1 5703 166 SINGLE-CELL MULTIOMICS REVEAL THE SCALE OF MULTILAYERED ADAPTATIONS ENABLING CLL RELAPSE DURING VENETOCLAX THERAPY. VENETOCLAX (VEN) INHIBITS THE PROSURVIVAL PROTEIN BCL2 TO INDUCE APOPTOSIS AND IS A STANDARD THERAPY FOR CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), DELIVERING HIGH COMPLETE REMISSION RATES AND PROLONGED PROGRESSION-FREE SURVIVAL IN RELAPSED CLL BUT WITH EVENTUAL LOSS OF EFFICACY. A SPECTRUM OF SUBCLONAL GENETIC CHANGES ASSOCIATED WITH VEN RESISTANCE HAS NOW BEEN DESCRIBED. TO FULLY UNDERSTAND CLINICAL RESISTANCE TO VEN, WE COMBINED SINGLE-CELL SHORT- AND LONG-READ RNA-SEQUENCING TO REVEAL THE PREVIOUSLY UNAPPRECIATED SCALE OF GENETIC AND EPIGENETIC CHANGES UNDERPINNING ACQUIRED VEN RESISTANCE. THESE APPEAR TO BE MULTILAYERED. ONE LAYER COMPRISES CHANGES IN THE BCL2 FAMILY OF APOPTOSIS REGULATORS, ESPECIALLY THE PROSURVIVAL FAMILY MEMBERS. THIS INCLUDES PREVIOUSLY DESCRIBED MUTATIONS IN BCL2 AND AMPLIFICATION OF THE MCL1 GENE BUT IS HETEROGENEOUS ACROSS AND WITHIN INDIVIDUAL PATIENT LEUKEMIAS. CHANGES IN THE PROAPOPTOTIC GENES ARE NOTABLY UNCOMMON, EXCEPT FOR SINGLE CASES WITH SUBCLONAL LOSSES OF BAX OR NOXA. MUCH MORE PROMINENT WAS UNIVERSAL MCL1 GENE UPREGULATION. THIS WAS DRIVEN BY AN OVERLYING LAYER OF EMERGENT NF-KAPPAB (NUCLEAR FACTOR KAPPA B) ACTIVATION, WHICH PERSISTED IN CIRCULATING CELLS DURING VEN THERAPY. WE DISCOVERED THAT MCL1 COULD BE A DIRECT TRANSCRIPTIONAL TARGET OF NF-KAPPAB. BOTH THE SWITCH TO ALTERNATIVE PROSURVIVAL FACTORS AND NF-KAPPAB ACTIVATION LARGELY DISSIPATE FOLLOWING VEN DISCONTINUATION. OUR STUDIES REVEAL THE EXTENT OF PLASTICITY OF CLL CELLS IN THEIR ABILITY TO EVADE VEN-INDUCED APOPTOSIS. IMPORTANTLY, THESE FINDINGS PINPOINT NEW APPROACHES TO CIRCUMVENT VEN RESISTANCE AND PROVIDE A SPECIFIC BIOLOGICAL JUSTIFICATION FOR THE STRATEGY OF VEN DISCONTINUATION ONCE A MAXIMAL RESPONSE IS ACHIEVED RATHER THAN MAINTAINING LONG-TERM SELECTIVE PRESSURE WITH THE DRUG. 2022 2 1333 44 DEREGULATION AND EPIGENETIC MODIFICATION OF BCL2-FAMILY GENES CAUSE RESISTANCE TO VENETOCLAX IN HEMATOLOGIC MALIGNANCIES. THE BCL2 INHIBITOR VENETOCLAX HAS BEEN APPROVED TO TREAT DIFFERENT HEMATOLOGICAL MALIGNANCIES. BECAUSE THERE IS NO COMMON GENETIC ALTERATION CAUSING RESISTANCE TO VENETOCLAX IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) AND B-CELL LYMPHOMA, WE ASKED IF EPIGENETIC EVENTS MIGHT BE INVOLVED IN VENETOCLAX RESISTANCE. THEREFORE, WE EMPLOYED WHOLE-EXOME SEQUENCING, METHYLATED DNA IMMUNOPRECIPITATION SEQUENCING, AND GENOME-WIDE CLUSTERED REGULARLY INTERSPACED SHORT PALINDROMIC REPEATS (CRISPR)/CRISPR-ASSOCIATED PROTEIN 9 SCREENING TO INVESTIGATE VENETOCLAX RESISTANCE IN AGGRESSIVE LYMPHOMA AND HIGH-RISK CLL PATIENTS. WE IDENTIFIED A REGULATORY CPG ISLAND WITHIN THE PUMA PROMOTER THAT IS METHYLATED UPON VENETOCLAX TREATMENT, MEDIATING PUMA DOWNREGULATION ON TRANSCRIPT AND PROTEIN LEVEL. PUMA EXPRESSION AND SENSITIVITY TOWARD VENETOCLAX CAN BE RESTORED BY INHIBITION OF METHYLTRANSFERASES. WE CAN DEMONSTRATE THAT LOSS OF PUMA RESULTS IN METABOLIC REPROGRAMMING WITH HIGHER OXIDATIVE PHOSPHORYLATION AND ADENOSINE TRIPHOSPHATE PRODUCTION, RESEMBLING THE METABOLIC PHENOTYPE THAT IS SEEN UPON VENETOCLAX RESISTANCE. ALTHOUGH PUMA LOSS IS SPECIFIC FOR ACQUIRED VENETOCLAX RESISTANCE BUT NOT FOR ACQUIRED MCL1 RESISTANCE AND IS NOT SEEN IN CLL PATIENTS AFTER CHEMOTHERAPY-RESISTANCE, BAX IS ESSENTIAL FOR SENSITIVITY TOWARD BOTH VENETOCLAX AND MCL1 INHIBITION. AS WE FOUND LOSS OF BAX IN RICHTER'S SYNDROME PATIENTS AFTER VENETOCLAX FAILURE, WE DEFINED BAX-MEDIATED APOPTOSIS TO BE CRITICAL FOR DRUG RESISTANCE BUT NOT FOR DISEASE PROGRESSION OF CLL INTO AGGRESSIVE DIFFUSE LARGE B-CELL LYMPHOMA IN VIVO. A COMPOUND SCREEN REVEALED TRAIL-MEDIATED APOPTOSIS AS A TARGET TO OVERCOME BAX DEFICIENCY. FURTHERMORE, ANTIBODY OR CAR T CELLS ELIMINATED VENETOCLAX RESISTANT LYMPHOMA CELLS, PAVING A CLINICALLY APPLICABLE WAY TO OVERCOME VENETOCLAX RESISTANCE. 