1 1844 153 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 2 6809 39 [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 3 738 38 CANCER SUSCEPTIBILITY: EPIGENETIC MANIFESTATION OF ENVIRONMENTAL EXPOSURES. CANCER IS A DISEASE THAT RESULTS FROM BOTH GENETIC AND EPIGENETIC CHANGES. DISCORDANT PHENOTYPES AND VARYING INCIDENCES OF COMPLEX DISEASES SUCH AS CANCER IN MONOZYGOTIC TWINS AS WELL AS GENETICALLY IDENTICAL LABORATORY ANIMALS HAVE LONG BEEN ATTRIBUTED TO DIFFERENCES IN ENVIRONMENTAL EXPOSURES. ACCUMULATING EVIDENCE INDICATES, HOWEVER, THAT DISPARITIES IN GENE EXPRESSION RESULTING FROM VARIABLE MODIFICATIONS IN DNA METHYLATION AND CHROMATIN STRUCTURE IN RESPONSE TO THE ENVIRONMENT ALSO PLAY A ROLE IN DIFFERENTIAL SUSCEPTIBILITY TO DISEASE. DESPITE A GROWING CONSENSUS ON THE IMPORTANCE OF EPIGENETICS IN THE ETIOLOGY OF CHRONIC HUMAN DISEASES, THE GENES MOST PRONE TO EPIGENETIC DYSREGULATION ARE INCOMPLETELY DEFINED. MOREOVER, NEITHER THE ENVIRONMENTAL AGENTS MOST STRONGLY AFFECTING THE EPIGENOME NOR THE CRITICAL WINDOWS OF VULNERABILITY TO ENVIRONMENTALLY INDUCED EPIGENETIC ALTERATIONS ARE ADEQUATELY CHARACTERIZED. THESE MAJOR DEFICITS IN KNOWLEDGE MARKEDLY IMPAIR OUR ABILITY TO UNDERSTAND FULLY THE ETIOLOGY OF CANCER AND THE IMPORTANCE OF THE EPIGENOME IN DIAGNOSING AND PREVENTING THIS DEVASTATING DISEASE. 2007 4 6199 41 THE IMPORTANCE OF EPIGENETICS IN THE DEVELOPMENT OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE. IT IS GENERALLY ACCEPTED THAT GENETIC PREDISPOSITION PLAYS A ROLE IN COPD DEVELOPMENT IN SUSCEPTIBLE INDIVIDUALS. THEREFORE, MANY CANDIDATE GENES THAT COULD BE LINKED TO THE DEVELOPMENT OF DISEASE HAVE BEEN EXAMINED IN COPD. HOWEVER, INCONSISTENT RESULTS IN DIFFERENT STUDY POPULATIONS OFTEN LIMIT THIS APPROACH, SUGGESTING THAT NOT ONLY GENETICS, BUT ALSO OTHER FACTORS, MAY BE CONTRIBUTED TO THE SUSCEPTIBILITY TO COPD. EPIGENETIC MECHANISMS CAN AFFECT THE TRANSCRIPTIONAL ACTIVITY OF SPECIFIC GENES, AT DIFFERENT POINTS IN TIME, AND IN DIFFERENT ORGANS. MOREOVER, THESE MECHANISMS CAN HAVE AN EFFECT ON PEOPLE'S HEALTH. RECENTLY, THERE IS EMERGING EVIDENCE SUPPORTING A ROLE OF EPIGENETICS FOR THE REGULATION OF INFLAMMATORY GENES IN DISEASES SUCH AS ASTHMA AND COPD. MOREOVER, RECENT STUDIES SUGGEST THAT THE CURRENTLY USED TREATMENTS INCLUDING CORTICOSTEROIDS MAY WORK THROUGH EPIGENETIC MECHANISMS. EPIGENETIC REGULATION CAN BE REPROGRAMMED, POTENTIALLY AFFECTING THE RISK, AETIOLOGY AND TREATMENT OF VARIOUS DISEASE STATES. THE EPIGENETICALLY INFLUENCED PHENOTYPE COULD BE REVERSED WITH DEMETHYLATING OR DEACETYLATING AGENTS, CONSISTENT WITH EPIGENETIC PLASTICITY. THE POSTNATAL REVERSIBILITY OF THESE METHYLATION OR ACETYLATION EVENTS MAY THEREFORE PROVIDE GOOD OPPORTUNITIES FOR INTERVENTION. THE RECOGNITION OF THE ROLE OF GENETIC AND EPIGENETIC MECHANISMS IN THE DEVELOPMENT OF COPD MAY IDENTIFY NOVEL TARGETS THAT HATCH NEW THERAPIES FOR PATIENTS WITH COPD. 2011 5 551 54 AUTOIMMUNITY AS AN ETIOLOGICAL FACTOR OF CANCER: THE TRANSFORMATIVE POTENTIAL OF CHRONIC TYPE 2 INFLAMMATION. RECENT EPIDEMIOLOGICAL STUDIES HAVE FOUND AN ALARMING TREND OF INCREASED