1 4432 96 MOLECULAR CHARACTERIZATION OF RICHTER SYNDROME IDENTIFIES DE NOVO DIFFUSE LARGE B-CELL LYMPHOMAS WITH POOR PROGNOSIS. RICHTER SYNDROME (RS) IS THE TRANSFORMATION OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) INTO AGGRESSIVE LYMPHOMA, MOST COMMONLY DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL). WE CHARACTERIZE 58 PRIMARY HUMAN RS SAMPLES BY GENOME-WIDE DNA METHYLATION AND WHOLE-TRANSCRIPTOME PROFILING. OUR COMPREHENSIVE APPROACH DETERMINES RS DNA METHYLATION PROFILE AND UNRAVELS A CLL EPIGENETIC IMPRINT, ALLOWING CLL-RS CLONAL RELATIONSHIP ASSESSMENT WITHOUT THE NEED OF THE INITIAL CLL TUMOR DNA. DNA METHYLATION- AND TRANSCRIPTOMIC-BASED CLASSIFIERS WERE DEVELOPED, AND TESTING ON LANDMARK DLBCL DATASETS IDENTIFIES A POOR-PROGNOSIS, ACTIVATED B-CELL-LIKE DLBCL SUBSET IN 111/1772 SAMPLES. THE CLASSIFICATION ROBUSTLY IDENTIFIES PHENOTYPES VERY SIMILAR TO RS WITH A SPECIFIC GENOMIC PROFILE, ACCOUNTING FOR 4.3-8.3% OF DE NOVO DLBCLS. IN THIS WORK, RS MULTI-OMICS CHARACTERIZATION DETERMINES ONCOGENIC MECHANISMS, ESTABLISHES A SURROGATE MARKER FOR CLL-RS CLONAL RELATIONSHIP, AND PROVIDES A CLINICALLY RELEVANT CLASSIFIER FOR A SUBSET OF PRIMARY "RS-TYPE DLBCL" WITH UNFAVORABLE PROGNOSIS. 2023 2 3024 34 GENETICS AND PATHOGENESIS OF DIFFUSE LARGE B-CELL LYMPHOMA. BACKGROUND: DIFFUSE LARGE B-CELL LYMPHOMAS (DLBCLS) ARE PHENOTYPICALLY AND GENETICALLY HETEROGENEOUS. GENE-EXPRESSION PROFILING HAS IDENTIFIED SUBGROUPS OF DLBCL (ACTIVATED B-CELL-LIKE [ABC], GERMINAL-CENTER B-CELL-LIKE [GCB], AND UNCLASSIFIED) ACCORDING TO CELL OF ORIGIN THAT ARE ASSOCIATED WITH A DIFFERENTIAL RESPONSE TO CHEMOTHERAPY AND TARGETED AGENTS. WE SOUGHT TO EXTEND THESE FINDINGS BY IDENTIFYING GENETIC SUBTYPES OF DLBCL BASED ON SHARED GENOMIC ABNORMALITIES AND TO UNCOVER THERAPEUTIC VULNERABILITIES BASED ON TUMOR GENETICS. METHODS: WE STUDIED 574 DLBCL BIOPSY SAMPLES USING EXOME AND TRANSCRIPTOME SEQUENCING, ARRAY-BASED DNA COPY-NUMBER ANALYSIS, AND TARGETED AMPLICON RESEQUENCING OF 372 GENES TO IDENTIFY GENES WITH RECURRENT ABERRATIONS. WE DEVELOPED AND IMPLEMENTED AN ALGORITHM TO DISCOVER GENETIC SUBTYPES BASED ON THE CO-OCCURRENCE OF GENETIC ALTERATIONS. RESULTS: WE IDENTIFIED FOUR PROMINENT GENETIC SUBTYPES IN DLBCL, TERMED MCD (BASED ON THE CO-OCCURRENCE OF MYD88(L265P) AND CD79B MUTATIONS), BN2 (BASED ON BCL6 FUSIONS AND NOTCH2 MUTATIONS), N1 (BASED ON NOTCH1 MUTATIONS), AND EZB (BASED ON EZH2 MUTATIONS AND BCL2 TRANSLOCATIONS). GENETIC ABERRATIONS IN MULTIPLE GENES DISTINGUISHED EACH GENETIC SUBTYPE FROM OTHER DLBCLS. THESE SUBTYPES DIFFERED PHENOTYPICALLY, AS JUDGED BY