2022 3 3457 24 HYPOMETHYLATION OF INTERLEUKIN-6 (IL-6) GENE INCREASES THE RISK OF ESSENTIAL HYPERTENSION: A MATCHED CASE-CONTROL STUDY. ESSENTIAL HYPERTENSION (EH) IS A CHRONIC DISEASE WITH CLEAR EPIGENETIC COMPONENT. INFLAMMATION AND ENDOTHELIAL DYSFUNCTION HAVE A GREAT ROLE IN THE DEVELOPMENT OF PERSISTENT BLOOD PRESSURE ELEVATION. THE AIM OF THIS STUDY WAS TO EXPLORE AN ASSOCIATION BETWEEN EH AND DNA METHYLATION IN PRO-INFLAMMATION CYTOKINE GENE INTERLEUKIN-6 (IL-6) DURING THE INFLAMMATORY PROCESS. WE PERFORMED METHYLATION ANALYSIS OF PERIPHERAL BLOOD DNA USING BISULPHITE PYROSEQUENCING TECHNOLOGY BETWEEN 96 EH PATIENTS AND 96 AGE- AND GENDER-MATCHED HEALTHY CONTROLS. THE PRESENT RESULTS SHOWED THAT THREE CYTOSINE-PHOSPHATE-GUANINE (CPG) SITES OF IL-6 PROMOTER CPG ISLAND HAD DIFFERENT LOWER METHYLATION IN EH GROUP COMPARED WITH CONTROLS, BUT ONLY CPG2 (58.43+/-7.53 VERSUS 62.34+/-9.65, P=0.004) AND CPG3 (51.52+/-6.18 VERSUS 57.45+/-8.29, P<0.001) HAD STATISTICAL DIFFERENCE. LOGISTIC REGRESSION ANALYSIS FOUND CPG3 HYPOMETHYLATION WAS A RISK FACTOR OF EH (ODDS RATIO=1.111, ADJUSTED P=0.004). IN ADDITION, WE FOUND HYPERMETHYLATION OF CPG1 (64.84+/-7.06 VERSUS 61.84+/-8.61) AND CPG2 (62.04+/-7.40 VERSUS 59.30+/-9.57) IN MALE COMPARED WITH FEMALE. IN MALE, WE FOUND HYPOMETHYLATION OF CPG2 (60.41+/-7.74 VERSUS 64.28+/-6.36) AND CPG3 (53.70+/-8.62 VERSUS 57.78+/-7.87) OF SMOKER VERSUS NON-SMOKER AND HYPOMETHYLATION OF CPG2 (60.89+/-7.32 VERSUS 64.70+/-7.03) AND CPG3 (53.23+/-7.99 VERSUS 60.48+/-7.58) OF DRINKER VERSUS NON-DRINKER. FURTHERMORE, THE CPG2 AND CPG3 HAD A NEGATIVE CORRELATION WITH SYSTOLIC BLOOD PRESSURE AND DIASTOLIC BLOOD PRESSURE (P<0.05). RECEIVER OPERATING CHARACTERISTIC CURVE ANALYSIS SHOWED THAT CPG2 (AREA UNDER CURVE: 0.638, P=0.001) AND CPG3 (AREA UNDER CURVE: 0.704, P<0.001) HAD A DIAGNOSTIC VALUE TO PREDICT THE RISK OF EH. IN SUMMARY, OUR STUDY REVEALED HYPOMETHYLATION OF IL-6 WAS CORRELATED WITH THE RISK OF EH IN THE POPULATION ASSESSED AND WE FOUND THE DIFFERENCES OF IL-6 PROMOTER METHYLATION IN GENDER, SMOKING AND DRINKING. 2017 4 1107 32 COMBINING CYTOGENETIC AND EPIGENETIC APPROACHES IN CHRONIC LYMPHOCYTIC LEUKEMIA IMPROVES PROGNOSIS PREDICTION FOR PATIENTS WITH ISOLATED 13Q DELETION. BACKGROUND: BOTH DEFECTIVE DNA METHYLATION AND ACTIVE DNA DEMETHYLATION PROCESSES ARE EMERGING AS IMPORTANT RISK FACTORS IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). HOWEVER, ASSOCIATIONS BETWEEN 5-CYTOSINE EPIGENETIC MARKERS AND THE MOST FREQUENT CHROMOSOMAL ABNORMALITIES DETECTED IN CLL REMAIN TO BE ESTABLISHED. METHODS: CLL PATIENTS WERE RETROSPECTIVELY CLASSIFIED INTO A CYTOGENETIC LOW-RISK GROUP (ISOLATED 13Q DELETION), AN INTERMEDIATE-RISK GROUP (NORMAL KARYOTYPE OR TRISOMY 12), AND A HIGH-RISK GROUP (11Q DELETION, 17P DELETION, OR COMPLEX KARYOTYPE [>/= 3 BREAKPOINTS]). THE TWO 5-CYTOSINE DERIVATIVES, 5-METHYLCYTOSINE (5-MCYT) AND 5-HYDROXYMETHYLCYTOSINE (5-HMCYT), WERE TESTED BY ELISA (N = 60), WHILE REAL-TIME QUANTITATIVE PCR WAS USED FOR DETERMINING TRANSCRIPTIONAL EXPRESSION LEVELS OF DNMT AND TET (N = 24). RESULTS: BY USING GLOBAL DNA METHYLATION/DEMETHYLATION LEVELS, IN THE LOW-RISK DISEASE GROUP, TWO SUBGROUPS WITH SIGNIFICANTLY DIFFERENT CLINICAL OUTCOMES HAVE BEEN IDENTIFIED (MEDIAN TREATMENT-FREE SURVIVAL [TFS] 45 VERSUS > 120 MONTHS FOR 5-MCYT, P = 0.0008, AND 63 VERSUS > 120 MONTHS FOR 5-HMCYT, P = 0.04). A DEFECTIVE 5-MCYT STATUS WAS FURTHER ASSOCIATED WITH A HIGHER PERCENTAGE OF 13Q DELETED NUCLEI (> 80%), THUS SUGGESTING AN ACQUIRED PROCESS. WHEN CONSIDERING THE CYTOGENETIC INTERMEDIATE/HIGH-RISK DISEASE GROUPS, AN ASSOCIATION OF 5-MCYT STATUS WITH LYMPHOCYTOSIS (P = 0.0008) AND THE LYMPHOCYTE DOUBLING TIME (P = 0.04) BUT NOT WITH TFS WAS OBSERVED, AS WELL AS A REDUCTION OF DNMT3A, TET1, AND TET2 TRANSCRIPTS. CONCLUSIONS: COMBINING CYTOGENETIC STUDIES WITH 5-MCYT ASSESSMENT ADDS ACCURACY TO CLL PATIENTS' PROGNOSES AND PARTICULARLY FOR THOSE WITH 13Q DELETION AS A SOLE CYTOGENETIC ABNORMALITY. 2017 5 2087 36 EPIGENETIC DYSREGULATION OF ID4 PREDICTS DISEASE PROGRESSION AND TREATMENT OUTCOME IN MYELOID MALIGNANCIES. PROMOTER HYPERMETHYLATION-MEDIATED INACTIVATION OF ID4 PLAYS A CRUCIAL ROLE IN THE DEVELOPMENT OF SOLID TUMOURS. THIS STUDY AIMED TO INVESTIGATE ID4 METHYLATION AND ITS CLINICAL RELEVANCE IN MYELOID MALIGNANCIES. ID4 HYPERMETHYLATION WAS ASSOCIATED WITH HIGHER IPSS SCORES, BUT WAS NOT AN INDEPENDENT PROGNOSTIC BIOMARKER AFFECTING OVERALL SURVIVAL (OS) IN MYELODYSPLASTIC SYNDROME (MDS). HOWEVER, ID4 HYPERMETHYLATION CORRELATED WITH SHORTER OS AND LEUKAEMIA-FREE SURVIVAL (LFS) TIME AND ACTED AS AN INDEPENDENT RISK FACTOR AFFECTING OS IN ACUTE MYELOID LEUKAEMIA (AML). MOREOVER, ID4 METHYLATION WAS