1 1424 95 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
2 2262 31 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 3062 37 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
4 2966 25 GENETIC AND EPIGENETIC PROFILING OF CLL DISEASE PROGRESSION REVEALS LIMITED SOMATIC EVOLUTION AND SUGGESTS A RELATIONSHIP TO MEMORY-CELL DEVELOPMENT. WE EXAMINED GENETIC AND EPIGENETIC CHANGES THAT OCCUR DURING DISEASE PROGRESSION FROM INDOLENT TO AGGRESSIVE FORMS OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) USING SERIAL SAMPLES FROM 27 PATIENTS. ANALYSIS OF DNA MUTATIONS GROUPED THE LEUKEMIA CASES INTO THREE CATEGORIES: EVOLVING (26%), EXPANDING (26%) AND STATIC (47%). THUS, APPROXIMATELY THREE-QUARTERS OF THE CLL CASES HAD LITTLE TO NO GENETIC SUBCLONAL EVOLUTION. HOWEVER, WE IDENTIFIED SIGNIFICANT RECURRENT DNA METHYLATION CHANGES DURING PROGRESSION AT 4752 CPGS ENRICHED FOR REGIONS NEAR POLYCOMB 2 REPRESSIVE COMPLEX (PRC2) TARGETS. PROGRESSION-ASSOCIATED CPGS NEAR THE PRC2 TARGETS UNDERGO METHYLATION CHANGES IN THE SAME DIRECTION DURING DISEASE PROGRESSION AS DURING NORMAL DEVELOPMENT FROM NAIVE TO MEMORY B CELLS. OUR STUDY SHOWS THAT CLL PROGRESSION DOES NOT TYPICALLY OCCUR VIA SUBCLONAL EVOLUTION, BUT THAT CERTAIN CPG SITES UNDERGO RECURRENT METHYLATION CHANGES. OUR RESULTS SUGGEST CLL PROGRESSION MAY INVOLVE DEVELOPMENTAL PROCESSES SHARED IN COMMON WITH THE GENERATION OF NORMAL MEMORY B CELLS.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
5 5210 21 PRENEOPLASTIC ALTERATIONS DEFINE CLL DNA METHYLOME AND PERSIST THROUGH DISEASE PROGRESSION AND THERAPY. MOST HUMAN CANCERS CONVERGE TO A DEREGULATED METHYLOME WITH REDUCED GLOBAL LEVELS AND ELEVATED METHYLATION AT SELECT CPG ISLANDS. TO INVESTIGATE THE EMERGENCE AND DYNAMICS OF THE CANCER METHYLOME, WE CHARACTERIZED GENOME-WIDE DNA METHYLATION IN PRE-NEOPLASTIC MONOCLONAL B CELL LYMPHOCYTOSIS (MBL) AND CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), INCLUDING SERIAL SAMPLES COLLECTED ACROSS DISEASE COURSE. WE DETECTED THE ABERRANT TUMOR-ASSOCIATED METHYLATION LANDSCAPE AT CLL DIAGNOSIS AND FOUND NO SIGNIFICANTLY DIFFERENTIALLY METHYLATED REGIONS IN THE HIGH-COUNT MBL-TO-CLL TRANSITION. PATIENT METHYLOMES SHOWED REMARKABLE STABILITY WITH NATURAL DISEASE AND POST-THERAPY PROGRESSION. SINGLE CLL CELLS WERE CONSISTENTLY ABERRANTLY METHYLATED, INDICATING A HOMOGENEOUS TRANSITION TO THE ALTERED EPIGENETIC STATE, AND A DISTINCT EXPRESSION PROFILE TOGETHER WITH MBL CELLS COMPARED TO NORMAL B CELLS. OUR LONGITUDINAL ANALYSIS REVEALS THE CANCER METHYLOME TO EMERGE EARLY, WHICH MAY PROVIDE A PLATFORM FOR SUBSEQUENT GENETICALLY-DRIVEN GROWTH DYNAMICS AND TOGETHER WITH ITS PERSISTENT PRESENCE SUGGESTS A CENTRAL ROLE IN THE NORMAL-TO-CANCER TRANSITION.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