CANCER INCIDENCE IN ADULTS YOUNGER THAN 50 YEARS OF AGE AND PROJECTED A SUBSTANTIAL RISE IN CANCER INCIDENCE OVER THE NEXT 10 YEARS IN THIS AGE GROUP. THIS TREND WAS EXEMPLIFIED IN THE INCIDENCE OF NON-CARDIA GASTRIC CANCER AND ITS DISPROPORTIONATE IMPACT ON NON-HISPANIC WHITE FEMALES UNDER THE AGE OF 50. THE TREND IS CONCURRENT WITH THE INCREASING INCIDENCE OF AUTOIMMUNE DISEASES IN INDUSTRIALIZED COUNTRIES, SUGGESTING A CAUSAL LINK BETWEEN THE TWO. WHILE AUTOIMMUNITY HAS BEEN SUSPECTED TO BE A RISK FACTOR FOR SOME CANCERS, THE EXACT MECHANISMS UNDERLYING THE CONNECTION BETWEEN AUTOIMMUNITY AND CANCER REMAIN UNCLEAR AND ARE OFTEN CONTROVERSIAL. THE LINK HAS BEEN ATTRIBUTED TO SEVERAL MEDIATORS SUCH AS IMMUNE SUPPRESSION, INFECTION, DIET, ENVIRONMENT, OR, PERHAPS MOST PLAUSIBLY, CHRONIC INFLAMMATION BECAUSE OF ITS WELL-RECOGNIZED ROLE IN TUMORIGENESIS. IN THAT REGARD, AUTOIMMUNE CONDITIONS ARE COMMON CAUSES OF CHRONIC INFLAMMATION AND MAY TRIGGER REPETITIVE CYCLES OF ANTIGEN-SPECIFIC CELL DAMAGE, TISSUE REGENERATION, AND WOUND HEALING. ILLUSTRATING THE CONNECTION BETWEEN AUTOIMMUNE DISEASES AND CANCER ARE PATIENTS WHO HAVE AN INCREASED RISK OF CANCER DEVELOPMENT ASSOCIATED WITH GENETICALLY PREDISPOSED INSUFFICIENCY OF CYTOTOXIC T LYMPHOCYTE-ASSOCIATED PROTEIN 4 (CTLA4), A PROTOTYPICAL IMMUNE CHECKPOINT AGAINST AUTOIMMUNITY AND ONE OF THE MAIN TARGETS OF CANCER IMMUNE THERAPY. THE TUMORIGENIC PROCESS TRIGGERED BY CTLA4 INSUFFICIENCY HAS BEEN SHOWN IN A MOUSE MODEL TO BE DEPENDENT ON THE TYPE 2 CYTOKINES INTERLEUKIN-4 (IL4) AND INTERLEUKIN-13 (IL13). IN THIS TYPE 2 INFLAMMATORY MILIEU, CROSSTALK WITH TYPE 2 IMMUNE CELLS MAY INITIATE EPIGENETIC REPROGRAMMING OF EPITHELIAL CELLS, LEADING TO A METAPLASTIC DIFFERENTIATION AND EVENTUALLY MALIGNANT TRANSFORMATION EVEN IN THE ABSENCE OF CLASSICAL ONCOGENIC MUTATIONS. THOSE FINDINGS COMPLEMENT A LARGE BODY OF EVIDENCE FOR TYPE 1, TYPE 3, OR OTHER INFLAMMATORY MEDIATORS IN INFLAMMATORY TUMORIGENESIS. THIS REVIEW ADDRESSES THE POTENTIAL OF AUTOIMMUNITY AS A CAUSAL FACTOR FOR TUMORIGENESIS, THE UNDERLYING INFLAMMATORY MECHANISMS THAT MAY VARY DEPENDING ON HOST-ENVIRONMENT VARIATIONS, AND IMPLICATIONS TO CANCER PREVENTION AND IMMUNOTHERAPY. 2021 6 2507 36 EPIGENETICS AND OBESITY: THE DEVIL IS IN THE DETAILS. OBESITY IS A COMPLEX DISEASE WITH MULTIPLE WELL-DEFINED RISK FACTORS. NEVERTHELESS, SUSCEPTIBILITY TO OBESITY AND ITS SEQUELAE WITHIN OBESOGENIC ENVIRONMENTS VARIES GREATLY FROM ONE PERSON TO THE NEXT, SUGGESTING A ROLE FOR GENE X ENVIRONMENT INTERACTIONS IN THE ETIOLOGY OF THE DISORDER. EPIGENETIC REGULATION OF THE HUMAN GENOME PROVIDES A PUTATIVE MECHANISM BY WHICH SPECIFIC ENVIRONMENTAL EXPOSURES CONVEY RISK FOR OBESITY AND OTHER HUMAN DISEASES AND IS ONE POSSIBLE MECHANISM THAT UNDERLIES THE GENE X ENVIRONMENT/TREATMENT INTERACTIONS OBSERVED IN EPIDEMIOLOGICAL STUDIES AND CLINICAL TRIALS. A STUDY PUBLISHED IN BMC MEDICINE THIS MONTH BY WANG ET AL. REPORTS ON AN EXAMINATION OF DNA METHYLATION IN PERIPHERAL BLOOD LEUKOCYTES OF LEAN AND OBESE ADOLESCENTS, COMPARING METHYLATION PATTERNS BETWEEN THE TWO GROUPS. THE AUTHORS IDENTIFIED TWO GENES THAT WERE DIFFERENTIALLY METHYLATED, BOTH OF WHICH HAVE ROLES IN IMMUNE FUNCTION. HERE WE OVERVIEW THE FINDINGS FROM THIS STUDY IN THE CONTEXT OF THOSE EMERGING FROM OTHER RECENT GENETIC AND EPIGENETIC STUDIES, DISCUSS THE STRENGTHS AND WEAKNESSES OF THE STUDY AND SPECULATE ON THE FUTURE OF EPIGENETICS IN CHRONIC DISEASE RESEARCH. 