1 564 149 BASAL CELL CARCINOMAS OF THE SCALP AFTER RADIOTHERAPY FOR TINEA CAPITIS IN CHILDHOOD: A GENETIC AND EPIGENETIC STUDY WITH COMPARISON WITH BASAL CELL CARCINOMAS EVOLVING IN CHRONICALLY SUN-EXPOSED AREAS. BACKGROUND: BASAL CELL CARCINOMA (BCC) HAS BEEN MOSTLY ASSOCIATED WITH SUN EXPOSURE, BUT IONIZING RADIATION IS ALSO A KNOWN RISK FACTOR. IT IS NOT CLEAR IF THE PATHOGENESIS OF BCC, NAMELY AT A GENOMIC AND EPIGENETIC LEVEL, DIFFERS ACCORDING TO THE UNDERLYING TRIGGERING FACTORS. OBJECTIVE: THE PRESENT STUDY AIMS TO COMPARE GENETIC AND EPIGENETIC CHANGES IN BCCS RELATED TO IONIZING RADIATION AND CHRONIC SUN EXPOSURE. METHODS: TUMOR SAMPLES FROM BCCS OF THE SCALP IN PATIENTS SUBMITTED TO RADIOTHERAPY TO TREAT TINEA CAPITIS IN CHILDHOOD AND BCCS FROM SUN-EXPOSED AREAS WERE ANALYSED THROUGH ARRAY COMPARATIVE GENOMIC HYBRIDIZATION (ARRAY-CGH) AND METHYLATION-SPECIFIC MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION (MS-MLPA) TO DETECT COPY NUMBER ALTERATIONS AND METHYLATION STATUS OF SPECIFIC GENES. RESULTS: GENOMIC CHARACTERIZATION OF TUMOR SAMPLES REVEALED SEVERAL COPY NUMBER GAINS AND LOSSES IN ALL CHROMOSOMES, WITH THE MOST FREQUENT GAINS OBSERVED AT 2P, 6P, 12P, 14Q, 15Q, 18Q, XP AND YP, AND THE MOST FREQUENT LOSSES OBSERVED AT 3Q, 14Q, 16P, 17Q, 22Q, XP, YP AND YQ. WE DEVELOPED A STATISTICAL MODEL, ENCOMPASSING GAINS IN 3P AND 16P AND LOSSES IN 14Q AND 20P, WITH POTENTIAL TO DISCRIMINATE BCC SAMPLES WITH SPORADIC AETIOLOGY FROM BCC SAMPLES THAT EVOLVE AFTER RADIOTHERAPY IN CHILDHOOD FOR THE TREATMENT OF TINEA CAPITIS, WHICH PRESENTED STATISTICAL SIGNIFICANCE (P = 0.003). FEW METHYLATED GENES WERE DETECTED THROUGH MS-MLPA, MOST FREQUENTLY RARB AND CD44. CONCLUSIONS: OUR STUDY REPRESENTS A STEP FORWARD IN THE UNDERSTANDING OF THE GENETIC MECHANISMS UNDERLYING THE PATHOGENESIS OF BCC AND SUGGESTS POTENTIAL DIFFERENCES ACCORDING TO THE UNDERLYING RIS K FACTORS. 2021 2 4248 42 METHYLATION STATUS, MRNA AND PROTEIN EXPRESSION OF THE SMAD4 GENE IN PATIENTS WITH NON-MELANOCYTIC SKIN CANCERS. BACKGROUND: SMAD4 IS A POTENT TUMOR SUPPRESSOR. SMAD4 LOSS INCREASES GENOMIC INSTABILITY AND PLAYS A CRITICAL ROLE IN THE DNA DAMAGE RESPONSE THAT LEADS TO SKIN CANCER DEVELOPMENT. WE AIMED TO INVESTIGATE SMAD4 METHYLATION EFFECTS ON MRNA AND PROTEIN EXPRESSION OF SMAD4 IN CANCER AND HEALTHY TISSUES FROM PATIENTS WITH BASAL CELL CARCINOMA (BCC), CUTANEOUS SQUAMOUS CELL CARCINOMA (CSCC), AND BASOSQUAMOUS SKIN CANCER (BSC). METHODS AND RESULTS: THE STUDY INCLUDED 17 BCC, 24 CSCC AND NINE BSC PATIENTS. DNA AND RNA WERE ISOLATED FROM CANCEROUS AND HEALTHY TISSUES FOLLOWING PUNCH BIOPSY. METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (PCR) AND REAL-TIME QUANTITATIVE PCR METHODS WERE USED TO EXAMINE SMAD4 PROMOTER METHYLATION AND SMAD4 MRNA LEVELS, RESPECTIVELY. THE PERCENTAGE AND INTENSITY OF STAINING OF THE SMAD4 PROTEIN WERE DETERMINED BY IMMUNOHISTOCHEMISTRY. THE PERCENTAGE OF SMAD4 METHYLATION WAS INCREASED IN THE PATIENTS WITH BCC (P = 0.007), CSCC (P = 0.004), AND BSC (P = 0.018) COMPARED TO THE HEALTHY TISSUE. SMAD4 MRNA EXPRESSION WAS DECREASED IN THE PATIENTS WITH BCC (P<0.001), CSCC (P<0.001), AND BSC (P = 0.008). THE STAINING CHARACTERISTIC OF SMAD4 PROTEIN WAS NEGATIVE IN THE CANCER TISSUES OF THE PATIENTS WITH CSCC (P = 0.00). LOWER SMAD4 MRNA LEVELS WERE OBSERVED IN THE POORLY DIFFERENTIATED CSCC PATIENTS (P = 0.001). THE STAINING CHARACTERISTICS OF THE SMAD4 PROTEIN WERE RELATED TO AGE AND CHRONIC SUN EXPOSURE. CONCLUSIONS: HYPERMETHYLATION OF SMAD4 AND REDUCED SMAD4 MRNA EXPRESSION WERE FOUND TO PLAY A ROLE IN THE PATHOGENESIS OF BCC, CSCC, AND BSC. A DECREASE IN SMAD4 PROTEIN EXPRESSION LEVEL WAS OBSERVED ONLY IN CSCC PATIENTS. THIS SUGGESTS THAT EPIGENETIC ALTERATIONS TO THE SMAD4 GENE ARE ASSOCIATED WITH CSCC. TRIAL REGISTRATION: THE NAME OF THE TRIAL REGISTER: SMAD4 METHYLATION AND EXPRESSION LEVELS IN NON-MELANOCYTIC SKIN CANCERS; SMAD4 PROTEIN POSITIVITY. THE REGISTRATION NUMBER: NCT04759261 ( HTTPS://CLINICALTRIALS.GOV/CT2/RESULTS?TERM=NCT04759261 ). 