1 3213 108 HEART RHYTHM GENOMIC FABRIC IN HYPOXIA. THE MOLECULAR MECHANISMS BY WHICH CHRONIC HYPOXIA, WHETHER CONSTANT (CCH) OR INTERMITTENT (CIH), ALTERS THE HEART RHYTHM ARE STILL UNDER DEBATE. EXPRESSION LEVEL, CONTROL, MATURATIONAL PROFILE AND INTERCOORDINATION OF 54 GENES ENCODING HEART RHYTHM DETERMINANTS (HRDS) WERE ANALYZED IN 36 MICE SUBJECTED FOR 1, 2 OR 4 WEEKS OF THEIR EARLY LIFE TO NORMAL ATMOSPHERIC CONDITIONS OR TO CCH OR CIH. OUR ANALYSIS REVEALED A COMPLEX NETWORK OF GENES ENCODING VARIOUS HEART RATE, INOTROPY AND DEVELOPMENT CONTROLLERS, RECEPTORS, ION CHANNELS AND TRANSPORTERS, ANKYRINS, EPIGENETIC MODULATORS AND INTERCALATED DISC COMPONENTS (ADHERENS, CADHERINS, CATENINS, DESMOSOMAL, GAP AND TIGHT JUNCTION PROTEINS). THE NETWORK IS REMODELED DURING MATURATION AND SUBSTANTIALLY AND DIFFERENTLY ALTERED BY CIH AND CCH. GENE PROMINENCE ANALYSIS THAT RANKS THE GENES ACCORDING TO THEIR EXPRESSION STABILITY AND NETWORKING WITHIN FUNCTIONAL GENE WEBS, CONFIRMED THE HRD STATUS OF CERTAIN EPIGENETIC MODULATORS AND COMPONENTS OF THE INTERCALATED DISCS NOT YET ASSOCIATED WITH ARRHYTHMIA. 2010 2 2071 28 EPIGENETIC CONTROL OF THE E-CADHERIN GENE (CDH1) BY CPG METHYLATION IN COLECTOMY SAMPLES OF PATIENTS WITH ULCERATIVE COLITIS. E-CADHERIN BELONGS TO THE CADHERIN FAMILY OF CALCIUM-DEPENDENT CELL-ADHESION MOLECULES. THE CADHERINS PLAY AN ESSENTIAL ROLE IN BIOLOGICAL PROCESSES SUCH AS ORDERING OF CELL SORTING, MIGRATION, AND DIFFERENTIATION, AND THEIR MALFUNCTIONING IS CONNECTED WITH NEOPLASIA. NEOPLASTIC PROGRESSION IN PATIENTS WITH CHRONIC ULCERATIVE COLITIS IS CHARACTERIZED BY THE DEVELOPMENT OF EPITHELIAL DYSPLASIA. TRANSCRIPTIONAL SILENCING OF TUMOR-SUPPRESSOR GENES BY PROMOTER METHYLATION HAS BEEN OBSERVED IN DIFFERENT TYPES OF HUMAN CANCERS AND DYSPLASIA. TO EXPLORE THE MODE OF E-CADHERIN REGULATION, 156 BIOPSY SAMPLES FROM 26 PATIENTS WITH LONG-STANDING ULCERATIVE COLITIS WERE SCREENED. TO DETECT THE METHYLATION STATUS OF OUR SAMPLES, A METHYLATION-SPECIFIC PCR WAS APPLIED. METHYLATION OF THE E-CADHERIN (CDH1) PROMOTER WAS DETECTED IN 93% OF THE PATIENTS WITH DYSPLASTIC BIOPSY SAMPLES, IN CONTRAST TO ONLY 6% OF THE PATIENTS WITHOUT DYSPLASIA (P < 0.001). WE ALSO EXAMINED THE LEVEL OF SYNTHESIS OF E-CADHERIN PROTEIN BY IMMUNOHISTOCHEMICAL STAINING IN DIFFERENT PARAFFIN-EMBEDDED SAMPLES OF DYSPLASTIC AND NON-DYSPLASTIC ORIGIN IN A SUBSET OF OUR PATIENTS. SAMPLES WITH DYSPLASIA DISPLAYED REDUCED LEVELS, WHEREAS SAMPLES WITHOUT DYSPLASIA REVEALED NORMAL E-CADHERIN PROTEIN SYNTHESIS. THESE RESULTS SHOW THAT THE E-CADHERIN PROMOTER IS SUBJECTED TO EPIGENETIC CONTROL IN COLORECTAL ULCERATION. OBVIOUSLY, THIS EVENT MAY PLAY AN IMPORTANT ROLE IN THE PROGRESSION FROM CHRONIC INFLAMMATION TO COLORECTAL CANCER. FOR THIS REASON, METHYLATION OF THE CDH1 PROMOTER IS AN ATTRACTIVE NEW BIOMARKER FOR DETECTING ULCERATIVE COLITIS PATIENTS WITH A HIGH RISK FOR DEVELOPING COLORECTAL CANCERS. 2002 3 254 24 ADVANCES IN ASTHMA 2015: ACROSS THE LIFESPAN. IN 2015, PROGRESS IN UNDERSTANDING ASTHMA RANGED FROM INSIGHTS TO ASTHMA INCEPTION, EXACERBATIONS, AND SEVERITY TO ADVANCEMENTS THAT WILL IMPROVE DISEASE MANAGEMENT THROUGHOUT THE LIFESPAN. 2015'S INSIGHTS TO ASTHMA INCEPTION INCLUDED HOW THE INTESTINAL MICROBIOME AFFECTS ASTHMA EXPRESSION WITH THE IDENTIFICATION OF SPECIFIC GASTROINTESTINAL BACTERIAL TAXA IN EARLY INFANCY ASSOCIATED WITH LESS ASTHMA RISK, POSSIBLY BY PROMOTING REGULATORY IMMUNE DEVELOPMENT AT A CRITICAL EARLY AGE. THE RELEVANCE OF EPIGENETIC MECHANISMS IN REGULATING ASTHMA-RELATED GENE EXPRESSION WAS STRENGTHENED. PREDICTING AND PREVENTING EXACERBATIONS THROUGHOUT LIFE MIGHT HELP TO REDUCE PROGRESSIVE LUNG FUNCTION DECREASE AND DISEASE SEVERITY IN ADULTHOOD. ALTHOUGH ALLERGY HAS LONG BEEN LINKED TO ASTHMA EXACERBATIONS, A MECHANISM THROUGH WHICH IGE IMPAIRS RHINOVIRUS IMMUNITY AND UNDERLIES ASTHMA EXACERBATIONS WAS DEMONSTRATED AND