1 2564 151 EPIGENETICS INSIGHTS INTO CHRONIC PAIN: DNA HYPOMETHYLATION IN FIBROMYALGIA-A CONTROLLED PILOT-STUDY. TO EVALUATE CHANGES IN DNA METHYLATION PROFILES IN PATIENTS WITH FIBROMYALGIA (FM) COMPARED TO MATCHED HEALTHY CONTROLS (HCS). ALL INDIVIDUALS UNDERWENT FULL CLINICAL AND NEUROPHYSIOLOGICAL ASSESSMENT BY CORTICAL EXCITABILITY (CE) PARAMETERS MEASURED BY TRANSCRANIAL MAGNETIC STIMULATION. DNA FROM THE PERIPHERAL BLOOD OF PATIENTS WITH FM (N = 24) AND HC (N = 24) WERE ASSESSED USING THE ILLUMINA-HUMANMETHYLATION450 BEADCHIPS. WE IDENTIFIED 1610 DIFFERENTIALLY METHYLATED POSITIONS (DMPS) IN PATIENTS WITH FM DISPLAYING A NONRANDOM DISTRIBUTION IN REGIONS OF THE GENOME. SIXTY-NINE PERCENT OF DMP IN FM WERE HYPOMETHYLATED COMPARED TO HC. DIFFERENTIALLY METHYLATED POSITIONS WERE ENRICHED IN 5 GENOMIC REGIONS (1P34; 6P21; 10Q26; 17Q25; 19Q13). THE FUNCTIONAL CHARACTERIZATION OF 960 GENES RELATED TO DMPS REVEALED AN ENRICHMENT FOR MAPK SIGNALING PATHWAY (N = 18 GENES), REGULATION OF ACTIN CYTOSKELETON (N = 15 GENES), AND FOCAL ADHESION (N = 13 GENES). A GENE-GENE INTERACTION NETWORK ENRICHMENT ANALYSIS REVEALED THE PARTICIPATION OF DNA REPAIR PATHWAYS, MITOCHONDRIA-RELATED PROCESSES, AND SYNAPTIC SIGNALING. EVEN THOUGH DNA WAS EXTRACTED FROM PERIPHERAL BLOOD, THIS SET OF GENES WAS ENRICHED FOR DISORDERS SUCH AS SCHIZOPHRENIA, MOOD DISORDERS, BULIMIA, HYPERPHAGIA, AND OBESITY. REMARKABLY, THE HIERARCHICAL CLUSTERIZATION BASED ON THE METHYLATION LEVELS OF THE 1610 DMPS SHOWED AN ASSOCIATION WITH NEUROPHYSIOLOGICAL MEASUREMENTS OF CE IN FM AND HC. FIBROMYALGIA HAS A HYPOMETHYLATION DNA PATTERN, WHICH IS ENRICHED IN GENES IMPLICATED IN STRESS RESPONSE AND DNA REPAIR/FREE RADICAL CLEARANCE. THESE CHANGES OCCURRED PARALLEL TO CHANGES IN CE PARAMETERS. NEW EPIGENETIC INSIGHTS INTO THE PATHOPHYSIOLOGY OF FM MAY PROVIDE THE BASIS FOR THE DEVELOPMENT OF BIOMARKERS OF THIS DISORDER. 2017 2 2262 36 EPIGENETIC PROFILING IN CHRONIC LYMPHOCYTIC LEUKEMIA REVEALS NOVEL METHYLATION TARGETS. CPG ISLAND METHYLATION IS AN EPIGENETIC ALTERATION THAT CONTRIBUTES TO TUMORIGENESIS BY TRANSCRIPTIONAL INACTIVATION OF GENES. LITTLE IS KNOWN ABOUT THE OVERALL LEVELS OF CPG ISLAND METHYLATION IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). TO PROVIDE A BASELINE ESTIMATE OF GLOBAL ABERRANT METHYLATION AND IDENTIFY TARGET SEQUENCES FOR ADDITIONAL INVESTIGATION, WE PERFORMED RESTRICTION LANDMARK GENOMIC SCANNING ON 10 CLL SAMPLES. TWO METHYLATION-SENSITIVE LANDMARK ENZYMES WERE USED (NOTI AND ASCI), ALLOWING ASSESSMENT OF OVER 3000 CPG ISLANDS IN EACH SAMPLE. TUMOR-DERIVED RESTRICTION LANDMARK GENOMIC SCANNING PROFILES WERE COMPARED WITH PROFILES FROM CD19-SELECTED B CELLS FROM NORMAL VOLUNTEERS AND MATCHED NORMAL NEUTROPHILS FROM 4 CLL PATIENTS. WE FOUND 2.5-8.1% (MEAN 4.8%) OF THE CPG ISLANDS IN CLL SAMPLES WERE ABERRANTLY METHYLATED COMPARED WITH CONTROLS, AND THE METHYLATION EVENTS HAD A NONRANDOM DISTRIBUTION (P < 0.0001). FURTHERMORE, WE IDENTIFIED 193 ABERRANTLY METHYLATED SEQUENCES, OF WHICH 93% HAVE CPG ISLAND CHARACTERISTICS AND 90% HAVE HOMOLOGY TO