1  574 111 BCR/ABL INCREASES EZH2 LEVELS WHICH REGULATES XIAP EXPRESSION VIA MIRNA-219 IN CHRONIC MYELOID LEUKEMIA CELLS. IN THIS STUDY, WE SHOWED THAT THE LEVELS OF EZH2 IN BONE MARROW MONONUCLEAR CELLS (BMMNCS) ISOLATED FROM INDIVIDUALS WITH CHRONIC MYELOID LEUKEMIA (CML) (N=12) WERE SIGNIFICANTLY GREATER THAN THOSE IN BMMNCS ISOLATED FROM HEALTHY VOLUNTEERS (N=6) AS WELL AS INDIVIDUALS WITH PHILADELPHIA CHROMOSOME-NEGATIVE MYELOPROLIFERATIVE NEOPLASMS. LENTIVIRAL TRANSDUCTION OF THE BCR/ABL GENE IN BA/F3 CELLS INCREASED EZH2 LEVELS IN PARALLEL WITH PHOSPHORYLATION OF STAT5. NOTABLY, CHROMATIN IMMUNOPRECIPITATION ASSAYS SHOWED THAT STAT5A BOUND TO A PROMOTER REGION OF THE EZH2 GENE, RESULTING IN AN INCREASE IN THE TRANSCRIPTIONAL ACTIVITY OF EZH2 IN LEUKEMIA CELLS. IMPORTANTLY, DOWNREGULATION OF EZH2 BY SHORT HAIRPIN RNAS (SHRNAS) INHIBITED THE EXPRESSION OF XIAP AND INCREASED THE MIR-219 LEVELS ASSOCIATED WITH A DECREASE IN HYPERMETHYLATION OF MIR-219-1 CPG ISLANDS. MOREOVER, OVEREXPRESSION OF MIR-219 DECREASED THE LEVELS OF XIAP IN CML CELLS. SINCE THE 3'-UNTRANSLATED REGION (3'-UTR) OF XIAP CONTAINS MIR219-5P-COMPLEMENTARY BINDING SITE, MIR-219 MIGHT MODULATE THE EXPRESSION OF XIAP THROUGH BINDING OF MIR-219 ON THE 3'-UTR OF XIAP. TAKEN TOGETHER, BCR/ABL POSITIVELY REGULATES THE EXPRESSION OF EZH2 VIA STAT5 SIGNALING. EZH2 MODULATES EPIGENETIC CHANGES AT DNA METHYLATED REGIONS ENCODING MIR-219 AND DOWNREGULATES THE LEVEL OF MIR-219, RESULTING IN UPREGULATION OF XIAP.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
2 3531  47 IMATINIB CAUSES EPIGENETIC ALTERATIONS OF PTEN GENE VIA UPREGULATION OF DNA METHYLTRANSFERASES AND POLYCOMB GROUP PROTEINS. WE HAVE RECENTLY REPORTED THE POSSIBLE IMATINIB-RESISTANT MECHANISM; LONG-TERM EXPOSURE OF LEUKEMIA CELLS TO IMATINIB DOWNREGULATED LEVELS OF PHOSPHATASE AND TENSIN HOMOLOG DELETED ON CHROMOSOME 10 (PTEN) VIA HYPERMETHYLATION OF ITS PROMOTER REGION (LEUKEMIA 2010; 24: 1631). THE PRESENT STUDY EXPLORED THE MOLECULAR MECHANISMS BY WHICH IMATINIB CAUSED METHYLATION ON THE PROMOTER REGION OF THIS TUMOR SUPPRESSOR GENE IN LEUKEMIA CELLS. REAL-TIME REVERSE TRANSCRIPTION PCR FOUND THAT LONG-TERM EXPOSURE OF CHRONIC EOSINOPHILIC LEUKEMIA EOL-1 CELLS EXPRESSING FIP1L1/PLATELET-DERIVED GROWTH FACTOR RECEPTOR-ALPHA TO IMATINIB INDUCED EXPRESSION OF DNA METHYLTRANSFERASE 3A (DNMT3A) AND HISTONE-METHYLTRANSFERASE ENHANCER OF ZESTE HOMOLOG 2 (EZH2), A FAMILY OF POLYCOMB GROUP, THEREBY INCREASING METHYLATION OF THE GENE. IMMUNOPRECIPITATION ASSAY FOUND THE INCREASED COMPLEX FORMATION OF DNMT3A AND EZH2 PROTEINS IN THESE CELLS. MOREOVER, CHROMATIN IMMUNOPRECIPITATION ASSAY SHOWED THAT AMOUNTS OF BOTH DNMT3A AND EZH2 PROTEINS BOUND AROUND THE PROMOTER REGION OF PTEN GENE WERE INCREASED IN EOL-1 CELLS AFTER EXPOSURE TO IMATINIB. FURTHERMORE, WE FOUND THAT LEVELS OF DNMT3A AND EZH2 WERE STRIKINGLY INCREASED IN LEUKEMIA CELLS ISOLATED FROM INDIVIDUALS WITH CHRONIC MYELOGENOUS LEUKEMIA (N=1) AND PHILADELPHIA CHROMOSOME-POSITIVE ACUTE LYMPHOBLASTIC LEUKEMIA (N=2), WHO RELAPSED AFTER TREATMENT WITH IMATINIB COMPARED WITH THOSE ISOLATED AT THEIR INITIAL PRESENTATION. TAKEN TOGETHER, IMATINIB COULD CAUSE DRUG-RESISTANCE VIA RECRUITMENT OF POLYCOMB GENE COMPLEX TO THE PROMOTER REGION OF THE PTEN AND DOWNREGULATION OF THIS GENE'S TRANSCRIPTS IN LEUKEMIA PATIENTS.	2011	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
3 3725  31 INHIBITION OF GLYCOGEN SYNTHASE KINASE-3 ACTIVITY LEADS TO EPIGENETIC SILENCING OF NUCLEAR FACTOR KAPPAB TARGET GENES AND INDUCTION OF APOPTOSIS IN CHRONIC LYMPHOCYTIC LEUKEMIA B CELLS. