1 5848 127 SUBCLONES IN B-LYMPHOMA CELL LINES: ISOGENIC MODELS FOR THE STUDY OF GENE REGULATION. GENETIC HETEROGENEITY THOUGH COMMON IN TUMORS HAS BEEN RARELY DOCUMENTED IN CELL LINES. TO EXAMINE HOW OFTEN B-LYMPHOMA CELL LINES ARE COMPRISED OF SUBCLONES, WE PERFORMED IMMUNOGLOBULIN (IG) HEAVY CHAIN HYPERMUTATION ANALYSIS. REVEALING THAT SUBCLONES ARE NOT RARE IN B-CELL LYMPHOMA CELL LINES, 6/49 IG HYPERMUTATED CELL LINES (12%) CONSISTED OF SUBCLONES WITH INDIVIDUAL IG MUTATIONS. SUBCLONES WERE ALSO IDENTIFIED IN 2/284 LEUKEMIA/LYMPHOMA CELL LINES EXHIBITING BIMODAL CD MARKER EXPRESSION. WE SUCCESSFULLY ISOLATED 10 SUBCLONES FROM FOUR CELL LINES (HG3, SU-DHL-5, TMD-8, U-2932). WHOLE EXOME SEQUENCING WAS PERFORMED TO MOLECULARLY CHARACTERIZE THESE SUBCLONES. WE DESCRIBE IN DETAIL THE CLONAL STRUCTURE OF CELL LINE HG3, DERIVED FROM CHRONIC LYMPHOCYTIC LEUKEMIA. HG3 CONSISTS OF THREE SUBCLONES EACH BEARING CLONE-SPECIFIC ABERRATIONS, GENE EXPRESSION AND DNA METHYLATION PATTERNS. WHILE DONOR PATIENT LEUKEMIC CELLS WERE CD5+, TWO OF THREE HG3 SUBCLONES HAD INDEPENDENTLY LOST THIS MARKER. CD5 ON HG3 CELLS WAS REGULATED BY EPIGENETIC/TRANSCRIPTIONAL MECHANISMS RATHER THAN BY ALTERNATIVE SPLICING AS REPORTED HITHERTO. IN CONCLUSION, WE SHOW THAT THE PRESENCE OF SUBCLONES IN CELL LINES CARRYING INDIVIDUAL MUTATIONS AND CHARACTERIZED BY SETS OF DIFFERENTIALLY EXPRESSED GENES IS NOT UNCOMMON. WE SHOW ALSO THAT THESE SUBCLONES CAN BE USEFUL ISOGENIC MODELS FOR REGULATORY AND FUNCTIONAL STUDIES.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
2 4221  36 METHYLATION AND SILENCING OF PROTEIN TYROSINE PHOSPHATASE RECEPTOR TYPE O IN CHRONIC LYMPHOCYTIC LEUKEMIA. PURPOSE: PREVIOUS STUDIES IN OUR LABORATORY HAVE SHOWN THE PROGRESSIVE METHYLATION AND SUPPRESSION OF THE GENE ENCODING PROTEIN TYROSINE PHOSPHATASE, PTPRO, IN THE LIVERS OF RATS FED A METHYL-DEFICIENT DIET THAT INDUCES HEPATOCARCINOGENESIS. SUBSEQUENTLY, WE OBSERVED THE METHYLATION OF PTPRO IN PRIMARY HUMAN LUNG TUMORS AND ALSO SHOWED ITS POTENTIAL TUMOR SUPPRESSOR CHARACTERISTICS. THE PRESENT STUDY WAS UNDERTAKEN TO INVESTIGATE WHETHER THE TRUNCATED FORM OF PTPRO (PTPROT), SPECIFICALLY EXPRESSED IN NAIVE B LYMPHOCYTES, WAS ALSO METHYLATED AND SUPPRESSED IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), A DISEASE GENERALLY AFFECTING B LYMPHOCYTES. EXPERIMENTAL DESIGN AND RESULTS: INITIAL SCREENING SHOWED THAT 60% OF THE 52 CLL SAMPLES ANALYZED USING METHYLATION-SPECIFIC PCR ASSAY WERE METHYLATED COMPARED WITH B LYMPHOCYTES FROM NORMAL INDIVIDUALS, WHICH WERE NOT METHYLATED. THE EXPRESSION OF PTPROT, AS MEASURED BY SEMIQUANTITATIVE REVERSE TRANSCRIPTION-PCR, INVERSELY CORRELATED WITH METHYLATION IN THE FEW SAMPLES TESTED. ANALYSIS OF ADDITIONAL SAMPLES (N = 50) BY COMBINED BISULFITE RESTRICTION ANALYSIS SHOWED THAT THE PTPRO CPG ISLAND WAS METHYLATED IN 82% OF PATIENTS WITH CLL COMPARED WITH B LYMPHOCYTES FROM NORMAL INDIVIDUALS. FURTHERMORE, OVERALL EXPRESSION OF PTPRO WAS REDUCED IN CLL RELATIVE TO NORMAL LYMPHOCYTES. THE PTPRO GENE WAS ALSO SUPPRESSED BY METHYLATION IN THE CLL CELL LINE WAC3CD5, WHERE IT COULD BE REACTIVATED UPON TREATMENT WITH THE DNA HYPOMETHYLATING AGENT 5-AZAC. ECTOPIC EXPRESSION OF PTPROT IN A NONEXPRESSING CELL LINE INCREASED GROWTH INHIBITION WITH FLUDARABINE TREATMENT, A THERAPY COMMONLY USED FOR CLL. CONCLUSION: THIS STUDY REVEALS THE POTENTIAL ROLE OF PTPRO METHYLATION AND SILENCING IN CLL TUMORIGENESIS AND ALSO PROVIDES A NOVEL MOLECULAR TARGET IN THE EPIGENETIC THERAPY.	2007	
                                                                                                                                                                                                                                                                                             