SIGNIFICANTLY DECREASED IN THE FOLLOW-UP PAIRED AML PATIENTS WHO ACHIEVED COMPLETE REMISSION (CR) AFTER INDUCTION THERAPY. IMPORTANTLY, ID4 METHYLATION WAS INCREASED DURING MDS PROGRESSION TO AML AND CHRONIC PHASE (CP) PROGRESSION TO BLAST CRISIS (BC) IN CHRONIC MYELOID LEUKAEMIA (CML). EPIGENETIC STUDIES SHOWED THAT ID4 METHYLATION MIGHT BE ONE OF THE MECHANISMS SILENCING ID4 EXPRESSION IN MYELOID LEUKAEMIA. FUNCTIONAL STUDIES IN VITRO SHOWED THAT RESTORATION OF ID4 EXPRESSION COULD INHIBIT CELL PROLIFERATION AND PROMOTE APOPTOSIS IN BOTH K562 AND HL60 CELLS. THESE FINDINGS INDICATE THAT ID4 ACTS AS A TUMOUR SUPPRESSOR IN MYELOID MALIGNANCIES, AND ID4 METHYLATION IS A POTENTIAL BIOMARKER IN PREDICTING DISEASE PROGRESSION AND TREATMENT OUTCOME. 2017 6 2678 26 EVALUATION OF A PROGNOSTIC EPIGENETIC CLASSIFICATION SYSTEM IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS. BACKGROUND: METHYLATION AT 5 CPG SITES WAS PREVIOUSLY SHOWN TO CLASSIFY CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) INTO 3 PROGNOSTIC SUBGROUPS. HERE, WE AIMED TO VALIDATE THE MARKER SET IN AN ADDITIONAL COHORT AND TO EVALUATE ITS CLINICAL UTILITY FOR CLL PATIENT STRATIFICATION. METHODS: WE EVALUATED THIS EPIGENETIC MARKER SET IN 79 GERMAN PATIENTS USING BISULFITE TREATMENT FOLLOWED BY PYROSEQUENCING AND CLASSIFICATION USING A SUPPORT VECTOR MACHINE-LEARNING TOOL. RESULTS: THE N-CLL, I-CLL, AND M-CLL CLASSIFICATION WAS DETECTED IN 28 (35%), 10 (13%), AND 41 (51%) PATIENTS, RESPECTIVELY. EPIGENETIC GROUPING WAS ASSOCIATED WITH IGHV MUTATIONAL STATUS (P = 2 X 10(-12)), ISOLATED DEL13Q (P = 9 X 10(-6)), DEL17P (P = .015), COMPLEX KARYOTYPE (P = .005), VH-USAGE, AND CLINICAL OUTCOME AS TIME TO FIRST TREATMENT (P = 1.4 X 10(-12)) AND OVERALL SURVIVAL (P = .003). MULTIVARIATE COX REGRESSION ANALYSIS IDENTIFIED N-CLL AS A FACTOR FOR EARLIER TREATMENT HAZARD RATIO (HR), 6.3 (95% CONFIDENCE INTERVAL [CI] 2.4-16.4; P = .0002) COMPARED TO IGHV MUTATIONAL STATUS (HR 4.6, 95% CI 1.9-11.3, P = .0008). IN ADDITION, WHEN COMPARING THE PROGNOSTIC VALUE OF THE EPIGENETIC CLASSIFICATION SYSTEM WITH THE IGHV CLASSIFICATION, EPIGENETIC GROUPING PERFORMED BETTER COMPARED TO IGHV MUTATIONAL STATUS USING KAPLAN-MEIER ESTIMATION AND ALLOWED THE IDENTIFICATION OF A THIRD, INTERMEDIATE (I-CLL) GROUP. THUS, OUR STUDY CONFIRMED THE PROGNOSTIC VALUE OF THE EPIGENETIC MARKER SET FOR PATIENT STRATIFICATION IN ROUTINE CLINICAL DIAGNOSTICS. 2022 7 5243 28 PROGNOSTIC IMPACT OF EPIGENETIC CLASSIFICATION IN CHRONIC LYMPHOCYTIC LEUKEMIA: THE CASE OF SUBSET #2. BASED ON THE METHYLATION STATUS OF 5 SINGLE CPG SITES, A NOVEL EPIGENETIC CLASSIFICATION OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) WAS RECENTLY PROPOSED, CLASSIFYING CLL PATIENTS INTO 3 CLINICO-BIOLOGICAL SUBGROUPS WITH DIFFERENT OUTCOME, TERMED MEMORY LIKE CLL (M-CLL), NAIVE LIKE CLL (N-CLL), AND A THIRD INTERMEDIATE CLL SUBGROUP (I-CLL). WHILE M-CLL AND N-CLL PATIENTS AT LARGE CORRESPONDED TO PATIENTS CARRYING MUTATED AND UNMUTATED IGHV GENES, RESPECTIVELY, LIMITED INFORMATION EXISTS REGARDING THE LESS DEFINED I-CLL GROUP. USING PYROSEQUENCING, WE INVESTIGATED THE PROGNOSTIC IMPACT OF THE PROPOSED 5 CPG SIGNATURE IN A WELL-CHARACTERIZED CLL COHORT (135 CASES), INCLUDING IGHV-MUTATED AND UNMUTATED PATIENTS AS WELL AS CLINICALLY AGGRESSIVE STEREOTYPED SUBSET #2 PATIENTS. OVERALL, WE CONFIRMED THE SIGNATURE'S ASSOCIATION WITH ESTABLISHED PROGNOSTIC MARKERS. MOREOVER, IN THE PRESENCE OF THE IGHV MUTATIONAL STATUS, THE EPIGENETIC SIGNATURE REMAINED INDEPENDENTLY ASSOCIATED WITH BOTH TIME-TO-FIRST-TREATMENT AND OVERALL SURVIVAL IN MULTIVARIATE ANALYSES. AS A PRIME FINDING, WE OBSERVED THAT SUBSET #2 PATIENTS WERE PREDOMINANTLY CLASSIFIED AS I-CLL, PROBABLY REFLECTING THEIR BORDERLINE IGHV MUTATIONAL STATUS (97-99% GERMLINE IDENTITY), THOUGH HAVING A SIMILARLY POOR PROGNOSIS AS N-CLL PATIENTS. IN SUMMARY, WE VALIDATED THE EPIGENETIC CLASSIFIER AS AN INDEPENDENT FACTOR IN CLL PROGNOSTICATION AND PROVIDE FURTHER EVIDENCE THAT SUBSET #2 IS A MEMBER OF THE I-CLL GROUP, HENCE SUPPORTING THE EXISTENCE OF A THIRD, INTERMEDIATE EPIGENETIC SUBGROUP. 2016 8 6460 32 TIME TO RELAPSE IN CHRONIC LYMPHOCYTIC LEUKEMIA AND DNA-METHYLATION-BASED BIOLOGICAL AGE. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS A MATURE B CELL NEOPLASM WITH A PREDILECTION FOR OLDER INDIVIDUALS. WHILE PREVIOUS STUDIES HAVE IDENTIFIED EPIGENETIC SIGNATURES ASSOCIATED WITH CLL, WHETHER AGE-RELATED DNA METHYLATION CHANGES MODULATE CLL RELAPSE REMAINS ELUSIVE. IN THIS STUDY, WE EXAMINED THE ASSOCIATION BETWEEN EPIGENETIC AGE ACCELERATION AND TIME TO CLL RELAPSE IN A PUBLICLY AVAILABLE DATASET. DNA METHYLATION PROFILING OF 35 CLL PATIENTS PRIOR TO INITIATING CHEMOIMMUNOTHERAPY WAS PERFORMED USING THE INFINIUM HUMANMETHYLATION450 BEADCHIP. FOUR EPIGENETIC AGE ACCELERATION METRICS (INTRINSIC EPIGENETIC AGE ACCELERATION [IEAA], EXTRINSIC EPIGENETIC AGE ACCELERATION [EEAA], PHENOAGE ACCELERATION [PHENOAA], AND GRIMAGE ACCELERATION [GRIMAA]) WERE ESTIMATED FROM BLOOD DNA METHYLATION LEVELS. LINEAR, QUANTILE, AND LOGISTIC REGRESSION AND RECEIVER OPERATING CHARACTERISTIC CURVE ANALYSES WERE CONDUCTED TO ASSESS THE ASSOCIATION BETWEEN EACH EPIGENETIC AGE METRIC AND TIME TO CLL RELAPSE. EEAA (P = 0.011) AND PHENOAA (P = 0.046) WERE NEGATIVELY AND GRIMAA (P = 0.040) WAS POSITIVELY ASSOCIATED WITH TIME TO CLL RELAPSE. SIMULTANEOUS ASSESSMENT OF EEAA AND GRIMAA IN MALE PATIENTS DISTINGUISHED PATIENTS WHO RELAPSED EARLY FROM PATIENTS WHO RELAPSED LATER (P = 0.039). NO ASSOCIATIONS WERE OBSERVED WITH IEAA. THESE FINDINGS SUGGEST EPIGENETIC AGE ACCELERATION PRIOR TO CHEMOIMMUNOTHERAPY INITIATION IS ASSOCIATED WITH TIME TO CLL RELAPSE. OUR RESULTS PROVIDE NOVEL INSIGHT INTO THE ASSOCIATION BETWEEN AGE-RELATED DNA METHYLATION CHANGES AND CLL RELAPSE AND MAY SERVE HAS BIOMARKERS FOR TREATMENT RELAPSE, AND POTENTIALLY, TREATMENT SELECTION. 2023 9 3460 25 HYPOMETHYLATION OF THE IL8 PROMOTER IN NASAL EPITHELIAL CELLS OF PATIENTS WITH CHRONIC RHINOSINUSITIS WITH NASAL POLYPS. BACKGROUND: IL-8 IS AN IMPORTANT CHEMOKINE IMPLICATED IN THE PATHOGENESIS OF CHRONIC RHINOSINUSITIS (CRS), BUT LITTLE IS KNOWN ABOUT EPIGENETIC REGULATION OF IL8 IN THE PATHOGENESIS OF CRS. OBJECTIVE: WE SOUGHT TO INVESTIGATE THE RELATIONSHIP BETWEEN THE DNA METHYLATION LEVEL IN THE IL8 PROXIMAL PROMOTER AND CRS IN HAN CHINESE SUBJECTS. METHODS: PATIENTS WITH CHRONIC RHINOSINUSITIS WITH NASAL POLYPS (CRSWNP; N = 187), PATIENTS WITH CHRONIC RHINOSINUSITIS WITHOUT NASAL POLYPS (CRSSNP; N = 89), AND CONTROL SUBJECTS (N = 57) WERE ENROLLED IN 2 INDEPENDENT COHORTS. PURIFIED HUMAN NASAL EPITHELIAL CELLS FROM EACH PARTICIPANT WERE ASSESSED FOR PERCENTAGE DNA METHYLATION OF CPG SITES IN THE IL8 PROXIMAL PROMOTER BY USING BISULFITE PYROSEQUENCING AND FOR FUNCTIONAL ASPECTS OF METHYLATION STATUS BY USING IN VITRO ASSAYS. RESULTS: DNA METHYLATION OF CPG SITES 1, 2, AND 3, RESPECTIVELY, IN THE IL8 PROXIMAL PROMOTER WAS SIGNIFICANTLY DECREASED IN HUMAN NASAL EPITHELIAL CELLS OF PATIENTS WITH CRSWNP COMPARED WITH THAT IN PATIENTS WITH CRSSNP (P < .001) AND CONTROL SUBJECTS (P < .001). PERCENTAGE OF DNA METHYLATION OF THE CPG3 SITE WAS CORRELATED NEGATIVELY WITH BOTH TISSUE EOSINOPHILIC CATIONIC PROTEIN (P < .01) AND MYELOPEROXIDASE (P < .05) LEVELS. IL-1BETA (P < .001) AND TNF-ALPHA (P < .01) SIGNIFICANTLY INCREASED IL8 EXPRESSION ACCOMPANIED BY A REDUCTION IN METHYLATION AT THE CPG3 SITE (P < .001). ELECTROPHORETIC MOBILITY SHIFT ASSAYS DEMONSTRATED THAT METHYLATION STATUS OF CPG3 CHANGED THE BINDING OF OCTAMER-BINDING TRANSCRIPTION FACTOR 1 AND NUCLEAR FACTOR KAPPAB. CONCLUSION: DECREASED DNA METHYLATION OF PARTICULARLY CPG SITES IN THE IL8 PROXIMAL PROMOTER MIGHT PLAY A ROLE IN THE PATHOGENESIS OF CRSWNP. 2019 10 1581 32 DNA METHYLATION PROFILES IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS TREATED WITH CHEMOIMMUNOTHERAPY. BACKGROUND: IN ORDER TO GAIN INSIGHT INTO THE CONTRIBUTION OF DNA METHYLATION TO DISEASE PROGRESSION OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), USING 450K ILLUMINA ARRAYS, WE DETERMINED THE DNA METHYLATION PROFILES IN PAIRED PRE-TREATMENT/RELAPSE SAMPLES FROM 34 CLL PATIENTS TREATED WITH CHEMOIMMUNOTHERAPY, MOSTLY (N = 31) WITH THE FLUDARABINE-CYCLOPHOSPHAMIDE-RITUXIMAB (FCR) REGIMEN. RESULTS: THE EXTENT OF IDENTIFIED CHANGES IN CLL CELLS VERSUS MEMORY B CELLS FROM HEALTHY DONORS WAS TERMED "EPIGENETIC BURDEN" (EB) WHEREAS THE NUMBER OF CHANGES BETWEEN THE PRE-TREATMENT VERSUS THE RELAPSE SAMPLE WAS TERMED "RELAPSE CHANGES" (RC). SIGNIFICANT (P < 0.05) ASSOCIATIONS WERE IDENTIFIED BETWEEN (I) HIGH EB AND SHORT TIME-TO-FIRST-TREATMENT (TTFT); AND, (II) FEW RCS AND SHORT TIME-TO-RELAPSE. BOTH THE EB AND THE RC CLUSTERED IN SPECIFIC GENOMIC REGIONS AND CHROMATIN STATES, INCLUDING REGULATORY REGIONS CONTAINING BINDING SITES OF TRANSCRIPTION FACTORS IMPLICATED IN B CELL AND CLL BIOLOGY. CONCLUSIONS: OVERALL, WE SHOW THAT DNA METHYLATION IN CLL FOLLOWS DIFFERENT DYNAMICS IN RESPONSE TO CHEMOIMMUNOTHERAPY. THESE EPIGENETIC ALTERATIONS WERE LINKED WITH SPECIFIC CLINICAL AND BIOLOGICAL FEATURES. 