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS COMMONLY DEFINED AS A DISEASE OF FAILED APOPTOSIS OF B CELLS AND REMAINS AN INCURABLE DISEASE. THE MECHANISM OF RESISTANCE TO APOPTOSIS IN CLL IS COMPLEX AND INFLUENCED BY NUMEROUS FACTORS, INCLUDING NUCLEAR FACTOR KAPPAB (NFKAPPAB)-MEDIATED EXPRESSION OF ANTIAPOPTOTIC MOLECULES. RECENT EVIDENCE INDICATES THAT GLYCOGEN SYNTHASE KINASE-3BETA (GSK-3BETA) POSITIVELY REGULATES NFKAPPAB-MEDIATED GENE TRANSCRIPTION AND CELL SURVIVAL. USING MALIGNANT B CELLS COLLECTED FROM PATIENTS WITH CLL, WE FIND THAT BOTH GSK-3BETA AND NFKAPPAB ACCUMULATE IN THE NUCLEUS OF CLL B CELLS, AND PHARMACOLOGIC INHIBITION OF GSK-3 RESULTS IN DECREASED EXPRESSION OF TWO NFKAPPAB TARGET GENES BCL-2 AND XIAP AND A SUBSEQUENT INCREASE IN CLL B-CELL APOPTOSIS EX VIVO. FURTHERMORE, WE OBSERVED THAT INHIBITION OF GSK-3 LEADS TO A DECREASE IN NFKAPPAB-MEDIATED GENE TRANSCRIPTION BUT DOES NOT AFFECT THE NUCLEAR ACCUMULATION OF NFKAPPAB IN CLL B CELLS. LAST, USING CHROMATIN IMMUNOPRECIPITATION, WE SHOW THAT GSK-3 INHIBITION ABROGATES NFKAPPAB BINDING TO ITS TARGET GENE PROMOTERS (XIAP, BCL-2), IN PART THROUGH EPIGENETIC MODIFICATION OF HISTONES. OUR RESULTS ESTABLISH THAT INHIBITION OF GSK-3 ABROGATES NFKAPPAB BINDING TO ITS TARGET GENE PROMOTERS THROUGH AN EPIGENETIC MECHANISM, ENHANCES APOPTOSIS IN CLL B CELLS EX VIVO AND IDENTIFIES GSK-3 AS A POTENTIAL THERAPEUTIC TARGET IN THE TREATMENT OF CLL.	2007	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
4 5458  34 RESEARCH ON EPIGENETIC MECHANISM OF SFRP2 IN ADVANCED CHRONIC MYELOID LEUKEMIA. SECRETED FRIZZLED-RELATED PROTEIN 2 (SFRP2) HAS BEEN REPORTED TO ACT AS A TUMOR SUPPRESSORS. THIS STUDY AIMS TO DETECT THE BIOLOGICAL ROLE OF SFRP2 IN ADVANCED CHRONIC MYELOID LEUKEMIA (CML). IN THIS STUDY WE EXAMINED BONE MARROW SAMPLES FROM 45 CML PATIENTS AND 10 HEALTHY DONORS. K562 AND KCL22 CELLS WERE CULTURED AND TREATED WITH DEMETHYLATION DRUG AND HISTONE DEACETYLASE INHIBITOR (HDACI). KCL22 AND K562 CELLS WERE TRANSFECTED WITH LENTIVIRAL VECTOR (LV)-SFRP2, LV-CONTROL. THE CELLS WERE THEN SUBJECTED TO PROLIFERATION AND APOPTOSIS ASSAYS, REAL TIME POLYMERASE CHAIN REACTION (PCR), METHYLATION-SPECIFIC PCR (MSP), WESTERN BLOTTING, CO-IMMUNOPRECIPITATION (COIP) AND CHROMATIN IMMUNOPRECIPITATION (CHIP), WE FOUND THAT SFRP2 WAS DOWN-REGULATED IN THE ACCELERATED AND BLAST PHASE OF CML, WHEREAS, THE LEVELS OF WNT1, WNT3 AND WNT5A WERE UP-REGULATED IN THE ACCELERATED AND BLAST PHASE OF CML. OVEREXPRESSION SFRP2 INHIBITED PROLIFERATION, PROMOTED APOPTOSIS AND ACTIVATED THE WNT PATHWAY. COIP-MS RESULTS SHOWED THAT SFRP2 INTERACTED WITH WNT1 AND WNT5A. CHIP-SEQ RESULT INDICATED THAT THE PROMOTER OF H3K4ME3 AND H3K27ME3 WERE ABLE TO INTERACT WITH SFRP2. IN CONCLUSION, OUR FINDINGS DEMONSTRATED THE SFRP2 ACT AS A POTENTIAL THERAPEUTIC TARGET FOR ADVANCED CML. FURTHERMORE, OUR RESULTS SUPPORT THE USE OF DEMETHYLATION DRUGS AND HDACI AS A POTENTIAL CML TREATMENT STRATEGY.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
5 1669  32 DOWNREGULATION OF THE HISTONE METHYLTRANSFERASE SETD2 PROMOTES IMATINIB RESISTANCE IN CHRONIC MYELOID LEUKAEMIA CELLS. OBJECTIVES: EPIGENETIC MODIFIERS WERE IMPORTANT PLAYERS IN THE DEVELOPMENT OF HAEMATOLOGICAL MALIGNANCIES AND SENSITIVITY TO THERAPY. MUTATIONS OF SET DOMAIN-CONTAINING 2 (SETD2), A METHYLTRANSFERASE THAT CATALYSES THE TRIMETHYLATION OF HISTONE 3 ON LYSINE 36 (H3K36ME3), WERE FOUND IN VARIOUS MYELOID MALIGNANCIES. HOWEVER, THE DETAILED MECHANISMS THROUGH WHICH SETD2 CONFERS CHRONIC MYELOID LEUKAEMIA PROGRESSION AND RESISTANCE TO THERAPY TARGETING ON BCR-ABL REMAIN UNCLEAR. MATERIALS AND METHODS: THE LEVEL OF SETD2 IN IMATINIB-SENSITIVE AND IMATINIB-RESISTANT CHRONIC MYELOID LEUKAEMIA (CML) CELLS WAS EXAMINED BY IMMUNOBLOTTING AND QUANTITATIVE REAL-TIME PCR. WE ANALYSED CD34(+) CD38(-) LEUKAEMIC STEM CELLS BY FLOW CYTOMETRY AND COLONY FORMATION ASSAYS UPON SETD2 KNOCKDOWN OR OVEREXPRESSION. THE IMPACT OF SETD2 EXPRESSION ALTERATIONS OR SMALL-MOLECULE INHIBITOR JIB-04 TARGETING H3K36ME3 LOSS ON IMATINIB SENSITIVITY WAS ASSESSED BY IC50, CELL APOPTOSIS AND PROLIFERATION ASSAYS. FINALLY, RNA SEQUENCING AND CHIP-QUANTITATIVE PCR WERE PERFORMED TO VERIFY PUTATIVE DOWNSTREAM TARGETS. RESULTS: SETD2 WAS FOUND TO ACT AS A TUMOUR SUPPRESSOR IN CML. THE NOVEL ONCOGENIC TARGETS MYCN AND ERG WERE SHOWN TO BE THE DIRECT DOWNSTREAM TARGETS OF SETD2, WHERE THEIR OVEREXPRESSION INDUCED BY SETD2 KNOCKDOWN CAUSED IMATINIB INSENSITIVITY AND LEUKAEMIC STEM CELL ENRICHMENT IN CML CELL LINES. TREATMENT WITH JIB-04, AN INHIBITOR THAT RESTORES H3K36ME3 LEVELS THROUGH BLOCKADE OF ITS DEMETHYLATION, SUCCESSFULLY IMPROVED THE CELL IMATINIB SENSITIVITY AND ENHANCED THE CHEMOTHERAPEUTIC EFFECT. CONCLUSIONS: OUR STUDY NOT ONLY EMPHASIZES THE REGULATORY MECHANISM OF SETD2 IN CML, BUT ALSO PROVIDES PROMISING THERAPEUTIC STRATEGIES FOR OVERCOMING THE IMATINIB RESISTANCE IN PATIENTS WITH CML.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