DIFFERENCES IN GENE-EXPRESSION SIGNATURES AND RESPONSES TO IMMUNOCHEMOTHERAPY, WITH FAVORABLE SURVIVAL IN THE BN2 AND EZB SUBTYPES AND INFERIOR OUTCOMES IN THE MCD AND N1 SUBTYPES. ANALYSIS OF GENETIC PATHWAYS SUGGESTED THAT MCD AND BN2 DLBCLS RELY ON "CHRONIC ACTIVE" B-CELL RECEPTOR SIGNALING THAT IS AMENABLE TO THERAPEUTIC INHIBITION. CONCLUSIONS: WE UNCOVERED GENETIC SUBTYPES OF DLBCL WITH DISTINCT GENOTYPIC, EPIGENETIC, AND CLINICAL CHARACTERISTICS, PROVIDING A POTENTIAL NOSOLOGY FOR PRECISION-MEDICINE STRATEGIES IN DLBCL. (FUNDED BY THE INTRAMURAL RESEARCH PROGRAM OF THE NATIONAL INSTITUTES OF HEALTH AND OTHERS.). 2018 3 5512 33 RICHTER SYNDROME IN CHRONIC LYMPHOCYTIC LEUKEMIA: UPDATES ON BIOLOGY, CLINICAL FEATURES AND THERAPY. RICHTER SYNDROME (RS) OR RICHTER TRANSFORMATION IS THE DEVELOPMENT OF SECONDARY AGGRESSIVE LYMPHOMA IN THE SETTING OF UNDERLYING CHRONIC LYMPHOCYTIC LEUKEMIA/SMALL LYMPHOCYTIC LYMPHOMA (CLL/SLL). MOST FREQUENTLY CLL TRANSFORMS INTO DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL) (90%) AND RARELY (10%) INTO HODGKIN LYMPHOMA, TERMED HODGKIN VARIANT OF RICHTER SYNDROME (HVRS). RS IS GENERALLY CHARACTERIZED BY AN AGGRESSIVE CLINICAL COURSE AND POOR PROGNOSIS. IN RECENT YEARS, MAJOR ADVANCES HAVE BEEN MADE IN UNDERSTANDING GENETIC EVENTS WHICH RELATE TO THE PROGRESSION OF CLL OR TRANSFORMATION INTO RS. BETTER UNDERSTANDING OF THE MOLECULAR PATHWAYS HAS REVEALED THAT RS IS NOT A SINGLE HOMOGENEOUS ENTITY. THE MAJORITY OF CASES ARE CLONALLY RELATED TO THE ORIGINAL CLL CLONE, WHILE A MINORITY DEVELOP FROM AN UNRELATED CLONE. THIS REVIEW SUMMARIZES NEW DATA RELATING TO THE MOLECULAR BIOLOGY AND THE GENETIC/EPIGENETIC CHANGES OCCURRING DURING RICHTER TRANSFORMATION, AND ALSO CONSIDERS THE CLINICAL FEATURES AND THERAPY FOR BOTH DLBCL-RS AND HODGKIN VARIANT-RS. 2015 4 1693 35 DUSP4 DEFICIENCY CAUSED BY PROMOTER HYPERMETHYLATION DRIVES JNK SIGNALING AND TUMOR CELL SURVIVAL IN DIFFUSE LARGE B CELL LYMPHOMA. THE EPIGENETIC DYSREGULATION OF TUMOR SUPPRESSOR GENES IS AN IMPORTANT DRIVER OF HUMAN CARCINOGENESIS. WE HAVE COMBINED GENOME-WIDE DNA METHYLATION ANALYSES AND GENE EXPRESSION PROFILING AFTER PHARMACOLOGICAL DNA DEMETHYLATION WITH FUNCTIONAL SCREENING TO IDENTIFY NOVEL TUMOR SUPPRESSORS IN DIFFUSE LARGE B CELL LYMPHOMA (DLBCL). WE FIND THAT A CPG ISLAND IN THE PROMOTER OF THE DUAL-SPECIFICITY PHOSPHATASE DUSP4 IS ABERRANTLY METHYLATED IN NODAL AND EXTRANODAL DLBCL, IRRESPECTIVE OF ABC OR GCB SUBTYPE, RESULTING IN LOSS OF DUSP4 EXPRESSION IN 75% OF >200 EXAMINED CASES. THE DUSP4 GENOMIC LOCUS IS FURTHER DELETED IN UP TO 13% OF AGGRESSIVE B CELL