1 1502 120 DNA METHYLATION AND EPIGENETIC EVENTS UNDERLYING RENAL CELL CARCINOMAS. RENAL CELL CARCINOMA (RCC) REFERS TO A GROUP OF TUMORS THAT DEVELOP FROM THE EPITHELIUM OF THE KIDNEY TUBES, INCLUDING CLEAR CELL RCC, PAPILLARY RCC, AND CHROMOPHOBE RCC. MOST CLEAR CELL RENAL CARCINOMAS HAVE A LARGE HISTOLOGIC SUBTYPE, GENETIC OR EPIGENETIC VON HIPPEL-LINDAU (VHL). A COMPREHENSIVE ANALYSIS OF THE GENETIC MODIFICATION GENOME SUGGESTED THAT CHROMOSOME 3P LOSS AND CHROMOSOME GAINS 5Q AND 7 MAY BE SIGNIFICANT COPY DEFECTS IN THE DEVELOPMENT OF CLEAR RCC. A MORE POTENT RCC MAY DEVELOP IF CHROMOSOME 1P, 4, 9, 13Q, OR 14Q IS ALSO LOST. RENAL CARCINOGENESIS IS NOT ASSOCIATED WITH CHRONIC INFLAMMATION OR HISTOLOGICAL CHANGES. HOWEVER, IF REGIONAL HYPERMETHYLATION OF DNA IN CPG C-TYPE ISLANDS HAS ALREADY ACCUMULATED IN CANCER-FREE KIDNEY TISSUE, IT IMPLIES THAT THE PRESENCE OF MALIGNANT KIDNEY LESIONS MAY ALSO BE DETECTED BY MODIFIED DNA METHYLATION. MODIFICATION OF DNA METHYLATION IN CANCEROUS KIDNEY TISSUE MAY ADVANCE KIDNEY TISSUE TO EPIGENETIC MUTATIONS AND GENES, LEADING TO MORE SERIOUS CANCERS AND EVEN DETERMINING A PATIENT'S OUTCOME. THE GENETIC AND EPIGENETIC PROFILE PROVIDES ACCURATE PREDICTORS FOR PATIENTS WITH KIDNEY CANCER. NEW GENETIC AND EPIGENETIC ANALYSIS TECHNOLOGIES WILL HELP TO SPEED UP THE IDENTIFICATION OF VITAL CELLS FOR KIDNEY CANCER PREVENTION, DIAGNOSIS, AND TREATMENT. 2022 2 2937 84 GENETIC AND EPIGENETIC ALTERATIONS DURING RENAL CARCINOGENESIS. RENAL CELL CARCINOMA (RCC) IS NOT A SINGLE ENTITY, BUT COMPRISES A GROUP OF TUMORS INCLUDING CLEAR CELL RCC, PAPILLARY RCC AND CHROMOPHOBE RCC, WHICH ARISE FROM THE EPITHELIUM OF RENAL TUBULES. THE MAJORITY OF CLEAR CELL RCCS, THE MAJOR HISTOLOGICAL SUBTYPE, HAVE GENETIC OR EPIGENETIC INACTIVATION OF THE VON HIPPEL-LINDAU (VHL) GENE. GERMLINE MUTATIONS IN THE MET AND FUMARATE HYDRATASE (FH) GENES LEAD TO THE DEVELOPMENT OF TYPE 1 AND TYPE 2 PAPILLARY RCCS, RESPECTIVELY, AND SUCH MUTATIONS OF EITHER THE TSC1 OR TSC2 GENE INCREASE THE RISK OF RCC. GENOME-WIDE COPY NUMBER ALTERATION ANALYSIS HAS SUGGESTED THAT LOSS OF CHROMOSOME 3P AND GAIN OF CHROMOSOMES 5Q AND 7 MAY BE COPY NUMBER ABERRATIONS INDISPENSABLE FOR THE DEVELOPMENT OF CLEAR CELL RCC. WHEN CHROMOSOME 1P, 4, 9, 13Q OR 14Q IS ALSO LOST, MORE CLINICOPATHOLOGICALLY AGGRESSIVE CLEAR CELL RCC MAY DEVELOP. SINCE RENAL CARCINOGENESIS IS ASSOCIATED WITH NEITHER CHRONIC INFLAMMATION NOR PERSISTENT VIRAL INFECTION, AND HARDLY ANY HISTOLOGICAL CHANGE IS EVIDENT IN CORRESPONDING NON-TUMOROUS RENAL TISSUE FROM PATIENTS WITH RENAL TUMORS, PRECANCEROUS CONDITIONS IN THE KIDNEY HAVE BEEN RARELY DESCRIBED. HOWEVER, REGIONAL DNA HYPERMETHYLATION ON C-TYPE CPG ISLANDS HAS ALREADY ACCUMULATED IN SUCH NON-CANCEROUS RENAL TISSUES, SUGGESTING THAT, FROM THE VIEWPOINT OF ALTERED DNA METHYLATION, THE PRESENCE OF PRECANCEROUS CONDITIONS CAN BE RECOGNIZED EVEN IN THE KIDNEY. GENOME-WIDE DNA METHYLATION PROFILES IN PRECANCEROUS CONDITIONS ARE BASICALLY INHERITED BY THE CORRESPONDING CLEAR CELL RCCS DEVELOPING IN INDIVIDUAL PATIENTS: DNA