1 1099 128 COLONIC CARCINOGENESIS IN IBD: MOLECULAR EVENTS. PATIENTS WITH ULCERATIVE COLITIS (UC) AND CROHN'S DISEASE (CD) ARE AT INCREASED RISK OF DEVELOPING INTESTINAL CANCERS VIA MECHANISMS THAT REMAIN INCOMPLETELY UNDERSTOOD. SEVERAL EVIDENCES SUGGEST A CAUSAL LINK BETWEEN CHRONIC INFLAMMATION AND THE DEVELOPMENT OF CANCER IN THE GASTROINTESTINAL TRACT. IN FACT, PATIENTS WITH UC ARE EXPOSED TO REPEATED EPISODES OF INFLAMMATION THAT PREDISPOSE TO VARIOUS TUMORIGENIC EVENTS AND THE SEQUENCE OF THESE EVENTS ARE DIFFERENT FROM THOSE THAT CONTRIBUTE TO DEVELOP A SPORADIC COLORECTAL CANCER. IN UC CARCINOGENESIS THE EARLY EVENTS ARE REPRESENTED BY DNA METHYLATION THAT PRODUCE AN INHIBITION OF ONCO-SUPPRESSOR GENES, MUTATION OF P53, ANEUPLOIDY AND MICROSATELLITE INSTABILITY. HYPERMETHYLATION OF TUMOR SUPPRESSORS AND DNA MISMATCH REPAIR GENE PROMOTER REGIONS, IS AN EPIGENETIC MECHANISM OF GENE SILENCING THAT CONTRIBUTES TO TUMORIGENESIS AND MIGHT REPRESENT THE FIRST STEP IN INFLAMMATORY CARCINOGENESIS. P53 IS FREQUENTLY MUTATED IN THE EARLY STAGES OF UC-ASSOCIATED CANCER, IN 33-67% OF PATIENTS WITH DYSPLASIA AND IN 83-95% OF UC RELATED CANCER PATIENTS. MOREOVER, ANEUPLOIDY IS AN INDEPENDENT RISK FACTOR FOR FORTHCOMING CARCINOGENESIS IN UC FINALLY, THE INCONSISTENCY BETWEEN THE HIGH CUMULATIVE RATE OF DYSPLASIA IN UC AND THE RELATIVELY LOWER INCIDENCE OF INVASIVE CANCER RAISES THE QUESTION ABOUT THE MECHANISMS OF IMMUNOSURVEILLANCE THAT MAY PREVENT MALIGNANT PROGRESSION OF NEOPLASM IN THE COLON IN MOST CASES. CO-STIMULATORY MOLECULE CD80 UP-REGULATION IN COLONIC MUCOSA IN UC DYSPLASIA MAY BE ONE OF THESE MECHANISM. 2011 2 2994 30 GENETIC PATHOGENESIS OF INFLAMMATION-ASSOCIATED CANCERS IN DIGESTIVE ORGANS. EPIDEMIOLOGICAL, CLINICAL, AND BIOLOGICAL STUDIES CONVINCINGLY DEMONSTRATE THAT CHRONIC INFLAMMATION PREDISPOSES TO THE DEVELOPMENT OF HUMAN CANCERS. IN DIGESTIVE ORGANS, INFLAMMATION-ASSOCIATED CANCERS INCLUDE COLITIS-ASSOCIATED COLORECTAL CANCERS, HELICOBACTER PYLORI-ASSOCIATED GASTRIC CANCER, AS WELL AS BARRETT'S ESOPHAGUS AND ESOPHAGEAL ADENOCARCINOMA ASSOCIATED WITH CHRONIC DUODENOGASTRIC-ESOPHAGEAL REFLUX. CANCER IS A GENOMIC DISEASE, AND STEPWISE ACCUMULATION OF GENETIC AND EPIGENETIC ALTERATIONS OF TUMOR-RELATED GENES LEADS TO THE DEVELOPMENT OF TUMOR CELLS. RECENT GENOME ANALYSES SHOW THAT GENETIC ALTERATIONS, WHICH ARE EVOKED BY INFLAMMATION, ARE LATENTLY ACCUMULATED IN INFLAMED EPITHELIAL CELLS OF DIGESTIVE ORGANS. PRODUCTION OF REACTIVE OXYGEN AND ABERRANT EXPRESSION OF ACTIVATION-INDUCED CYTIDINE DEAMINASE, A NUCLEOTIDE-EDITING ENZYME, COULD BE INDUCED IN INFLAMED GASTROINTESTINAL EPITHELIAL CELLS AND PLAY A ROLE AS A GENOMIC MODULATOR OF INFLAMMATION-ASSOCIATED CARCINOGENESIS. UNDERSTANDING THE MOLECULAR LINKAGE BETWEEN INFLAMMATION AND GENETIC ALTERATIONS WILL OPEN UP A NEW FIELD OF TUMOR BIOLOGY AND PROVIDE A NOVEL STRATEGY FOR THE PREVENTION OF INFLAMMATION-ASSOCIATED TUMORIGENESIS. 2021 3 925 34 CHRONIC INFLAMMATION INDUCES A NOVEL EPIGENETIC PROGRAM THAT IS CONSERVED IN INTESTINAL ADENOMAS AND IN COLORECTAL CANCER. CHRONIC INFLAMMATION REPRESENTS A MAJOR RISK FACTOR FOR TUMOR FORMATION, BUT THE UNDERLYING MECHANISMS HAVE REMAINED LARGELY UNKNOWN. EPIGENETIC MECHANISMS CAN RECORD THE EFFECTS OF ENVIRONMENTAL CHALLENGES ON THE GENOME LEVEL AND COULD THEREFORE PLAY AN IMPORTANT ROLE IN THE PATHOGENESIS OF INFLAMMATION-ASSOCIATED TUMORS. USING SINGLE-BASE METHYLATION MAPS AND TRANSCRIPTOME ANALYSES OF A COLITIS-INDUCED MOUSE COLON CANCER MODEL, WE IDENTIFIED A NOVEL EPIGENETIC PROGRAM THAT IS CHARACTERIZED BY HYPERMETHYLATION OF DNA METHYLATION VALLEYS THAT ARE CHARACTERIZED BY LOW CPG DENSITY AND ACTIVE CHROMATIN MARKS. THIS PROGRAM IS CONSERVED AND FUNCTIONAL IN MOUSE INTESTINAL ADENOMAS AND RESULTS IN SILENCING OF ACTIVE INTESTINAL GENES THAT ARE INVOLVED IN GASTROINTESTINAL HOMEOSTASIS AND INJURY RESPONSE. FURTHER ANALYSES REVEAL THAT THE PROGRAM REPRESENTS A PROMINENT FEATURE OF HUMAN COLORECTAL CANCER AND CAN BE USED TO CORRECTLY CLASSIFY COLORECTAL CANCER SAMPLES WITH HIGH ACCURACY. TOGETHER, OUR RESULTS SHOW THAT INFLAMMATORY SIGNALS ESTABLISH A NOVEL EPIGENETIC PROGRAM THAT SILENCES A SPECIFIC SET OF GENES THAT CONTRIBUTE TO INFLAMMATION-INDUCED CELLULAR TRANSFORMATION. 