3 3500  39 IDENTIFICATION OF NOVEL, CLONALLY STABLE, SOMATIC MUTATIONS TARGETING TRANSCRIPTION FACTORS PAX5 AND NKX2-3, THE EPIGENETIC REGULATOR LRIF1, AND BRAF IN A CASE OF ATYPICAL B-CELL CHRONIC LYMPHOCYTIC LEUKEMIA HARBORING A T(14;18)(Q32;Q21). DIAGNOSIS OF B-CELL CHRONIC LYMPHOCYTIC LEUKEMIA (B-CLL) IS USUALLY STRAIGHTFORWARD, INVOLVING CLINICAL, IMMUNOPHENOTYPIC (MATUTES SCORE), AND (IMMUNO)GENETIC ANALYSES (TO REFINE PATIENT PROGNOSIS FOR TREATMENT). CLL CASES WITH ATYPICAL PRESENTATION (E.G., MATUTES </= 3) ARE ALSO ENCOUNTERED, AND FOR THESE DISEASES, BIOLOGY AND PROGNOSTIC IMPACT ARE LESS CLEAR. HERE WE REPORT THE GENOMIC CHARACTERIZATION OF A CASE OF ATYPICAL B-CLL IN A 70-YR-OLD MALE PATIENT; B-CLL CELLS SHOWED A MATUTES SCORE OF 3, CHROMOSOMAL TRANSLOCATION T(14;18)(Q32;Q21) (BCL2/IGH), MUTATED IGHV, DELETION 17P, AND MUTATIONS IN BCL2, NOTCH1 (SUBCLONAL), AND TP53 (SUBCLONAL). QUITE STRIKINGLY, A NOVEL PAX5 MUTATION THAT WAS PREDICTED TO BE LOSS OF FUNCTION WAS ALSO SEEN. EXOME SEQUENCING IDENTIFIED, IN ADDITION, A POTENTIALLY ACTIONABLE BRAF MUTATION, TOGETHER WITH NOVEL SOMATIC MUTATIONS AFFECTING THE HOMEOBOX TRANSCRIPTION FACTOR NKX2-3, KNOWN TO CONTROL B-LYMPHOCYTE DEVELOPMENT AND HOMING, AND THE EPIGENETIC REGULATOR LRIF1, WHICH IS IMPLICATED IN CHROMATIN COMPACTION AND GENE SILENCING. NEITHER NKX2-3 NOR LRIF1 MUTATIONS, PREDICTED TO BE LOSS OF FUNCTION, HAVE PREVIOUSLY BEEN REPORTED IN B-CLL. SEQUENCING CONFIRMED THE PRESENCE OF THESE MUTATIONS TOGETHER WITH BCL2, NOTCH1, AND BRAF MUTATIONS, WITH THE T(14;18)(Q32;Q21) TRANSLOCATION, IN THE INITIAL DIAGNOSTIC SAMPLE OBTAINED 12 YR PRIOR. THIS IS SUGGESTIVE OF A ROLE FOR THESE NOVEL MUTATIONS IN B-CLL INITIATION AND STABLE CLONAL EVOLUTION, INCLUDING UPON TREATMENT WITHDRAWAL. THIS CASE EXTENDS THE SPECTRUM OF ATYPICAL B-CLL WITH T(14;18)(Q32;Q21) AND HIGHLIGHTS THE VALUE OF MORE GLOBAL PRECISION GENOMICS FOR PATIENT FOLLOW-UP AND TREATMENT IN THESE PATIENTS.	2021	
                                                                                                                                                                                                                                                                      
4  494  31 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
5 2753  37 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
6  628  36 BIOLOGICAL AND CLINICAL INSIGHT FROM ANALYSIS OF THE TUMOR B-CELL RECEPTOR STRUCTURE AND FUNCTION IN CHRONIC LYMPHOCYTIC LEUKEMIA. THE B-CELL RECEPTOR (BCR) IS ESSENTIAL TO THE BEHAVIOR OF THE MAJORITY OF NORMAL AND NEOPLASTIC MATURE B CELLS. THE IDENTIFICATION IN 1999 OF THE TWO MAJOR CLL SUBSETS EXPRESSING UNMUTATED IMMUNOGLOBULIN (IG) VARIABLE REGION GENES (U-IGHV, U-CLL) OF PRE-GERMINAL CENTER ORIGIN AND POOR PROGNOSIS, AND MUTATED IGHV (M-CLL) OF POST-GERMINAL CENTER ORIGIN AND GOOD PROGNOSIS, IGNITED INTENSIVE INVESTIGATIONS ON STRUCTURE AND FUNCTION OF THE TUMOR BCR. THESE INVESTIGATIONS HAVE PROVIDED FUNDAMENTAL INSIGHT INTO CLL BIOLOGY AND EVENTUALLY THE MECHANISTIC RATIONALE FOR THE DEVELOPMENT