1 3009 122 GENETICS AND EPIGENETICS IN NEOPLASMS WITH PLASMACYTOID DENDRITIC CELLS. PLASMACYTOID DENDRITIC CELLS (PDC) ARE TYPE I INTERFERON (IFN)-PRODUCING CELLS THAT PLAY A KEY ROLE IN IMMUNE RESPONSES. TWO MAJOR TYPES OF NEOPLASTIC COUNTERPARTS FOR PDC ARE NOW DISCRIMINATED: BLASTIC PDC NEOPLASM (BPDCN) AND MATURE PDC PROLIFERATION (MPDCP), ASSOCIATED WITH MYELOID NEOPLASM. TWO TYPES OF MPDCP ARE NOW BETTER DESCRIBED: CHRONIC MYELOMONOCYTIC LEUKEMIA WITH PDC EXPANSION (PDC-CMML) AND ACUTE MYELOID LEUKEMIA WITH PDC EXPANSION (PDC-AML). DIFFERENTIAL DIAGNOSIS BETWEEN PDC-AML AND BPDCN IS PARTICULARLY CHALLENGING, AND GENOMIC FEATURES CAN HELP FOR DIAGNOSIS. HERE, WE SYSTEMATICALLY REVIEW THE CYTOGENETIC, MOLECULAR, AND TRANSCRIPTIONAL CHARACTERISTICS OF BPDCN AND PDC-AML. BPDCN ARE CHARACTERIZED BY FREQUENT COMPLEX KARYOTYPES WITH RECURRENT MYB/MYC REARRANGEMENTS AS WELL AS RECURRENT DELETIONS INVOLVING ETV6, IKZF1, RB1, AND TP53 LOCI. EPIGENETIC AND SPLICING PATHWAYS ARE ALSO PARTICULARLY MUTATED, WHILE ORIGINAL PROCESSES ARE DYSREGULATED, SUCH AS NF-KB, TCF4, BCL2, AND IFN PATHWAYS; NEUTROPHIL-SPECIFIC RECEPTORS; AND CHOLINERGIC SIGNALING. IN CONTRAST, CYTOGENETIC ABNORMALITIES ARE LIMITED IN PDC-AML AND ARE QUITE SIMILAR TO OTHER AML. INTERESTINGLY, RUNX1 IS THE MOST FREQUENTLY MUTATED GENE (70% OF CASES). THESE TYPICAL GENOMIC FEATURES ARE OF POTENTIAL INTEREST FOR DIAGNOSIS, AND ALSO FROM A PROGNOSTIC OR THERAPEUTIC PERSPECTIVE. 2022 2 4556 30 MUTATIONAL SPECTRUM OF MYELOID MALIGNANCIES WITH INV(3)/T(3;3) REVEALS A PREDOMINANT INVOLVEMENT OF RAS/RTK SIGNALING PATHWAYS. MYELOID MALIGNANCIES BEARING CHROMOSOMAL INV(3)/T(3;3) ABNORMALITIES ARE AMONG THE MOST THERAPY-RESISTANT LEUKEMIAS. DEREGULATED EXPRESSION OF EVI1 IS THE MOLECULAR HALLMARK OF THIS DISEASE; HOWEVER, THE GENOME-WIDE SPECTRUM OF COOPERATING MUTATIONS IN THIS DISEASE SUBSET HAS NOT BEEN SYSTEMATICALLY ELUCIDATED. HERE, WE SHOW THAT 98% OF INV(3)/T(3;3) MYELOID MALIGNANCIES HARBOR MUTATIONS IN GENES ACTIVATING RAS/RECEPTOR TYROSINE KINASE (RTK) SIGNALING PATHWAYS. IN ADDITION, HEMIZYGOUS MUTATIONS IN GATA2, AS WELL AS HETEROZYGOUS ALTERATIONS IN RUNX1, SF3B1, AND GENES ENCODING EPIGENETIC MODIFIERS, FREQUENTLY CO-OCCUR WITH THE INV(3)/T(3;3) ABERRATION. NOTABLY, NEITHER MUTATIONAL PATTERNS NOR GENE EXPRESSION PROFILES DIFFER ACROSS INV(3)/T(3;3) ACUTE MYELOID LEUKEMIA, CHRONIC MYELOID LEUKEMIA, AND MYELODYSPLASTIC SYNDROME CASES, SUGGESTING RECOGNITION OF INV(3)/T(3;3) MYELOID MALIGNANCIES AS A SINGLE DISEASE ENTITY IRRESPECTIVE OF BLAST COUNT. THE HIGH INCIDENCE OF ACTIVATING RAS/RTK SIGNALING MUTATIONS MAY PROVIDE A TARGET FOR A RATIONAL TREATMENT STRATEGY IN THIS HIGH-RISK PATIENT GROUP. 2015 3 829 35 CHARACTERIZATION OF P190-BCR-ABL CHRONIC MYELOID LEUKEMIA REVEALS SPECIFIC SIGNALING PATHWAYS AND THERAPEUTIC TARGETS. THE ONCOGENIC PROTEIN BCR-ABL HAS TWO MAJOR ISOFORMS, P190(BCR-ABL) AND P210(BCR-ABL). WHILE P210(BCR-ABL) IS THE HALLMARK OF CHRONIC MYELOID LEUKEMIA (CML), P190(BCR-ABL) OCCURS IN THE MAJORITY OF PHILADELPHIA-POSITIVE ACUTE LYMPHOBLASTIC LEUKEMIA (PH + ALL) PATIENTS. IN CML, P190(BCR-ABL) OCCURS IN A MINORITY OF PATIENTS ASSOCIATING WITH DISTINCT HEMATOLOGICAL FEATURES AND INFERIOR OUTCOMES, YET THE PATHOGENIC ROLE OF P190(BCR-ABL) AND POTENTIAL TARGETING THERAPIES ARE LARGELY UNCHARACTERIZED. WE EMPLOYED NEXT GENERATION SEQUENCING, PHOSPHO-PROTEOMIC PROFILING, AND DRUG SENSITIVITY TESTING TO CHARACTERIZE P190(BCR-ABL) IN CML AND HEMATOPOIETIC PROGENITOR CELL LINE MODELS (BA/F3 AND HPC-LSK). P190(BCR-ABL) CML PATIENTS DEMONSTRATED POOR RESPONSE TO IMATINIB AND FREQUENT MUTATIONS IN EPIGENETIC MODIFIERS GENES. IN CONTRAST WITH P210(BCR-ABL), P190(BCR-ABL) EXHIBITED SPECIFIC TRANSCRIPTIONAL UPREGULATION OF INTERFERON, INTERLEUKIN-1 RECEPTOR, AND P53 SIGNALING PATHWAYS, ASSOCIATED WITH HYPERPHOSPHORYLATION