6   59 31 A GENOME-WIDE SCREEN IDENTIFIES FREQUENTLY METHYLATED GENES IN HAEMATOLOGICAL AND EPITHELIAL CANCERS. BACKGROUND: GENETIC AS WELL AS EPIGENETIC ALTERATIONS ARE A HALLMARK OF BOTH EPITHELIAL AND HAEMATOLOGICAL MALIGNANCIES. HIGH THROUGHPUT SCREENS ARE REQUIRED TO IDENTIFY EPIGENETIC MARKERS THAT CAN BE USEFUL FOR DIAGNOSTIC AND PROGNOSTIC PURPOSES ACROSS MALIGNANCIES. RESULTS: HERE WE REPORT FOR THE FIRST TIME THE USE OF THE MIRA ASSAY (METHYLATED CPG ISLAND RECOVERY ASSAY) IN COMBINATION WITH GENOME-WIDE CPG ISLAND ARRAYS TO IDENTIFY EPIGENETIC MOLECULAR MARKERS IN CHILDHOOD ACUTE LYMPHOBLASTIC LEUKEMIA (ALL) ON A GENOME-WIDE SCALE. WE IDENTIFIED 30 GENES DEMONSTRATING METHYLATION FREQUENCIES OF > OR =25% IN CHILDHOOD ALL, NINE GENES SHOWED SIGNIFICANTLY DIFFERENT METHYLATION FREQUENCIES IN B VS T-ALL. FOR MAJORITY OF THE GENES EXPRESSION COULD BE RESTORED IN METHYLATED LEUKEMIA LINES AFTER TREATMENT WITH 5-AZADC. FORTY-FOUR PERCENT OF THE GENES REPRESENT TARGETS OF THE POLYCOMB COMPLEX. IN CHRONIC MYELOID LEUKEMIA (CML) TWO OF THE GENES, (TFAP2A AND EBF2), DEMONSTRATED INCREASED METHYLATION IN BLAST CRISIS COMPARED TO CHRONIC PHASE (P < 0.05). FURTHERMORE HYPERMETHYLATION OF AN AUTOPHAGY RELATED GENE ATG16L2 WAS ASSOCIATED WITH POORER PROGNOSIS IN TERMS OF MOLECULAR RESPONSE TO IMATINIB TREATMENT. LASTLY WE DEMONSTRATED THAT TEN OF THESE GENES WERE ALSO FREQUENTLY METHYLATED IN COMMON EPITHELIAL CANCERS. CONCLUSION: IN SUMMARY WE HAVE IDENTIFIED A LARGE NUMBER OF GENES SHOWING FREQUENT METHYLATION IN CHILDHOOD ALL, METHYLATION STATUS OF TWO OF THESE GENES IS ASSOCIATED WITH ADVANCED DISEASE IN CML AND METHYLATION STATUS OF ANOTHER GENE IS ASSOCIATED WITH PROGNOSIS. IN ADDITION A SUBSET OF THESE GENES MAY ACT AS EPIGENETIC MARKERS ACROSS HEMATOLOGICAL MALIGNANCIES AS WELL AS COMMON EPITHELIAL CANCERS.	2010	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
7 3896 36 LARGE-SCALE ANALYSIS OF DNA METHYLATION IN CHRONIC LYMPHOCYTIC LEUKEMIA. AIMS: B-CELL CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS A HETEROGENEOUS MALIGNANCY THAT CLINICALLY RANGES FROM INDOLENT TO RAPIDLY PROGRESSIVE. CLL, LIKE OTHER CANCERS, CAN BE AFFECTED BY EPIGENETIC ALTERATIONS. MATERIALS & METHODS: A MICROARRAY DISCOVERY-BASED STUDY WAS INITIATED TO DETERMINE DNA METHYLATION IN CLL CASES WITH A RANGE OF CD38 EXPRESSION (1-92%). RESULTS: MANY LOCI WERE EITHER METHYLATED OR UNMETHYLATED ACROSS ALL CD38 LEVELS, BUT DIFFERENTIAL METHYLATION WAS ALSO OBSERVED FOR SOME GENES. GENOMIC SEQUENCING OF DLEU7 CONFIRMED EXTENSIVE CYTOSINE METHYLATION PREFERENTIALLY IN PATIENT SAMPLES WITH LOW CD38 EXPRESSION, WHEREAS NRP2, SFRP2 AND ADAM12 WERE MORE COMMONLY METHYLATED IN THOSE WITH HIGH CD38 EXPRESSION. CONCLUSION: THIS STUDY DEMONSTRATES THAT CLL IS AFFECTED BY CPG ISLAND METHYLATION IN SOME GENES THAT SEGREGATE WITH CD38 EXPRESSION LEVELS, WHILE MOST OTHERS SHOW SIMILAR METHYLATION PATTERNS ACROSS ALL LEVELS. THE CPG ISLAND METHYLATION IN CERTAIN FUNCTIONAL GENE GROUPS AND PATHWAY-ASSOCIATED GENES THAT ARE KNOWN TO BE DEREGULATED IN CLL PROVIDES ADDITIONAL INSIGHTS INTO THE CLL METHYLOME AND EPIGENETIC CONTRIBUTION TO CELLULAR DYSFUNCTION. IT WILL NOW BE USEFUL TO INVESTIGATE THE EFFECTIVENESS OF EPIGENETIC THERAPEUTIC REVERSAL OF THESE ALTERATIONS TO DEVELOP EFFECTIVE TREATMENTS FOR THE DISEASE.	2009	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