2015 4 2122 33 EPIGENETIC IMPACT OF INFECTION ON CARCINOGENESIS: MECHANISMS AND APPLICATIONS. VIRAL AND BACTERIAL INFECTIONS ARE INVOLVED IN THE DEVELOPMENT OF HUMAN CANCERS, SUCH AS LIVER, NASOPHARYNGEAL, CERVICAL, HEAD AND NECK, AND GASTRIC CANCERS. ABERRANT DNA METHYLATION IS FREQUENTLY PRESENT IN THESE CANCERS, AND SOME OF THE ABERRANTLY METHYLATED GENES ARE CAUSALLY INVOLVED IN CANCER DEVELOPMENT AND PROGRESSION. NOTABLY, ABERRANT DNA METHYLATION CAN BE PRESENT EVEN IN NON-CANCEROUS OR PRECANCEROUS TISSUES, AND ITS LEVELS CORRELATE WITH THE RISK OF CANCER DEVELOPMENT, PRODUCING A SO-CALLED 'EPIGENETIC FIELD FOR CANCERIZATION'. MECHANISTICALLY, MOST VIRAL OR BACTERIAL INFECTIONS INDUCE DNA METHYLATION INDIRECTLY VIA CHRONIC INFLAMMATION, BUT RECENT STUDIES HAVE INDICATED THAT SOME VIRUSES HAVE DIRECT EFFECTS ON THE EPIGENETIC MACHINERY OF HOST CELLS. FROM A TRANSLATIONAL VIEWPOINT, A RECENT MULTICENTER PROSPECTIVE COHORT STUDY DEMONSTRATED THAT ASSESSMENT OF THE EXTENT OF ALTERATIONS IN DNA METHYLATION IN NON-CANCEROUS TISSUES CAN BE USED TO PREDICT CANCER RISK. FURTHERMORE, SUPPRESSION OF ABERRANT DNA METHYLATION WAS SHOWN TO BE A USEFUL STRATEGY FOR CANCER PREVENTION IN AN ANIMAL MODEL. HERE, WE REVIEW THE INVOLVEMENT OF ABERRANT DNA METHYLATION IN VARIOUS TYPES OF INFECTION-ASSOCIATED CANCERS, ALONG WITH INDIVIDUAL INDUCTION MECHANISMS, AND WE DISCUSS THE APPLICATION OF THESE FINDINGS FOR CANCER PREVENTION, DIAGNOSIS, AND THERAPY. 2016 5 4671 39 NEW INSIGHTS INTO THE MECHANISM OF ACTION OF ASPIRIN IN THE PREVENTION OF COLORECTAL NEOPLASIA. THE RESULTS OF CLINICAL STUDIES HAVE SHOWN THAT THE CHRONIC ADMINISTRATION OF ASPIRIN, EVEN AT THE LOWDOSES (75-100 MG DAILY) RECOMMENDED FOR THE PREVENTION OF CARDIOVASCULAR DISEASE, IS ASSOCIATED WITH A REDUCTION OF CANCER INCIDENCE AND MORTALITY, IN PARTICULAR COLORECTAL CANCER (CRC). THE MECHANISM OF ACTION OF ASPIRIN AS AN ANTINEOPLASTIC AGENT REMAINS CONTROVERSIAL. HOWEVER, DATA OF CLINICAL PHARMACOLOGY AND SEVERAL FEATURES OF THE CHEMOPREVENTIVE EFFECT OF ASPIRIN, EMERGED FROM CLINICAL TRIALS, SUGGEST THAT THE ANTIPLATELET EFFECT OF ASPIRIN PLAYS A CENTRAL ROLE IN ITS ANTICANCER EFFECTS. IN ADDITION TO THEIR CONTRIBUTION TO TUMOR METASTASIS, PLATELETS MAY PLAY A ROLE IN THE EARLY PHASES OF TUMORIGENESIS. IN RESPONSE TO LIFESTYLE AND ENVIRONMENT FACTORS, INTESTINAL EPITHELIAL DAMAGE/ DYSFUNCTION MAY BE ASSOCIATED WITH PLATELET ACTIVATION, INITIALLY AS A MECHANISM TO REPAIR THE DAMAGE. HOWEVER, IF THE PLATELET RESPONSE IS UNCONSTRAINED, IT MAY CONTRIBUTE TO THE DEVELOPMENT OF CHRONIC INFLAMMATION. ALTOGETHER THESE EVENTS LEAD TO ALTER THE NORMAL FUNCTIONS OF INTESTINAL EPITHELIAL CELLS AND MAY TRANSLATE INTO CELLULAR TRANSFORMATION THROUGH SEVERAL MECHANISMS, INCLUDING THE OVEREXPRESSION OF CYCLOOXYGENASE(COX)-2 AND EPIDERMAL GROWTH FACTOR RECEPTOR (EGFR), WHICH ARE CONSIDERED EARLY EVENTS IN COLORECTAL TUMORIGENESIS. THUS, ANTIPLATELET AGENTS MAY PLAY A ROLE IN THE PREVENTION OF CRC BY MODIFYING EPIGENETIC EVENTS INVOLVED IN EARLY PHASES OF COLORECTAL TUMORIGENESIS. FINALLY, WE CARRIED OUT A CRITICAL REVIEW OF THE LITERATURE ON OFF-TARGET MECHANISMS OF ASPIRIN ACTION AS ANTICANCER DRUG. 2015 6 4732 44 NOVEL BIOMARKERS FOR INFLAMMATORY BOWEL DISEASE AND COLORECTAL CANCER: AN INTERPLAY BETWEEN METABOLIC