OF RELEVANT SIGNALING MOLECULES INCLUDING JAK1/STAT1 AND PAK1 IN ADDITION TO SRC HYPERPHOSPHORYLATION. COMPARABLE TO P190(BCR-ABL) CML PATIENTS, P190(BCR-ABL) CELL LINES DEMONSTRATED SIMILAR TRANSCRIPTIONAL AND PHOSPHO-SIGNALING SIGNATURES. WITH THE DRUG SENSITIVITY SCREENING WE IDENTIFIED TARGETED DRUGS WITH SPECIFIC ACTIVITY IN P190(BCR-ABL) CELL LINES INCLUDING IAP-, PAK1-, AND SRC INHIBITORS AND GLUCOCORTICOIDS. OUR RESULTS PROVIDE NOVEL INSIGHTS INTO THE MECHANISMS UNDERLYING THE DISTINCT FEATURES OF P190(BCR-ABL) CML AND PROMISING THERAPEUTIC TARGETS FOR THIS HIGH-RISK PATIENT GROUP. 2021 4 5775 31 SPERMIDINE/SPERMINE N(1)-ACETYLTRANSFERASE ACTIVITY ASSOCIATES WITH WHITE BLOOD CELL COUNT IN MYELOID LEUKEMIAS. THE METABOLISM OF POLYAMINES, THE CATIONIC SMALL MOLECULES ESSENTIAL FOR CELL PROLIFERATION AND DIFFERENTIATION, IS ALTERED IN CANCER CELLS AND CAN BE EXPLOITED IN CANCER DIAGNOSIS AND THERAPY. SPERMIDINE/SPERMINE N(1)-ACETYLTRANSFERASE (SSAT), WHICH REGULATES INTRACELLULAR LEVELS OF POLYAMINES BY CATABOLIZING SPERMIDINE AND SPERMINE, HAS A CONTROVERSIAL ROLE IN THE DEVELOPMENT OF CANCERS. IN THIS STUDY, THE POLYAMINE METABOLISM AND FUNCTION OF SSAT WERE CHARACTERIZED IN ACUTE MYELOID LEUKEMIA (AML), CHRONIC MYELOID LEUKEMIA (CML), AND ACUTE LYMPHOID LEUKEMIA PATIENT SAMPLES. ALSO, MICE OVEREXPRESSING SSAT AND HAVING A MYELOPROLIFERATIVE PHENOTYPE WERE ANALYZED FOR THEIR RESPONSE TO DECITABINE AND HISTONE DEACETYLASE INHIBITOR TRICHOSTATIN A. THE PRESENCE OF EPIGENETIC FACTORS IN THE BONE MARROW CELLS OF SSAT MICE WAS ANALYZED. ELEVATED LEVELS OF SPERMIDINE AND SPERMINE, AS WELL AS INCREASED ACTIVITY OF SSAT, WERE DETECTED IN AML, CML, AND ACUTE LYMPHOID LEUKEMIA PATIENTS COMPARED WITH THE CONTROLS. HOWEVER, WE FOUND SSAT ACTIVITY TO BE ASSOCIATED WITH WHITE BLOOD CELL COUNT ONLY IN AML AND CML PATIENTS. DECITABINE TREATMENT BROUGHT THE PERIPHERAL BLOOD AND BONE MARROW CELL COUNTS OF SSAT MICE TO THE LEVEL OF WILD-TYPE MICE. SPERMIDINE/SPERMINE N(1)-ACETYLTRANSFERASE MICE HAD INCREASED HISTONE METHYLATION AND AN INCREASED LEVEL OF HISTONE DEACETYLASE 1 IN THEIR BONE MARROW CELLS. THE STUDY SUGGESTS THAT SSAT INFLUENCES THE DEVELOPMENT OF MYELOID MALIGNANCIES, AND EPIGENETIC FACTORS PARTLY CONTRIBUTE TO THE SSAT OVEREXPRESSION-INDUCED MYELOPROLIFERATIVE DISEASE IN MICE. 2014 5 5608 33 RUNX1-EVI1 DISRUPTS LINEAGE DETERMINATION AND THE CELL CYCLE BY INTERFERING WITH RUNX1 AND EVI1 DRIVEN GENE REGULATORY NETWORKS. HEMATOLOGICAL MALIGNANCIES ARE CHARACTERISED BY A BLOCK IN DIFFERENTIATION, WHICH IN MANY CASES IS CAUSED BY RECURRENT MUTATIONS AFFECTING THE ACTIVITY OF HEMATOPOIETIC TRANSCRIPTION FACTORS. RUNX1-EVI1 IS A FUSION PROTEIN FORMED BY THE T(3;21) TRANSLOCATION LINKING TWO TRANSCRIPTION FACTORS REQUIRED FOR NORMAL HEMATOPOIESIS. RUNX1-EVI1 EXPRESSION IS FOUND IN MYELODYSPLASTIC SYNDROME, SECONDARY ACUTE MYELOID LEUKEMIA, AND BLAST CRISIS OF CHRONIC MYELOID LEUKEMIA; WITH CLINICAL OUTCOMES BEING WORSE THAN IN PATIENTS WITH RUNX1-ETO, RUNX1 OR EVI1 MUTATIONS ALONE. RUNX1-EVI1 IS USUALLY FOUND AS A SECONDARY MUTATION, THEREFORE THE MOLECULAR MECHANISMS UNDERLYING HOW RUNX1-EVI1 ALONE CONTRIBUTES TO POOR PROGNOSIS ARE UNKNOWN. TO ADDRESS THIS QUESTION, WE INDUCED EXPRESSION OF RUNX1-EVI1 IN HEMATOPOIETIC CELLS DERIVED FROM AN EMBRYONIC STEM CELL DIFFERENTIATION MODEL. INDUCTION RESULTED IN DISRUPTION OF THE RUNX1-DEPENDENT ENDOTHELIAL-HEMATOPOIETIC TRANSITION, BLOCKED THE CELL CYCLE AND UNDERMINED CELL FATE DECISIONS IN MULTIPOTENT HEMATOPOIETIC PROGENITOR CELLS. INTEGRATIVE ANALYSES OF GENE EXPRESSION WITH CHROMATIN AND TRANSCRIPTION FACTOR BINDING DATA DEMONSTRATED THAT RUNX1-EVI1 BINDING CAUSED THE RE-DISTRIBUTION OF ENDOGENOUS RUNX1 WITHIN THE GENOME AND INTERFERED WITH BOTH RUNX1 AND EVI1 REGULATED GENE EXPRESSION PROGRAMS. IN SUMMARY, RUNX1-EVI1 EXPRESSION ALONE LEADS TO EXTENSIVE EPIGENETIC REPROGRAMMING WHICH IS INCOMPATIBLE WITH HEALTHY BLOOD PRODUCTION. 