2023 3 4070 22 MATERNAL DIABETES, PROGRAMMING OF BETA-CELL DISORDERS AND INTERGENERATIONAL RISK OF TYPE 2 DIABETES. A SUBSTANTIAL BODY OF EVIDENCE SUGGESTS THAT AN ABNORMAL INTRA-UTERINE MILIEU ELICITED BY MATERNAL METABOLIC DISTURBANCES AS DIVERSE AS MALNUTRITION, PLACENTAL INSUFFICIENCY, DIABETES AND OBESITY MAY BE ABLE TO PROGRAMME SUSCEPTIBILITY OF THE FOETUS TO LATER DEVELOP CHRONIC DEGENERATIVE DISEASES SUCH AS OBESITY, HYPERTENSION, CARDIOVASCULAR DISEASES AND TYPE 2 DIABETES (T2D). AS INSULIN-PRODUCING CELLS HAVE BEEN PLACED CENTRE STAGE IN THE DEVELOPMENT OF T2D, THIS REVIEW EXAMINES DEVELOPMENTAL PROGRAMMING OF THE BETA-CELL MASS (BCM) IN VARIOUS RODENT MODELS OF MATERNAL PROTEIN RESTRICTION, CALORIE RESTRICTION, OVERNUTRITION AND DIABETES. THE MAIN MESSAGE IS THAT WHATEVER THE INITIAL MATERNAL INSULT (F0 GENERATION) AND WHETHER ALONE OR IN COMBINATION, IT GIVES RISE TO THE SAME PROGRAMMED BCM OUTCOME IN THE DAUGHTER GENERATION (F1). THE ALTERED BCM PHENOTYPE IN F1 FEMALES PROHIBITS NORMAL BCM ADAPTATION DURING PREGNANCY AND, THUS, DIABETES (GESTATIONAL DIABETES) ENSUES. THIS GESTATIONAL DIABETES IS THEN PASSED FROM ONE GENERATION (F1) TO THE NEXT (F2, F3 AND SO ON). THIS REVIEW HIGHLIGHTS A NUMBER OF STUDIES THAT HAVE IDENTIFIED EPIGENETIC MECHANISMS THAT MAY CONTRIBUTE TO ALTERED BCM DEVELOPMENT AND BETA-CELL FAILURE, AS OBSERVED IN DIABETES. IN ADDITION TO THEIR ROLE IN INSTILLING THE PROGRAMMED DEFECT, THESE NON-GENOMIC MECHANISMS MAY ALSO BE INVOLVED IN ITS INTERGENERATIONAL TRANSMISSION. 2014 4 2261 34 EPIGENETIC PROFILE IN CHRONIC LYMPHOCYTIC LEUKEMIA USING METHYLATION-SPECIFIC MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION. AIM: TO ANALYZE THE METHYLATION STATUS OF 35 TUMOR SUPPRESSOR GENES USING METHYLATION-SPECIFIC MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION (MS-MLPA) IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). MATERIALS & METHODS: THE DNA OF 37 SAMPLES FROM PATIENTS WITH CLL, SIX HEALTHY DONORS, AND JURKAT AND RAMOS CELL LINES WAS ANALYZED BY MS-MLPA. RESULTS: OUR RESULTS CONFIRM THAT HYPERMETHYLATION IS A COMMON AND NOT RANDOMLY DISTRIBUTED EVENT IN CLL, AND SOME GENES, SUCH AS WT1, CDH13, IGSF4/TSLC1, GATA5, DAPK1 AND RARB, ARE HYPERMETHYLATED IN MORE THAN 25% OF THE ANALYZED SAMPLES. IMPORTANTLY, MS-MLPA ALSO DETECTED HYPERMETHYLATION OF SOME GENES NOT REPORTED PREVIOUSLY IN CLL, AND THEIR METHYLATION STATUS WAS CONFIRMED BY BISULFITE SEQUENCING. CONCLUSION: THESE RESULTS INDICATE THAT MS-MLPA IS A USEFUL TECHNIQUE FOR THE DETECTION OF METHYLATION IN CLL SAMPLES. SELECTING CLL-SPECIFIC METHYLATION TARGETS IN ORDER TO GENERATE A CLL-SPECIFIC MS-MLPA PROBE SET COULD ENHANCE ITS USEFULNESS AS A TOOL IN STUDIES OF RISK STRATIFICATION AND GUIDING THE BEST THERAPEUTIC DECISION. 2012 5 2830 37 FOCAL 9P INSTABILITY IN HEMATOLOGIC NEOPLASIAS REVEALED BY COMPARATIVE GENOMIC HYBRIDIZATION AND SINGLE-NUCLEOTIDE POLYMORPHISM MICROARRAY ANALYSES. COPY NUMBER LOSSES IN CHROMOSOME ARM 9P ARE WELL-KNOWN ABERRATIONS IN MALIGNANCIES, INCLUDING LEUKEMIAS. THE CDKN2A GENE IS SUGGESTED TO PLAY A KEY ROLE IN THESE ABERRATIONS. IN THIS STUDY OVERVIEWING 9P LOSSES IN HEMATOLOGIC NEOPLASIAS, WE INTRODUCE THE TERM FOCAL 9P INSTABILITY TO INDICATE MULTIPLE AREAS OF COPY NUMBER LOSS OR HOMOZYGOUS LOSS WITHIN A LARGER HETEROZYGOUS ONE IN 9P. WE HAVE USED MICROARRAY COMPARATIVE GENOMIC HYBRIDIZATION TO STUDY PATIENTS WITH ACUTE LYMPHOBLASTIC LEUKEMIA (ALL, N = 140), ACUTE MYELOID LEUKEMIA (N = 50), CHRONIC LYMPHOCYTIC LEUKEMIA (N = 20), AND MYELODYSPLASTIC SYNDROMES (N = 37). OUR RESULTS SHOW THAT 9P INSTABILITY IS RESTRICTED TO ALL. IN TOTAL, 58/140 (41%) PATIENTS WITH ALL HAD A LOSS IN 9P. THE 9P INSTABILITY WAS DETECTED IN 19% OF THE PATIENTS WITH ALL AND ALWAYS INCLUDED HOMOZYGOUS LOSS OF CDKN2A ALONG WITH LOSS OF CDKN2B. OTHER POSSIBLY IMPORTANT GENES INCLUDED MTAP, IFN, MLLT3, JAK2, PTPLAD2, AND PAX5. 