METHYLATION ALTERATIONS AT THE PRECANCEROUS STAGE MAY FURTHER PREDISPOSE RENAL TISSUE TO EPIGENETIC AND GENETIC ALTERATIONS, GENERATE MORE MALIGNANT CANCERS, AND EVEN DETERMINE PATIENT OUTCOME. THE LIST OF TUMOR-RELATED GENES SILENCED BY DNA HYPERMETHYLATION HAS RECENTLY BEEN INCREASING. GENETIC AND EPIGENETIC PROFILING PROVIDES AN OPTIMAL MEANS OF PROGNOSTICATION FOR PATIENTS WITH RCCS. RECENTLY DEVELOPED HIGH-THROUGHPUT TECHNOLOGIES FOR GENETIC AND EPIGENETIC ANALYSES WILL FURTHER ACCELERATE THE IDENTIFICATION OF KEY MOLECULES FOR USE IN THE PREVENTION, DIAGNOSIS AND THERAPY OF RCCS. 2010 3 4423 40 MOLECULAR AND IMMUNOLOGIC MARKERS OF KIDNEY CANCER-POTENTIAL APPLICATIONS IN PREDICTIVE, PREVENTIVE AND PERSONALIZED MEDICINE. KIDNEY CANCER IS ONE OF THE DEADLIEST MALIGNANCIES DUE TO FREQUENT LATE DIAGNOSIS (33 % OR RENAL CELL CARCINOMA ARE METASTATIC AT DIAGNOSIS) AND POOR TREATMENT OPTIONS. THERE ARE TWO MAJOR SUBTYPES OF KIDNEY CANCER: RENAL CELL CARCINOMA (RCC) AND RENAL PELVIS CARCINOMA. THE RISK FACTORS FOR RCC, ACCOUNTING FOR MORE THAN 90 % OF ALL KIDNEY CANCERS, ARE SMOKING, OBESITY, HYPERTENSION, MISUSE OF PAIN MEDICATION, AND SOME GENETIC DISEASES. THE MOST COMMON MOLECULAR MARKERS OF KIDNEY CANCER INCLUDE MUTATIONS AND EPIGENETIC INACTIVATION OF VON HIPPEL-LINDAU (VHL) GENE, GENES OF VASCULAR ENDOTHELIAL GROWTH FACTOR (VEGF) PATHWAY, AND CARBONIC ANHYDRASE IX (CIAX). THE ROLE OF EPIGENETIC PATHWAYS, INCLUDING DNA METHYLATION AND CHROMATIN STRUCTURE REMODELING, WAS ALSO DEMONSTRATED. IMMUNOLOGIC PROPERTIES OF RCC ENABLE THIS TYPE OF TUMOR TO ESCAPE IMMUNE RESPONSE EFFECTIVELY. AN IMPORTANT ROLE IN THIS PROCESS IS PLAYED BY TUMOR-ASSOCIATED MACROPHAGES THAT DEMONSTRATE MIXED M1/M2 PHENOTYPE. IN THIS REVIEW, WE DISCUSS MOLECULAR AND CELLULAR ASPECTS FOR RCC DEVELOPMENT AND CURRENT STATE OF KNOWLEDGE ALLOWING PERSONALIZED APPROACHES FOR DIAGNOSTICS AND PROGNOSTIC PREDICTION OF THIS DISEASE. A SET OF MACROPHAGE MARKERS IS SUGGESTED FOR THE ANALYSIS OF THE ASSOCIATION OF MACROPHAGE PHENOTYPE AND DISEASE PROGNOSIS. 2015 4 342 45 ALTERATIONS OF DNA METHYLATION ASSOCIATED WITH ABNORMALITIES OF DNA METHYLTRANSFERASES IN HUMAN CANCERS DURING TRANSITION FROM A PRECANCEROUS TO A MALIGNANT STATE. ALTERATIONS OF DNA METHYLATION ARE ONE OF THE MOST CONSISTENT EPIGENETIC CHANGES IN HUMAN CANCERS. HUMAN CANCERS GENERALLY SHOW GLOBAL DNA HYPOMETHYLATION ACCOMPANIED BY REGION-SPECIFIC HYPERMETHYLATION. ALTERATIONS OF DNA METHYLATION MAY RESULT IN CHROMOSOMAL INSTABILITY AS A RESULT OF CHANGES IN CHROMATIN STRUCTURE. DNA HYPERMETHYLATION OF CPG ISLANDS SILENCES VARIOUS TUMOR-RELATED GENES. ALTERATIONS OF DNA METHYLATION ARE FREQUENTLY OBSERVED IN CANCERS ASSOCIATED WITH CHRONIC INFLAMMATION AND/OR PERSISTENT INFECTION WITH VIRUSES OR OTHER PATHOGENIC MICROORGANISMS, SUCH AS HEPATITIS B OR C VIRUSES, EPSTEIN-BARR VIRUS, HUMAN PAPILLOMAVIRUS AND HELICOBACTER PYLORI, OR WITH CIGARETTE SMOKING. ACCUMULATING EVIDENCE SUGGESTS THAT ALTERATIONS OF DNA METHYLATION ARE INVOLVED EVEN IN THE EARLY AND PRECANCEROUS STAGES. ON THE OTHER HAND, IN PATIENTS