1 1918 222 ENVIRONMENTAL CARCINOGENESIS AND TRANSGENERATIONAL TRANSMISSION OF CARCINOGENIC RISK: FROM GENETICS TO EPIGENETICS. THE DOMINANT PATHOGENIC MODEL, SOMATIC MUTATION THEORY (SMT), CONSIDERS CARCINOGENESIS AS A 'GENETIC ACCIDENT' DUE TO THE ACCUMULATION OF 'STOCHASTIC' DNA MUTATIONS. THIS MODEL WAS PROPOSED AND ACCEPTED BY THE SCIENTIFIC COMMUNITY WHEN CANCER MAINLY AFFECTED THE ELDERLY, BUT IT DOES NOT EXPLAIN THE EPIDEMIOLOGICAL OBSERVATION OF THE CONTINUOUS INCREASE IN CANCER INCIDENCE AMONG CHILDREN AND YOUNG ADULTS. SOMATIC MUTATION THEORY HAS BEEN PROPOSED FOR A REVISION BASED ON THE EMERGING EXPERIMENTAL EVIDENCE, AS IT DOES NOT FULLY ADDRESS SOME ISSUES THAT HAVE PROVEN TO BE CRUCIAL FOR CARCINOGENESIS, NAMELY: THE INFLAMMATORY CONTEXT OF CANCER; THE KEY ROLE PLAYED BY THE STROMA, MICROENVIRONMENT, ENDOTHELIAL CELLS, ACTIVATED MACROPHAGES, AND SURROUNDING TISSUES; AND THE DISTORTED DEVELOPMENTAL COURSE FOLLOWED BY THE NEOPLASTIC TISSUE. FURTHERMORE, SMT IS OFTEN NOT ABLE TO CONSIDER EITHER THE EXISTENCE OF SPECIFIC MUTATIONS RESULTING IN A WELL-DEFINED CANCER TYPE, OR A CLEAR RELATIONSHIP BETWEEN MUTATIONS AND TUMOR PROGRESSION. MOREOVER, IT DOES NOT EXPLAIN THE MECHANISM OF ACTION OF THE NON-MUTAGENIC AND ENVIRONMENTAL CARCINOGENS. IN THE LAST DECADE, CANCER RESEARCH HAS HIGHLIGHTED THE PROMINENT ROLE OF AN ALTERED REGULATION OF GENE EXPRESSION, SUGGESTING THAT CANCER SHOULD BE CONSIDERED AS A RESULT OF A POLYCLONAL EPIGENETIC DISRUPTION OF STEM/PROGENITOR CELLS, MEDIATED BY TUMOUR-INDUCING GENES. THE MATERNAL AND FETAL EXPOSURE TO A WIDE RANGE OF CHEMICALS AND ENVIRONMENTAL CONTAMINANTS IS RAISING THE ATTENTION OF THE SCIENTIFIC COMMUNITY. INDEED, THE MOST POWERFUL PROCARCINOGENIC MECHANISMS OF ENDOCRINE DISRUPTORS AND OTHER POLLUTANTS IS LINKED TO THEIR POTENTIAL TO INTERFERE EPIGENETICALLY WITH THE EMBRYO-FETAL PROGRAMMING OF TISSUES AND ORGANS, ALTERING THE REGULATION OF THE GENES INVOLVED IN THE CELL CYCLE, CELL PROLIFERATION, APOPTOSIS, AND OTHER KEY SIGNALING PATHWAYS. THE EMBRYO-FETAL EXPOSURE TO ENVIRONMENTAL, STRESSFUL, AND PROINFLAMMATORY TRIGGERS (FIRST HIT), SEEMS TO ACT AS A 'DISEASE PRIMER', MAKING FETAL CELLS AND TISSUES MORE SUSCEPTIBLE TO THE SUBSEQUENT ENVIRONMENTAL EXPOSURES (SECOND HIT), TRIGGERING THE CARCINOGENIC PATHWAYS. FURTHERMORE, EVEN AT THE MOLECULAR LEVEL, IN CARCINOGENESIS, 'EPIGENETICS PRECEDES GENETICS' AS GLOBAL DNA HYPOMETHYLATION, AND THE HYPERMETHYLATION OF TUMOR SUPPRESSOR GENES ARE COMMON BOTH IN CANCEROUS AND IN PRECANCEROUS CELLS, AND GENERALLY PRECEDE MUTATIONS. THESE EPIGENETIC MODELS MAY BETTER EXPLAIN THE INCREASE OF CANCER AND CHRONIC/DEGENERATIVE DISEASES IN THE LAST DECADES AND COULD BE USEFUL TO ADOPT APPROPRIATE PRIMARY PREVENTION MEASURES, ESSENTIALLY BASED ON THE REDUCTION OF MATERNAL-FETAL AND CHILD EXPOSURE TO SEVERAL PROCARCINOGENIC AGENTS AND FACTORS DISPERSED IN THE ENVIRONMENT AND IN THE FOOD-CHAINS, AS RECENTLY SUGGESTED BY THE WORLD HEALTH ORGANIZATION. 2018 2 6742 60 WHITHER THE ETIOPATHOGENESIS (AND SCOLIOGENY) OF ADOLESCENT IDIOPATHIC SCOLIOSIS? ALTHOUGH CONSIDERABLE PROGRESS HAD BEEN MADE IN THE PAST TWO DECADES IN UNDERSTANDING THE ETIOPATHOGENESIS OF ADOLESCENT IDIOPATHIC SCOLIOSIS (AIS), IT STILL LACKS AN AGREED THEORY OF ETIOPATHOGENESIS. ONE PROBLEM MAY BE THAT AIS RESULTS NOT FROM ONE CAUSE, BUT SEVERAL THAT INTERACT WITH VARIOUS GENETIC PREDISPOSING FACTORS. THERE IS A VIEW THERE ARE TWO OTHER PATHOGENIC PROCESSES FOR IDIOPATHIC SCOLIOSIS NAMELY, INITIATING (OR INDUCING), AND THOSE THAT CAUSE CURVE PROGRESSION. TWIN STUDIES AND OBSERVATIONS OF FAMILY AGGREGATION HAVE REVEALED SIGNIFICANT GENETIC CONTRIBUTIONS TO IDIOPATHIC SCOLIOSIS, THAT PLACE AIS AMONG OTHER COMMON DISEASE OR COMPLEX TRAITS WITH A HIGH HERITABILITY INTERPRETED BY THE GENETIC VARIANT HYPOTHESIS OF DISEASE. WE SUMMARIZE ETIOPATHOGENETIC KNOWLEDGE OF AIS AS THEORIES OF PATHOGENESIS INCLUDING RECENT MULTIPLE CONCEPTS, AND BLOOD TESTS FOR AIS BASED ON PREDICTIVE BIOMARKERS AND GENETIC VARIANTS THAT SIGNIFY DISEASE RISK. THERE IS INCREASING EVIDENCE FOR THE POSSIBILITY OF AN UNDERLYING NEUROLOGICAL DISORDER FOR AIS, RESEARCH WHICH HOLDS PROMISE. LIKE BRAIN RESEARCH, MOST AIS WORKERS FOCUS ON THEIR OWN CORNER AND THERE IS A NEED FOR GREATER INTEGRATION OF RESEARCH EFFORT. EPIGENETICS, A RELATIVELY RECENT FIELD, EVALUATES FACTORS CONCERNED WITH GENE EXPRESSION IN RELATION TO ENVIRONMENT, DISEASE, NORMAL DEVELOPMENT AND AGING, WITH A COMPLEX REGULATION ACROSS THE GENOME DURING THE FIRST DECADE OF LIFE. RESEARCH ON THE ROLE OF ENVIRONMENTAL FACTORS, EPIGENETICS AND CHRONIC NON-COMMUNICABLE DISEASES (NCDS) INCLUDING ADIPOSITY, AFTER A SLOW START, HAS EXPLODED IN THE LAST DECADE. NOT SO FOR AIS RESEARCH AND THE ENVIRONMENT WHERE, EXCEPT FOR MONOZYGOTIC TWIN STUDIES, THERE ARE ONLY SPORADIC REPORTS TO SUGGEST THAT ENVIRONMENTAL FACTORS ARE AT WORK IN ETIOLOGY. HERE, WE EXAMINE EPIGENETIC CONCEPTS AS THEY MAY RELATE TO HUMAN DEVELOPMENT, NORMAL LIFE HISTORY PHASES AND AIS PATHOGENESIS. ALTHOUGH AIS IS NOT REGARDED AS AN NCD, LIKE THEM, IT IS ASSOCIATED WITH WHOLE ORGANISM METABOLIC PHENOMENA, INCLUDING LOWER BODY MASS INDEX, LOWER CIRCULATING LEPTIN LEVELS AND OTHER SYSTEMIC DISORDERS. SOME EPIGENETIC RESEARCH APPLIED TO SILVER-RUSSELL SYNDROME AND ADIPOSITY IS EXAMINED, FROM WHICH SUGGESTIONS ARE MADE FOR CONSIDERATION OF AIS EPIGENETIC RESEARCH, CROSS-SECTIONAL AND LONGITUDINAL. THE WORD SCOLIOGENY IS SUGGESTED TO INCLUDE ETIOLOGY, PATHOGENESIS AND PATHOMECHANISM. 