GENES OR EXPRESSED SEQUENCES. ONE SUCH GENE, THE G PROTEIN-COUPLED METABOTROPIC GLUTAMATE RECEPTOR 7 (GRM7), POSSIBLY INHIBITS CYCLIC AMP SIGNALING IN THE INDUCTION OF APOPTOSIS. BISULFITE SEQUENCING OF GRM7 CONFIRMED EXTENSIVE CPG ISLAND METHYLATION, AND TREATMENT WITH 5-AZA-2'-DEOXYCYTIDINE (DECITABINE) RESULTED IN UP-REGULATED EXPRESSION OF SEVERAL GENES IN VITRO WITH CONCURRENT CELLULAR DEPLETION OF DNMT1 PROTEIN. OUR DUAL-ENZYME GLOBAL METHYLATION STUDY SHOWS THAT CLL IS CHARACTERIZED BY WIDESPREAD NONRANDOM CPG ISLAND METHYLATION SIMILAR TO OTHER TUMORS AND PROVIDES A PANEL OF NOVEL METHYLATION TARGETS THAT CAN BE USED IN LARGER STUDIES DESIGNED TO ASSESS IMPACT ON DISEASE PROGRESSION AND SURVIVAL. 2004 3 1424 28 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 4 249 38 ADVANCED AGING PHENOTYPE IS REVEALED BY EPIGENETIC MODIFICATIONS IN RAT LIVER AFTER IN UTERO MALNUTRITION. ADVERSE ENVIRONMENTAL EXPOSURES OF MOTHERS DURING FETAL PERIOD PREDISPOSE OFFSPRING TO A RANGE OF AGE-RELATED DISEASES EARLIER IN LIFE. HERE, WE SET TO DETERMINE WHETHER A DEREGULATED EPIGENETIC PATTERN IS SIMILAR IN YOUNG ANIMALS WHOSE MOTHERS' NUTRITION WAS MODULATED DURING FETAL GROWTH TO THAT ACQUIRED DURING NORMAL AGING IN ANIMALS. USING A RODENT MODEL OF MATERNAL UNDERNUTRITION (UN) OR OVERNUTRITION (ON), WE EXAMINED CYTOSINE METHYLATION PROFILES OF LIVER FROM YOUNG FEMALE OFFSPRING AND COMPARED THEM TO AGE-MATCHED YOUNG CONTROLS AND AGED (20-MONTH-OLD) ANIMALS. HELP-TAGGING, A GENOMEWIDE RESTRICTION ENZYME AND SEQUENCING ASSAY DEMONSTRATES THAT FETAL EXPOSURE TO TWO DIFFERENT MATERNAL DIETS IS ASSOCIATED WITH NONRANDOM DYSREGULATION OF METHYLATION LEVELS WITH PROFILES SIMILAR TO THOSE SEEN IN NORMAL AGING ANIMALS AND OCCUR IN REGIONS MAPPED TO GENES RELEVANT TO METABOLIC DISEASES AND AGING. FUNCTIONAL CONSEQUENCES WERE ASSESSED BY GENE EXPRESSION AT 9 WEEKS OLD WITH MORE SIGNIFICANT CHANGES AT 6 MONTHS OF AGE. EARLY DEVELOPMENTAL EXPOSURES TO UNFAVORABLE MATERNAL DIETS RESULT IN ALTERED METHYLATION PROFILES AND TRANSCRIPTIONAL DYSREGULATION IN PRKCB, PC, NCOR2, AND SMAD3 THAT IS ALSO SEEN WITH NORMAL AGING. THESE NOTCH PATHWAY AND LIPOGENESIS GENES MAY BE USEFUL FOR PREDICTION OF LATER SUSCEPTIBILITY TO CHRONIC DISEASE. 2016 5 6613 39 ULTRADEEP BISULFITE SEQUENCING ANALYSIS OF DNA METHYLATION PATTERNS IN MULTIPLE GENE PROMOTERS BY 454 SEQUENCING. WE DEVELOPED A NOVEL APPROACH FOR CONDUCTING MULTISAMPLE, MULTIGENE, ULTRADEEP BISULFITE SEQUENCING ANALYSIS OF DNA METHYLATION PATTERNS IN CLINICAL SAMPLES. A MASSIVELY PARALLEL SEQUENCING-BY-SYNTHESIS METHOD (454 SEQUENCING) WAS USED TO DIRECTLY SEQUENCE >100 BISULFITE PCR PRODUCTS IN A SINGLE SEQUENCING RUN WITHOUT SUBCLONING. WE SHOWED THE UTILITY, ROBUSTNESS, AND SUPERIORITY OF THIS APPROACH BY ANALYZING METHYLATION IN 25 GENE-RELATED CPG RICH REGIONS FROM >40 CASES OF PRIMARY CELLS, INCLUDING NORMAL PERIPHERAL BLOOD LYMPHOCYTES, ACUTE LYMPHOBLASTIC LEUKEMIA (ALL), CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), FOLLICULAR LYMPHOMA (FL), AND MANTLE CELL LYMPHOMA (MCL). A TOTAL OF 294,631 SEQUENCES