2021 6 2888 36 GAIN-OF-FUNCTION MUTATION OF GATA-2 IN ACUTE MYELOID TRANSFORMATION OF CHRONIC MYELOID LEUKEMIA. ACQUISITION OF ADDITIONAL GENETIC AND/OR EPIGENETIC ABNORMALITIES OTHER THAN THE BCR/ABL FUSION GENE IS BELIEVED TO CAUSE DISEASE PROGRESSION IN CHRONIC MYELOID LEUKEMIA (CML) FROM CHRONIC PHASE TO BLAST CRISIS (BC). TO GAIN INSIGHTS INTO THE UNDERLYING MECHANISMS OF PROGRESSION TO BC, WE SCREENED DNA SAMPLES FROM CML PATIENTS DURING BLAST TRANSFORMATION FOR MUTATIONS IN A NUMBER OF TRANSCRIPTION FACTOR GENES THAT ARE CRITICAL FOR MYELOID-LYMPHOID DEVELOPMENT. IN 85 CASES OF CML BLAST TRANSFORMATION, WE IDENTIFIED TWO NEW MUTATIONS IN THE CODING REGION OF GATA-2, A NEGATIVE REGULATOR OF HEMATOPOIETIC STEM/PROGENITOR CELL DIFFERENTIATION. A L359V SUBSTITUTION WITHIN ZINC FINGER DOMAIN (ZF) 2 OF GATA-2 WAS FOUND IN EIGHT CASES WITH MYELOMONOBLASTIC FEATURES, WHEREAS AN IN-FRAME DELETION OF 6 AA (DELTA341-346) SPANNING THE C-TERMINAL BORDER OF ZF1 WAS DETECTED IN ONE PATIENT AT MYELOID BC WITH EOSINOPHILIA. FURTHER STUDIES INDICATED THAT L359V NOT ONLY INCREASED TRANSACTIVATION ACTIVITY OF GATA-2 BUT ALSO ENHANCED ITS INHIBITORY EFFECTS ON THE ACTIVITY OF PU.1, A MAJOR REGULATOR OF MYELOPOIESIS. CONSISTENT WITH THE MYELOMONOBLASTIC FEATURES OF CML TRANSFORMATION WITH THE GATA-2 L359V MUTANT, TRANSDUCTION OF THE GATA-2 L359V MUTANT INTO HL-60 CELLS OR BCR/ABL-HARBORING MURINE CELLS DISTURBED MYELOMONOCYTIC DIFFERENTIATION/PROLIFERATION IN VITRO AND IN VIVO, RESPECTIVELY. THESE DATA STRONGLY SUGGEST THAT GATA-2 MUTATIONS MAY PLAY A ROLE IN ACUTE MYELOID TRANSFORMATION IN A SUBSET OF CML PATIENTS. 2008 7 5511 28 RIBONUCLEASES IN TUMOR GROWTH. THIS REVIEW SUMMARIZES DATA ON AMBIGUOUS BIOLOGICAL FUNCTIONS OF RIBONUCLEASES (RNASES) AT TUMOR GROWTH. IN SOME CASES THE RAISED LEVEL OF ENZYME ACTIVITY IN BIOLOGICAL FLUIDS CAN BE REGARDED AS AN ADDITIONAL MARKER OF MALIGNANT GROWTH (PANCREAS CANCER, CHRONIC MYELOID LEUKEMIA, ETC.). AT THE SAME TIME THE ACTIVITY OF RNASES IS OFTEN LOWERED IN TUMOR TISSUE. HIGH SUBSTRATE SPECIFICITY OF PARTICULAR RNASES PROVIDES METABOLIC BALANCE BETWEEN VARIOUS KINDS OF RNAS WITH VARIOUS HALF-TIME EXCHANGE TURN. RNASES ARE THE IMPORTANT FACTORS OF EPIGENETIC REGULATION OF GENE ACTIVITY IN CELLS. THE ACTIVITY OF RNASES IS ADJUSTABLE BY INHIBITORS AND OTHER FACTORS, AND DEFINES TIME OF EXISTENCE OF DIFFERENT KINDS OF RNAS. RNASES (THE MODIFIED VARIANTS OF RNASE A, RNASES OF SEMEN FLUID OF THE CATTLE, RNASE OF AMPHIBIA OOCYTES) CAN BE USED AS ANTI-TUMOR THERAPEUTIC AGENTS. ON THE OTHER HAND, SOME INHIBITORS OF RNASES OF NATURAL OR SYNTHETIC ORIGIN WERE DEMONSTRATED TO BE PERSPECTIVE DRUGS THAT INHIBIT TUMOR GROWTH. 2009 8 5934 26 TARGETING FEATURES OF CURAXIN CBL0137 ON HEMATOLOGICAL MALIGNANCIES IN VITRO AND IN VIVO. THE ANTICANCER ACTIVITY OF CURAXIN CBL0137, A DNA-BINDING SMALL MOLECULE WITH CHROMATIN REMODULATING EFFECT, HAS BEEN DEMONSTRATED IN DIFFERENT CANCERS. HEREIN, A COMPARATIVE EVALUATION OF CBL0137 ACTIVITY WAS PERFORMED IN RESPECT TO ACUTE MYELOID LEUKEMIA (AML), ACUTE LYMPHOBLASTIC LEUKEMIA (ALL), CHRONIC MYELOID LEUKEMIA AND MULTIPLE MYELOMA (MM) CULTURED IN VITRO. MTT ASSAY SHOWED AML AND MM HIGHER SENSITIVITY TO CBL0137'S CYTOSTATIC EFFECT COMPARATIVELY TO OTHER HEMATOLOGICAL MALIGNANCY CELLS. FLOW CYTOMETRY CELL CYCLE ANALYSIS REVEALED AN INCREASE IN SUBG1 AND G2/M POPULATIONS AFTER CBL0137 CELL TREATMENT, BUT THE PREVALENT TYPE OF ARREST VARIED. APOPTOSIS ACTIVATION BY CBL0137 MEASURED BY ANNEXIN-V/PI DUAL STAINING WAS MORE ACTIVE IN AML AND MM CELLS. RT2 PCR ARRAY SHOWED THAT CHANGES CAUSED BY CBL0137 IN SIGNALING PATHWAYS INVOLVED IN CANCER PATHOGENESIS WERE MORE INTENSIVE IN AML AND MM CELLS. ON THE MURINE MODEL OF AML WEHI-3, CBL0137 SHOWED SIGNIFICANT ANTICANCER EFFECTS IN VIVO, WHICH WERE EVALUATED BY CORRESPONDING CHANGES IN SPLEEN AND LIVER. THUS, MORE PRONOUNCED ANTICANCER EFFECTS OF CBL0137 IN VITRO WERE OBSERVED IN RESPECT TO AML AND MM. EXPERIMENTS IN VIVO ALSO INDICATED THE PERSPECTIVE OF CBL0137 USE FOR AML TREATMENT. THIS IN ACCORDANCE WITH THE FRONTLINE TREATMENT APPROACH IN AML USING EPIGENETIC DRUGS. 