LYMPHOMAS, AND THE LACK OF DUSP4 IS A NEGATIVE PROGNOSTIC FACTOR IN THREE INDEPENDENT COHORTS OF DLBCL PATIENTS. ECTOPIC EXPRESSION OF WILD-TYPE DUSP4, BUT NOT OF A PHOSPHATASE-DEFICIENT MUTANT, DEPHOSPHORYLATES C-JUN N-TERMINAL KINASE (JNK) AND INDUCES APOPTOSIS IN DLBCL CELLS. PHARMACOLOGICAL OR DOMINANT-NEGATIVE JNK INHIBITION RESTRICTS DLBCL SURVIVAL IN VITRO AND IN VIVO AND SYNERGIZES STRONGLY WITH THE BRUTON'S TYROSINE KINASE INHIBITOR IBRUTINIB. OUR RESULTS INDICATE THAT DLBCL CELLS DEPEND ON JNK SIGNALING FOR SURVIVAL. THIS FINDING PROVIDES A MECHANISTIC BASIS FOR THE CLINICAL DEVELOPMENT OF JNK INHIBITORS IN DLBCL, IDEALLY IN SYNTHETIC LETHAL COMBINATIONS WITH INHIBITORS OF CHRONIC ACTIVE B CELL RECEPTOR SIGNALING. 2015 5 5462 25 RESEARCH PROGRESS ON EPIGENETICS OF SMALL B-CELL LYMPHOMA. SMALL B-CELL LYMPHOMA IS THE CLASSIFICATION OF B-CELL CHRONIC LYMPHOPROLIFERATIVE DISORDERS THAT INCLUDE CHRONIC LYMPHOCYTIC LEUKAEMIA/SMALL LYMPHOCYTIC LYMPHOMA, FOLLICULAR LYMPHOMA, MANTLE CELL LYMPHOMA, MARGINAL ZONE LYMPHOMA, LYMPHOPLASMACYTIC LYMPHOMA/WALDENSTROM MACROGLOBULINEMIA. THE CLINICAL PRESENTATION IS SOMEWHAT HETEROGENEOUS, AND ITS OCCURRENCE AND DEVELOPMENT MECHANISMS ARE NOT YET PRECISE AND MAY INVOLVE EPIGENETIC CHANGES. EPIGENETIC ALTERATIONS MAINLY INCLUDE DNA METHYLATION, HISTONE MODIFICATION, AND NON-CODING RNA, WHICH ARE ESSENTIAL FOR GENETIC DETECTION, EARLY DIAGNOSIS, AND ASSESSMENT OF TREATMENT RESISTANCE IN SMALL B-CELL LYMPHOMA. AS CHRONIC LYMPHOCYTIC LEUKEMIA/SMALL LYMPHOCYTIC LYMPHOMA HAS ALREADY BEEN REPORTED IN THE LITERATURE, THIS ARTICLE FOCUSES ON SMALL B-CELL LYMPHOMAS SUCH AS FOLLICULAR LYMPHOMA, MANTLE CELL LYMPHOMA, MARGINAL ZONE LYMPHOMA, AND WALDENSTROM MACROGLOBULINEMIA. IT DISCUSSES RECENT DEVELOPMENTS IN EPIGENETIC RESEARCH TO DIAGNOSE AND TREAT THIS GROUP OF LYMPHOMAS. THIS REVIEW PROVIDES NEW IDEAS FOR THE TREATMENT AND PROGNOSIS ASSESSMENT OF SMALL B-CELL LYMPHOMA BY EXPLORING THE CONNECTION BETWEEN SMALL B-CELL LYMPHOMA AND EPIGENETICS. 2022 6 1467 30 DISTINCT CLINICAL AND GENETIC FEATURES OF HEPATITIS B VIRUS-ASSOCIATED FOLLICULAR LYMPHOMA IN CHINESE PATIENTS. HEPATITIS B VIRUS (HBV) INFECTION HAS BEEN ASSOCIATED WITH AN INCREASED RISK FOR B-CELL LYMPHOMAS. WE PREVIOUSLY SHOWED THAT 20% OF DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL) PATIENTS FROM CHINA, AN ENDEMIC AREA OF HBV INFECTION, HAVE CHRONIC HBV INFECTION (SURFACE ANTIGEN-POSITIVE, HBSAG+) AND ARE CHARACTERIZED BY DISTINCT CLINICAL AND GENETIC FEATURES. HERE, WE SHOWED THAT 24% OF FOLLICULAR LYMPHOMA (FL) CHINESE PATIENTS ARE HBSAG+. COMPARED WITH THE HBSAG- FL