13/27 (48%) PATIENTS WITH THE INSTABILITY HAD THE BCR/ABL1 FUSION GENE OR OTHER ONCOGENE-ACTIVATING TRANSLOCATION OR STRUCTURAL ABERRATIONS. TWO PATIENTS HAD HOMOZYGOUS LOSS OF HSA-MIR -31, A MICRORNA KNOWN TO REGULATE IKZF1. IKZF1 DELETION AT 7P12.1 WAS SEEN IN 10 (37%) PATIENTS WITH THE 9P INSTABILITY. THESE FINDINGS SUGGEST THAT, IN ALL LEUKEMOGENESIS, LOSS OF CDKN2A AND OTHER TARGET GENES IN THE INSTABILITY REGION IS FREQUENTLY ASSOCIATED WITH BCR/ABL1 AND IKZF1 DYSFUNCTION. THE MULTIPLE MECHANISMS LEADING TO 9P INSTABILITY INCLUDING PHYSICAL OR EPIGENETIC LOSS OF THE TARGET GENES, LOSS OF THE MICRORNA CLUSTER, AND THE ROLE OF FRA9G FRAGILE SITE ARE DISCUSSED. 2010 6 417 31 ANATOMIC SITE-SPECIFIC PATTERNS OF GENE COPY NUMBER GAINS IN SKIN, MUCOSAL, AND UVEAL MELANOMAS DETECTED BY FLUORESCENCE IN SITU HYBRIDIZATION. TO ASSESS THE DIFFERENCES BETWEEN MELANOMAS OF DIFFERENT LOCATION AND DIFFERENT ETIOLOGY, 372 MALIGNANT MELANOMAS WERE BROUGHT IN A TISSUE MICROARRAY FORMAT. THE COLLECTION INCLUDED 23 ACRAL AND 118 NON-ACRAL SKIN MELANOMAS, 9 MUCOSAL MELANOMAS, 100 UVEAL MELANOMAS, AND 122 MELANOMA METASTASES. FLUORESCENCE IN SITU HYBRIDIZATION (FISH) WAS USED TO ASSESS COPY NUMBER CHANGES OF THE CYCLIN D1 (CCND1), MDM2, C-MYC (MYC), AND HER2 GENES. FISH ANALYSIS REVEALED DISTINCT DIFFERENCES BETWEEN MELANOMAS FROM DIFFERENT LOCATIONS. CCND1 AMPLIFICATIONS WERE DETECTED IN SKIN MELANOMAS FROM SITES WITH CHRONIC SUN EXPOSURE (6 OF 32 CASES), ACRAL MELANOMAS (4 OF 17 CASES), AND MUCOSAL MELANOMAS (ONE OF TEN CASES) BUT NOT IN UVEAL MELANOMAS. HIGH-LEVEL MDM2 AMPLIFICATIONS WERE EXCLUSIVELY PRESENT IN ACRAL MELANOMAS (2 OF 19 CASES). MYC COPY NUMBER GAINS WERE DETECTED IN 32 OF 71 UVEAL MELANOMAS, FIVE OF EIGHT MUCOSAL MELANOMAS, AND 6 OF 67 MELANOMAS FROM SITES WITH INTERMITTENT SUN EXPOSURE BUT NOT IN ACRAL MELANOMAS NOR MELANOMAS FROM SITES WITH CHRONIC SUN EXPOSURE. ALTERATIONS OF THE MYC GENE WERE ASSOCIATED WITH ADVANCED TUMOR STAGE. THERE WERE NO HIGH-LEVEL HER2 AMPLIFICATIONS. SITE-SPECIFIC GENETIC AND EPIGENETIC FEATURES MAY IMPACT THE RESPONSE OF MELANOMAS TO VARIOUS ANTI-CANCER DRUGS AND SHOULD BE CONSIDERED IN FUTURE STUDIES ON THE MOLECULAR PATHOGENESIS OF MALIGNANT MELANOMAS. 2006 7 159 42 ABERRANT PROMOTER HYPERMETHYLATION OF MULTIPLE GENES IN GALLBLADDER CARCINOMA AND CHRONIC CHOLECYSTITIS. PURPOSE: ABERRANT METHYLATION OF 5' GENE PROMOTER REGIONS IS AN EPIGENETIC PHENOMENON THAT IS A MAJOR MECHANISM FOR SILENCING OF TUMOR SUPPRESSOR GENES IN MANY CANCER TYPES. THERE IS LIMITED INFORMATION ABOUT THE MOLECULAR CHANGES INVOLVED IN THE PATHOGENESIS OF GALLBLADDER CARCINOMA (GBC), INCLUDING METHYLATION STATUS. EXPERIMENTAL DESIGN: WE INVESTIGATED THE ABERRANT PROMOTER METHYLATION PROFILE OF 24 KNOWN OR SUSPECTED TUMOR SUPPRESSOR GENES IN 50 GBCS AND COMPARED THOSE RESULTS WITH THE FINDINGS IN 25 CHRONIC CHOLECYSTITIS (CC) SPECIMENS WITHOUT CANCER. THE METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION AND COMBINED RESTRICTION ANALYSIS METHODS WERE USED TO DETECT METHYLATION, AND THE RESULTS WERE CONFIRMED BY SEQUENCING OF CLONED POLYMERASE CHAIN REACTION PRODUCTS. RESULTS: IN GBC, GENE METHYLATION FREQUENCIES VARIED FROM 0% TO 80%. TEN GENES DEMONSTRATED RELATIVELY HIGH FREQUENCIES OF ABERRANT METHYLATION: SHP1 (80%), 3-OST-2 (72%), CDH13 (44%), P15INK4B (44%), CDH1 (38%), RUNX3 (32%), APC (30%), RIZ1 (26%), P16INK4A (24%), AND HPP1 (20%). EIGHT GENES (P73, RARBETA2, SOCS-1, DAPK, DCR2, DCR1, HIN1, AND CHFR) SHOWED LOW FREQUENCIES (2-14%) OF METHYLATION, AND NO METHYLATION OF THE REMAINING SIX GENES (TIMP-3, P57, RASSF1A, CRBP1, SYK, AND NORE1) WAS DETECTED. IN CC, METHYLATION WAS DETECTED FOR SEVEN GENES: SHP1 (88%), P15INK4B (28%), 3-OST-2 (12%), CDH1 (12%), CDH13 (8%), DCR2 (4%), AND P16INK4A (4%). SIGNIFICANTLY HIGHER FREQUENCIES OF METHYLATION IN GBC COMPARED WITH CC WERE DETECTED FOR EIGHT GENES (3-OST-2, CDH13, CDH1, RUNX3, APC, RIZ1, P16INK4A, AND HPP1). OF THOSE, FOUR GENES SHOWED FREQUENT METHYLATION (>30%) IN GBCS. THE MEAN METHYLATION INDEX, AN EXPRESSION OF THE AMOUNT OF METHYLATED GENES BY CASE, WAS SIGNIFICANTLY HIGHER IN GBC (0.196 +/- 0.013) COMPARED WITH CC (0.065 +/- 0.008; P < 0.001). CONCLUSIONS: OUR STUDY