2023 9 2974 24 GENETIC AND METHYLATION STATUS OF CDKN2A (P14(ARF)/P16(INK4A)) AND TP53 GENES IN RECURRENT RESPIRATORY PAPILLOMATOSIS. RECURRENT RESPIRATORY PAPILLOMATOSIS (RRP) IS A RARE AND CHRONIC DISEASE AFFECTING THE UPPER AIRWAY WITH PAPILLOMATOUS LESIONS CAUSED BY THE HUMAN PAPILLOMAVIRUS (HPV) INFECTION, ESPECIALLY HPV-6 AND/OR HPV-11 TYPES. LITTLE IS KNOWN ABOUT THE GENETIC AND EPIGENETIC DRIVERS IN RRP PATHOPHYSIOLOGY. FOR THIS PURPOSE, WE ANALYZED 27 PAPILLOMATOUS LESIONS FROM PATIENTS WITH RRP TO EVALUATE SOMATIC MUTATIONS AND METHYLATION STATUS IN CDKN2A (P14(ARF)/P16(INK4A)) AND TP53, WHICH ARE KEY TUMOR SUPPRESSOR GENES FOR THE CELL CYCLE CONTROL. SANGER SEQUENCING ANALYSIS REVEALED ONE SOMATIC MUTATION IN TP53 (C.733_734INSA) AND FOUR MUTATIONS IN CDKN2A (C.-30G > T, C.29_30INSA, C.69DELT, AND C.300C > A). THESE MUTATIONS WERE OBSERVED IN 10 PATIENTS, 6 OF WHICH CARRIED DOUBLE MUTATION. FURTHERMORE, 50% (5/10) OF THESE PATIENTS CARRYING SOMATIC MUTATIONS HAD RRP SEVERITY, REPRESENTING 62.5% (5/8) OF THE SEVERITY CASES IN THIS STUDY, ALBEIT NO SIGNIFICANT ASSOCIATION WAS FOUND BETWEEN SOMATIC MUTATIONS AND DISEASE SEVERITY. METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION ASSAYS REVEALED P14(ARF) PROMOTER HYPERMETHYLATION IN 100% OF CASES, FOLLOWED BY TP53 (96.3%) AND P16(INK4A) (55.6%), SUGGESTING THE INFLUENCE OF HPV IN THE DNA METHYLATION MACHINERY. IN CONCLUSION, SOMATIC MUTATIONS WERE NOT COMMON EVENTS IDENTIFIED IN PATIENTS WITH RRP. HOWEVER, EPIGENETIC MODULATION BY HIGH METHYLATION RATES, PARTICULARLY FOR THE P14(ARF)/TP53 PATHWAY, SEEMS TO BE IN THE COURSE OF RRP DEVELOPMENT. 2022 10 1843 25 EFFECTS OF TELOMERASE INHIBITOR ON EPIGENETIC CHROMATIN MODIFICATION ENZYMES IN MALIGNANCIES. TELOMERASE HAS A CRITICAL ROLE IN CELL PROLIFERATION, TUMOR MAINTAINING, AND THERAPY RESISTANCE, WHICH ACT BY MODIFYING MANY SIGNALING PATHWAYS. 2-[(E)-3-NAPHTALEN-2-YL-BUT-2-ENOYLAMINO]-BENZOIC ACID (BIBR1532) IS ONE OF THE MOST STUDIED TELOMERASE INHIBITORS, AND IT TARGETS TELOMERASE COMPONENTS TERC AND TERT. IN THIS NOVEL STUDY, WE AIMED TO INVESTIGATE THE EPIGENETIC EFFECTS OF BIBR1532 ON BOTH HEMATOLOGIC MALIGNANCIES AND SOLID TUMORS. K-562 HUMAN CHRONIC MYELOID LEUKEMIA CELL LINE AND U87MG GLIOBLASTOMA CELL LINE WERE COMPARED WITH CONTROL GROUPS WITHOUT BIBR1532 TREATMENT. CYTOTOXIC EFFECTS OF BIBR1532 WERE DETERMINED BY USING WST-1 ASSAY. APOPTOTIC EFFECTS OF BIBR1532 WERE DETECTED BY USING ANNEXIN V METHOD. TO ASSESS EXPRESSION CHANGES IN THE HUMAN EPIGENETIC CHROMATIN MODIFICATION ENZYME GENES, TOTAL RNA WAS ISOLATED FROM K-562 AND U87MG CELLS TREATED WITH BIBR1532 AND UNTREATED CONTROL CELLS. BIBR1532 INDUCED 2.41-FOLD APOPTOTIC CELL DEATH IN U87MG CELL LINES COMPARED WITH CONTROL GROUPS. APOPTOSIS WAS SLIGHTLY INDUCED IN K-562 CELLS WITH BIBR1532 TREATMENT COMPARED WITH CONTROL CELLS. WE OBSERVED THAT BIBR1532 ALSO REGULATES SIMILAR GENES IN BOTH CELL LINES, AND IT IS USEFUL ON EPIGENETIC MECHANISMS. AS A RESULT, TELOMERASE INHIBITOR BIBR1532 HAS A SIGNIFICANT EFFECT ON BOTH HEMATOLOGICAL MALIGNANCIES AND SOLID TUMORS. 