIVE SUSCEPTIBILITY, STAGE OF HIGHEST SENSITIVITY AND THE RELATIVE RISK FOR THE GENESIS OF GENE MUTATION, AS WELL AS STRUCTURAL AND NUMERICAL CHROMOSOMAL ABERRATIONS IN MALE AND FEMALE GERM CELLS. TRANSMISSION OF GERM-CELL MUTATIONS TO THE OFFSPRING MAY ALSO ENCOUNTER GENDER-SPECIFIC INFLUENCES. GENDER DIFFERENCES IN SUSCEPTIBILITY TO CHEMICALLY DERIVED ALTERATIONS IN IMPRINTING PATTERNS MAY POSE A THREAT FOR THE HEALTH OF THE OFFSPRING AND MAY ALSO BE TRANSMITTED TO FUTURE GENERATIONS. RECENT REPORTS ON DIFFERENT GENETIC EFFECTS FROM HIGH ACUTE AND FROM CHRONIC LOW-DOSE EXPOSURES CHALLENGE THE VALIDITY OF CONCLUSIONS DRAWN FROM STANDARD METHODS OF MUTAGENICITY TESTING. IN CONCLUSION, RESEARCH IS URGENTLY NEEDED TO IDENTIFY GENETIC HAZARDS FOR A LARGER RANGE OF CHEMICAL COMPOUNDS, INCLUDING THOSE SUSPECTED TO DISTURB PROPER CHROMOSOME SEGREGATION. ALTERATIONS IN EPIGENETIC PROGRAMMING AND THEIR HEALTH CONSEQUENCES WILL HAVE TO BE INVESTIGATED. MORE ATTENTION SHOULD BE PAID TO GENDER-SPECIFIC GENETIC EFFECTS. FINALLY, THE DATABASE FOR GERM-CELL MUTAGENS SHOULD BE ENLARGED USING MOLECULAR METHODOLOGIES, AND GENETIC EPIDEMIOLOGY STUDIES SHOULD BE PERFORMED WITH THESE TECHNIQUES TO VERIFY HUMAN GENETIC RISK. 2007 16 2136 29 EPIGENETIC INFLUENCES IN THE OBESITY/COLORECTAL CANCER AXIS: A NOVEL THERAGNOSTIC AVENUE. THE WORLD HEALTH ORGANIZATION (WHO) CONSIDERS THAT OBESITY HAS REACHED PROPORTIONS OF PANDEMIC. EXPERTS ALSO INSIST ON THE IMPORTANCE OF CONSIDERING OBESITY AS A CHRONIC DISEASE AND ONE OF THE MAIN CONTRIBUTORS TO THE WORLDWIDE BURDEN OF OTHER NONTRANSMISSIBLE CHRONIC DISEASES, WHICH HAVE A GREAT IMPACT ON HEALTH, LIFESTYLE, AND ECONOMIC COST. ONE OF THE MOST CURRENT CHALLENGES OF BIOMEDICAL SCIENCE FACES IS TO UNDERSTAND THE ORIGIN OF THE CHRONIC NONTRANSMISSIBLE DISEASES, SUCH AS OBESITY AND CANCER. THERE IS A LARGE EVIDENCE, BOTH IN EPIDEMIOLOGICAL STUDIES IN HUMANS AND IN ANIMAL MODELS, OF THE ASSOCIATION BETWEEN OBESITY AND AN INCREASED RISK OF CANCER INCIDENCE. IN THE LAST YEARS, THE INITIAL DISCOVERY OF EPIGENETIC MECHANISMS REPRESENTS THE MOST RELEVANT FINDING TO EXPLAIN HOW THE GENOME INTERACTS WITH ENVIRONMENTAL FACTORS AND THE RIPPLE EFFECTS ON DISEASE PATHOGENESES. SINCE THEN, ALL EPIGENETIC PROCESS HAS BEEN INVESTIGATED BY THE SCIENTIFIC COMMUNITIES FOR NEARLY TWO DECADES TO DETERMINE WHICH COMPONENTS ARE INVOLVED IN THIS PROCESS. DNA/RNA METHYLATION AND MIRNA ARE CLASSIFIED AS TWO OF THE MOST IMPORTANT REPRESENTATIVE CLASSES OF SUCH EPIGENETIC MECHANISMS AND DYSREGULATED ACTIVITY OF SUCH MECHANISM CAN CERTAINLY CONTRIBUTE TO DISEASE PATHOGENESIS AND/OR PROGRESSION ESPECIALLY IN TUMORS. THIS REVIEW ARTICLE SERVES TO HIGHLIGHT THE IMPACT OF DNA/RNA METHYLATION AND MIRNA-BASED EPIGENETIC MECHANISM ACTIVITIES IN THE INTERPLAY BETWEEN OBESITY AND THE DEVELOPMENT AND CLINICAL SIGNIFICANCE OF COLORECTAL CANCER. 