1 1046 129 CLINICAL DEVELOPMENT OF DECITABINE AS A PROTOTYPE FOR AN EPIGENETIC DRUG PROGRAM. THIS REVIEW HIGHLIGHTS DECITABINE AS A PROTOTYPE EPIGENETIC MODIFYING DRUG TO SHOW HOW THE CLINICAL DEVELOPMENT OF EPIGENETIC AGENTS DIFFERS FROM THAT OF TRADITIONAL CYTOTOXIC CHEMOTHERAPIES. DECITABINE, A CYTOSINE ANALOGUE, IS CYTOTOXIC AT HIGH DOSES BUT HAS SELECTIVE DNA DEMETHYLATING ACTIVITY AT LOW DOSES. THE FOCUS OF CURRENT DECITABINE INVESTIGATIONS IS TWOFOLD: TO ELUCIDATE ALL OF THE MECHANISMS OF ACTION AND TO DETERMINE THE OPTIMAL DOSE, SCHEDULE, AND CONCOMITANT THERAPIES. NEW PHASE I TRIALS HAVE IDENTIFIED A "BIOLOGICALLY EFFECTIVE DOSE," WHICH IS 1 TO 2 LOGS LOWER THAN THE CYTOTOXIC DOSE. A CLINICAL DEVELOPMENT PROGRAM WITH LOW-DOSE DECITABINE IN MALIGNANT DISEASES IS FOCUSED ON MYELODYSPLASTIC SYNDROME (MDS), ACUTE MYELOGENOUS LEUKEMIA (AML), AND CHRONIC MYELOGENOUS LEUKEMIA (CML). A PHASE III TRIAL IN MDS SHOWED OBJECTIVE RESPONSES (COMPLETE [CR] PLUS PARTIAL [PR] REMISSION) AND LONGER MEDIAN TIME TO PROGRESSION TO AML OR DEATH WITH DECITABINE THAN WITH SUPPORTIVE CARE ALONE. THE OPTIMAL USE OF DECITABINE MAY BE IN COMBINATION WITH OTHER AGENTS THAT PROMOTE GENE EXPRESSION, NAMELY, HISTONE DEACETYLASE (HDAC) INHIBITORS. OPTIMIZED DECITABINE DOSES AND COMBINATIONS WITH OTHER EPIGENETIC THERAPIES THAT CAN BE USED AT MINIMALLY TOXIC DOSES PROVIDE POTENTIALLY SAFER THERAPEUTIC OPTIONS AND INTRODUCE NOVEL COMBINATION THERAPIES. 2005 2 1242 45 CURRENT AND NOVEL THERAPEUTIC APPROACHES IN MYELODYSPLASTIC SYNDROMES. MYELODYSPLASTIC SYNDROMES (MDS) ARE A HETEROGENEOUS GROUP OF HEMATOLOGIC NEOPLASMS WITH AN ANNUAL INCIDENCE OF 4.1 CASES PER 100,000 AMERICANS. PATIENTS WITH MDS SUFFER FROM CHRONIC CYTOPENIAS THAT MAY LEAD TO RECURRENT TRANSFUSIONS, INFECTIONS, AND INCREASED RISK FOR BLEEDING. THEY ARE ALSO AT RISK FOR PROGRESSION TO ACUTE MYELOID LEUKEMIA. ALLOGENEIC HEMATOPOIETIC CELL TRANSPLANTATION IS THE ONLY POTENTIALLY CURATIVE TREATMENT FOR MDS, ALTHOUGH 3 DRUGS HAVE BEEN APPROVED BY THE US FOOD AND DRUG ADMINISTRATION FOR ITS TREATMENT: LENALIDOMIDE, 5-AZACITIDINE, AND DECITABINE. THESE THERAPIES CAN BE EFFECTIVE IN THE RELIEF OF CYTOPENIAS, ACHIEVEMENT OF CYTOGENETIC REMISSIONS, AND REDUCTION IN BONE MARROW BLASTS. 5-AZACITIDINE HAS ALSO BEEN SHOWN TO IMPROVE OVERALL SURVIVAL. HOWEVER, THERE REMAIN MANY UNMET NEEDS IN THE TREATMENT OF MDS. BREAKTHROUGHS IN OUR UNDERSTANDING OF THE COMPLEX PATHOGENESIS OF MDS THROUGH EPIGENETIC, GENETIC, IMMUNOLOGIC, AND OTHER BIOLOGICAL MECHANISMS HAVE ALLOWED US TO DEVELOP NEW THERAPEUTIC STRATEGIES THAT CAN LEAD TO IMPROVEMENTS IN OUTCOMES IN MDS. IN THIS REVIEW, WE AIM TO PROVIDE AN OVERVIEW OF THE EVOLUTION IN CLASSIFCATION AND RISK STRATIFCATION IN MDS AND TO ILLUSTRATE HOW WE CAN USE THIS TO GUIDE US IN TAILORING THERAPEUTIC CHOICES IN THIS DISEASE. RESPONSES AND OUTCOMES RELATED TO COM MONLY USED MDS THERAPIES WILL BE DISCUSSED TOGETHER WITH NOVEL THERAPIES THAT HAVE EVOLVED WITH THE IMPROVED UNDERSTANDING OF MDS PATHOPHYSIOLOGY. 2014 3 6574 28 TREATMENT OF CHRONIC MYELOMONOCYTIC LEUKEMIA WITH 5-AZACYTIDINE: CASE REPORTS. EPIGENETIC THERAPY WITH HYPOMETHYLATING AGENT (5-AZACYTIDINE; AZA) IS COMMON IN THE MANAGEMENT OF SPECIFIC SUBTYPES OF MYELODYSPLASTIC SYNDROME (MDS), BUT THERE ARE ONLY FEW STUDIES IN CHRONIC MYELOMONOCYTIC LEUKEMIA (CMML) PATIENTS. IN THIS PAPER OUR EXPERIENCE WITH 3 CMML PATIENTS TREATED WITH AZA IS DESCRIBED. IN ONE PATIENT TRANSFUSION INDEPENDENCY WAS OBSERVED AFTER 4 TREATMENT CYCLES; IN ONE CASE A PARTIAL RESPONSE WAS RECORDED, BUT A PROGRESSION TO ACUTE MYELOID LEUKEMIA (AML) AFTER 13 AZA CYCLES HAS APPEARED. IN ONE PATIENT, AZA IN REDUCED DOSAGE WAS ADMINISTERED AS A BRIDGING TREATMENT BEFORE ALLOGENEIC STEM CELL TRANSPLANTATION (ASCT), BUT IN THE CONTROL BONE MARROW ASPIRATE (BEFORE ASCT) A PROGRESSION TO AML WAS RECORDED. FUTURE STUDIES ARE MANDATORY FOR EVALUATION OF NEW MOLECULAR AND CLINICAL FEATURES WHICH COULD PREDICT THE EFFICIENCY OF HYPOMETHYLATING AGENTS IN CMML THERAPY WITH RESPECT TO OVERALL SURVIVAL, EVENT-FREE SURVIVAL, QUALITY-ADJUSTED LIFE YEAR, AND PHARMACOECONOMY. 