2018 11 2763 24 EXPRESSION OF THE LEUKEMIC PROGNOSTIC MARKER CD7 IS LINKED TO EPIGENETIC MODIFICATIONS IN CHRONIC MYELOID LEUKEMIA. BACKGROUND: EXPRESSION LEVELS OF THE CELL SURFACE GLYCOPROTEIN, CD7, AND THE SERINE PROTEASE, ELASTASE 2 (ELA2), IN THE LEUKEMIC CELLS OF PATIENTS WITH CHRONIC MYELOID LEUKEMIA (CML) HAVE BEEN ASSOCIATED WITH CLINICAL OUTCOME. HOWEVER, LITTLE IS KNOWN ABOUT THE MECHANISMS THAT UNDERLIE THE VARIABLE EXPRESSION OF THESE GENES IN THE LEUKEMIC CELLS. RESULTS: TO ADDRESS THIS QUESTION, WE COMPARED THE LEVEL OF THEIR EXPRESSION WITH THE DNA METHYLATION AND HISTONE ACETYLATION STATUS OF 5' SEQUENCES OF BOTH GENES IN LEUKEMIC CELL LINES AND PRIMITIVE (LIN-CD34+) LEUKEMIC CELLS FROM CHRONIC PHASE CML PATIENTS. DNA METHYLATION OF THE ELA2 GENE PROMOTER DID NOT CORRELATE WITH ITS EXPRESSION PATTERN IN LIN-CD34+ CELLS FROM CHRONIC PHASE CML PATIENT SAMPLES EVEN THOUGH THERE WAS CLEAR DIFFERENTIAL DNA METHYLATION OF THIS LOCUS IN ELA2-EXPRESSING AND NON-EXPRESSING CELL LINES. IN CONTRAST, WE FOUND A STRONG RELATION BETWEEN CD7 EXPRESSION AND TRANSCRIPTION-PERMISSIVE CHROMATIN MODIFICATIONS, BOTH AT THE LEVEL OF DNA METHYLATION AND HISTONE ACETYLATION WITH EVIDENCE OF HYPOMETHYLATION OF THE CD7 PROMOTER REGION IN THE LIN-CD34+ CELLS FROM CML PATIENTS WITH HIGH CD7 EXPRESSION. CONCLUSION: THESE FINDINGS INDICATE A LINK BETWEEN EPIGENETIC MODIFICATIONS AND CD7 EXPRESSION IN PRIMITIVE CML CELLS. 2010 12 3898 28 LARGE-SCALE TOPOLOGICAL DISRUPTION OF CHROMOSOME TERRITORIES 9 AND 22 IS ASSOCIATED WITH NONRESPONSE TO TREATMENT IN CML. CHRONIC MYELOID LEUKEMIA (CML) IS A MYELOPROLIFERATIVE NEOPLASM DEFINED BY THE PRESENCE OF T(9;22) TRANSLOCATION WHOSE ORIGIN HAS BEEN ASSOCIATED WITH THE TRIDIMENSIONAL GENOME ORGANIZATION. THIS REARRANGEMENT LEADS TO THE FUSION OF BCR AND ABL1 GENES GIVING RISE TO A CHIMERIC PROTEIN WITH CONSTITUTIVE KINASE ACTIVITY. IMATINIB, A TYROSINE KINASE INHIBITOR (TKI), IS USED AS A FIRST-LINE TREATMENT FOR CML, THOUGH ~40% OF CML PATIENTS DO NOT RESPOND. HERE, USING STRUCTURED ILLUMINATION MICROSCOPY (SIM) AND 3D RECONSTRUCTION, WE STUDIED THE 3D ORGANIZATION PATTERNS OF THE ABL1 AND BCR GENES, AND THEIR CHROMOSOME TERRITORIES (CTS) CT9 AND CT22, IN CD34+ CELLS FROM CML PATIENTS THAT RESPONDED OR NOT TO TKI. WE FOUND THAT TKI RESISTANCE IN CML IS ASSOCIATED WITH HIGH LEVELS OF STRUCTURAL DISRUPTION OF CT9 AND CT22 IN CD34+ CELLS, INCREASED CT VOLUMES (ESPECIALLY FOR CT22), INTERMINGLING BETWEEN CT9 AND CT22, AND AN OPEN-CHROMATIN EPIGENETIC MARK IN CT22. ALTOGETHER OUR RESULTS SUGGEST THAT LARGE-SCALE DISRUPTION OF CT9 AND CT22 CORRELATES WITH THE CLINICAL RESPONSE OF CML PATIENTS, WHICH COULD BE TRANSLATED INTO A POTENTIAL PROGNOSTIC MARKER OF RESPONSE TO TREATMENT IN THIS DISEASE AND PROVIDE NOVEL INSIGHTS INTO THE MECHANISMS UNDERLYING RESISTANCE TO TKI IN CML. 2022 13 768 33 CD47 (CLUSTER OF DIFFERENTIATION 47). CD47, ALSO KNOWN AS INTEGRIN-ASSOCIATED PROTEIN, IS A CONSTITUTIVELY AND UBIQUITOUSLY EXPRESSED TRANSMEMBRANE RECEPTOR. CD47 IS CONSERVED ACROSS AMNIOTES INCLUDING MAMMALS, REPTILES, AND BIRDS. EXPRESSION IS INCREASED IN MANY CANCERS AND, IN NON-MALIGNANT CELLS, BY STRESS AND WITH AGING. THE UP-REGULATION OF CD47 EXPRESSION IS GENERALLY EPIGENETIC, WHEREAS GENE AMPLIFICATION OCCURS WITH LOW FREQUENCY IN SOME CANCERS. CD47 IS A HIGH AFFINITY SIGNALING RECEPTOR FOR THE SECRETED PROTEIN THROMBOSPONDIN-1 (THBS1) AND THE COUNTER-RECEPTOR FOR SIGNAL REGULATORY PROTEIN-ALPHA (SIRPA, SIRPALPHA) AND SIRPGAMMA (SIRPG). CD47 INTERACTION WITH SIRPALPHA SERVES AS A MARKER OF SELF TO INNATE IMMUNE CELLS AND THEREBY PROTECTS CANCER CELLS FROM PHAGOCYTIC CLEARANCE. CONSEQUENTLY, HIGHER CD47 CORRELATES WITH A POOR PROGNOSIS IN SOME CANCERS, AND THERAPEUTIC BLOCKADE CAN SUPPRESS TUMOR GROWTH BY ENHANCING INNATE ANTITUMOR IMMUNITY. CD47 EXPRESSED ON CYTOTOXIC T CELLS, DENDRITIC CELLS, AND NK CELLS MEDIATES INHIBITORY THBS1 SIGNALING THAT FURTHER LIMITS ANTITUMOR IMMUNITY. CD47 LATERALLY ASSOCIATES WITH SEVERAL INTEGRINS AND THEREBY REGULATES CELL ADHESION AND MIGRATION. CD47 HAS ADDITIONAL LATERAL BINDING PARTNERS IN SPECIFIC CELL TYPES, AND LIGATION OF CD47 IN SOME CASES MODULATES THEIR FUNCTION. THBS1-CD47 SIGNALING IN NON-MALIGNANT CELLS INHIBITS NITRIC OXIDE/CGMP, CALCIUM, AND VEGF SIGNALING, MITOCHONDRIAL HOMEOSTASIS, STEM CELL MAINTENANCE, PROTECTIVE AUTOPHAGY, AND DNA DAMAGE RESPONSE, AND PROMOTES NADPH OXIDASE ACTIVITY. CD47 SIGNALING IS A PHYSIOLOGICAL REGULATOR OF PLATELET ACTIVATION, ANGIOGENESIS AND BLOOD FLOW. THBS1/CD47 SIGNALING IS FREQUENTLY DYSREGULATED IN CHRONIC DISEASES. 