8 6613 37 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
9 2753 29 EXPRESSION OF BCL2L12 IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS: ASSOCIATION WITH CLINICAL AND MOLECULAR PROGNOSTIC MARKERS. DYSREGULATION OF APOPTOSIS IS A DISTINCTIVE FEATURE OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), ALTHOUGH A UNIQUE MECHANISM UNDERLYING APOPTOSIS RESISTANCE OF CLL B LYMPHOCYTES HAS NOT BEEN IDENTIFIED YET. ABERRANT EXPRESSION AS WELL AS GENETIC AND EPIGENETIC ALTERATIONS OF NUMEROUS GENES INVOLVED IN DIFFERENT PATHWAYS OF APOPTOSIS REGULATION HAS BEEN DESCRIBED IN CLL. HERE, WE REPORT THE EXPRESSION ANALYSIS OF BCL2L12 (BCL2-LIKE 12), A NOVEL APOPTOTIC GENE BELONGING TO BCL2 FAMILY, IN 58 SERBIAN CLL PATIENTS. QUANTITATIVE REVERSE-TRANSCRIPTASE POLYMERASE CHAIN REACTION (QRT-PCR) ANALYSIS REVEALED A SIGNIFICANT OVEREXPRESSION OF BCL2L12 MRNA IN CLL SAMPLES COMPARED TO NON-LEUKEMIC SAMPLES, IMPLYING ITS ROLE IN THE PATHOGENESIS OF THE DISEASE. RECEIVER OPERATING CHARACTERISTIC (ROC) ANALYSIS SHOWED THAT BCL2L12 EXPRESSION EFFICIENTLY DISCRIMINATES CLL CASES FROM HEALTHY CONTROLS. HOWEVER, RELATIVELY HOMOGENOUS BCL2L12 MRNA EXPRESSION AMONG PATIENTS DID NOT REFLECT THEIR CLINICAL CHARACTERISTICS (WITH THE EXCEPTION OF LACTATE DEHYDROGENASE STATUS AND TIME FROM DIAGNOSIS TO TREATMENT) AND FAILED TO SHOW ASSOCIATION WITH THE MOST INFORMATIVE PROGNOSTIC MARKERS, NAMELY THE MUTATIONAL STATUS OF REARRANGED IMMUNOGLOBULIN HEAVY CHAIN VARIABLE REGION GENES, CD38 AND LIPOPROTEIN LIPASE GENE (LPL) EXPRESSION.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
10   15 33 450K-ARRAY ANALYSIS OF CHRONIC LYMPHOCYTIC LEUKEMIA CELLS REVEALS GLOBAL DNA METHYLATION TO BE RELATIVELY STABLE OVER TIME AND SIMILAR IN RESTING AND PROLIFERATIVE COMPARTMENTS. IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), THE MICROENVIRONMENT INFLUENCES GENE EXPRESSION PATTERNS; HOWEVER, KNOWLEDGE IS LIMITED REGARDING THE EXTENT TO WHICH METHYLATION CHANGES WITH TIME AND EXPOSURE TO SPECIFIC MICROENVIRONMENTS. USING HIGH-RESOLUTION 450K ARRAYS, WE PROVIDE THE MOST COMPREHENSIVE DNA METHYLATION STUDY OF CLL TO DATE, ANALYZING PAIRED DIAGNOSTIC/FOLLOW-UP SAMPLES FROM IGHV-MUTATED/UNTREATED AND IGHV-UNMUTATED/TREATED PATIENTS (N=36) AND PATIENT-MATCHED PERIPHERAL BLOOD AND LYMPH NODE SAMPLES (N=20). ON AN UNPRECEDENTED SCALE, WE REVEALED 2239 DIFFERENTIALLY METHYLATED CPG SITES BETWEEN IGHV-MUTATED AND UNMUTATED PATIENTS, WITH THE MAJORITY OF SITES POSITIONED OUTSIDE ANNOTATED CPG ISLANDS. INTRIGUINGLY, CLL PROGNOSTIC GENES (FOR EXAMPLE, CLLU1, LPL, ZAP70 AND NOTCH1), EPIGENETIC REGULATOR (FOR EXAMPLE, HDAC9, HDAC4 AND DNMT3B), B-CELL SIGNALING (FOR EXAMPLE, IBTK) AND NUMEROUS TGF-BETA AND NF-KAPPAB/TNF PATHWAY GENES WERE ALTERNATIVELY METHYLATED BETWEEN SUBGROUPS. CONTRARY, DNA METHYLATION OVER TIME WAS DEEMED RATHER STABLE WITH FEW RECURRENT CHANGES NOTED