6 3982  46 LONG-TERM EXPOSURE OF LEUKEMIA CELLS TO MULTI-TARGETED TYROSINE KINASE INHIBITOR INDUCES ACTIVATIONS OF AKT, ERK AND STAT5 SIGNALING VIA EPIGENETIC SILENCING OF THE PTEN GENE. IMATINIB INDUCES COMPLETE MOLECULAR RESPONSE IN PATIENTS WITH CHRONIC MYELOID LEUKEMIA (CML) AND CHRONIC EOSINOPHILIC LEUKEMIA (CEL). HOWEVER, DEVELOPMENT OF RESISTANCE TO IMATINIB HAS EMERGED AS AN IMPORTANT CLINICAL PROBLEM FOR MOLECULAR-TARGETED THERAPY IN CML AND CEL. IN THIS STUDY, WE HAVE ESTABLISHED THE IMATINIB-RESISTANT CEL EOL-1 SUB-LINES (DESIGNATED AS EOL-1R) BY CULTURING CELLS WITH INCREASING CONCENTRATIONS OF IMATINIB FOR 6 MONTHS. INTERESTINGLY, EOL-1R CELLS SHOWED EPIGENETIC SILENCING OF THE PHOSPHATASE AND TENSIN HOMOLOG DELETED ON CHROMOSOME TEN (PTEN) GENE. EXPOSURE OF EOL-1R CELLS TO IMATINIB FAILED TO DEPHOSPHORYLATE AKT, ERK AND STAT5, ALTHOUGH PDGFRALPHA WAS EFFECTIVELY INACTIVATED. THE FORCED EXPRESSION OF PTEN NEGATIVELY REGULATED THESE SIGNAL PATHWAYS AND SENSITIZED EOL-1R CELLS TO IMATINIB. NOTABLY, HYPERMETHYLATION OF THE PROMOTER REGION OF THE PTEN GENE IN ASSOCIATION WITH THE DOWNREGULATION OF THIS GENE'S TRANSCRIPTS WAS IDENTIFIED IN IMATINIB-RESISTANT LEUKEMIA CELLS ISOLATED FROM INDIVIDUALS WITH CEL, CML AND PHILADELPHIA-POSITIVE ACUTE LYMPHOBLASTIC LEUKEMIA. IN ADDITION, ANTI-EPIGENETIC AGENTS RESTORED PTEN EXPRESSION, RESULTING IN THE SENSITIZATION OF EOL-1R CELLS TO IMATINIB. TAKEN TOGETHER, EPIGENETIC SILENCE OF PTEN IS ONE OF THE MECHANISMS THAT CAUSE DRUG RESISTANCE IN INDIVIDUALS WITH LEUKEMIA AFTER EXPOSURE TO IMATINIB. ANTI-EPIGENETIC AGENTS MAY BE USEFUL FOR OVERCOMING DRUG RESISTANCE IN SUCH A CASE.	2010	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
7 4877  35 OVEREXPRESSION OF MIR-4433 BY SUBEROYLANILIDE HYDROXAMIC ACID SUPPRESSES GROWTH OF CML CELLS AND INDUCES APOPTOSIS THROUGH TARGETING BCR-ABL. BACKGROUND: TARGETING BCR-ABL IS THE KEY FOR THE TREATMENT OF CML. ALTHOUGH GREAT PROGRESS HAS BEEN ACHIEVED FOR THE TREATMENT OF CML PATIENTS IN CHRONIC STAGE, EFFECTIVE DRUGS WITH GOOD SAFETY ARE NOT AVAILABLE FOR THOSE IN ADVANCED STAGES OF CML PATIENTS. IN PRESENT STUDY, A HISTONE DEACETYLASE INHIBITOR, SUBEROYLANILIDE HYDROXAMIC ACID (SAHA), WAS USED TO SCREEN FOR MICRORNA THAT CAN TARGET BCR-ABL. METHODS: RT-QPCR WAS USED TO DETERMINE BCR-ABL AND MIR-4433 TRANSCRIPTION LEVEL IN CML CELLS. IN CML CELLS, PROTEINS INCLUDING PARP, CASPASE-3, ACETYL-HISTONE 3, HISTONE 3 AND BCR-ABL, AS WELL AS BCR-ABL DOWNSTREAM PROTEINS WERE DETECTED USING WESTERN BLOT. CELL VIABILITY AND APOPTOSIS WERE MONITORED RESPECTIVELY BY MTS ASSAY AND FLOW CYTOMETRY. THE CORRELATION BETWEEN MIR-4433 AND BCR-ABL WAS DETERMINED BY LUCIFERASE REPORTER ASSAY. THE ANTI-TUMOR EFFECT OF MIR-4433 TO K562 CELLS WAS EVALUATED BY NUDE MOUSE XENOGRAFT MODEL IN VIVO. RESULTS: SAHA UP-REGULATED THE ACETYLATION LEVEL OF HISTONE 3, AND EFFECTIVELY INHIBITED BCR-ABL MRNA LEVEL AND ITS DOWNSTREAM SIGNAL TRANSDUCTION PATHWAY, WHILE INHIBITING THE GROWTH OF CML CELLS AND INDUCING APOPTOSIS. FURTHERMORE, BIOINFORMATICS TOOLS PREDICTED THAT MIR-4433 IS A PUTATIVE MICRORNA TARGETING BCR-ABL AND THAT THE EXPRESSION LEVEL OF MIR-4433 WAS SIGNIFICANTLY INCREASED AFTER SAHA TREATMENT IN K562 CELLS. LUCIFERASE ACTIVITY ANALYSIS REVEALED THAT MIR-4433 DIRECTLY TARGETS BCR-ABL. ADDITIONALLY, TRANSIENT EXPRESSION OF MIR-4433 ABROGATED BCR-ABL ACTIVITY AND ITS DOWNSTREAM SIGNALING PATHWAYS WHILE INDUCING APOPTOSIS IN K562 CELLS. MOREOVER, STABLE EXPRESSION OF MIR-4433 SUPPRESSED BCR-ABL AND ITS DOWNSTREAM SIGNALING PATHWAY, AND INHIBITED THE GROWTH OF K562 CELLS IN VITRO AND THE GROWTH OF K562-XENOGRAFTS IN NUDE MICE. CONCLUSION: MIR-4433 WAS IDENTIFIED AS A MICRORNA TARGETING BCR-ABL, WHICH MAY BE SUBJECT TO EPIGENETIC REGULATION OF SAHA, A HISTONE DEACETYLASE INHIBITOR THAT HAS BEEN APPROVED BY THE US FDA FOR THE TREATMENT OF CUTANEOUS T-CELL LYMPHOMA. THE FINDINGS OF THIS STUDY PROVIDE A MOLECULAR BASIS FROM ANOTHER ANGLE FOR THE USE OF SAHA IN THE TREATMENT OF CML.	2019	
                                                                                                     