CONSTITUTES THE MOST COMPREHENSIVE METHYLATION PROFILE REPORT AVAILABLE IN GBC AND DEMONSTRATES THAT THIS NEOPLASM HAS A DISTINCT PATTERN OF ABNORMAL GENE METHYLATION. WHEREAS GALLBLADDERS FROM HEALTHY INDIVIDUAL WERE NOT AVAILABLE, OUR FINDING OF METHYLATION IN CC CASES WITHOUT CANCER SUGGESTS THAT THIS PHENOMENON REPRESENTS AN EARLY EVENT IN THE PATHOGENESIS OF GBC. 2004 8 999 35 CHRONIC SUN EXPOSURE IS ASSOCIATED WITH DISTINCT HISTONE ACETYLATION CHANGES IN HUMAN SKIN. BACKGROUND: PHOTOAGEING IS ATTRIBUTED TO CONTINUOUS SUNLIGHT OR ARTIFICIAL ULTRAVIOLET EXPOSURE AND MANIFESTS AS CLINICAL AND HISTOLOGICAL CHANGES IN SKIN. EPIGENETIC CHANGES HAVE BEEN FOUND TO BE INVOLVED IN THE PATHOGENESIS OF PHOTOAGEING. HOWEVER, THE UNDERLYING MECHANISMS ARE UNCLEAR. OBJECTIVES: TO ANALYSE HISTONE MODIFICATION PATTERNS IN SUN-EXPOSED AND NONEXPOSED SKIN, AND TO IDENTIFY THE ABNORMALLY HISTONE-MODIFIED GENES RELATED TO PHOTOAGEING. METHODS: SKIN BIOPSIES WERE COLLECTED FROM BOTH THE OUTER FOREARM (SUN-EXPOSED AREA) AND THE BUTTOCK (SUN-PROTECTED AREA) IN 20 HEALTHY MIDDLE-AGED FEMALE VOLUNTEERS. GLOBAL HISTONE H3/H4 ACETYLATION AND H3K4/H3K9 METHYLATION STATUSES WERE ASSESSED BY ENZYME-LINKED IMMUNOSORBENT ASSAY. EXPRESSION LEVELS OF HISTONE ACETYLTRANSFERASES AND HISTONE DEACETYLASES WERE MEASURED BY REVERSE-TRANSCRIPTASE QUANTITATIVE POLYMERASE CHAIN REACTION (QPCR) AND WESTERN BLOT. CHROMATIN IMMUNOPRECIPITATION COMBINED WITH DNA MICROARRAY (CHIP-CHIP) ASSAY WITH ANTI-ACETYL-HISTONE H3 ANTIBODY IN A SUN-EXPOSED POOL (COMBINING SIX SUN-EXPOSED SKIN SAMPLES) AND A NONEXPOSED POOL (COMBINING SIX NONEXPOSED SKIN SAMPLES) WAS CONDUCTED TO EXPLORE THE ABNORMALLY ACETYLATED HISTONE H3 GENES RELATED TO PHOTOAGEING; CHIP-QPCR WAS THEN USED TO VERIFY THE RESULTS OF CHIP-CHIP. RESULTS: WE OBSERVED HIGHER GLOBAL HISTONE H3 ACETYLATION LEVELS INCREASED EP300 AND DECREASED HDAC1 AND SIRT1 EXPRESSION IN SUN-EXPOSED SKIN COMPARED WITH MATCHED NONEXPOSED SKIN. FURTHERMORE, THE CHIP-CHIP ASSAY SHOWED THAT 227 GENES DISPLAYED SIGNIFICANT HYPERACETYLATION OF HISTONE H3, AND 81 GENES DISPLAYED SIGNIFICANT HYPOACETYLATION OF HISTONE H3 BETWEEN THE TWO GROUPS. HISTONE H3 ACETYLATION LEVELS ON THE PROMOTERS OF PDCD5, ITIH5, MMP1 AND AHR WERE POSITIVELY CORRELATED WITH THE MRNA EXPRESSION OF THE CORRESPONDING GENE. CONCLUSIONS: CHRONIC SUN EXPOSURE-INDUCED HISTONE H3 HYPERACETYLATION MAY PLAY A CRITICAL ROLE IN THE PATHOGENESIS OF SKIN PHOTOAGEING. 2018 9 4245 36 METHYLATION STATUS OF DDIT3 GENE IN CHRONIC MYELOID LEUKEMIA. BACKGROUND: DNA-DAMAGE-INDUCIBLE TRANSCRIPT 3 (DDIT3), A CANDIDATE TUMOR SUPPRESSOR GENE (TSG), HAS BEEN FOUND INVOLVED IN THE REGULATION OF CELLULAR GROWTH AND DIFFERENTIATION. THE EPIGENETIC CHANGES OF TSGS ARE RECENTLY RECOGNIZED AS AN ABNORMAL MECHANISM CONTRIBUTING TO THE DEVELOPMENT OF CHRONIC MYELOID LEUKEMIA (CML). THE AIM OF THIS STUDY WAS TO INVESTIGATE THE METHYLATION STATUS OF DDIT3 GENE IN CML PATIENTS. METHODS: THE METHYLATION STATUS OF DDIT3 PROMOTER WAS DETECTED IN THE BONE MARROW MONONUCLEAR CELLS FROM 53 PATIENTS WITH CML USING METHYLATION-SPECIFIC PCR (MSP). THE EXPRESSION LEVELS OF DDIT3 AND BCR/ABL TRANSCRIPT WERE DETERMINED BY REAL-TIME QUANTITATIVE PCR (RQ-PCR). CLINICAL DATA OF THESE PATIENTS WERE COLLECTED AND ANALYZED. RESULTS: THE ABERRANT METHYLATION OF DDIT3 GENE PROMOTER WAS FOUND IN 35 OF 53 (66%) CML CASES. CORRELATION WAS NOT FOUND BETWEEN DDIT3 PROMOTER HYPERMETHYLATION AND THE AGE, SEX, HEMOGLOBIN CONCENTRATION, PLATELET COUNTS, CHROMOSOMAL ABNORMALITIES, BCR/ABL TRANSCRIPT, AND STAGING OF CML PATIENTS (P > 0.05), BUT FOUND BETWEEN DDIT3 PROMOTER HYPERMETHYLATION AND WBC COUNTS OF CML CASES (R = 0.781, P < 0.001). THE LEVEL OF DDIT3 TRANSCRIPT IN CML PATIENTS WAS SIGNIFICANTLY LOWER THAN THAT IN CONTROLS (MEDIAN 3.28 VS 19.69, P < 0.001), HOWEVER, THERE WAS NO DIFFERENCE IN THE LEVEL OF DDIT3 TRANSCRIPT BETWEEN METHYLATION-POSITIVE CML CASES (0.05-65.32, MEDIAN 2.13) AND METHYLATION- NEGATIVE CML CASES (0.12-126.04, MEDIAN 3.92) (P > 0.05). CONCLUSION: OUR RESULTS DEMONSTRATE THAT ABERRANT METHYLATION OF DDIT3 OCCURS IN CML FREQUENTLY. 