2012 3 6743 64 WHITHER THE ETIOPATHOGENESIS (AND SCOLIOGENY) OF ADOLESCENT IDIOPATHIC SCOLIOSIS? INCORPORATING PRESENTATIONS ON SCOLIOGENY AT THE 2012 IRSSD AND SRS MEETINGS. THIS PAPER AIMS TO INTEGRATE INTO CURRENT UNDERSTANDING OF AIS CAUSATION, ETIOPATHOGENETIC INFORMATION PRESENTED AT TWO MEETINGS DURING 2012 NAMELY, THE INTERNATIONAL RESEARCH SOCIETY OF SPINAL DEFORMITIES (IRSSD) AND THE SCOLIOSIS RESEARCH SOCIETY (SRS). THE ULTIMATE HOPE IS TO PREVENT THE OCCURRENCE OR PROGRESSION OF THE SPINAL DEFORMITY OF AIS WITH NON-INVASIVE TREATMENT, POSSIBLY MEDICAL. THIS MIGHT BE ATTAINED BY PERSONALISED POLYMECHANISTIC PREVENTIVE THERAPY TARGETING THE APPROPRIATE ETIOLOGY AND/OR ETIOPATHOGENETIC PATHWAYS, TO AVOID FUSION AND MAINTAIN SPINAL MOBILITY. ALTHOUGH CONSIDERABLE PROGRESS HAD BEEN MADE IN THE PAST TWO DECADES IN UNDERSTANDING THE ETIOPATHOGENESIS OF ADOLESCENT IDIOPATHIC SCOLIOSIS (AIS), IT STILL LACKS AN AGREED THEORY OF ETIOPATHOGENESIS. ONE PROBLEM MAY BE THAT AIS RESULTS NOT FROM ONE CAUSE, BUT SEVERAL THAT INTERACT WITH VARIOUS GENETIC PREDISPOSING FACTORS. THERE IS A VIEW THERE ARE TWO OTHER PATHOGENIC PROCESSES FOR IDIOPATHIC SCOLIOSIS NAMELY, INITIATING (OR INDUCING), AND THOSE THAT CAUSE CURVE PROGRESSION. TWIN STUDIES AND OBSERVATIONS OF FAMILY AGGREGATION HAVE REVEALED SIGNIFICANT GENETIC CONTRIBUTIONS TO IDIOPATHIC SCOLIOSIS, THAT PLACE AIS AMONG OTHER COMMON DISEASE OR COMPLEX TRAITS WITH A HIGH HERITABILITY INTERPRETED BY THE GENETIC VARIANT HYPOTHESIS OF DISEASE. WE SUMMARIZE ETIOPATHOGENETIC KNOWLEDGE OF AIS AS THEORIES OF PATHOGENESIS INCLUDING RECENT MULTIPLE CONCEPTS, AND BLOOD TESTS FOR AIS BASED ON PREDICTIVE BIOMARKERS AND GENETIC VARIANTS THAT SIGNIFY DISEASE RISK. THERE IS INCREASING EVIDENCE FOR THE POSSIBILITY OF AN UNDERLYING NEUROLOGICAL DISORDER FOR AIS, RESEARCH WHICH HOLDS PROMISE. LIKE BRAIN RESEARCH, MOST AIS WORKERS FOCUS ON THEIR OWN CORNER AND THERE IS A NEED FOR GREATER INTEGRATION OF RESEARCH EFFORT. EPIGENETICS, A RELATIVELY RECENT FIELD, EVALUATES FACTORS CONCERNED WITH GENE EXPRESSION IN RELATION TO ENVIRONMENT, DISEASE, NORMAL DEVELOPMENT AND AGING, WITH A COMPLEX REGULATION ACROSS THE GENOME DURING THE FIRST DECADE OF LIFE. RESEARCH ON THE ROLE OF ENVIRONMENTAL FACTORS, EPIGENETICS AND CHRONIC NON-COMMUNICABLE DISEASES (NCDS) INCLUDING ADIPOSITY, AFTER A SLOW START, HAS EXPLODED IN THE LAST DECADE. NOT SO FOR AIS RESEARCH AND THE ENVIRONMENT WHERE, EXCEPT FOR MONOZYGOTIC TWIN STUDIES, THERE ARE ONLY SPORADIC REPORTS TO SUGGEST THAT ENVIRONMENTAL FACTORS ARE AT WORK IN ETIOLOGY. HERE, WE EXAMINE EPIGENETIC CONCEPTS AS THEY MAY RELATE TO HUMAN DEVELOPMENT, NORMAL LIFE HISTORY PHASES AND AIS PATHOGENESIS. ALTHOUGH AIS IS NOT REGARDED AS AN NCD, LIKE THEM, IT IS ASSOCIATED WITH WHOLE ORGANISM METABOLIC PHENOMENA, INCLUDING LOWER BODY MASS INDEX, LOWER CIRCULATING LEPTIN LEVELS AND OTHER SYSTEMIC DISORDERS. SOME EPIGENETIC RESEARCH APPLIED TO SILVER-RUSSELL SYNDROME AND ADIPOSITY IS EXAMINED, FROM WHICH SUGGESTIONS ARE MADE FOR CONSIDERATION OF AIS EPIGENETIC RESEARCH, CROSS-SECTIONAL AND LONGITUDINAL. THE WORD SCOLIOGENY IS SUGGESTED TO INCLUDE ETIOLOGY, PATHOGENESIS AND PATHOMECHANISM. 2013 4 3837 38 IONIZING RADIATION-INDUCED OXIDATIVE STRESS, EPIGENETIC CHANGES AND GENOMIC INSTABILITY: THE PIVOTAL ROLE OF MITOCHONDRIA. PURPOSE: TO REVIEW THE DATA CONCERNING THE ROLE OF ENDOGENOUSLY GENERATED REACTIVE OXYGEN SPECIES (ROS) IN THE NON-TARGETED IONIZING RADIATION (IR) EFFECTS AND IN DETERMINATION OF THE CELL POPULATION'S FATE, BOTH EARLY AFTER EXPOSURE AND AFTER MANY GENERATIONS. CONCLUSIONS: THE SHORT-TERM AS WELL AS CHRONIC OXIDATIVE STRESS RESPONSES MAINLY ARE PRODUCED DUE TO ROS GENERATION BY THE ELECTRON TRANSPORT CHAIN (ETC) OF THE MITOCHONDRIA AND BY THE CYTOPLASMIC NADPH OXIDASES. WHETHER THE INDUCTION OF THE OXIDATIVE STRESS AND ITS CONSEQUENCES OCCUR OR ARE HAMPERED IN A SINGLE CELL LARGELY DEPENDS ON THE INTERACTION BETWEEN THE NUCLEUS AND THE CELLULAR POPULATION OF SEVERAL HUNDRED OR THOUSANDS OF MITOCHONDRIA THAT ARE GENETICALLY HETEROGENEOUS. HIGH INTRA-MITOCHONDRIAL ROS LEVEL IS DAMAGING THE MITOCHONDRIAL (MT) DNA AND ITS MUTATIONS AFFECT THE EPIGENETIC CONTROL MECHANISMS OF THE NUCLEAR (N) DNA, BY DECREASING THE ACTIVITY OF METHYLTRANSFERASES AND THUS, CAUSING GLOBAL DNA HYPOMETHYLATION. THESE CHANGES ARE TRANSMITTED TO THE PROGENY OF THE IRRADIATED CELLS. THE CHRONIC OXIDATIVE STRESS IS THE MAIN CAUSE OF THE LATE POST-RADIATION EFFECTS, INCLUDING CANCER, AND THIS MAKES IT AN IMPORTANT ADVERSE EFFECT OF EXPOSURE TO IR AND A TARGET FOR RADIOLOGICAL PROTECTION. 