WAS GENERATED WITH AN AVERAGE READ LENGTH OF 131 BP. ON AVERAGE, >1,600 INDIVIDUAL SEQUENCES WERE GENERATED FOR EACH PCR AMPLICON FAR BEYOND THE FEW CLONES (<20) TYPICALLY ANALYZED BY TRADITIONAL BISULFITE SEQUENCING. COMPREHENSIVE ANALYSIS OF CPG METHYLATION PATTERNS AT A SINGLE DNA MOLECULE LEVEL USING CLUSTERING ALGORITHMS REVEALED DIFFERENTIAL METHYLATION PATTERNS BETWEEN DISEASES. A SIGNIFICANT INCREASE IN METHYLATION WAS DETECTED IN ALL AND FL SAMPLES COMPARED WITH CLL AND MCL. FURTHERMORE, A PROGRESSIVE SPREADING OF METHYLATION WAS DETECTED FROM THE PERIPHERY TOWARD THE CENTER OF SELECT CPG ISLANDS IN THE ALL AND FL SAMPLES. THE ULTRADEEP SEQUENCING ALSO ALLOWED SIMULTANEOUS ANALYSIS OF GENETIC AND EPIGENETIC DATA AND REVEALED AN ASSOCIATION BETWEEN A SINGLE NUCLEOTIDE POLYMORPHISM AND THE METHYLATION PRESENT IN THE LRP1B PROMOTER. THIS NEW GENERATION OF METHYLOME SEQUENCING WILL PROVIDE DIGITAL PROFILES OF ABERRANT DNA METHYLATION FOR INDIVIDUAL HUMAN CANCERS AND OFFERS A ROBUST METHOD FOR THE EPIGENETIC CLASSIFICATION OF TUMOR SUBTYPES. 2007 6 3062 39 GENOME-WIDE DNA METHYLATION ANALYSIS REVEALS NOVEL EPIGENETIC CHANGES IN CHRONIC LYMPHOCYTIC LEUKEMIA. WE CONDUCTED A GENOME-WIDE DNA METHYLATION ANALYSIS IN CD19 (+) B-CELLS FROM CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) PATIENTS AND NORMAL CONTROL SAMPLES USING REDUCED REPRESENTATION BISULFITE SEQUENCING (RRBS). THE METHYLATION STATUS OF 1.8-2.3 MILLION CPGS IN THE CLL GENOME WAS DETERMINED; ABOUT 45% OF THESE CPGS WERE LOCATED IN MORE THAN 23,000 CPG ISLANDS (CGIS). WHILE GLOBAL CPG METHYLATION WAS SIMILAR BETWEEN CLL AND NORMAL B-CELLS, 1764 GENE PROMOTERS WERE IDENTIFIED AS BEING DIFFERENTIALLY METHYLATED IN AT LEAST ONE CLL SAMPLE WHEN COMPARED WITH NORMAL B-CELL SAMPLES. NINETEEN PERCENT OF THE DIFFERENTIALLY METHYLATED GENES WERE INVOLVED IN TRANSCRIPTIONAL REGULATION. ABERRANT HYPERMETHYLATION WAS FOUND IN ALL HOX GENE CLUSTERS AND A SIGNIFICANT NUMBER OF WNT SIGNALING PATHWAY GENES. HYPOMETHYLATION OCCURRED MORE FREQUENTLY IN THE GENE BODY INCLUDING INTRONS, EXONS, AND 3'-UTRS IN CLL. THE NFATC1 P2 PROMOTER AND FIRST INTRON WAS FOUND TO BE HYPOMETHYLATED AND CORRELATED WITH UPREGULATION OF BOTH NFATC1 RNA AND PROTEIN EXPRESSION LEVELS IN CLL SUGGESTING THAT AN EPIGENETIC MECHANISM IS INVOLVED IN THE CONSTITUTIVE ACTIVATION OF NFAT ACTIVITY IN CLL CELLS. THIS COMPREHENSIVE DNA METHYLATION ANALYSIS WILL FURTHER OUR UNDERSTANDING OF THE EPIGENETIC CONTRIBUTION TO CELLULAR DYSFUNCTION IN CLL. 2012 7 1433 30 DIFFERENTIAL GENOME-WIDE ARRAY-BASED METHYLATION PROFILES IN PROGNOSTIC SUBSETS OF CHRONIC LYMPHOCYTIC LEUKEMIA. GLOBAL HYPOMETHYLATION AND REGIONAL HYPERMETHYLATION ARE WELL-KNOWN EPIGENETIC FEATURES OF CANCER; HOWEVER, IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), STUDIES ON GENOME-WIDE EPIGENETIC MODIFICATIONS ARE LIMITED. HERE, WE ANALYZED THE GLOBAL METHYLATION PROFILES IN CLL, BY APPLYING HIGH-RESOLUTION METHYLATION MICROARRAYS (27,578 CPG SITES) TO 23 CLL SAMPLES, BELONGING TO THE IMMUNOGLOBULIN HEAVY-CHAIN VARIABLE (IGHV) MUTATED (FAVORABLE) AND