IMPROVED BY ANTI-IGE THERAPY (OMALIZUMAB). OTHER KEY MOLECULAR PATHWAYS UNDERLYING ASTHMA EXACERBATIONS, SUCH AS CADHERIN-RELATED FAMILY MEMBER 3 (CDHR3) AND OROSOMUCOID LIKE 3 (ORMDL3), WERE ELUCIDATED. NEW ANTI-IL-5 THERAPEUTICS, MEPOLIZUMAB AND RESLIZUMAB, WERE US FOOD AND DRUG ADMINISTRATION APPROVED FOR THE TREATMENT OF PATIENTS WITH SEVERE EOSINOPHILIC ASTHMA. IN A CLINICAL TRIAL THE NOVEL THERAPEUTIC INHALED GATA3 MRNA-SPECIFIC DNAZYME ATTENUATED EARLY- AND LATE-PHASE ALLERGIC RESPONSES TO INHALED ALLERGEN. THESE CURRENT FINDINGS ARE SIGNIFICANT STEPS TOWARD ADDRESSING UNMET NEEDS IN ASTHMA PREVENTION, SEVERITY MODIFICATION, DISPARITIES, AND LIFESPAN OUTCOMES. 2016 4 185 24 ACCUMULATION OF ABERRANT CPG HYPERMETHYLATION BY HELICOBACTER PYLORI INFECTION PROMOTES DEVELOPMENT AND PROGRESSION OF GASTRIC MALT LYMPHOMA. ABERRANT DNA HYPERMETHYLATION IS AN IMPORTANT MECHANISM FOR THE INACTIVATION OF TUMOR-RELATED GENES IN HUMAN TUMORS. GASTRIC MUCOSA-ASSOCIATED LYMPHOID TISSUE (MALT) LYMPHOMAS ARISE FROM HELICOBACTER PYLORI-ASSOCIATED CHRONIC GASTRITIS; MOST PATIENTS ARE H. PYLORI-POSITIVE AND ERADICATION THERAPY IS HIGHLY EFFECTIVE. IN THE PRESENT STUDY, WE USED METHYLATION-SPECIFIC PCR TO ANALYZE THE DNA METHYLATION STATUS OF 11 TUMOR-RELATED GENES (KIP2, P16, HMLH-1, P15, P73, MGMT, DAPK, MINT1, MINT2, MINT31 AND HCAD) IN 21 SPECIMENS OF MALT LYMPHOMA, 5 SPECIMENS OF MALT LYMPHOMA WITH LARGE CELL COMPONENT (HIGH-GRADE MALT LYMPHOMA), 15 SPECIMENS OF DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL), 8 SPECIMENS OF COMPLETE REMISSION OF MALT LYMPHOMA AFTER ERADICATION THERAPY, 5 SPECIMENS WITH NO EVIDENCE OF MALIGNANCY AND PBMCS FROM 10 HEALTHY DONORS. THE AVERAGE NUMBER OF METHYLATED GENES WAS SIGNIFICANTLY GREATER IN GASTRIC LYMPHOMAS AS COMPARED TO NORMAL CONTROLS (P<0.001). THE CPG ISLAND METHYLATOR PHENOTYPE (CIMP) WAS OBSERVED IN 93.3% (14/15) OF DLBCLS, 100% (5/5) OF HIGH-GRADE MALT LYMPHOMAS AND 61.9% (13/21) OF MALT LYMPHOMAS; IN CONTRAST, CIMP WAS NOT FOUND IN THE CONTROL GROUP (0%). THE AVERAGE NUMBER OF METHYLATED GENES AND THE CIMP INCIDENCE SIGNIFICANTLY INCREASED WITH H. PYLORI INFECTION. FURTHERMORE, ABERRANT CPG METHYLATION OF SPECIFIC GENES, SUCH AS P16, MGMT AND MINT31, WAS CONSISTENTLY ASSOCIATED WITH H. PYLORI INFECTION. THESE FINDINGS STRONGLY SUGGEST THAT H. PYLORI INFECTION CAUSES THE ABERRANT DNA HYPERMETHYLATION OF SPECIFIC GENES AND INDUCES CIMP, WHICH IS AN IMPORTANT EPIGENETIC MECHANISM FOR THE DEVELOPMENT AND PROGRESSION OF GASTRIC MALT LYMPHOMA; ADDITIONALLY, OUR FINDINGS PROVIDE NEW EPIGENETIC MARKERS. 2009 5 152 19 ABERRANT METHYLATION OF DAPK IN LONG-STANDING ULCERATIVE COLITIS AND ULCERATIVE COLITIS-ASSOCIATED CARCINOMA. DEATH-ASSOCIATED PROTEIN KINASE (DAPK) HAS PRO-APOPTOTIC FUNCTIONS AND PARTICIPATES IN VARIOUS APOPTOTIC SYSTEMS. DAPK ACTS AS A TUMOR SUPPRESSOR, AND ITS INACTIVATION BY PROMOTER HYPERMETHYLATION HAS BEEN FREQUENTLY OBSERVED IN VARIOUS HUMAN CANCERS. AS ALTERATIONS OF PRO-APOPTOTIC GENES MIGHT CAUSE INSTABILITY IN THE BALANCE OF CELL-TURNOVER DURING CHRONIC INFLAMMATORY PROCESSES, EPIGENETIC SILENCING OF DAPK MIGHT BE INVOLVED IN THE CARCINOGENESIS OF ULCERATIVE COLITIS-ASSOCIATED CARCINOMA (UCC). TO EVALUATE THE ROLE OF DAPK IN THE INFLAMMATION-DRIVEN CARCINOGENESIS OF ULCERATIVE COLITIS (UC), WE ANALYZED PROMOTER HYPERMETHYLATION AND PROTEIN EXPRESSION OF DAPK USING METHYLATION-SPECIFIC PCR AND IMMUNOHISTOCHEMISTRY IN 43 UCCS AND PAIRED UC-BACKGROUND MUCOSA, AS WELL AS IN UC-BACKGROUND MUCOSA OF 50 PATIENTS WITHOUT UCC. THE FREQUENCY OF METHYLATION OF DAPK IN UCCS WAS LOW (27.6%) COMPARED TO OVERALL NON-NEOPLASTIC UC-BACKGROUND MUCOSA (48.3%; P=0.02) AND SPORADIC COLORECTAL CARCINOMA (57.4%, P=0.019). THE DIFFERENCE IN THE METHYLATION FREQUENCY IN UC-BACKGROUND MUCOSA IN PATIENTS WITHOUT UCC (54.2%), COMPARED TO THOSE WITH UCC (40.0%), WAS NOT SIGNIFICANT (P=0.141). PROMOTER