2015 5 5117 34 POSSIBLE ADVERSE EFFECTS OF HIGH-DOSE NICOTINAMIDE: MECHANISMS AND SAFETY ASSESSMENT. NICOTINAMIDE (NAM) AT DOSES FAR ABOVE THOSE RECOMMENDED FOR VITAMINS IS SUGGESTED TO BE EFFECTIVE AGAINST A WIDE SPECTRUM OF DISEASES AND CONDITIONS, INCLUDING NEUROLOGICAL DYSFUNCTIONS, DEPRESSION AND OTHER PSYCHOLOGICAL DISORDERS, AND INFLAMMATORY DISEASES. RECENT INCREASES IN PUBLIC AWARENESS ON POSSIBLE PRO-LONGEVITY EFFECTS OF NICOTINAMIDE ADENINE DINUCLEOTIDE (NAD(+)) PRECURSORS HAVE CAUSED FURTHER GROWTH OF NAM CONSUMPTION NOT ONLY FOR CLINICAL TREATMENTS, BUT ALSO AS A DIETARY SUPPLEMENT, RAISING CONCERNS ON THE SAFETY OF ITS LONG-TERM USE. HOWEVER, POSSIBLE ADVERSE EFFECTS AND THEIR MECHANISMS ARE POORLY UNDERSTOOD. HIGH-LEVEL NAM ADMINISTRATION CAN EXERT NEGATIVE EFFECTS THROUGH MULTIPLE ROUTES. FOR EXAMPLE, NAM BY ITSELF INHIBITS POLY(ADP-RIBOSE) POLYMERASES (PARPS), WHICH PROTECT GENOME INTEGRITY. ELEVATION OF THE NAD(+) POOL ALTERS CELLULAR ENERGY METABOLISM. MEANWHILE, HIGH-LEVEL NAM ALTERS CELLULAR METHYL METABOLISM AND AFFECTS METHYLATION OF DNA AND PROTEINS, LEADING TO CHANGES IN CELLULAR TRANSCRIPTOME AND PROTEOME. ALSO, METHYL METABOLITES OF NAM, NAMELY METHYLNICOTINAMIDE, ARE PREDICTED TO PLAY ROLES IN CERTAIN DISEASES AND CONDITIONS. IN THIS REVIEW, A COLLECTIVE LITERATURE SEARCH WAS PERFORMED TO PROVIDE A COMPREHENSIVE LIST OF POSSIBLE ADVERSE EFFECTS OF NAM AND TO PROVIDE UNDERSTANDING OF THEIR UNDERLYING MECHANISMS AND ASSESSMENT OF THE RAISED SAFETY CONCERNS. OUR REVIEW ASSURES SAFETY IN CURRENT USAGE LEVEL OF NAM, BUT ALSO FINDS POTENTIAL RISKS FOR EPIGENETIC ALTERATIONS ASSOCIATED WITH CHRONIC USE OF NAM AT HIGH DOSES. IT ALSO SUGGESTS DIRECTIONS OF THE FUTURE STUDIES TO ENSURE SAFER APPLICATION OF NAM. 2020 6 860 45 CHROMATIN MODIFICATIONS DURING REPAIR OF ENVIRONMENTAL EXPOSURE-INDUCED DNA DAMAGE: A POTENTIAL MECHANISM FOR STABLE EPIGENETIC ALTERATIONS. EXPOSURES TO ENVIRONMENTAL TOXICANTS AND TOXINS CAUSE EPIGENETIC CHANGES THAT LIKELY PLAY A ROLE IN THE DEVELOPMENT OF DISEASES ASSOCIATED WITH EXPOSURE. THE MECHANISM BEHIND THESE EXPOSURE-INDUCED EPIGENETIC CHANGES IS CURRENTLY UNKNOWN. ONE COMMONALITY BETWEEN MOST ENVIRONMENTAL EXPOSURES IS THAT THEY CAUSE DNA DAMAGE EITHER DIRECTLY OR THROUGH CAUSING AN INCREASE IN REACTIVE OXYGEN SPECIES, WHICH CAN DAMAGE DNA. LIKE TRANSCRIPTION, DNA DAMAGE REPAIR MUST OCCUR IN THE CONTEXT OF CHROMATIN REQUIRING BOTH HISTONE MODIFICATIONS AND ATP-DEPENDENT CHROMATIN REMODELING. THESE CHROMATIN CHANGES AID IN DNA DAMAGE ACCESSIBILITY AND SIGNALING. SEVERAL PROTEINS AND COMPLEXES INVOLVED IN EPIGENETIC SILENCING DURING BOTH DEVELOPMENT AND CANCER HAVE BEEN FOUND TO BE LOCALIZED TO SITES OF DNA DAMAGE. THE CHROMATIN-BASED RESPONSE TO DNA DAMAGE IS CONSIDERED A TRANSIENT EVENT, WITH CHROMATIN BEING RESTORED TO NORMAL AS DNA DAMAGE REPAIR IS COMPLETED. HOWEVER, IN INDIVIDUALS CHRONICALLY EXPOSED TO ENVIRONMENTAL TOXICANTS OR WITH CHRONIC INFLAMMATORY DISEASE, REPEATED DNA DAMAGE-INDUCED CHROMATIN REARRANGEMENT MAY ULTIMATELY LEAD TO PERMANENT EPIGENETIC ALTERATIONS. UNDERSTANDING THE MECHANISM BEHIND EXPOSURE-INDUCED EPIGENETIC CHANGES WILL ALLOW US TO DEVELOP STRATEGIES TO PREVENT OR REVERSE THESE CHANGES. THIS REVIEW FOCUSES ON EPIGENETIC CHANGES AND DNA DAMAGE INDUCED BY ENVIRONMENTAL EXPOSURES, THE CHROMATIN CHANGES THAT OCCUR AROUND SITES OF DNA DAMAGE, AND HOW THESE TRANSIENT CHROMATIN CHANGES MAY LEAD TO HERITABLE EPIGENETIC ALTERATIONS AT SITES OF CHRONIC EXPOSURE. 2014 7 4374 35 MISMATCH REPAIR PROTEINS RECRUIT DNA METHYLTRANSFERASE 1 TO SITES OF OXIDATIVE DNA DAMAGE. AT SITES OF CHRONIC INFLAMMATION, EPITHELIAL CELLS ARE EXPOSED TO HIGH LEVELS OF REACTIVE OXYGEN SPECIES AND UNDERGO CANCER-ASSOCIATED DNA METHYLATION CHANGES, SUGGESTING THAT INFLAMMATION MAY INITIATE EPIGENETIC ALTERATIONS. PREVIOUSLY, WE DEMONSTRATED THAT OXIDATIVE DAMAGE CAUSES EPIGENETIC SILENCING PROTEINS TO BECOME PART OF A LARGE COMPLEX THAT IS LOCALIZED TO GC-RICH REGIONS OF THE GENOME, INCLUDING PROMOTER CPG ISLANDS THAT ARE EPIGENETICALLY SILENCED IN CANCER. HOWEVER, WHETHER THESE PROTEINS WERE RECRUITED DIRECTLY TO DAMAGED DNA OR DURING THE DNA REPAIR PROCESS WAS UNKNOWN. HERE WE DEMONSTRATE THAT THE MISMATCH REPAIR PROTEIN HETERODIMER MSH2-MSH6 PARTICIPATES IN THE OXIDATIVE DAMAGE-INDUCED RECRUITMENT OF DNA METHYLTRANSFERASE 1 (DNMT1) TO CHROMATIN. HYDROGEN PEROXIDE TREATMENT INDUCES THE INTERACTION OF MSH2-MSH6 WITH DNMT1, SUGGESTING THAT THE RECRUITMENT IS THROUGH A PROTEIN-PROTEIN INTERACTION. IMPORTANTLY, THE REDUCTION IN TRANSCRIPTION FOR GENES WITH CPG ISLAND-CONTAINING PROMOTERS CAUSED BY OXIDATIVE DAMAGE IS ABROGATED BY KNOCKDOWN OF MSH6 AND/OR DNMT1. OUR FINDINGS PROVIDE EVIDENCE THAT THE ROLE OF DNMT1 AT SITES OF OXIDATIVE DAMAGE IS TO REDUCE TRANSCRIPTION, POTENTIALLY PREVENTING TRANSCRIPTION FROM INTERFERING WITH THE REPAIR PROCESS. THIS STUDY UNIQUELY BRINGS TOGETHER SEVERAL FACTORS THAT ARE KNOWN TO CONTRIBUTE TO COLON CANCER, NAMELY INFLAMMATION, MISMATCH REPAIR PROTEINS, AND EPIGENETIC CHANGES. 