8 1733  34 E-CADHERIN GENE RE-EXPRESSION IN CHRONIC LYMPHOCYTIC LEUKEMIA CELLS BY HDAC INHIBITORS. BACKGROUND: THE TUMOR SUPPRESSOR GENE E-CADHERIN GENE IS FREQUENTLY SILENCED IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) CELLS AND RESULTS IN WNT-PATHWAY ACTIVATION. WE ANALYZED THE ROLE OF HISTONE EPIGENETIC MODIFICATIONS IN E-CADHERIN GENE SILENCING. METHODS: CLL SPECIMENS WERE TREATED WITH HISTONE DEACETYLASE INHIBITOR (HDACI) MS-275 AND ANALYZED FOR E-CADHERIN EXPRESSION WITH WESTERN BLOT AND RT-PCR ANALYSIS. THE DOWNSTREAM EFFECTS OF HDACI TREATED LEUKEMIC CELLS WERE STUDIED BY ANALYZING THE EFFECT ON WNT-PATHWAY SIGNALING. HDACI INDUCED ALTERATIONS IN E-CADHERIN SPLICING WERE INVESTIGATED BY TRANSCRIPT SPECIFIC REAL TIME PCR ANALYSIS. RESULTS: TREATMENT OF CLL SPECIMENS WITH HISTONE DEACETYLASE INHIBITORS (HDACI) TREATMENT RESULTED IN AN INCREASE OF THE E-CADHERIN RNA TRANSCRIPT (5 TO 119 FOLD INCREASE, N=10) IN EIGHT OUT OF TEN CLL SPECIMENS INDICATING THAT THIS GENE IS DOWN REGULATED BY HISTONE HYPOACETYLATION IN A MAJORITY OF CLL SPECIMENS. THE E-CADHERIN RE-EXPRESSION IN CLL SPECIMENS WAS NOTED BY WESTERN BLOT ANALYSIS AS WELL. BESIDES EPIGENETIC SILENCING ANOTHER MECHANISM OF E-CADHERIN INACTIVATION IS ABERRANT EXON 11 SPLICING RESULTING IN AN ALTERNATIVELY SPLICED TRANSCRIPT THAT LACKS EXON 11 AND IS DEGRADED BY THE NON-SENSE MEDIATED DECAY (NMD) PATHWAY. OUR CHROMATIN IMMUNOPRECIPITATION EXPERIMENTS SHOW THAT HDACI INCREASED THE ACETYLATION OF HISTONES H3 AND H4 IN THE E-CADHERIN PROMOTER REGION. THIS ALSO AFFECTED THE E-CADHERIN EXON 11 SPLICING PATTERN AS HDACI TREATED CLL SPECIMENS PREFERENTIALLY EXPRESSED THE CORRECTLY SPLICED TRANSCRIPT AND NOT THE EXON 11 SKIPPED ABERRANT TRANSCRIPT. THE RE-EXPRESSED E- CADHERIN BINDS TO BETA-CATENIN WITH INHIBITION OF THE ACTIVE WNT-BETA-CATENIN PATHWAY IN THESE CELLS. THIS RESULTED IN A DOWN REGULATION OF TWO WNT TARGET GENES, LEF AND CYCLIND1 AND THE WNT PATHWAY REPORTER. CONCLUSION: THE E-CADHERIN GENE IS EPIGENETICALLY MODIFIED AND HYPOACETYLATED IN CLL LEUKEMIC CELLS. TREATMENT OF CLL SPECIMENS WITH HDACI MS-275 ACTIVATES TRANSCRIPTION FROM THIS SILENT GENE WITH EXPRESSION OF MORE CORRECTLY SPLICED E-CADHERIN TRANSCRIPTS AS COMPARED TO THE ABERRANT EXON11 SKIPPED TRANSCRIPTS THAT IN TURN INHIBITS THE WNT SIGNALING PATHWAY. THE DATA HIGHLIGHTS THE ROLE OF EPIGENETIC MODIFICATIONS IN ALTERING GENE SPLICING PATTERNS.	2013	

9 6238  38 THE MALIGNANCY SUPPRESSION ROLE OF MIR-23A BY TARGETING THE BCR/ABL ONCOGENE IN CHROMIC MYELOID LEUKEMIA. THE AIM OF THIS STUDY WAS TO INVESTIGATE THE ROLE AND MECHANISM OF MIR-23A IN THE REGULATION OF BCR/ABL AND TO PROVIDE A NEW PROGNOSTIC BIOMARKER FOR CHRONIC MYELOID LEUKEMIA (CML). THE EXPRESSION LEVELS OF MIR-23A AND BCR/ABL WERE ASSESSED IN 42 NEWLY DIAGNOSED CML PATIENTS, 37 CML PATIENTS IN FIRST COMPLETE REMISSION AND 25 HEALTHY CONTROLS. QUANTITATIVE REAL-TIME PCR, WESTERN BLOT ANALYSIS AND COLONY FORMATION ASSAY WERE USED TO EVALUATE CHANGES INDUCED BY OVEREXPRESSION OR INHIBITION OF MIR-23A OR BCR/ABL. MIR-23A MIMIC OR NEGATIVE CONTROL MIMIC WAS TRANSFECTED INTO A CML CELL LINE (K562) AND TWO LUNG CANCER CELL LINES (H157 AND SKMES1) USING LIPOFECTAMINE 2000, AND THE CELLS WERE USED FOR REAL-TIME REVERSE TRANSCRIPTION-PCR (RT-PCR) AND WESTERN BLOT ANALYSIS. WE FOUND THAT THE DOWNREGULATION OF MIR-23A EXPRESSION WAS A FREQUENT EVENT IN BOTH LEUKEMIA CELL LINES AND PRIMARY LEUKEMIC CELLS FROM PATIENTS WITH DE NOVO CML. THE MICROARRAY RESULTS SHOWED THAT MOST OF THE CML PATIENTS EXPRESSED HIGH LEVELS OF BCR/ABL AND LOW LEVELS OF MIR-23A. REAL-TIME RT-PCR AND WESTERN BLOT ANALYSIS SHOWED THAT THE BCR/ABL LEVELS IN MIR-23A-TRANSFECTED CELLS WERE LOWER THAN THOSE IN THE CONTROL GROUPS. ECTOPIC EXPRESSION OF MIR-23A IN K562 CELLS LED TO CELLULAR SENESCENCE. MOREOVER, WHEN K562 CELLS WERE TREATED WITH 5-AZA-2'-DEOXYCYTIDINE, A DNA METHYLATION INHIBITOR, BCR/ABL EXPRESSION WAS UPREGULATED, WHICH INDICATES EPIGENETIC SILENCING OF MIR-23A IN LEUKEMIC CELLS. BCR/ABL AND MIR-23A EXPRESSIONS WERE INVERSELY RELATED TO CML, AND BCR/ABL EXPRESSION WAS REGULATED BY MIR-23A IN LEUKEMIC CELLS. THE EPIGENETIC SILENCING OF MIR-23A LED TO DEREPRESSION OF BCR/ABL EXPRESSION, AND CONSEQUENTLY CONTRIBUTES TO CML DEVELOPMENT AND PROGRESSION.	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