2021 14 3484 31 IDENTIFICATION OF CHROMATIN REMODELING GENES ARID4A AND ARID4B AS LEUKEMIA SUPPRESSOR GENES. BACKGROUND: LEUKEMIA EVOLVES THROUGH A MULTISTEP PROCESS FROM PREMALIGNANCY TO MALIGNANCY. EPIGENETIC ALTERATIONS, INCLUDING HISTONE MODIFICATIONS, HAVE BEEN PROPOSED TO PLAY AN IMPORTANT ROLE IN TUMORIGENESIS. THE INVOLVEMENT OF TWO CHROMATIN REMODELING GENES, RETINOBLASTOMA-BINDING PROTEIN 1 (RBBP1/ARID4A) AND RBBP1-LIKE 1 (RBBP1L1/ARID4B), IN LEUKEMOGENESIS WAS NOT CHARACTERIZED. METHODS: THE LEUKEMIC PHENOTYPE OF MICE DEFICIENT FOR ARID4A WITH OR WITHOUT HAPLOINSUFFICIENCY FOR ARID4B WAS INVESTIGATED BY SERIALLY MONITORING COMPLETE BLOOD COUNTS TOGETHER WITH MICROSCOPIC HISTOLOGIC ANALYSIS AND FLOW CYTOMETRIC ANALYSIS OF BONE MARROW AND SPLEEN FROM THE ARID4A(-/-) MICE OR ARID4A(-/-)ARID4B(+/-) MICE. REGULATION IN BONE MARROW CELLS OF DOWNSTREAM GENES IMPORTANT FOR NORMAL HEMATOPOIESIS WAS ANALYZED BY REVERSE TRANSCRIPTION-POLYMERASE CHAIN REACTION. GENOTYPIC EFFECTS ON HISTONE MODIFICATIONS WERE EXAMINED BY WESTERN BLOTTING AND IMMUNOFLUORESCENCE ANALYSIS. ALL STATISTICAL TESTS WERE TWO-SIDED. RESULTS: YOUNG (2-5 MONTHS OLD) ARID4A-DEFICIENT MICE HAD INEFFECTIVE BLOOD CELL PRODUCTION IN ALL HEMATOPOIETIC LINEAGES. BEYOND 5 MONTHS OF AGE, THE ARID4A(-/-) MICE MANIFESTED MONOCYTOSIS, ACCOMPANIED BY SEVERE ANEMIA AND THROMBOCYTOPENIA. THESE SICK ARID4A(-/-) MICE SHOWED BONE MARROW FAILURE WITH MYELOFIBROSIS ASSOCIATED WITH SPLENOMEGALY AND HEPATOMEGALY. FIVE OF 42 ARID4A(-/-) MICE AND 10 OF 12 ARID4A(-/-)ARID4B(+/-) MICE PROGRESSED TO ACUTE MYELOID LEUKEMIA (AML) AND HAD RAPID FURTHER INCREASES OF LEUKOCYTE COUNTS. EXPRESSION OF HOX GENES (HOXB3, HOXB5, HOXB6, AND HOXB8) WAS DECREASED IN ARID4A-DEFICIENT BONE MARROW CELLS WITH OR WITHOUT ARID4B HAPLOINSUFFICIENCY, AND FOXP3 EXPRESSION WAS REDUCED IN ARID4A(-/-)ARID4B(+/-) BONE MARROW. INCREASES OF HISTONE TRIMETHYLATION OF H3K4, H3K9, AND H4K20 (FOLD INCREASES IN TRIMETHYLATION = 32, 95% CONFIDENCE INTERVAL [CI] = 27 TO 32; 45, 95% CI = 41 TO 49; AND 2.2, 95% CI = 1.7 TO 2.7, RESPECTIVELY) WERE OBSERVED IN THE BONE MARROW OF ARID4A-DEFICIENT MICE. CONCLUSIONS: ARID4A-DEFICIENT MICE INITIALLY DISPLAY INEFFECTIVE HEMATOPOIESIS, FOLLOWED BY TRANSITION TO CHRONIC MYELOMONOCYTIC LEUKEMIA (CMML)-LIKE MYELODYSPLASTIC/MYELOPROLIFERATIVE DISORDER, AND THEN TRANSFORMATION TO AML. THE DISEASE PROCESSES IN THE ARID4A-DEFICIENT MICE ARE VERY SIMILAR TO THE COURSE OF EVENTS IN HUMANS WITH CMML AND AML. THIS MOUSE MODEL HAS THE POTENTIAL TO FURNISH ADDITIONAL INSIGHTS INTO THE ROLE OF EPIGENETIC ALTERATIONS IN LEUKEMOGENESIS, AND IT MAY BE USEFUL IN DEVELOPING NOVEL PHARMACOLOGICAL APPROACHES TO TREATMENT OF PRELEUKEMIC AND LEUKEMIC STATES. 2008 15 62 24 A HIGH DEFINITION PICTURE OF SOMATIC MUTATIONS IN CHRONIC LYMPHOPROLIFERATIVE DISORDER OF NATURAL KILLER CELLS. THE MOLECULAR PATHOGENESIS OF CHRONIC LYMPHOPROLIFERATIVE DISORDER OF NATURAL KILLER (NK) CELLS (CLPD-NK) IS POORLY UNDERSTOOD. FOLLOWING THE SCREENING OF 57 CLPD-NK PATIENTS, ONLY FIVE PRESENTED STAT3 MUTATIONS. WES PROFILING OF 13 CASES NEGATIVE FOR STAT3/STAT5B MUTATIONS UNCOVERED AN AVERAGE OF 18 CLONAL, POPULATION RARE AND DELETERIOUS SOMATIC VARIANTS PER PATIENT. THE MUTATIONAL LANDSCAPE OF CLPD-NK SHOWED THAT MOST PATIENTS CARRY A HEAVY MUTATIONAL BURDEN, WITH MAJOR AND SUBCLONAL DELETERIOUS MUTATIONS CO-EXISTING IN THE LEUKEMIC CLONE. SOMATIC MUTATIONS HIT GENES WIRED TO CANCER PROLIFERATION, SURVIVAL, AND MIGRATION