2019 11 157 29 ABERRANT METHYLATION OF TUMOUR SUPPRESSOR GENE ADAM12 IN CHRONIC LYMPOCYTIC LEUKEMIA PATIENTS: APPLICATION OF METHYLATION SPECIFIC-PCR TECHNIQUE. OBJECTIVE: CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS A COMMON LEUKEMIA AMONG CAUCASIANS BUT RARE IN ASIANS POPULATION. WE POSTULATED THAT ABERRANT METHYLATION EITHER HYPERMETHYLATION OR PARTIAL METHYLATION MIGHT BE ONE OF THE SILENCING MECHANISMS THAT INACTIVATES THE TUMOUR SUPPRESSOR GENES IN CLL. THIS STUDY AIMED TO COMPARE THE METHYLATION STATUS OF TUMOUR SUPPRESSOR GENE, ADAM12, AMONG CLL PATIENTS AND NORMAL INDIVIDUALS. WE ALSO EVALUATED THE ASSOCIATION BETWEEN METHYLATION OF ADAM12 AND CLINICAL AND DEMOGRAPHIC CHARACTERISTICS OF THE PARTICIPANTS. METHODS: A TOTAL OF 25 CLL PATIENTS AND 25 NORMAL INDIVIDUALS WERE RECRUITED IN THIS STUDY. THE METHYLATION STATUS OF ADAM12 WAS DETERMINED USING METHYLATION-SPECIFIC PCR (MSP); WHEREAS, DNA SEQUENCING METHOD WAS APPLIED FOR VALIDATION OF THE MSP RESULTS. RESULTS: AMONG CLL PATIENTS, 12 (48%) WERE PARTIALLY METHYLATED AND 13 (52%) WERE UNMETHYLATED. MEANWHILE, 5 (20%) AND 20 (80.6%) OF HEALTHY INDIVIDUALS WERE PARTIALLY METHYLATED AND UNMETHYLATED, RESPECTIVELY. THERE WAS A STATISTICALLY SIGNIFICANT ASSOCIATION BETWEEN THE STATUS OF METHYLATION AT ADAM12 AND THE PRESENCE OF CLL (P=0.037). CONCLUSION: THE ABERRANT METHYLATION OF ADAM12 FOUND IN THIS STUDY USING MSP ASSAY MAY PROVIDE NEW EXPOSURE TO CLL THAT MAY IMPROVE THE GAPS INVOLVED IN GENETIC EPIGENETIC STUDY IN CLL. 2021 12 1132 32 COMPREHENSIVE DNA METHYLATION ANALYSIS USING A METHYL-CPG-BINDING DOMAIN CAPTURE-BASED METHOD IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS. THE ROLE OF LONG NONCODING RNAS (LNCRNAS) IN CANCER IS COMING TO THE FOREFRONT DUE TO GROWING INTEREST IN UNDERSTANDING THEIR MECHANISTIC FUNCTIONS DURING CANCER DEVELOPMENT AND PROGRESSION. DESPITE THIS, THE GLOBAL EPIGENETIC REGULATION OF LNCRNAS AND REPETITIVE SEQUENCES IN CANCER HAS NOT BEEN WELL INVESTIGATED, PARTICULARLY IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). THIS STUDY FOCUSES ON A UNIQUE APPROACH: THE IMMUNOPRECIPITATION-BASED CAPTURE OF DOUBLE-STRANDED, METHYLATED DNA FRAGMENTS USING METHYL-BINDING DOMAIN (MBD) PROTEINS, FOLLOWED BY NEXT-GENERATION SEQUENCING (MBD-SEQ). CLL PATIENT SAMPLES BELONGING TO TWO PROGNOSTIC SUBGROUPS (5 IGVH MUTATED SAMPLES + 5 IGVH UNMUTATED SAMPLES) WERE USED IN THIS STUDY. ANALYSIS REVEALED 5,800 HYPERMETHYLATED AND 12,570 HYPOMETHYLATED CLL-SPECIFIC DIFFERENTIALLY METHYLATED GENES (CLLDMGS) COMPARED TO NORMAL HEALTHY CONTROLS. IMPORTANTLY, THESE RESULTS IDENTIFIED SEVERAL CLL-SPECIFIC, DIFFERENTIALLY METHYLATED LNCRNAS, REPETITIVE ELEMENTS, AND PROTEIN-CODING GENES WITH POTENTIAL PROGNOSTIC VALUE. THIS WORK OUTLINES A DETAILED PROTOCOL FOR AN MBD-SEQ AND BIOINFORMATICS PIPELINE DEVELOPED FOR THE COMPREHENSIVE ANALYSIS OF GLOBAL METHYLATION PROFILES IN HIGHLY CPG-RICH REGIONS USING CLL PATIENT SAMPLES. FINALLY, A PROTEIN-CODING GENE AND AN LNCRNA WERE VALIDATED USING PYROSEQUENCING, WHICH IS A HIGHLY QUANTITATIVE METHOD TO ANALYZE CPG METHYLATION LEVELS TO FURTHER CORROBORATE THE FINDINGS FROM THE MBD-SEQ PROTOCOL. 2017 13 1495 28 DNA HYPERMETHYLATION OF CELL CYCLE (P15 AND P16) AND APOPTOTIC (P14, P53, DAPK AND TMS1) GENES IN PERIPHERAL BLOOD OF LEUKEMIA PATIENTS. ABERRANT DNA METHYLATION OF TUMOR SUPPRESSOR GENES HAS BEEN REPORTED IN ALL MAJOR TYPES OF LEUKEMIA WITH POTENTIAL INVOLVEMENT IN THE INACTIVATION OF REGULATORY CELL CYCLE AND APOPTOSIS GENES. HOWEVER, MOST OF THE PREVIOUS REPORTS DID NOT SHOW THE EXTENT OF CONCURRENT METHYLATION OF MULTIPLE GENES IN THE FOUR LEUKEMIA TYPES. HERE, WE ANALYZED SIX KEY GENES (P14, P15, P16, P53, DAPK AND TMS1) FOR DNA METHYLATION USING METHYLATION SPECIFIC PCR TO ANALYZE PERIPHERAL BLOOD OF 78 LEUKEMIA PATIENTS (24 CML, 25 CLL, 12 AML, AND 17 ALL) AND 24 HEALTHY VOLUNTEERS. IN CML, METHYLATION