OF SUCCESSFUL THERAPIES TARGETING BCR SIGNALING. U-CLL AND M-CLL ARE CHARACTERIZED BY VARIABLE LOW SURFACE IGM (SIGM) EXPRESSION AND SIGNALING CAPACITY. VARIABILITY OF SIGM CAN IN PART BE EXPLAINED BY CHRONIC ENGAGEMENT WITH (AUTO)ANTIGEN AT TISSUE SITES. HOWEVER, OTHER ENVIRONMENTAL ELEMENTS, GENETIC CHANGES, AND EPIGENETIC SIGNATURES ALSO CONTRIBUTE TO THE SIGM VARIABILITY. THE VARIABLE LEVELS HAVE CONSEQUENCES ON THE BEHAVIOR OF CLL, WHICH IS IN A STATE OF ANERGY WITH AN INDOLENT CLINICAL COURSE WHEN SIGM EXPRESSION IS LOW, OR PUSHED TOWARDS PROLIFERATION AND A MORE AGGRESSIVE CLINICAL COURSE WHEN SIGM EXPRESSION IS HIGH. EFFICACY OF THERAPIES THAT TARGET BTK MAY ALSO BE AFFECTED BY THE VARIABLE SIGM LEVELS AND SIGNALING AND, IN PART, EXPLAIN THE DEVELOPMENT OF RESISTANCE.	2022	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
7 2431  34 EPIGENETIC SILENCING OF MIR-26A1 IN CHRONIC LYMPHOCYTIC LEUKEMIA AND MANTLE CELL LYMPHOMA: IMPACT ON EZH2 EXPRESSION. DOWNREGULATION OF MIR26A1 HAS BEEN REPORTED IN VARIOUS B-CELL MALIGNANCIES; HOWEVER, THE MECHANISM BEHIND ITS DEREGULATION REMAINS LARGELY UNKNOWN. WE INVESTIGATED MIR26A1 METHYLATION AND EXPRESSION LEVELS IN A WELL-CHARACTERIZED SERIES OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) AND MANTLE CELL LYMPHOMA (MCL). FROM 450K METHYLATION ARRAYS, WE FIRST OBSERVED MIR26A1 (CG26054057) AS UNIFORMLY HYPERMETHYLATED IN MCL (N = 24) (ALL >75%), WHILE CLL (N = 18) SHOWED DIFFERENTIAL METHYLATION BETWEEN PROGNOSTIC SUBGROUPS. EXTENDED ANALYSIS USING PYROSEQUENCING CONFIRMED OUR FINDINGS AND REAL-TIME QUANTITATIVE PCR VERIFIED LOW MIR26A1 EXPRESSION IN BOTH CLL (N = 70) AND MCL (N = 38) COMPARED TO NORMAL B-CELLS. NOTABLY, THE LEVEL OF MIR26A1 METHYLATION PREDICTED OUTCOME IN CLL, WITH HIGHER LEVELS SEEN IN POOR-PROGNOSTIC, IGHV-UNMUTATED CLL. SINCE EZH2 WAS RECENTLY REPORTED AS A TARGET FOR MIR26A1, WE ANALYZED THE EXPRESSION LEVELS OF BOTH MIR26A1 AND EZH2 IN PRIMARY CLL SAMPLES AND OBSERVED AN INVERSE CORRELATION. BY OVEREXPRESSION OF MIR26A1 IN CLL AND MCL CELL LINES, REDUCED EZH2 PROTEIN LEVELS WERE OBSERVED USING BOTH WESTERN BLOT AND FLOW CYTOMETRY. IN CONTRAST, METHYL-INHIBITOR TREATMENT LED TO UPREGULATED MIR26A1 EXPRESSION WITH A PARALLEL DECREASE OF EZH2 EXPRESSION. FINALLY, INCREASED LEVELS OF APOPTOSIS WERE OBSERVED IN MIR26A1-OVEREXPRESSING CELL LINES, FURTHER UNDERSCORING THE FUNCTIONAL RELEVANCE OF MIR26A1. IN SUMMARY, WE PROPOSE THAT EPIGENETIC SILENCING OF MIR26A1 IS REQUIRED FOR THE MAINTENANCE OF INCREASED LEVELS OF EZH2, WHICH IN TURN TRANSLATE INTO A WORSE OUTCOME, AS SHOWN IN CLL, HIGHLIGHTING MIR26A1 AS A TUMOR SUPPRESSOR MIRNA.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                  
8 4694  34 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
9  493  32 ASSESSMENT OF P53 AND ATM FUNCTIONALITY IN CHRONIC LYMPHOCYTIC LEUKEMIA BY MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION. THE ATM-P53 DNA-DAMAGE RESPONSE (DDR) PATHWAY HAS A CRUCIAL ROLE IN CHEMORESISTANCE IN CLL, AS INDICATED BY THE ADVERSE PROGNOSTIC IMPACT OF GENETIC ABERRATIONS OF TP53 AND ATM. IDENTIFYING AND DISTINGUISHING TP53 AND ATM FUNCTIONAL DEFECTS HAS BECOME RELEVANT AS EPIGENETIC AND POSTTRANSCRIPTIONAL DYSREGULATION OF THE ATM/P53 AXIS IS INCREASINGLY BEING RECOGNIZED AS THE UNDERLYING CAUSE OF CHEMORESISTANCE. ALSO, SPECIFIC TREATMENTS SENSITIZING TP53- OR ATM-DEFICIENT CLL CELLS ARE EMERGING. WE THEREFORE DEVELOPED