DYSREGULATION AND EXCESSIVE INFLAMMATION. PERSISTENT INFLAMMATION CAN TRIGGER ALTERED EPIGENETIC, INFLAMMATORY, AND BIOENERGETIC STATES. INFLAMMATORY BOWEL DISEASE (IBD) IS AN IDIOPATHIC DISEASE CHARACTERIZED BY CHRONIC INFLAMMATION OF THE GASTROINTESTINAL TRACT, WITH EVIDENCE OF SUBSEQUENT METABOLIC SYNDROME DISORDER. STUDIES HAVE DEMONSTRATED THAT AS MANY AS 42% OF PATIENTS WITH ULCERATIVE COLITIS (UC) WHO ARE FOUND TO HAVE HIGH-GRADE DYSPLASIA, EITHER ALREADY HAD COLORECTAL CANCER (CRC) OR DEVELOP IT WITHIN A SHORT TIME. THE PRESENCE OF LOW-GRADE DYSPLASIA IS ALSO PREDICTIVE OF CRC. MANY SIGNALING PATHWAYS ARE SHARED AMONG IBD AND CRC, INCLUDING CELL SURVIVAL, CELL PROLIFERATION, ANGIOGENESIS, AND INFLAMMATORY SIGNALING PATHWAYS. CURRENT IBD THERAPEUTICS TARGET A SMALL SUBSET OF MOLECULAR DRIVERS OF IBD, WITH MANY FOCUSED ON THE INFLAMMATORY ASPECT OF THE PATHWAYS. THUS, THERE IS A GREAT NEED TO IDENTIFY BIOMARKERS OF BOTH IBD AND CRC, THAT CAN BE PREDICTIVE OF THERAPEUTIC EFFICACY, DISEASE SEVERITY, AND PREDISPOSITION TO CRC. IN THIS STUDY, WE EXPLORED THE CHANGES IN BIOMARKERS SPECIFIC FOR INFLAMMATORY, METABOLIC, AND PROLIFERATIVE PATHWAYS, TO HELP DETERMINE THE RELEVANCE TO BOTH IBD AND CRC. OUR ANALYSIS DEMONSTRATED, FOR THE FIRST TIME IN IBD, THE LOSS OF THE TUMOR SUPPRESSOR PROTEIN RAS ASSOCIATED FAMILY PROTEIN 1A (RASSF1A), VIA EPIGENETIC CHANGES, THE HYPERACTIVATION OF THE OBLIGATE KINASE OF THE NOD2 PATHOGEN RECOGNITION RECEPTOR (RECEPTOR INTERACTING PROTEIN KINASE 2 [RIPK2]), THE LOSS OF ACTIVATION OF THE METABOLIC KINASE, AMP ACTIVATED PROTEIN KINASE (AMPKALPHA1), AND, LASTLY, THE ACTIVATION OF THE TRANSCRIPTION FACTOR AND KINASE YES ASSOCIATED PROTEIN (YAP) KINASE, THAT IS INVOLVED IN PROLIFERATION OF CELLS. THE EXPRESSION AND ACTIVATION STATUS OF THESE FOUR ELEMENTS ARE MIRRORED IN IBD, CRC, AND IBD-CRC PATIENTS AND, IMPORTANTLY, IN MATCHED BLOOD AND BIOPSY SAMPLES. THE LATTER WOULD SUGGEST THAT BIOMARKER ANALYSIS CAN BE PERFORMED NON-INVASIVELY, TO UNDERSTAND IBD AND CRC, WITHOUT THE NEED FOR INVASIVE AND COSTLY ENDOSCOPIC ANALYSIS. THIS STUDY, FOR THE FIRST TIME, ILLUSTRATES THE NEED TO UNDERSTAND IBD OR CRC BEYOND AN INFLAMMATORY PERSPECTIVE AND THE VALUE OF THERAPEUTICS DIRECTED TO RESET ALTERED PROLIFERATIVE AND METABOLIC STATES WITHIN THE COLON. THE USE OF SUCH THERAPEUTICS MAY TRULY DRIVE PATIENTS INTO REMISSION. 2023 7 4283 30 MICRORNA BIOMARKERS IN IBD-DIFFERENTIAL DIAGNOSIS AND PREDICTION OF COLITIS-ASSOCIATED CANCER. INFLAMMATORY BOWEL DISEASE (IBD) INCLUDES CROHN'S DISEASE (CD) AND ULCERATIVE COLITIS (UC). THESE ARE CHRONIC AUTOIMMUNE DISEASES OF UNKNOWN ETIOLOGY AFFECTING THE GASTROINTESTINAL TRACT. THE IBD POPULATION INCLUDES A HETEROGENEOUS GROUP OF PATIENTS WITH VARYING DISEASE COURSES REQUIRING PERSONALIZED TREATMENT PROTOCOLS. THE COMPLEXITY OF THE DISEASE OFTEN DELAYS THE DIAGNOSIS AND THE INITIATION OF APPROPRIATE TREATMENTS. IN A SUBSET OF PATIENTS, IBD LEADS TO COLITIS-ASSOCIATED CANCER (CAC). MICRORNAS ARE SINGLE-STRANDED REGULATORY NONCODING RNAS OF 18 TO 22 NUCLEOTIDES WITH PUTATIVE ROLES IN THE PATHOGENESIS OF IBD AND COLORECTAL CANCER. THEY HAVE BEEN EXPLORED AS BIOMARKERS AND THERAPEUTIC TARGETS. BOTH TISSUE-DERIVED AND CIRCULATING MICRORNAS HAVE EMERGED AS PROMISING BIOMARKERS IN THE DIFFERENTIAL DIAGNOSIS AND IN THE PROGNOSIS OF DISEASE SEVERITY OF IBD AS WELL AS PREDICTIVE BIOMARKERS IN DRUG RESISTANCE. IN ADDITION, KNOWLEDGE OF THE CELLULAR LOCALIZATION OF DIFFERENTIALLY EXPRESSED MICRORNAS IS A PREREQUISITE FOR DECIPHERING THE BIOLOGICAL ROLE OF THESE IMPORTANT EPIGENETIC REGULATORS AND THE CELLULAR LOCALIZATION MAY EVEN CONTRIBUTE TO AN ALTERNATIVE REPERTOIRE OF BIOMARKERS. IN THIS REVIEW, WE DISCUSS FINDINGS BASED ON RT-QPCR, MICROARRAY PROFILING, NEXT GENERATION SEQUENCING AND IN SITU HYBRIDIZATION OF MICRORNA BIOMARKERS IDENTIFIED IN THE CIRCULATION AND IN TISSUE BIOPSIES. 