2012 4 1616 39 DNA METHYLTRANSFERASE AND HISTONE DEACETYLASE INHIBITORS IN THE TREATMENT OF MYELODYSPLASTIC SYNDROMES. THE RECENTLY APPROVED DRUGS 5-AZACITIDINE (5AC) AND 5-AZA-2'-DEOXYAZACYTIDINE (DAC) ARE IN WIDE CLINICAL USE FOR THE TREATMENT OF MYELODYSPLASTIC SYNDROME (MDS) OF ALL TYPES AND CHRONIC MYELOMONOCYTIC LEUKEMIA (CMML). THESE AGENTS WERE DEVELOPED BASED UPON AN UNDERSTANDING OF THE IMPORTANCE OF EPIGENETIC CHANGES IN MALIGNANCY, AND THEY HAVE BEEN EVALUATED IN RANDOMIZED CLINICAL TRIALS, WHICH DEMONSTRATE RESPONSE RATES BETWEEN 20% AND 40% IN PATIENTS FOR WHOM NO PREVIOUS STANDARD OF CARE WAS AVAILABLE. AS UNDERSTANDING OF THE EPIGENETIC CHANGES CHARACTERISTIC OF THE MALIGNANT PHENOTYPE IMPROVES, WE ARE ABLE TO TARGET OTHER REGULATORS OF CHROMATIN CONFORMATION THAT CONTRIBUTE TO ABERRANT GENE TRANSCRIPTION AND DYSREGULATED CELL GROWTH. THE HISTONE DEACETYLASE (HDAC) INHIBITORS BELONG TO ONE CLASS OF THERAPEUTICS DEVELOPED USING THIS PARADIGM. ALTHOUGH RESPONSES USING HDAC INHIBITORS ALONE IN MDS HAVE BEEN MODEST, ROBUST PRECLINICAL DATA DRIVE CLINICAL TRIALS IN WHICH THEY ARE UTILIZED IN COMBINATION WITH DNA METHYLTRANSFERASE (DNMT) INHIBITORS. COMBINATION THERAPY OFFERS THE POSSIBILITY OF HEMATOLOGIC IMPROVEMENT AND REMISSION TO MYELODYSPLASTIC PATIENTS WITH PREVIOUSLY UNTREATABLE DISEASE. 2008 5 2083 39 EPIGENETIC DRUGS: A LONGSTANDING STORY. IN THIS CHAPTER, THE DEVELOPMENT OF DECITABINE FROM ITS SYNTHESIS IN 1964 TO THE SUBMISSION OF A REGISTRATION FILE IN 2004 IS REVIEWED. THE PROPER APPLICATION OF THE UNIQUE PROPERTIES OF DECITABINE TOOK QUITE SOME TIME TO ELUCIDATE. IN ADDITION, THE PRACTICAL HANDLING IN THE CLINIC WAS NOT EASY AS THE PROLONGED MYELOSUPPRESSION OF DECITABINE MADE IT DIFFICULT TO DETERMINE THE PREFERRED DOSE AND SCHEDULE. LABORATORY STUDIES ON DNA METHYLATION AND CELL DIFFERENTIATION SHOWED POSSIBLE APPLICATIONS IN SOLID AND HEMATOLOGIC MALIGNANCIES. HOWEVER, DESPITE MANY ATTEMPTS, RESULTS IN SOLID TUMORS HAVE BEEN DISAPPOINTING THUS FAR. AFTER THOROUGH INVESTIGATION, DECITABINE ACHIEVED THERAPEUTIC APPLICATION IN MYELODYSPLASTIC SYNDROME (MDS), IN PARTICULAR IN PATIENTS WITH A POOR PROGNOSIS. FURTHER INDICATIONS MAY INCLUDE ACUTE MYELOID LEUKEMIA (AML), CHRONIC MYELOGENOUS LEUKEMIA (CML), HEMATOPOIETIC STEM CELL TRANSPLANTATION, SICKLE CELL ANEMIA, AND THALASSEMIA. WHEREAS MOST DRUGS ARE ALREADY AT THE END OF THEIR LIFE CYCLE AFTER 40 YEARS, DECITABINE IS ONLY AT THE BEGINNING. ITS APPLICATION WILL BROADEN WITH THE INCREASE IN KNOWLEDGE OF EPIGENETIC MECHANISMS AND THEIR RELATIONSHIP TO DRUG THERAPY. 2005 6 1882 35 EMERGING TREATMENTS IN ACUTE MYELOID LEUKAEMIA. ACUTE MYELOID LEUKAEMIA (AML) IS THE MOST COMMON FORM OF LEUKAEMIA IN YOUNG ADULTS. ALTHOUGH 75-85% OF PATIENTS WILL ACHIEVE COMPLETE REMISSION AFTER INDUCTION CHEMOTHERAPY, THE LONG-TERM SURVIVAL IS STILL < 50% AT 5 YEARS. CHEMOTHERAPY HAS INCREASED IN INTENSITY IN RECENT YEARS AND IS PERCEIVED TO HAVE REACHED THE LIMIT OF TOXICITY. ALLOGENEIC BONE MARROW TRANSPLANTATION, WHICH IS UNDOUBTEDLY THE MOST EFFECTIVE WAY TO PREVENT RELAPSE, MAY NOT ADD SUBSTANTIAL SURVIVAL BENEFITS. SEVERAL NEW PHARMACOLOGICAL APPROACHES TO THE TREATMENT OF AML ARE NOW BECOMING AVAILABLE, WITH VARIOUS MOLECULAR TARGETS IDENTIFIED, INCLUDING THE FARNESYLATION OF RAS FAMILY PROTEINS AND TYROSINE KINASES INVOLVED IN SIGNAL TRANSDUCTION AND EPIGENETIC METHYLATION. MORE SELECTIVE DELIVERY OF CHEMOTHERAPEUTIC AGENTS IS ALSO FEASIBLE USING HUMANISED MONOCLONAL ANTIBODIES, WITH THE INTRIGUING POSSIBILITY OF INCREASING TREATMENT DELIVERY WITHOUT INCREASING THE TOXICITY. HOWEVER, DESPITE THE PROGRESS IN THE RATIONAL DESIGN OF DRUGS IN DISORDERS SUCH AS CHRONIC MYELOID LEUKAEMIA, AML LACKS A SINGLE SPECIFIC PATHOGNOMIC GENETIC EVENT TO ACT AS A DRUG TARGET. THIS REVIEW DISCUSSES THE DRUGS PRESENTLY UNDER INVESTIGATION IN PHASE II OR PHASE III TRIALS IN AML. 2004 7 750 26 CARDIAC INVOLVEMENT IN PATIENTS WITH HEMATOLOGIC MALIGNANCIES. AUTHORS HAVE REVIEWED LITERATURE ABOUT THE MANAGEMENT OF PATIENTS WITH CARDIOLOGIC DISEASE OCCURRING SECONDARY TO HEMATOLOGIC PATHOLOGY ITSELF OR ITS THERAPY, WITH A FOCUS ON INFILTRATION OF MYOCARDIUM IN ACUTE AND CHRONIC LEUKEMIA, LYMPHOMA, MULTIPLE MYELOMA, AND HYPEREOSINOPHILIC SYNDROME. MOREOVER, THEY EVALUATED CHEMOTHERAPY-ASSOCIATED TOXICITY, PARTICULARLY FOR NEW DRUGS SUCH AS MONOCLONAL ANTIBODY THERAPY, TYROSINE KINASE INHIBITORS, ARSENIC TRIOXIDE, BORTEZOMIB, AND EPIGENETIC THERAPY. IN FACT, CARDIAC TOXICITY MAY RANGE FROM ASYMPTOMATIC SUBCLINICAL ABNORMALITIES, SUCH AS ELECTROCARDIOGRAPHIC CHANGES AND LEFT VENTRICULAR EJECTION DECLINE, TO LIFE-THREATENING EVENTS AND LEAD TO CHEMOTHERAPY DOSE REDUCTION AND DELAY AND, IN SOME CASES, FOR PATIENTS WITH SEVERE SIDE EFFECTS, DISCONTINUATION OF TREATMENT. FINALLY, THEY DISCUSSED ON THE IDENTIFICATION OF EARLY MARKERS OF CARDIAC INJURY AND ON CARDIAC STEM CELL THERAPY AS A PROMISING APPROACH TO FACILITATE MYOCARDIAL REGENERATION. 