WITH CANCERS, ABERRANT DNA METHYLATION IS SIGNIFICANTLY ASSOCIATED WITH POORER TUMOR DIFFERENTIATION, TUMOR AGGRESSIVENESS AND POOR PROGNOSIS. PRECANCEROUS CONDITIONS SHOWING ALTERATIONS OF DNA METHYLATION MAY PROGRESS RAPIDLY AND GENERATE MORE MALIGNANT CANCERS. DNA METHYLTRANSFERASE (DNMT) 1 OVER-EXPRESSION IS NOT A SECONDARY RESULT OF INCREASED CELL PROLIFERATIVE ACTIVITY BUT IS SIGNIFICANTLY CORRELATED WITH THE CPG ISLAND METHYLATOR PHENOTYPE, WHICH IS DEFINED AS FREQUENT DNA HYPERMETHYLATION OF C-TYPE CPG ISLANDS THAT ARE USUALLY METHYLATED IN A CANCER-SPECIFIC (NOT AGE-DEPENDENT) MANNER. SPLICING ALTERATION OF DNMT3B MAY RESULT IN CHROMOSOMAL INSTABILITY THROUGH DNA HYPOMETHYLATION OF PERICENTROMERIC SATELLITE REGIONS. ALTERATION OF DNA METHYLATION MAY BECOME AN INDICATOR FOR CARCINOGENETIC RISK ESTIMATION AND EARLY DIAGNOSIS OF CANCERS AND A BIOLOGICAL PREDICTOR OF POOR PROGNOSIS IN PATIENTS WITH CANCERS. CORRECTION OF DNA METHYLATION STATUS MAY OFFER A NEW STRATEGY FOR PREVENTION AND THERAPY OF CANCERS. 2007 5 3067 49 GENOME-WIDE DNA METHYLATION PROFILES IN PRECANCEROUS CONDITIONS AND CANCERS. ALTERATIONS OF DNA METHYLATION, WHICH RESULT IN CHROMOSOMAL INSTABILITY AND SILENCING OF TUMOR-RELATED GENES, ARE AMONG THE MOST CONSISTENT EPIGENETIC CHANGES OBSERVED IN HUMAN CANCERS. ANALYSIS OF TISSUE SPECIMENS HAS REVEALED THAT DNA METHYLATION ALTERATIONS PARTICIPATE IN MULTISTAGE CARCINOGENESIS, EVEN FROM THE EARLY AND PRECANCEROUS STAGES, ESPECIALLY IN ASSOCIATION WITH CHRONIC INFLAMMATION AND/OR PERSISTENT VIRAL INFECTION, SUCH AS CHRONIC HEPATITIS OR LIVER CIRRHOSIS RESULTING FROM INFECTION WITH HEPATITIS B OR C VIRUS. DNA METHYLATION ALTERATIONS CAN ACCOUNT FOR THE HISTOLOGICAL HETEROGENEITY AND CLINICOPATHOLOGICAL DIVERSITY OF HUMAN CANCERS. OVEREXPRESSION OF DNA METHYLTRANSFERASE 1 IS NOT A SECONDARY RESULT OF INCREASED CELL PROLIFERATIVE ACTIVITY, BUT IS SIGNIFICANTLY CORRELATED WITH ACCUMULATION OF DNA HYPERMETHYLATION IN CPG ISLANDS OF TUMOR-RELATED GENES. ALTERATION OF DNA METHYLTRANSFERASE 3B SPLICING MAY RESULT IN CHROMOSOMAL INSTABILITY THROUGH DNA HYPOMETHYLATION IN PERICENTROMERIC SATELLITE REGIONS. GENOME-WIDE ANALYSIS OF DNA METHYLATION STATUS HAS REVEALED THAT THE DNA METHYLATION PROFILE AT THE PRECANCEROUS STAGE IS BASICALLY INHERITED BY THE CORRESPONDING CANCERS DEVELOPING IN INDIVIDUAL PATIENTS. DNA METHYLATION STATUS IS NOT SIMPLY ALTERED AT THE PRECANCEROUS STAGE; RATHER, DNA METHYLATION ALTERATIONS AT THE PRECANCEROUS STAGE MAY CONFER VULNERABILITY TO FURTHER GENETIC AND EPIGENETIC ALTERATIONS, GENERATE MORE MALIGNANT CANCERS, AND THUS DETERMINE PATIENT OUTCOME. THEREFORE, GENOME-WIDE DNA METHYLATION PROFILING MAY PROVIDE OPTIMAL INDICATORS FOR CARCINOGENETIC RISK ESTIMATION AND PROGNOSTICATION, AND THUS PROVIDE AN AVENUE FOR CANCER PREVENTION AND THERAPY ON AN INDIVIDUAL BASIS. 