METHYLATION CORRELATED SIGNIFICANTLY WITH DECREASED DAPK PROTEIN EXPRESSION (P<0.001) AND SEVERITY OF INFLAMMATORY ACTIVITY (P=0.024). IN UNMETHYLATED UC-BACKGROUND MUCOSA, DAPK PROTEIN EXPRESSION INCREASED WITH ACTIVITY OF UC-ASSOCIATED INFLAMMATION, SUGGESTING A PROTECTIVE ROLE OF THE PRO-APOPTOTIC DAPK DURING THE CHRONIC INFLAMMATORY PROCESS OF UC. THUS, INACTIVATION OF DAPK BY PROMOTER HYPERMETHYLATION MIGHT BE CRUCIAL FOR ACCUMULATION OF DNA DAMAGE IN INFLAMED MUCOSA OF UC, AND MIGHT THEREFORE CONTRIBUTE TO THE INITIATION OF THE NEOPLASTIC PROCESS AND DEVELOPMENT OF UC-ASSOCIATED CARCINOMA. 2010 6 2133 14 EPIGENETIC INACTIVATION OF THE MIR-34A IN HEMATOLOGICAL MALIGNANCIES. MIR-34A IS A TRANSCRIPTIONAL TARGET OF P53 AND IMPLICATED IN CARCINOGENESIS. WE STUDIED THE ROLE OF MIR-34A METHYLATION IN A PANEL OF HEMATOLOGICAL MALIGNANCIES INCLUDING ACUTE LEUKEMIA [ACUTE MYELOID LEUKEMIA (AML) AND ACUTE LYMPHOBLASTIC LEUKEMIA (ALL)], CHRONIC LEUKEMIA [CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) AND CHRONIC MYELOID LEUKEMIA (CML)], MULTIPLE MYELOMA (MM) AND NON-HODGKIN'S LYMPHOMA (NHL). THE METHYLATION STATUS OF MIR-34A PROMOTER WAS STUDIED IN 12 CELL LINES AND 188 DIAGNOSTIC SAMPLES BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION. MIR-34A PROMOTER WAS UNMETHYLATED IN NORMAL CONTROLS BUT METHYLATED IN 75% LYMPHOMA AND 37% MYELOMA CELL LINES. HYPOMETHYLATING TREATMENT LED TO RE-EXPRESSION OF PRI-MIR-34A TRANSCRIPT IN LYMPHOMA CELLS WITH HOMOZYGOUS MIR-34A METHYLATION. IN PRIMARY SAMPLES AT DIAGNOSIS, MIR-34A METHYLATION WAS DETECTED IN 4% CLL, 5.5% MM SAMPLES AND 18.8% OF NHL AT DIAGNOSIS BUT NONE OF ALL, AML AND CML (P = 0.011). IN MM PATIENTS WITH PAIRED SAMPLES, MIR-34A METHYLATION STATUS REMAINED UNCHANGED AT PROGRESSION. AMONGST LYMPHOID MALIGNANCIES, MIR-34A WAS PREFERENTIALLY METHYLATED IN NHL (P = 0.018), IN PARTICULAR NATURAL KILLER (NK)/T-CELL LYMPHOMA. IN CONCLUSION, AMONGST HEMATOLOGICAL MALIGNANCIES, MIR-34A METHYLATION IS PREFERENTIALLY HYPERMETHYLATED IN NHL, IN PARTICULAR NK/T-CELL LYMPHOMA, IN A TUMOR-SPECIFIC MANNER, THEREFORE THE ROLE OF MIR-34A IN LYMPHOMAGENESIS WARRANTS FURTHER STUDY. 2010 7 4246 24 METHYLATION STATUS OF THE T-CADHERIN GENE PROMOTOR IN PERIPHERAL BLOOD MONONUCLEAR CELLS IS ASSOCIATED WITH HBV-RELATED HEPATOCELLULAR CARCINOMA PROGRESSION. DNA METHYLATION IS ONE OF THE EPIGENETIC MECHANISMS TO REGULATE GENE EXPRESSION AND FREQUENTLY OCCURS IN HUMAN CANCER CELLS. T-CADHERIN (CDH13) IS A NEW MEMBER OF THE CADHERIN SUPERFAMILY AND POSSESSES MULTIPLE FUNCTIONS. OUR STUDY INCLUDED 26 NORMAL CONTROLS (NCS), 65 CHRONIC HEPATITIS B PATIENTS (CHB), 14 LIVER CIRRHOSIS PATIENTS (LC) AND 157 HEPATOCELLULAR CARCINOMA PATIENTS (HCC). WE MAINLY FOCUSED ON THE MRNA EXPRESSION AND METHYLATION STATUS OF CDH13 IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS), WHICH WERE DETECTED BY SEMI-QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION (RT-QPCR) AND METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) RESPECTIVELY. THE CDH13 MRNA LEVEL WAS LOWER IN HCC, ESPECIALLY IN EARLY-STAGE OF HCC THAN IN NCS AND CHB GROUPS (P < 0.05). METHYLATION FREQUENCY OF THE CDH13 PROMOTER WAS SIGNIFICANTLY HIGHER IN HCC PATIENTS THAN IN THE NCS AND CHB GROUPS (67.52 % VS 0.00 %, P < 0.001, 67.52 % VS 52.31 %, P < 0.05, RESPECTIVELY). CDH13 MRNA LEVEL WAS SIGNIFICANTLY AND RELATIVELY LOWER IN METHYLATED GROUPS THAN IN UNMETHYLATED GROUPS AMONG THE WHOLE PARTICIPANTS. THE METHYLATION LEVEL OF CDH13 PROMOTER IN HCC MIGHT BE INFLUENCED OR PARTLY INFLUENCED BY SOME CRITICAL FACTORS SUCH AS TBIL, ALB AND AFP (P < 0.05). AS AN IMPORTANT FACTOR IN SIGNALING PATHWAY REGULATING BY CDH13 TO PROMOTE CARCINOGENESIS, JNK LEVEL WAS SIGNIFICANTLY HIGHER IN HCC WHICH HAD A HIGHER METHYLATION FREQUENCY THAN IN NCS, CHB AND LC (P < 0.05). FURTHERMORE, THE COMBINATION OF THE METHYLATED CDH13 LEVEL AND AFP LEVEL SHOWED A BETTER