2016 8 4458 41 MOLECULAR MECHANISMS OF ALCOHOL-INDUCED COLORECTAL CARCINOGENESIS. THE ETIOLOGY OF COLORECTAL CANCER (CRC) IS COMPLEX. APPROXIMATELY, 10% OF INDIVIDUALS WITH CRC HAVE PREDISPOSING GERMLINE MUTATIONS THAT LEAD TO FAMILIAL CANCER SYNDROMES, WHEREAS MOST CRC PATIENTS HAVE SPORADIC CANCER RESULTING FROM A COMBINATION OF ENVIRONMENTAL AND GENETIC RISK FACTORS. IT HAS BECOME INCREASINGLY CLEAR THAT CHRONIC ALCOHOL CONSUMPTION IS ASSOCIATED WITH THE DEVELOPMENT OF SPORADIC CRC; HOWEVER, THE EXACT MECHANISMS BY WHICH ALCOHOL CONTRIBUTES TO COLORECTAL CARCINOGENESIS ARE LARGELY UNKNOWN. SEVERAL PROPOSED MECHANISMS FROM STUDIES IN CRC MODELS SUGGEST THAT ALCOHOL METABOLITES AND/OR ENZYMES ASSOCIATED WITH ALCOHOL METABOLISM ALTER CELLULAR REDOX BALANCE, CAUSE DNA DAMAGE, AND EPIGENETIC DYSREGULATION. IN ADDITION, ALCOHOL METABOLITES CAN CAUSE A DYSBIOTIC COLORECTAL MICROBIOME AND INTESTINAL PERMEABILITY, RESULTING IN BACTERIAL TRANSLOCATION, INFLAMMATION, AND IMMUNOSUPPRESSION. ALL OF THESE EFFECTS CAN INCREASE THE RISK OF DEVELOPING CRC. THIS REVIEW AIMS TO OUTLINE SOME OF THE MOST SIGNIFICANT AND RECENT FINDINGS ON THE MECHANISMS OF ALCOHOL IN COLORECTAL CARCINOGENESIS. WE EXAMINE THE EFFECT OF ALCOHOL ON THE GENERATION OF REACTIVE OXYGEN SPECIES, THE DEVELOPMENT OF GENOTOXIC STRESS, MODULATION OF ONE-CARBON METABOLISM, DISRUPTION OF THE MICROBIOME, AND IMMUNOSUPPRESSION. 2021 9 4942 35 PATERNAL OBESITY: HOW BAD IS IT FOR SPERM QUALITY AND PROGENY HEALTH? THERE IS SUBSTANTIAL EVIDENCE THAT PATERNAL OBESITY IS ASSOCIATED NOT ONLY WITH AN INCREASED INCIDENCE OF INFERTILITY, BUT ALSO WITH AN INCREASED RISK OF METABOLIC DISTURBANCE IN ADULT OFFSPRING. APPARENTLY, SEVERAL MECHANISMS MAY CONTRIBUTE TO THE SPERM QUALITY ALTERATIONS ASSOCIATED WITH PATERNAL OBESITY, SUCH AS PHYSIOLOGICAL/HORMONAL ALTERATIONS, OXIDATIVE STRESS, AND EPIGENETIC ALTERATIONS. ALONG THESE LINES, MODIFICATIONS OF HORMONAL PROFILES NAMELY REDUCED ANDROGEN LEVELS AND ELEVATED ESTROGEN LEVELS, WERE FOUND ASSOCIATED WITH LOWER SPERM CONCENTRATION AND SEMINAL VOLUME. ADDITIONALLY, OXIDATIVE STRESS IN TESTIS MAY INDUCE AN INCREASE OF THE PERCENTAGE OF SPERM WITH DNA FRAGMENTATION. THE LATTER, RELATE TO OTHER PECULIARITIES SUCH AS ALTERATION OF THE EMBRYONIC DEVELOPMENT, INCREASED RISK OF MISCARRIAGE, AND DEVELOPMENT OF CHRONIC MORBIDITY IN THE OFFSPRING, INCLUDING CHILDHOOD CANCERS. UNDOUBTEDLY, EPIGENETIC ALTERATIONS (IE, DNA METHYLATION, CHROMATIN MODIFICATIONS, AND SMALL RNA DEREGULATION) OF SPERM RELATED TO PATERNAL OBESITY AND THEIR CONSEQUENCES ON THE PROGENY ARE POORLY UNDERSTOOD DETERMINANTS OF PATERNAL OBESITY-INDUCED TRANSMISSION. IN THIS REVIEW, WE SUMMARIZE AND DISCUSS THE DATA AVAILABLE IN THE LITERATURE REGARDING THE BIOLOGICAL, PHYSIOLOGICAL, AND MOLECULAR CONSEQUENCES OF PATERNAL OBESITY ON MALE FERTILITY POTENTIAL AND ULTIMATELY PROGENY HEALTH. 2017 10 835 46 CHEMICAL CARCINOGEN MECHANISMS OF ACTION AND IMPLICATIONS FOR TESTING METHODOLOGY. CHEMICAL CARCINOGENS ARE OF TWO DISTINCT TYPES, DNA-REACTIVE AND EPIGENETIC. TESTING METHODOLOGY CAN BE DIRECTED TOWARD DETECTING EFFECTS OF BOTH TYPES OF CARCINOGEN. CARCINOGENS OF THE DNA-REACTIVE TYPE ARE DEFINED BY THE FORMATION OF COVALENTLY BOUND DNA ADDUCTS. THESE CHEMICALS HAVE STRUCTURES THAT YIELD ELECTROPHILIC REACTANTS EITHER DIRECTLY OR AFTER BIOACTIVATION. THESE AGENTS CAUSE GENOMIC ALTERATION IN THE STRUCTURE OR FUNCTION OF DNA IN THE TARGET CELL. IN ADDITION, THESE COMPOUNDS CAN EXERT OTHER CELLULAR AND TISSUE EPIGENETIC EFFECTS, SUCH AS CELL PROLIFERATION AND GROWTH PROMOTION. CARCINOGENS OF THE EPIGENETIC (PARAGENETIC) TYPE, IN CONTRAST, DO NOT REACT WITH DNA, BUT RATHER DISPLAY CELLULAR EFFECTS SUCH AS NEOPLASM GROWTH PROMOTION, CYTOTOXICITY, INHIBITION OF TISSUE GROWTH REGULATION, PEROXISOME PROLIFERATION, ENDOCRINE MODIFICATION, IMMUNOSUPPRESSION AND/OR SUSTAINED TISSUE ISCHEMIA THAT CAN BE THE BASIS FOR INCREASES IN NEOPLASIA. THEIR CHEMICAL STRUCTURE IS SUCH THAT THEY DO NOT GIVE RISE TO A REACTIVE ELECTROPHILE. THE TESTING METHODOLOGIES TO IDENTIFY EITHER TYPE FOLLOW A DECISION POINT APPROACH DESIGNED TO IDENTIFY POTENTIAL CARCINOGENICITY AND YIELD MECHANISTIC INFORMATION ON THE PRODUCTION OF EFFECTS THAT UNDERLIE CARCINOGENICITY. IT HAS 5 STAGES FOCUSING ON THE CHEMICAL STRUCTURE, DNA-REACTIVITY, EPIGENETIC EFFECTS, LIMITED BIOASSAYS AND FINALLY THE APPLICATION OF THE ACCELERATED BIOASSAY (ABA). ABA REQUIRES 40 WEEKS AND APPLIES THE USE OF SENSITIVE MARKERS FOR INDUCTION OF NEOPLASIA IN COMPARISON TO POSITIVE CONTROL COMPOUNDS FOR IMPORTANT ORGANS IN HUMAN CARCINOGENESIS. IT ENABLES DATA ACQUISITION OF THE ENTIRE CARCINOGENIC PROCESS DIRECTED TOWARD DEVELOPING MECHANISTIC INFORMATION. THE ABA HAS THE POTENTIAL TO REPLACE THE CHRONIC BIOASSAY IN RODENTS IN SOME CIRCUMSTANCES AND CAN SERVE AS AN ALTERNATIVE TO A CHRONIC BIOASSAY IN A SECOND SPECIES. 