WITHIN SUBGROUPS. ALTHOUGH A LARGER NUMBER OF NON-RECURRENT CHANGES WERE IDENTIFIED AMONG IGHV-UNMUTATED RELATIVE TO MUTATED CASES OVER TIME, THESE EQUATED TO A LOW GLOBAL CHANGE. SIMILARLY, FEW CHANGES WERE IDENTIFIED BETWEEN COMPARTMENT CASES. ALTOGETHER, WE REVEAL CLL SUBGROUPS TO DISPLAY UNIQUE METHYLATION PROFILES AND UNVEIL METHYLATION AS RELATIVELY STABLE OVER TIME AND SIMILAR WITHIN DIFFERENT CLL COMPARTMENTS, IMPLYING ABERRANT METHYLATION AS AN EARLY LEUKEMOGENIC EVENT.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
11 1473 33 DISTINCT PATTERNS OF GLOBAL PROMOTER METHYLATION IN EARLY STAGE CHRONIC LYMPHOCYTIC LEUKEMIA. GENOMIC AND EPIGENOMIC STUDIES OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) ARE RESHAPING OUR UNDERSTANDING OF THE DISEASE AND HAVE PROVIDED NEW PERSPECTIVES FOR A MORE INDIVIDUALIZED DIAGNOSIS AND NEW POTENTIAL THERAPEUTIC TARGETS. IN THIS STUDY, THE GLOBAL PROMOTER METHYLATION PROFILE WAS DETERMINED IN HIGHLY PURIFIED B-CELLS FROM 37 (BINET STAGE A) CLL PATIENTS, USING HIGH-RESOLUTION METHYLATION MICROARRAYS (27,578 CPG). OVERALL, THE METHYLATION PATTERN CORRELATED WITH THE MAJOR BIOLOGICAL (ZAP-70 AND CD38), AND MOLECULAR (IGHV MUTATION) MARKERS, DISTINGUISHING CLL CASES ACCORDING TO IGHV MUTATIONAL STATUS. CELL ADHESION MOLECULES WERE ENRICHED IN THE SIGNATURE OF UNMUTATED (UM) VERSUS MUTATED (M-) CLL. MOREOVER, IN M-CLL CPG HYPER-METHYLATION IN THREE GENES, INCLUDING SPG20, WAS SIGNIFICANTLY ANTI-CORRELATED WITH THE CORRESPONDING GENE EXPRESSION LEVEL. FINALLY, THE CORRELATION BETWEEN THE METHYLATION PATTERN AND CLINICAL PARAMETERS WAS INVESTIGATED. NOTABLY, OUT OF 42 METHYL-PROBES THAT WERE SIGNIFICANTLY ASSOCIATED WITH PROGRESSION FREE SURVIVAL (PFS), HYPER-METHYLATION OF SPG20 WAS ALSO POSITIVELY ASSOCIATED WITH PFS. THESE DATA SUPPORT THE NOTION THAT EPIGENETIC CHANGES HAVE CLINICAL IMPACT IN CLL AND MAY CONTRIBUTE TO THE IDENTIFICATION OF NOVEL CANDIDATE DISEASE-ASSOCIATED GENES POTENTIALLY USEFUL TO PREDICT THE CLINICAL OUTCOME OF EARLY STAGE CLL PATIENTS.	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
12 3740 29 INSIGHT INTO GENETIC PREDISPOSITION TO CHRONIC LYMPHOCYTIC LEUKEMIA FROM INTEGRATIVE EPIGENOMICS. GENOME-WIDE ASSOCIATION STUDIES HAVE PROVIDED EVIDENCE FOR INHERITED GENETIC PREDISPOSITION TO CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). TO GAIN INSIGHT INTO THE MECHANISMS UNDERLYING CLL RISK WE ANALYZE CHROMATIN ACCESSIBILITY, ACTIVE REGULATORY ELEMENTS MARKED BY H3K27AC, AND DNA METHYLATION AT 42 RISK LOCI IN UP TO 486 PRIMARY CLLS. WE IDENTIFY THAT RISK LOCI ARE SIGNIFICANTLY ENRICHED FOR ACTIVE CHROMATIN IN CLL WITH EVIDENCE OF BEING CLL-SPECIFIC OR DIFFERENTIALLY REGULATED IN NORMAL B-CELL DEVELOPMENT. WE THEN USE IN SITU PROMOTER CAPTURE HI-C, IN CONJUNCTION WITH GENE EXPRESSION DATA TO REVEAL LIKELY TARGET GENES OF THE RISK LOCI. CANDIDATE TARGET GENES ARE ENRICHED FOR PATHWAYS RELATED TO B-CELL DEVELOPMENT SUCH AS MYC AND BCL2 SIGNALLING. AT 14 LOCI THE ANALYSIS HIGHLIGHTS 63 VARIANTS AS THE PROBABLE FUNCTIONAL BASIS OF CLL RISK. BY INTEGRATING GENETIC AND EPIGENETIC INFORMATION OUR ANALYSIS REVEALS NOVEL INSIGHTS INTO THE RELATIONSHIP BETWEEN INHERITED PREDISPOSITION AND THE REGULATORY CHROMATIN LANDSCAPE OF CLL.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