2010 7 1010 35 CHRONICALLY ELEVATED PROLIFERATION AS A RISK FACTOR FOR NEOPLASIA. CHRONIC DISEASE CONDITIONS THAT ARE ASSOCIATED WITH ELEVATED PROLIFERATION ARE WELL ESTABLISHED AS RISK FACTORS FOR CANCER DEVELOPMENT. THESE MAY BE DUE TO VIRUSES (FOR EXAMPLE, IN THE CASE OF HEPATITIS AND LIVER CANCER), BACTERIAL INFECTIONS, PARASITE INFESTATION OR PHYSICAL TRAUMA. IN ADDITION TO THESE EXOGENOUS AGENTS THERE ARE ALSO METABOLIC ABNORMALITIES THAT CAN CONTRIBUTE, CAUSED BY GENETIC OR EPIGENETIC INFLUENCE. IN THE LATTER CASE, AN INCREASE IN SERUM LEVELS OF THE HORMONES OESTROGEN, TESTOSTERONE AND INSULIN MAY BE OF SPECIAL IMPORTANCE. THE PRESENT REVIEW CONCENTRATES ATTENTION ON FACTORS THAT INDUCE ELEVATED CELL TURNOVER AND FOR WHICH THERE IS EPIDEMIOLOGICAL AND/OR EXPERIMENTAL EVIDENCE OF A LINK WITH NEOPLASIA, WITH PARTICULAR STRESS ON THE INDIVIDUAL ORGAN OR TISSUE LEVEL. 1998 8 1958 39 EPIGENETIC AGING AND COLORECTAL CANCER: STATE OF THE ART AND PERSPECTIVES FOR FUTURE RESEARCH. ALTHOUGH TRANSLATIONAL RESEARCH HAS IDENTIFIED A LARGE NUMBER OF POTENTIAL BIOMARKERS INVOLVED IN COLORECTAL CANCER (CRC) CARCINOGENESIS, A BETTER UNDERSTANDING OF THE MOLECULAR PATHWAYS ASSOCIATED WITH BIOLOGICAL AGING IN COLORECTAL CELLS AND TISSUES IS NEEDED. HERE, WE AIM TO SUMMARIZE THE STATE OF THE ART ABOUT THE ROLE OF AGE ACCELERATION, DEFINED AS THE DIFFERENCE BETWEEN EPIGENETIC AGE AND CHRONOLOGICAL AGE, IN THE DEVELOPMENT AND PROGRESSION OF CRC. SOME STUDIES HAVE SHOWN THAT ACCELERATED BIOLOGICAL AGING IS POSITIVELY ASSOCIATED WITH THE RISK OF CANCER AND DEATH IN GENERAL. IN LINE WITH THESE FINDINGS, OTHER STUDIES HAVE SHOWN HOW THE ASSESSMENT OF EPIGENETIC AGE IN PEOPLE AT RISK FOR CRC COULD BE HELPFUL FOR MONITORING THE MOLECULAR RESPONSE TO PREVENTIVE INTERVENTIONS. MOREOVER, IT WOULD BE INTERESTING TO INVESTIGATE WHETHER ABERRANT EPIGENETIC AGING COULD HELP IDENTIFY CRC PATIENTS WITH A HIGH RISK OF RECURRENCE AND A WORST PROGNOSIS, AS WELL AS THOSE WHO RESPOND POORLY TO TREATMENT. YET, THE APPLICATION OF THIS NOVEL CONCEPT IS STILL IN ITS INFANCY, AND FURTHER RESEARCH SHOULD BE ENCOURAGED IN ANTICIPATION OF FUTURE APPLICATIONS IN CLINICAL PRACTICE. 2020 9 6771 34 [ACQUIRED DISORDERS AND EPIGENETICS]. EPIGENETIC MODIFICATIONS, INVOLVING DNA METHYLATION AND HISTONE MODIFICATIONS, ARE MAINTAINED UPON SOMATIC CELL REPLICATION, AND ARE FUNDAMENTAL MECHANISMS FOR CELLULAR MEMORY. DNA METHYLATION OF PROMOTER CPG ISLANDS OF TUMOR-SUPPRESSOR GENES CAN SILENCE THEIR DOWNSTREAM GENES, AND CAN BE CAUSALLY INVOLVED IN CANCER DEVELOPMENT AND PROGRESSION. SINCE THIS EFFECT IS THE SAME WITH THAT OF INACTIVATING MUTATIONS, THE NATURES OF DNA METHYLATION WERE ONCE CONSIDERED TO BE SIMILAR TO MUTATIONS. HOWEVER, RECENTLY, IT WAS REVEALED THAT A LARGE NUMBER OF