IGHV UNMUTATED/IGHV3-21 (POOR-PROGNOSTIC) SUBSETS. OVERALL, RESULTS DEMONSTRATED SIGNIFICANT DIFFERENCES IN METHYLATION PATTERNS BETWEEN THESE SUBGROUPS. SPECIFICALLY, IN IGHV UNMUTATED CLL, WE IDENTIFIED METHYLATION OF 7 KNOWN OR CANDIDATE TUMOR SUPPRESSOR GENES (EG, VHL, ABI3, AND IGSF4) AS WELL AS 8 UNMETHYLATED GENES INVOLVED IN CELL PROLIFERATION AND TUMOR PROGRESSION (EG, ADORA3 AND PRF1 ENHANCING THE NUCLEAR FACTOR-KAPPAB AND MITOGEN-ACTIVATED PROTEIN KINASE PATHWAYS, RESPECTIVELY). IN CONTRAST, THESE LATTER GENES WERE SILENCED BY METHYLATION IN IGHV MUTATED PATIENTS. THE ARRAY DATA WERE VALIDATED FOR SELECTED GENES USING METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION, QUANTITATIVE REVERSE TRANSCRIPTASE-POLYMERASE CHAIN REACTION, AND BISULFITE SEQUENCING. FINALLY, THE SIGNIFICANCE OF DNA METHYLATION IN REGULATING GENE PROMOTERS WAS SHOWN BY REINDUCING 4 METHYLATED TUMOR SUPPRESSOR GENES (EG, VHL AND ABI3) IN IGHV UNMUTATED SAMPLES USING THE METHYL-INHIBITOR 5-AZA-2'-DEOXYCYTIDINE. TAKEN TOGETHER, OUR DATA FOR THE FIRST TIME REVEAL DIFFERENCES IN GLOBAL METHYLATION PROFILES BETWEEN PROGNOSTIC SUBSETS OF CLL, WHICH MAY UNFOLD EPIGENETIC SILENCING MECHANISMS INVOLVED IN CLL PATHOGENESIS. 2010 8 3138 42 GLOBAL DNA METHYLATION PROFILING REVEALS NEW INSIGHTS INTO EPIGENETICALLY DEREGULATED PROTEIN CODING AND LONG NONCODING RNAS IN CLL. BACKGROUND: METHYL-CPG-BINDING DOMAIN PROTEIN ENRICHED GENOME-WIDE SEQUENCING (MBD-SEQ) IS A ROBUST AND POWERFUL METHOD FOR ANALYZING METHYLATED CPG-RICH REGIONS WITH COMPLETE GENOME-WIDE COVERAGE. IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), THE ROLE OF CPG METHYLATED REGIONS ASSOCIATED WITH TRANSCRIBED LONG NONCODING RNAS (LNCRNA) AND REPETITIVE GENOMIC ELEMENTS ARE POORLY UNDERSTOOD. BASED ON MBD-SEQ, WE CHARACTERIZED THE GLOBAL METHYLATION PROFILE OF HIGH CPG-RICH REGIONS IN DIFFERENT CLL PROGNOSTIC SUBGROUPS BASED ON IGHV MUTATIONAL STATUS. RESULTS: OUR STUDY IDENTIFIED 5800 HYPERMETHYLATED AND 12,570 HYPOMETHYLATED CLL-SPECIFIC DIFFERENTIALLY METHYLATED GENES (CLLDMGS) COMPARED TO NORMAL CONTROLS. FROM CLLDMGS, 40 % OF HYPERMETHYLATED AND 60 % OF HYPOMETHYLATED GENES WERE MAPPED TO NONCODING RNAS. IN ADDITION, WE FOUND THAT THE MAJOR REPETITIVE ELEMENTS SUCH AS SHORT INTERSPERSED ELEMENTS (SINE) AND LONG INTERSPERSED ELEMENTS (LINE) HAVE A HIGH PERCENTAGE OF CLLDMRS (DIFFERENTIALLY METHYLATED REGIONS) IN IGHV SUBGROUPS COMPARED TO NORMAL CONTROLS. FINALLY, TWO NOVEL LNCRNAS (HYPERMETHYLATED CRNDE AND HYPOMETHYLATED AC012065.7) WERE VALIDATED IN AN INDEPENDENT CLL SAMPLE COHORT (48 SAMPLES) COMPARED WITH 6 NORMAL SORTED B CELL SAMPLES USING QUANTITATIVE PYROSEQUENCING ANALYSIS. THE METHYLATION LEVELS SHOWED AN INVERSE CORRELATION TO GENE EXPRESSION LEVELS ANALYZED BY REAL-TIME QUANTITATIVE PCR. NOTABLY, SURVIVAL ANALYSIS REVEALED THAT HYPERMETHYLATION OF CRNDE AND HYPOMETHYLATION OF AC012065.7 CORRELATED WITH AN INFERIOR OUTCOME. CONCLUSIONS: THUS, OUR COMPREHENSIVE METHYLATION ANALYSIS BY MBD-SEQ PROVIDED NOVEL HYPER AND HYPOMETHYLATED LONG NONCODING RNAS, REPETITIVE ELEMENTS, ALONG WITH PROTEIN CODING GENES AS POTENTIAL EPIGENETIC-BASED CLL-SIGNATURE GENES INVOLVED IN DISEASE PATHOGENESIS AND PROGNOSIS. 