1996 11 3934 65 LIVER TUMOR INDUCTION. THE SIGNIFICANCE OF THE DEVELOPMENT OF NODULAR LIVER LESIONS IN RODENTS FOLLOWING THE ADMINISTRATION OF TEST AGENTS RAISES SEVERAL QUESTIONS WHICH COULD BE PLACED IN ONE OF TWO GENERAL CATEGORIES: DIAGNOSTIC AND INTERPRETATIONAL. FROM A DIAGNOSTIC POINT OF VIEW, THE PROPER CLASSIFICATION OF LIVER TUMORS INTO A BENIGN AND MALIGNANT CATEGORY HAS TO BE BASED ON THE DIRECT CORRELATION BETWEEN THE MORPHOLOGY AND THE BIOLOGIC BEHAVIOR OF THE LESIONS. THEREFORE, EXTREME CARE SHOULD BE TAKEN TO SEPARATE THE MALIGNANT TUMORS FROM THE BENIGN AND THE BENIGN NEOPLASIA FROM THE HYPERPLASIA. THE SUBSTITUTION OF THE TERM "NEOPLASTIC NODULE" FOR HYPERPLASTIC NODULE IN RATS IS MISLEADING. MOST OF THESE NODULES, WHEN INDUCED UNDER SPECIAL EXPERIMENTAL CONDITIONS, MAY REGRESS OR REMODEL AND THUS THEY ARE NOT NEOPLASTIC IN NATURE. CHRONIC CARCINOGENICITY BIOASSAYS SHOULD INCLUDE "STOP" TYPE OF TREATMENT LEAVING ENOUGH OF THE OBSERVATIONAL TIME TO ESTABLISH THE FATE OF INDUCED NODULAR LESIONS. THE INDUCTION OF HISTOCHEMICALLY CHANGED FOCI CAN SERVE ONLY AS AN INDICATION OF POTENTIAL HEPATOCARCINOGENICITY AND SHOULD NOT BE EQUATED WITH THE INDUCTION OF BONA FIDE CANCER. THE BIOLOGIC INTERPRETATION OF NODULAR LIVER LESIONS, ESPECIALLY IN MICE, NEEDS FURTHER SCRUTINY BECAUSE THESE LESIONS HAVE A TENDENCY TO DEVELOP SPONTANEOUSLY WITH HIGH INCIDENCE IN SOME STRAINS. THIS CHARACTERISTIC THEN RAISES THE QUESTION AS TO THE MECHANISM BY WHICH VARIOUS AGENTS AUGMENT AND/OR ACCELERATE THE DEVELOPMENT OF SUCH TUMORS. IS THIS ACTION PRIMARILY PROMOTING OR INITIATING IN NATURE OR DOES IT REPRESENT THE INDUCTION OF TUMORS DE NOVO? THE ANSWER TO THIS DILEMMA MAY HAVE A DECISIVE BEARING ON CARCINOGENIC RISK ASSESSMENT AND THE TYPE OF REGULATORY ACTION, SINCE THE PROMOTING AGENTS POSSESS A THRESHOLD EFFECT AND THE PROMOTED CHANGES MAY REGRESS FOLLOWING WITHDRAWAL OF TREATMENT. THE INTERPRETATION OF HEPATOCARCINOGENESIS IS FURTHER COMPLICATED BY THE FACT THAT SEVERAL FACTORS, SUCH AS SEX HORMONAL ENVIRONMENT, INCREASED MITOTIC ACTIVITY FOLLOWING AN EXCESSIVE LOSS OF PARENCHYMAL CELLS, DEGREE OF CALORIC INTAKE, ENZYMATIC COMPLEMENT, AND ANIMALS' AGE AT THE TIME OF THE EXPOSURE TO A TEST AGENT, MAY INFLUENCE THE OUTCOME OF LIVER TUMOR DEVELOPMENT BY MODULATING "INITIATION" AND/OR "PROMOTION" OF CARCINOGENESIS. BROAD FLUCTUATION IN THE HISTORIC INCIDENCE OF LIVER TUMORS FURTHER COMPOUNDS THE COMPLEXITY OF THE PROPER BIOASSAY INTERPRETATION. THE SPECIFICALLY DESIGNED EXPERIMENTS MAY HAVE THE OBJECTIVE TO EXPLORE PREDOMINANTLY THE INITIATING OR PROMOTING EFFECTS OF THE AGENT. SUCH PROTOCOLS SHOULD BE USED WHENEVER NECESSARY TO DIFFERENTIATE BETWEEN THESE TWO MECHANISMS OF ACTION. IN THE CAUCASIANS, THE "SPONTANEOUS" DEVELOPMENT OF THE PRIMARY HEPATOCELLULAR TUMORS IS RARE. THE MAJORITY OF THESE TUMORS ARE MALIGNANT AND RAPIDLY FATAL. ACCORDING TO SOME HUMAN PATHOLOGISTS, THE BENIGN VARIETY OF LIVER TUMORS IS RARE AND IT DOES NOT REPRESENT NECESSARILY A PREMALIGNANT STAGE IN TUMOR DEVELOPMENT. CARCINOMA OF THE LIVER MAY OCCUR IN INFANCY, ESPECIALLY IN MALES BEFORE THE AGE OF 2 YEARS. THIS SUGGESTS A GENETIC CAUSATION OR CARCINOGENIC EXPOSURE IN UTERO. ONE OF THE GEOGRAPHIC FACTORS WHICH SIGNIFICANTLY ENHANCES THE INCIDENCE OF HEPATOCELLULAR CARCINOMA IN HUMANS IS EXPOSURE TO AFLATOXIN B(1) WHICH IS APPARENTLY POTENTIATED BY CONCURRENT LIVER CIRRHOSIS. BECAUSE MANY MORE AGENTS HAVE BEEN FOUND TO BE HEPATOCARCINOGENIC IN MICE AND RATS THAN IN MEN, A QUESTION ARISES AS TO THE DIRECT RELEVANCE OF RODENT STUDIES TO HUMANS. A BALANCED ASSESSMENT OF THE CARCINOGENICITY OF THE AGENT COULD ONLY BE REACHED IN CONSIDERING BOTH THE PHARMACOKINETICS AND THE DEVELOPMENT OF MALIGNANT NEOPLASIA IN OTHER ORGANS. IN THE CASE OF POSITIVE CARCINOGENICITY ASSESSMENT, THE OUTCOME OF THE MUTAGENICITY BIOASSAYS CAN SUGGEST GENIC (GENOTOXIC) OR PARAGENIC (EPIGENETIC) MODE OF ACTION IN MAMMALIAN SYSTEMS. 1982 12 474 23 ARSENIC BIOTRANSFORMATION AS A CANCER PROMOTING FACTOR BY INDUCING DNA DAMAGE AND DISRUPTION OF REPAIR MECHANISMS. CHRONIC EXPOSURE TO ARSENIC IN DRINKING WATER POSES A MAJOR GLOBAL HEALTH CONCERN. POPULATIONS EXPOSED TO HIGH CONCENTRATIONS OF ARSENIC-CONTAMINATED DRINKING WATER SUFFER SERIOUS HEALTH CONSEQUENCES, INCLUDING ALARMING CANCER INCIDENCE AND DEATH RATES. ARSENIC IS BIOTRANSFORMED THROUGH SEQUENTIAL ADDITION OF METHYL GROUPS, ACQUIRED FROM S-ADENOSYLMETHIONINE (SAM). METABOLISM OF ARSENIC GENERATES A VARIETY OF GENOTOXIC AND CYTOTOXIC SPECIES, DAMAGING DNA DIRECTLY AND INDIRECTLY, THROUGH THE GENERATION OF REACTIVE OXIDATIVE SPECIES AND INDUCTION OF DNA ADDUCTS, STRAND BREAKS AND CROSS LINKS, AND INHIBITION OF THE DNA REPAIR PROCESS ITSELF. SINCE SAM IS THE METHYL GROUP DONOR USED BY DNA METHYLTRANSFERASES TO MAINTAIN NORMAL EPIGENETIC PATTERNS IN ALL HUMAN CELLS, ARSENIC IS ALSO POSTULATED TO AFFECT MAINTENANCE OF NORMAL DNA METHYLATION PATTERNS, CHROMATIN STRUCTURE, AND GENOMIC STABILITY. THE BIOLOGICAL PROCESSES UNDERLYING THE CANCER PROMOTING FACTORS OF ARSENIC METABOLISM, RELATED TO DNA DAMAGE AND REPAIR, WILL BE DISCUSSED HERE. 2011 13 6335 34 THE ROLE OF DNA METHYLATION IN THE PATHOGENESIS OF TYPE 