A NEW ATM-P53 FUNCTIONAL ASSAY WITH THE AIM TO (I) IDENTIFY AND (II) DISTINGUISH ABNORMALITIES OF TP53 VERSUS ATM AND (III) ENABLE THE IDENTIFICATION OF ADDITIONAL DEFECTS IN THE ATM-P53 PATHWAY. REVERSED TRANSCRIPTASE MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION (RT-MLPA) WAS USED TO MEASURE ATM AND/OR P53-DEPENDENT GENES AT THE RNA LEVEL FOLLOWING DNA DAMAGE USING IRRADIATION. HERE, WE SHOWED THAT THIS ASSAY IS ABLE TO IDENTIFY AND DISTINGUISH THREE SUBGROUPS OF CLL TUMORS (I.E., TP53-DEFECTIVE, ATM-DEFECTIVE AND WT) AND IS ALSO ABLE TO DETECT ADDITIONAL SAMPLES WITH A DEFECTIVE DDR, WITHOUT MOLECULAR ABERRATIONS IN TP53 AND/OR ATM. THESE FINDINGS MAKE THE ATM-P53 RT-MLPA FUNCTIONAL ASSAY A PROMISING PROGNOSTIC TOOL FOR PREDICTING TREATMENT RESPONSES IN CLL.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
10 4549  35 MUTATION ANALYSIS OF THERAPY-RELATED MYELOID NEOPLASMS. WE ANALYZED THE GENETIC MUTATION STATUS OF 13 PATIENTS WITH THERAPY-RELATED MYELOID NEOPLASMS (T-MN). CONSISTENT WITH PREVIOUS REPORTS, T-MN CELLS PREFERENTIALLY ACQUIRED MUTATIONS IN TP53 AND EPIGENETIC MODIFYING GENES, INSTEAD OF MUTATIONS IN TYROSINE KINASE AND SPLICEOSOME GENES. FURTHERMORE, WE COMPARED THE MUTATION STATUS OF THREE T-MN CELLS WITH EACH OF THE INITIAL LYMPHOID MALIGNANT CELLS, AND IDENTIFIED COMMON MUTATIONS AMONG T-MN AND THE INITIAL MALIGNANT CELLS IN TWO PATIENTS. IN A PATIENT WHO DEVELOPED CHRONIC MYELOMONOCYTIC LEUKEMIA (CMML) AFTER FOLLICULAR LYMPHOMA (FL), TET2 MUTATION WAS IDENTIFIED IN BOTH CMML AND FL CELLS. NOTABLY, THE TET2 MUTATION WAS ALSO IDENTIFIED IN PERIPHERAL BLOOD CELLS IN THE DISEASE-FREE PERIOD WITH THE SAME ALLELIC FREQUENCY AS CMML AND FL CELLS, BUT NOT IN A GERM-LINE CONTROL, INDICATING THAT THE TET2 MUTATION OCCURRED SOMATICALLY IN THE INITIATING CLONE FOR BOTH MALIGNANT CELLS. ON THE OTHER HAND, A GERM-LINE MYB MUTATION WAS IDENTIFIED IN A PATIENT WHO DEVELOPED MYELODYSPLASTIC SYNDROMES (MDS) AFTER FL. THESE RESULTS SUGGEST THAT GERM-LINE DEPOSITION AND CLONAL HEMATOPOIESIS ARE CLOSELY ASSOCIATED WITH T-MN SUSCEPTIBILITY; HOWEVER, FURTHER ANALYSIS IS NECESSARY TO CLARIFY THE MECHANISM REQUIRED TO PROVIDE THE INITIATING CLONE WITH LINEAGE COMMITMENT AND CLONAL EXPANSION.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
11 2088  39 EPIGENETIC DYSREGULATION OF SECRETED FRIZZLED-RELATED PROTEINS IN MYELOPROLIFERATIVE NEOPLASMS COMPLEMENTS THE JAK2V617F-MUTATION. BACKGROUND: SECRETED FRIZZLED-RELATED PROTEINS (SFRPS) ARE ANTAGONISTS OF THE WNT SIGNALING PATHWAY, WHICH PLAYS A CENTRAL ROLE IN STEM CELL MAINTENANCE AND DIFFERENTIATION OF STEM CELLS AND HEMATOPOIETIC PROGENITORS. EPIGENETIC DOWNREGULATION OF SFRPS BY PROMOTER HYPERMETHYLATION HAS BEEN DESCRIBED TO BE INVOLVED IN THE PATHOGENESIS OF HEMATOPOIETIC MALIGNANCIES. THERE IS AN ASSOCIATION BETWEEN ABERRANT WNT SIGNALING AND THE ESTABLISHED CANCER STEM CELL CONCEPT. IN CONTRAST TO BCR-ABL1-POSITIVE CHRONIC MYELOID LEUKEMIA CML, BCR-ABL1-NEGATIVE MYELOPROLIFERATIVE NEOPLASMS (PH-MPN) ARE CHARACTERIZED BY THE FREQUENT OCCURRENCE OF AN AUTOACTIVATING MUTATION IN THE JAK2 TYROSINE KINASE (JAK2V617F) OR OTHER MUTATIONS IN THE JAK-STAT PATHWAY. HOWEVER, PATHOGENETIC MECHANISMS OF JAK2 MUTATED OR UNMUTATED PH-MPN REMAIN NOT COMPLETELY UNDERSTOOD. WE DETERMINED THE PROMOTER METHYLATION STATUS OF SFRP-1, -2, -4, AND -5 IN 57 MPN PATIENT SAMPLES BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (PCR) (MSP). JAK2V617F