2016 9 2133 21 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 10 1969 36 EPIGENETIC ALTERATIONS AND AN INCREASED FREQUENCY OF MICRONUCLEI IN WOMEN WITH FIBROMYALGIA. FIBROMYALGIA (FM), CHARACTERIZED BY CHRONIC WIDESPREAD PAIN, FATIGUE, AND COGNITIVE/MOOD DISTURBANCES, LEADS TO REDUCED WORKPLACE PRODUCTIVITY AND INCREASED HEALTHCARE EXPENSES. TO DETERMINE IF ACQUIRED EPIGENETIC/GENETIC CHANGES ARE ASSOCIATED WITH FM, WE COMPARED THE FREQUENCY OF SPONTANEOUSLY OCCURRING MICRONUCLEI (MN) AND GENOME-WIDE METHYLATION PATTERNS IN WOMEN WITH FM (N = 10) TO THOSE SEEN IN COMPARABLY AGED HEALTHY CONTROLS (N = 42 (MN); N = 8 (METHYLATION)). THE MEAN (SD) MN FREQUENCY OF WOMEN WITH FM (51.4 (21.9)) WAS SIGNIFICANTLY HIGHER THAN THAT OF CONTROLS (15.8 (8.5)) (CHI (2) = 45.552; DF = 1; P = 1.49 X 10(-11)). SIGNIFICANT DIFFERENCES (N = 69 SITES) IN METHYLATION PATTERNS WERE OBSERVED BETWEEN CASES AND CONTROLS CONSIDERING A 5% FALSE DISCOVERY RATE. THE MAJORITY OF DIFFERENTIALLY METHYLATED (DM) SITES (91%) WERE ATTRIBUTABLE TO INCREASED VALUES IN THE WOMEN WITH FM. THE DM SITES INCLUDED SIGNIFICANT BIOLOGICAL CLUSTERS INVOLVED IN NEURON DIFFERENTIATION/NERVOUS SYSTEM DEVELOPMENT, SKELETAL/ORGAN SYSTEM DEVELOPMENT, AND CHROMATIN COMPACTION. GENES ASSOCIATED WITH DM SITES WHOSE FUNCTION HAS PARTICULAR RELEVANCE TO FM INCLUDED BDNF, NAT15, HDAC4, PRKCA, RTN1, AND PRKG1. RESULTS SUPPORT THE NEED FOR FUTURE RESEARCH TO FURTHER EXAMINE THE POTENTIAL ROLE OF EPIGENETIC AND ACQUIRED CHROMOSOMAL ALTERATIONS AS A POSSIBLE BIOLOGICAL MECHANISM UNDERLYING FM. 2013 11 2261 25 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 12 157 30 ABERRANT METHYLATION OF TUMOUR SUPPRESSOR GENE ADAM12 IN CHRONIC LYMPOCYTIC LEUKEMIA PATIENTS: APPLICATION OF METHYLATION SPECIFIC-PCR TECHNIQUE. OBJECTIVE: CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS A COMMON LEUKEMIA AMONG CAUCASIANS BUT RARE IN ASIANS POPULATION. WE POSTULATED THAT ABERRANT METHYLATION EITHER HYPERMETHYLATION OR PARTIAL METHYLATION MIGHT BE ONE OF THE SILENCING MECHANISMS THAT INACTIVATES THE TUMOUR SUPPRESSOR GENES IN CLL. THIS STUDY AIMED TO COMPARE THE METHYLATION STATUS OF TUMOUR SUPPRESSOR GENE, ADAM12, AMONG CLL PATIENTS AND NORMAL INDIVIDUALS. WE ALSO EVALUATED THE ASSOCIATION BETWEEN METHYLATION OF ADAM12 AND CLINICAL AND DEMOGRAPHIC CHARACTERISTICS OF THE PARTICIPANTS. METHODS: A TOTAL OF 25 CLL PATIENTS AND 25 NORMAL INDIVIDUALS WERE RECRUITED IN THIS STUDY. THE METHYLATION STATUS OF ADAM12 WAS DETERMINED USING METHYLATION-SPECIFIC PCR (MSP); WHEREAS, DNA SEQUENCING METHOD WAS APPLIED FOR VALIDATION OF THE MSP RESULTS. RESULTS: AMONG CLL PATIENTS, 12 (48%) WERE PARTIALLY METHYLATED AND 13 (52%) WERE UNMETHYLATED. MEANWHILE, 5 (20%) AND 20 (80.6%) OF HEALTHY INDIVIDUALS WERE PARTIALLY METHYLATED AND UNMETHYLATED, RESPECTIVELY. THERE WAS A STATISTICALLY SIGNIFICANT ASSOCIATION BETWEEN THE STATUS OF METHYLATION AT ADAM12 AND THE PRESENCE OF CLL (P=0.037). CONCLUSION: THE ABERRANT METHYLATION OF ADAM12 FOUND IN THIS STUDY USING MSP ASSAY MAY PROVIDE NEW EXPOSURE TO CLL THAT MAY IMPROVE THE GAPS INVOLVED IN GENETIC EPIGENETIC STUDY IN CLL. 2021 13 4432 26 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 14 2438 31 EPIGENETIC SILENCING OF THE CIRCADIAN CLOCK GENE CRY1 IS ASSOCIATED WITH AN INDOLENT CLINICAL COURSE IN CHRONIC LYMPHOCYTIC LEUKEMIA. DISRUPTION OF CIRCADIAN RHYTHM IS BELIEVED TO PLAY A CRITICAL ROLE IN CANCER DEVELOPMENT. CRYPTOCHROME 1 (CRY1) IS A CORE COMPONENT OF THE MAMMALIAN CIRCADIAN CLOCK AND WE HAVE PREVIOUSLY SHOWN ITS DEREGULATED EXPRESSION IN A SUBGROUP OF PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). USING REAL-TIME RT-PCR IN A COHORT OF 76 CLL PATIENTS AND 35 NORMAL BLOOD DONORS WE NOW DEMONSTRATE THAT DIFFERENTIAL CRY1 MRNA EXPRESSION IN HIGH-RISK (HR) CD38+/IMMUNOGLOBULIN VARIABLE HEAVY CHAIN GENE (IGVH) UNMUTATED PATIENTS AS COMPARED TO LOW-RISK (LR) CD38-/IGVH MUTATED PATIENTS CAN BE ATTRIBUTED TO DOWN-MODULATION OF CRY1 IN LR CLL CASES. ANALYSIS OF THE DNA METHYLATION PROFILE OF THE CRY1 PROMOTER IN A SUBGROUP OF 57 PATIENTS REVEALED THAT CRY1 EXPRESSION IN LR CLL CELLS IS SILENCED BY ABERRANT PROMOTER CPG ISLAND HYPERMETHYLATION. THE METHYLATION PATTERN OF THE CRY1 PROMOTER PROVED TO HAVE HIGH PROGNOSTIC IMPACT IN CLL WHERE ABERRANT PROMOTER METHYLATION PREDICTED A FAVOURABLE OUTCOME. CRY1 MRNA TRANSCRIPT LEVELS DID NOT CHANGE OVER TIME IN THE MAJORITY OF PATIENTS WHERE SEQUENTIAL SAMPLES WERE AVAILABLE FOR ANALYSIS. WE ALSO COMPARED THE CRY1 EXPRESSION IN CLL WITH OTHER LYMPHOID MALIGNANCIES AND OBSERVED EPIGENETIC SILENCING OF CRY1 IN A PATIENT WITH B CELL ACUTE LYMPHOBLASTIC LEUKEMIA (B-ALL). 2012 15 411 39 ANALYSIS OF GENOME-WIDE DNA METHYLATION PATTERNS IN OBESITY. OBESITY IS A CHRONIC AND COMPLEX PSYCHOSOMATIC DISEASE THAT IS BECOMING INCREASINGLY PREVALENT WORLDWIDE. THIS STUDY AIMED TO ANALYZE WHOLE METHYLATION PROFILES TO UNCOVER THE EPIGENETIC MECHANISMS ASSOCIATED WITH OBESITY. DNA METHYLATION PROFILES IN BLOOD SAMPLES FROM PATIENTS WITH OBESITY AND NORMAL CONTROLS WERE STUDIED USING THE ILLUMINA 850 K METHYLATION MICROARRAY. THE DIAGNOSTIC VALUE OF THE DIFFERENTIALLY METHYLATED GENES WAS DETERMINED USING RECEIVER OPERATING CHARACTERISTIC (ROC) ANALYSIS. THE EXPRESSION OF SELECTED CANDIDATE GENES WAS VERIFIED USING REVERSE TRANSCRIPTION QUANTITATIVE POLYMERASE CHAIN REACTION (RT-QPCR) AND PYROSEQUENCING. A TOTAL OF 9,371 SIGNIFICANTLY DIFFERENTIALLY METHYLATED SITES (7,974 HYPERMETHYLATED SITES AND 1,397 HYPOMETHYLATED SITES) WERE IDENTIFIED IN 4,571 GENES. A DIFFERENCE IN THE DISTRIBUTION OF DIFFERENTIALLY METHYLATED SITES (HYPERMETHYLATED AND HYPOMETHYLATED) IN BOTH GENE STRUCTURES AND CPG ISLANDS WAS OBSERVED. A TOTAL OF 114 KEY DIFFERENTIALLY METHYLATED SITES WERE IDENTIFIED IN THE CPG ISLANDS. ROC RESULTS INDICATED THAT INHIBIN SUBUNIT BETA B (INHBB), HOMEOBOX A9 (HOXA9), TROPONIN T3 (TNNT3), CYCLIC ADENOSINE MONOPHOSPHATE (CAMP)-RESPONSIVE ELEMENT BINDING PROTEIN (CREB)-REGULATED TRANSCRIPTION COACTIVATOR 1 (CRTC1) AND ZINC FINGER