2010 8 5499 48 REVIEW: RECENT CLINICAL TRIALS IN EPIGENETIC THERAPY. EPIGENETIC FACTORS SUCH AS DNA METHYLATION AND HISTONE DEACETYLATION ARE KNOWN TO CONTRIBUTE TO THE MALIGNANT TRANSFORMATION OF CELLS BY SILENCING CRITICAL GENES. DRUGS THAT INHIBIT DNA METHYLTRANSFERASES OR HISTONE DEACETYLASES WERE SHOWN TO HAVE THE POTENTIAL TO REACTIVATE SILENCED GENES AND INDUCE DIFFERENTIATION OR APOPTOSIS OF MALIGNANT CELLS. THE MOST INTENSIVELY STUDIED CLASS OF SUCH AGENTS IS DNA METHYLTRANSFERASE INHIBITORS, INCLUDING 5-AZACYTIDINE (AZACITIDINE) AND 5-AZA-2'-DEOXYCYTIDINE (DECITABINE). IN 2004, AZACITIDINE WAS APPROVED FOR THE TREATMENT OF MYELODYSPLASTIC SYNDROME ON THE BASIS OF PHASE II AND III STUDIES THAT SHOWED A RESPONSE RATE (COMPLETE AND PARTIAL RESPONSES) OF 15%. AZACITIDINE IS ALSO BEING EVALUATED IN CLINICAL TRIALS FOR OTHER MALIGNANT DISEASES. DECITABINE HAS RESPONSE RATES OF 17-49% IN MYELODYSPLASTIC SYNDROME IN MULTIPLE PHASE II AND III STUDIES AND ALSO ACTIVITY IN ACUTE AND CHRONIC MYELOGENOUS LEUKEMIA. HISTONE DEACETYLASE INHIBITORS BELONG TO ANOTHER CLASS OF EPIGENETIC MODIFYING AGENTS THAT INCLUDE DEPSIPEPTIDE, BUTYRATE DERIVATIVES, SUBEROYLANILIDE HYDROXAMIC ACID AND VALPROIC ACID. NO AGENT IN THIS CLASS HAS BEEN STUDIED IN A PHASE III TRIAL, BUT SEVERAL AGENTS HAVE BEEN OR ARE BEING STUDIED IN PHASE II TRIALS. FURTHER RESEARCH IS NEEDED TO DETERMINE THE APPROPRIATE PATIENT SELECTION AND DOSING SCHEDULES. 2006 9 5613 36 SAFETY AND EFFICACY OF ABEXINOSTAT, A PAN-HISTONE DEACETYLASE INHIBITOR, IN NON-HODGKIN LYMPHOMA AND CHRONIC LYMPHOCYTIC LEUKEMIA: RESULTS OF A PHASE II STUDY. HISTONE DEACETYLASE INHIBITORS ARE MEMBERS OF A CLASS OF EPIGENETIC DRUGS THAT HAVE PROVEN ACTIVITY IN T-CELL MALIGNANCIES, BUT LITTLE IS KNOWN ABOUT THEIR EFFICACY IN B-CELL LYMPHOMAS. ABEXINOSTAT IS AN ORALLY AVAILABLE HYDROXAMATE-CONTAINING HISTONE DEACETYLASE INHIBITOR THAT DIFFERS FROM APPROVED INHIBITORS; ITS UNIQUE PHARMACOKINETIC PROFILE AND ORAL DOSING SCHEDULE, TWICE DAILY FOUR HOURS APART, ALLOWS FOR CONTINUOUS EXPOSURE AT CONCENTRATIONS REQUIRED TO EFFICIENTLY KILL TUMOR CELLS. IN THIS PHASE II STUDY, PATIENTS WITH RELAPSED/REFRACTORY NON-HODGKIN LYMPHOMA OR CHRONIC LYMPHOCYTIC LEUKEMIA RECEIVED ORAL ABEXINOSTAT AT 80 MG BID FOR 14 DAYS OF A 21-DAY CYCLE AND CONTINUED UNTIL PROGRESSIVE DISEASE OR UNACCEPTABLE TOXICITY. A TOTAL OF 100 PATIENTS WITH B-CELL MALIGNANCIES AND T-CELL LYMPHOMAS WERE ENROLLED BETWEEN OCTOBER 2011 AND JULY 2014. ALL PATIENTS RECEIVED AT LEAST ONE DOSE OF STUDY DRUG. PRIMARY REASONS FOR DISCONTINUATION INCLUDED PROGRESSIVE DISEASE (56%) AND ADVERSE EVENTS (25%). GRADE 3 OR OVER ADVERSE EVENTS AND ANY SERIOUS ADVERSE EVENTS WERE REPORTED IN 88% AND 73% OF PATIENTS, RESPECTIVELY. THE MOST FREQUENTLY REPORTED GRADE 3 OR OVER TREATMENT-EMERGENT RELATED ADVERSE EVENTS WERE THROMBOCYTOPENIA (80%), NEUTROPENIA (27%), AND ANEMIA (12%). AMONG THE 87 PATIENTS EVALUABLE FOR EFFICACY, OVERALL RESPONSE RATE WAS 28% (COMPLETE RESPONSE 5%), WITH HIGHEST RESPONSES OBSERVED IN PATIENTS WITH FOLLICULAR LYMPHOMA (OVERALL RESPONSE RATE 56%), T-CELL LYMPHOMA (OVERALL RESPONSE RATE 40%), AND DIFFUSE LARGE B-CELL LYMPHOMA (OVERALL RESPONSE RATE 31%). FURTHER INVESTIGATION OF THE SAFETY AND EFFICACY OF ABEXINOSTAT IN FOLLICULAR LYMPHOMA, T-CELL LYMPHOMA, AND DIFFUSE LARGE B-CELL LYMPHOMA IMPLEMENTING A LESS DOSE-INTENSE WEEK-ON-WEEK-OFF SCHEDULE IS WARRANTED. (TRIAL REGISTERED AT: EUDRACT-2009-013691-47). 2017 10 4551 32 MUTATIONAL HIERARCHIES IN MYELODYSPLASTIC SYNDROMES DYNAMICALLY ADAPT AND EVOLVE UPON THERAPY RESPONSE AND FAILURE. CLONAL EVOLUTION IS BELIEVED TO BE A MAIN DRIVER FOR PROGRESSION OF VARIOUS TYPES OF CANCER AND IMPLICATED IN FACILITATING RESISTANCE TO DRUGS. HOWEVER, THE HIERARCHICAL ORGANIZATION OF MALIGNANT CLONES IN THE HEMATOPOIESIS OF MYELODYSPLASTIC SYNDROMES (MDS) AND ITS IMPACT ON RESPONSE TO DRUG THERAPY REMAIN POORLY UNDERSTOOD. USING HIGH-THROUGHPUT SEQUENCING OF PATIENT AND XENOGRAFTED CELLS, WE EVALUATED THE INTRATUMORAL HETEROGENEITY (N= 54) AND RECONSTRUCTED MUTATIONAL TRAJECTORIES (N = 39) IN PATIENTS SUFFERING FROM MDS (N = 52) AND CHRONIC MYELOMONOCYTIC LEUKEMIA-1 (N = 2). WE IDENTIFIED