WAS DETECTED FOR P15 (11%), P16 (9%), P53 (23%) AND DAPK (23%), IN CLL, P14 (25%), P15 (19%), P16 (12%), P53 (17%) AND DAPK (36%), IN AML, P14 (8%), P15 (45%), P53 (9%) AND DAPK (17%) AND IN ALL, P15 (14%), P16 (8%), AND P53 (8%). THIS STUDY HIGHLIGHTED AN ESSENTIAL ROLE OF DAPK METHYLATION IN CHRONIC LEUKEMIA IN CONTRAST TO P15 METHYLATION IN THE ACUTE CASES, WHEREAS TMS1 HYPERMETHYLATION WAS ABSENT IN ALL CASES. FURTHERMORE, HYPERMETHYLATION OF MULTIPLE GENES PER PATIENT WAS OBSERVED, WITH OBVIOUS SELECTIVENESS IN THE 9P21 CHROMOSOMAL REGION GENES (P14, P15 AND P16). INTERESTINGLY, METHYLATION OF P15 INCREASED THE RISK OF METHYLATION IN P53, AND VICE VERSA, BY FIVE FOLDS (P=0.03) INDICATING POSSIBLE SYNERGISTIC EPIGENETIC DISRUPTION OF DIFFERENT PHASES OF THE CELL CYCLE OR BETWEEN THE CELL CYCLE AND APOPTOSIS. THE INVESTIGATION OF MULTIPLE RELATIONSHIPS BETWEEN METHYLATED GENES MIGHT SHED LIGHT ON TUMOR SPECIFIC INACTIVATION OF THE CELL CYCLE AND APOPTOTIC PATHWAYS. 2014 14 1102 32 COMBINED CHEMOSENSITIVITY AND CHROMATIN PROFILING PRIORITIZES DRUG COMBINATIONS IN CLL. THE BRUTON TYROSINE KINASE (BTK) INHIBITOR IBRUTINIB HAS SUBSTANTIALLY IMPROVED THERAPEUTIC OPTIONS FOR CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). ALTHOUGH IBRUTINIB IS NOT CURATIVE, IT HAS A PROFOUND EFFECT ON CLL CELLS AND MAY CREATE NEW PHARMACOLOGICALLY EXPLOITABLE VULNERABILITIES. TO IDENTIFY SUCH VULNERABILITIES, WE DEVELOPED A SYSTEMATIC APPROACH THAT COMBINES EPIGENOME PROFILING (CHARTING THE GENE-REGULATORY BASIS OF CELL STATE) WITH SINGLE-CELL CHEMOSENSITIVITY PROFILING (QUANTIFYING CELL-TYPE-SPECIFIC DRUG RESPONSE) AND BIOINFORMATIC DATA INTEGRATION. BY APPLYING OUR METHOD TO A COHORT OF MATCHED PATIENT SAMPLES COLLECTED BEFORE AND DURING IBRUTINIB THERAPY, WE IDENTIFIED CHARACTERISTIC IBRUTINIB-INDUCED CHANGES THAT PROVIDE A STARTING POINT FOR THE RATIONAL DESIGN OF IBRUTINIB COMBINATION THERAPIES. SPECIFICALLY, WE OBSERVED AND VALIDATED PREFERENTIAL SENSITIVITY TO PROTEASOME, PLK1, AND MTOR INHIBITORS DURING IBRUTINIB TREATMENT. MORE GENERALLY, OUR STUDY ESTABLISHES A BROADLY APPLICABLE METHOD FOR INVESTIGATING TREATMENT-SPECIFIC VULNERABILITIES BY INTEGRATING THE COMPLEMENTARY PERSPECTIVES OF EPIGENETIC CELL STATES AND PHENOTYPIC DRUG RESPONSES IN PRIMARY PATIENT SAMPLES. 2019 15 163 34 ABL1 METHYLATION IS A DISTINCT MOLECULAR EVENT ASSOCIATED WITH CLONAL EVOLUTION OF CHRONIC MYELOID LEUKEMIA. METHYLATION OF THE PROXIMAL PROMOTER OF THE ABL1 ONCOGENE IS A COMMON EPIGENETIC ALTERATION ASSOCIATED WITH CLINICAL PROGRESSION OF CHRONIC MYELOID LEUKEMIA (CML). IN THIS STUDY WE QUERIED WHETHER BOTH THE PH'-ASSOCIATED AND NORMAL ABL1 ALLELES UNDERGO METHYLATION; WHAT MAY BE THE PROPORTION OF HEMATOPOIETIC PROGENITORS BEARING METHYLATED ABL1 PROMOTERS IN CHRONIC VERSUS ACUTE PHASE DISEASE; WHETHER METHYLATION AFFECTS THE PROMOTER UNIFORMLY OR IN PATCHES WITH DISCRETE CLINICAL RELEVANCE; AND, FINALLY, WHETHER METHYLATION OF ABL1 REFLECTS A GENERALIZED PROCESS OR IS GENE-SPECIFIC. TO ADDRESS THESE ISSUES, WE ADAPTED THE TECHNIQUES OF METHYLATION-SPECIFIC PCR AND BISULFITE-SEQUENCING TO STUDY THE REGULATORY REGIONS OF ABL1 AND OTHER GENES WITH A ROLE IN DNA REPAIR OR GENOTOXIC STRESS RESPONSE. IN CELL LINES ESTABLISHED FROM CML BLAST CRISIS, WHICH ONLY CARRY A SINGLE ABL1 ALLELE NESTED WITHIN THE BCR-ABL FUSION GENE, ABL1 PROMOTERS WERE UNIVERSALLY METHYLATED. BY CONTRAST, IN CLINICAL SAMPLES FROM PATIENTS AT ADVANCED STAGES OF DISEASE, BOTH METHYLATED AND UNMETHYLATED PROMOTER ALLELES WERE DETECTABLE. TO DISTINGUISH BETWEEN ALLELE-SPECIFIC METHYLATION AND A MIXED CELL POPULATION PATTERN, WE STUDIED THE METHYLATION STATUS OF ABL1 IN COLONIES DERIVED FROM SINGLE HEMATOPOIETIC PROGENITORS. OUR RESULTS SHOWED THAT BOTH METHYLATED AND UNMETHYLATED PROMOTER ALLELES COEXISTED IN THE SAME COLONY. FURTHERMORE, ABL1 METHYLATION WAS NOTED IN THE VAST MAJORITY OF COLONIES FROM BLAST CRISIS, BUT NOT CHRONIC-PHASE CML. BOTH CELL LINES AND CLINICAL SAMPLES FROM ACUTE-PHASE CML SHOWED NEARLY UNIFORM HYPERMETHYLATION ALONG THE PROMOTER REGION. FINALLY, WE SHOWED THAT ABL1 METHYLATION DOES NOT REFLECT A GENERALIZED PROCESS AND MAY BE UNIQUE AMONG DNA REPAIR/GENOTOXIC STRESS RESPONSE GENES. OUR DATA SUGGEST THAT SPECIFIC METHYLATION OF THE PH'-ASSOCIATED ABL1 ALLELE ACCOMPANIES CLONAL EVOLUTION IN CML. 