SCORE: AUC = 0.796 (SE = 0.031, 95 %CI 0.735-0.857; P < 0.001) IN MALE AND AUC = 0.832 (SE = 0.057, 95 %CI 0.721-0.944; P < 0.001) IN FEMALE COMPARED TO AFP ALONE FOR DIAGNOSING HCC FROM NCS, CHB AND LC. THE METHYLATION OF CDH13 PROMOTER WAS AN INDEPENDENT PREDICTOR FOR ASSESSING THE PROGNOSIS OF HCC PATIENTS (R=-1.378 P < 0.05). IN CONCLUSION, HYPERMETHYLATION OF CDH13 IN PBMCS WAS ASSOCIATED WITH THE UNDEREXPRESSION OF MRNA AND THE HIGH RISK OF HCC. THE METHYLATION STATUS OF THE CDH13 PROMOTER IN PBMCS WAS A POTENTIAL NONINVASIVE BIOMARKER TO PREDICT THE PROGNOSIS OF HCC PATIENTS. 2020 8 3071 27 GENOME-WIDE DNA METHYLATION PROFILING INTEGRATED WITH GENE EXPRESSION PROFILING IDENTIFIES PAX9 AS A NOVEL PROGNOSTIC MARKER IN CHRONIC LYMPHOCYTIC LEUKEMIA. BACKGROUND: IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), EPIGENOMIC AND GENOMIC STUDIES HAVE EXPANDED THE EXISTING KNOWLEDGE ABOUT THE DISEASE BIOLOGY AND LED TO THE IDENTIFICATION OF POTENTIAL BIOMARKERS RELEVANT FOR IMPLEMENTATION OF PERSONALIZED MEDICINE. IN THIS STUDY, AN ATTEMPT HAS BEEN MADE TO EXAMINE AND INTEGRATE THE GLOBAL DNA METHYLATION CHANGES WITH GENE EXPRESSION PROFILE AND THEIR IMPACT ON CLINICAL OUTCOME IN EARLY STAGE CLL PATIENTS. RESULTS: THE INTEGRATION OF DNA METHYLATION PROFILE (N = 14) WITH THE GENE EXPRESSION PROFILE (N = 21) REVEALED 142 GENES AS HYPERMETHYLATED-DOWNREGULATED AND; 62 GENES AS HYPOMETHYLATED-UPREGULATED IN EARLY STAGE CLL PATIENTS COMPARED TO CD19+ B-CELLS FROM HEALTHY INDIVIDUALS. THE MRNA EXPRESSION LEVELS OF 17 GENES IDENTIFIED TO BE DIFFERENTIALLY METHYLATED AND/OR DIFFERENTIALLY EXPRESSED WAS FURTHER EXAMINED IN EARLY STAGE CLL PATIENTS (N = 93) BY QUANTITATIVE REAL TIME PCR (RQ-PCR). SIGNIFICANT DIFFERENCES WERE OBSERVED IN THE MRNA EXPRESSION OF MEIS1, PMEPA1, SOX7, SPRY1, CDK6, TBX2, AND SPRY2 GENES IN CLL CELLS AS COMPARED TO B-CELLS FROM HEALTHY INDIVIDUALS. THE ANALYSIS IN THE IGHV MUTATION BASED CATEGORIES (UNMUTATED = 39, MUTATED = 54) REVEALED SIGNIFICANTLY HIGHER MRNA EXPRESSION OF CRY1 AND PAX9 GENES IN THE IGHV UNMUTATED SUBGROUP (P < 0.001). THE RELATIVE RISK OF TREATMENT INITIATION WAS SIGNIFICANTLY HIGHER AMONG PATIENTS WITH HIGH EXPRESSION OF CRY1 (RR = 1.91, P = 0.005) OR PAX9 (RR = 1.87, P = 0.001). HIGH EXPRESSION OF CRY1 (HR: 3.53, P < 0.001) OR PAX9 (HR: 3.14, P < 0.001) GENE WAS SIGNIFICANTLY ASSOCIATED WITH SHORTER TIME TO FIRST TREATMENT. THE HIGH EXPRESSION OF PAX9 GENE (HR: 3.29, 95% CI 1.172-9.272, P = 0.016) WAS ALSO PREDICTIVE OF SHORTER OVERALL SURVIVAL IN CLL. CONCLUSIONS: THE DNA METHYLATION CHANGES ASSOCIATED WITH MRNA EXPRESSION OF CRY1 AND PAX9 GENES ALLOW RISK STRATIFICATION OF EARLY STAGE CLL PATIENTS. THIS COMPREHENSIVE ANALYSIS SUPPORTS THE CONCEPT THAT THE EPIGENETIC CHANGES ALONG WITH THE ALTERED EXPRESSION OF GENES HAVE THE POTENTIAL TO PREDICT CLINICAL OUTCOME IN EARLY STAGE CLL PATIENTS. 2017 9 1424 21 DIFFERENTIAL DNA METHYLATION OF GENE PROMOTERS IN SMALL B-CELL LYMPHOMAS. IMPROVED CARE OF PATIENTS WITH SMALL B-CELL LYMPHOMAS (SBCLS) IS LIKELY TO RESULT FROM THE ONGOING DISCOVERY OF MOLECULAR MARKERS THAT BETTER DEFINE THESE MALIGNANT NEOPLASMS. WE IDENTIFIED MULTIPLE GENE LOCI WHOSE DNA METHYLATION PATTERNS DIFFERED BETWEEN 3 TYPES OF SBCL: B-CELL CHRONIC LYMPHOCYTIC LEUKEMIA/SMALL LYMPHOCYTIC LYMPHOMA, MANTLE CELL LYMPHOMA, AND GRADES I AND II FOLLICULAR LYMPHOMA. THIS ANALYSIS WAS PERFORMED USING AN OLIGONUCLEOTIDE MICROARRAY THAT ALLOWED DETERMINATION OF THE DNA METHYLATION STATUS OF 156 LOCI IN 38 GENES. COMBINED BISULFITE RESTRICTION ANALYSIS AND METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION WERE USED TO VALIDATE THE DIFFERENTIAL METHYLATION OF 6 OF THESE GENES. BY USING NON-HODGKIN LYMPHOMA CELL LINES AS MODELS, THESE GENES WERE EXAMINED FURTHER FOR METHYLATION AND GENE EXPRESSION RELATIONSHIPS. THIS STUDY ILLUSTRATES NONRANDOM EPIGENETIC ALTERATIONS IN SBCLS THAT SEEM TO PREFERENTIALLY INVOLVE LYMPHOMAS OF GERMINAL CENTER DERIVATION. 