13 3098 26 GENOMIC DISRUPTION OF THE HISTONE METHYLTRANSFERASE SETD2 IN CHRONIC LYMPHOCYTIC LEUKAEMIA. HISTONE METHYLTRANSFERASES (HMTS) ARE IMPORTANT EPIGENETIC REGULATORS OF GENE TRANSCRIPTION AND ARE DISRUPTED AT THE GENOMIC LEVEL IN A SPECTRUM OF HUMAN TUMOURS INCLUDING HAEMATOLOGICAL MALIGNANCIES. USING HIGH-RESOLUTION SINGLE NUCLEOTIDE POLYMORPHISM (SNP) ARRAYS, WE IDENTIFIED RECURRENT DELETIONS OF THE SETD2 LOCUS IN 3% (8/261) OF CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL) PATIENTS. FURTHER VALIDATION IN TWO INDEPENDENT COHORTS SHOWED THAT SETD2 DELETIONS WERE ASSOCIATED WITH LOSS OF TP53, GENOMIC COMPLEXITY AND CHROMOTHRIPSIS. WITH NEXT-GENERATION SEQUENCING WE DETECTED MUTATIONS OF SETD2 IN AN ADDITIONAL 3.8% OF PATIENTS (23/602). IN MOST CASES, SETD2 DELETIONS OR MUTATIONS WERE OFTEN OBSERVED AS A CLONAL EVENT AND ALWAYS AS A MONO-ALLELIC LESION, LEADING TO REDUCED MRNA EXPRESSION IN SETD2-DISRUPTED CASES. PATIENTS WITH SETD2 ABNORMALITIES AND WILD-TYPE TP53 AND ATM FROM FIVE CLINICAL TRIALS EMPLOYING CHEMOTHERAPY OR CHEMO-IMMUNOTHERAPY HAD REDUCED PROGRESSION-FREE AND OVERALL SURVIVAL COMPARED WITH CASES WILD TYPE FOR ALL THREE GENES. CONSISTENT WITH ITS POSTULATED ROLE AS A TUMOUR SUPPRESSOR, OUR DATA HIGHLIGHT SETD2 ABERRATION AS A RECURRENT, EARLY LOSS-OF-FUNCTION EVENT IN CLL PATHOBIOLOGY LINKED TO AGGRESSIVE DISEASE.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
14 6684 27 VALIDATION OF AN LC-MS BASED APPROACH FOR PROFILING HISTONES IN CHRONIC LYMPHOCYTIC LEUKEMIA. THE IN VITRO EVALUATION OF HISTONES AND THEIR PTMS HAS DRAWN SUBSTANTIAL INTEREST IN THE DEVELOPMENT OF EPIGENETIC THERAPIES. THE DIFFERENTIAL EXPRESSION OF HISTONE ISOFORMS MAY SERVE AS A POTENTIAL MARKER IN THE CLASSIFICATION OF DISEASES AFFECTED BY CHROMATIN ABNORMALITIES. IN THIS STUDY, PROTEIN PROFILING BY LC AND MS WAS USED TO EXPLORE DIFFERENCES IN HISTONE COMPOSITION IN PRIMARY CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) CELLS. EXTENSIVE METHOD VALIDATIONS WERE PERFORMED TO DETERMINE THE EXPERIMENTAL VARIANCES THAT WOULD IMPACT HISTONE RELATIVE ABUNDANCE. THE RESULTING DATA DEMONSTRATED THAT THE PROPOSED METHODOLOGY WAS SUITABLE FOR THE ANALYSIS OF HISTONE PROFILES. IN 4 NORMAL INDIVIDUALS AND 40 CLL PATIENTS, A SIGNIFICANT DECREASE IN THE RELATIVE ABUNDANCE OF HISTONE H2A VARIANTS (H2AFL AND H2AFA/M*) WAS OBSERVED IN PRIMARY CLL CELLS AS COMPARED TO NORMAL B CELLS. PROTEIN IDENTITIES WERE DETERMINED USING HIGH MASS ACCURACY MS AND SHOTGUN PROTEOMICS.	2009	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