WAS ASSESSED BY ALLELE-SPECIFIC PCR. RESULTS: ABERRANT METHYLATION AMONG PRIMARY MPN SAMPLES WAS 4% FOR SFRP-1, 25% FOR SFRP-2, 2% FOR SFRP-4, AND 0% FOR SFRP-5. HYPERMETHYLATION OF SFRP-2, WHICH WAS THE MOST FREQUENTLY HYPERMETHYLATED GENE IN OUR STUDY, COULD NOT BE CORRELATED TO ANY SPECIFIC MPN SUBTYPE. HOWEVER, WE DETECTED A SIGNIFICANT CORRELATION BETWEEN SFRP-2 METHYLATION AND PRESENCE OF A JAK2V617F MUTATION (P = 0.008). NONE OF THE 10 CML SAMPLES SHOWED ANY SFRP-METHYLATION. CONCLUSIONS: OUR DATA INDICATE THAT EPIGENETIC DYSREGULATION OF THE WNT SIGNALING PATHWAY IS A COMMON EVENT IN MPN WITH ABERRANT METHYLATION OF AT LEAST ONE SFRP BEING DETECTED IN 25% OF THE PRIMARY PATIENT SAMPLES AND IN 30% IF ONLY ACCOUNTING FOR PH-MPN. A SIGNIFICANT CORRELATION BETWEEN SFRP-2 METHYLATION AND PRESENCE OF JAK2V617F IN OUR DATA SUPPORTS THE HYPOTHESIS THAT EPIGENETIC DYSREGULATION MAY BE A COMPLEMENTARY MECHANISM TO GENETIC ABERRATIONS. ABERRANT METHYLATION OF CRUCIAL STEM CELL MAINTENANCE GENES SEEMS TO CONTRIBUTE TO DISEASE PATHOGENESIS IN PH-MPN.	2012	

12 5275  37 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	
                                                                                                                                                                                                                                                                                                                                                                                                                   
13 2469  17 EPIGENETIC TRAJECTORIES OF THE PREMALIGNANT-TO-MALIGNANT TRANSITION OF CHRONIC LYMPHOCYTIC LEUKEMIA. KRETZMER AND COLLEAGUES SHOW THAT THE TRANSITION TO ALTERED METHYLOME OCCURS VERY EARLY IN CHRONIC LYMPHOCYTIC LEUKEMIA, AND ONCE ACQUIRED, IT IS A CLONAL AND EXTREMELY STABLE CHANGE. HOWEVER, THE PRECISE TIME POINT WHEN THE LEUKEMIC CLONE STARTS DEVIATING SIGNIFICANTLY FROM THE NORMAL B-CELL DIFFERENTIATION TRAJECTORY IS STILL ELUSIVE. SEE RELATED ARTICLE BY KRETZMER ET AL., P. 54.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
14 3125  28 GHSR DNA HYPERMETHYLATION IS A COMMON EPIGENETIC ALTERATION OF HIGH DIAGNOSTIC VALUE IN A BROAD SPECTRUM OF CANCERS. IDENTIFICATION OF A SINGLE MOLECULAR TRAIT THAT IS DETERMINANT OF COMMON MALIGNANCIES MAY SERVE AS A POWERFUL DIAGNOSTIC SUPPLEMENT TO CANCER TYPE-SPECIFIC MARKERS. HERE, WE REPORT A DNA METHYLATION MARK THAT IS CHARACTERISTIC OF SEVEN STUDIED MALIGNANCIES, NAMELY CANCERS OF LUNG, BREAST, PROSTATE, PANCREAS, COLORECTUM, GLIOBLASTOMA AND B CELL CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL) (N = 137). THIS MARK WAS DEFINED BY SUBSTANTIAL HYPERMETHYLATION AT THE PROMOTER AND FIRST EXON OF GROWTH HORMONE SECRETAGOUGE RECEPTOR (GHSR) THROUGH BISULFITE PYROSEQUENCING. THE DEGREE OF ABERRANT METHYLATION WAS CAPABLE OF ACCURATE DISCRIMINATION BETWEEN CANCER AND CONTROL SAMPLES. THE HIGHEST SENSITIVITY AND SPECIFICITY OF CANCER DETECTION WAS ACHIEVED FOR CANCERS OF PANCREAS, LUNG, BREAST AND CLL YIELDING THE AREA UNDER THE CURVE (AUC) VALUES OF 1.0000, 0.9952, 0.9800 AND 0.9400, RESPECTIVELY. NARROWING TO A SINGLE CPG SITE WITHIN THE GENE'S PROMOTER OR FOUR CONSECUTIVE CPG UNITS OF THE HIGHEST METHYLATION LEVELS WITHIN THE FIRST EXON IMPROVED THE DETECTION POWER. GHSR HYPERMETHYLATION WAS DETECTED ALREADY AT THE EARLY STAGE TUMORS. THE ACCURATE PERFORMANCE OF THIS MARKER WAS FURTHER REPLICATED IN AN INDEPENDENT SET OF PANCREATIC CANCER AND CONTROL SAMPLES (N = 78). THESE FINDINGS SUPPORT THE CANDIDATURE OF GHSR METHYLATION AS A HIGHLY ACCURATE PAN-CANCER MARKER.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