2010 6 1582 42 DNA METHYLATION PROFILES IN PRECANCEROUS TISSUE AND CANCERS: CARCINOGENETIC RISK ESTIMATION AND PROGNOSTICATION BASED ON DNA METHYLATION STATUS. ALTERATIONS IN DNA METHYLATION, WHICH ARE ASSOCIATED WITH DNA METHYLTRANSFERASE ABNORMALITIES AND RESULT IN SILENCING OF TUMOR-RELATED GENES AND CHROMOSOMAL INSTABILITY, ARE INVOLVED EVEN IN PRECANCEROUS CHANGES IN VARIOUS ORGANS. DNA METHYLATION ALTERATIONS ALSO ACCOUNT FOR THE HISTOLOGICAL HETEROGENEITY AND CLINICOPATHOLOGICAL DIVERSITY OF HUMAN CANCERS. THEREFORE, WE HAVE ANALYZED DNA METHYLATION ON A GENOME-WIDE SCALE IN CLINICAL TISSUE SAMPLES. OUR APPROACH USING THE BACTERIAL ARTIFICIAL CHROMOSOME ARRAY-BASED METHYLATED CPG ISLAND AMPLIFICATION METHOD HAS REVEALED THAT DNA METHYLATION ALTERATIONS CORRELATED WITH THE FUTURE DEVELOPMENT OF MORE MALIGNANT CANCERS ARE ALREADY ACCUMULATED AT THE PRECANCEROUS STAGE IN THE KIDNEY, LIVER AND URINARY TRACT. DNA METHYLATION PROFILES AT PRECANCEROUS STAGES ARE BASICALLY INHERITED BY THE CORRESPONDING CANCERS DEVELOPING IN INDIVIDUAL PATIENTS. SUCH DNA METHYLATION ALTERATIONS MAY CONFER VULNERABILITY TO FURTHER GENETIC AND EPIGENETIC ALTERATIONS, GENERATE MORE MALIGNANT CANCERS, AND THUS DETERMINE PATIENT OUTCOME. ON THE BASIS OF BACTERIAL ARTIFICIAL CHROMOSOME ARRAY-BASED METHYLATED CPG ISLAND AMPLIFICATION DATA, INDICATORS FOR CARCINOGENETIC RISK ESTIMATION HAVE BEEN ESTABLISHED USING LIVER TISSUE SPECIMENS FROM PATIENTS WITH HEPATITIS VIRUS INFECTION, CHRONIC HEPATITIS AND LIVER CIRRHOSIS OR HISTOLOGICALLY NORMAL UROTHELIA, AND FOR PROGNOSTICATION USING BIOPSY OR SURGICALLY RESECTED SPECIMENS FROM PATIENTS WITH RENAL CELL CARCINOMA, HEPATOCELLULAR CARCINOMA AND UROTHELIAL CARCINOMA. SUCH GENOME-WIDE DNA METHYLATION PROFILING HAS NOW FIRMLY ESTABLISHED THE CLINICAL RELEVANCE OF TRANSLATIONAL EPIGENETICS. 2010 7 3686 32 INFLAMMATION-RELATED ABERRANT PATTERNS OF DNA METHYLATION: DETECTION AND ROLE IN EPIGENETIC DEREGULATION OF CANCER CELL TRANSCRIPTOME. IT IS NOW APPARENT THAT EPIGENETIC ABNORMALITIES, IN PARTICULAR ALTERED DNA METHYLATION, PLAY A CRUCIAL ROLE IN THE DEVELOPMENT AND PROGRESSION OF HUMAN CANCERS. DNA HYPERMETHYLATION AT PROMOTER CPG ISLANDS IS NOW RECOGNIZED AS A THIRD MECHANISM BY WHICH INACTIVATION OF TUMOR SUPPRESSOR GENES OCCURS. ABERRANT CPG ISLAND HYPERMETHYLATION IS ALSO FREQUENTLY OBSERVED IN CHRONIC INFLAMMATION AND PRECANCEROUS LESIONS, WHICH SUGGESTS THAT IT IS AN EARLY EVENT IN TUMORIGENESIS THAT COULD SERVE AS A USEFUL TUMOR MARKER. A VARIETY OF SCREENING TECHNIQUES HAVE BEEN DEVELOPED FOR GENOME-WIDE SCREENING OF METHYLATION STATUS. OF THOSE, TRANSCRIPTOME ANALYSIS COUPLED WITH PHARMACOLOGICAL UNMASKING HAS EMERGED AS A POWERFUL TOOL FOR REVEALING DNA METHYLATION PATTERNS IN CANCER CELLS AND IDENTIFYING NEW TUMOR MARKER CANDIDATES. 2009 8 606 37 BEYOND GENETICS--THE EMERGING ROLE OF EPIGENETIC CHANGES IN HEMATOPOIETIC MALIGNANCIES. THE TERM EPIGENETIC REFERS TO A HERITABLE CHANGE IN GENE EXPRESSION THAT IS MEDIATED BY MECHANISMS OTHER THAN ALTERATIONS IN THE PRIMARY NUCLEOTIDE SEQUENCE. DNA METHYLATION AT CYTOSINE BASES THAT ARE LOCATED 5' TO GUANOSINE WITHIN A CPG DINUCLEOTIDE IS THE MAIN EPIGENETIC MODIFICATION IN HUMANS. PATTERNS OF DNA METHYLATION ARE PROFOUNDLY DERANGED IN HUMAN CANCER AND COMPRISE GENOME-WIDE