10  139  31 ABERRANT DNA METHYLATION IS ASSOCIATED WITH DISEASE PROGRESSION, RESISTANCE TO IMATINIB AND SHORTENED SURVIVAL IN CHRONIC MYELOGENOUS LEUKEMIA. THE EPIGENETIC IMPACT OF DNA METHYLATION IN CHRONIC MYELOGENOUS LEUKEMIA (CML) IS NOT COMPLETELY UNDERSTOOD. TO ELUCIDATE ITS ROLE WE ANALYZED 120 PATIENTS WITH CML FOR METHYLATION OF PROMOTER-ASSOCIATED CPG ISLANDS OF 10 GENES. FIVE GENES WERE IDENTIFIED BY DNA METHYLATION SCREENING IN THE K562 CELL LINE AND 3 GENES IN PATIENTS WITH MYELOPROLIFERATIVE NEOPLASMS. THE CDKN2B GENE WAS SELECTED FOR ITS FREQUENT METHYLATION IN MYELOID MALIGNANCIES AND ABL1 AS THE TARGET OF BCR-ABL TRANSLOCATION. THIRTY PATIENTS WERE IMATINIB-NAIVE (MOSTLY TREATED BY INTERFERON-ALPHA BEFORE THE IMATINIB ERA), 30 WERE IMATINIB-RESPONSIVE, 50 WERE IMATINIB-RESISTANT, AND 10 WERE IMATINIB-INTOLERANT. WE QUANTIFIED DNA METHYLATION BY BISULFITE PYROSEQUENCING. THE AVERAGE NUMBER OF METHYLATED GENES WAS 4.5 PER PATIENT IN THE CHRONIC PHASE, INCREASING SIGNIFICANTLY TO 6.2 IN THE ACCELERATED AND 6.4 IN THE BLASTIC PHASE. HIGHER NUMBERS OF METHYLATED GENES WERE ALSO OBSERVED IN PATIENTS RESISTANT OR INTOLERANT TO IMATINIB. THESE PATIENTS ALSO SHOWED ALMOST EXCLUSIVE METHYLATION OF A PUTATIVE TRANSPORTER OSCP1. ABNORMAL METHYLATION OF A SRC SUPPRESSOR GENE PDLIM4 WAS ASSOCIATED WITH SHORTENED SURVIVAL INDEPENDENTLY OF CML STAGE AND IMATINIB RESPONSIVENESS. WE CONCLUDE THAT ABERRANT DNA METHYLATION IS ASSOCIATED WITH CML PROGRESSION AND THAT DNA METHYLATION COULD BE A MARKER ASSOCIATED WITH IMATINIB RESISTANCE. FINALLY, DNA METHYLATION OF PDLIM4 MAY HELP IDENTIFY A SUBSET OF CML PATIENTS THAT WOULD BENEFIT FROM TREATMENT WITH SRC/ABL INHIBITORS.	2011	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
11 6402  26 THE ROLES OF EPIGENETIC MODIFICATIONS OF PROAPOPTOTIC BID AND BIM GENES IN IMATINIB-RESISTANT CHRONIC MYELOID LEUKEMIA CELLS. IN CHRONIC MYELOID LEUKEMIA (CML), EPIGENETIC MODIFICATIONS SUCH AS PROMOTER HYPERMETHYLATION AND INACTIVE HISTONE MODIFICATION ARE KNOWN MECHANISMS OF DRUG RESISTANCE. IN OUR STUDY, WE INVESTIGATED THE ROLES OF PROMOTER HYPERMETHYLATION OF BIM AND BID GENES AND H3K27ME3 HISTONE MODIFICATION ON IMATINIB RESISTANCE. WE DETECTED HIGHER EXPRESSION LEVELS OF BIM AND BID GENES AND LOWER EXPRESSION LEVELS OF EZH2, EED2, SIRT1, AND SUZ12 GENES IN IMATINIB-RESISTANT K562/IMA-3 CELLS COMPARED TO IMATINIB-NON-RESISTANT K562 CELLS. WHILE WE DETERMINED THE EZH2 AND DNMT ENZYMES AS BOUNDED TO THE PROMOTER OF THE BIM GENE, WE DID NOT DETECT HYPERMETHYLATION OF THIS PROMOTER. WE ALSO FOUND THE H3K27ME3 HISTONE MODIFICATION PROMOTER OF BIM AND BID GENES IN BOTH CELL LINES. IN CONCLUSION, OUR RESULTS SUPPORT THE NOTION THAT DNA PROMOTER METHYLATION MAY BE FORMED INDEPENDENTLY FROM EZH2-H3K27ME3 AND PRO-APOPTOTIC BIM AND BID GENES ARE NOT METHYLLATED IN THE IMATINIB RESISTANCE OF CML CELLS.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
12 1613  29 DNA METHYLTRANSFERASE 1 MEDIATED ABERRANT METHYLATION AND SILENCING OF SHP-1 GENE IN CHRONIC MYELOGENOUS LEUKEMIA CELLS. INTRODUCTION: EXTENSIVE STUDIES ON SHP-1 PROTEIN AND SHP-1 MRNA REVEALED THAT THE DIMINISHMENT OR ABOLISHMENT OF THE EXPRESSION OF SHP-1 IN LEUKEMIAS/LYMPHOMAS WAS DUE TO ABERRANT PROMOTER METHYLATION. THUS FAR, THE MECHANISM OF EPIGENETIC SILENCING OF THE SHP-1 TYROSINE PHOSPHATASE GENE THAT OCCURS IN CHRONIC MYELOGENOUS LEUKEMIA CELLS REMAINS POORLY UNDERSTOOD. METHODS: THE EXPRESSIONS OF THE TARGET MOLECULES WERE DETERMINED BY QUANTITATIVE REAL TIME PCR AND WESTERN BLOT, RESPECTIVELY. BISULFITE SEQUENCING PCR WAS USED TO DETECT METHYLATION STATUS OF DNA CPG. THE LENTIVIRAL VECTORS WERE APPLIED TO MODIFY GENE EXPRESSION. RESULTS: IN THE PRESENT STUDY, WE FOUND THAT THE PROMOTER 2 OF SHP-1 GENE IS LOCATED BETWEEN POSITIONS FROM -577BP TO +300BP, AND 22 CPG SITES CONTAINED IN POSITIONS -353BP APPROXIMATELY +182BP ARE ABERRANTLY METHYLATED IN K562 CELLS. IN VITRO, WE DEMONSTRATED THAT DNMT1 SILENCING INDUCED DEMETHYLATION OF THE 22 CPG SITES LOCATED IN THE SHP-1 PROMOTER AND RE-EXPRESSION OF SHP-1 GENE IN K562 CELLS. MOREOVER, WE PROVED THAT THE EXPRESSION LEVELS OF DNMT1 AND SHP-1 MRNA AND PROTEIN WERE NEGATIVELY CORRELATED IN K562 CELLS AND BM ASPIRATES MONONUCLEAR CELLS FROM CML PATIENTS. CONCLUSION: COLLECTIVELY, THESE RESULTS INDICATE THAT DNMT1 MEDIATES ABERRANT METHYLATION AND SILENCING OF SHP-1 GENE IN CHRONIC MYELOGENOUS LEUKEMIA CELLS, AND PROVIDE A NOVEL THERAPEUTIC TARGET FOR CML.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