2005 10 2843 20 FREQUENT CPG ISLAND METHYLATION IN PRECURSOR LESIONS AND EARLY GASTRIC ADENOCARCINOMAS. GASTRIC CARCINOGENESIS INVOLVES MULTIPLE GENETIC AND EPIGENETIC ALTERATIONS. EPIGENETIC SILENCING OF TUMOR-RELATED GENES DUE TO CPG ISLAND METHYLATION (CIM) HAS BEEN RECENTLY REPORTED IN GASTRIC CANCER, BUT THE ROLE IN PRECURSOR LESIONS IS NOT WELL UNDERSTOOD. WE ANALYSED THE METHYLATION STATUS OF THE TUMOR SUPPRESSOR GENE P16, THE DNA MISMATCH REPAIR GENE HMLH1, AND FOUR CPG ISLANDS (MINT1, MINT2, MINT25, AND MINT31) USING METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION IN 35 POLYPOID ADENOMAS AND 46 FLAT DYSPLASIAS UNASSOCIATED WITH CARCINOMA, 34 EARLY ADENOCARCINOMAS (T1N0M0) AND ASSOCIATED ADENOMAS/DYSPLASIAS, AND CORRESPONDING ADJACENT NON-NEOPLASTIC MUCOSA. THE EXTENT OF CIM WAS DEFINED BY THE FRACTION OF METHYLATED LOCI (METHYLATION INDEX), AND COMPARED WITH PREVIOUSLY CHARACTERIZED GENETIC ALTERATIONS (MICROSATELLITE INSTABILITY (MSI) AND APC GENE MUTATION). WE FOUND THAT METHYLATION OF P16 WAS MORE FREQUENT IN ADENOCARCINOMA-ASSOCIATED DYSPLASIAS/ADENOMAS (29%) AND ADENOCARCINOMAS (44%) AS COMPARED TO FLAT DYSPLASIAS (4%) AND ADENOMAS (18%) UNASSOCIATED WITH ADENOCARCINOMA (P=0.001). THE MEAN METHYLATION INDEX INCREASED FROM NORMAL/CHRONIC GASTRITIS (CG) MUCOSA (0.09) TO INTESTINAL METAPLASIA (IM) (0.16), FLAT DYSPLASIAS (0.40) OR POLYPOID ADENOMAS (0.41) UNASSOCIATED WITH CARCINOMA, DYSPLASIAS/ADENOMAS ASSOCIATED WITH CARCINOMA (0.44), AND ADENOCARCINOMAS (0.44). THERE WAS NO DIFFERENCE IN FREQUENCIES OF HIGH-LEVEL CPG ISLAND METHYLATION (CIM-H, METHYLATION INDEX > OR =0.5) AMONG FLAT DYSPLASIAS (50%) AND POLYPOID ADENOMAS (51%) UNASSOCIATED WITH CARCINOMA, DYSPLASIAS/ADENOMAS ASSOCIATED WITH ADENOCARCINOMA (47%), AND ADENOCARCINOMA (47%). CIM-H WAS PRESENT IN 15% OF IM, BUT NOT IN NORMAL/CG MUCOSA. THERE WAS A SIGNIFICANT CORRELATION BETWEEN METHYLATION OF HMLH1 AND HIGH-LEVEL OF MICROSATELLITE INSTABILITY (MSI-H): METHYLATION OF HMLH1 WAS PRESENT IN 71% OF MSI-H TUMORS, BUT ONLY 8% OF MSI-LOW TUMORS AND 13% OF MICROSATELLITE-STABLE TUMORS (P=0.0001). THERE WAS NO STATISTICAL DIFFERENCE BETWEEN METHYLATION INDEX AND APC MUTATION. OUR RESULTS INDICATE THAT CONCURRENT PROMOTER METHYLATION IS AN EARLY AND FREQUENT EVENT IN GASTRIC TUMORIGENESIS, INCLUDING BOTH MSI-H AND MICROSATELLITE-STABLE NEOPLASMS. METHYLATION OF THE P16 GENE MAY CONTRIBUTE TO THE MALIGNANT TRANSFORMATION OF GASTRIC PRECURSOR LESIONS. 2004 11 4432 20 MOLECULAR CHARACTERIZATION OF RICHTER SYNDROME IDENTIFIES DE NOVO DIFFUSE LARGE B-CELL LYMPHOMAS WITH POOR PROGNOSIS. RICHTER SYNDROME (RS) IS THE TRANSFORMATION OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) INTO AGGRESSIVE LYMPHOMA, MOST COMMONLY DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL). WE CHARACTERIZE 58 PRIMARY HUMAN RS SAMPLES BY GENOME-WIDE DNA METHYLATION AND WHOLE-TRANSCRIPTOME PROFILING. OUR COMPREHENSIVE APPROACH DETERMINES RS DNA METHYLATION PROFILE AND UNRAVELS A CLL EPIGENETIC IMPRINT, ALLOWING CLL-RS CLONAL RELATIONSHIP ASSESSMENT WITHOUT THE NEED OF THE INITIAL CLL TUMOR DNA. DNA METHYLATION- AND TRANSCRIPTOMIC-BASED CLASSIFIERS WERE DEVELOPED, AND TESTING ON LANDMARK DLBCL DATASETS IDENTIFIES A POOR-PROGNOSIS, ACTIVATED B-CELL-LIKE DLBCL SUBSET IN 111/1772 SAMPLES. THE CLASSIFICATION ROBUSTLY IDENTIFIES PHENOTYPES VERY SIMILAR TO RS WITH A SPECIFIC GENOMIC PROFILE, ACCOUNTING FOR 4.3-8.3% OF DE NOVO DLBCLS. IN THIS WORK, RS MULTI-OMICS CHARACTERIZATION DETERMINES ONCOGENIC MECHANISMS, ESTABLISHES A SURROGATE MARKER FOR CLL-RS CLONAL RELATIONSHIP, AND PROVIDES A CLINICALLY RELEVANT CLASSIFIER FOR A SUBSET OF PRIMARY "RS-TYPE DLBCL" WITH UNFAVORABLE PROGNOSIS. 