LOSSES AS WELL AS REGIONAL GAINS IN DNA METHYLATION. HYPERMETHYLATION OF CPG ISLANDS WITHIN GENE PROMOTER REGIONS IS ASSOCIATED WITH TRANSCRIPTIONAL INACTIVATION AND REPRESENTS, IN ADDITION TO GENETIC ABERRATIONS, AN IMPORTANT MECHANISM OF GENE SILENCING IN THE PATHOGENESIS OF HEMATOPOIETIC MALIGNANCIES. THIS EPIGENETIC PHENOMENON ACTS AS AN ALTERNATIVE TO MUTATIONS AND DELETIONS TO DISRUPT TUMOR SUPPRESSOR GENE FUNCTION. A LARGE NUMBER OF GENES INVOLVING FUNDAMENTAL CELLULAR PATHWAYS MAY BE AFFECTED IN VIRTUALLY ALL TYPES OF HUMAN CANCER BY ABERRANT CPG ISLAND METHYLATION IN ASSOCIATION WITH TRANSCRIPTIONAL SILENCING. ALTERED METHYLATION PATTERNS CAN BE USED AS BIOMARKERS FOR CANCER DETECTION, ASSESSMENT OF PROGNOSIS, AND PREDICTION OF RESPONSE TO ANTITUMOR TREATMENT. FURTHERMORE, CLINICAL TRIALS USING EPIGENETICALLY TARGETED THERAPIES HAVE YIELDED PROMISING RESULTS FOR ACUTE AND CHRONIC LEUKEMIAS AS WELL AS FOR MYELODYSPLASTIC SYNDROMES. THE EXPLORATION OF OUR GROWING KNOWLEDGE ABOUT EPIGENETIC ABERRATIONS MAY HELP DEVELOP NOVEL STRATEGIES FOR THE DIAGNOSIS AND TREATMENT OF HEMATOPOIETIC MALIGNANCIES IN THE FUTURE. 2004 9 5742 30 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 10 2122 29 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 11 332 37 ALTERATION OF EPIGENETIC PROFILE IN HUMAN HEPATOCELLULAR CARCINOMA AND ITS CLINICAL IMPLICATIONS. HEPATOCELLULAR CARCINOMA (HCC) IS A COMMON CANCER WORLDWIDE AND DEVELOPS AGAINST A BACKGROUND OF CHRONIC LIVER DAMAGE. A VARIETY OF HCC-RELATED GENES ARE KNOWN TO BE ALTERED BY GENETIC AND EPIGENETIC MECHANISMS. THEREFORE, INFORMATION REGARDING ALTERATION OF THE GENETIC AND EPIGENETIC PROFILES IN HCC IS ESSENTIAL FOR UNDERSTANDING THE BIOLOGY OF THIS TYPE OF TUMOR. METHYLATION AT CPG SITES IN GENE PROMOTERS IS KNOWN TO AFFECT THE TRANSCRIPTION OF THE CORRESPONDING GENES. ABNORMAL REGIONAL HYPERMETHYLATION IS OBSERVED IN THE 5' REGION OF SEVERAL TUMOR SUPPRESSOR GENES (TSGS) IN HCC, AND THIS HYPERMETHYLATION MAY PROMOTE CARCINOGENESIS THROUGH THE TRANSCRIPTIONAL INACTIVATION OF DOWNSTREAM TSGS. THE DNA DAMAGE INDUCED BY OXIDATION IS A TRIGGER OF ABNORMAL DNA METHYLATION AND INACTIVATION OF TSGS THROUGH RECRUITMENT OF THE POLYCOMB REPRESSIVE COMPLEX TO THE PROMOTER SEQUENCE. THUS, OXIDATIVE STRESS MAY BE RESPONSIBLE FOR THE EMERGENCE OF HCC FROM CHRONIC HEPATITIS AND LIVER CIRRHOSIS THROUGH THE EPIGENETIC ALTERATION OF TSGS. THERE HAVE BEEN SEVERAL ATTEMPTS TO APPLY EPIGENETIC INFORMATION TO THE DIAGNOSIS AND TREATMENT OF HCC. THE PREDICTIVE VALUE OF SELECTED METHYLATION EVENTS ON SURVIVAL IN HCC PATIENTS HAS BEEN REPORTED, AND THE METHYLATION PROFILE OF BACKGROUND LIVER COULD BE ASSOCIATED WITH RECURRENCE-FREE SURVIVAL OF HCC PATIENTS WHO HAVE UNDERGONE HEPATECTOMY. ANOTHER STUDY DETECTED METHYLATED DNA FROM HCC CELLS IN SERUM, AND THE CIRCULATING TUMOR DNA WAS REGARDED AS A POTENTIAL TUMOR MARKER. IN ADDITION, SEVERAL TRIALS OF HCC THERAPY HAVE TARGETED THE EPIGENETIC MACHINERY AND WERE BASED UPON COMPREHENSIVE ANALYSES OF DNA METHYLATION OF THIS TYPE OF TUMOR. HERE, WE PRESENT AN