EPIGENETIC ALTERATIONS ARE PRESENT IN A SINGLE CANCER CELL, THAT A LARGE NUMBER OF CELLS HAVE AN EPIGENETIC ALTERATION OF A SPECIFIC GENE IN NON-CANCEROUS, THUS POLYCLONAL, TISSUES, THAT GENE SPECIFICITY IN METHYLATION INDUCTION IS PRESENT ACCORDING TO TISSUE TYPES AND INDUCERS, AND THAT CHRONIC INFLAMMATION IS DEEPLY INVOLVED IN METHYLATION INDUCTION. THESE FACTS SUGGEST THAT EPIGENETIC ALTERATIONS OF KEY GENES INVOLVED IN ACQUIRED CHRONIC DISORDERS CAN BE PRESENT IN A SIGNIFICANT FRACTION OF CELLS IN A TISSUE, AND THUS CAN IMPAIR THE FUNCTION OF THE TISSUE. ASSOCIATIONS BETWEEN EPIGENETIC ALTERATIONS AND BEHAVIOR, MEMORY, MENTAL DISORDERS, NEUROLOGICAL DISORDERS, METABOLIC DISORDERS, ALLERGY, AUTOIMMUNE DISORDERS, AND OTHER DISORDERS HAVE BEEN REPORTED. FURTHER RESEARCH IN THE FIELD IS NECESSARY TO CLARIFY THE CAUSAL ROLES OF THESE EPIGENETIC ALTERATIONS IN DISEASE DEVELOPMENT, AND TO APPLY THE FINDINGS TO NEW STRATEGIES OF DISEASE PREVENTION, DIAGNOSIS, AND TREATMENT. 2010 10 5373 47 RECENT ADVANCES IN UNDERSTANDING THE ROLE OF DIET AND OBESITY IN THE DEVELOPMENT OF COLORECTAL CANCER. COLORECTAL CANCER (CRC) IS A MAJOR CAUSE OF PREMATURE DEATH IN THE UK AND MANY DEVELOPED COUNTRIES. HOWEVER, THE RISK OF DEVELOPING CRC IS WELL RECOGNISED TO BE ASSOCIATED NOT ONLY WITH DIET BUT ALSO WITH OBESITY AND LACK OF EXERCISE. WHILE EPIDEMIOLOGICAL EVIDENCE SHOWS AN ASSOCIATION WITH FACTORS SUCH AS HIGH RED MEAT INTAKE AND LOW INTAKE OF VEGETABLES, FIBRE AND FISH, THE MECHANISMS UNDERLYING THESE EFFECTS ARE ONLY NOW BEING ELUCIDATED. CRC DEVELOPS OVER MANY YEARS AND IS TYPICALLY CHARACTERISED BY AN ACCUMULATION OF MUTATIONS, WHICH MAY ARISE AS A CONSEQUENCE OF INHERITED POLYMORPHISMS IN KEY GENES, BUT MORE COMMONLY AS A RESULT OF SPONTANEOUSLY ARISING MUTATIONS AFFECTING GENES CONTROLLING CELL PROLIFERATION, DIFFERENTIATION, APOPTOSIS AND DNA REPAIR. EPIGENETIC CHANGES ARE OBSERVED THROUGHOUT THE PROGRESS FROM NORMAL MORPHOLOGY THROUGH FORMATION OF ADENOMA, AND THE SUBSEQUENT DEVELOPMENT OF CARCINOMA. THE REASONS WHY THIS ACCUMULATION OF LOSS OF HOMOEOSTATIC CONTROLS ARISES ARE UNCLEAR BUT CHRONIC INFLAMMATION HAS BEEN PROPOSED TO PLAY A CENTRAL ROLE. OBESITY IS ASSOCIATED WITH INCREASED PLASMA LEVELS OF CHEMOKINES AND ADIPOKINES CHARACTERISTIC OF CHRONIC SYSTEMIC INFLAMMATION, AND DIETARY FACTORS SUCH AS FISH OILS AND PHYTOCHEMICALS HAVE BEEN SHOWN TO HAVE ANTI-INFLAMMATORY PROPERTIES AS WELL AS MODULATING ESTABLISHED RISK FACTORS SUCH AS APOPTOSIS AND CELL PROLIFERATION. THERE IS ALSO SOME EVIDENCE THAT DIET CAN MODIFY EPIGENETIC CHANGES. THIS PAPER BRIEFLY REVIEWS THE CURRENT STATE OF KNOWLEDGE IN RELATION TO CRC DEVELOPMENT AND CONSIDERS EVIDENCE FOR POTENTIAL MECHANISMS BY WHICH DIET MAY MODIFY RISK. 2011 11 396 42 AN UPDATE ON EPIGENETICS AND CHILDHOOD RESPIRATORY DISEASES. EPIGENETIC MECHANISMS, DEFINED AS CHANGES IN PHENOTYPE OR GENE EXPRESSION CAUSED BY MECHANISMS OTHER THAN CHANGES IN THE UNDERLYING DNA SEQUENCE, HAVE BEEN PROPOSED TO CONSTITUTE A LINK BETWEEN GENETIC AND ENVIRONMENTAL FACTORS THAT AFFECT COMPLEX DISEASES. RECENT STUDIES SHOW THAT DNA METHYLATION, ONE