15 2763  33 EXPRESSION OF THE LEUKEMIC PROGNOSTIC MARKER CD7 IS LINKED TO EPIGENETIC MODIFICATIONS IN CHRONIC MYELOID LEUKEMIA. BACKGROUND: EXPRESSION LEVELS OF THE CELL SURFACE GLYCOPROTEIN, CD7, AND THE SERINE PROTEASE, ELASTASE 2 (ELA2), IN THE LEUKEMIC CELLS OF PATIENTS WITH CHRONIC MYELOID LEUKEMIA (CML) HAVE BEEN ASSOCIATED WITH CLINICAL OUTCOME. HOWEVER, LITTLE IS KNOWN ABOUT THE MECHANISMS THAT UNDERLIE THE VARIABLE EXPRESSION OF THESE GENES IN THE LEUKEMIC CELLS. RESULTS: TO ADDRESS THIS QUESTION, WE COMPARED THE LEVEL OF THEIR EXPRESSION WITH THE DNA METHYLATION AND HISTONE ACETYLATION STATUS OF 5' SEQUENCES OF BOTH GENES IN LEUKEMIC CELL LINES AND PRIMITIVE (LIN-CD34+) LEUKEMIC CELLS FROM CHRONIC PHASE CML PATIENTS. DNA METHYLATION OF THE ELA2 GENE PROMOTER DID NOT CORRELATE WITH ITS EXPRESSION PATTERN IN LIN-CD34+ CELLS FROM CHRONIC PHASE CML PATIENT SAMPLES EVEN THOUGH THERE WAS CLEAR DIFFERENTIAL DNA METHYLATION OF THIS LOCUS IN ELA2-EXPRESSING AND NON-EXPRESSING CELL LINES. IN CONTRAST, WE FOUND A STRONG RELATION BETWEEN CD7 EXPRESSION AND TRANSCRIPTION-PERMISSIVE CHROMATIN MODIFICATIONS, BOTH AT THE LEVEL OF DNA METHYLATION AND HISTONE ACETYLATION WITH EVIDENCE OF HYPOMETHYLATION OF THE CD7 PROMOTER REGION IN THE LIN-CD34+ CELLS FROM CML PATIENTS WITH HIGH CD7 EXPRESSION. CONCLUSION: THESE FINDINGS INDICATE A LINK BETWEEN EPIGENETIC MODIFICATIONS AND CD7 EXPRESSION IN PRIMITIVE CML CELLS.	2010	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
16 1334  30 DEREGULATION OF AIOLOS EXPRESSION IN CHRONIC LYMPHOCYTIC LEUKEMIA IS ASSOCIATED WITH EPIGENETIC MODIFICATIONS. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY A CLONAL ACCUMULATION OF MATURE NEOPLASTIC B CELLS THAT ARE RESISTANT TO APOPTOSIS. AIOLOS, A MEMBER OF THE IKAROS FAMILY OF ZINC-FINGER TRANSCRIPTION FACTORS, PLAYS AN IMPORTANT ROLE IN THE CONTROL OF MATURE B LYMPHOCYTE DIFFERENTIATION AND MATURATION. IN THIS STUDY, WE SHOWED THAT AIOLOS EXPRESSION IS UP-REGULATED IN B-CLL CELLS. THIS OVEREXPRESSION DOES NOT IMPLICATE ISOFORM IMBALANCE OR DISTURB AIOLOS SUBCELLULAR LOCALIZATION. THE CHROMATIN STATUS AT THE AIOLOS PROMOTER IN CLL IS DEFINED BY THE DEMETHYLATION OF DNA AND AN ENRICHMENT OF EUCHROMATIN ASSOCIATED HISTONE MARKERS, SUCH AS THE DIMETHYLATION OF THE LYSINE 4 ON HISTONE H3. THESE EPIGENETIC MODIFICATIONS SHOULD ALLOW ITS UPSTREAM EFFECTORS, SUCH AS NUCLEAR FACTOR-KAPPAB, CONSTITUTIVELY ACTIVATED IN CLL, TO GAIN ACCESS TO PROMOTER, RESULTING UP-REGULATION OF AIOLOS. TO DETERMINE THE CONSEQUENCES OF AIOLOS DEREGULATION IN CLL, WE ANALYZED THE EFFECTS OF AIOLOS OVEREXPRESSION OR DOWN-REGULATION ON APOPTOSIS. AIOLOS IS INVOLVED IN CELL SURVIVAL BY REGULATING THE EXPRESSION OF SOME BCL-2 FAMILY MEMBERS. OUR RESULTS STRONGLY SUGGEST THAT AIOLOS DEREGULATION BY EPIGENETIC MODIFICATIONS MAY BE A HALLMARK OF CLL.	2011	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