2019 17 3404 29 HOW EPIGENETICS IMPACTS ON HUMAN DISEASES. EPIGENETICS IS A RAPIDLY GROWING FIELD OF BIOLOGY THAT STUDIES THE CHANGES IN GENE EXPRESSION THAT ARE NOT DUE TO ALTERATIONS IN THE DNA SEQUENCE BUT RATHER THE CHEMICAL MODIFICATIONS OF DNA AND ITS ASSOCIATED PROTEINS. EPIGENETIC MECHANISMS CAN PROFOUNDLY INFLUENCE GENE EXPRESSION, CELL DIFFERENTIATION, TISSUE DEVELOPMENT, AND DISEASE SUSCEPTIBILITY. UNDERSTANDING EPIGENETIC CHANGES IS ESSENTIAL TO ELUCIDATE THE MECHANISMS UNDERLYING THE INCREASINGLY RECOGNIZED ROLE OF ENVIRONMENTAL AND LIFESTYLE FACTORS IN HEALTH AND DISEASE AND THE INTERGENERATIONAL TRANSMISSION OF PHENOTYPES. RECENT STUDIES SUGGEST EPIGENETICS MAY BE CRITICAL IN VARIOUS DISEASES, FROM CARDIOVASCULAR DISEASE AND CANCER TO NEURODEVELOPMENTAL AND NEURODEGENERATIVE DISORDERS. EPIGENETIC MODIFICATIONS ARE POTENTIALLY REVERSIBLE AND COULD PROVIDE NEW THERAPEUTIC AVENUES FOR TREATING THESE DISEASES USING EPIGENETIC MODULATORS. MOREOVER, EPIGENETICS PROVIDE INSIGHT INTO DISEASE PATHOGENESIS AND BIOMARKERS FOR DISEASE DIAGNOSIS AND RISK STRATIFICATION. NEVERTHELESS, EPIGENETIC INTERVENTIONS HAVE THE POTENTIAL FOR UNINTENDED CONSEQUENCES AND MAY POTENTIALLY LEAD TO INCREASED RISKS OF UNEXPECTED OUTCOMES, SUCH AS ADVERSE DRUG REACTIONS, DEVELOPMENTAL ABNORMALITIES, AND CANCER. THEREFORE, RIGOROUS STUDIES ARE ESSENTIAL TO MINIMIZE THE RISKS ASSOCIATED WITH EPIGENETIC THERAPIES AND TO DEVELOP SAFE AND EFFECTIVE INTERVENTIONS FOR IMPROVING HUMAN HEALTH. THIS ARTICLE PROVIDES A SYNTHETIC AND HISTORICAL VIEW OF THE ORIGIN OF EPIGENETICS AND SOME OF THE MOST RELEVANT ACHIEVEMENTS. 2023 18 5290 22 PROSTATE CANCER PREVENTION: AGENT DEVELOPMENT STRATEGIES. DESPITE ADVANCES IN SURGERY, RADIATION, AND MEDICAL THERAPY OVER THE PAST DECADE AND THE WIDESPREAD ADOPTION OF PSA SCREENING, PROSTATE CANCER CONTINUES TO BE THE SECOND LEADING CAUSE OF CANCER DEATH IN MEN IN THE UNITED STATES. INVASIVE CANCER IS THE END RESULT OF CARCINOGENESIS, A CHRONIC PROCESS OCCURRING OVER MANY YEARS DRIVEN BY GENETIC AND EPIGENETIC ALTERATIONS. THE PROTRACTED NATURE OF THIS TRANSFORMATION TO THE MALIGNANT PHENOTYPE PROVIDES AN OPPORTUNITY TO INTERVENE PHARMACOLOGICALLY TO PREVENT, REVERSE, OR DELAY CARCINOGENESIS, I.E. CHEMOPREVENTION. HEREIN, WE DESCRIBE THE UNIQUE FEATURES OF CANCER PREVENTION, AS OPPOSED TO CANCER TREATMENT, AGENT DEVELOPMENT CLINICAL TRIALS, AND PROVIDE A SUMMARY OF THE ONGOING RESEARCH IN THIS FIELD BEING SUPPORTED BY THE NATIONAL CANCER INSTITUTE. 