2 DIABETES MELLITUS. DIABETES MELLITUS (DM) IS A CHRONIC CONDITION CHARACTERISED BY BETA CELL DYSFUNCTION AND PERSISTENT HYPERGLYCAEMIA. THE DISORDER CAN BE DUE TO THE ABSENCE OF ADEQUATE PANCREATIC INSULIN PRODUCTION OR A WEAK CELLULAR RESPONSE TO INSULIN SIGNALLING. AMONG THE THREE TYPES OF DM, NAMELY, TYPE 1 DM (T1DM), TYPE 2 DM (T2DM), AND GESTATIONAL DM (GDM); T2DM ACCOUNTS FOR ALMOST 90% OF DIABETES CASES WORLDWIDE.EPIGENETIC TRAITS ARE STABLY HERITABLE PHENOTYPES THAT RESULT FROM CERTAIN CHANGES THAT AFFECT GENE FUNCTION WITHOUT ALTERING THE GENE SEQUENCE. WHILE EPIGENETIC TRAITS ARE CONSIDERED REVERSIBLE MODIFICATIONS, THEY CAN BE INHERITED MITOTICALLY AND MEIOTICALLY. IN ADDITION, EPIGENETIC TRAITS CAN RANDOMLY ARISE IN RESPONSE TO ENVIRONMENTAL FACTORS OR CERTAIN GENETIC MUTATIONS OR LESIONS, SUCH AS THOSE AFFECTING THE ENZYMES THAT CATALYSE THE EPIGENETIC MODIFICATION. IN THIS REVIEW, WE FOCUS ON THE ROLE OF DNA METHYLATION, A TYPE OF EPIGENETIC MODIFICATION, IN THE PATHOGENESIS OF T2DM. 2020 14 6790 38 [DNA METHYLATION ANALYSIS IN ENVIRONMENTAL AND OCCUPATIONAL CANCER RESEARCH]. THE PRESENT PAPER REVIEWS RECENT LABORATORY METHODS AND EXPERIMENTAL EVIDENCE CONCERNING EPIGENETIC BIOMARKERS INVOLVED IN CARCINOGENESIS MECHANISMS. WE INTRODUCE DNA METHYLATION AND ITS ROLE IN GENE EXPRESSION CONTROL. DNA METHYLATION ANALYSIS MAY ALLOW TO IDENTIFY EARLY CHANGES LEADING TO CANCER AND OTHER CHRONIC DISEASES. WE DESCRIBE HERE STRATEGIES FOR LABORATORY ANALYSES AND THEIR POSSIBLE APPLICATIONS. WE EXAMINE RESULTS FROM RECENT EXPERIMENTAL STUDIES SUGGESTING THAT THE EFFECTS OF CERTAIN OCCUPATIONAL AGENTS ARE MEDIATED BY ALTERATIONS IN DNA METHYLATION. PLANNING AND CONDUCTING INVESTIGATIONS ON EXPOSED HUMAN SUBJECTS WILL ALLOW TO VERIFY WHETHER DNA METHYLATION CHANGES IDENTIFIED IN ANIMAL AND IN-VITRO STUDIES MAY BE USED AS EARLY-EFFECT AND SUSCEPTIBILITY BIOMARKERS. DNA METHYLATION ANALYSIS HAS THE POTENTIAL FOR FUTURE APPLICATIONS IN RISK ASSESSMENT AND PREVENTION PROGRAMS CONDUCTED ON SUBJECTS EXPOSED TO HUMAN CARCINOGENS. 2005 15 1168 52 CONTRIBUTION OF EPITHELIAL AND GUT MICROBIOME INFLAMMATORY BIOMARKERS TO THE IMPROVEMENT OF COLORECTAL CANCER PATIENTS' STRATIFICATION. IN ORDER TO ENSURE THAT PRIMARY ENDPOINTS OF CLINICAL STUDIES ARE ATTAINED, THE PATIENTS' STRATIFICATION IS AN IMPORTANT ASPECT. SELECTION CRITERIA INCLUDE AGE, GENDER, AND ALSO SPECIFIC BIOMARKERS, SUCH AS INFLAMMATION SCORES. THESE CRITERIA ARE NOT SUFFICIENT TO ACHIEVE A STRAIGHTFORWARD SELECTION, HOWEVER, IN CASE OF MULTIFACTORIAL DISEASES, WITH UNKNOWN OR PARTIALLY IDENTIFIED MECHANISMS, OCCASIONALLY INCLUDING HOST FACTORS, AND THE MICROBIOME. IN THESE CASES, THE EFFICACY OF INTERVENTIONS IS DIFFICULT TO PREDICT, AND AS A RESULT, THE SELECTION OF SUBJECTS IS OFTEN RANDOM. COLORECTAL CANCER (CRC) IS A HIGHLY HETEROGENEOUS DISEASE, WITH VARIABLE CLINICAL FEATURES, OUTCOMES, AND RESPONSE TO THERAPY; THE CRC ONSET AND PROGRESS INVOLVES MULTIPLE SEQUENTIAL STEPS WITH ACCUMULATION OF GENETIC ALTERATIONS, NAMELY, MUTATIONS, GENE AMPLIFICATION, AND EPIGENETIC CHANGES. THE GUT MICROBES, EITHER EUBIOTIC OR DYSBIOTIC, COULD INFLUENCE THE CRC EVOLUTION THROUGH A COMPLEX AND VERSATILE CROSSTALK WITH THE INTESTINAL AND IMMUNE CELLS, PERMANENTLY CHANGING THE TUMOR MICROENVIRONMENT. THERE HAVE BEEN SIGNIFICANT ADVANCES IN THE DEVELOPMENT OF PERSONALIZED APPROACHES FOR CRC SCREENING, TREATMENT, AND POTENTIAL PREVENTION. ADVANCES IN MOLECULAR TECHNIQUES BRING NEW CRITERIA FOR PATIENTS' STRATIFICATION-MUTATIONAL ANALYSIS AT THE TIME OF DIAGNOSIS TO GUIDE TREATMENT, FOR EXAMPLE. GUT MICROBIOME HAS EMERGED AS THE MAIN TRIGGER OF GUT MUCOSAL HOMEOSTASIS. THIS MAY IMPACT CANCER SUSCEPTIBILITY THROUGH MAINTENANCE OF THE EPITHELIAL/MUCUS BARRIER AND PRODUCTION OF PROTECTIVE METABOLITES, SUCH AS SHORT-CHAIN FATTY ACIDS (SCFAS) VIA INTERACTIONS WITH THE HOSTS' DIET AND METABOLISM. MICROBIOME DYSBIOSIS LEADS TO THE ENRICHMENT OF CANCER-PROMOTING BACTERIAL POPULATIONS, LOSS OF PROTECTIVE POPULATIONS OR MAINTAINING AN INFLAMMATORY CHRONIC STATE, ALL OF WHICH CONTRIBUTE TO THE DEVELOPMENT AND PROGRESSION OF CRC. MEANWHILE, VARIATIONS IN PATIENT RESPONSES TO ANTI-CANCER IMMUNO- AND CHEMOTHERAPIES WERE ALSO LINKED TO INTER-INDIVIDUAL DIFFERENCES IN INTESTINE MICROBIOMES. THE AUTHORS AIM TO HIGHLIGHT THE CONTRIBUTION OF EPITHELIAL AND GUT MICROBIOME INFLAMMATORY BIOMARKERS IN THE IMPROVEMENT OF CRC PATIENTS' STRATIFICATION TOWARDS A PERSONALIZED APPROACH OF EARLY DIAGNOSIS AND TREATMENT. 2021 16 5494 22 REVIEW OF THE MOLECULAR MECHANISMS IN WOUND HEALING: NEW THERAPEUTIC TARGETS? THE RESTORATION OF THE SKIN BARRIER IN ACUTE AND CHRONIC WOUNDS IS CONTROLLED BY SEVERAL MOLECULAR MECHANISMS THAT SYNERGISTICALLY REGULATE CELL KINETICS, ENZYMATIC FUNCTIONS, AND NEUROVASCULAR ACTIVATION. THESE PATHWAYS INCLUDE GENETIC AND EPIGENETIC ACTIVATION, WHICH MODULATE PHYSIOLOGICAL WOUND HEALING. OUR REVIEW DESCRIBES THE GENETIC BACKGROUND OF SKIN REPAIR, NAMELY TRANSCRIPTION-INDEPENDENT DIFFUSIBLE DAMAGE SIGNALS, INDIVIDUAL VARIABILITY, EPIGENETIC MECHANISM, CONTROLLED QUALITATIVE TRAITS, POST-TRANSLATIONAL MECHANISMS, ANTIOXIDANTS, NUTRIENTS, DNA MODIFICATIONS, BACTERIA ACTIVATION, MITOCHONDRIAL ACTIVITY, AND OXIDATIVE STRESS. THE DNA BACKGROUND MODULATING SKIN RESTORATION COULD BE USED TO PLAN NEW DIAGNOSTICS AND THERAPEUTICS. 