PATIENTS, HBSAG+ PATIENTS ARE YOUNGER, HAVE A HIGHER HISTOLOGICAL GRADE AT DIAGNOSIS, AND HAVE A HIGHER INCIDENCE OF DISEASE PROGRESSION WITHIN 24 MONTHS. MOREOVER, BY SEQUENCING THE GENOMES OF 109 FL TUMORS, WE OBSERVED ENHANCED MUTAGENESIS AND DISTINCT GENETIC PROFILE IN HBSAG+ FLS, WITH A UNIQUE SET OF PREFERENTIALLY MUTATED GENES (TNFAIP3, FAS, HIST1H1C, KLF2, TP53, PIM1, TMSB4X, DUSP2, TAGAP, LYN, AND SETD2) BUT LACK OF THE HALLMARK OF HBSAG- FLS (IE, IGH/BCL2 TRANSLOCATIONS AND CREBBP MUTATIONS). TRANSCRIPTOMIC ANALYSES FURTHER SHOWED THAT HBSAG+ FLS DISPLAYED GENE-EXPRESSION SIGNATURES RESEMBLING THE ACTIVATED B-CELL-LIKE SUBTYPE OF DIFFUSE LARGE B-CELL LYMPHOMA, INVOLVING IRF4-TARGETED GENES AND NF-KAPPAB/MYD88 SIGNALING PATHWAYS. FINALLY, WE IDENTIFIED AN INCREASED INFILTRATION OF CD8+ MEMORY T CELLS, CD4+ TH1 CELLS, AND M1 MACROPHAGES AND HIGHER T-CELL EXHAUSTION GENE SIGNATURE IN HBSAG+ FL SAMPLES. TAKEN TOGETHER, WE PRESENT NEW GENETIC/EPIGENETIC EVIDENCE THAT LINKS CHRONIC HBV INFECTION TO B-CELL LYMPHOMAGENESIS, AND HBV-ASSOCIATED FL IS LIKELY TO HAVE A DISTINCT CELL-OF-ORIGIN AND REPRESENT AS A SEPARATE SUBTYPE OF FL. TARGETABLE GENETIC/EPIGENETIC ALTERATIONS IDENTIFIED IN TUMORS AND THEIR ASSOCIATED TUMOR MICROENVIRONMENT MAY PROVIDE POTENTIAL NOVEL THERAPEUTIC APPROACHES FOR THIS SUBGROUP OF PATIENTS. 2022 7 4874 28 OVERCOMING ACQUIRED EPIGENETIC RESISTANCE TO BTK INHIBITORS. THE USE OF BRUTON TYROSINE KINASE (BTK) INHIBITORS TO BLOCK B-CELL RECEPTOR (BCR)-DEPENDENT NF-KAPPAB ACTIVATION IN LYMPHOID MALIGNANCIES HAS BEEN A MAJOR CLINICAL ADVANCE, YET ACQUIRED THERAPEUTIC RESISTANCE IS A RECURRING PROBLEM. WE MODELED THE DEVELOPMENT OF RESISTANCE TO THE BTK INHIBITOR IBRUTINIB IN THE ACTIVATED B-CELL (ABC) SUBTYPE OF DIFFUSE LARGE B-CELL LYMPHOMA, WHICH RELIES ON CHRONIC ACTIVE BCR SIGNALING FOR SURVIVAL. THE PRIMARY MODE OF RESISTANCE WAS EPIGENETIC, DRIVEN IN PART BY THE TRANSCRIPTION FACTOR TCF4. THE RESULTANT PHENOTYPIC SHIFT ALTERED BCR SIGNALING SUCH THAT THE GTPASE RAC2 SUBSTITUTED FOR BTK IN THE ACTIVATION OF PHOSPHOLIPASE CGAMMA2, THEREBY SUSTAINING NF-KAPPAB ACTIVITY. THE INTERACTION OF RAC2 WITH PHOSPHOLIPASE CGAMMA2 WAS ALSO INCREASED IN CHRONIC LYMPHOCYTIC LEUKEMIA CELLS FROM PATIENTS WITH PERSISTENT OR PROGRESSIVE DISEASE ON BTK INHIBITOR TREATMENT. WE IDENTIFIED CLINICALLY AVAILABLE DRUGS THAT CAN TREAT EPIGENETIC IBRUTINIB RESISTANCE, SUGGESTING COMBINATION THERAPEUTIC STRATEGIES. SIGNIFICANCE: IN DIFFUSE LARGE B-CELL LYMPHOMA, WE SHOW THAT PRIMARY RESISTANCE TO BTK INHIBITORS IS DUE TO EPIGENETIC RATHER THAN GENETIC CHANGES THAT CIRCUMVENT THE BTK BLOCKADE. WE ALSO OBSERVED THIS RESISTANCE MECHANISM IN CHRONIC LYMPHOCYTIC LEUKEMIA, SUGGESTING THAT EPIGENETIC ALTERATIONS MAY CONTRIBUTE MORE TO BTK INHIBITOR RESISTANCE THAN CURRENTLY THOUGHT.SEE RELATED COMMENTARY BY PASQUALUCCI, P. 555. THIS ARTICLE IS HIGHLIGHTED IN THE IN THIS ISSUE FEATURE, P. 549. 