17 5871  39 SUSTAINED NF-KAPPAB ACTIVITY IN CHRONIC LYMPHOCYTIC LEUKEMIA IS INDEPENDENT OF GENETIC AND EPIGENETIC ALTERATIONS IN THE TNFAIP3 (A20) LOCUS. INAPPROPRIATE NUCLEAR FACTOR (NF) KAPPAB ACTIVITY IS ONE MAJOR HALLMARK OF B-CELL MALIGNANCIES AND CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). NFKAPPAB-DEPENDENT GENES ARE INVOLVED IN ANTIAPOPTOSIS, CELL PROLIFERATION AND METASTASIS AND ARE RESPONSIBLE FOR SURVIVAL AND PROLIFERATION OF TUMORS. HOWEVER, THE MECHANISMS OF NFKAPPAB ACTIVITY IN CLL STILL NEED TO BE ELUCIDATED. PREVIOUSLY, WE IDENTIFIED TRANSLOCATIONS IN A REGION ON CHROMOSOME 6Q THAT ENCODES TUMOR NECROSIS FACTOR ALPHA-INDUCED PROTEIN 3, WHICH IS A KEY PLAYER IN NEGATIVE FEEDBACK LOOP REGULATION OF NFKAPPAB. INACTIVATION OF THIS UBIQUITIN-EDITING ENZYME IS INVOLVED IN IMMUNOPATHOLOGIES AND IN TUMORIGENESIS. FREQUENT MUTATIONS IN THE A20 LOCUS--LEADING TO SUSTAINED NFKAPPAB ACTIVITY--COULD BE SHOWN TO PLAY A DOMINANT ROLE IN DEVELOPMENT OF DIFFERENT B-CELL MALIGNANCIES. TO CHECK IF A20 IS INVOLVED IN UPREGULATION OF NFKAPPAB ACTIVITY IN CLL, WE SEQUENCED EXONS 2-9 OF THE A20 GENE IN 55 CLL DNA SAMPLES. FURTHERMORE, WE DETERMINED THE METHYLATION STATUS OF THE PROMOTER REGION IN 63 CLL DNA SAMPLES AND COMPARED TO 10 CONTROL DNAS OF B CELLS FROM HEALTHY DONORS. CONTRARY TO REPORTS FROM OTHER B-CELL MALIGNANCIES, THE A20 REGION SHOWED NEITHER MUTATIONS NOR ABERRANT DNA METHYLATION. MOREOVER, ITS EXPRESSION COULD BE CONFIRMED BY IMMUNOBLOTTING AND SHOWING COMPARABLE RESULTS TO HEALTHY B CELLS. THESE RESULTS INDICATE THAT MALIGNANT DEVELOPMENT IN CLL DIFFERS FROM MOST OF OTHER B-CELL MALIGNANCIES, WHICH SHOW FREQUENT INACTIVATION OF A20.	2011	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
18 1593  34 DNA METHYLATION PROFILING REVEALS A PATHOLOGICAL SIGNATURE THAT CONTRIBUTES TO TRANSCRIPTIONAL DEFECTS OF CD34(+) CD15(-) CELLS IN EARLY CHRONIC-PHASE CHRONIC MYELOID LEUKEMIA. DESPITE THE HIGH EFFICIENCY OF TYROSINE KINASE INHIBITORS (TKI), SOME PATIENTS WITH CHRONIC MYELOID LEUKEMIA (CML) WILL DISPLAY RESIDUAL DISEASE THAT CAN BECOME RESISTANT TO TREATMENT, INDICATING INTRACLONAL HETEROGENEITY IN CHRONIC-PHASE CML (CP-CML). TO DETERMINE THE BASIS OF THIS HETEROGENEITY, WE CONDUCTED THE FIRST EXHAUSTIVE CHARACTERIZATION OF THE DNA METHYLATION PATTERN OF SORTED CP-CML CD34(+) CD15(-) (IMMATURE) AND CD34(-) CD15(+) (MATURE) CELLS AT DIAGNOSIS (PRIOR TO ANY TREATMENT) AND COMPARED IT TO THAT OF CD34(+) CD15(-) AND CD34(-) CD15(+) CELLS ISOLATED FROM HEALTHY DONORS (HD). IN BOTH CELL TYPES, WE IDENTIFIED SEVERAL HUNDREDS OF DIFFERENTIALLY METHYLATED REGIONS (DMRS) SHOWING DNA METHYLATION CHANGES BETWEEN CP-CML AND HD SAMPLES, WITH ONLY A SUBSET OF THEM IN COMMON BETWEEN CD34(+) CD15(-) AND CD34(-) CD15(+) CELLS. THIS SUGGESTED DNA METHYLATION VARIABILITY WITHIN THE SAME CML CLONE. WE ALSO IDENTIFIED 70 GENES THAT COULD BE ABERRANTLY REPRESSED UPON HYPERMETHYLATION AND 171 GENES THAT COULD BE ABERRANTLY EXPRESSED UPON HYPOMETHYLATION OF SOME OF THESE DMRS IN CP-CML CELLS, AMONG WHICH 18 AND 81, RESPECTIVELY, WERE IN CP-CML CD34(+) CD15(-) CELLS ONLY. WE THEN VALIDATED THE DNA METHYLATION AND EXPRESSION DEFECTS OF SELECTED CANDIDATE GENES. SPECIFICALLY, WE IDENTIFIED GAS2, A CANDIDATE ONCOGENE, AS A NEW EXAMPLE OF GENE THE HYPOMETHYLATION OF WHICH IS ASSOCIATED WITH ROBUST OVEREXPRESSION IN CP-CML CELLS. ALTOGETHER, WE DEMONSTRATED THAT DNA METHYLATION ABNORMALITIES EXIST AT EARLY STAGES OF CML AND CAN AFFECT THE TRANSCRIPTIONAL LANDSCAPE OF MALIGNANT CELLS. THESE OBSERVATIONS COULD LEAD TO THE DEVELOPMENT OF COMBINATION TREATMENTS WITH EPIGENETIC DRUGS AND TKI FOR CP-CML.	2018	
                                                                                                                                                                                                                                                                                                                        