13 5669  21 SFRP1 PROMOTER METHYLATION IS ASSOCIATED WITH PERSISTENT PHILADELPHIA CHROMOSOME IN CHRONIC MYELOID LEUKEMIA. EPIGENETIC SILENCING OF SFRP GENES HAS BEEN SHOWN TO LEAD TO CONSTITUTIVE ACTIVATION OF THE CANONICAL WNT-SIGNALING PATHWAY. THE FIRST DESCRIPTION OF DEREGULATED WNT-SIGNALING ACTIVATION IN A HEMATOLOGICAL MALIGNANCY WAS REPORTED IN CHRONIC MYELOID LEUKEMIA (CML). TO INVESTIGATE WHETHER EPIGENETIC SILENCING OF SFRP IS RESPONSIBLE FOR THE OBSERVED WNT ACTIVATION IN CML, WE STUDIED THE METHYLATION AND MUTATIONAL STATUS OF THE SFRP1 PROMOTER IN 48 CHRONIC PHASE CML PATIENTS. OF THE 48 CML PATIENTS 41 WERE SHOWN TO BE UNMETHYLATED, 6 PATIENTS HEMI-METHYLATED AND 1 PATIENT FULLY METHYLATED AT THE SFRP1 PROMOTER. ALBEIT OBSERVED INFREQUENTLY IN CHRONIC PHASE CML, SFRP1 PROMOTER METHYLATION CORRELATED WITH PRIMARY CYTOGENETIC RESISTANCE TO IMATINIB MESYLATE. SFRP1 PROMOTER METHYLATION MAY INDICATE A GENETICALLY MORE UNSTABLE FORM OF DISEASE RESISTANT TO THERAPY AND PROVIDE A KEY BIOLOGICAL DIFFERENCE IN THERAPY RESISTANT PATIENTS, IN ADDITION TO A POSSIBLE MECHANISM FOR THE OBSERVED ACTIVATION OF CANONICAL WNT SIGNALING IN CML.	2009	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
14 3415  35 HSP90 INHIBITION INCREASES SOCS3 TRANSCRIPT AND REGULATES MIGRATION AND CELL DEATH IN CHRONIC LYMPHOCYTIC LEUKEMIA. EPIGENETIC OR TRANSCRIPTIONAL SILENCING OF IMPORTANT TUMOR SUPPRESSORS HAS BEEN DESCRIBED TO CONTRIBUTE TO CELL SURVIVAL AND TUMORIGENESIS IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). USING GENE EXPRESSION MICROARRAY ANALYSIS, WE FOUND THAT THOUSANDS OF GENES ARE REPRESSED MORE THAN 2-FOLD IN CLL COMPARED TO NORMAL B CELLS; HOWEVER THERAPEUTIC APPROACHES TO REVERSE THIS HAVE BEEN LIMITED IN CLL. FOLLOWING TREATMENT WITH THE HSP90 INHIBITOR 17-DMAG, A SIGNIFICANT NUMBER OF THESE REPRESSED GENES WERE SIGNIFICANTLY RE-EXPRESSED. ONE OF THE GENES SIGNIFICANTLY REPRESSED IN CLL AND UP-REGULATED BY 17-DMAG WAS SUPPRESSOR OF CYTOKINE SIGNALING 3, (SOCS3). SOCS3 HAS BEEN SHOWN TO BE SILENCED IN SOLID TUMORS AS WELL AS MYELOID LEUKEMIA; HOWEVER LITTLE IS KNOWN ABOUT THE REGULATION IN CLL. WE FOUND THAT 17-DMAG INDUCES EXPRESSION OF SOCS3 BY VIA THE ACTIVATION OF P38 SIGNALING, AND SUBSEQUENTLY INHIBITS AKT AND STAT3 PHOSPHORYLATION RESULTING IN DOWNSTREAM EFFECTS ON CELL MIGRATION AND SURVIVAL. WE THEREFORE SUGGEST THAT SOCS3 IS AN IMPORTANT SIGNALING PROTEIN IN CLL, AND HSP90 INHIBITORS REPRESENT A NOVEL APPROACH TO TARGET TRANSCRIPTIONAL REPRESSION IN B CELL LYMPHOPROLIFERATIVE DISORDERS WHICH EXHIBIT A SUBSTANTIAL DEGREE OF GENE REPRESSION.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
15 2081  28 EPIGENETIC DOWN-REGULATION OF BIM EXPRESSION IS ASSOCIATED WITH REDUCED OPTIMAL RESPONSES TO IMATINIB TREATMENT IN CHRONIC MYELOID LEUKAEMIA. BACKGROUND: EXPRESSION OF THE PRO-APOPTOTIC BCL-2-INTERACTING MEDIATOR (BIM) HAS RECENTLY BEEN IMPLICATED IN IMATINIB-INDUCED APOPTOSIS OF BCR-ABL1(+) CELLS. HOWEVER, THE MECHANISMS INVOLVED IN THE REGULATION OF BIM IN CML AND ITS ROLE IN THE CLINICAL SETTING HAVE NOT BEEN ESTABLISHED. DESIGN AND METHODS: WE ANALYSED THE MRNA EXPRESSION OF BIM IN 100 NEWLY DIAGNOSED PATIENTS WITH CML IN CHRONIC PHASE BY Q-RT-PCR AND THE PROTEIN LEVELS BY WESTERN BLOT ANALYSIS. METHYLATION STATUS WAS ANALYSED BY BISULPHITE GENOMIC SEQUENCING AND MSP. CML CELL LINES WERE TREATED WITH IMATINIB AND 5-AZA-2'-DEOXYCYTIDINE, AND WERE TRANSFECTED WITH TWO DIFFERENT SIRNAS AGAINST BIM AND CELL PROLIFERATION AND APOPTOSIS WERE ANALYSED. RESULTS: WE DEMONSTRATED THAT DOWN-REGULATION OF BIM EXPRESSION WAS PRESENT IN 36% OF THE PATIENTS AND WAS SIGNIFICANTLY