LINEAR AND ALSO BRANCHING EVOLUTION PATHS AND CONFIRMED ON A PATIENT-SPECIFIC LEVEL THAT SOMATIC MUTATIONS IN EPIGENETIC REGULATORS AND RNA SPLICING GENES FREQUENTLY CONSTITUTE ISOLATED DISEASE-INITIATING EVENTS. USING HIGH-THROUGHPUT EXOME- AND/OR DEEP-SEQUENCING, WE ANALYZED 103 CHRONOLOGICALLY ACQUIRED SAMPLES FROM 22 PATIENTS COVERING A CUMULATIVE OBSERVATION TIME OF 75 YEARS MDS DISEASE PROGRESSION. OUR DATA REVEALED HIGHLY DYNAMIC SHAPING OF COMPLEX OLIGOCLONAL ARCHITECTURES, SPECIFICALLY UPON TREATMENT WITH LENALIDOMIDE AND OTHER DRUGS. DESPITE INITIAL CLINICAL RESPONSE TO TREATMENT, PATIENTS' MARROW PERSISTENTLY REMAINED CLONAL WITH RAPID OUTGROWTH OF FOUNDER-, SUB-, OR EVEN FULLY INDEPENDENT CLONES, INDICATING AN INCREASED DYNAMIC RATE OF CLONAL TURNOVER. THE EMERGENCE AND DISAPPEARANCE OF SPECIFIC CLONES FREQUENTLY CORRELATED WITH CHANGES OF CLINICAL PARAMETERS, HIGHLIGHTING THEIR DISTINCT AND FAR-REACHING FUNCTIONAL PROPERTIES. INTRIGUINGLY, INCREASINGLY COMPLEX MUTATIONAL TRAJECTORIES ARE FREQUENTLY ACCOMPANIED BY CLINICAL PROGRESSION DURING THE COURSE OF DISEASE. THESE DATA SUBSTANTIATE A NEED FOR REGULAR BROAD MOLECULAR MONITORING TO GUIDE CLINICAL TREATMENT DECISIONS IN MDS. 2016 11 2547 28 EPIGENETICS IN MYELOID MALIGNANCIES. MYELOID HEMATOLOGICAL MALIGNANCIES ARE AMONG THE EPIGENETICALLY BEST CHARACTERIZED NEOPLASMS. THE COMPARATIVELY LOW NUMBER OF RECURRING BALANCED AND UNBALANCED CHROMOSOMAL ABNORMALITIES AS WELL AS COMMON GENETIC MUTATIONS HAS ENABLED SCIENTISTS TO RELATE EPIGENETIC STATES TO THESE. THE EASE OF ACCESSING MALIGNANT CELLS THROUGH BONE MARROW ASPIRATION HAS CERTAINLY CONTRIBUTED TO THE FAST EXPANSION OF KNOWLEDGE. EVEN SO, THE CLINICAL AND PATHOGENETIC RELEVANCE OF EPIGENETIC CHANGES IS STILL NOT KNOWN, AND THE FIELD WILL CERTAINLY EVOLVE VERY FAST WITH THE DEVELOPMENT OF NEW ANALYTIC TECHNIQUES. THE FIRST EXAMPLE OF SUCCESSFUL EPIGENETIC THERAPY IS SEEN IN MYELOID MALIGNANCIES, IN THE HIGH-RISK MYELODYSPLASTIC SYNDROMES (MDS) WHICH ARE ROUTINELY TREATED WITH THE DEMETHYLATING AGENT AZACYTIDINE.THIS CHAPTER WILL CONCENTRATE ON DESCRIBING THE EPIGENETIC CHANGES IN ACUTE MYELOID LEUKEMIA (AML), CHRONIC MYELOID LEUKEMIA (CML) AND MDS. AN OVERVIEW OF CLINICAL RELEVANCE AND EPIGENETIC THERAPEUTIC APPROACHES IS ALSO MADE. 2012 12 4487 37 MOLECULARLY TARGETED DRUG COMBINATIONS DEMONSTRATE SELECTIVE EFFECTIVENESS FOR MYELOID- AND LYMPHOID-DERIVED HEMATOLOGIC MALIGNANCIES. TRANSLATING THE GENETIC AND EPIGENETIC HETEROGENEITY UNDERLYING HUMAN CANCERS INTO THERAPEUTIC STRATEGIES IS AN ONGOING CHALLENGE. LARGE-SCALE SEQUENCING EFFORTS HAVE UNCOVERED A SPECTRUM OF MUTATIONS IN MANY HEMATOLOGIC MALIGNANCIES, INCLUDING ACUTE MYELOID LEUKEMIA (AML), SUGGESTING THAT COMBINATIONS OF AGENTS WILL BE REQUIRED TO TREAT THESE DISEASES EFFECTIVELY. COMBINATORIAL APPROACHES WILL ALSO BE CRITICAL FOR COMBATING THE EMERGENCE OF GENETICALLY HETEROGENEOUS SUBCLONES, RESCUE SIGNALS IN THE MICROENVIRONMENT, AND TUMOR-INTRINSIC FEEDBACK PATHWAYS THAT ALL CONTRIBUTE TO DISEASE RELAPSE. TO IDENTIFY NOVEL AND EFFECTIVE DRUG COMBINATIONS, WE PERFORMED EX VIVO SENSITIVITY PROFILING OF 122 PRIMARY PATIENT SAMPLES FROM A VARIETY OF HEMATOLOGIC MALIGNANCIES AGAINST A PANEL OF 48 DRUG COMBINATIONS. THE COMBINATIONS WERE DESIGNED AS DRUG PAIRS THAT TARGET NONOVERLAPPING BIOLOGICAL PATHWAYS AND COMPRISE DRUGS FROM DIFFERENT CLASSES, PREFERABLY WITH FOOD AND DRUG ADMINISTRATION APPROVAL. A COMBINATION RATIO (CR) WAS DERIVED FOR EACH DRUG PAIR, AND CRS WERE EVALUATED WITH RESPECT TO DIAGNOSTIC CATEGORIES AS WELL AS AGAINST GENETIC, CYTOGENETIC, AND CELLULAR PHENOTYPES OF SPECIMENS FROM THE TWO LARGEST DISEASE CATEGORIES: AML AND CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). NEARLY ALL TESTED COMBINATIONS INVOLVING A BCL2 INHIBITOR SHOWED ADDITIONAL BENEFIT IN PATIENTS WITH MYELOID MALIGNANCIES, WHEREAS SELECT COMBINATIONS INVOLVING PI3K, CSF1R, OR BROMODOMAIN INHIBITORS SHOWED PREFERENTIAL BENEFIT IN LYMPHOID MALIGNANCIES. EXPANDED ANALYSES OF PATIENTS WITH AML AND CLL REVEALED SPECIFIC PATTERNS OF EX VIVO DRUG COMBINATION EFFICACY THAT WERE ASSOCIATED WITH SELECT GENETIC, CYTOGENETIC, AND PHENOTYPIC DISEASE SUBSETS, WARRANTING FURTHER EVALUATION. THESE FINDINGS HIGHLIGHT THE HEURISTIC VALUE OF AN INTEGRATED FUNCTIONAL GENOMIC APPROACH TO THE IDENTIFICATION OF NOVEL TREATMENT STRATEGIES FOR HEMATOLOGIC MALIGNANCIES. 