2021 8 185 28 ACCUMULATION OF ABERRANT CPG HYPERMETHYLATION BY HELICOBACTER PYLORI INFECTION PROMOTES DEVELOPMENT AND PROGRESSION OF GASTRIC MALT LYMPHOMA. ABERRANT DNA HYPERMETHYLATION IS AN IMPORTANT MECHANISM FOR THE INACTIVATION OF TUMOR-RELATED GENES IN HUMAN TUMORS. GASTRIC MUCOSA-ASSOCIATED LYMPHOID TISSUE (MALT) LYMPHOMAS ARISE FROM HELICOBACTER PYLORI-ASSOCIATED CHRONIC GASTRITIS; MOST PATIENTS ARE H. PYLORI-POSITIVE AND ERADICATION THERAPY IS HIGHLY EFFECTIVE. IN THE PRESENT STUDY, WE USED METHYLATION-SPECIFIC PCR TO ANALYZE THE DNA METHYLATION STATUS OF 11 TUMOR-RELATED GENES (KIP2, P16, HMLH-1, P15, P73, MGMT, DAPK, MINT1, MINT2, MINT31 AND HCAD) IN 21 SPECIMENS OF MALT LYMPHOMA, 5 SPECIMENS OF MALT LYMPHOMA WITH LARGE CELL COMPONENT (HIGH-GRADE MALT LYMPHOMA), 15 SPECIMENS OF DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL), 8 SPECIMENS OF COMPLETE REMISSION OF MALT LYMPHOMA AFTER ERADICATION THERAPY, 5 SPECIMENS WITH NO EVIDENCE OF MALIGNANCY AND PBMCS FROM 10 HEALTHY DONORS. THE AVERAGE NUMBER OF METHYLATED GENES WAS SIGNIFICANTLY GREATER IN GASTRIC LYMPHOMAS AS COMPARED TO NORMAL CONTROLS (P<0.001). THE CPG ISLAND METHYLATOR PHENOTYPE (CIMP) WAS OBSERVED IN 93.3% (14/15) OF DLBCLS, 100% (5/5) OF HIGH-GRADE MALT LYMPHOMAS AND 61.9% (13/21) OF MALT LYMPHOMAS; IN CONTRAST, CIMP WAS NOT FOUND IN THE CONTROL GROUP (0%). THE AVERAGE NUMBER OF METHYLATED GENES AND THE CIMP INCIDENCE SIGNIFICANTLY INCREASED WITH H. PYLORI INFECTION. FURTHERMORE, ABERRANT CPG METHYLATION OF SPECIFIC GENES, SUCH AS P16, MGMT AND MINT31, WAS CONSISTENTLY ASSOCIATED WITH H. PYLORI INFECTION. THESE FINDINGS STRONGLY SUGGEST THAT H. PYLORI INFECTION CAUSES THE ABERRANT DNA HYPERMETHYLATION OF SPECIFIC GENES AND INDUCES CIMP, WHICH IS AN IMPORTANT EPIGENETIC MECHANISM FOR THE DEVELOPMENT AND PROGRESSION OF GASTRIC MALT LYMPHOMA; ADDITIONALLY, OUR FINDINGS PROVIDE NEW EPIGENETIC MARKERS. 