2023 12 6871 18 [PATHOGENETIC IMPORTANCE OF HELICOBACTER PYLORI INFECTION]. H. PYLORI ARE ETIOLOGICAL FACTOR OF HUMAN ACUTE AND CHRONIC GASTRITIS. DEPENDING ON PATHOGENIC FACTORS OF MICROORGANISM AND POLYMORPHISM OF HUMAN GENES, CHRONIC GASTRITIS CAN BE A CAUSE FOR ULCERATIVE ENTERITIS OF THE DUODENUM OR STOMACH, GASTRIC ADENOCARCINOMA AND MALT-LYMPHOMA DEVELOPMENT. WE REVEALED GENETIC FEATURES OF BACTERIA, DETERMINED THE INTENSITY OF INFLAMMATION, SUCH AS PATHOGENIC FACTORS--CAG, PLASTIC REGION OF THE GENOME AND ADHESIN CODING GENES. EPIGENETIC CHANGES, FOR EXAMPLE THE METHYLATION OF E-CADHERIN GENE ASSOCIATED WITH H PYLORI, ARE CRUCIAL FOR CARCINOGENESIS. THEREBY, PREDISPOSITION OF CHRONIC GASTRITIS ASSOCIATED WITH H. PYLORI TO ULCERATIVE ENTERITIS OF THE DUODENUM, ULCERATIVE STOMACH DISEASE OR GASTRIC ADENOCARCINOMA DEPENDS ON TOPOGRAPHY, THE INTENSITY OF INFLAMMATION AND CHANGES OF ACID PRODUCTION IN THE STOMACH. 2012 13 2131 18 EPIGENETIC INACTIVATION OF THE HSA-MIR-203 IN HAEMATOLOGICAL MALIGNANCIES. MIR-203 IS A TUMOUR SUPPRESSOR MICRORNA (MIRNA). WE STUDIED THE METHYLATION OF HSA-MIR-203 IN 150 SAMPLES INCLUDING ACUTE MYELOID LEUKAEMIA (AML), ACUTE LYMPHOBLASTIC LEUKAEMIA (ALL), CHRONIC MYELOID LEUKAEMIA (CML), CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL) AND NON-HODGKIN'S LYMPHOMA (NHL) BY METHYLATION-SPECIFIC PCR, AND MIRNA EXPRESSION BY STEM-LOOP RT-QPCR. HSA-MIR-203 PROMOTER WAS UNMETHYLATED IN NORMAL CONTROLS BUT HOMOZYGOUSLY METHYLATED IN TWO AML AND FOUR LYMPHOMA CELL LINES, IN WHICH 5-AZA-2'-DEOXYCYTIDINE TREATMENT LED TO PROMOTER DEMETHYLATION AND MIR-203 RE-EXPRESSION. RESTORATION OF MIR-203 EXPRESSION IN LYMPHOMA CELLS INHIBITED CELLULAR PROLIFERATION AND INCREASED CELL DEATH, SUGGESTING AN INHERENT TUMOUR SUPPRESSOR ACTIVITY. IN PRIMARY SAMPLES, HSA-MIR-203 METHYLATION WAS ABSENT IN CML BUT DETECTED IN 5.0% ALL, 10.0% AML, 42.0% CLL AND 38.8% OF NHL (INCLUDING SIX [60.0%] NATURAL KILLER-CELL, NINE [40.9%] B-CELL AND FOUR [23.5%] T CELL NHL). MOREOVER, HSA-MIR-203 METHYLATION WAS ASSOCIATED WITH HYPERMETHYLATION OF HSA-MIR-34A, -124A AND -196B IN NHL BUT NOT CLL. IN CLL, HSA-MIR-203 METHYLATION WAS ASSOCIATED WITH A HIGHER PRESENTING HB LEVEL (P = 0.033). THE PROJECTED 10 YEAR OVERALL SURVIVAL OF THE CLL PATIENTS WAS 58.2%, WHICH WAS IMPACTED BY RAI STAGE AND HIGH-RISK KARYOTYPES BUT NOT HSA-MIR-203 METHYLATION. HSA-MIR-203 WAS MORE FREQUENTLY METHYLATED IN LYMPHOID THAN MYELOID MALIGNANCIES (P = 0.002). IN CONCLUSION, MIR-203, A TUMOUR SUPPRESSOR GENE, WAS HYPERMETHYLATED IN A TUMOUR-SPECIFIC MANNER WITH GENE SILENCING. HSA-MIR-203 WAS MORE FREQUENTLY HYPERMETHYLATED IN LYMPHOID THAN MYELOID MALIGNANCIES. IN NHL, HSA-MIR-203 METHYLATION WAS ASSOCIATED WITH CONCOMITANT METHYLATION OF OTHER TUMOUR SUPPRESSOR MIRNAS. THE FREQUENT HSA-MIR-203 METHYLATION IN LYMPHOID MALIGNANCIES SUGGESTED A PATHOGENETIC ROLE OF HSA-MIR-203 METHYLATION. 2011 14 3444 25 HYPERMETHYLATION OF E-CADHERIN IN LEUKEMIA. E-CADHERIN GENE IS OFTEN TERMED A "METASTASIS SUPPRESSOR" GENE BECAUSE THE E-CADHERIN PROTEIN CAN SUPPRESS TUMOR CELL INVASION AND METASTASIS. INACTIVATION OF THE E-CADHERIN GENE OCCURS IN UNDIFFERENTIATED SOLID TUMORS BY BOTH GENETIC AND EPIGENETIC MECHANISMS; HOWEVER, THE ROLE OF E-CADHERIN IN HEMATOLOGIC MALIGNANCIES IS ONLY NOW BEING RECOGNIZED. E-CADHERIN EXPRESSION IS ESSENTIAL FOR ERYTHROBLAST AND NORMOBLAST MATURATION, YET EXPRESSION IS REDUCED OR ABSENT IN LEUKEMIC BLAST CELLS. THIS STUDY EXAMINED THE MESSENGER RNA (MRNA) AND PROTEIN EXPRESSION OF THE E-CADHERIN GENE IN BONE MARROW AND BLOOD SAMPLES FROM NORMAL DONORS AND PATIENTS WITH LEUKEMIA. WE FOUND THAT ALL NORMAL DONOR SAMPLES EXPRESSED E-CADHERIN MRNA, WHEREAS BOTH SAMPLES OF ACUTE MYELOGENOUS LEUKEMIA AND CHRONIC LYMPHOCYTIC LEUKEMIA HAD A SIGNIFICANT REDUCTION OR ABSENCE OF EXPRESSION. HOWEVER, NORMAL BLAST COUNTERPARTS EXPRESSED ONLY A LOW LEVEL OF E-CADHERIN SURFACE PROTEIN. SODIUM BISULPHITE GENOMIC SEQUENCING WAS USED TO FULLY CHARACTERIZE THE METHYLATION PATTERNS OF THE CPG ISLAND ASSOCIATED WITH THE E-CADHERIN GENE PROMOTER IN THOSE SAMPLES WITH MATCHED DNA. ALL OF THE NORMAL CONTROL SAMPLES WERE ESSENTIALLY UNMETHYLATED; HOWEVER, 14 OF 18 (78%) OF THE LEUKEMIA SAMPLES HAD ABNORMAL HYPERMETHYLATION OF THE E-CADHERIN CPG ISLAND. IN FACT BOTH ALLELES OF THE E-CADHERIN GENE WERE OFTEN HYPERMETHYLATED. WE CONCLUDE THE E-CADHERIN GENE IS A COMMON TARGET FOR HYPERMETHYLATION IN HEMATOLOGIC MALIGNANCIES. 