2017 13 6573 38 TREATMENT OF ACUTE MYELOID LEUKEMIA IN THE ERA OF GENOMICS-ACHIEVEMENTS AND PERSISTING CHALLENGES. ACUTE MYELOID LEUKEMIA (AML) REPRESENTS A MALIGNANT DISORDER OF THE HEMATOPOIETIC SYSTEM THAT IS MAINLY CHARACTERIZED BY RAPID PROLIFERATION, DYSREGULATED APOPTOSIS, AND IMPAIRED DIFFERENTIATION OF LEUKEMIC BLASTS. FOR SEVERAL DECADES, THE DIAGNOSTIC APPROACH IN AML WAS LARGELY BASED ON HISTOLOGIC CHARACTERISTICS WITH LITTLE IMPACT ON THE TREATMENT DECISION-MAKING PROCESS. THIS PERSPECTIVE HAS DRASTICALLY CHANGED WITHIN THE PAST YEARS DUE TO THE ADVENT OF NOVEL MOLECULAR TECHNOLOGIES, SUCH AS WHOLE GENOME NEXT-GENERATION SEQUENCING (NGS), AND THE RESULTING KNOWLEDGE GAIN IN AML BIOLOGY AND PATHOGENESIS. AFTER MORE THAN FOUR DECADES OF INTENSIVE CHEMOTHERAPY AS A "ONE-SIZE-FITS-ALL" CONCEPT, SEVERAL TARGETED AGENTS HAVE RECENTLY BEEN APPROVED FOR THE TREATMENT OF AML, EITHER AS SINGLE AGENTS OR AS PART OF COMBINED TREATMENT REGIMENS. SEVERAL OTHER COMPOUNDS, DIRECTED AGAINST REGULATORS OF APOPTOTIC, EPIGENETIC, OR MICROENVIRONMENTAL PATHWAYS, AS WELL AS MODULATORS OF THE IMMUNE SYSTEM, ARE CURRENTLY IN DEVELOPMENT AND BEING INVESTIGATED IN CLINICAL TRIALS. THE CONSTANT PROGRESS IN AML RESEARCH HAS STARTED TO PRODUCE IMPROVED SURVIVAL RATES AND FUELED HOPES THAT A ONCE RAPIDLY FATAL DISEASE CAN BE TRANSFORMED INTO A CHRONIC CONDITION. IN THIS REVIEW, THE AUTHORS PROVIDE A SUMMARY OF RECENT ADVANCES IN THE DEVELOPMENT OF TARGETED AML THERAPIES AND DISCUSS PERSISTENT CHALLENGES. 2020 14 3934 42 LIVER TUMOR INDUCTION. THE SIGNIFICANCE OF THE DEVELOPMENT OF NODULAR LIVER LESIONS IN RODENTS FOLLOWING THE ADMINISTRATION OF TEST AGENTS RAISES SEVERAL QUESTIONS WHICH COULD BE PLACED IN ONE OF TWO GENERAL CATEGORIES: DIAGNOSTIC AND INTERPRETATIONAL. FROM A DIAGNOSTIC POINT OF VIEW, THE PROPER CLASSIFICATION OF LIVER TUMORS INTO A BENIGN AND MALIGNANT CATEGORY HAS TO BE BASED ON THE DIRECT CORRELATION BETWEEN THE MORPHOLOGY AND THE BIOLOGIC BEHAVIOR OF THE LESIONS. THEREFORE, EXTREME CARE SHOULD BE TAKEN TO SEPARATE THE MALIGNANT TUMORS FROM THE BENIGN AND THE BENIGN NEOPLASIA FROM THE HYPERPLASIA. THE SUBSTITUTION OF THE TERM "NEOPLASTIC NODULE" FOR HYPERPLASTIC NODULE IN RATS IS MISLEADING. MOST OF THESE NODULES, WHEN INDUCED UNDER SPECIAL EXPERIMENTAL CONDITIONS, MAY REGRESS OR REMODEL AND THUS THEY ARE NOT NEOPLASTIC IN NATURE. CHRONIC CARCINOGENICITY BIOASSAYS SHOULD INCLUDE "STOP" TYPE OF TREATMENT LEAVING ENOUGH OF THE OBSERVATIONAL TIME TO ESTABLISH THE FATE OF INDUCED NODULAR LESIONS. THE INDUCTION OF HISTOCHEMICALLY CHANGED FOCI CAN SERVE ONLY AS AN INDICATION OF POTENTIAL HEPATOCARCINOGENICITY AND SHOULD NOT BE EQUATED WITH THE INDUCTION OF BONA FIDE CANCER. THE BIOLOGIC INTERPRETATION OF NODULAR LIVER LESIONS, ESPECIALLY IN MICE, NEEDS FURTHER SCRUTINY BECAUSE THESE LESIONS HAVE A TENDENCY TO DEVELOP SPONTANEOUSLY WITH HIGH INCIDENCE IN SOME STRAINS. THIS CHARACTERISTIC THEN RAISES THE QUESTION AS TO THE MECHANISM BY WHICH VARIOUS AGENTS AUGMENT AND/OR ACCELERATE THE DEVELOPMENT OF SUCH TUMORS. IS THIS ACTION PRIMARILY PROMOTING OR INITIATING IN NATURE OR DOES IT REPRESENT THE INDUCTION OF TUMORS DE NOVO? THE ANSWER TO THIS DILEMMA MAY HAVE A DECISIVE BEARING ON CARCINOGENIC RISK ASSESSMENT AND THE TYPE OF REGULATORY ACTION, SINCE THE PROMOTING AGENTS POSSESS A THRESHOLD EFFECT AND THE PROMOTED CHANGES MAY REGRESS FOLLOWING WITHDRAWAL OF TREATMENT. THE INTERPRETATION OF HEPATOCARCINOGENESIS IS FURTHER COMPLICATED BY THE FACT THAT SEVERAL FACTORS, SUCH AS SEX HORMONAL ENVIRONMENT, INCREASED MITOTIC ACTIVITY FOLLOWING AN EXCESSIVE LOSS OF PARENCHYMAL CELLS, DEGREE OF CALORIC INTAKE, ENZYMATIC COMPLEMENT, AND ANIMALS' AGE AT THE TIME OF THE EXPOSURE TO A TEST AGENT, MAY INFLUENCE THE OUTCOME OF LIVER TUMOR DEVELOPMENT BY MODULATING "INITIATION" AND/OR "PROMOTION" OF CARCINOGENESIS. BROAD FLUCTUATION IN THE HISTORIC INCIDENCE OF LIVER TUMORS FURTHER COMPOUNDS THE COMPLEXITY OF THE PROPER BIOASSAY INTERPRETATION. THE SPECIFICALLY DESIGNED EXPERIMENTS MAY HAVE THE OBJECTIVE TO EXPLORE PREDOMINANTLY THE INITIATING OR PROMOTING EFFECTS OF THE AGENT. SUCH PROTOCOLS SHOULD BE USED WHENEVER NECESSARY TO DIFFERENTIATE BETWEEN THESE TWO MECHANISMS OF ACTION. IN THE CAUCASIANS, THE "SPONTANEOUS" DEVELOPMENT OF THE PRIMARY HEPATOCELLULAR TUMORS IS RARE. THE MAJORITY OF THESE TUMORS ARE MALIGNANT AND RAPIDLY FATAL. ACCORDING TO SOME HUMAN PATHOLOGISTS, THE BENIGN VARIETY OF LIVER