2010 10 270 34 AGE AND SUN EXPOSURE-RELATED WIDESPREAD GENOMIC BLOCKS OF HYPOMETHYLATION IN NONMALIGNANT SKIN. BACKGROUND: AGING AND SUN EXPOSURE ARE THE LEADING CAUSES OF SKIN CANCER. IT HAS BEEN SHOWN THAT EPIGENETIC CHANGES, SUCH AS DNA METHYLATION, ARE WELL ESTABLISHED MECHANISMS FOR CANCER, AND ALSO HAVE EMERGING ROLES IN AGING AND COMMON DISEASE. HERE, WE DIRECTLY ASK WHETHER DNA METHYLATION IS ALTERED FOLLOWING SKIN AGING AND/OR CHRONIC SUN EXPOSURE IN HUMANS. RESULTS: WE COMPARE EPIDERMIS AND DERMIS OF BOTH SUN-PROTECTED AND SUN-EXPOSED SKIN DERIVED FROM YOUNGER SUBJECTS (UNDER 35 YEARS OLD) AND OLDER SUBJECTS (OVER 60 YEARS OLD), USING THE INFINIUM HUMANMETHYLATION450 ARRAY AND WHOLE GENOME BISULFITE SEQUENCING. WE OBSERVE LARGE BLOCKS OF THE GENOME THAT ARE HYPOMETHYLATED IN OLDER, SUN-EXPOSED EPIDERMAL SAMPLES, WITH THE DEGREE OF HYPOMETHYLATION ASSOCIATED WITH CLINICAL MEASURES OF PHOTO-AGING. WE REPLICATE THESE FINDINGS USING WHOLE GENOME BISULFITE SEQUENCING, COMPARING EPIDERMIS FROM AN ADDITIONAL SET OF YOUNGER AND OLDER SUBJECTS. THESE BLOCKS LARGELY OVERLAP KNOWN HYPOMETHYLATED BLOCKS IN COLON CANCER AND WE OBSERVE THAT THESE SAME REGIONS ARE SIMILARLY HYPOMETHYLATED IN SQUAMOUS CELL CARCINOMA SAMPLES. CONCLUSIONS: THESE DATA IMPLICATE LARGE SCALE EPIGENOMIC CHANGE IN MEDIATING THE EFFECTS OF ENVIRONMENTAL DAMAGE WITH PHOTO-AGING. 2015 11 6415 30 THE STUDY OF P16 AND P15 GENE METHYLATION IN HEAD AND NECK SQUAMOUS CELL CARCINOMA AND THEIR QUANTITATIVE EVALUATION IN PLASMA BY REAL-TIME PCR. EPIGENETIC SILENCING OF THE P16 AND P15 GENES BY PROMOTER METHYLATION ARE COMMONLY OBSERVED IN HUMAN EPITHELIAL MALIGNANCIES, INCLUDING HEAD AND NECK SQUAMOUS CELL CARCINOMAS (HNSCC). IN THIS STUDY, A METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) WAS USED TO EVALUATE THE METHYLATION STATUS OF THE P16 AND P15 GENES IN 73 HNSCC SURGICAL SPECIMENS. P16 AND P15 GENE METHYLATION WAS ALSO EXAMINED IN 29 PAIRED METASTATIC LYMPH NODES AND 29 PAIRED HISTOLOGICALLY, NORMAL RESECTION MARGIN MUCOSAE. THE QUANTITY OF CELL-FREE METHYLATED P16 AND P15 DNA IN THE PLASMA SAMPLES OF 20 HNSCC PATIENTS AND 24 HEALTHY CONTROLS WAS ALSO EXAMINED USING A FLUORESCENCE-BASED REAL-TIME PCR ASSAY. THE FREQUENCIES OF P16 AND P15 METHYLATION IN THE PRIMARY TUMOUR WERE 49% AND 60%, RESPECTIVELY. CONCORDANT METHYLATION OF P16 AND P15 IN TUMOUR SAMPLES AND METASTATIC LYMPH NODES WAS FOUND IN 59 AND 38% OF CASES, RESPECTIVELY. A SIGNIFICANTLY HIGHER PREVALENCE OF P15 METHYLATION WAS FOUND IN HISTOLOGICALLY-NORMAL SURGICAL MARGIN EPITHELIA OF HNSCC PATIENTS WITH CHRONIC SMOKING AND DRINKING HABITS COMPARED WITH NON-SMOKERS AND NON-DRINKERS. IN ADDITION, METHYLATED P16 AND P15 DNA LEVELS WERE SIGNIFICANTLY HIGHER IN THE PLASMA OF HNSCC PATIENTS (MEAN 56 COPIES/ML PLASMA AND 65 COPIES/ML PLASMA, RESPECTIVELY) COMPARED WITH NORMAL CONTROLS (MEAN 6 COPIES/ML PLASMA AND 16 COPIES/ML PLASMA, RESPECTIVELY). IN CONCLUSION, PROMOTER METHYLATION OF THE P16 AND P15 GENES IS INVOLVED IN THE PATHOGENESIS OF HNSCC AND MAY BE RELATED TO CHRONIC SMOKING AND DRINKING. THE DIFFERENTIAL LEVELS OF METHYLATED P16 AND P15 DNA IN PLASMA MIGHT BE POTENTIAL USEFUL MARKERS IN SCREENING HIGH-RISK POPULATIONS FOR EARLY HNSCC AND MONITORING THEIR TREATMENT RESPONSE. 2003 12 1107 33 COMBINING CYTOGENETIC AND EPIGENETIC APPROACHES IN CHRONIC LYMPHOCYTIC LEUKEMIA IMPROVES PROGNOSIS PREDICTION FOR PATIENTS WITH ISOLATED 13Q DELETION. BACKGROUND: BOTH DEFECTIVE DNA METHYLATION AND ACTIVE DNA DEMETHYLATION PROCESSES ARE EMERGING AS IMPORTANT RISK FACTORS IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). HOWEVER, ASSOCIATIONS BETWEEN 5-CYTOSINE EPIGENETIC MARKERS AND THE MOST FREQUENT CHROMOSOMAL ABNORMALITIES DETECTED IN CLL REMAIN TO BE ESTABLISHED. METHODS: CLL PATIENTS WERE RETROSPECTIVELY CLASSIFIED INTO A CYTOGENETIC LOW-RISK GROUP (ISOLATED 13Q DELETION), AN INTERMEDIATE-RISK GROUP (NORMAL KARYOTYPE OR TRISOMY 12), AND A HIGH-RISK GROUP (11Q DELETION, 17P