2017 17 4119 56 MECHANISMS OF CADMIUM CARCINOGENICITY IN THE GASTROINTESTINAL TRACT. CANCER, A SERIOUS PUBLIC HEALTH PROBLEM IN WORLDWIDE, RESULTS FROM AN EXCESSIVE AND UNCONTROLLED PROLIFERATION OF THE BODY CELLS WITHOUT OBVIOUS PHYSIOLOGICAL DEMANDS OF ORGANS. THE GASTROINTESTINAL TRACT, INCLUDING THE ESOPHAGUS, STOMACH AND INTESTINE, IS A UNIQUE ORGAN SYSTEM. IT HAS THE HIGHEST CANCER INCIDENCE AND CANCER- RELATED MORTALITY IN THE BODY AND IS INFLUENCEED BY BOTH GENETIC AND ENVIRONMENTAL FACTORS. AMONG THE VARIOUS CHEMICAL ELEMENTS RECOGNIZED IN THE NATURE, SOME OF THEM INCLUDING ZINC, IRON, COBALT, AND COPPER HAVE ESSENTIAL ROLES IN THE VARIOUS BIOCHEMICAL AND PHYSIOLOGICAL PROCESSES, BUT ONLY AT LOW LEVELS AND OTHERS SUCH AS CADMIUM, LEAD, MERCURY, ARSENIC, AND NICKEL ARE CONSIDERED AS THREATS FOR HUMAN HEALTH ESPECIALLY WITH CHRONIC EXPOSURE AT HIGH LEVELS. CADMIUM, AN ENVIRONMENT CONTAMINANT, CANNOT BE DESTROYED IN NATURE. THROUGH IMPAIRMENT OF VITAMIN D METABOLISM IN THE KIDNEY IT CAUSES NEPHROTOXICITY AND SUBSEQUENTLY BONE METABOLISM IMPAIRMENT AND FRAGILITY. THE MAJOR MECHANISMS INVOLVED IN CADMIUM CARCINOGENESIS COULD BE RELATED TO THE SUPPRESSION OF GENE EXPRESSION, INHIBITION OF DNA DAMAGE REPAIR, INHIBITION OF APOPTOSIS, AND INDUCTION OF OXIDATIVE STRESS. IN ADDITION, CADMIUM MAY ACT THROUGH ABERRANT DNA METHYLATION. CADMIUM AFFECTS MULTIPLE CELLULAR PROCESSES, INCLUDING SIGNAL TRANSDUCTION PATHWAYS, CELL PROLIFERATION, DIFFERENTIATION, AND APOPTOSIS. DOWN-REGULATION OF METHYLTRANSFERASES ENZYMES AND REDUCTION OF DNA METHYLATION HAVE BEEN STATED AS EPIGENETIC EFFECTS OF CADMIUM. FURTHERMORE, INCREASING INTRACELLULAR FREE CALCIUM ION LEVELS INDUCES NEURONAL APOPTOSIS IN ADDITION TO OTHER DELETERIOUS INFLUENCE ON THE STABILITY OF THE GENOME. 2015 18 837 67 CHEMICALLY INDUCED RENAL TUBULE TUMORS IN THE LABORATORY RAT AND MOUSE: REVIEW OF THE NCI/NTP DATABASE AND CATEGORIZATION OF RENAL CARCINOGENS BASED ON MECHANISTIC INFORMATION. THE INCIDENCE OF RENAL TUBULE CARCINOGENESIS IN MALE AND FEMALE RATS OR MICE WITH 69 CHEMICALS FROM THE 513 BIOASSAYS CONDUCTED TO DATE BY THE NCI/NTP HAS BEEN COLLATED, THE CHEMICALS CATEGORIZED, AND THE RELATIONSHIP BETWEEN CARCINOGENESIS AND RENAL TUBULE HYPERPLASIA AND EXACERBATION OF THE SPONTANEOUS, AGE-RELATED RODENT DISEASE CHRONIC PROGRESSIVE NEPHROPATHY (CPN) EXAMINED. WHERE INFORMATION ON MECHANISM OR MODE OF ACTION EXISTS, THE CHEMICALS HAVE BEEN CATEGORIZED BASED ON THEIR ABILITY TO DIRECTLY OR INDIRECTLY INTERACT WITH RENAL DNA, OR ON THEIR ACTIVITY VIA EPIGENETIC PATHWAYS INVOLVING EITHER DIRECT OR INDIRECT CYTOTOXICITY WITH REGENERATIVE HYPERPLASIA, OR EXACERBATION OF CPN. NINE CHEMICALS WERE IDENTIFIED AS DIRECTLY INTERACTING WITH DNA, WITH SIX OF THESE PRODUCING RENAL TUBULE TUMORS AT HIGH INCIDENCE IN RATS OF BOTH SEXES, AND IN SOME CASES ALSO IN MICE. OCHRATOXIN A WAS THE MOST POTENT COMPOUND IN THIS GROUP, PRODUCING A HIGH TUMOR INCIDENCE AT VERY LOW DOSES, OFTEN WITH METASTASIS. THREE CHEMICALS WERE DISCUSSED IN THE CONTEXT OF INDIRECT DNA DAMAGE MEDIATED BY AN OXIDATIVE FREE RADICAL MECHANISM, ONE OF THESE BEING FROM THE NTP DATABASE. A THIRD CATEGORY INCLUDED FOUR CHEMICALS THAT HAD THE POTENTIAL TO CAUSE DNA DAMAGE FOLLOWING CONJUGATION WITH GLUTATHIONE AND SUBSEQUENT ENZYMATIC ACTIVATION TO A REACTIVE SPECIES, USUALLY A THIOL-CONTAINING ENTITY. TWO CHEMICALS WERE ALLOCATED INTO THE CATEGORY INVOLVING A DIRECT CYTOTOXIC ACTION ON THE RENAL TUBULE FOLLOWED BY SUSTAINED COMPENSATORY CELL PROLIFERATION, WHILE NINE WERE INCLUDED IN A GROUP WHERE THE CELL LOSS AND SUSTAINED INCREASE IN RENAL TUBULE CELL TURNOVER WERE DEPENDENT ON LYSOSOMAL ACCUMULATION OF THE MALE RAT-SPECIFIC PROTEIN, ALPHA2MU-GLOBULIN. IN A SIXTH CATEGORY, MORPHOLOGIC EVIDENCE ON TWO CHEMICALS INDICATED THAT THE RENAL TUMORS WERE A CONSEQUENCE OF EXACERBATED CPN. FOR THE REMAINING CHEMICALS, THERE WERE NO PERTINENT DATA ENABLING ASSIGNMENT TO A MECHANISTIC CATEGORY. ACCORDINGLY, THESE CHEMICALS, ACTING THROUGH AN AS YET UNKNOWN MECHANISM, WERE GROUPED AS EITHER BEING ASSOCIATED WITH AN ENHANCEMENT OF CPN (CATEGORY 7, 16 CHEMICALS), OR NOT ASSOCIATED WITH ENHANCED CPN (CATEGORY 8, 4 CHEMICALS). A NINTH CATEGORY DEALT WITH 11 CHEMICALS THAT WERE REGARDED AS PRODUCING INCREASES IN RENAL TUBULE TUMORS THAT DID NOT REACH STATISTICAL SIGNIFICANCE. A 10TH CATEGORY DISCUSSED 6 CHEMICALS THAT INDUCED RENAL TUMORS IN MICE BUT NOT IN RATS, PLUS 8 CHEMICALS THAT PRODUCED A LOW INCIDENCE OF RENAL TUBULE TUMORS IN MICE THAT DID NOT REACH STATISTICAL SIGNIFICANCE. AS MORE MECHANISTIC DATA ARE GENERATED, SOME CHEMICALS WILL INEVITABLY BE PLACED IN DIFFERENT GROUPS, PARTICULARLY THOSE FROM CATEGORIES 7 AND 8. A LARGE NUMBER OF CHEMICALS IN THE