OVERVIEW OF RESEARCH REGARDING DNA METHYLATION STATUS IN HUMAN HCC AND DESCRIBE THE CLINICAL APPLICATION OF EPIGENETIC INFORMATION TO HCC. 2014 12 2033 34 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 13 4531 44 MULTILAYER-OMICS ANALYSES OF HUMAN CANCERS: EXPLORATION OF BIOMARKERS AND DRUG TARGETS BASED ON THE ACTIVITIES OF THE INTERNATIONAL HUMAN EPIGENOME CONSORTIUM. EPIGENETIC ALTERATIONS CONSISTING MAINLY OF DNA METHYLATION ALTERATIONS AND HISTONE MODIFICATION ALTERATIONS ARE FREQUENTLY OBSERVED IN CANCERS ASSOCIATED WITH CHRONIC INFLAMMATION AND/OR PERSISTENT INFECTION WITH VIRUSES OR OTHER PATHOGENIC MICROORGANISMS, OR WITH CIGARETTE SMOKING. ACCUMULATING EVIDENCE SUGGESTS THAT ALTERATIONS OF DNA METHYLATION ARE INVOLVED EVEN IN THE EARLY AND PRECANCEROUS STAGES. ON THE OTHER HAND, IN PATIENTS WITH CANCERS, ABERRANT DNA METHYLATION IS FREQUENTLY ASSOCIATED WITH TUMOR AGGRESSIVENESS AND POOR PATIENT OUTCOME. RECENTLY, EPIGENOME ALTERATIONS HAVE BEEN ATTRACTING A GREAT DEAL OF ATTENTION FROM RESEARCHERS WHO ARE FOCUSING ON NOT ONLY CANCERS BUT ALSO NEURONAL, IMMUNE AND METABOLIC DISORDERS. IN ORDER TO ACCURATELY IDENTIFY DISEASE-SPECIFIC EPIGENOME PROFILES THAT COULD BE POTENTIALLY APPLICABLE FOR DISEASE PREVENTION, DIAGNOSIS AND THERAPY, STRICT COMPARISON WITH STANDARD EPIGENOME PROFILES OF NORMAL TISSUES IS INDISPENSABLE. HOWEVER, EPIGENOME MECHANISMS SHOW HETEROGENEITY AMONG TISSUES AND CELL LINEAGES. THEREFORE, IT IS NOT EASY TO OBTAIN A COMPREHENSIVE PICTURE OF STANDARD EPIGENOME PROFILES OF NORMAL TISSUES. IN 2010, THE INTERNATIONAL HUMAN EPIGENOME CONSORTIUM (IHEC) WAS ESTABLISHED TO COORDINATE THE PRODUCTION OF REFERENCE MAPS OF HUMAN EPIGENOMES FOR KEY CELLULAR STATES. IN ORDER TO GAIN SUBSTANTIAL COVERAGE OF THE HUMAN EPIGENOME, THE IHEC HAS SET AN AMBITIOUS GOAL TO DECIPHER AT LEAST 1000 EPIGENOMES WITHIN THE NEXT 7-10 YEARS. WE CONSIDER THAT PATHWAY ANALYSIS USING GENES SHOWING MULTILAYER-OMICS ABNORMALITIES, INCLUDING GENOME, EPIGENOME, TRANSCRIPTOME, PROTEOME AND METABOLOME ABNORMALITIES, MAY BE USEFUL FOR ELUCIDATING THE MOLECULAR BACKGROUND OF PATHOGENESIS AND FOR EXPLORING POSSIBLE THERAPEUTIC TARGETS FOR EACH DISEASE. 2014 14 5770 31 SPECIFIC MOLECULAR SIGNATURES OF NON-TUMOR LIVER TISSUE MAY PREDICT A RISK OF HEPATOCARCINOGENESIS. HEPATOCELLULAR CARCINOMA (HCC) IS ONE OF THE MOST COMMON HUMAN CANCERS AND A MAJOR CAUSE OF CANCER-RELATED DEATH WORLDWIDE. THE BLEAK OUTCOMES OF HCC PATIENTS EVEN AFTER CURATIVE TREATMENT HAVE BEEN, AT LEAST PARTIALLY, ATTRIBUTED TO ITS MULTICENTRIC ORIGIN. THEREFORE, IT IS NECESSARY TO EXAMINE NOT ONLY TUMOR TISSUE BUT ALSO NON-TUMOR LIVER TISSUE TO INVESTIGATE THE MOLECULAR MECHANISMS OPERATING DURING HEPATOCARCINOGENESIS BASED ON THE CONCEPT OF "FIELD CANCERIZATION". SEVERAL STUDIES PREVIOUSLY INVESTIGATED THE ASSOCIATION OF MOLECULAR ALTERATIONS IN NON-TUMOR LIVER TISSUE WITH CLINICAL FEATURES AND PROGNOSIS IN HCC PATIENTS ON A GENOME-WIDE SCALE. IN PARTICULAR, SPECIFIC ALTERATIONS OF DNA METHYLATION PROFILES HAVE BEEN CONFIRMED IN NON-TUMOR LIVER TISSUE. THIS