TUMORS IS RARE AND IT DOES NOT REPRESENT NECESSARILY A PREMALIGNANT STAGE IN TUMOR DEVELOPMENT. CARCINOMA OF THE LIVER MAY OCCUR IN INFANCY, ESPECIALLY IN MALES BEFORE THE AGE OF 2 YEARS. THIS SUGGESTS A GENETIC CAUSATION OR CARCINOGENIC EXPOSURE IN UTERO. ONE OF THE GEOGRAPHIC FACTORS WHICH SIGNIFICANTLY ENHANCES THE INCIDENCE OF HEPATOCELLULAR CARCINOMA IN HUMANS IS EXPOSURE TO AFLATOXIN B(1) WHICH IS APPARENTLY POTENTIATED BY CONCURRENT LIVER CIRRHOSIS. BECAUSE MANY MORE AGENTS HAVE BEEN FOUND TO BE HEPATOCARCINOGENIC IN MICE AND RATS THAN IN MEN, A QUESTION ARISES AS TO THE DIRECT RELEVANCE OF RODENT STUDIES TO HUMANS. A BALANCED ASSESSMENT OF THE CARCINOGENICITY OF THE AGENT COULD ONLY BE REACHED IN CONSIDERING BOTH THE PHARMACOKINETICS AND THE DEVELOPMENT OF MALIGNANT NEOPLASIA IN OTHER ORGANS. IN THE CASE OF POSITIVE CARCINOGENICITY ASSESSMENT, THE OUTCOME OF THE MUTAGENICITY BIOASSAYS CAN SUGGEST GENIC (GENOTOXIC) OR PARAGENIC (EPIGENETIC) MODE OF ACTION IN MAMMALIAN SYSTEMS. 1982 15 6689 40 VALPROIC ACID AT THERAPEUTIC PLASMA LEVELS MAY INCREASE 5-AZACYTIDINE EFFICACY IN HIGHER RISK MYELODYSPLASTIC SYNDROMES. PURPOSE: EPIGENETIC CHANGES PLAY A ROLE AND COOPERATE WITH GENETIC ALTERATIONS IN THE PATHOGENESIS OF MYELODYSPLASTIC SYNDROMES (MDS). WE CONDUCTED A PHASE II MULTICENTER STUDY ON THE COMBINATION OF THE DNA-METHYLTRANSFERASE INHIBITOR 5-AZACYTIDINE (5-AZA) AND THE HISTONE DEACETYLASE INHIBITOR VALPROIC ACID (VPA) IN PATIENTS WITH HIGHER RISK MDS. EXPERIMENTAL DESIGN: WE ENROLLED 62 PATIENTS WITH MDS (REFRACTORY ANEMIA WITH EXCESS BLASTS, 39 PATIENTS; REFRACTORY ANEMIA WITH EXCESS BLASTS IN TRANSFORMATION, 19 PATIENTS; AND CHRONIC MYELOMANOCYTIC LEUKEMIA (CMML), 4 PATIENTS) AND AN INTERNATIONAL PROGNOSTIC SCORING SYSTEM (IPSS) RATING OF INTERMEDIATE-2 (42 PATIENTS) OR HIGH (20 PATIENTS). VPA WAS GIVEN TO REACH A PLASMA CONCENTRATION OF >50 MICROG/ML, THEN 5-AZA WAS ADDED S.C. AT 75 MG/M(2) FOR 7 DAYS IN EIGHT MONTHLY CYCLES. RESULTS: THE MEDIAN OVERALL SURVIVAL WAS 14.4 MONTHS. AT A MEDIAN FOLLOW-UP OF 12 MONTHS (RANGE, 0.7-21.0), THE DISEASE PROGRESSED IN 20 PATIENTS, WITH 21% CUMULATIVE INCIDENCE OF PROGRESSION. OF 26 PATIENTS WHO COMPLETED EIGHT CYCLES, 30.7% OBTAINED COMPLETE OR PARTIAL REMISSION, 15.4% HAD A MAJOR HEMATOLOGIC IMPROVEMENT, WHEREAS 38.5% SHOWED STABLE DISEASE. DRUG-RELATED TOXICITY WAS MILD. FAVORABLE PROGNOSTIC FACTORS FOR SURVIVAL WERE IPSS INTERMEDIATE-2 AND PLASMA VPA OF > OR =50 MICROG/ML (LOG RANK = 0.013 AND 0.007, RESPECTIVELY). ANALYSIS OF POLYMORPHISMS IMPORTANT FOR THE METABOLISM OF THE DRUGS USED IN THE TRIAL SHOWED THAT CARRIERS OF THE CYP2C19*2 VARIANT OF CYTOCHROME P450 REQUIRED HIGHER VPA DOSES TO ACHIEVE THE TARGET VPA PLASMA CONCENTRATION OF 50 MICROG/ML ON DAY 1 OF 5-AZA TREATMENT (P = 0.0021). CONCLUSION: OUR DATA SHOW THAT THE 5-AZA/VPA COMBINATION IS ACTIVE AND SAFE IN PATIENTS WITH MDS WITH A POOR PROGNOSIS. ACHIEVEMENT OF VPA THERAPEUTIC LEVELS MAY INDEED INCREASE 5-AZA EFFICACY. 2009 16 6857 38 [NOVEL CONVENTIONAL THERAPIES IN ONCO-HEMATHOLOGY]. CYTOGENETIC, MOLECULAR AND PHENOTYPING FEATURES OF MALIGNANT HEMATOLOGIC DISEASES SUCCEEDED IN IMPROVING THEIR MANAGEMENT BY A MORE ACCURATE STRATIFICATION OF PATIENTS ACCORDING TO SEVERAL GROUPS OF RISK AND BY PROVIDING A RATIONAL FOR TARGETED THERAPY. THREE MAJOR TYPES OF TREATMENT (EXCLUDING CELLULAR THERAPY) ARE CURRENTLY AVAILABLE IN ONCO-HEMATOLOGY: CONVENTIONAL CHEMOTHERAPY, SMALL MOLECULES FOR TARGETED THERAPY AND MONOCLONAL ANTIBODIES. CONVENTIONAL CHEMOTHERAPY WITH OPTIMIZATION OF DOSES AND MULTIDRUG-BASED REGIMENS ALLOWED TO SUBSTANTIALLY IMPROVE SURVIVAL OF PATIENTS AND KEEPS A PLACE OF CHOICE IN TREATMENT OF THESE DISEASES. TARGETED TREATMENTS CAME FROM THE CYTOGENETIC AND MOLECULAR CHARACTERIZATION OF HEMOPATHIES. THUS, THE KINASE BCR-ABL, AS A RESULT OF THE TRANSLOCATION T(9;22)(Q34;Q11), HAS BEEN SUCCESSFULLY TARGETED BY TYROSINE KINASE INHIBITORS (TKI) IN CHRONIC MYELOID LEUKEMIA AND PH+ ACUTE LYMPHOBLASTIC LEUKEMIA. MOLECULAR ABNORMALITIES LIKE INTERNAL-TANDEM DUPLICATION/POINT ACTIVATING MUTATIONS IN FLT3 IN SOME ACUTE MYELOBLASTIC LEUKEMIA OR EPIGENETIC DYSREGULATIONS IN SOME BLOOD MALIGNANCIES CAN ALSO BE TARGETED BY SMALL MOLECULES. HEMATOPOIETIC MALIGNANT CELLS ARE PHENOTYPICALLY CHARACTERIZED BY EXPRESSION OF CLUSTER OF DIFFERENTIATION (CD) ON THEIR SURFACE. THESE CD ARE DETECTED BY FLOW CYTOMETRY USING SPECIFIC