19 2327  39 EPIGENETIC REGULATION OF HUMAN CANCER/TESTIS ANTIGEN GENE, HAGE, IN CHRONIC MYELOID LEUKEMIA. BACKGROUND AND OBJECTIVES: CANCER TESTIS ANTIGENS (CTA) PROVIDE ATTRACTIVE TARGETS FOR CANCER-SPECIFIC IMMUNOTHERAPY. ALTHOUGH CTA GENES ARE EXPRESSED IN SOME NORMAL TISSUES, SUCH AS THE TESTIS, THIS IMMUNOLOGICALLY PROTECTED SITE LACKS MHC I EXPRESSION AND AS SUCH, DOES NOT PRESENT SELF ANTIGENS TO T CELLS. TO DATE, CTA GENES HAVE BEEN SHOWN TO BE EXPRESSED IN A RANGE OF SOLID TUMORS VIA DEMETHYLATION OF THEIR PROMOTER CPG ISLANDS, BUT RARELY IN CHRONIC MYELOID LEUKEMIA (CML) OR OTHER HEMATOLOGIC MALIGNANCIES. DESIGN AND METHODS: IN THIS STUDY, THE METHYLATION STATUS OF THE HAGE CTA GENE PROMOTER WAS ANALYZED BY QUANTITATIVE METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) AND SEQUENCING IN FOUR PHILADELPHIA-POSITIVE CELL LINES (TCC-S, K562, KU812 AND KYO-1) AND IN CML SAMPLES TAKEN FROM PATIENTS IN CHRONIC PHASE (CP N=215) OR BLAST CRISIS (BC N=47). HAGE EXPRESSION WAS ASSESSED BY QUANTITATIVE REVERSE TRANSCRIPTASE-POLYMERASE CHAIN REACTION. RESULTS: THE TCC-S CELL LINE SHOWED DEMETHYLATION OF HAGE THAT WAS ASSOCIATED WITH OVER-EXPRESSION OF THIS GENE. HAGE HYPOMETHYLATION WAS SIGNIFICANTLY MORE FREQUENT IN BC (46%) THAN IN CP (22%) (P=0.01) AND WAS CORRELATED WITH HIGH EXPRESSION LEVELS OF HAGE TRANSCRIPTS (P<0.0001). OF NOTE, IN CP-CML, EXTENSIVE HAGE HYPOMETHYLATION WAS ASSOCIATED WITH POORER PROGNOSIS IN TERMS OF CYTOGENETIC RESPONSE TO INTERFERON (P=0.01) OR IMATINIB (P=0.01), MOLECULAR RESPONSE TO IMATINIB (P=0.003) AND PROGRESSION-FREE SURVIVAL (P=0.05). INTERPRETATIONS AND CONCLUSION: THE METHYLATION STATUS OF THE HAGE PROMOTER DIRECTLY CORRELATES WITH ITS EXPRESSION IN BOTH CML CELL LINES AND PATIENTS AND IS ASSOCIATED WITH ADVANCED DISEASE AND POOR OUTCOME.	2007	
                                                                                                                                                                                                                                                                                                                                                                                                                                 
20 1629  26 DNMT3A ARG882 MUTATION DRIVES CHRONIC MYELOMONOCYTIC LEUKEMIA THROUGH DISTURBING GENE EXPRESSION/DNA METHYLATION IN HEMATOPOIETIC CELLS. THE GENE ENCODING DNA METHYLTRANSFERASE 3A (DNMT3A) IS MUTATED IN APPROXIMATELY 20% OF ACUTE MYELOID LEUKEMIA CASES, WITH ARG882 (R882) AS THE HOTSPOT. HERE, WE ADDRESSED THE TRANSFORMATION ABILITY OF THE DNMT3A-ARG882HIS (R882H) MUTANT BY USING A RETROVIRAL TRANSDUCTION AND BONE MARROW TRANSPLANTATION (BMT) APPROACH AND FOUND THAT THE MUTANT GENE CAN INDUCE ABERRANT PROLIFERATION OF HEMATOPOIETIC STEM/PROGENITOR CELLS. AT 12 MO POST-BMT, ALL MICE DEVELOPED CHRONIC MYELOMONOCYTIC LEUKEMIA WITH THROMBOCYTOSIS. RNA MICROARRAY ANALYSIS REVEALED ABNORMAL EXPRESSIONS OF SOME HEMATOPOIESIS-RELATED GENES, AND THE DNA METHYLATION ASSAY IDENTIFIED CORRESPONDING CHANGES IN METHYLATION PATTERNS IN GENE BODY REGIONS. MOREOVER, DNMT3A-R882H INCREASED THE CDK1 PROTEIN LEVEL AND ENHANCED CELL-CYCLE ACTIVITY, THEREBY CONTRIBUTING TO LEUKEMOGENESIS.	2014