2020 8 4539 26 MULTISTAGE CARCINOGENESIS IN MOUSE SKIN. THE MOUSE SKIN MODEL OF MULTISTAGE CARCINOGENESIS HAS FOR MANY YEARS PROVIDED A CONCEPTUAL FRAMEWORK FOR STUDYING CARCINOGENESIS MECHANISMS AND POTENTIAL MEANS FOR INHIBITING SPECIFIC STAGES OF CARCINOGENESIS. THE PROCESS OF SKIN CARCINOGENESIS INVOLVES THE STEPWISE ACCUMULATION OF GENETIC CHANGE ULTIMATELY LEADING TO MALIGNANCY. INITIATION, THE FIRST STEP IN MULTISTAGE SKIN CARCINOGENESIS INVOLVES CARCINOGEN-INDUCED GENETIC CHANGES. A TARGET GENE IDENTIFIED FOR SOME SKIN TUMOR INITIATORS IS C-HA-RAS. THE SECOND STEP, THE PROMOTION STAGE, INVOLVES PROCESSES WHEREBY INITIATED CELLS UNDERGO SELECTIVE CLONAL EXPANSION TO FORM VISIBLE PREMALIGNANT LESIONS TERMED PAPILLOMAS. THE PROCESS OF TUMOR PROMOTION INVOLVES THE PRODUCTION AND MAINTENANCE OF A SPECIFIC AND CHRONIC HYPERPLASIA CHARACTERIZED BY A SUSTAINED CELLULAR PROLIFERATION OF EPIDERMAL CELLS. THESE CHANGES ARE BELIEVED TO RESULT FROM EPIGENETIC MECHANISMS SUCH AS ACTIVATION OF THE CELLULAR RECEPTOR, PROTEIN KINASE C, BY SOME CLASSES OF TUMOR PROMOTERS. THE PROGRESSION STAGE INVOLVES THE CONVERSION OF PAPILLOMAS TO MALIGNANT TUMORS, SQUAMOUS CELL CARCINOMAS. THE ACCUMULATION OF ADDITIONAL GENETIC CHANGES IN CELLS COMPRISING PAPILLOMAS HAS BEEN CORRELATED WITH TUMOR PROGRESSION, INCLUDING TRISOMIES OF CHROMOSOMES 6 AND 7 AND LOSS OF HETEROZYGOSITY. THE CURRENT REVIEW FOCUSES ON THE MECHANISMS INVOLVED IN MULTISTAGE SKIN CARCINOGENESIS, A SUMMARY OF KNOWN INHIBITORS OF SPECIFIC STAGES AND THEIR PROPOSED MECHANISMS OF ACTION, AND THE RELEVANCE OF THIS MODEL SYSTEM TO HUMAN CANCER. 1992 9 4438 33 MOLECULAR FINDINGS IN BARRETT'S EPITHELIUM. BARRETT'S METAPLASIA IS A PREMALIGNANT CONDITION AND REMAINS THE NUMBER ONE RISK FACTOR FOR DEVELOPING ADENOCARCINOMA. THE HISTOLOGIC CHANGES LEADING TO ADENOCARCINOMA ARE ACCOMPANIED BY GENETIC DISTURBANCES OF THE EPITHELIAL CELLS ITSELF AS WELL AS THE SURROUNDING STROMA. GENETIC AND EPIGENETIC EVENTS AFFECT THE CELL CYCLE, LEADING TO GROWTH SELF-SUFFICIENCY AND IGNORATION OF ANTIGROWTH SIGNALS. THE BALANCE OF CELL TURNOVER IS INSTABLE BY AVOIDANCE OF APOPTOSIS AND A GENERAL LIMITLESS OF THE REPLICATIVE POTENTIAL OF THE (MUTATED) STEM CELLS. SUSTAINED ANGIOGENESIS, NOT ONLY A CONSEQUENCE OF CHRONIC INFLAMMATION, MAY PRECEDE INVASION OF GENETICALLY INSTABLE (ANEUPLOID) CELLS. THE PRINCIPAL GENETIC CHANGES IN BARRETT'S CARCINOGENESIS ARE COMPARABLE TO THOSE KNOWN FROM OTHER EPITHELIAL MALIGNANCIES. LOSS OF P16 GENE EXPRESSION (BY DELETION OR HYPERMETHYLATION), THE LOSS OF P53 EXPRESSION (BY MUTATION AND DELETION), THE INCREASE IN CYCLIN EXPRESSION, AND THE LOSSES OF RB, APC AS WELL AS VARIOUS CHROMOSOMAL LOCI HAVE BEEN REPORTED. SINCE THESE GENETIC OR EPIGENETIC ALTERATIONS ARE NEITHER TUMOR NOR STAGE SPECIFIC, THEY COULD NOT GAIN DIAGNOSTIC SIGNIFICANCE AS BIOMARKERS UNTIL NOW. 2004 10 45 24 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 11 2483 34 EPIGENETIC VARIATION AND HUMAN DISEASE. CYTOSINE GUANINE DINUCLEOTIDE (CPG) ISLAND METHYLATION IS A KNOWN MECHANISM OF EPIGENETIC INHERITANCE IN POSTMEIOTIC CELLS. THROUGH ASSOCIATED CHROMATIN CHANGES AND SILENCING, SUCH EPIGENETIC STATES CAN INFLUENCE CELLULAR PHYSIOLOGY AND AFFECT DISEASE RISK AND SEVERITY. OUR STUDIES OF CPG ISLAND METHYLATION IN NORMAL COLORECTAL MUCOSA REVEALED PROGRESSIVE AGE-RELATED INCREASES AT MULTIPLE GENE LOCI, SUGGESTING GENOME-WIDE MOLECULAR ALTERATIONS WITH POTENTIAL TO SILENCE GENE EXPRESSION. HOWEVER, THERE WAS CONSIDERABLE VARIATION IN THE DEGREE OF METHYLATION AMONG INDIVIDUALS OF COMPARABLE AGES. SUCH VARIATION COULD BE RELATED TO GENETIC FACTORS, LIFESTYLE, OR ENVIRONMENTAL EXPOSURES. STUDIES