SERIES EXACERBATED CPN, BUT THOSE IN CATEGORY 7 ESPECIALLY MAY BE CANDIDATES FOR INCLUSION IN CATEGORY 6 WHEN FURTHER INFORMATION IS GLEANED FROM THE RELEVANT NTP STUDIES. ALSO, NEW DATA ON SPECIFIC CHEMICALS WILL PROBABLY EXPAND CATEGORY 5 AS CYTOTOXICITY AND CELL REGENERATION ARE IDENTIFIED AS OBLIGATORY STEPS IN RENAL CARCINOGENESIS IN MORE CASES. ADDITIONAL CONFIRMATORY OUTCOMES ARISING FROM THIS REVIEW ARE THAT METASTASES FROM RENAL TUBULE TUMORS, WHILE ENCOUNTERED WITH CHEMICALS CAUSING DNA DAMAGE, ARE RARE WITH THOSE ACTING THROUGH AN EPIGENETIC PATHWAY, WITH THE EXCEPTION BEING FUMONISIN B1; THAT MALE RATS AND MICE ARE GENERALLY MORE SUSCEPTIBLE THAN FEMALE RATS AND MICE TO CHEMICAL INDUCTION OF RENAL TUBULE TUMORS; AND THAT A BACKGROUND OF ATYPICAL TUBULE HYPERPLASIA IS A USEFUL INDICATOR REFLECTING A CHEMICALLY ASSOCIATED RENAL TUBULE TUMOR RESPONSE. WITH RESPECT TO RENAL TUBULE TUMORS AND HUMAN RISK ASSESSMENT, CHEMICALS IN CATEGORIES 1 AND 2, AND POSSIBLY 3, WOULD CURRENTLY BE JUDGED BY LINEAR DEFAULT METHODS; CHEMICALS IN CATEGORY 4 (AND PROBABLY SOME IN CATEGORY 3) AS EXHIBITING A THRESHOLD OF ACTIVITY WARRANTING THE BENCHMARK APPROACH; AND THOSE IN CATEGORIES 5 AND 6 AS REPRESENTING MECHANISMS THAT HAVE NO RELEVANCE FOR EXTRAPOLATION TO HUMANS. 2004 19 126 67 A TOXICOGENOMICS APPROACH TO IDENTIFY NEW PLAUSIBLE EPIGENETIC MECHANISMS OF OCHRATOXIN A CARCINOGENICITY IN RAT. OCHRATOXIN A (OTA) IS A MYCOTOXIN OCCURRING NATURALLY IN A WIDE RANGE OF FOOD COMMODITIES. IN ANIMALS, IT HAS BEEN SHOWN TO CAUSE A VARIETY OF ADVERSE EFFECTS, NEPHROCARCINOGENICITY BEING THE MOST PROMINENT. BECAUSE OF ITS HIGH TOXIC POTENCY AND THE CONTINUOUS EXPOSURE OF THE HUMAN POPULATION, OTA HAS RAISED PUBLIC HEALTH CONCERNS. THERE IS SIGNIFICANT DEBATE ON HOW TO USE THE RAT CARCINOGENICITY DATA TO ASSESS THE POTENTIAL RISK TO HUMANS. IN THIS CONTEXT, THE QUESTION OF THE MECHANISM OF ACTION OF OTA APPEARS OF KEY IMPORTANCE AND WAS STUDIED THROUGH THE APPLICATION OF A TOXICOGENOMICS APPROACH. MALE FISCHER RATS WERE FED OTA FOR UP TO 2 YEARS. RENAL TUMORS WERE DISCOVERED DURING THE LAST 6 MONTHS OF THE STUDY. THE TOTAL TUMOR INCIDENCE REACHED 25% AT THE END OF THE STUDY. GENE EXPRESSION PROFILE WAS ANALYZED IN GROUPS OF ANIMALS TAKEN IN INTERVALS FROM 7 DAYS TO 12 MONTHS. TISSUE-SPECIFIC RESPONSES WERE OBSERVED IN KIDNEY VERSUS LIVER. FOR SELECTED GENES, MICROARRAY DATA WERE CONFIRMED AT BOTH MRNA AND PROTEIN LEVELS. IN KIDNEY, SEVERAL GENES KNOWN AS MARKERS OF KIDNEY INJURY AND CELL REGENERATION WERE SIGNIFICANTLY MODULATED BY OTA. THE EXPRESSION OF GENES KNOWN TO BE INVOLVED IN DNA SYNTHESIS AND REPAIR, OR GENES INDUCED AS A RESULT OF DNA DAMAGE, WAS ONLY MARGINALLY MODULATED. VERY LITTLE OR NO EFFECT WAS FOUND AMONGST GENES ASSOCIATED WITH APOPTOSIS. ALTERATIONS OF GENE EXPRESSION INDICATING EFFECTS ON CALCIUM HOMEOSTASIS AND A DISRUPTION OF PATHWAYS REGULATED BY THE TRANSCRIPTION FACTORS HEPATOCYTE NUCLEAR FACTOR 4 ALPHA (HNF4ALPHA) AND NUCLEAR FACTOR-ERYTHROID 2-RELATED FACTOR 2 (NRF2) WERE OBSERVED IN THE KIDNEY BUT NOT IN THE LIVER. PREVIOUS DATA HAVE SUGGESTED THAT A REDUCTION IN HNF4ALPHA MAY BE ASSOCIATED WITH NEPHROCARCINOGENICITY. MANY NRF2-REGULATED GENES ARE INVOLVED IN CHEMICAL DETOXICATION AND ANTIOXIDANT DEFENSE. THE DEPLETION OF THESE GENES IS LIKELY TO IMPAIR THE DEFENSE POTENTIAL OF THE CELLS, RESULTING IN CHRONIC ELEVATION OF OXIDATIVE STRESS IN THE KIDNEY. THE INHIBITION OF DEFENSE MECHANISM APPEARS AS A HIGHLY PLAUSIBLE NEW MECHANISM, WHICH COULD CONTRIBUTE TO OTA CARCINOGENICITY. 2006 20 45 35 A COMPREHENSIVE REVIEW ON RNA INTERFERENCE-MEDIATED TARGETING OF INTERLEUKINS AND ITS POTENTIAL THERAPEUTIC IMPLICATIONS IN COLON CANCER. COLON CANCER IS THE WORLD'S FOURTH LEADING CAUSE OF DEATH. IT IS CANCER OF THE LATTER PART OF THE LARGE INTESTINE, I.E. THE COLON. CHRONIC INFLAMMATION OVER A LONG PERIOD ALSO LEADS TO THE DEVELOPMENT OF CANCER. CANCER IN THE COLON REGION IS ARDUOUS TO DIAGNOSE AND IS DETECTED AT A LATER STAGE WHEN IT METASTASIZES TO OTHER PARTS OF THE BODY LIKE THE LIVER, LUNGS, PERITONEUM, ETC. COLON CANCER IS A GREAT EXAMPLE OF SOLID TUMOURS ASSOCIATED WITH CHRONIC INFLAMMATION. ALTHOUGH CONVENTIONAL THERAPIES ARE EFFECTIVE, THEY LOSE THEIR EFFECTIVENESS BEYOND A CERTAIN POINT. RELAPSE OF THE DISEASE OCCURS FREQUENTLY. RNA INTERFERENCE (RNAI) IS EMERGING AS A GREAT TOOL TO SPECIFICALLY ATTACK THE CANCER CELLS OF A TARGET SITE LIKE THE COLON. RNAI DEALS WITH EPIGENETIC CHANGES MADE IN THE DEFECTIVE CELLS WHICH ULTIMATELY LEADS TO THEIR DEATH WITHOUT HARMING THE HEALTHY CELLS. IN THIS REVIEW, TWO TYPES OF EPIGENETIC MODULATORS HAVE BEEN CONSIDERED, NAMELY SIRNA AND MIRNA, AND THEIR EFFECT ON INTERLEUKINS. INTERLEUKINS, A CLASS OF CYTOKINES, ARE MAJOR INFLAMMATORY RESPONSES OF THE BODY THAT ARE RELEASED BY IMMUNE CELLS LIKE LEUKOCYTES AND MACROPHAGES. SOME OF THESE INTERLEUKINS ARE PRO-INFLAMMATORY, THEREBY PROMOTING INFLAMMATION WHICH EVENTUALLY CAUSES CANCER. RNAI CAN PREVENT COLON CANCER BY INHIBITING PRO-INFLAMMATORY INTERLEUKINS. 2023