AND BTB DOMAIN-CONTAINING 7 B (ZBTB7B) COULD DISCRIMINATE PATIENTS WITH OBESITY FROM NORMAL CONTROLS. RT-QPCR RESULTS OF CRTC1 AND ZBTB7B WERE CONSISTENT WITH OUR METHYLATION PROFILE RESULTS. THE PYROSEQUENCING RESULTS SHOWED THAT THE METHYLATION LEVELS OF CRTC1 CPG SITES (CPG1 AND CPG2-CG11660071) AND INHBB CPG SITES (CPG2) WERE SIGNIFICANTLY CHANGED IN PATIENTS WITH OBESITY COMPARED WITH NORMAL CONTROLS, WHICH WAS CONSISTENT WITH OUR DNA METHYLATION PROFILE RESULTS. OUR STUDY PROVIDES NEW INSIGHTS INTO THE PATHOLOGICAL MECHANISM OF OBESITY. 2021 16 2678 29 EVALUATION OF A PROGNOSTIC EPIGENETIC CLASSIFICATION SYSTEM IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS. BACKGROUND: METHYLATION AT 5 CPG SITES WAS PREVIOUSLY SHOWN TO CLASSIFY CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) INTO 3 PROGNOSTIC SUBGROUPS. HERE, WE AIMED TO VALIDATE THE MARKER SET IN AN ADDITIONAL COHORT AND TO EVALUATE ITS CLINICAL UTILITY FOR CLL PATIENT STRATIFICATION. METHODS: WE EVALUATED THIS EPIGENETIC MARKER SET IN 79 GERMAN PATIENTS USING BISULFITE TREATMENT FOLLOWED BY PYROSEQUENCING AND CLASSIFICATION USING A SUPPORT VECTOR MACHINE-LEARNING TOOL. RESULTS: THE N-CLL, I-CLL, AND M-CLL CLASSIFICATION WAS DETECTED IN 28 (35%), 10 (13%), AND 41 (51%) PATIENTS, RESPECTIVELY. EPIGENETIC GROUPING WAS ASSOCIATED WITH IGHV MUTATIONAL STATUS (P = 2 X 10(-12)), ISOLATED DEL13Q (P = 9 X 10(-6)), DEL17P (P = .015), COMPLEX KARYOTYPE (P = .005), VH-USAGE, AND CLINICAL OUTCOME AS TIME TO FIRST TREATMENT (P = 1.4 X 10(-12)) AND OVERALL SURVIVAL (P = .003). MULTIVARIATE COX REGRESSION ANALYSIS IDENTIFIED N-CLL AS A FACTOR FOR EARLIER TREATMENT HAZARD RATIO (HR), 6.3 (95% CONFIDENCE INTERVAL [CI] 2.4-16.4; P = .0002) COMPARED TO IGHV MUTATIONAL STATUS (HR 4.6, 95% CI 1.9-11.3, P = .0008). IN ADDITION, WHEN COMPARING THE PROGNOSTIC VALUE OF THE EPIGENETIC CLASSIFICATION SYSTEM WITH THE IGHV CLASSIFICATION, EPIGENETIC GROUPING PERFORMED BETTER COMPARED TO IGHV MUTATIONAL STATUS USING KAPLAN-MEIER ESTIMATION AND ALLOWED THE IDENTIFICATION OF A THIRD, INTERMEDIATE (I-CLL) GROUP. THUS, OUR STUDY CONFIRMED THE PROGNOSTIC VALUE OF THE EPIGENETIC MARKER SET FOR PATIENT STRATIFICATION IN ROUTINE CLINICAL DIAGNOSTICS. 2022 17 494 27 ASSESSMENT OF PROMOTER METHYLATION IDENTIFIES PTCH AS A PUTATIVE TUMOR-SUPPRESSOR GENE IN HUMAN CLL. BACKGROUND: CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY A CLONAL ACCUMULATION OF NEOPLASTIC LYMPHOCYTES, INDICATING DISRUPTION OF APOPTOSIS. PATIENTS AND METHODS: DIFFERENTIAL METHYLATION HYBRIDIZATION ANALYSIS WAS PERFORMED TO IDENTIFY NOVEL TARGET GENES SILENCED BY CPG ISLAND METHYLATION IN PATIENTS WITH CLL. RESULTS: PATCHED (PTCH), A TUMOR-SUPPRESSOR GENE, WAS FOUND TO BE FREQUENTLY METHYLATED IN CLL SAMPLES COMPARED TO SAMPLES DERIVED FROM HEALTHY INDIVIDUALS. DE NOVO METHYLATION OF A CPG ISLAND REGION LOCATED UPSTREAM OF PTCH EXON 1 WAS CONFIRMED BY PYROSEQUENCING IN 17/37 (46%) OF PERIPHERAL BLOOD MONONUCLEAR CELLS OF PATIENTS WITH CLL, BUT IN NONE ISOLATED FROM SEVEN HEALTHY INDIVIDUALS. NO ASSOCIATION WAS FOUND BETWEEN PTCH HYPERMETHYLATION AND CURRENTLY USED PROGNOSTIC CLL FACTORS. CONCLUSION: OUR INVESTIGATION SUGGESTS THAT EPIGENETIC SILENCING OF PTCH IS A MECHANISM CONTRIBUTING TO CLL TUMORIGENESIS. 