15 3455 31 HYPOMETHYLATION COORDINATES ANTAGONISTICALLY WITH HYPERMETHYLATION IN CANCER DEVELOPMENT: A CASE STUDY OF LEUKEMIA. BACKGROUND: METHYLATION CHANGES ARE FREQUENT IN CANCERS, BUT UNDERSTANDING HOW HYPER- AND HYPOMETHYLATED REGION CHANGES COORDINATE, ASSOCIATE WITH GENOMIC FEATURES, AND AFFECT GENE EXPRESSION IS NEEDED TO BETTER UNDERSTAND THEIR BIOLOGICAL SIGNIFICANCE. THE FUNCTIONAL SIGNIFICANCE OF HYPERMETHYLATION IS WELL STUDIED, BUT THAT OF HYPOMETHYLATION REMAINS LIMITED. HERE, WITH PAIRED EXPRESSION AND METHYLATION SAMPLES GATHERED FROM A PATIENT/CONTROL COHORT, WE ATTEMPT TO BETTER CHARACTERIZE THE GENE EXPRESSION AND METHYLATION CHANGES THAT TAKE PLACE IN CANCER FROM B CELL CHRONIC LYMPHOCYTE LEUKEMIA (B-CLL) SAMPLES. RESULTS: ACROSS THE DATASET, WE FOUND THAT CONSISTENT DIFFERENTIALLY HYPOMETHYLATED REGIONS (C-DMRS) ACROSS SAMPLES WERE RELATIVELY FEW COMPARED TO THE MANY POORLY CONSISTENT HYPO- AND HIGHLY CONSERVED HYPER-DMRS. HOWEVER, GENES IN THE HYPO-C-DMRS TENDED TO BE ASSOCIATED WITH FUNCTIONS ANTAGONISTIC TO THOSE IN THE HYPER-C-DMRS, LIKE DIFFERENTIATION, CELL-CYCLE REGULATION AND PROLIFERATION, SUGGESTING COORDINATED REGULATION OF METHYLATION CHANGES. HYPO-C-DMRS IN B-CLL WERE FOUND ENRICHED IN KEY SIGNALING PATHWAYS LIKE B CELL RECEPTOR AND P53 PATHWAYS AND GENES/MOTIFS ESSENTIAL FOR B LYMPHOPOIESIS. HYPO-C-DMRS TENDED TO BE PROXIMAL TO GENES WITH ELEVATED EXPRESSION IN CONTRAST TO THE TRANSCRIPTION SILENCING-MECHANISM IMPOSED BY HYPERMETHYLATION. HYPO-C-DMRS TENDED TO BE ENRICHED IN THE REGIONS OF ACTIVATING H4K4ME1/2/3, H3K79ME2, AND H3K27AC HISTONE MODIFICATIONS. IN COMPARISON, THE POLYCOMB REPRESSIVE COMPLEX 2 (PRC2) SIGNATURE, MARKED BY EZH2, SUZ12, CTCF BINDING-SITES, REPRESSIVE H3K27ME3 MARKS, AND "REPRESSED/POISED PROMOTER" STATES WERE ASSOCIATED WITH HYPER-C-DMRS. MOST HYPO-C-DMRS WERE FOUND IN INTRONS (36 %), 3' UNTRANSLATED REGIONS (29 %), AND INTERGENIC REGIONS (24 %). MANY OF THESE GENIC REGIONS ALSO OVERLAPPED WITH ENHANCERS. THE METHYLATION OF CPGS FROM 3'UTR EXONS WAS FOUND TO HAVE WEAK BUT POSITIVE CORRELATION WITH GENE EXPRESSION. IN CONTRAST, METHYLATION IN THE 5'UTR WAS NEGATIVELY CORRELATED WITH EXPRESSION. TO BETTER CHARACTERIZE THE OVERLAP BETWEEN METHYLATION AND EXPRESSION CHANGES, WE IDENTIFIED CORRELATION MODULES THAT ASSOCIATE WITH "APOPTOSIS" AND "LEUKOCYTE ACTIVATION". CONCLUSIONS: DESPITE CLINICAL HETEROGENEITY IN DISEASE PRESENTATION, A NUMBER OF METHYLATION CHANGES, BOTH HYPO AND HYPER, APPEAR TO BE COMMON IN B-CLL. HYPOMETHYLATION APPEARS TO PLAY AN ACTIVE, TARGETED, AND COMPLEMENTARY ROLE IN CANCER PROGRESSION, AND IT INTERPLAYS WITH HYPERMETHYLATION IN A COORDINATED FASHION IN THE CANCER PROCESS.	2016	

16 5275 39 PROMOTER METHYLATION OF THE BONE MORPHOGENETIC PROTEIN-6 GENE IN ASSOCIATION WITH ADULT T-CELL LEUKEMIA. BONE MORPHOGENETIC PROTEINS (BMP), BELONGING TO THE TRANSFORMING GROWTH FACTOR-BETA SUPERFAMILY, ARE MULTIFUNCTIONAL REGULATORS OF CELL PROLIFERATION, DIFFERENTIATION AND APOPTOSIS IN VARIOUS TYPES OF MALIGNANT CELLS. IN THIS STUDY, WE INVESTIGATED BMP-6 PROMOTER METHYLATION IN PATIENTS WITH VARIOUS TYPES OF LEUKEMIAS. THE BMP-6 METHYLATION WAS FOUND PREFERENTIALLY IN ADULT T-CELL LEUKEMIA (ATL) (49 