ASSOCIATED WITH A LACK OF OPTIMAL RESPONSE TO IMATINIB AS INDICATED BY THE DECREASE IN CYTOGENETIC AND MOLECULAR RESPONSES AT 6, 12 AND 18 MONTHS IN COMPARISON WITH PATIENTS WITH NORMAL BIM EXPRESSION (P<0.05). EXPRESSION OF BIM WAS MEDIATED BY PROMOTER HYPERMETHYLATION AS DEMONSTRATED BY RESTORATION OF BIM EXPRESSION AFTER TREATMENT OF CML CELLS WITH 5-AZA-2'-DEOXYCYTIDINE. USING CML CELL LINES WITH LOW AND NORMAL EXPRESSION OF BIM WE FURTHER DEMONSTRATED THAT THE EXPRESSION OF BIM IS REQUIRED FOR IMATINIB-INDUCED CML APOPTOSIS. CONCLUSION: OUR DATA INDICATE THAT DOWN-REGULATION OF BIM IS EPIGENETICALLY CONTROLLED BY METHYLATION IN A PERCENTAGE OF CML PATIENTS AND HAS AN UNFAVOURABLE PROGNOSTIC IMPACT, AND THAT THE COMBINATION OF IMATINIB WITH A DE-METHYLATING AGENT MAY RESULT IN IMPROVED RESPONSES IN PATIENTS WITH DECREASED EXPRESSION OF BIM.	2009	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
16  206  38 ACTIVATION OF NOTCH AND MYC SIGNALING VIA B-CELL-RESTRICTED DEPLETION OF DNMT3A GENERATES A CONSISTENT MURINE MODEL OF CHRONIC LYMPHOCYTIC LEUKEMIA. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY DISORDERED DNA METHYLATION, SUGGESTING THESE EPIGENETIC CHANGES MIGHT PLAY A CRITICAL ROLE IN DISEASE ONSET AND PROGRESSION. THE METHYLTRANSFERASE DNMT3A IS A KEY REGULATOR OF DNA METHYLATION. ALTHOUGH DNMT3A SOMATIC MUTATIONS IN CLL ARE RARE, WE FOUND THAT LOW DNMT3A EXPRESSION IS ASSOCIATED WITH MORE AGGRESSIVE DISEASE. A CONDITIONAL KNOCKOUT MOUSE MODEL SHOWED THAT HOMOZYGOUS DEPLETION OF DNMT3A FROM B CELLS RESULTS IN THE DEVELOPMENT OF CLL WITH 100% PENETRANCE AT A MEDIAN AGE OF ONSET OF 5.3 MONTHS, AND HETEROZYGOUS DNMT3A DEPLETION YIELDS A DISEASE PENETRANCE OF 89% WITH A MEDIAN ONSET AT 18.5 MONTHS, CONFIRMING ITS ROLE AS A HAPLOINSUFFICIENT TUMOR SUPPRESSOR. B1A CELLS WERE CONFIRMED AS THE CELL OF ORIGIN OF DISEASE IN THIS MODEL, AND DNMT3A DEPLETION RESULTED IN FOCAL HYPOMETHYLATION AND ACTIVATION OF NOTCH AND MYC SIGNALING. AMPLIFICATION OF CHROMOSOME 15 CONTAINING THE MYC GENE WAS DETECTED IN ALL CLL MICE TESTED, AND INFILTRATION OF HIGH-MYC-EXPRESSING CLL CELLS IN THE SPLEEN WAS OBSERVED. NOTABLY, HYPERACTIVATION OF NOTCH AND MYC SIGNALING WAS EXCLUSIVELY OBSERVED IN THE DNMT3A CLL MICE, BUT NOT IN THREE OTHER CLL MOUSE MODELS TESTED (SF3B1-ATM, IKZF3, AND MDR), AND DNMT3A-DEPLETED CLL WERE SENSITIVE TO PHARMACOLOGIC INHIBITION OF NOTCH SIGNALING IN VITRO AND IN VIVO. CONSISTENT WITH THESE FINDINGS, HUMAN CLL SAMPLES WITH LOWER DNMT3A EXPRESSION WERE MORE SENSITIVE TO NOTCH INHIBITION THAN THOSE WITH HIGHER DNMT3A EXPRESSION. ALTOGETHER, THESE RESULTS SUGGEST THAT DNMT3A DEPLETION INDUCES CLL THAT IS HIGHLY DEPENDENT ON ACTIVATION OF NOTCH AND MYC SIGNALING. SIGNIFICANCE: LOSS OF DNMT3A EXPRESSION IS A DRIVING EVENT IN CLL AND IS ASSOCIATED WITH AGGRESSIVE DISEASE, ACTIVATION OF NOTCH AND MYC SIGNALING, AND ENHANCED SENSITIVITY TO NOTCH INHIBITION.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                              
17 5871  31 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 3532  35 IMATINIB INDEPENDENT ABERRANT METHYLATION OF NOV/CCN3 IN CHRONIC MYELOGENOUS LEUKEMIA PATIENTS: A MECHANISM UPSTREAM OF BCR-ABL1 FUNCTION? BACKGROUND: THE NOV GENE PRODUCT, CCN3, HAS BEEN REPORTED IN A DIVERSE RANGE OF TUMORS TO SERVE AS A NEGATIVE GROWTH REGULATOR, WHILE ACTING AS A TUMOR SUPPRESSOR IN CHRONIC MYELOGENOUS LEUKEMIA (CML). HOWEVER, THE PRECISE MECHANISM OF ITS SILENCING IN CML IS POORLY UNDERSTOOD. IN THE CURRENT STUDY, WE AIMED TO QUERY IF THE GENE REGULATION OF CCN3 IS MEDIATED BY THE PROMOTER METHYLATION IN THE PATIENTS WITH CML. IN ADDITION, TO CLARIFY WHETHER THE EPIGENETIC SILENCING IS AFFECTED BY BCR-ABL1 INHIBITION, WE ASSESSED THE METHYLATION STATUS IN THE PATIENTS AT DIFFERENT TIME INTERVALS FOLLOWING THE TYROSINE KINASE INHIBITION USING IMATINIB THERAPY, AS THE FIRST-LINE TREATMENT FOR THIS TYPE OF LEUKEMIA. METHODS: TO ADDRESS THIS ISSUE, WE APPLIED BISULFITE-SEQUENCING TECHNIQUE AS A HIGH-RESOLUTION METHOD TO STUDY THE REGULATORY SEGMENT OF THE CCN3 GENE. THE RESULTS WERE ANALYZED IN NEWLY DIAGNOSED CML PATIENTS AS WELL AS FOLLOWING IMATINIB THERAPY. WE ALSO EVALUATED THE CORRELATION OF