2016 18 3071 39 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 19 2639 29 EPIGENOMIC ANALYSIS DETECTS WIDESPREAD GENE-BODY DNA HYPOMETHYLATION IN CHRONIC LYMPHOCYTIC LEUKEMIA. WE HAVE EXTENSIVELY CHARACTERIZED THE DNA METHYLOMES OF 139 PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) WITH MUTATED OR UNMUTATED IGHV AND OF SEVERAL MATURE B-CELL SUBPOPULATIONS THROUGH THE USE OF WHOLE-GENOME BISULFITE SEQUENCING AND HIGH-DENSITY MICROARRAYS. THE TWO MOLECULAR SUBTYPES OF CLL HAVE DIFFERING DNA METHYLOMES THAT SEEM TO REPRESENT EPIGENETIC IMPRINTS FROM DISTINCT NORMAL B-CELL SUBPOPULATIONS. DNA HYPOMETHYLATION IN THE GENE BODY, TARGETING MOSTLY ENHANCER SITES, WAS THE MOST FREQUENT DIFFERENCE BETWEEN NAIVE AND MEMORY B CELLS AND BETWEEN THE TWO MOLECULAR SUBTYPES OF CLL AND NORMAL B CELLS. ALTHOUGH DNA METHYLATION AND GENE EXPRESSION WERE POORLY CORRELATED, WE IDENTIFIED GENE-BODY CPG DINUCLEOTIDES WHOSE METHYLATION WAS POSITIVELY OR NEGATIVELY ASSOCIATED WITH EXPRESSION. WE HAVE ALSO RECOGNIZED A DNA METHYLATION SIGNATURE THAT DISTINGUISHES NEW CLINICO-BIOLOGICAL SUBTYPES OF CLL. WE PROPOSE AN EPIGENOMIC SCENARIO IN WHICH DIFFERENTIAL METHYLATION IN THE GENE BODY MAY HAVE FUNCTIONAL AND CLINICAL IMPLICATIONS IN LEUKEMOGENESIS. 2012 20 5056 23 PHASE I TRIAL OF LOW DOSE DECITABINE TARGETING DNA HYPERMETHYLATION IN PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKAEMIA AND NON-HODGKIN LYMPHOMA: DOSE-LIMITING MYELOSUPPRESSION WITHOUT EVIDENCE OF DNA HYPOMETHYLATION. TARGETING ABERRANT DNA HYPERMETHYLATION IN CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL) AND NON-HODGKIN LYMPHOMA (NHL) WITH DECITABINE MAY REVERSE EPIGENETIC SILENCING IN B-CELL MALIGNANCIES. TWENTY PATIENTS WERE ENROLLED IN TWO PHASE I TRIALS TO DETERMINE THE MINIMUM EFFECTIVE PHARMACOLOGICAL DOSE OF DECITABINE IN PATIENTS WITH RELAPSED/REFRACTORY CLL (N = 16) AND NHL (N = 4). PATIENTS RECEIVED 1-3 CYCLES OF DECITABINE. DOSE-LIMITING TOXICITY (DLT) WAS OBSERVED IN 2 OF 4 CLL AND 2 OF 2 NHL PATIENTS RECEIVING DECITABINE AT 15 MG/M(2) PER D DAYS 1-10, CONSISTING OF GRADE 3-4 THROMBOCYTOPENIA AND HYPERBILIRUBINAEMIA. SIX PATIENTS WITH CLL RECEIVED DECITABINE AT 10 MG/M(2) PER D DAYS 1-10 WITHOUT DLT; HOWEVER, RE-EXPRESSION OF METHYLATED GENES OR CHANGES IN GLOBAL DNA METHYLATION WERE NOT OBSERVED. THEREFORE, A 5-DAY DECITABINE SCHEDULE WAS EXAMINED. WITH 15 MG/M(2) PER D DECITABINE DAYS 1-5, DLT OCCURRED IN 2 OF 6 CLL AND 2 OF 2 NHL PATIENTS, CONSISTING OF GRADE 3-4 NEUTROPENIA, THROMBOCYTOPENIA, AND FEBRILE NEUTROPENIA. EIGHT PATIENTS HAD STABLE DISEASE. IN 17 PATIENTS, THERE WERE NO SIGNIFICANT CHANGES IN GENOME-WIDE METHYLATION OR IN TARGET GENE RE-EXPRESSION. IN CONCLUSION, DOSE-LIMITING MYELOSUPPRESSION AND INFECTIOUS COMPLICATIONS PREVENTED DOSE ESCALATION OF DECITABINE TO LEVELS ASSOCIATED WITH CHANGES IN GLOBAL METHYLATION OR GENE RE-EXPRESSION IN CLL AND NHL. 2010