PATHWAYS, IN THE FIRST PLACE RAS/MAPK, PI3K-AKT, IN ADDITION TO JAK/STAT (PIK3R1 AND PTK2). WE CONFIRMED VARIANTS WITH PUTATIVE DRIVER ROLE OF MAP10, MPZL1, RPS6KA1, SETD1B, TAOK2, TMEM127, AND TNFRSF1A GENES, AND OF GENES LINKED TO VIRAL INFECTIONS (DDX3X AND RSF1) AND DNA REPAIR (PAXIP1). A TRUNCATING MUTATION OF THE EPIGENETIC REGULATOR TET2 AND A VARIANT LIKELY ABROGATING PIK3R1-NEGATIVE REGULATORY ACTIVITY WERE VALIDATED. THIS STUDY SIGNIFICANTLY FURTHERED THE VIEW OF THE GENES AND PATHWAYS INVOLVED IN CLPD-NK, INDICATED SIMILARITIES WITH AGGRESSIVE DISEASES OF NK CELLS AND DETECTED MUTATED GENES TARGETABLE BY APPROVED DRUGS, BEING A STEP FORWARD TO PERSONALIZED PRECISION MEDICINE FOR CLPD-NK PATIENTS. 2020 16 2867 24 FUNCTIONAL AND CANCER GENOMICS OF ASXL FAMILY MEMBERS. ADDITIONAL SEX COMBS-LIKE (ASXL)1, ASXL2 AND ASXL3 ARE HUMAN HOMOLOGUES OF THE DROSOPHILA ASX GENE THAT ARE INVOLVED IN THE REGULATION OR RECRUITMENT OF THE POLYCOMB-GROUP REPRESSOR COMPLEX (PRC) AND TRITHORAX-GROUP (TRXG) ACTIVATOR COMPLEX. ASXL PROTEINS CONSIST OF ASXN, ASXH, ASXM1, ASXM2 AND PHD DOMAINS. ASXL1 DIRECTLY INTERACTS WITH BAP1, KDM1A (LSD1), NCOA1 AND NUCLEAR HORMONE RECEPTORS (NHRS), SUCH AS RETINOIC ACID RECEPTORS, OESTROGEN RECEPTOR AND ANDROGEN RECEPTOR. ASXL FAMILY MEMBERS ARE EPIGENETIC SCAFFOLDING PROTEINS THAT ASSEMBLE EPIGENETIC REGULATORS AND TRANSCRIPTION FACTORS TO SPECIFIC GENOMIC LOCI WITH HISTONE MODIFICATIONS. ASXL1 IS INVOLVED IN TRANSCRIPTIONAL REPRESSION THROUGH AN INTERACTION WITH PRC2 AND ALSO CONTRIBUTES TO TRANSCRIPTIONAL REGULATION THROUGH INTERACTIONS WITH BAP1 AND/OR NHR COMPLEXES. GERM-LINE MUTATIONS OF HUMAN ASXL1 AND ASXL3 OCCUR IN BOHRING-OPITZ AND RELATED SYNDROMES. AMPLIFICATION AND OVEREXPRESSION OF ASXL1 OCCUR IN CERVICAL CANCER. TRUNCATION MUTATIONS OF ASXL1 OCCUR IN COLORECTAL CANCERS WITH MICROSATELLITE INSTABILITY (MSI), MALIGNANT MYELOID DISEASES, CHRONIC LYMPHOCYTIC LEUKAEMIA, HEAD AND NECK SQUAMOUS CELL CARCINOMA, AND LIVER, PROSTATE AND BREAST CANCERS; THOSE OF ASXL2 OCCUR IN PROSTATE CANCER, PANCREATIC CANCER AND BREAST CANCER AND THOSE OF ASXL3 ARE OBSERVED IN MELANOMA. EPC1-ASXL2 GENE FUSION OCCURS IN ADULT T-CELL LEUKAEMIA/LYMPHOMA. THE PROGNOSIS OF MYELOID MALIGNANCIES WITH MISREGULATING TRUNCATION MUTATIONS OF ASXL1 IS POOR. ASXL FAMILY MEMBERS ARE ASSUMED TO BE TUMOUR SUPPRESSIVE OR ONCOGENIC IN A CONTEXT-DEPENDENT MANNER. 2013 17 5640 29 SERUM TUMOR MARKERS AND MOLECULAR BIOLOGICAL DIAGNOSIS IN PANCREATIC CANCER. RECENT STUDIES ON GENETIC ABNORMALITIES IN PANCREATIC DUCTAL CANCER HAVE LED TO THE INVESTIGATION OF TUMOR MARKERS AND GENETIC MARKERS IN BOTH SERUM AND PANCREATIC JUICE (PJ). SERUM TYPE 1 CHAIN CARBOHYDRATE ANTIGENS SUCH AS CA19-9 ARE POSITIVE IN NEARLY 80% OF PATIENTS WITH PANCREATIC CANCER (PCA), OF WHICH MOST ARE IN ADVANCED STAGE, WHEREAS FALSE-POSITIVE RATES ARE RELATIVELY HIGH AT 20%-30% IN BENIGN HEPATOBILIARY AND PANCREATIC DISEASES. ALTHOUGH THE PREVALENCE OF TYPE 2 CHAIN CARBOHYDRATE ANTIGENS, SUCH AS SLX, IS RELATIVELY LOW, CANCER SPECIFICITY OF THESE ANTIGENS IS HIGH. HOWEVER, SERUM TUMOR MARKERS HAVE LIMITED DIAGNOSTIC VALUE FOR EARLY DETECTION OF PCA. IN PJ COLLECTED ENDOSCOPICALLY FROM PATIENTS WITH PCA, K-RAS MUTATIONS (KRM) ARE DETECTABLE IN > 80%, WHEREAS KRM ARE OBSERVED IN 20%-30% OF PJ FROM PATIENTS WITH CHRONIC PANCREATITIS (CP), REFLECTING BENIGN MUCOUS CELL HYPERPLASIA HARBORING KRM. THUS, A QUALITATIVE ANALYSIS OF KRM IN PJ IS UNSUITABLE FOR DIAGNOSIS OF PCA. ON THE OTHER HAND, USING AN HYBRIDIZATION PROTECTION ASSAY THAT CAN QUANTITATIVELY DETERMINE KRM, KRM WERE POSITIVE IN 66% OF PCA BUT ONLY IN 40% OF CP CASES, INDICATING THAT QUALITATIVE ANALYSIS OF KRM IN PJ MAY BE USEFUL FOR DIFFERENTIATING PCA FROM CP. P53 MUTATIONS ARE FOUND IN 4%-50% IN PJ FROM PATIENTS WITH PCA BUT ARE NOT DETECTABLE IN PJ FROM CP, SUGGESTING THAT THE SPECIFICITY OF P53 MUTATIONS IS VERY HIGH FOR PCA. FURTHERMORE, P53 MUTATIONS WERE DETECTED IN 7 OF 15 (47%) PATIENTS WITH PCA IN WHICH THE PJ CYTOLOGIC DIAGNOSIS WAS NEGATIVE. TELOMERASE (TE) ACTIVITY OR ITS CATALYTIC SUBUNIT, H-TERT, WAS REPORTEDLY POSITIVE >80% IN PJ FROM PCA BUT WAS DETECTED IN <20% OF PJ FROM CP. TE ACTIVITY IN PJ FROM CP ORIGINATES FROM LYMPHOCYTES. THE DEVELOPMENT AND APPLICATION OF THESE NEW GENETIC AND EPIGENETIC MARKERS WITH HIGH SPECIFICITY AND SENSITIVITY FOR PCA IN SERUM AND PJ WILL SIGNIFICANTLY IMPROVE OUR DIAGNOSTIC ACCURACY. 