IN ULCERATIVE COLITIS AND HEPATOCELLULAR CIRRHOSIS AND NEOPLASIA REVEALED THAT CHRONIC INFLAMMATORY STATES ARE ACCOMPANIED BY MARKED INCREASES IN CPG ISLAND METHYLATION IN NORMAL-APPEARING TISSUES, CONFIRMING THE HYPOTHESIS THAT PROINFLAMMATORY EXPOSURES COULD ACCOUNT FOR PART OF THE EPIGENETIC VARIATION IN HUMAN POPULATIONS. PRELIMINARY DATA ALSO SUGGEST POTENTIAL INFLUENCES OF LIFESTYLE AND EXPOSURE FACTORS ON CPG ISLAND METHYLATION. IT IS SUGGESTED THAT EPIGENETIC VARIATION RELATED TO AGING, LIFESTYLE, EXPOSURES AND POSSIBLY GENETIC FACTORS, IS ONE OF THE MODULATORS OF ACQUIRED, AGE-RELATED HUMAN DISEASES, INCLUDING NEOPLASIA. 2002 12 1180 38 CONVERGENCE OF GENETIC, NUTRITIONAL AND INFLAMMATORY FACTORS IN GASTROINTESTINAL CANCERS. GASTROINTESTINAL CANCERS ACCOUNT FOR 20% OF ALL CANCER INCIDENCES WORLDWIDE. COLORECTAL CANCER IS THE SECOND MOST COMMON CAUSE OF ALL CANCER-RELATED MORTALITY AND IS INCREASING IN WESTERN SOCIETIES. INFECTION AND INFLAMMATION CONTRIBUTE TO 15-20% OF ALL MALIGNANCIES, AND ARE PREDISPOSING RISK FACTORS FOR GASTROINTESTINAL CANCERS. HELICOBACTER PYLORI INFECTION IS COMMONLY ASSOCIATED WITH GASTRIC CANCERS, AND CHRONIC INFLAMMATION INCREASES THE RISK OF COLORECTAL CANCER BY 1% PER YEAR. MICRONUTRIENT STATUS AND COMMON GENETIC VARIATIONS IN HUMAN POPULATIONS MODIFY RISK FOR GASTROINTESTINAL CANCER. CHRONIC INFLAMMATION PROMOTES CARCINOGENESIS BY INDUCING GENE MUTATIONS, INHIBITING APOPTOSIS, AND STIMULATING ANGIOGENESIS AND CELL PROLIFERATION. INFLAMMATION ALSO INDUCES EPIGENETIC ALTERATIONS THAT ARE ASSOCIATED WITH CANCER DEVELOPMENT. TWO KEY GENES IN THE INFLAMMATORY PROCESS, CYCLOOXYGENASE-2 (COX-2) AND NUCLEAR FACTOR-KAPPA B (NF-KAPPAB), PROVIDE A MECHANISTIC LINK BETWEEN INFLAMMATION AND CANCER AND ARE TARGETS FOR CHEMOPREVENTION. DIETARY COMPONENTS, AND HUMAN GENETIC VARIATION THAT AFFECTS NUTRIENT UTILIZATION, CAN DIRECTLY MODIFY INFLAMMATORY PROCESSES AND/OR SUPPRESS GENOMIC ALTERATIONS THAT ARE THE MOLECULAR ANTECEDENTS OF CANCERS. THE PRESENT REPORT FOCUSES ON THE CONVERGENCE OF GENETIC, NUTRITIONAL, AND INFLAMMATORY FACTORS IN THE INITIATION AND PROGRESSION OF GASTROINTESTINAL CANCERS, AND THE EMERGING DIETARY STRATEGIES FOR CANCER PREVENTION. 2007 13 4479 34 MOLECULAR PATHOGENESIS OF ORAL SQUAMOUS CELL CARCINOMA: IMPLICATIONS FOR THERAPY. THE DEVELOPMENT OF ORAL SQUAMOUS CELL CARCINOMA (OSCC) IS A MULTISTEP PROCESS REQUIRING THE ACCUMULATION OF MULTIPLE GENETIC ALTERATIONS, INFLUENCED BY A PATIENT'S GENETIC PREDISPOSITION AS WELL AS BY ENVIRONMENTAL INFLUENCES, INCLUDING TOBACCO, ALCOHOL, CHRONIC INFLAMMATION, AND VIRAL INFECTION. TUMORIGENIC GENETIC ALTERATIONS CONSIST OF TWO MAJOR TYPES: TUMOR SUPPRESSOR GENES, WHICH PROMOTE TUMOR DEVELOPMENT WHEN INACTIVATED; AND ONCOGENES, WHICH PROMOTE TUMOR DEVELOPMENT WHEN ACTIVATED. TUMOR SUPPRESSOR GENES CAN BE INACTIVATED THROUGH GENETIC EVENTS SUCH AS MUTATION, LOSS OF HETEROZYGOSITY, OR DELETION, OR BY EPIGENETIC MODIFICATIONS SUCH AS DNA METHYLATION OR CHROMATIN REMODELING. ONCOGENES CAN BE ACTIVATED THROUGH OVEREXPRESSION DUE TO GENE AMPLIFICATION, INCREASED TRANSCRIPTION, OR CHANGES IN STRUCTURE DUE TO MUTATIONS THAT LEAD TO INCREASED TRANSFORMING ACTIVITY. THIS REVIEW FOCUSES ON THE MOLECULAR MECHANISMS OF ORAL CARCINOGENESIS AND THE USE OF BIOLOGIC THERAPY TO SPECIFICALLY TARGET MOLECULES ALTERED IN OSCC. THE RAPID PROGRESS THAT HAS BEEN MADE IN OUR UNDERSTANDING OF THE MOLECULAR ALTERATIONS CONTRIBUTING TO THE DEVELOPMENT OF OSCC IS LEADING TO IMPROVEMENTS IN THE EARLY DIAGNOSIS OF TUMORS AND THE REFINEMENT OF BIOLOGIC TREATMENTS INDIVIDUALIZED TO THE SPECIFIC CHARACTERISTICS OF A PATIENT'S TUMOR. 