2009 9 3902 30 LEARNING FROM THE FAILURES OF DRUG DISCOVERY IN B-CELL NON-HODGKIN LYMPHOMAS AND PERSPECTIVES FOR THE FUTURE: CHRONIC LYMPHOCYTIC LEUKEMIA AND DIFFUSE LARGE B-CELL LYMPHOMA AS TWO ENDS OF A SPECTRUM IN DRUG DEVELOPMENT. DESPITE SUBSTANTIAL RECENT ADVANCES, THERE IS STILL AN UNMET NEED FOR BETTER THERAPIES IN B-CELL NON HODGKIN LYMPHOMAS (B-NHL), ESPECIALLY IN RELAPSED OR REFRACTORY DISEASE. MANY NOVEL TARGETED DRUGS HAVE BEEN DEVELOPED BASED ON A BETTER MOLECULAR UNDERSTANDING OF B-NHL. AREAS COVERED: THIS ARTICLE FOCUSES ON CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) AS A REPRESENTATIVE FOR INDOLENT LYMPHOMAS AND PARADIGMATIC FOR THE TREMENDOUS PROGRESS IN TREATING B-NHL ON THE ONE HAND AND DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL) AS A REPRESENTATIVE FOR AGGRESSIVE LYMPHOMAS AND PARADIGMATIC FOR MANY UNSOLVED PROBLEMS IN LYMPHOMA TREATMENT OR THE OTHER HAND. WE HIGHLIGHT SALIENT POINTS IN CURRENT THERAPIES TARGETING GENETIC, EPIGENETIC, IMMUNOLOGICAL AND MICROENVIRONMENTAL ALTERATIONS. POSSIBLE REASONS FOR DRUG FAILURE IN CLINICAL TRIALS LIKE TUMOR HETEROGENEITY, CLONAL EVOLUTION AND DRUG RESISTANCE MECHANISMS ARE DISCUSSED. BASED THEREON, SOME PERSPECTIVES FOR FURTHER DRUG DISCOVERY ARE GIVEN. EXPERT OPINION: IN VIEW OF THE PATHOGENETIC COMPLEXITY OF LYMPHOMAS, THERAPIES TARGETING EXCLUSIVELY A SINGLE ALTERATION MAY FAIL BECAUSE RESISTANCE MECHANISMS ARE PRESENT EITHER INITIALLY OR EVOLVE DURING TREATMENT. THEREFORE, FUTURE THERAPIES IN B-NHL MAY HAVE TO TARGET THE GREATEST POSSIBLE NUMBER OF GENETIC, IMMUNOLOGICAL OR EPIGENETIC ALTERATIONS STILL ALLOWING TOLERABILITY AND TO MONITOR THESE ALTERATIONS DURING THERAPY. 2017 10 6373 19 THE ROLE OF MIRNAS AND EPIGENETIC MECHANISMS IN PRIMARY GASTRIC MUCOSA-ASSOCIATED LYMPHOID TISSUE LYMPHOMA. GASTRIC MUCOSA-ASSOCIATED LYMPHOID TISSUE (MALT) LYMPHOMA IS A RARE LOW-GRADE B-CELL NON-HODGKIN LYMPHOMA ASSOCIATED WITH HELICOBACTER PYLORI INFECTION AND THE SUBSEQUENT CHRONIC INFLAMMATION. SIGNIFICANT PROGRESS IN UNDERSTANDING THE PATHOGENESIS OF THE DISEASE HAS ALREADY BEEN MADE. HOWEVER, THE EXACT MOLECULAR PATHWAYS OF LYMPHOMAGENESIS REMAIN UNCLEAR. FURTHERMORE, DIFFICULTIES REGARDING ACCURATE DIAGNOSIS OF GASTRIC MALT LYMPHOMA AND ITS DISCRIMINATION FROM GASTRITIS OR OTHER LYMPHOMA SUBTYPES ARISE. RECENT STUDIES EVALUATE THE ROLE OF MIRNAS AND EPIGENETIC ALTERATIONS ON MALT LYMPHOMA PATHOGENESIS AND PROGNOSIS. THIS REVIEW CRITICALLY SUMMARIZES THE MOST IMPORTANT DATA ON THE ROLE OF MIRNAS AND EPIGENETICS IN MALT LYMPHOMAS PATHOGENESIS, PROGNOSIS AND TREATMENT. 2016 11 1333 33 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 12 1445 23 DIFFUSE PEDIATRIC-TYPE HIGH-GRADE GLIOMA ARISING IN AN OVARIAN MATURE CYSTIC TERATOMA. IMMATURE NEUROECTODERMAL TISSUE CAN BE FOUND IN THE OVARY AS PART OF AN IMMATURE TERATOMA OR AS PART OF A TERATOMA WITH MALIGNANT NEUROECTODERMAL TRANSFORMATION. SUCH LESIONS MAY CLOSELY RESEMBLE CENTRAL NERVOUS SYSTEM TUMORS, BUT THEIR