OF THE KEY EPIGENETIC MECHANISMS, IS ALTERED IN CHILDREN EXPOSED TO AIR POLLUTANTS AND ENVIRONMENTAL TOBACCO SMOKE EARLY IN LIFE. SEVERAL CANDIDATE GENE STUDIES ON EPIGENETICS HAVE BEEN PUBLISHED TO DATE, BUT IT IS ONLY RECENTLY THAT GLOBAL METHYLATION ANALYSES HAVE BEEN PERFORMED FOR RESPIRATORY DISORDERS SUCH AS ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE. HOWEVER, LARGE-SCALE STUDIES WITH ADEQUATE POWER ARE YET TO BE PRESENTED IN CHILDREN, AND IMPLICATIONS FOR CLINICAL USE REMAIN TO BE EVALUATED. IN THIS REVIEW, WE SUMMARIZE THE RECENT ADVANCES IN EPIGENETICS AND RESPIRATORY DISORDERS IN CHILDREN, WITH A MAIN FOCUS ON METHODOLOGICAL CHALLENGES AND ANALYSES RELATED TO PHENOTYPE AND EXPOSURE USING GLOBAL METHYLATION APPROACHES. 2014 12 5119 38 POSSIBLE CONTRIBUTION OF CHRONIC INFLAMMATION IN THE INDUCTION OF CANCER IN RHEUMATIC DISEASES. SEVERAL CHRONIC INFLAMMATORY CONDITIONS AND AUTOIMMUNE DISEASES INVOLVING DIFFERENT ORGANS AND TISSUES HAVE BEEN FOUND AT RISK OF PROGRESSION TO CANCER. A WIDE ARRAY OF PROINFLAMMATORY CYTOKINES, PROSTAGLANDINS, NITRIC OXIDE PRODUCTS, AND MATRICELLULAR PROTEINS ARE CLOSELY INVOLVED IN PREMALIGNANT AND MALIGNANT TRANSITION OF CELLS ALMOST ALWAYS IN A BACKGROUND OF CHRONIC INFLAMMATION. INTERESTINGLY, EPIGENETIC PERTURBATIONS (I.E. MIRNA ABERRATIONS, ALTERED DNA METHYLATION) TOGETHER WITH IMPORTANT STEROID HORMONE METABOLIC CHANGES (I.E. OESTROGENS), OR THE ALTERED VITAMIN D CONCENTRATIONS THAT MAY UNBALANCE THE IMMUNE / INFLAMMATORY RESPONSE, HAVE BEEN FOUND LINKED TO THE RISK AND SEVERITY IN SEVERAL CHRONIC INFLAMMATORY CONDITIONS, AS WELL AS IN CANCER. IN PARTICULAR, IT IS EVIDENT, THAT NOT ONLY THE PARENT OESTROGEN BUT ALSO OESTROGEN METABOLITES SHOULD BE TAKEN INTO ACCOUNT WHEN THIS PROCESS IS EVALUATED, SPECIALLY THE FORMATION OF CATECHOLOESTROGEN METABOLITES, THAT ARE CAPABLE OF FORMING EITHER STABLE OR DEPURINATING DNA ADDUCTS, WHICH CAN CAUSE EXTENSIVE DNA DAMAGE. IT IS INTERESTING THAT TODAY THE SUCCESSFUL TREATMENT OF SEVERAL CHRONIC IMMUNE/INFLAMMATORY RHEUMATIC DISEASES IS OBTAINED ALSO BY USING MEDICATIONS INITIALLY DEVELOPED FOR THEIR USE IN ONCOLOGY. THE CIRCADIAN INCREASE OF GROWTH FACTORS, SPECIALLY DURING THE LATE NIGHT, IN BOTH CHRONIC INFLAMMATION AND IN CANCER PATIENTS, AS WELL AS THE PRESENCE OF OESTROGEN-REGULATED CIRCADIAN MECHANISMS, SUGGESTS FURTHER IMPORTANT LINKS. 2014 13 6812 39 [EPIGENETICS, INTERFACE BETWEEN ENVIRONMENT AND GENES: ROLE IN COMPLEX DISEASES]. EPIGENETICS IS THE STUDY OF HERITABLE CHANGES IN GENE EXPRESSION OR CELLULAR PHENOTYPE CAUSED BY MECHANISMS OTHER THAN CHANGES IN THE UNDERLYING DNA SEQUENCE. EPIGENETICS IS ONE OF THE MAJOR MECHANISMS EXPLAINING THE "DEVELOPMENTAL ORIGIN OF HEALTH AND DISEASES" (DOHAD). BESIDES GENETIC BACKGROUND INHERITED FROM PARENTS, WHICH CONFERS SUSCEPTIBILITY TO CERTAIN PATHOLOGIES, EPIGENETIC CHANGES CONSTITUTE THE MEMORY OF PREVIOUS EVENTS, EITHER POSITIVE OR NEGATIVE, ALONG THE LIFE CYCLE, INCLUDING AT THE IN UTERO STAGE. THE LATER EXPOSITION TO HOSTILE ENVIRONMENT MAY REVEAL SUCH SUSCEPTIBILITY, WITH THE DEVELOPMENT OF VARIOUS PATHOLOGIES, AMONG THEM NUMEROUS CHRONIC COMPLEX DISEASES. THE DEMONSTRATION OF SUCH A SEQUENCE OF EVENTS HAS BEEN SHOWN FOR METABOLIC DISEASES AS OBESITY, METABOLIC SYNDROME AND TYPE 2 DIABETES, CARDIOVASCULAR DISEASE AND CANCER. IN CONTRAST TO GENETIC PREDISPOSITION, WHICH IS IRREVERSIBLE, EPIGENETIC CHANGES ARE POTENTIALLY REVERSIBLE, THUS GIVING TARGETS NOT ONLY FOR PREVENTION, BUT POSSIBLY ALSO FOR THE TREATMENT OF CERTAIN COMPLEX DISEASES. 