ANTIBODIES. MONOCLONAL ANTIBODIES TARGETING DIFFERENT CD HAVE BEEN DEVELOPED FOR TREATMENT. RITUXIMAB, AN ANTI-CD20 ANTIBODY, WAS THE FIRST MONOCLONAL ANTIBODY SUCCESSFULLY DEVELOPED FOR TREATMENT OF MALIGNANT HEMATOLOGIC DISEASES. SINCE RITUXIMAB, MANY OTHER MONOCLONAL ANTIBODIES ARE BEING DEVELOPED. TRENDS IN MALIGNANT HEMATOLOGIC DISEASES PRESENTED HERE WILL INCLUDE TREATMENTS, WHICH HAVE AT LEAST ENTERED PHASE I/II CLINICAL TRIALS IN ADULT OR CHILDHOOD LEUKEMIA. THEY INCLUDE SOME NOVEL DRUGS OF CONVENTIONAL CHEMOTHERAPY LIKE SECOND-GENERATION NUCLEOSIDE ANALOGUES. WE WILL GIVE AN OVERVIEW OF THE SMALL MOLECULES TARGETING THE DIFFERENT CELLULAR PATHWAYS AND WE WILL HIGHLIGHT THOSE APPEARING AS THE MOST PROMISING LIKE NOVEL TKIS. THE LARGE FIELD OF MONOCLONAL ANTIBODIES WILL BE ALSO APPROACHED FOCUSING ON ANTIBODIES DEVELOPED IN LEUKEMIAS. 2011 17 2770 30 EXTENDING INJURY- AND DISEASE-RESISTANT CNS PHENOTYPES BY REPETITIVE EPIGENETIC CONDITIONING. SIGNIFICANT REDUCTIONS IN THE EXTENT OF ACUTE INJURY IN THE CNS CAN BE ACHIEVED BY EXPOSURE TO DIFFERENT PRECONDITIONING STIMULI, BUT THE DURATION OF THE INDUCED PROTECTIVE PHENOTYPE IS TYPICALLY SHORT-LASTING, AND THUS IS DEEMED AS LIMITING ITS CLINICAL APPLICABILITY. EXTENDING THE PERIOD OVER WHICH SUCH ADAPTIVE EPIGENETIC CHANGES PERSIST - IN EFFECT, EXPANDING CONDITIONING'S "THERAPEUTIC WINDOW" - WOULD SIGNIFICANTLY BROADEN THE POTENTIAL APPLICATIONS OF SUCH A TREATMENT APPROACH IN PATIENTS. THE FREQUENCY OF THE CONDITIONING STIMULUS MAY HOLD THE KEY. WHILE TRANSIENT (1-3 DAYS) PROTECTION AGAINST CNS ISCHEMIC INJURY IS WELL ESTABLISHED PRECLINICALLY FOLLOWING A SINGLE PRECONDITIONING STIMULUS, REPETITIVELY PRESENTING PRECONDITIONING STIMULI EXTENDS THE DURATION OF ISCHEMIC TOLERANCE BY MANY WEEKS. MOREOVER, REPETITIVE INTERMITTENT POSTCONDITIONING ENHANCES POST-ISCHEMIC RECOVERY METRICS AND IMPROVES LONG-TERM SURVIVAL. INTERMITTENT CONDITIONING IS ALSO EFFICACIOUS FOR PREVENTING OR DELAYING INJURY IN PRECLINICAL MODELS OF CHRONIC NEURODEGENERATIVE DISEASE, AND FOR PROMOTING LONG-LASTING FUNCTIONAL IMPROVEMENTS IN A NUMBER OF OTHER PATHOLOGIES AS WELL. ALTHOUGH THE DETAILED MECHANISMS UNDERLYING THESE PROTRACTED KINDS OF NEUROPLASTICITY REMAIN LARGELY UNSTUDIED, ACCUMULATING EMPIRICAL EVIDENCE SUPPORTS THE CONTENTION THAT ALL OF THESE ADAPTIVE PHENOTYPES ARE EPIGENETICALLY MEDIATED. GOING FORWARD, ADDITIONAL PRECLINICAL DEMONSTRATIONS OF THE ABILITY TO INDUCE SUSTAINED BENEFICIAL PHENOTYPES THAT REDUCE THE BURDEN OF ACUTE AND CHRONIC NEURODEGENERATION, AND EXPERIMENTAL INTERROGATIONS OF THE REGULATORY CONSTRUCTS RESPONSIBLE FOR THESE EPIGENETIC RESPONSES, WILL ACCELERATE THE IDENTIFICATION OF NOT ONLY EFFICACIOUS BUT ALSO PRACTICAL, ADAPTIVE EPIGENETICS-BASED TREATMENTS FOR INDIVIDUALS WITH NEUROLOGICAL DISEASE. 2015 18 32 40 A CASE OF TYROSINE KINASE INHIBITOR-RESISTANT CHRONIC MYELOID LEUKEMIA, CHRONIC PHASE WITH ASXL1 MUTATION. HEMATOLOGICAL MALIGNANCIES, INCLUDING CHRONIC MYELOID LEUKEMIA (CML), EXHIBIT ASXL1 MUTATIONS; HOWEVER, THE FUNCTION AND MOLECULAR MECHANISM OF THESE MUTATIONS REMAIN UNCLEAR. ASXL1 WAS ORIGINALLY IDENTIFIED AS TUMOR SUPPRESSOR GENE, IN WHICH LOSS OF FUNCTION CAUSES MYELODYSPLASTIC SYNDROME (MDS). ASXL1 MUTATIONS ARE COMMON AND ASSOCIATED WITH DISEASE PROGRESSION IN MYELOID MALIGNANCIES INCLUDING MDS, ACUTE MYELOID LEUKEMIA, AND SIMILARLY IN CML. IN MDS, ASXL1 MUTATIONS HAVE BEEN ASSOCIATED WITH POOR PROGNOSIS; HOWEVER, THE IMPACT OF ASXL1 MUTATIONS IN CML HAS NOT BEEN WELL DESCRIBED. A 31-YEAR-OLD MALE WAS DIAGNOSED AS CML-CHRONIC PHASE (CP). LABORATORY FINDINGS SHOWED A WHITE BLOOD CELL COUNT OF 187,200/MICROL, WITH ASYMPTOMATIC SPLENOMEGALY. BLAST COUNT WAS 5.0% IN PERIPHERAL BLOOD AND 7.3% IN BONE MARROW. THERE WAS NO ADDITIONAL CHROMOSOMAL ABNORMALITY EXCEPT FOR T(9;22)(Q34;Q11.2) BY CHROMOSOMAL ANALYSIS. AT ONSET, THE SOKAL SCORE WAS 1.4, INDICATING HIGH RISK. THE PATIENT RECEIVED TYROSINE KINASE INHIBITOR (TKI) THERAPY, COMPRISING NILOTINIB APPROXIMATELY 600 MG/DAY, BOSUTINIB APPROXIMATELY 600 MG/DAY, PONATINIB APPROXIMATELY 45 MG/DAY, AND DASATINIB APPROXIMATELY 100 MG/DAY. NEVERTHELESS, AFTER 1.5 YEARS OF CONTINUOUS TKI THERAPY, THE BEST OUTCOME WAS A HEMATOLOGICAL RESPONSE. ALTHOUGH ADDITIONAL CHROMOSOMAL ABERRATIONS AND ABL1 KINASE MUTATIONS WERE ANALYZED REPEATEDLY BEFORE AND DURING TKI THERAPY, KNOWN GENETIC ABNORMALITIES WERE NOT DETECTED. THEREAFTER, THE PATIENT UNDERWENT