DELETION, OR COMPLEX KARYOTYPE [>/= 3 BREAKPOINTS]). THE TWO 5-CYTOSINE DERIVATIVES, 5-METHYLCYTOSINE (5-MCYT) AND 5-HYDROXYMETHYLCYTOSINE (5-HMCYT), WERE TESTED BY ELISA (N = 60), WHILE REAL-TIME QUANTITATIVE PCR WAS USED FOR DETERMINING TRANSCRIPTIONAL EXPRESSION LEVELS OF DNMT AND TET (N = 24). RESULTS: BY USING GLOBAL DNA METHYLATION/DEMETHYLATION LEVELS, IN THE LOW-RISK DISEASE GROUP, TWO SUBGROUPS WITH SIGNIFICANTLY DIFFERENT CLINICAL OUTCOMES HAVE BEEN IDENTIFIED (MEDIAN TREATMENT-FREE SURVIVAL [TFS] 45 VERSUS > 120 MONTHS FOR 5-MCYT, P = 0.0008, AND 63 VERSUS > 120 MONTHS FOR 5-HMCYT, P = 0.04). A DEFECTIVE 5-MCYT STATUS WAS FURTHER ASSOCIATED WITH A HIGHER PERCENTAGE OF 13Q DELETED NUCLEI (> 80%), THUS SUGGESTING AN ACQUIRED PROCESS. WHEN CONSIDERING THE CYTOGENETIC INTERMEDIATE/HIGH-RISK DISEASE GROUPS, AN ASSOCIATION OF 5-MCYT STATUS WITH LYMPHOCYTOSIS (P = 0.0008) AND THE LYMPHOCYTE DOUBLING TIME (P = 0.04) BUT NOT WITH TFS WAS OBSERVED, AS WELL AS A REDUCTION OF DNMT3A, TET1, AND TET2 TRANSCRIPTS. CONCLUSIONS: COMBINING CYTOGENETIC STUDIES WITH 5-MCYT ASSESSMENT ADDS ACCURACY TO CLL PATIENTS' PROGNOSES AND PARTICULARLY FOR THOSE WITH 13Q DELETION AS A SOLE CYTOGENETIC ABNORMALITY. 2017 13 143 31 ABERRANT DNA METHYLATION OF TWO TUMOR SUPPRESSOR GENES, P14(ARF) AND P15(INK4B), AFTER CHRONIC OCCUPATIONAL EXPOSURE TO LOW LEVEL OF BENZENE. BACKGROUND: EXPOSURE TO BENZENE WOULD BE ASSOCIATED WITH MANY DISEASES INCLUDING LEUKEMIA. EPIGENETIC ALTERATIONS SEEM TO BE AMONG THE MAIN MECHANISMS INVOLVED. OBJECTIVE: TO DETERMINE IF CHRONIC OCCUPATIONAL EXPOSURE TO LOW LEVEL OF BENZENE WOULD BE ASSOCIATED WITH DNA METHYLATION. METHODS: GLOBAL DNA METHYLATION AND PROMOTER-SPECIFIC METHYLATION OF THE TWO TUMOR SUPPRESSOR GENES, P14(ARF) AND P15(INK4B), WERE ASSESSED EMPLOYING METHYLATION-SPECIFIC PCR USING THE DNA EXTRACTED FROM 40 PETROCHEMICAL WORKERS EXPOSED TO AMBIENT BENZENE LEVELS OF <1 PPM, AND 31 OFFICE WORKERS NOT EXPOSED TO BENZENE OR ITS DERIVATIVES. RESULTS: WHILE AN INCREASE IN GLOBAL DNA METHYLATION OF 5% IN P14(ARF) (P=0.501) AND 28% IN P15(INK4B) (P=0.02) GENES WAS OBSERVED IN THE EXPOSED GROUP, NO HYPERMETHYLATION IN EITHER OF THE STUDIED GENES WAS OBSERVED IN THE UNEXPOSED GROUP. NO SIGNIFICANT ASSOCIATION WAS FOUND BETWEEN THE FREQUENCY OF ABERRANT METHYLATION AND EITHER OF AGE, WORK EXPERIENCE, AND SMOKING HABIT IN THE EXPOSED GROUP. CONCLUSION: CHRONIC OCCUPATIONAL EXPOSURE TO LOWER THAN THE PERMISSIBLE EXPOSURE LIMIT OF BENZENE MAY STILL RESULT IN DNA METHYLATION OF TUMOR SUPPRESSOR GENES THAT MAY ULTIMATELY LEAD TO DEVELOPMENT OF CANCER. 2018 14 5683 32 SHORTER TELOMERE LENGTH IN PERIPHERAL BLOOD LYMPHOCYTES OF WORKERS EXPOSED TO POLYCYCLIC AROMATIC HYDROCARBONS. SHORTER TELOMERE LENGTH (TL) IN PERIPHERAL BLOOD LYMPHOCYTES (PBLS) IS PREDICTIVE OF LUNG CANCER RISK. POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) ARE ESTABLISHED LUNG CARCINOGENS THAT CAUSE CHROMOSOME INSTABILITY. WHETHER PAH EXPOSURE AND ITS MOLECULAR EFFECTS ARE LINKED WITH SHORTER TL HAS NEVER BEEN EVALUATED. IN THE PRESENT STUDY, WE INVESTIGATED THE EFFECT OF CHRONIC EXPOSURE TO PAHS ON TL MEASURED IN PBLS OF POLISH MALE NON-CURRENT SMOKING COKEOVEN WORKERS AND MATCHED CONTROLS. PAH EXPOSURE AND MOLECULAR EFFECTS WERE CHARACTERIZED USING MEASURES OF INTERNAL DOSE (URINARY 1-PYRENOL), EFFECTIVE DOSE [ANTI-BENZO[A]PYRENE DIOLEPOXIDE (ANTI-BPDE)-DNA ADDUCT], GENETIC INSTABILITY (MICRONUCLEI, MN) AND DNA METHYLATION [P53 PROMOTER AND ALU AND LONG INTERSPERSED NUCLEAR ELEMENT-1 (LINE-1) REPETITIVE ELEMENTS, AS SURROGATE MEASURES OF GLOBAL METHYLATION] IN PBLS. TL WAS MEASURED BY REAL-TIME POLYMERASE CHAIN REACTION. COKEOVEN WORKERS WERE HEAVILY EXPOSED TO PAHS (79% EXCEEDED THE URINARY 1-PYRENOL BIOLOGICAL EXPOSURE INDEX) AND EXHIBITED LOWER TL (P = 0.038) THAN CONTROLS, AS WELL AS HIGHER LEVELS OF GENETIC AND CHROMOSOMAL ALTERATIONS [I.E. ANTI-BPDE-DNA ADDUCT AND MN (P < 0.0001)] AND EPIGENETIC CHANGES [I.E. P53 GENE-SPECIFIC PROMOTER AND GLOBAL METHYLATION (P 65 YEARS, BMP3, RASSF1A, BNC1, MESTV2, TFPI2, APC, SFRP1 