2008 14 3681 39 INFLAMMATION, DNA METHYLATION AND COLITIS-ASSOCIATED CANCER. INFLAMMATION CAN RESULT FROM A RANGE OF SOURCES INCLUDING MICROBIAL INFECTIONS, EXPOSURE TO ALLERGENS AND TOXIC CHEMICALS, AUTOIMMUNE DISEASE AND OBESITY. A WELL-BALANCED IMMUNE RESPONSE CAN BE ANTI-TUMORIGENIC; HOWEVER, A SUSTAINED OR CHRONIC INFLAMMATORY RESPONSE IS GENERALLY HARMFUL AS THE IMMUNE RESPONSE BECOMES DISTORTED. A CAUSAL LINK BETWEEN CHRONIC INFLAMMATION AND CANCER IS NOW WELL ACCEPTED AND MANY CHRONICALLY INFLAMED ORGANS OF THE GASTROINTESTINAL TRACT SHOW THIS ASSOCIATION. FOR EXAMPLE, PATIENTS WITH INFLAMMATORY BOWEL DISEASE (IBD), INCLUDING BOTH ULCERATIVE COLITIS AND CROHN'S DISEASE, HAVE A 2- TO 3-FOLD GREATER LIFETIME RISK OF DEVELOPING COLORECTAL CANCER COMPARED WITH THE GENERAL POPULATION. THE DEVELOPMENT OF COLITIS-ASSOCIATED CANCER (CAC) IS THOUGHT TO BE MULTIFACETED AND IS PROBABLY DUE TO A COMBINATION OF GENETIC FACTORS, EPIGENETIC FACTORS AND THE DURATION, EXTENT AND SEVERITY OF DISEASE. RECENTLY, EPIGENETIC ALTERATIONS, IN PARTICULAR ALTERATIONS IN DNA METHYLATION, HAVE BEEN OBSERVED DURING INFLAMMATION AND INFLAMMATION-ASSOCIATED CARCINOGENESIS. THE MEDIATORS OF THIS, THE SIGNIFICANCE OF THESE CHANGES IN DNA METHYLATION AND THE EFFECT THIS HAS ON GENE EXPRESSION AND THE MALIGNANT TRANSFORMATION OF THE EPITHELIAL CELLS DURING IBD AND CAC ARE DISCUSSED IN THIS REVIEW. THE RECENT ADVANCES IN TECHNOLOGIES TO STUDY GENOME-WIDE DNA METHYLATION AND THE THERAPEUTIC POTENTIAL OF UNDERSTANDING THESE MOLECULAR MECHANISMS ARE ALSO HIGHLIGHTED. 2012 15 5291 33 PROSTATE CARCINOGENESIS: INSIGHTS IN RELATION TO EPIGENETICS AND INFLAMMATION. PROSTATE CANCER IS A MULTIFACTORIAL DISEASE THAT MAINLY OCCURS DUE TO THE ACCUMULATION OF SOMATIC, GENETIC, AND EPIGENETIC CHANGES, RESULTING IN THE INACTIVATION OF TUMOR-SUPPRESSOR GENES AND ACTIVATION OF ONCOGENES. MUTATIONS IN GENES, SPECIFICALLY THOSE THAT CONTROL CELL GROWTH AND DIVISION OR THE REPAIR OF DAMAGED DNA, MAKE THE CELLS GROW AND DIVIDE UNCONTROLLABLY TO FORM A TUMOR. THE RISK OF DEVELOPING PROSTATE CANCER DEPENDS UPON THE GENE THAT HAS UNDERGONE THE MUTATION. IDENTIFYING SUCH GENETIC RISK FACTORS FOR PROSTATE CANCER POSES A CHALLENGE FOR THE RESEARCHERS. BESIDES GENETIC MUTATIONS, MANY EPIGENETIC ALTERATIONS, INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS (METHYLATION, ACETYLATION, UBIQUITYLATION, SUMOYLATION, AND PHOSPHORYLATION) NUCLEOSOMAL REMODELING, AND CHROMOSOMAL LOOPING, HAVE SIGNIFICANTLY CONTRIBUTED TO THE ONSET OF PROSTATE CANCER AS WELL AS THE PROGNOSIS, DIAGNOSIS, AND TREATMENT OF PROSTATE CANCER. CHRONIC INFLAMMATION ALSO PLAYS A MAJOR ROLE IN THE ONSET AND PROGRESSION OF HUMAN CANCER, VIA MODIFICATIONS IN THE TUMOR MICROENVIRONMENT BY INITIATING EPITHELIALMESENCHYMAL TRANSITION AND REMODELING THE EXTRACELLULAR MATRIX. IN THIS ARTICLE, THE AUTHORS PRESENT A BRIEF HISTORY OF THE MECHANISMS AND POTENTIAL LINKS BETWEEN THE GENETIC ABERRATIONS, EPIGENETIC CHANGES, INFLAMMATION, AND INFLAMMASOMES THAT ARE KNOWN TO CONTRIBUTE TO THE PROGNOSIS OF PROSTATE CANCER. FURTHERMORE, THE AUTHORS EXAMINE AND DISCUSS THE CLINICAL POTENTIAL OF PROSTATE CARCINOGENESIS IN RELATION TO EPIGENETICS AND INFLAMMATION FOR ITS DIAGNOSIS AND TREATMENT.. 2021 16 4733 28 NOVEL BIOMARKERS FOR THE IDENTIFICATION AND TARGETED THERAPY OF GASTRIC CANCER. GASTRIC CANCER DEVELOPMENT FOLLOWS THE PATHOLOGIC PATTERN SUCH THAT CHRONIC INFLAMMATION IN THE GASTRIC MUCOSA PROGRESSIVELY TRANSFORMS NORMAL MUCOSA INTO ATROPHY, INTESTINAL METAPLASIA, ADENOMA/DYSPLASIA AND EVENTUALLY INVASIVE AND METASTATIC TUMORS. THE ACCUMULATION OF MULTIPLE GENETIC AND EPIGENETIC ALTERATIONS LEADS TO THE DYSREGULATION OF ONCOGENES AND TUMOR SUPPRESSORS, WHICH WAS CONSIDERED AS THE DRIVER BEHIND EVENTS DURING THE TUMORIGENESIS. ALMOST ALL GASTRIC CANCERS ARE ADENOCARCINOMAS, WHICH SHARE CONSIDERABLE HETEROGENEITY WITH DISTINCT MORPHOLOGY, PATHOGENESIS