2012 14 2017 43 EPIGENETIC BIOMARKERS IN RHEUMATOLOGY - THE FUTURE? EPIGENETIC CHANGES ARE STABLE MODIFICATIONS OF DNA OR HISTONES THAT PROFOUNDLY ALTER GENE EXPRESSION. THEY CAN BE CHANGED BY ENVIRONMENTAL INFLUENCES AND CAN THEN BE PASSED ON TO DAUGHTER CELLS OR VIA THE GERM LINE TO OFFSPRING. A VARIETY OF CHANGES IN EPIGENETIC MARKS AND IN THE EXPRESSION OF NONCODING RNA HAS BEEN FOUND IN CANCER AS WELL AS IN CHRONIC INFLAMMATORY DISEASES. INTERESTINGLY, IN BOTH DISEASES SIMILAR MECHANISMS AND PATHWAYS ARE AFFECTED ALBEIT OFTEN TO A DIFFERENT EXTENT. DNA METHYLATION IS OFTEN LOST IN REPETITIVE SEQUENCES, WHILE IN PROMOTER REGIONS HYPO- AS WELL AS HYPERMETHYLATION IS FOUND. CHANGES IN MICRORNA LEVELS TYPICALLY AFFECT MICRORNAS THAT ARE CHANGED BY AN INFLAMMATORY ENVIRONMENT, BUT DISEASE SPECIFIC CHANGES HAVE ALSO BEEN FOUND IN THE BLOOD AND VARIOUS CELL TYPES OF PATIENTS WITH RHEUMATOID ARTHRITIS, SYSTEMIC LUPUS ERYTHEMATOSUS AND OTHER RHEUMATIC DISEASES. THEREFORE, CHANGES IN THE EXPRESSION OF MICRORNA IN PARTICULAR, BUT ALSO DEMETHYLATED GENE LOCI, HAVE BEEN PROPOSED AS POTENTIAL BIOMARKERS IN CHRONIC INFLAMMATORY DISEASES AND IN CANCER. POTENTIALLY, THESE CHANGES COULD BE USED FOR EARLY DIAGNOSIS AND ALSO TO PREDICT TREATMENT RESPONSE. UNFORTUNATELY MOST STUDIES IN RHEUMATOLOGY UP TO NOW WERE NOT DESIGNED TO VALIDATE THESE EPIGENETIC CHANGES AS BIOMARKERS. SINCE THE CANCER FIELD IS MUCH MORE ADVANCED IN THE USAGE OF BIOMARKERS FOR DISEASE SUBCLASSIFICATIONS AND SUBSEQUENT THERAPEUTIC DECISIONS, IT IS WORTHWHILE TO TAKE A CLOSER LOOK AT THE BIOMARKERS, METHODS AND PROCEDURES USED IN ONCOLOGY AND TO SEE WHICH OF THESE COULD ALSO BE APPLIED TO PREDICTING DISEASE SEVERITY AND THERAPEUTIC RESPONSE IN RHEUMATIC DISEASES. THIS ARTICLE WILL HIGHLIGHT COMMON EPIGENETIC PATHWAYS ACTIVATED IN CANCER AND VARIOUS RHEUMATIC DISEASES AND SUMMARISE EPIGENETIC CHANGES THAT HAVE THE POTENTIAL TO BECOME BIOMARKERS IN RHEUMATIC DISEASES. 2016 15 5618 31 SARS-COV-2 INTERACTION WITH HUMAN DNA METHYL TRANSFERASE 1: A POTENTIAL RISK FOR INCREASING THE INCIDENCE OF LATER CHRONIC DISEASES IN THE SURVIVED PATIENTS. CURRENTLY, THE COVID-19 PANDEMIC IS THE MOST DISCUSSED SUBJECT IN MEDICAL RESEARCHES WORLDWIDE. AS THE KNOWLEDGE IS EXPANDED ABOUT THE DISEASE, MORE HYPOTHESES BECOME CREATED. A RECENT STUDY ON THE VIRAL PROTEIN INTERACTION MAP REVEALED THAT SARS-COV-2 OPEN READING FRAME 8 (ORF8) INTERACTS WITH HUMAN DNA METHYL TRANSFERASE1 (DNMT1), AN ACTIVE EPIGENETIC AGENT IN DNA METHYLATION. MOREOVER, DNMT1 IS A CONTRIBUTOR TO A VARIETY OF CHRONIC DISEASES WHICH COULD CAUSE SOME EPIGENETIC DYSREGULATION IN INFECTED CELLS, ESPECIALLY LEUKOCYTES, PANCREATIC BETA, AND ENDOTHELIAL CELLS. REGARDING THE FACT THAT EPIGENETIC ALTERATIONS HAVE A PARTIAL, BUT NOT COMPLETELY REVERSIBLE PHENOMENA, IT RAISES THE QUESTION THAT IF THIS INTERACTION MAY CAUSE LONG-TERM COMPLICATIONS SUCH AS DIABETES, ATHEROSCLEROSIS, CANCER, AND AUTOIMMUNE DISEASES. ACCORDINGLY, LONG FOLLOW-UP STUDIES ON THE RECOVERED PATIENTS FROM COVID-19 ARE RECOMMENDED. 