REVIEW FOCUSES ON THE POSSIBLE CLINICAL VALUE OF ARRAY-BASED COMPREHENSIVE ANALYSES OF MOLECULAR ALTERATIONS, ESPECIALLY ABERRANT DNA METHYLATION, IN NON-TUMOR LIVER TISSUE TO CLARIFY THE RISK OF HEPATOCARCINOGENESIS. CARCINOGENETIC RISK ESTIMATION BASED ON SPECIFIC METHYLATION SIGNATURES MAY BE ADVANTAGEOUS FOR CLOSE FOLLOW-UP OF PATIENTS WHO ARE AT HIGH RISK OF HCC DEVELOPMENT. FURTHERMORE, EPIGENETIC THERAPIES FOR PATIENTS WITH CHRONIC LIVER DISEASES MAY BE HELPFUL TO REDUCE THE RISK OF HCC DEVELOPMENT BECAUSE EPIGENETIC ALTERATIONS ARE POTENTIALLY REVERSIBLE, AND THUS PROVIDE PROMISING MOLECULAR TARGETS FOR THERAPEUTIC INTERVENTION. 2014 15 5360 37 RECENT ADVANCEMENTS IN COMPREHENSIVE GENETIC ANALYSES FOR HUMAN HEPATOCELLULAR CARCINOMA. HEPATOCELLULAR CARCINOMA (HCC) TYPICALLY DEVELOPS IN THE LIVER WITH CHRONIC HEPATITIS AND CIRRHOSIS, AND ACTIVATION OF ONCOGENES AND INACTIVATION OF TUMOR SUPPRESSOR GENES OCCURS DURING CARCINOGENESIS VIA GENETIC AND EPIGENETIC MECHANISMS. RECENT ADVANCEMENTS IN THE DEVELOPMENT OF ANALYSES FOR EXAMINING THE CANCER GENOME HAVE REVEALED INFORMATION REGARDING GENETIC ALTERATIONS IN HCC TISSUES. ACCORDING TO PREVIOUS STUDIES, THE INCIDENCE OF RECURRENT GENETIC ALTERATIONS IN INDIVIDUAL GENES WAS THOUGHT TO BE RELATIVELY RARE AND LIMITED TO A SUBSET OF A FEW CANCER-SPECIFIC GENES SUCH AS TUMOR SUPPRESSOR P53, RB GENES AND ONCOGENES SUCH AS CTNNB1. HOWEVER, RECENT WHOLE-GENOME ANALYSES AND EXOME SEQUENCING OF TUMOR DNA HAVE REVEALED NUMEROUS NOVEL ALTERATIONS OF CANCER-RELATED GENES AND PATHWAYS CRITICAL FOR HCC DEVELOPMENT. IN ADDITION, VARIOUS RISK FACTORS FOR HCC, SUCH AS THE PRESENCE OR ABSENCE OF HEPATITIS B AND C VIRUS, MAY AFFECT THE MUTATION PROFILE OF THE CORRESPONDING CANCER GENOME. ON THE OTHER HAND, GENOME-WIDE ASSOCIATION STUDIES HAVE ALSO IDENTIFIED IMPORTANT SINGLE-NUCLEOTIDE POLYMORPHISMS INVOLVED IN HCC DEVELOPMENT, WHICH MAY ALLOW DETECTION OF A GROUP AT HIGH RISK OF HCC EMERGENCE. SUCH ANALYSES WILL CLARIFY HOW THIS MALIGNANCY CAN BE TREATED, DIAGNOSED AND PREVENTED MORE EFFECTIVELY. 2013 16 1435 44 DIFFERENTIAL METHYLATION LANDSCAPE OF PANCREATIC DUCTAL ADENOCARCINOMA AND ITS PRECANCEROUS LESIONS. BACKGROUND: PANCREATIC CANCER IS ONE OF THE MOST LETHAL DISEASES WITH AN INCIDENCE ALMOST EQUAL TO THE MORTALITY. IN ADDITION TO HAVING GENETIC CAUSES, CANCER CAN ALSO BE CONSIDERED AN EPIGENETIC DISEASE. DNA METHYLATION IS THE PREMIER EPIGENETIC MODIFICATION AND PATTERNS OF ABERRANT DNA METHYLATION ARE RECOGNIZED TO BE A COMMON HALLMARK OF HUMAN TUMOR. IN THE MULTISTAGE CARCINOGENESIS OF PANCREAS STARTING FROM PRECANCEROUS LESIONS TO PANCREATIC DUCTAL ADENOCARCINOMA (PDAC), THE EPIGENETIC CHANGES PLAY A SIGNIFICANT ROLE. DATA SOURCES: RELEVANT STUDIES FOR THIS REVIEW WERE DERIVED VIA AN EXTENSIVE LITERATURE SEARCH IN PUBMED VIA USING VARIOUS KEYWORDS SUCH AS PANCREATIC DUCTAL ADENOCARCINOMA, PRECANCEROUS LESIONS, METHYLATION PROFILE, EPIGENETIC BIOMARKERS THAT ARE RELEVANT DIRECTLY OR CLOSELY ASSOCIATED WITH THE CONCERNED AREA OF OUR INTEREST. THE LITERATURE SEARCH WAS INTENSIVELY DONE