BIOLOGIC SIMILARITY IS UNCLEAR. WE DESCRIBE AN 18-YR-OLD FEMALE WHO PRESENTED WITH ABDOMINAL PAIN CAUSED BY AN OVARIAN MASS WITH WIDESPREAD METASTASES. HISTOLOGY SHOWED A PRIMITIVE, HIGH-GRADE TUMOR ARISING IN THE BACKGROUND OF A MATURE TERATOMA. THE TUMOR WAS SOX10 POSITIVE, WITH FOCAL EXPRESSION OF GFAP, S100, NSE, AND SYNAPTOPHYSIN. MOLECULAR ANALYSIS DEMONSTRATED CO-AMPLIFICATION OF PDGFRA AND KIT, ALTERATIONS COMMON IN HIGH-GRADE GLIOMAS. BY WHOLE-GENOME METHYLATION PROFILING, IT CLUSTERED INTO THE "DIFFUSE PEDIATRIC-TYPE HIGH-GRADE GLIOMA, RTK1 SUBTYPE, SUBCLASS C" GROUP. DESPITE PROGRESSING THROUGH 2 LINES OF CHEMOTHERAPY WITH WIDESPREAD METASTATIC DISEASE, SHE ACHIEVED AN EXCELLENT RESPONSE TO CHEMOTHERAPY DIRECTED TOWARD AGGRESSIVE GERM CELL TUMORS. THIS CASE EMPHASIZES THE IMPORTANCE OF IMMUNOHISTOCHEMICAL, GENOMIC, AND EPIGENETIC ANALYSES TO ACCURATELY CLASSIFY THESE EXCEEDINGLY RARE TUMORS AND DETERMINE THE OPTIMAL THERAPY. 2023 13 2992 26 GENETIC LANDSCAPE AND DEREGULATED PATHWAYS IN B-CELL LYMPHOID MALIGNANCIES. WITH THE INTRODUCTION OF NEXT-GENERATION SEQUENCING, THE GENETIC LANDSCAPE OF THE COMPLEX GROUP OF B-CELL LYMPHOID MALIGNANCIES HAS RAPIDLY BEEN UNRAVELLED IN RECENT YEARS. THIS HAS PROVIDED IMPORTANT INFORMATION ABOUT RECURRENT GENETIC EVENTS AND IDENTIFIED KEY PATHWAYS DEREGULATED IN EACH LYMPHOMA SUBTYPE. IN PARALLEL, THERE HAS BEEN INTENSE SEARCH AND DEVELOPMENT OF NOVEL TYPES OF TARGETED THERAPY THAT 'HIT' CENTRAL MECHANISMS IN LYMPHOMA PATHOBIOLOGY, SUCH AS BTK, PI3K OR BCL2 INHIBITORS. IN THIS REVIEW, WE WILL OUTLINE THE CURRENT VIEW OF THE GENETIC LANDSCAPE OF SELECTED ENTITIES: FOLLICULAR LYMPHOMA, DIFFUSE LARGE B-CELL LYMPHOMA, MANTLE CELL LYMPHOMA, CHRONIC LYMPHOCYTIC LEUKAEMIA AND MARGINAL ZONE LYMPHOMA. WE WILL DETAIL RECURRENT ALTERATIONS AFFECTING IMPORTANT SIGNALLING PATHWAYS, THAT IS THE B-CELL RECEPTOR/NF-KAPPAB PATHWAY, NOTCH SIGNALLING, JAK-STAT SIGNALLING, P53/DNA DAMAGE RESPONSE, APOPTOSIS AND CELL CYCLE REGULATION, AS WELL AS OTHER PERHAPS UNEXPECTED CELLULAR PROCESSES, SUCH AS IMMUNE REGULATION, CELL MIGRATION, EPIGENETIC REGULATION AND RNA PROCESSING. WHILST MANY OF THESE PATHWAYS/PROCESSES ARE COMMONLY ALTERED IN DIFFERENT LYMPHOID TUMORS, ALBEIT AT VARYING FREQUENCIES, OTHERS ARE PREFERENTIALLY TARGETED IN SELECTED B-CELL MALIGNANCIES. SOME OF THESE GENETIC LESIONS ARE EITHER INVOLVED IN DISEASE ONTOGENY OR LINKED TO THE EVOLUTION OF EACH DISEASE AND/OR SPECIFIC CLINICOBIOLOGICAL FEATURES, AND SOME OF THEM HAVE BEEN DEMONSTRATED TO HAVE PROGNOSTIC AND EVEN PREDICTIVE IMPACT. FUTURE WORK IS ESPECIALLY NEEDED TO UNDERSTAND THE THERAPY-RESISTANT DISEASE, PARTICULARLY IN PATIENTS TREATED WITH TARGETED THERAPY, AND TO IDENTIFY NOVEL TARGETS AND THERAPEUTIC STRATEGIES IN ORDER TO REALIZE TRUE PRECISION MEDICINE IN THIS CLINICALLY HETEROGENEOUS PATIENT GROUP. 