2022 16 186 41 ACCUMULATION OF GENETIC AND EPIGENETIC ALTERATIONS IN NORMAL CELLS AND CANCER RISK. CANCERS DEVELOP DUE TO THE ACCUMULATION OF GENETIC AND EPIGENETIC ALTERATIONS. GENETIC ALTERATIONS ARE INDUCED BY AGING, MUTAGENIC CHEMICALS, ULTRAVIOLET LIGHT, AND OTHER FACTORS; WHEREAS, EPIGENETIC ALTERATIONS ARE MAINLY BY AGING AND CHRONIC INFLAMMATION. THE ACCUMULATION AND PATTERNS OF ALTERATIONS IN NORMAL CELLS REFLECT OUR PAST EXPOSURE LEVELS AND LIFE HISTORY. MOST ACCUMULATED ALTERATIONS ARE CONSIDERED AS PASSENGERS, BUT THEIR ACCUMULATION IS CORRELATED WITH CANCER DRIVERS. THIS HAS BEEN SHOWN FOR ABERRANT DNA METHYLATION BUT HAS ONLY BEEN SPECULATED FOR GENETIC ALTERATIONS. HOWEVER, RECENT TECHNOLOGICAL ADVANCEMENTS HAVE ENABLED MEASUREMENT OF RARE POINT MUTATIONS, AND STUDIES HAVE SHOWN THAT THEIR ACCUMULATION LEVELS ARE INDEED CORRELATED WITH CANCER RISK. WHEN THE ACCUMULATION LEVELS OF ABERRANT DNA METHYLATION AND POINT MUTATIONS ARE COMBINED, RISK PREDICTION BECOMES EVEN MORE ACCURATE. WHEN HIGH LEVELS OF ALTERATIONS ACCUMULATE, THE TISSUE HAS A HIGH RISK OF DEVELOPING CANCER OR EVEN MULTIPLE CANCERS AND IS CONSIDERED AS A "CANCERIZATION FIELD", WITH OR WITHOUT EXPANSION OF PHYSIOLOGICAL PATCHES OF CLONAL CELLS. IN THIS REVIEW, WE DESCRIBE THE FORMATION OF A CANCERIZATION FIELD AND HOW WE CAN APPLY ITS DETECTION IN PRECISION CANCER RISK DIAGNOSIS. 2019 17 5742 29 SMOKING MOLECULAR DAMAGE IN BRONCHIAL EPITHELIUM. OUR UNDERSTANDING OF THE MOLECULAR PATHOLOGY OF LUNG CANCER IS ADVANCING RAPIDLY WITH SEVERAL SPECIFIC GENES AND CHROMOSOMAL REGIONS BEING IDENTIFIED. LUNG CANCER APPEARS TO REQUIRE MANY MUTATIONS IN BOTH DOMINANT AND RECESSIVE ONCOGENES TO POSSESS MALIGNANT PHENOTYPES. SEVERAL GENETIC AND EPIGENETIC CHANGES ARE COMMON TO ALL LUNG CANCER HISTOLOGIC TYPES, WHILE OTHERS APPEAR TO BE CELL TYPE SPECIFIC. HOWEVER, SPECIFIC ROLES OF THE GENES UNDERGOING MUTATIONS AND THE ORDER OF CUMULATIVE MOLECULAR CHANGES THAT LEAD TO THE DEVELOPMENT OF EACH LUNG TUMOR HISTOLOGIC TYPE REMAIN TO BE FULLY ELUCIDATED. RECENT FINDINGS OF MOLECULAR ABNORMALITIES IN NORMAL APPEARING AND PRENEOPLASTIC BRONCHIAL EPITHELIUM FROM PATIENTS WITH LUNG CANCER AND CHRONIC SMOKERS SUGGEST THAT GENETIC CHANGES MAY SERVE AS BIOMARKERS FOR EARLY DIAGNOSIS, RISK ASSESSMENT AND MONITORING RESPONSE TO CHEMOPREVENTION. 