2000 15 5989 24 TGF-BETA/SMAD PATHWAY IS MODULATED BY MIR-26B-5P: ANOTHER PIECE IN THE PUZZLE OF CHRONIC LYMPHOCYTIC LEUKEMIA PROGRESSION. CLINICAL AND MOLECULAR HETEROGENEITY ARE HALLMARKS OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), A NEOPLASM CHARACTERIZED BY ACCUMULATION OF MATURE AND CLONAL LONG-LIVED CD5 + B-LYMPHOCYTES. MUTATIONAL STATUS OF THE IGHV GENE OF LEUKEMIC CLONES IS A POWERFUL PROGNOSTIC TOOL IN CLL, AND IT IS WELL ESTABLISHED THAT UNMUTATED CLLS (U-CLLS) HAVE WORSE EVOLUTION THAN MUTATED CASES. NEVERTHELESS, PROGRESSION AND TREATMENT REQUIREMENT OF PATIENTS CAN EVOLVE INDEPENDENTLY FROM THE MUTATIONAL STATUS. MICROENVIRONMENT SIGNALING OR EPIGENETIC CHANGES PARTIALLY EXPLAIN THIS DIFFERENT BEHAVIOR. THUS, WE THINK THAT DETAILED CHARACTERIZATION OF THE MIRNAS LANDSCAPE FROM PATIENTS WITH DIFFERENT CLINICAL EVOLUTION COULD FACILITATE THE UNDERSTANDING OF THIS HETEROGENEITY. SINCE MIRNAS ARE KEY PLAYERS IN LEUKEMIA PATHOGENESIS AND EVOLUTION, WE AIM TO BETTER CHARACTERIZE DIFFERENT CLL BEHAVIORS BY COMPARING THE MIRNOME OF CLINICALLY PROGRESSIVE U-CLLS VS. STABLE U-CLLS. OUR DATA SHOW UP-REGULATION OF MIR-26B-5P, MIR-106B-5P, AND MIR-142-5P IN PROGRESSIVE CASES AND INDICATE A KEY ROLE FOR MIR-26B-5P DURING CLL PROGRESSION. SPECIFICALLY, UP-REGULATION OF MIR-26B-5P IN CLL CELLS BLOCKS TGF-BETA/SMAD PATHWAY BY DOWN-MODULATION OF SMAD-4, RESULTING IN LOWER EXPRESSION OF P21(-CIP1) KINASE INHIBITOR AND HIGHER EXPRESSION OF C-MYC ONCOGENE. THIS WORK DESCRIBES A NEW MOLECULAR MECHANISM LINKING CLL PROGRESSION WITH TGF-BETA MODULATION AND PROPOSES AN ALTERNATIVE STRATEGY TO EXPLORE IN CLL THERAPY. 2022 16 1658 26 DOWN-REGULATION OF A PRO-APOPTOTIC PATHWAY REGULATED BY PCAF/ADA3 IN EARLY STAGE GASTRIC CANCER. THE LOSS OF P300/CBP-ASSOCIATED PROTEIN (PCAF) EXPRESSION IS ASSOCIATED WITH POOR CLINICAL OUTCOME IN GASTRIC CANCER, AND A POTENTIAL BIO-MARKER FOR INVASIVE AND AGGRESSIVE TUMORS. HOWEVER, THE MECHANISM LINKING LOSS OF PCAF TO THE ONSET OF GASTRIC CANCER HAS NOT BEEN IDENTIFIED. GIVEN THAT PCAF AND ITS BINDING PARTNER TRANSCRIPTIONAL ADAPTOR PROTEIN 3 (ADA3) WERE RECENTLY SHOWN TO REGULATE THE INTRINSIC (MITOCHONDRIAL) PATHWAY TO APOPTOSIS VIA EPIGENETIC REGULATION OF PHOSPHOFURIN ACIDIC CLUSTER SORTING PROTEINS 1 AND 2 (PACS1, PACS2), WE ANALYZED PCAF, ADA3, AND PACS1/2 EXPRESSION IN 99 PATIENT-MATCHED SURGICAL SAMPLES RANGING FROM NORMAL GASTRIC MUCOSA, THROUGH PRE-MALIGNANT CHRONIC GASTRITIS AND INTESTINAL METAPLASIA TO STAGE I-III INVASIVE CANCERS. PCAF MRNA LEVELS WERE NOT REDUCED IN EITHER PRE-MALIGNANT STATE BUT WERE SIGNIFICANTLY DOWN-REGULATED IN ALL STAGES OF GASTRIC CANCER, COMMENCING AT AJCC STAGE I (P < 0.05), THUS LINKING REDUCED PCAF EXPRESSION WITH EARLY MALIGNANT CHANGE. FURTHERMORE, PATIENTS WITH COMBINED REDUCTION OF PCAF AND PACS1 HAD SIGNIFICANTLY POORER OVERALL SURVIVAL (P = 0.0257), CONFIRMED IN AN INDEPENDENT DATASET OF 359 PATIENTS (P = 5.8 X 10E-6). AT THE PROTEIN LEVEL, PCAF, ADA3, AND PACS1 EXPRESSION WERE ALL SIGNIFICANTLY DOWN-REGULATED IN INTESTINAL-TYPE GASTRIC CANCER, AND CORRELATED WITH REDUCED PROGRESSION FREE SURVIVAL. WE CONCLUDE THAT A PRO-APOPTOTIC MECHANISM CENTERED ON THE INTRINSIC (MITOCHONDRIAL) PATHWAY AND REGULATED BY PCAF/ADA3 CAN INFLUENCE THE PROGRESSION FROM PREMALIGNANT TO MALIGNANT CHANGE, AND THUS ACT AS A TUMOR SUPPRESSION MECHANISM IN GASTRIC CANCER. 