CCN3 PROMOTER METHYLATION WITH BCR-ABL1 LEVELS. RESULTS: OUR FINDINGS REVEALED THAT THE METHYLATION OCCURS FREQUENTLY IN THE PROMOTER REGION OF CML PATIENTS SHOWING A SIGNIFICANT INCREASE OF THE METHYLATED PERCENTAGE AT THE CPG SITES COMPARED TO NORMAL INDIVIDUALS. INTERESTINGLY, THIS HYPERMETHYLATION WAS INDICATED TO BE INDEPENDENT OF BCR-ABL1 TITERS IN BOTH GROUPS, WHICH MIGHT SUGGEST A MECHANISM BEYOND THE BCR-ABL1 FUNCTION. CONCLUSION: DESPITE SUGGESTING THAT THE CCN3 HYPERMETHYLATION ACTS AS A MOLECULAR MECHANISM INDEPENDENT OF BCR-ABL1 FUNCTION IN CML PATIENTS, THIS SCENARIO REQUIRES FURTHER VALIDATION BY COMPLEMENTARY EXPERIMENTS. IN THE CASE OF ACTING UPSTREAM OF BCR-ABL1 SIGNALING, THE METHYLATION MARKER CAN PROVIDE EARLY DETECTION AND A NOVEL PLATFORM FOR TARGETED EPIGENETIC MODIFIERS FOR EFFICIENT TREATMENT IN IMATINIB RESISTANT PATIENTS.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                               
19 4727  33 NOTABLE ROLES OF EZH2 AND DNMT1 IN EPIGENETIC DORMANCY OF THE SHP1 GENE DURING THE PROGRESSION OF CHRONIC MYELOID LEUKAEMIA. TUMOR DEVELOPMENT IS ASSOCIATED WITH THE METHYLATION OF CYTOSINE-GUANINE (CPG) ISLANDS. THE OCCURRENCE OF METHYLATION REQUIRES SEVERAL FACTORS, SUCH AS DNA METHYLATION SYSTEMS AND POLYCOMB GROUP (PCG) PROTEINS. AT PRESENT, NOVEL DRUGS ARE NEEDED FOR THE TREATMENT OF CHRONIC MYELOID LEUKAEMIA (CML), PARTICULARLY CONSIDERING THE CURRENT PROGNOSIS OF CML. THE METHYLATION STATUS OF THE SRC HOMOLOGY 2 DOMAIN-CONTAINING TYROSINE PHOSPHATASE 1 (SHP1) GENE, A NEGATIVE REGULATOR OF SIGNAL TRANSDUCTION, HAS BEEN IDENTIFIED AS BEING ALTERED IN NUMEROUS HAEMATOLOGICAL MALIGNANCIES. DNA METHYLTRANSFERASE 1 (DNMT1) AND THE PCG PROTEIN COMPLEX MEMBER ENHANCER OF ZESTE HOMOLOG 2 (EZH2) PARTICIPATE IN A NUMBER OF GENE METHYLATION PROCESSES. THE PRESENT STUDY INVESTIGATED THE METHYLATION STATUS OF THE SHP1 GENE IN CML, AND EXAMINED THE ASSOCIATION BETWEEN DNMT1 AND EZH2 ACTIVITY AND THE SHP1 GENE METHYLATION STATUS TO DEVELOP NOVEL STRATEGIES FOR THE TREATMENT OF CML. THE RESULTS REVEALED THAT SHP1 GENE METHYLATION STATUS WAS ALTERED DURING THE PROGRESSION OF CML. THESE DATA INDICATED THAT SHP1 GENE METHYLATION IS ASSOCIATED WITH THE PROGRESSION OF THIS DISEASE. THE ASSOCIATIONS OF DNMT1 AND EZH2 ACTIVITIES WITH THE METHYLATION STATUS OF THE SHP1 GENE WERE ADDITIONALLY INVESTIGATED VIA CHROMATIN IMMUNOPRECIPITATION. DNMT1 AND EZH2 WERE REVEALED TO BE BOUND TO THE PROMOTER REGION OF THE SHP1 GENE, AND WERE INVOLVED IN THE PROCESS OF SHP1 METHYLATION. FURTHERMORE, DNMT1 AND EZH2 WERE ASSOCIATED WITH DISEASE PROGRESSION. THUS, THE FINDINGS OF THE PRESENT STUDY SUGGEST A NEW TARGET FOR THE TREATMENT OF CML, PARTICULARLY FOR FUTURE DRUG DEVELOPMENT.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
20 3475  31 IDENTIFICATION OF A STAT5 TARGET GENE, DPF3, PROVIDES NOVEL INSIGHTS IN CHRONIC LYMPHOCYTIC LEUKEMIA. STAT5 CONTROLS ESSENTIAL CELLULAR FUNCTIONS AND IS ENCODED BY TWO GENES, STAT5A AND STAT5B. TO PROVIDE INSIGHT TO THE MECHANISMS LINKING HEMATOLOGIC MALIGNANCY TO STAT5 ACTIVATION/REGULATION OF TARGET GENES, WE IDENTIFIED STAT5 TARGET GENES AND FOCUSED ON DPF3 GENE, WHICH ENCODES FOR AN EPIGENETIC FACTOR. DPF3 EXPRESSION WAS INDUCED UPON IL-3 STIMULATION IN BA/F3 CELLS, WHILE STRONG BINDING OF BOTH STAT5A AND STAT5B WAS DETECTED IN ITS PROMOTER. REDUCED EXPRESSION OF DPF3 WAS DETECTED IN BA/F3 CELLS WITH STAT5A AND STAT5B KNOCK-DOWN, SUGGESTING THAT THIS GENE IS POSITIVELY REGULATED BY STAT5, UPON IL-3 STIMULATION. FURTHERMORE, THIS GENE WAS SIGNIFICANTLY UP-REGULATED IN CLL PATIENTS, WHERE DPF3 GENE/PROTEIN UP-REGULATION AND STRONG STAT5 BINDING TO THE DPF3 PROMOTER, CORRELATED WITH INCREASED STAT5 ACTIVATION, MAINLY IN NON-MALIGNANT MYELOID CELLS (GRANULOCYTES). OUR FINDINGS PROVIDE INSIGHTS IN THE STAT5 DEPENDENT TRANSCRIPTIONAL REGULATION OF DPF3, AND DEMONSTRATE FOR THE FIRST TIME INCREASED STAT5 ACTIVATION IN GRANULOCYTES OF CLL PATIENTS. NOVEL ROUTES OF INVESTIGATION ARE OPENED TO FACILITATE THE UNDERSTANDING OF THE ROLE OF STAT5 ACTIVATION IN THE COMMUNICATION BETWEEN NON-MALIGNANT MYELOID AND MALIGNANT B-CELLS, AND THE FUNCTIONS OF STAT5 TARGET GENES NETWORKS IN CLL BIOLOGY.	2013