AND SFRP2) WAS VALIDATED ALONE AND IN COMBINATION WITH SERUM CA 19-9 IN THIS EXTERNAL PATIENT COHORT. RESULTS: PATIENTS WITH PDAC HAD A HIGHER NUMBER OF HYPERMETHYLATED GENES (MEAN 8.11, 95% CI 7.70-8.52) THAN PATIENTS WITH CHRONIC PANCREATITIS (MEAN 5.60, 95% CI 4.42-6.78, P = 0.011). VALIDATION OF THE DIAGNOSTIC PREDICTION MODEL YIELDED AN AUC OF 0.77 (95% CI 0.69-0.84). THE COMBINATION OF SERUM CA 19-9 AND OUR TEST HAD AN AUC OF 0.93 (95% CI 0.89-0.96) IN THE PRIMARY STUDY AND 0.85 (95% CI 0.79-0.91) IN THE VALIDATION STUDY. CONCLUSION: IN THIS VALIDATION STUDY, PDAC WAS ASSOCIATED WITH A HIGHER NUMBER OF HYPERMETHYLATED GENES IN SERUM CFDNA THAN CHRONIC PANCREATITIS. OUR DIAGNOSTIC TEST WAS SUPERIOR TO THE PREDICTIVE VALUE OF SERUM CA 19-9 ALONE IN BOTH THE PRIMARY AND THE VALIDATION STUDY. THE COMBINATION OF OUR TEST WITH CA 19-9 MAY SERVE AS A CLINICALLY USEFUL DIAGNOSTIC BIOMARKER FOR PDAC. 2021 17 156 32 ABERRANT METHYLATION OF THE DEATH-ASSOCIATED PROTEIN KINASE 1 (DAPK1) CPG ISLAND IN CHRONIC MYELOID LEUKEMIA. THE DEATH-ASSOCIATED PROTEIN KINASE 1 (DAPK1) GENE IS A CANDIDATE TUMOR SUPPRESSOR (TSG) AND THE ABNORMAL METHYLATION OF DAPK1 GENE HAS BEEN FOUND IN MANY CARCINOMAS. THE EPIGENETIC CHANGES OF TSGS ARE NOW RECOGNIZED AS A MECHANISM CONTRIBUTING TO THE DEVELOPMENT OF CHRONIC MYELOID LEUKEMIA (CML). TO CLARIFY THE ROLE OF DAPK1 IN CML, WE EXAMINED THE METHYLATION STATUS OF DAPK1 IN 49 PATIENTS WITH CML USING METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION. THE ABERRANT METHYLATION OF THE DAPK1 GENE WAS FOUND IN 25 OF 49 (51.0%) CML CASES, NOT IN ALL CONTROLS. NO CORRELATION WAS FOUND BETWEEN DAPK1 GENE METHYLATION AND THE AGE, HEMATOLOGIC PARAMETERS, CHROMOSOMAL ABNORMALITIES, THE TYPES AND LEVELS OF BCR/ABL TRANSCRIPTS OF CML PATIENTS. HOWEVER, CORRELATION COULD BE OBSERVED BETWEEN THE SEX AND THE STATUS OF DAPK1 METHYLATION IN CML PATIENTS (R = 0.374, P = 0.008). FURTHERMORE, THERE WAS A SIGNIFICANT CORRELATION BETWEEN DAPK1 METHYLATION AND THE STAGES OF CML (R = 0.354, P = 0.013). THE CML PATIENTS IN ACCELERATED PHASE (AP) AND BLAST CRISIS (BC) HAD HIGHER FREQUENCY OF DAPK1 METHYLATION THAN THOSE IN CHRONIC PHASE (CP) (75.0% VS. 34.5%) (CHI(2) = 7.776, P = 0.005). IN ONE PATIENT, THE STATUS OF DAPK1 METHYLATION BECAME POSITIVE ON THE TRANSITION FROM CP TO AP AND BC. THESE RESULTS SUGGESTED THAT DAPK1 PROMOTER METHYLATION MIGHT PLAY A SIGNIFICANT ROLE IN THE PROGRESSION OF CML. 2009 18 672 25 BRAF, KRAS AND HELICOBACTER PYLORI EPIGENETIC CHANGES-ASSOCIATED CHRONIC GASTRITIS IN EGYPTIAN PATIENTS WITH AND WITHOUT GASTRIC CANCER. WE AIMED TO STUDY MLH1 AND MGMT METHYLATION STATUS IN HELICOBACTER PYLORI-ASSOCIATED CHRONIC GASTRITIS IN EGYPTIAN PATIENTS WITH AND WITHOUT GASTRIC CANCER. 39 PATIENTS WERE INCLUDED IN OUR STUDY. THEY WERE DIVIDED INTO 2 GROUPS; PATIENTS WITHOUT (GROUP I) AND WITH GASTRIC ADENOCARCINOMA (GROUP II). PATIENTS WERE SUBJECTED TO CLINICAL EXAMINATION, ABDOMINAL ULTRASOUND AND UPPER ENDOSCOPY FOR GASTRIC BIOPSY. BIOPSIES WERE SUBJECTED TO UREASE TEST, HISTOLOGICAL EXAMINATION, AND DNA PURIFICATION. H. PYLORI, BRAF, KRAS, MLH1 AND MGMT METHYLATION WERE ASSESSED BY QUANTITATIVE PCR. DNA SEQUENCING WAS PERFORMED TO ASSESS BRAF AND KRAS GENES MUTATION. QPCR OF H. PYLORI WAS SIGNIFICANTLY HIGHER IN PATIENTS WITH ADENOCARCINOMA (GROUP II) THAN THOSE WITHOUT ADENOCARCINOMA (GROUP I); WITH A P < 0.001 AS WELL AS IN PATIENTS WITH AGE ABOVE 50 YEARS WITH A P VALUE = 0.008. BY APPLYING LOGISTIC REGRESSION ANALYSIS IT WAS REPORTED THAT THE H. PYLORI QPCR IS A SIGNIFICANT PREDICTOR TO THE ADENOCARCINOMA WITH OR = 1.025 (95 % CI: 1. 002-1.048), WITH SENSITIVITY OF 90 % AND SPECIFICITY OF 100 %. ADENOCARCINOMA PATIENTS HAD A SIGNIFICANTLY HIGHER MEAN AGE AND LEVELS OF H. PYLORI, BRAF, K-RAS, METHYLATED MGMT AND METHYLATED MLH1 THAN THOSE OF GASTRITIS PATIENTS. DNA SEQUENCE ANALYSIS OF BRAF (CODON 12) AND KRAS (CODON 600) HAD GENES MUTATION IN GASTRIC ADENOCARCINOMA VERSUS CHRONIC GASTRITIS. CONCLUSION: H. PYLORI MAY CAUSE EPIGENETIC CHANGES PREDISPOSING THE PATIENTS TO CANCER STOMACH. ESTIMATION OF H. PYLORI BY QPCR CAN BE A GOOD PREDICTOR TO ADENOCARCINOMA. BRAF AND KRAS GENES MUTATION WERE REVELED IN GASTRITIS AND ADENOCARCINOMA PATIENTS. 