AND CLINICAL BEHAVIOR. THEREFORE, IDENTIFYING SUBTYPES OF GASTRIC CANCERS WITH MOLECULAR AND GENETIC FEATURES WILL BE BENEFICIAL FOR THE EARLY IDENTIFICATION AND SELECTION OF NEW EFFECTIVE AGENTS FOR TARGETED TREATMENT. HIGH-THROUGHPUT SEQUENCING TECHNIQUES SUCH AS WHOLE GENOMIC, EPIGENOME AND TRANSCRIPTOME SEQUENCING AND PROTEOMICS PLATFORMS HAVE IDENTIFIED MAJOR GENOMIC CHARACTERISTICS THAT EXHIBIT IDENTIFICATION AND PROGNOSTIC IMPACTS AND DISTINCT RESPONSE PATTERNS. IN THIS ARTICLE, THE AUTHORS AIM TO SUMMARIZE THE INFORMATION REGARDING THE MOST PROMISING MOLECULES THAT MAY HAVE CLINICAL APPLICATION AS NON-INVASIVE BIOMARKERS AND THERAPY TARGETS. 2015 17 2970 40 GENETIC AND EPIGENETIC SIGNATURES IN HUMAN HEPATOCELLULAR CARCINOMA: A SYSTEMATIC REVIEW. HEPATOCELLULAR CARCINOMA (HCC) IS THE THIRD MOST COMMON CAUSE OF CANCER DEATHS WORLDWIDE, AND THE INCIDENCE OF THIS FATAL DISEASE IS STILL ON RISE. THE MAJORITY OF HCCS EMERGE IN THE BACKGROUND OF A CHRONIC LIVER DISEASE, SUCH AS CHRONIC HEPATITIS AND LIVER CIRRHOSIS. THE CURRENT UNDERSTANDING IS THAT MAJORITY OF HCCS EVOLVE AS A CONSEQUENCE OF CHRONIC INFLAMMATION AND DUE TO THE PRESENCE OF INFECTION WITH HEPATITIS VIRUSES. THESE UNDERLYING PATHOGENIC STIMULI SUBSEQUENTLY INDUCE A SPECTRUM OF GENETIC AND EPIGENETIC ALTERATIONS IN SEVERAL CANCER-RELATED GENES, WHICH ARE INVOLVED IN CELL-CYCLE REGULATION, CELL GROWTH AND ADHESION. SUCH WIDESPREAD GENOMIC ALTERATIONS CAUSE DISRUPTION OF NORMAL CELLULAR SIGNALING AND FINALLY LEAD TO THE ACQUISITION OF A MALIGNANT PHENOTYPE IN HCC. IN GENERAL, THE TYPE OF GENE ALTERATIONS, SUCH AS POINT MUTATIONS, DELETION OF CHROMOSOMAL REGIONS AND ABNORMAL METHYLATION OF GENE PROMOTERS DIFFER ACCORDING TO THE INDIVIDUAL TARGETED GENE. IN HCC, INCIDENCE OF GENETIC ALTERATIONS IS RELATIVELY RARE AND IS LIMITED TO A SUBSET OF FEW CANCER-SPECIFIC GENES, SUCH AS THE TUMOR SUPPRESSOR P53, RB GENES AND ONCOGENES SUCH AS THE CTNNB1. IN CONTRAST, EPIGENETIC CHANGES THAT INVOLVE ABERRANT METHYLATION OF GENES AND OTHER POST-TRANSCRIPTIONAL HISTONE MODIFICATIONS OCCUR FAR MORE FREQUENTLY, AND SOME OF THESE EPIGENETIC ALTERATIONS ARE NOW BEING EXPLOITED FOR THE DEVELOPMENT OF MOLECULAR DIAGNOSTIC SIGNATURES FOR HCC. IN ADDITION, RECENT FINDINGS OF UNIQUE MICRORNA EXPRESSION PROFILES ALSO PROVIDE AN EVIDENCE FOR THE EXISTENCE OF NOVEL MECHANISMS FOR GENE EXPRESSION REGULATION IN HCC. IN THIS REVIEW ARTICLE, WE WILL REVIEW THE CURRENT STATE OF KNOWLEDGE ON THE ACTIVATION OF VARIOUS ONCOGENIC PATHWAYS AND THE INACTIVATION OF TUMOR SUPPRESSOR PATHWAYS IN HCC THAT RESULT IN THE DISRUPTION OF CANCER-RELATED GENE FUNCTION. IN ADDITION, WE WILL SPECIFICALLY EMPHASIZE THE CLINICAL IMPLICATION OF SOME OF THESE GENETIC AND EPIGENETIC ALTERATIONS IN THE MANAGEMENT OF HEPATOCARCINOGENESIS. 2011 18 4888 34 OXIDATIVE DAMAGE IN THE PROGRESSION OF CHRONIC LIVER DISEASE TO HEPATOCELLULAR CARCINOMA: AN INTRICATE PATHWAY. THE HISTO-PATHOLOGIC AND MOLECULAR MECHANISMS LEADING TO INITIATION AND PROGRESSION OF HEPATOCELLULAR CARCINOMA (HCC) ARE STILL ILL-DEFINED; HOWEVER, THERE IS INCREASING EVIDENCE THAT THE GRADUAL ACCUMULATION OF MUTATIONS, GENETIC AND EPIGENETIC CHANGES WHICH OCCUR IN PRENEOPLASTIC HEPATOCYTES RESULTS IN THE DEVELOPMENT OF DYSPLASTIC FOCI, NODULES, AND FINALLY, OVERT HCC. AS WELL AS MANY OTHER NEOPLASIAS, LIVER CANCER IS CONSIDERED AN "INFLAMMATORY CANCER", ARISING FROM A CONTEXT OF INFLAMMATION, AND CHARACTERIZED BY INFLAMMATION-RELATED MECHANISMS THAT FAVOR TUMOR CELL SURVIVAL, PROLIFERATION, AND INVASION. MOLECULAR MECHANISMS THAT LINK INFLAMMATION AND NEOPLASIA HAVE BEEN WIDELY INVESTIGATED, AND IT HAS BEEN WELL ESTABLISHED THAT INFLAMMATORY CELLS RECRUITED AT THESE SITES WITH ONGOING INFLAMMATORY ACTIVITY RELEASE CHEMOKINES THAT ENHANCE THE PRODUCTION OF REACTIVE OXYGEN SPECIES. THE LATTER, IN TURN, PROBABLY HAVE A MAJOR PATHOGENIC ROLE IN THE CONTINUUM STARTING FROM HEPATITIS FOLLOWED BY CHRONIC INFLAMMATION, AND ULTIMATELY LEADING TO CANCER. THE RELATIONSHIP AMONGST CHRONIC LIVER INJURY, FREE RADICAL PRODUCTION, AND DEVELOPMENT OF HCC IS EXPLORED IN THE PRESENT REVIEW, PARTICULARLY IN THE LIGHT OF THE COMPLEX NETWORK THAT INVOLVES OXIDATIVE DNA DAMAGE, CYTOKINE SYNTHESIS, TELOMERE DYSFUNCTION, AND MICRORNA REGULATION. 