2014 19 2049 22 EPIGENETIC CODE AND POTENTIAL EPIGENETIC-BASED THERAPIES AGAINST CHRONIC DISEASES IN DEVELOPMENTAL ORIGINS. ACCUMULATED FINDINGS HAVE DEMONSTRATED THAT THE EPIGENETIC CODE PROVIDES A POTENTIAL LINK BETWEEN PRENATAL STRESS AND CHANGES IN GENE EXPRESSION THAT COULD BE INVOLVED IN THE DEVELOPMENTAL PROGRAMMING OF VARIOUS CHRONIC DISEASES IN LATER LIFE. MEANWHILE, BASED ON THE FACT THAT EPIGENETIC MODIFICATIONS ARE REVERSIBLE AND CAN BE MANIPULATED, THIS PROVIDES A UNIQUE CHANCE TO DEVELOP MULTIPLE NOVEL EPIGENETIC-BASED THERAPEUTIC STRATEGIES AGAINST MANY CHRONIC DISEASES IN EARLY DEVELOPMENTAL PERIODS. THIS ARTICLE WILL GIVE A SHORT REVIEW OF RECENT FINDINGS OF PRENATAL INSULT-INDUCED EPIGENETIC CHANGES IN DEVELOPMENTAL ORIGINS OF SEVERAL CHRONIC DISEASES, AND WILL ATTEMPT TO PROVIDE AN OVERVIEW OF THE CURRENT EPIGENETIC-BASED STRATEGIES APPLIED IN THE EARLY PREVENTION, DIAGNOSIS AND POSSIBLE THERAPIES FOR HUMAN CHRONIC DISEASES. 2014 20 6905 22 [THE ROLE OF EPIGENETIC REGULATIONS IN EARLY CHILDHOOD DISEASES]. WITH THE ACCEPTANCE OF "THE DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE" CONCEPT IN THE 1990S, IT BECAME CLEAR THAT EPIGENETIC INHERITANCE, WHICH DO NOT INVOLVE CHANGES IN THE DNA SEQUENCE HAS IMPORTANT ROLE IN THE PATHOGENESIS OF DISEASES. EPIGENETIC REGULATION SERVES THE ADAPTATION TO THE CHANGING ENVIRONMENT AND MAINTAINS THE REPRODUCTIVE FITNESS EVEN ON THE DRAWBACK OF INCREASED RISK OF DISEASES IN LATER LIFE. THE ROLE OF EPIGENETIC MECHANISMS IN CHRONIC NON-COMMUNICABLE DISEASES HAS BEEN WELL ESTABLISHED. RECENT STUDIES HAVE REVEALED THAT EPIGENETIC CHANGES HAVE ALSO CAUSAL ROLE IN CERTAIN PEDIATRIC DISEASES. THE REVIEW EVALUATES THE RECENT EPIGENETIC FINDINGS IN THE PATHOMECHANISM OF COMMON PEDIATRIC DISEASES. THE WIDE RANGE AND LONG-LASTING DURATION OF EPIGENETIC REGULATIONS GIVE IMPORTANCE TO THE SUBJECT. METHODS ARE ALREADY AVAILABLE TO EVALUATE A PART OF THE EPIGENETIC CHANGES IN THE CLINICAL PRACTICE, PRESENTLY AIMING PRIMARILY THE ESTIMATION OF THE DISEASE RISK OR DEFINITION OF DIAGNOSIS. FURTHERMORE, THERE ARE ALREADY AVAILABLE LIMITED MEANS TO INFLUENCE THE EPIGENETIC REGULATION. 2019