CONSIDERING A TIME FRAME OF 20 YEARS (1998-2018). RESULT: IN THIS REVIEW WE HAVE HIGHLIGHTED THE HYPERMETHYLATION AND HYPOMETHYLATION OF THE PRECANCEROUS PDAC LESIONS (PANCREATIC INTRA-EPITHELIAL NEOPLASIA, INTRADUCTAL PAPILLARY MUCINOUS NEOPLASM, MUCINOUS CYSTIC NEOPLASM AND CHRONIC PANCREATITIS) AND PDAC ALONG WITH THE POTENTIAL BIOMARKERS. WE HAVE ALSO ACHIEVED THE EARLY EPIGENETIC DRIVER THAT LEADS TO PROGRESSION FROM PRECANCEROUS LESIONS TO PDAC. A BUNCH OF EPIGENETIC DRIVER GENES LEADS TO PROGRESSION OF PRECANCEROUS LESIONS TO PDAC (PPENK, APC, P14/5/16/17, HMLH1 AND MGMT) ARE ALSO DOCUMENTED. WE SUMMARIZED THE IMPORTANCE OF THESE OBSERVATIONS IN THERAPEUTICS AND DIAGNOSIS OF PDAC HENCE IDENTIFYING THE POTENTIAL USE OF EPIGENETIC BIOMARKERS IN EPIGENETIC TARGETED THERAPY. EPIGENETIC INACTIVATION OCCURS BY HYPERMETHYLATION OF CPG ISLANDS IN THE PROMOTER REGIONS OF TUMOR SUPPRESSOR GENES. WE LISTED ALL HYPER- AND HYPOMETHYLATION OF CPG ISLANDS OF SEVERAL GENES IN PDAC INCLUDING ITS PRECANCEROUS LESIONS. CONCLUSIONS: THE CONCEPT OF THE REVIEW WOULD HELP TO UNDERSTAND THEIR BIOLOGICAL EFFECTS, AND TO DETERMINE WHETHER THEY MAY BE SUCCESSFULLY COMBINED WITH OTHER EPIGENETIC DRUGS. HOWEVER, WE NEED TO CONTINUE OUR RESEARCH TO DEVELOP MORE SPECIFIC DNA-DEMETHYLATING AGENTS, WHICH ARE THE TARGETS FOR HYPERMETHYLATED CPG METHYLATION SITES. 2020 17 2483 27 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 18 1269 30 CYTOSINE METHYLATION CHANGES IN ENHANCER REGIONS OF CORE PRO-FIBROTIC GENES CHARACTERIZE KIDNEY FIBROSIS DEVELOPMENT. BACKGROUND: ONE IN ELEVEN PEOPLE IS AFFECTED BY CHRONIC KIDNEY DISEASE, A CONDITION CHARACTERIZED BY KIDNEY FIBROSIS AND PROGRESSIVE LOSS OF KIDNEY FUNCTION. EPIDEMIOLOGICAL STUDIES INDICATE THAT ADVERSE INTRAUTERINE AND POSTNATAL ENVIRONMENTS HAVE A LONG-LASTING ROLE IN CHRONIC KIDNEY DISEASE DEVELOPMENT. EPIGENETIC INFORMATION REPRESENTS A PLAUSIBLE CARRIER FOR MEDIATING THIS PROGRAMMING EFFECT. HERE WE DEMONSTRATE THAT GENOME-WIDE CYTOSINE METHYLATION PATTERNS OF HEALTHY AND CHRONIC KIDNEY DISEASE TUBULE SAMPLES OBTAINED FROM PATIENTS SHOW SIGNIFICANT DIFFERENCES. RESULTS: WE IDENTIFY DIFFERENTIALLY METHYLATED REGIONS AND VALIDATE THESE IN A LARGE REPLICATION DATASET. THE DIFFERENTIALLY METHYLATED REGIONS ARE RARELY OBSERVED ON PROMOTERS, BUT MOSTLY OVERLAP WITH PUTATIVE ENHANCER REGIONS, AND THEY ARE ENRICHED IN CONSENSUS BINDING SEQUENCES FOR IMPORTANT RENAL TRANSCRIPTION FACTORS. THIS INDICATES THEIR IMPORTANCE IN GENE EXPRESSION REGULATION. A CORE SET OF GENES THAT ARE KNOWN TO BE RELATED TO KIDNEY FIBROSIS, INCLUDING GENES ENCODING COLLAGENS, SHOW CYTOSINE METHYLATION CHANGES CORRELATING WITH DOWNSTREAM TRANSCRIPT LEVELS. CONCLUSIONS: OUR REPORT RAISES THE POSSIBILITY THAT EPIGENETIC DYSREGULATION PLAYS A ROLE IN CHRONIC KIDNEY DISEASE DEVELOPMENT VIA INFLUENCING CORE PRO-FIBROTIC PATHWAYS AND CAN AID THE DEVELOPMENT OF NOVEL BIOMARKERS AND FUTURE THERAPEUTICS. 2013 19 186 35 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 20 4479 35 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