BONE MARROW TRANSPLANTATION FROM AN HLA 7/8 MATCHED UNRELATED DONOR (HLA-CW 1 LOCUS MISMATCH, GRAFT-VERSUS-HOST DIRECTION). THE PATIENT ACHIEVED NEUTROPHIL ENGRAFTMENT, 18 DAYS AFTER TRANSPLANTATION, LEADING TO COMPLETE REMISSION WITH AN UNDETECTABLE LEVEL OF BCR-ABL1 MRNA. THE PATIENT, HOWEVER, DIED FROM GRAFT-VERSUS-HOST DISEASE AND THROMBOTIC MICROANGIOPATHY AFTER 121 DAYS. GENE SEQUENCE ANALYSIS OF HIS CML CELL BEFORE STEM CELL TRANSPLANTATION REVEALED ASXL1 MUTATIONS. PHYSIOLOGICALLY, ASXL1 CONTRIBUTES TO EPIGENETIC REGULATION. IN THE CML-CP PATIENT IN THIS CASE REPORT, ASXL1 MUTATION CONFERRED RESISTANCE TO TKI THROUGH OBSCURE RESISTANCE MECHANISMS. EVEN THOUGH A MOLECULAR MECHANISM FOR TKI RESISTANCE IN ASXL1 MUTATION IN CML HAS REMAINED OBSCURE, EPIGENETIC MODULATION IS A PLAUSIBLE MODE OF CML DISEASE PROGRESSION. THE CLINICAL IMPACT INCLUDING PROGNOSIS OF ASXL1 FOR CML IS UNDERSCORED. AND THE TREATMENT STRATEGY OF CML WITH ASXL1 MUTATION HAS NOT BEEN ESTABLISHED. A DISCUSSION OF THIS CASE WAS EXPECTED TO FACILITATE TREATMENT OPTIONS. 2020 19 109 43 A REVIEW ON THE THERAPEUTIC ROLE OF TKIS IN CASE OF CML IN COMBINATION WITH EPIGENETIC DRUGS. CHRONIC MYELOID LEUKEMIA IS A MALIGNANCY OF BONE MARROW THAT AFFECTS WHITE BLOOD CELLS. THERE IS STRONG EVIDENCE THAT DISEASE PROGRESSION, TREATMENT RESPONSES, AND OVERALL CLINICAL OUTCOMES OF CML PATIENTS ARE INFLUENCED BY THE ACCUMULATION OF OTHER GENETIC AND EPIGENETIC ABNORMALITIES, RATHER THAN ONLY THE BCR/ABL1 ONCOPROTEIN. BOTH GENETIC AND EPIGENETIC FACTORS INFLUENCE THE EFFICACY OF CML TREATMENT STRATEGIES. TARGETED MEDICINES KNOWN AS TYROSINE-KINASE INHIBITORS HAVE DRAMATICALLY IMPROVED LONG-TERM SURVIVAL RATES IN CML PATIENTS DURING THE PREVIOUS 2 DECADES. WHEN COMPARED TO EARLIER CHEMOTHERAPY TREATMENTS, THESE DRUGS HAVE REVOLUTIONIZED CML TREATMENT AND ALLOWED MOST PEOPLE TO LIVE LONGER LIVES. ALTHOUGH EPIGENETIC INHIBITORS' ACTIVITY IS DISRUPTED IN MANY CANCERS, INCLUDING CML, BUT WHEN COMBINED WITH TKI, THEY MAY OFFER POTENTIAL THERAPEUTIC STRATEGIES FOR THE TREATMENT OF CML CELLS. THE EPIGENETICS OF TYROSINE KINASE INHIBITORS AND RESISTANCE TO THEM IS BEING STUDIED, WITH A PARTICULAR FOCUS ON IMATINIB, WHICH IS USED TO TREAT CML. IN ADDITION, THE USE OF EPIGENETIC DRUGS IN CONJUNCTION WITH TKIS HAS BEEN DISCUSSED. RESISTANCE TO TKIS IS STILL A PROBLEM IN CURING THE DISEASE, NECESSITATING THE DEVELOPMENT OF NEW THERAPIES. THIS STUDY FOCUSED ON EPIGENETIC PATHWAYS INVOLVED IN CML PATHOGENESIS AND TUMOR CELL RESISTANCE TO TKIS, BOTH OF WHICH CONTRIBUTE TO LEUKEMIC CLONE BREAKOUT AND PROLIFERATION. 2021 20 3575 36 IMPACT OF MOLECULAR PROFILING ON THE MANAGEMENT OF PATIENTS WITH MYELOFIBROSIS. MYELOFIBROSIS (MF) IS A CHRONIC MYELOPROLIFERATIVE NEOPLASM (MPN) CHARACTERIZED BY A HIGHLY HETEROGENEOUS CLINICAL COURSE, WHICH CAN BE COMPLICATED BY SEVERE CONSTITUTIONAL SYMPTOMS, MASSIVE SPLENOMEGALY, PROGRESSIVE BONE MARROW FAILURE, CARDIOVASCULAR EVENTS, AND DEVELOPMENT OF ACUTE LEUKEMIA. CONSTITUTIVE SIGNALING THROUGH THE JAK-STAT PATHWAY PLAYS A FUNDAMENTAL ROLE IN ITS PATHOGENESIS, GENERALLY DUE TO ACTIVATING MUTATIONS OF JAK2, CALR AND MPL GENES (I.E., THE MPN DRIVER MUTATIONS), PRESENT IN MOST MF PATIENTS. NEXT GENERATION SEQUENCING (NGS) PANEL TESTING HAS SHOWN THAT ADDITIONAL SOMATIC MUTATIONS CAN ALREADY BE DETECTED AT THE TIME OF DIAGNOSIS IN MORE THAN HALF OF PATIENTS, AND THAT THEY ACCUMULATE ALONG THE DISEASE COURSE. THESE MUTATIONS, MOSTLY AFFECTING EPIGENETIC MODIFIERS OR SPLICEOSOME COMPONENTS, MAY COOPERATE WITH MPN DRIVERS TO FAVOR CLONAL DOMINANCE OR INFLUENCE THE CLINICAL PHENOTYPE, AND SOME, SUCH AS HIGH MOLECULAR RISK MUTATIONS, CORRELATE WITH A MORE AGGRESSIVE CLINICAL COURSE WITH POOR TREATMENT RESPONSE. THE CURRENT MAIN ROLE OF MOLECULAR PROFILING IN CLINICAL PRACTICE IS PROGNOSTICATION, PRINCIPALLY FOR SELECTING HIGH-RISK PATIENTS WHO MAY BE CANDIDATES FOR TRANSPLANTATION, THE ONLY CURATIVE TREATMENT FOR MF TO DATE. TO THIS END, CONTEMPORARY PROGNOSTIC MODELS INCORPORATING MOLECULAR DATA ARE USEFUL TOOLS TO DISCRIMINATE DIFFERENT RISK CATEGORIES. ASIDE FROM CERTAIN CLINICAL SITUATIONS, DECISIONS REGARDING MEDICAL TREATMENT ARE NOT BASED ON PATIENT MOLECULAR PROFILING, YET THIS APPROACH MAY BECOME MORE RELEVANT IN NOVEL TREATMENT STRATEGIES, SUCH AS THE USE OF VACCINES AGAINST THE MUTANT FORMS OF JAK2 OR CALR, OR DRUGS DIRECTED AGAINST ACTIONABLE MOLECULAR TARGETS. 2022