1999 16 6366 31 THE ROLE OF METHYLATION IN CML. METHYLATION OF THE PROXIMAL PROMOTER OF THE ABL1 ONCOGENE IS COMMON EPIGENETIC ALTERATION ASSOCIATED WITH CLINICAL PROGRESSION OF CHRONIC MYELOID LEUKEMIA (CML). IN PRESENTED STUDY WE QUERIED WHETHER BOTH THE PH'-ASSOCIATED AND NORMAL ABL1 ALLELES UNDERGO METHYLATION; WHAT MAY BE THE PROPORTION OF HEMATOPOIETIC PROGENITORS BEARING METHYLATED ABL1 PROMOTERS IN CHRONIC VERSUS ACUTE PHASE DISEASE; WHETHER METHYLATION AFFECTS THE PROMOTER UNIFORMLY OR IN PATCHES WITH DISCRETE CLINICAL RELEVANCE; AND, FINALLY WHETHER METHYLATION OF ABL1 REFLECTS A GENERALIZED PROCESS OR IS GENE-SPECIFIC. TO ADDRESS THESE ISSUES, THE TECHNIQUE OF METHYLATION-SPECIFIC PCR AND BISULFITE-SEQUENCING WAS ADAPTED TO STUDY THE REGULATORY REGIONS OF ABL1 AND OTHER GENES. IN CELL LINES ESTABLISHED FROM CML BLAST CRISIS, WHICH ONLY CARRY A SINGLE ABL1 ALLELE NESTED WITHIN THE BCR-ABL FUSION GENE, ABL1 PROMOTERS WERE UNIVERSALLY METHYLATED. IN CLINICAL SAMPLES FROM PATIENTS AT ADVANCED STAGES OF THE DISEASE, BOTH METHYLATED AND UNMETHYLATED PROMOTER ALLELES WERE DETECTABLE. IN COLONIES DERIVED FROM SINGLE HEMATOPOIETIC PROGENITORS METHYLATED AND UNMETHYLATED PROMOTER ALLELES WERE REVEALED AS WELL. ABL1 METHYLATION WAS WAS NOTED IN THE VAST MAJORITY OF COLONIES FROM BLAST CRISIS, BUT NOT CHRONIC-PHASE CML. IT WAS SHOWN FINALLY THAT ABL1 METHYLATION DOES NOT REFLECT A GENERALIZED PROCESS AND MAY BE UNIQUE AMONG DNA REPAIR/GENOTOXIC STRESS RESPONSE GENES. THESE DATA SUGGEST THAT SPECIFIC METHYLATION OF THE PH'-ASSOCIATED ABL1 ALLELE ACCOMPANIES CLONAL EVOLUTION IN CML. 2000 17 2261 30 EPIGENETIC PROFILE IN CHRONIC LYMPHOCYTIC LEUKEMIA USING METHYLATION-SPECIFIC MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION. AIM: TO ANALYZE THE METHYLATION STATUS OF 35 TUMOR SUPPRESSOR GENES USING METHYLATION-SPECIFIC MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION (MS-MLPA) IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). MATERIALS & METHODS: THE DNA OF 37 SAMPLES FROM PATIENTS WITH CLL, SIX HEALTHY DONORS, AND JURKAT AND RAMOS CELL LINES WAS ANALYZED BY MS-MLPA. RESULTS: OUR RESULTS CONFIRM THAT HYPERMETHYLATION IS A COMMON AND NOT RANDOMLY DISTRIBUTED EVENT IN CLL, AND SOME GENES, SUCH AS WT1, CDH13, IGSF4/TSLC1, GATA5, DAPK1 AND RARB, ARE HYPERMETHYLATED IN MORE THAN 25% OF THE ANALYZED SAMPLES. IMPORTANTLY, MS-MLPA ALSO DETECTED HYPERMETHYLATION OF SOME GENES NOT REPORTED PREVIOUSLY IN CLL, AND THEIR METHYLATION STATUS WAS CONFIRMED BY BISULFITE SEQUENCING. CONCLUSION: THESE RESULTS INDICATE THAT MS-MLPA IS A USEFUL TECHNIQUE FOR THE DETECTION OF METHYLATION IN CLL SAMPLES. SELECTING CLL-SPECIFIC METHYLATION TARGETS IN ORDER TO GENERATE A CLL-SPECIFIC MS-MLPA PROBE SET COULD ENHANCE ITS USEFULNESS AS A TOOL IN STUDIES OF RISK STRATIFICATION AND GUIDING THE BEST THERAPEUTIC DECISION. 2012 18 5917 46 TARGETING BCL-2 IN B-CELL MALIGNANCIES AND OVERCOMING THERAPEUTIC RESISTANCE. DEFECTS IN APOPTOSIS CAN PROMOTE TUMORIGENESIS AND IMPAIR RESPONSES OF MALIGNANT B CELLS TO CHEMOTHERAPEUTICS. MEMBERS OF THE B-CELL LEUKEMIA/LYMPHOMA-2 (BCL-2) FAMILY OF PROTEINS ARE KEY REGULATORS OF THE INTRINSIC, MITOCHONDRIAL APOPTOTIC PATHWAY. OVEREXPRESSION OF ANTIAPOPTOTIC BCL-2 FAMILY PROTEINS IS ASSOCIATED WITH TREATMENT RESISTANCE AND POOR PROGNOSIS. THUS, INHIBITION OF BCL-2 FAMILY PROTEINS IS A RATIONAL THERAPEUTIC OPTION FOR MALIGNANCIES THAT ARE DEPENDENT ON ANTIAPOPTOTIC BCL-2 FAMILY PROTEINS. VENETOCLAX (ABT-199, GDC-0199) IS A HIGHLY SELECTIVE BCL-2 INHIBITOR THAT REPRESENTS THE FIRST APPROVED AGENT OF THIS CLASS AND IS CURRENTLY WIDELY USED IN THE TREATMENT OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) AS WELL AS ACUTE MYELOID LEUKEMIA (AML). DESPITE IMPRESSIVE CLINICAL ACTIVITY, VENETOCLAX MONOTHERAPY FOR A PROLONGED DURATION CAN LEAD TO DRUG RESISTANCE OR LOSS OF DEPENDENCE ON THE TARGETED PROTEIN. IN THIS REVIEW, WE PROVIDE AN OVERVIEW OF THE MECHANISM OF ACTION OF BCL-2 INHIBITION AND THE ROLE OF THIS APPROACH IN THE CURRENT TREATMENT PARADIGM OF B-CELL MALIGNANCIES. WE SUMMARIZE THE DRIVERS OF DE NOVO AND ACQUIRED RESISTANCE TO VENETOCLAX THAT ARE CLOSELY ASSOCIATED WITH COMPLEX CLONAL SHIFTS, INTERPLAY OF EXPRESSION AND INTERACTIONS OF BCL-2 FAMILY MEMBERS, TRANSCRIPTIONAL REGULATORS, AND METABOLIC MODULATORS. WE ALSO EXAMINE HOW TUMORS INITIALLY RESISTANT TO VENETOCLAX BECOME RESPONSIVE TO IT FOLLOWING PRIOR THERAPIES. HERE, WE SUMMARIZE PRECLINICAL DATA PROVIDING A RATIONALE FOR EFFICACIOUS COMBINATION STRATEGIES OF VENETOCLAX TO OVERCOME THERAPEUTIC RESISTANCE BY A TARGETED APPROACH DIRECTED AGAINST ALTERNATIVE ANTIAPOPTOTIC BCL-2 FAMILY PROTEINS (MCL-1, BCL-XL), COMPENSATORY PROSURVIVAL PATHWAYS, EPIGENETIC MODIFIERS, AND DYSREGULATED CELLULAR METABOLISM/ENERGETICS FOR DURABLE CLINICAL REMISSIONS. 