2002 18 2523 45 EPIGENETICS AND THE TRANSITION FROM ACUTE TO CHRONIC PAIN. OBJECTIVE: THE OBJECTIVE OF THIS STUDY WAS TO REVIEW THE EPIGENETIC MODIFICATIONS INVOLVED IN THE TRANSITION FROM ACUTE TO CHRONIC PAIN AND TO IDENTIFY POTENTIAL TARGETS FOR THE DEVELOPMENT OF NOVEL, INDIVIDUALIZED PAIN THERAPEUTICS. BACKGROUND: EPIGENETICS IS THE STUDY OF HERITABLE MODIFICATIONS IN GENE EXPRESSION AND PHENOTYPE THAT DO NOT REQUIRE A CHANGE IN GENETIC SEQUENCE TO MANIFEST THEIR EFFECTS. ENVIRONMENTAL TOXINS, MEDICATIONS, DIET, AND PSYCHOLOGICAL STRESSES CAN ALTER EPIGENETIC PROCESSES SUCH AS DNA METHYLATION, HISTONE ACETYLATION, AND RNA INTERFERENCE. AS EPIGENETIC MODIFICATIONS POTENTIALLY PLAY AN IMPORTANT ROLE IN INFLAMMATORY CYTOKINE METABOLISM, STEROID RESPONSIVENESS, AND OPIOID SENSITIVITY, THEY ARE LIKELY KEY FACTORS IN THE DEVELOPMENT OF CHRONIC PAIN. ALTHOUGH OUR KNOWLEDGE OF THE HUMAN GENETIC CODE AND DISEASE-ASSOCIATED POLYMORPHISMS HAS GROWN SIGNIFICANTLY IN THE PAST DECADE, WE HAVE NOT YET BEEN ABLE TO ELUCIDATE THE MECHANISMS THAT LEAD TO THE DEVELOPMENT OF PERSISTENT PAIN AFTER NERVE INJURY OR SURGERY. DESIGN: THIS IS A FOCUSED LITERATURE REVIEW OF EPIGENETIC SCIENCE AND ITS RELATIONSHIP TO CHRONIC PAIN. RESULTS: SIGNIFICANT LABORATORY AND CLINICAL DATA SUPPORT THE NOTION THAT EPIGENETIC MODIFICATIONS ARE AFFECTED BY THE ENVIRONMENT AND LEAD TO DIFFERENTIAL GENE EXPRESSION. SIMILAR TO MECHANISMS INVOLVED IN THE DEVELOPMENT OF CANCER, NEURODEGENERATIVE DISEASE, AND INFLAMMATORY DISORDERS, THE LITERATURE ENDORSES AN IMPORTANT POTENTIAL ROLE FOR EPIGENETICS IN CHRONIC PAIN. CONCLUSIONS: EPIGENETIC ANALYSIS MAY IDENTIFY MECHANISMS CRITICAL TO THE DEVELOPMENT OF CHRONIC PAIN AFTER INJURY, AND MAY PROVIDE NEW PATHWAYS AND TARGET MECHANISMS FOR FUTURE DRUG DEVELOPMENT AND INDIVIDUALIZED MEDICINE. 2012 19 266 50 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 20 6288 44 THE POTENTIAL ROLE OF EPIGENETIC MODIFICATIONS ON DIFFERENT FACETS IN THE PERIODONTAL PATHOGENESIS. PERIODONTITIS IS A CHRONIC INFLAMMATORY DISEASE THAT AFFECTS THE SUPPORTING STRUCTURES OF TEETH. IN THE LITERATURE, THE ASSOCIATION BETWEEN THE PATHOGENICITY OF BACTERIA AND ENVIRONMENTAL FACTORS IN THIS REGARD HAVE BEEN EXTENSIVELY EXAMINED. IN THE PRESENT STUDY, WE WILL SHED LIGHT ON THE POTENTIAL ROLE THAT EPIGENETIC CHANGE CAN PLAY ON DIFFERENT FACETS OF ITS PROCESS, MORE PARTICULARLY THE MODIFICATIONS CONCERNING THE GENES INVOLVED IN INFLAMMATION, DEFENSE, AND IMMUNE SYSTEMS. SINCE THE 1960S, THE ROLE OF GENETIC VARIANTS IN THE ONSET AND SEVERITY OF PERIODONTAL DISEASE HAS BEEN WIDELY DEMONSTRATED. THESE MAKE SOME PEOPLE MORE SUSCEPTIBLE TO DEVELOPING IT THAN OTHERS. IT HAS BEEN DOCUMENTED THAT THE WIDE VARIATION IN ITS FREQUENCY FOR VARIOUS RACIAL AND ETHNIC POPULATIONS IS DUE PRIMARILY TO THE COMPLEX INTERPLAY AMONG GENETIC FACTORS WITH THOSE AFFECTING THE ENVIRONMENT AND THE DEMOGRAPHY. IN MOLECULAR BIOLOGY, EPIGENETIC MODIFICATIONS ARE DEFINED AS ANY CHANGE IN THE PROMOTER FOR THE CPG ISLANDS, IN THE STRUCTURE OF THE HISTONE PROTEIN, AS WELL AS POST-TRANSLATIONAL REGULATION BY MICRORNAS (MIRNAS), BEING KNOWN TO CONTRIBUTE TO THE ALTERATION IN GENE EXPRESSION FOR COMPLEX MULTIFACTORIAL DISEASES SUCH AS PERIODONTITIS. THE KEY ROLE OF EPIGENETIC MODIFICATION IS TO UNDERSTAND THE MECHANISM INVOLVED IN THE GENE-ENVIRONMENT INTERACTION, AND THE DEVELOPMENT OF PERIODONTITIS IS NOW THE SUBJECT OF MORE AND MORE STUDIES THAT ATTEMPT TO IDENTIFY WHICH FACTORS ARE STIMULATING IT, BUT ALSO AFFECT THE REDUCED RESPONSE TO THERAPY. 2023