OF 60, 82%) COMPARED WITH OTHER TYPES OF LEUKEMIAS STUDIED INCLUDING ACUTE MYELOID LEUKEMIA (3 OF 67, 5%), ACUTE LYMPHOBLASTIC LEUKEMIA (6 OF 38, 16%) AND CHRONIC LYMPHOCYTIC LEUKEMIA (1 OF 21, 5%). AMONG SUBTYPES OF ATL, THE BMP-6 GENE WAS MORE FREQUENTLY METHYLATED IN AGGRESSIVE ATL FORMS OF ACUTE (96%) AND LYMPHOMA (94%) TYPES THAN LESS MALIGNANT CHRONIC ATL (44%) AND SMOLDERING ATL (20%). WE ALSO ANALYZED THE METHYLATION STATUS OF PERIPHERAL BLOOD MONONUCLEAR CELLS FROM HEALTHY DONORS AND NONMALIGNANT LYMPH NODES WITH REACTIVE LYMPHADENOPATHY, NONE OF WHICH SHOWED DETECTABLE BMP-6 METHYLATION IN THIS STUDY. THE BMP-6 METHYALTION WAS CORRELATED WITH DECREASED MRNA TRANSCRIPT AND PROTEIN EXPRESSION. EXPRESSION OF BMP-6 WAS RESTORED BY THE DEMETHYLATING AGENT 5-AZA-2'-DEOXYCYTIDINE, SUGGESTING THAT METHYLATION WAS ASSOCIATED WITH THE TRANSCRIPTIONAL SILENCING. SERIAL ANALYSIS DEMONSTRATED AN INCREASING METHYLATION OF CPG SITES IN THE BMP-6 PROMOTER AND THE RESULTANT SUPPRESSION OF BMP-6 EXPRESSION AS ATL PROGRESSED. THESE FINDINGS SUGGESTED THAT BMP-6 PROMOTER METHYLATION IS LIKELY TO BE A COMMON EPIGENETIC EVENT AT LATER STAGES OF ATL AND THAT THE METHYLATION PROFILES MAY BE USEFUL FOR THE STAGING OF ATL AS WELL AS FOR EVALUATION OF THE INDIVIDUAL RISK OF DEVELOPING THE DISEASE.	2008	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
17   27 30 A B-CELL EPIGENETIC SIGNATURE DEFINES THREE BIOLOGIC SUBGROUPS OF CHRONIC LYMPHOCYTIC LEUKEMIA WITH CLINICAL IMPACT. PROSPECTIVE IDENTIFICATION OF PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) DESTINED TO PROGRESS WOULD GREATLY FACILITATE THEIR CLINICAL MANAGEMENT. RECENTLY, WHOLE-GENOME DNA METHYLATION ANALYSES IDENTIFIED THREE CLINICOBIOLOGIC CLL SUBGROUPS WITH AN EPIGENETIC SIGNATURE RELATED TO DIFFERENT NORMAL B-CELL COUNTERPARTS. HERE, WE DEVELOPED A CLINICALLY APPLICABLE METHOD TO IDENTIFY THESE SUBGROUPS AND TO STUDY THEIR CLINICAL RELEVANCE. USING A SUPPORT VECTOR MACHINE APPROACH, WE BUILT A PREDICTION MODEL USING FIVE EPIGENETIC BIOMARKERS THAT WAS ABLE TO CLASSIFY CLL PATIENTS ACCURATELY INTO THE THREE SUBGROUPS, NAMELY NAIVE B-CELL-LIKE, INTERMEDIATE AND MEMORY B-CELL-LIKE CLL. DNA METHYLATION WAS QUANTIFIED BY HIGHLY REPRODUCIBLE BISULFITE PYROSEQUENCING ASSAYS IN TWO INDEPENDENT CLL SERIES. IN THE INITIAL SERIES (N=211), THE THREE SUBGROUPS SHOWED DIFFERENTIAL LEVELS OF IGHV (IMMUNOGLOBULIN HEAVY-CHAIN LOCUS) MUTATION (P<0.001) AND VH USAGE (P<0.03), AS WELL AS DIFFERENT CLINICAL FEATURES AND OUTCOME IN TERMS OF TIME TO FIRST TREATMENT (TTT) AND OVERALL SURVIVAL (P<0.001). A MULTIVARIATE COX MODEL SHOWED THAT EPIGENETIC CLASSIFICATION WAS THE STRONGEST PREDICTOR OF TTT (P<0.001) ALONG WITH BINET STAGE (P<0.001). THESE FINDINGS WERE CORROBORATED IN A VALIDATION SERIES (N=97). IN THIS STUDY, WE DEVELOPED A SIMPLE AND ROBUST METHOD USING EPIGENETIC BIOMARKERS TO CATEGORIZE CLLS INTO THREE SUBGROUPS WITH DIFFERENT CLINICOBIOLOGIC FEATURES AND OUTCOME.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