2020 19 5283 37 PROPHYLACTIC OR PREEMPTIVE LOW-DOSE AZACITIDINE AND DONOR LYMPHOCYTE INFUSION TO PREVENT DISEASE RELAPSE FOLLOWING ALLOGENEIC TRANSPLANTATION IN PATIENTS WITH HIGH-RISK ACUTE MYELOGENOUS LEUKEMIA OR MYELODYSPLASTIC SYNDROME. BECAUSE OF THE PERSISTENTLY HIGH RATES OF RELAPSE OF PATIENTS WITH HIGH-RISK ACUTE MYELOGENOUS LEUKEMIA (AML) AND MYELODYSPLASTIC SYNDROME (MDS) FOLLOWING ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION (ALLO-HSCT), POST-TRANSPLANTATION MAINTENANCE THERAPY HAS BEEN PROPOSED. WE PREVIOUSLY INITIATED A PHASE II TRIAL IN WHICH EPIGENETIC THERAPY WAS COMBINED WITH IMMUNOTHERAPY IN AN ATTEMPT TO REDUCE DISEASE RELAPSE. IN THAT STUDY, LOW-DOSE AZACITIDINE (AZA) AND ESCALATING DOSES OF DONOR LYMPHOCYTE INFUSION (DLI) WERE GIVEN AS POST-ALLO-HSCT MAINTENANCE TREATMENT. IN THE PRESENT STUDY, WE RETROSPECTIVELY ANALYZE A LARGER COHORT OF PATIENTS RECEIVING POST-TRANSPLANTATION MAINTENANCE THERAPY AND PROVIDE UPDATES ON SOME PATIENTS OF THE EARLIER STUDY. THE OBJECTIVES OF THE PRESENT STUDY WERE TO ANALYZE THE CUMULATIVE INCIDENCE OF RELAPSE (CIR), OVERALL SURVIVAL (OS), AND PROGRESSION-FREE SURVIVAL (PFS) AND THE INCIDENCE OF ACUTE AND CHRONIC GRAFT-VERSUS-HOST DISEASE (GVHD) OF PATIENTS WITH HIGH-RISK AML OR MDS RECEIVING POST-TRANSPLANTATION MAINTENANCE TREATMENT WITH AZA WITH OR WITHOUT DLI. WE RETROSPECTIVELY ANALYZED 77 PATIENTS (54 WITH AML, 23 WITH MDS) CONSIDERED AT HIGH RISK BASED ON EITHER THEIR GENOMIC OR CLINICAL STATUS AT TRANSPLANTATION. FOLLOWING ALLOGENEIC TRANSPLANTATION, THEY RECEIVED AT LEAST 1 CYCLE OF PROPHYLACTIC OR PREEMPTIVE LOW-DOSE AZA WITH OR WITHOUT ESCALATING DOSES OF DLI TO PREVENT DISEASE RELAPSE. ALMOST ONE-HALF OF THE PATIENTS (47%) WERE ABLE TO RECEIVE THE FULL 12 CYCLES OF SCHEDULED AZA, AND A MAJORITY (79%) RECEIVED AT LEAST 1 DLI. WITH A MEDIAN FOLLOW-UP OF 24 MONTHS, 19 PATIENTS (25%; 16 WITH AML, 3 WITH MDS) RELAPSED, AT A MEDIAN OF 9.8 MONTHS (RANGE, 4 TO 58.6 MONTHS), GIVING A 22% CIR AT 24 MONTHS. OS AND PFS AT 24 MONTHS WERE 70.8% AND 68.3%, RESPECTIVELY. THE CUMULATIVE INCIDENCES OF GRADE II-IV ACUTE GVHD AND CHRONIC GVHD WERE 27.4% AND 45%, RESPECTIVELY. ONLY A MINORITY OF PATIENTS (11%) REQUIRED DELAYED ADMINISTRATION OF AZA. THESE FINDINGS CONFIRM THAT AZA-DLI MAINTENANCE IS BOTH TOLERABLE AND EFFECTIVE IN REDUCING THE RISK OF POST-TRANSPLANTATION RELAPSE. 2021 20 18 25 5-AZACYTIDINE MODULATES CPG METHYLATION LEVELS OF EZH2 AND NOTCH1 IN MYELODYSPLASTIC SYNDROMES. PURPOSE: MOLECULAR MECHANISMS OF RESPONSE TO HYPOMETHYLATING AGENTS IN PATIENTS WITH MYELODYSPLASTIC SYNDROMES (MDS) AND CHRONIC MYELOMONOCYTIC LEUKEMIA (CMML) STILL REMAIN LARGELY UNKNOWN. THEREFORE, THE EFFECTS OF 5-AZACYTIDINE (AZA) ON CLONAL ARCHITECTURE AND DNA METHYLATION WERE INVESTIGATED IN THIS STUDY. METHODS: USING NEXT-GENERATION SEQUENCING (NGS), 30 MYELOID LEUKEMIA-ASSOCIATED GENES WERE ANALYZED IN 15 MDS/CMML PATIENTS WITH EXCELLENT RESPONSE TO AZA. EFFECTS ON METHYLATION LEVELS WERE ANALYZED BY QUANTITATIVE METHYLATION ANALYSIS USING PYROSEQUENCING FOR THE GLOBAL METHYLATION MARKER LINE-1 IN PATIENTS AND MYELOID CELL LINES. VARIOUS MYELOID CELL LINES AND A HEALTHY COHORT WERE SCREENED FOR METHYLATION LEVELS IN 23 GENES. SELECTED TARGETS WERE VERIFIED ON THE MDS/CMML COHORT. RESULTS: THE STUDY PRESENTED HERE SHOWED A STABLE VARIANT ALLELE FREQUENCY AND STABLE GLOBAL METHYLATION LEVELS IN RESPONDING PATIENTS. A SIGNIFICANT DEMETHYLATION OF EZH2 AND NOTCH1 WAS REVEALED IN PATIENTS WITH AZA RESPONSE. CONCLUSIONS: A RESPONSE TO AZA IS NOT ASSOCIATED WITH ERADICATION OF MALIGNANT CLONES, BUT RATHER WITH A STABILIZATION OF THE CLONAL ARCHITECTURE. WE SUGGEST CHANGES IN CPG METHYLATION LEVELS OF EZH2 AND NOTCH1 AS POTENTIAL TARGETS OF EPIGENETIC RESPONSE TO AZA TREATMENT WHICH MAY ALSO SERVE AS USEFUL BIOMARKERS AFTER CLINICAL EVALUATION. 2019