2016 19 6250 31 THE METHYLENETETRAHYDROFOLATE REDUCTASE 677C>T GENE POLYMORPHISM IS NOT ASSOCIATED WITH CHRONIC PLAQUE PSORIASIS. BACKGROUND: METHYLENETETRAHYDROFOLATE REDUCTASE (MTHFR) IS INVOLVED IN THE FORMATION OF METHYL DONORS, WHICH CONTRIBUTE TO DNA METHYLATION. DNA METHYLATION IS AN ESSENTIAL EPIGENETIC FEATURE PLAYING A CRITICAL ROLE IN GENE REGULATION AND CELLULAR DIFFERENTIATION. IN ADDITION, MTHFR ACTIVITY AFFECTS PLASMA HOMOCYSTEINE LEVELS. A FUNCTIONAL POLYMORPHISM IN THE MTHFR GENE (677C>T, RS1801133) LEADING TO REDUCED ENZYME ACTIVITY HAS BEEN ASSOCIATED WITH CHRONIC PLAQUE PSORIASIS IN A CHINESE POPULATION. THIS FINDING, HOWEVER, HAS NOT YET BEEN EITHER CONFIRMED OR REFUTED IN OTHER POPULATIONS. THE PURPOSE OF THE PRESENT STUDY WAS TO INVESTIGATE A HYPOTHESIZED ASSOCIATION BETWEEN THE MTHFR 677C>T POLYMORPHISM AND THE PRESENCE OF CHRONIC PLAQUE PSORIASIS IN A CAUCASIAN POPULATION. METHODS: GENOTYPES FOR THE MTHFR 677C>T POLYMORPHISM WERE DETERMINED IN 310 PATIENTS AND 247 CONTROL SUBJECTS. IN A SUBGROUP OF 33 PATIENTS AND 33 SEX- AND AGE-MATCHED CONTROL SUBJECTS, FASTING PLASMA HOMOCYSTEINE CONCENTRATIONS WERE DETERMINED BY HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY AND IMMUNOLOGICAL ASSAYS WERE USED FOR THE MEASUREMENT OF FOLATE AND VITAMIN B(12). RESULTS: PREVALENCE OF THE HOMOZYGOUS MTHFR 677TT GENOTYPE DID NOT SIGNIFICANTLY DIFFER BETWEEN PATIENTS AND CONTROLS (15.2% VS 11.7%, P = 0.24). MEAN PLASMA HOMOCYSTEINE CONCENTRATIONS WERE SIGNIFICANTLY HIGHER IN PSORIASIS PATIENTS THAN AMONG CONTROL SUBJECTS (13.5 +/- 5.3 MICROMOL/L VS 11.0 +/- 2.2 MICROMOL/L, P = 0.026). NO SIGNIFICANT DIFFERENCES BETWEEN EITHER MEAN PLASMA FOLATE OR VITAMIN B(12) CONCENTRATIONS WERE OBSERVED BETWEEN BOTH GROUPS. CONCLUSION: OUR DATA SUGGEST THAT THE MTHFR 677C>T GENE POLYMORPHISM IS NOT ASSOCIATED WITH CHRONIC PLAQUE PSORIASIS AMONG CAUCASIANS. 2008 20 4905 41 P16INK4A HYPERMETHYLATION IS ASSOCIATED WITH HEPATITIS VIRUS INFECTION, AGE, AND GENDER IN HEPATOCELLULAR CARCINOMA. PURPOSE: THE TUMOR SUPPRESSOR GENE P16INK4A IS MAINLY INACTIVATED BY AN EPIGENETIC CHANGE INVOLVING PROMOTER HYPERMETHYLATION IN HEPATOCARCINOGENESIS. THE POSSIBLE CLINICAL IMPACT OF P16INK4A METHYLATION AND THE POTENTIAL RISK FACTORS FOR THIS EPIGENETIC ALTERATION HAVE NOT BEEN THOROUGHLY INVESTIGATED. EXPERIMENTAL DESIGN: WE STUDIED THE METHYLATION STATUS AND MRNA AND PROTEIN EXPRESSION OF P16INK4A IN 50 HEPATOCELLULAR CARCINOMAS AND CORRESPONDING NONNEOPLASTIC LIVER LESIONS USING METHYLATION-SPECIFIC PCR, REVERSE TRANSCRIPTION-PCR, AND IMMUNOHISTOCHEMICAL TECHNIQUES. RESULTS: P16INK4A HYPERMETHYLATION WAS OBSERVED IN 58% (29 OF 50) OF THE HEPATOCELLULAR CARCINOMAS AND 16% (6 OF 38) OF THE CORRESPONDING CHRONIC HEPATITIS AND CIRRHOSIS TISSUE SAMPLES. P16INK4A METHYLATION WAS SIGNIFICANTLY ASSOCIATED WITH MRNA AND PROTEIN EXPRESSION (P <0.001 AND P=0.003, RESPECTIVELY). ALL OF THE P16INK4A-METHYLATED TUMORS WERE POSITIVE FOR HEPATITIS B VIRUS OR HEPATITIS C VIRUS MARKERS, BUT NONE OF THE VIRUS-NEGATIVE TUMORS EXHIBITED P16INK4A METHYLATION (P=0.006). THE FREQUENCY OF P16INK4A HYPERMETHYLATION TENDED TO BE HIGHER IN HEPATITIS C VIRUS-RELATED TUMORS (23 OF 32, 72%) THAN IN HEPATITIS B VIRUS-RELATED TUMORS (6 OF 13, 46%; P=0.1). ABERRANT METHYLATION OF P16INK4A WAS ALSO RELATED SIGNIFICANTLY TO INCREASING AGE, FEMALE GENDER, AND NORMAL LEVELS OF SERUM PIVKA-II (P=0.02, 0.04, AND 0.04, RESPECTIVELY). NO STATISTICALLY SIGNIFICANT DIFFERENCE IN SURVIVAL WAS OBSERVED BETWEEN PATIENTS WITH P16INK4A HYPERMETHYLATION AND THOSE WITHOUT. CONCLUSIONS: OUR OBSERVATIONS SUGGEST THAT P16INK4A HYPERMETHYLATION MAY CONTRIBUTE TO HEPATOCARCINOGENESIS FROM AN EARLY STAGE AND THAT MULTIPLE RISK FACTORS, SUCH AS VIRAL INFECTIONS, AGE, AND GENDER, MAY BE ASSOCIATED WITH P16INK4A HYPERMETHYLATION IN HEPATOCARCINOGENESIS. 2004