18 2025 27 EPIGENETIC CHANGES DURING DISEASE PROGRESSION IN A MURINE MODEL OF HUMAN CHRONIC LYMPHOCYTIC LEUKEMIA. EPIGENETIC ALTERATIONS, INCLUDING GAIN OR LOSS OF DNA METHYLATION, ARE A HALLMARK OF NEARLY EVERY MALIGNANCY. CHANGES IN DNA METHYLATION CAN IMPACT EXPRESSION OF CANCER-RELATED GENES INCLUDING APOPTOSIS REGULATORS AND TUMOR SUPPRESSORS. BECAUSE SUCH EPIGENETIC CHANGES ARE REVERSIBLE, THEY ARE BEING AGGRESSIVELY INVESTIGATED AS POTENTIAL THERAPEUTIC TARGETS. HERE WE USE THE EMU-TCL1 TRANSGENIC MOUSE MODEL OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) TO DETERMINE THE TIMING AND PATTERNS OF ABERRANT DNA METHYLATION, AND TO INVESTIGATE THE MECHANISMS THAT LEAD TO ABERRANT DNA METHYLATION. WE SHOW THAT CLL CELLS FROM EMU-TCL1 MICE AT VARIOUS STAGES RECAPITULATE EPIGENETIC ALTERATIONS SEEN IN HUMAN CLL. ABERRANT METHYLATION OF PROMOTER SEQUENCES IS OBSERVED AS EARLY AS 3 MONTHS OF AGE IN THESE ANIMALS, WELL BEFORE DISEASE ONSET. ABNORMALLY METHYLATED PROMOTER REGIONS INCLUDE BINDING SITES FOR THE TRANSCRIPTION FACTOR FOXD3. WE SHOW THAT LOSS OF FOXD3 EXPRESSION DUE TO AN NF-KAPPAB P50/P50:HDAC1 REPRESSOR COMPLEX OCCURS IN TCL1-POSITIVE B CELLS BEFORE METHYLATION. THEREFORE, SPECIFIC TRANSCRIPTIONAL REPRESSION IS AN EARLY EVENT LEADING TO EPIGENETIC SILENCING OF TARGET GENES IN MURINE AND HUMAN CLL. THESE RESULTS PROVIDE STRONG RATIONALE FOR THE DEVELOPMENT OF STRATEGIES TO TARGET NF-KAPPAB COMPONENTS IN CLL AND POTENTIALLY OTHER B-CELL MALIGNANCIES.	2009	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
19 4694 30 NEXT-GENERATION SEQUENCING IDENTIFIES MAJOR DNA METHYLATION CHANGES DURING PROGRESSION OF PH+ CHRONIC MYELOID LEUKEMIA. LITTLE IS KNOWN ABOUT THE IMPACT OF DNA METHYLATION ON THE EVOLUTION/PROGRESSION OF PH+ CHRONIC MYELOID LEUKEMIA (CML). WE INVESTIGATED THE METHYLOME OF CML PATIENTS IN CHRONIC PHASE (CP-CML), ACCELERATED PHASE (AP-CML) AND BLAST CRISIS (BC-CML) AS WELL AS IN CONTROLS BY REDUCED REPRESENTATION BISULFITE SEQUENCING. ALTHOUGH ONLY ~600 DIFFERENTIALLY METHYLATED CPG SITES WERE IDENTIFIED IN SAMPLES OBTAINED FROM CP-CML PATIENTS COMPARED WITH CONTROLS, ~6500 DIFFERENTIALLY METHYLATED CPG SITES WERE FOUND IN SAMPLES FROM BC-CML PATIENTS. IN THE MAJORITY OF AFFECTED CPG SITES, METHYLATION WAS INCREASED. IN CP-CML PATIENTS WHO PROGRESSED TO AP-CML/BC-CML, WE IDENTIFIED UP TO 897 GENES THAT WERE METHYLATED AT THE TIME OF PROGRESSION BUT NOT AT THE TIME OF DIAGNOSIS. USING RNA-SEQUENCING, WE OBSERVED DOWNREGULATED EXPRESSION OF MANY OF THESE GENES IN BC-CML COMPARED WITH CP-CML SAMPLES. SEVERAL OF THEM ARE WELL-KNOWN TUMOR-SUPPRESSOR GENES OR REGULATORS OF CELL PROLIFERATION, AND GENE RE-EXPRESSION WAS OBSERVED BY THE USE OF EPIGENETIC ACTIVE DRUGS. TOGETHER, OUR RESULTS DEMONSTRATE THAT CPG SITE METHYLATION CLEARLY INCREASES DURING CML PROGRESSION AND THAT IT MAY PROVIDE A USEFUL BASIS FOR REVEALING NEW TARGETS OF THERAPY IN ADVANCED CML.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
20 2639 31 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