2018 17 1830 20 EFFECTS OF LONG-TERM ASPIRIN USE ON MOLECULAR ALTERATIONS IN PRECANCEROUS GASTRIC MUCOSA IN PATIENTS WITH AND WITHOUT GASTRIC CANCER. THE RISK OF GASTRIC CANCER (GC) REMAINS EVEN AFTER H. PYLORI ERADICATION; THUS, OTHER COMBINATION TREATMENTS, SUCH AS CHEMOPREVENTIVE DRUGS, ARE NEEDED. WE EVALUATED THE EFFECTS OF ASPIRIN ON GENETIC/EPIGENETIC ALTERATIONS IN PRECANCEROUS CONDITIONS, I.E., ATROPHIC MUCOSA (AM) AND INTESTINAL METAPLASIA (IM), IN PATIENTS WITH CHRONIC GASTRITIS WHO HAD TAKEN ASPIRIN FOR MORE THAN 3 YEARS. A TOTAL OF 221 BIOPSY SPECIMENS FROM 74 PATIENTS, INCLUDING ATROPHIC GASTRITIS (AG) CASES WITHOUT ASPIRIN USE (CONTROL), AG CASES WITH ASPIRIN USE (AG GROUP), AND GC CASES WITH ASPIRIN USE (GC GROUP), WERE ANALYZED. ASPIRIN USE WAS ASSOCIATED WITH A SIGNIFICANT REDUCTION OF CDH1 METHYLATION IN AM (OR: 0.15, 95% CI: 0.06-0.41, P = 0.0002), BUT WAS LESS EFFECTIVE IN REVERSING THE METHYLATION THAT OCCURRED IN IM. FREQUENT HYPERMETHYLATION INCLUDING THAT OF CDH1 IN AM INCREASED IN THE GC GROUP COMPARED TO THE AG GROUP, AND CDH1 METHYLATION WAS AN INDEPENDENT PREDICTIVE MARKER OF GC (OR: 8.50, 95% CI: 2.64-25.33, P = 0.0003). IN PATIENTS WITH LONG-TERM ASPIRIN USE, THE CHANGES OF MOLECULAR EVENTS IN AM BUT NOT IM MAY BE AN IMPORTANT FACTOR IN THE REDUCTION OF CANCER INCIDENCE. IN ADDITION, METHYLATION OF THE CDH1 GENE IN AM MAY BE A SURROGATE OF GC. 2017 18 4237 26 METHYLATION PATTERN OF THBS1, GATA-4, AND HIC1 IN PEDIATRIC AND ADULT PATIENTS INFECTED WITH HELICOBACTER PYLORI. BACKGROUND: HELICOBACTER PYLORI INFECTION IS USUALLY ACQUIRED IN CHILDHOOD AND PERSISTS INTO ADULTHOOD IF UNTREATED. THE BACTERIUM INDUCES A CHRONIC INFLAMMATORY RESPONSE, WHICH IS ASSOCIATED WITH EPIGENETIC ALTERATIONS IN ONCOGENES, TUMOR-SUPPRESSOR GENES, CELL-CYCLE REGULATORS, AND CELL-ADHESION MOLECULES. AIM: THE AIM OF THIS STUDY WAS TO ANALYZE THE EFFECT OF H. PYLORI INFECTION ON THE METHYLATION STATUS OF THROMBOSPONDIN-1 (THBS1), HYPERMETHYLATED IN CANCER 1 (HIC1) AND GATA BINDING PROTEIN-4 (GATA-4) IN GASTRIC BIOPSY SAMPLES FROM CHILDREN AND ADULTS INFECTED OR UNINFECTED WITH THE BACTERIUM AND IN SAMPLES OBTAINED FROM GASTRIC CANCER PATIENTS. METHODS: THE METHYLATION PATTERN WAS ANALYZED WITH METHYLATION-SPECIFIC PCR. RESULTS: OUR RESULTS SHOWED THAT H. PYLORI INFECTION WAS ASSOCIATED WITH METHYLATION OF THE PROMOTER REGIONS OF THE THBS1 AND GATA-4 GENES IN PEDIATRIC AND ADULT SAMPLES (P < 0.01). HIC1 SHOWED THE LOWEST LEVEL OF METHYLATION, WHICH WAS NOT AN EARLY EVENT DURING GASTRIC CARCINOGENESIS. CONCLUSIONS: THE RESULTS FROM THIS STUDY INDICATE THAT METHYLATION OF THBS1 AND GATA-4 OCCURS IN THE EARLY STAGES OF CHRONIC GASTRITIS AND GASTRIC CANCER IN ASSOCIATION WITH H. PYLORI INFECTION; HOWEVER, IN GASTRIC CANCER SAMPLES, OTHER MECHANISMS COOPERATE WITH THE DOWN-REGULATION OF THESE GENES. METHYLATION OF HIC1 MAY NOT BE THE PRINCIPAL MECHANISM IMPLICATED IN ITS DOWN-REGULATION IN GASTRIC CANCER SAMPLES. 2013 19 5277 30 PROMOTER METHYLATION PROFILE IN PRENEOPLASTIC AND NEOPLASTIC GALLBLADDER LESIONS. GALLBLADDER CARCINOMA (GBC) IS A HIGHLY MALIGNANT NEOPLASM AND REPRESENTS THE LEADING CAUSE OF CANCER DEATH IN CHILEAN WOMEN. IN ORDER TO DETERMINE THE POTENTIAL ROLE OF PROMOTER METHYLATION IN GALLBLADDER CARCINOGENESIS, WE INVESTIGATED THE FREQUENCY OF THIS EPIGENETIC MECHANISM BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) IN 35 CHRONIC CHOLECYSTITIS (CC, SEPARATED ACCORDING TO THE PRESENCE OR ABSENCE OF METAPLASIA), 19 EARLY CANCERS (MUCOSA OR MUSCULARIS PROPIA INVASION) AND 48 ADVANCED CARCINOMAS WITH INVASION OF THE GALLBLADDER SUBSEROSA (25 CASES) AND SEROSA (23 CASES). WE EXAMINED 14 GENES AND OBSERVED AN INCREASE OF MULTIGENIC METHYLATION DURING TUMORAL PROGRESSION WHICH WAS NOT SIGNIFICANTLY ASSOCIATED WITH THE PATIENT'S AGE. FOUR GENES (DAPK1, DLC1, TIMP3, AND RARBETA2) DISPLAYED A PROGRESSIVE INCREASE IN THEIR METHYLATION STATUS FROM CC WITHOUT METAPLASIA TO ADVANCED CARCINOMA INVADING THE SEROSA LAYER (P