2004 18 2696 29 EWING SARCOMA. EWING SARCOMA IS THE SECOND MOST FREQUENT BONE TUMOUR OF CHILDHOOD AND ADOLESCENCE THAT CAN ALSO ARISE IN SOFT TISSUE. EWING SARCOMA IS A HIGHLY AGGRESSIVE CANCER, WITH A SURVIVAL OF 70-80% FOR PATIENTS WITH STANDARD-RISK AND LOCALIZED DISEASE AND ~30% FOR THOSE WITH METASTATIC DISEASE. TREATMENT COMPRISES LOCAL SURGERY, RADIOTHERAPY AND POLYCHEMOTHERAPY, WHICH ARE ASSOCIATED WITH ACUTE AND CHRONIC ADVERSE EFFECTS THAT MAY COMPROMISE QUALITY OF LIFE IN SURVIVORS. HISTOLOGICALLY, EWING SARCOMAS ARE COMPOSED OF SMALL ROUND CELLS EXPRESSING HIGH LEVELS OF CD99. GENETICALLY, THEY ARE CHARACTERIZED BY BALANCED CHROMOSOMAL TRANSLOCATIONS IN WHICH A MEMBER OF THE FET GENE FAMILY IS FUSED WITH AN ETS TRANSCRIPTION FACTOR, WITH THE MOST COMMON FUSION BEING EWSR1-FLI1 (85% OF CASES). EWING SARCOMA BREAKPOINT REGION 1 PROTEIN (EWSR1)-FRIEND LEUKAEMIA INTEGRATION 1 TRANSCRIPTION FACTOR (FLI1) IS A TUMOUR-SPECIFIC CHIMERIC TRANSCRIPTION FACTOR (EWSR1-FLI1) WITH NEOMORPHIC EFFECTS THAT MASSIVELY REWIRES THE TRANSCRIPTOME. ADDITIONALLY, EWSR1-FLI1 REPROGRAMMES THE EPIGENOME BY INDUCING DE NOVO ENHANCERS AT GGAA MICROSATELLITES AND BY ALTERING THE STATE OF GENE REGULATORY ELEMENTS, CREATING A UNIQUE EPIGENETIC SIGNATURE. ADDITIONAL MUTATIONS AT DIAGNOSIS ARE RARE AND MAINLY INVOLVE STAG2, TP53 AND CDKN2A DELETIONS. EMERGING STUDIES ON THE MOLECULAR MECHANISMS OF EWING SARCOMA HOLD PROMISE FOR IMPROVEMENTS IN EARLY DETECTION, DISEASE MONITORING, LOWER TREATMENT-RELATED TOXICITY, OVERALL SURVIVAL AND QUALITY OF LIFE. 2018 19 4867 26 OSSIFYING FIBROMA TUMOR STEM CELLS ARE MAINTAINED BY EPIGENETIC REGULATION OF A TSP1/TGF-BETA/SMAD3 AUTOCRINE LOOP. ABNORMAL STEM CELL FUNCTION MAKES A KNOWN CONTRIBUTION TO MANY MALIGNANT TUMORS, BUT THE ROLE OF STEM CELLS IN BENIGN TUMORS IS NOT WELL UNDERSTOOD. HERE, WE SHOW THAT OSSIFYING FIBROMA (OF) CONTAINS A STEM CELL POPULATION THAT RESEMBLES MESENCHYMAL STEM CELLS (OFMSCS) AND IS CAPABLE OF GENERATING OF-LIKE TUMOR XENOGRAFTS. MECHANISTICALLY, OFMSCS SHOW ENHANCED TGF-BETA SIGNALING THAT INDUCES ABERRANT PROLIFERATION AND DEFICIENT OSTEOGENESIS VIA NOTCH AND BMP SIGNALING PATHWAYS, RESPECTIVELY. THE ELEVATED TGF-BETA ACTIVITY IS TIGHTLY REGULATED BY JHDM1D-MEDIATED EPIGENETIC REGULATION OF THROMBOSPONDIN-1 (TSP1), FORMING A JHDM1D/TSP1/TGF-BETA/SMAD3 AUTOCRINE LOOP. INHIBITION OF TGF-BETA SIGNALING IN OFMSCS CAN RESCUE THEIR ABNORMAL OSTEOGENIC DIFFERENTIATION AND ELEVATED PROLIFERATION RATE. FURTHERMORE, CHRONIC ACTIVATION OF TGF-BETA CAN CONVERT NORMAL MSCS INTO OF-LIKE MSCS VIA ESTABLISHMENT OF THIS JHDM1D/TSP1/TGF-BETA/SMAD3 AUTOCRINE LOOP. THESE RESULTS REVEAL THAT EPIGENETIC REGULATION OF TGF-BETA SIGNALING IN MSCS GOVERNS THE BENIGN TUMOR PHENOTYPE IN OF AND HIGHLIGHT TGF-BETA SIGNALING AS A CANDIDATE THERAPEUTIC TARGET. 2013 20 2818 16 FIBROSIS UNDER ARREST. APPROXIMATELY 5% OF PEOPLE THAT ARE HOSPITALIZED FOR ANY REASON DEVELOP ACUTE KIDNEY FAILURE, WHICH, IN SOME CASES, PROGRESSES TO A CHRONIC CONDITION RESULTING IN FIBROSIS OF THE KIDNEY AND PERMANENT CHANGES IN THE ORGAN'S FUNCTION. TWO NEW STUDIES SUGGEST THAT CELL CYCLE ARREST OF EPITHELIAL CELLS AND EPIGENETIC MODIFICATIONS HAVE KEY ROLES IN THE SWITCH TO CHRONIC DISEASE (PAGES 535-543 AND 544-550). 2010