2014 19 2033 35 EPIGENETIC CHANGES IN SOLID AND HEMATOPOIETIC TUMORS. THERE ARE THREE CONNECTED MOLECULAR MECHANISMS OF EPIGENETIC CELLULAR MEMORY IN MAMMALIAN CELLS: DNA METHYLATION, HISTONE MODIFICATIONS, AND RNA INTERFERENCE. THE FIRST TWO HAVE NOW BEEN FIRMLY LINKED TO NEOPLASTIC TRANSFORMATION. HYPERMETHYLATION OF CPG-RICH PROMOTERS TRIGGERS LOCAL HISTONE CODE MODIFICATIONS RESULTING IN A CELLULAR CAMOUFLAGE MECHANISM THAT SEQUESTERS GENE PROMOTERS AWAY FROM TRANSCRIPTION FACTORS AND RESULTS IN STABLE SILENCING. THIS NORMALLY RESTRICTED MECHANISM IS UBIQUITOUSLY USED IN CANCER TO SILENCE HUNDREDS OF GENES, AMONG WHICH SOME CRITICALLY CONTRIBUTE TO THE NEOPLASTIC PHENOTYPE. VIRTUALLY EVERY PATHWAY IMPORTANT TO CANCER FORMATION IS AFFECTED BY THIS PROCESS. METHYLATION PROFILING OF HUMAN CANCERS REVEALS TISSUE-SPECIFIC EPIGENETIC SIGNATURES, AS WELL AS TUMOR-SPECIFIC SIGNATURES, REFLECTING IN PARTICULAR THE PRESENCE OF EPIGENETIC INSTABILITY IN A SUBSET OF CANCERS AFFECTED BY THE CPG ISLAND METHYLATOR PHENOTYPE. GENERALLY, METHYLATION PATTERNS CAN BE TRACED TO A TISSUE-SPECIFIC, PROLIFERATION-DEPENDENT ACCUMULATION OF ABERRANT PROMOTER METHYLATION IN AGING TISSUES, A PROCESS THAT CAN BE ACCELERATED BY CHRONIC INFLAMMATION AND LESS WELL-DEFINED MECHANISMS INCLUDING, POSSIBLY, DIET AND GENETIC PREDISPOSITION. THE EPIGENETIC MACHINERY CAN ALSO BE ALTERED IN CANCER BY SPECIFIC LESIONS IN EPIGENETIC EFFECTOR GENES, OR BY ABERRANT RECRUITMENT OF THESE GENES BY MUTANT TRANSCRIPTION FACTORS AND COACTIVATORS. EPIGENETIC PATTERNS ARE PROVING CLINICALLY USEFUL IN HUMAN ONCOLOGY VIA RISK ASSESSMENT, EARLY DETECTION, AND PROGNOSTIC CLASSIFICATION. PHARMACOLOGIC MANIPULATION OF THESE PATTERNS-EPIGENETIC THERAPY-IS ALSO POISED TO CHANGE THE WAY WE TREAT CANCER IN THE CLINIC. 2005 20 1912 39 ENVIRONMENT, DIET AND CPG ISLAND METHYLATION: EPIGENETIC SIGNALS IN GASTROINTESTINAL NEOPLASIA. THE EPITHELIAL SURFACES OF THE MAMMALIAN ALIMENTARY TRACT ARE CHARACTERISED BY VERY HIGH RATES OF CELL PROLIFERATION AND DNA SYNTHESIS, AND IN HUMANS THEY ARE HIGHLY SUSCEPTIBLE TO CANCER. THE ROLE OF SOMATIC MUTATIONS AS DRIVERS OF CARCINOGENESIS IN THE ALIMENTARY TRACT IS WELL ESTABLISHED, BUT THE IMPORTANCE OF GENE SILENCING BY EPIGENETIC MECHANISMS IS INCREASINGLY RECOGNISED. METHYLATION OF CPG ISLANDS IS AN IMPORTANT COMPONENT OF THE EPIGENETIC CODE THAT REGULATES GENE EXPRESSION DURING DEVELOPMENT AND NORMAL CELLULAR DIFFERENTIATION, AND A NUMBER OF GENES ARE WELL KNOWN TO BECOME ABNORMALLY METHYLATED DURING THE DEVELOPMENT OF TUMOURS OF THE OESOPHAGUS, STOMACH AND COLORECTUM. ABERRANT PATTERNS OF DNA METHYLATION DEVELOP AS A RESULT OF PATHOLOGICAL PROCESSES SUCH AS CHRONIC INFLAMMATION, AND IN RESPONSE TO VARIOUS DIETARY FACTORS, INCLUDING IMBALANCES IN THE SUPPLY OF METHYL DONORS, PARTICULARLY FOLATES, AND EXPOSURE TO DNA METHYLTRANSFERASE INHIBITORS, WHICH INCLUDE POLYPHENOLS AND POSSIBLY ISOTHIOCYANATES FROM PLANT FOODS. HOWEVER THE IMPORTANCE OF THESE ENVIRONMENTAL INTERACTIONS IN HUMAN HEALTH AND DISEASE REMAINS TO BE ESTABLISHED. RECENT MOVES TO MODIFY THE EXPOSURE OF HUMAN POPULATIONS TO FOLATE, BY MANDATORY SUPPLEMENTATION OF CEREAL FOODS, EMPHASISE THE IMPORTANCE OF UNDERSTANDING THE SUSCEPTIBILITY OF THE HUMAN EPIGENOME TO DIETARY AND OTHER ENVIRONMENTAL EFFECTS. 2008