2017 14 940 28 CHRONIC LYMPHOCYTIC LEUKEMIA AND MANTLE CELL LYMPHOMA: CROSSROADS OF GENETIC AND MICROENVIRONMENT INTERACTIONS. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) AND MANTLE CELL LYMPHOMA (MCL) ARE 2 WELL-DEFINED ENTITIES THAT DIVERGE IN THEIR BASIC PATHOGENIC MECHANISMS AND CLINICAL EVOLUTION BUT THEY SHARE EPIDEMIOLOGICAL CHARACTERISTICS, CELLS OF ORIGIN, MOLECULAR ALTERATIONS, AND CLINICAL FEATURES THAT DIFFER FROM OTHER LYMPHOID NEOPLASMS. CLL AND MCL ARE CLASSICALLY CONSIDERED INDOLENT AND AGGRESSIVE NEOPLASMS, RESPECTIVELY. HOWEVER, THE CLINICAL EVOLUTION OF BOTH TUMORS IS VERY HETEROGENEOUS, WITH SUBSETS OF PATIENTS HAVING STABLE DISEASE FOR A LONG TIME WHEREAS OTHERS REQUIRE IMMEDIATE INTERVENTION. BOTH CLL AND MCL INCLUDE 2 MAJOR MOLECULAR SUBTYPES THAT SEEM TO DERIVE FROM ANTIGEN-EXPERIENCED CD5(+) B CELLS THAT RETAIN A NAIVE OR MEMORY-LIKE EPIGENETIC SIGNATURE AND CARRY A VARIABLE LOAD OF IMMUNOGLOBULIN HEAVY-CHAIN VARIABLE REGION SOMATIC MUTATIONS FROM TRULY UNMUTATED TO HIGHLY MUTATED, RESPECTIVELY. THESE 2 SUBTYPES OF TUMORS DIFFER IN THEIR MOLECULAR PATHWAYS, GENOMIC ALTERATIONS, AND CLINICAL BEHAVIOR, BEING MORE AGGRESSIVE IN NAIVE-LIKE THAN MEMORY-LIKE-DERIVED TUMORS IN BOTH CLL AND MCL. THE PATHOGENESIS OF THE 2 ENTITIES INTEGRATES THE RELEVANT INFLUENCE OF B-CELL RECEPTOR SIGNALING, TUMOR CELL MICROENVIRONMENT INTERACTIONS, GENOMIC ALTERATIONS, AND EPIGENOME MODIFICATIONS THAT CONFIGURE THE EVOLUTION OF THE TUMORS AND OFFER NEW POSSIBILITIES FOR THERAPEUTIC INTERVENTION. THIS REVIEW WILL FOCUS ON THE SIMILARITIES AND DIFFERENCES OF THESE 2 TUMORS BASED ON RECENT STUDIES THAT ARE ENHANCING THE UNDERSTANDING OF THEIR PATHOGENESIS AND CREATING SOLID BASES FOR NEW MANAGEMENT STRATEGIES. 2018 15 557 27 B-CELL ANTIGEN RECEPTOR SIGNALING IN CHRONIC LYMPHOCYTIC LEUKEMIA: THERAPEUTIC TARGETS AND TRANSLATIONAL OPPORTUNITIES. B-CELL CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY CLONALLY EXPANDED AND MOLECULARLY HETEROGENEOUS POPULATIONS OF B LYMPHOCYTES WITH IMPAIRED APOPTOTIC MECHANISMS. THIS OCCURS AS A RESULT OF MULTIPLE GENETIC AND EPIGENETIC ABNORMALITIES, INCLUDING CHROMOSOMAL ABERRATIONS AND ENHANCER REGION HYPOMETHYLATION, OFTEN IMPINGING ON INTRACELLULAR SIGNALING PATHWAYS THAT ARE ESSENTIAL TO NORMAL B-CELL ACTIVATION, PROLIFERATION, AND SURVIVAL. THE B-CELL ANTIGEN RECEPTOR (BCR) SIGNALING IS ONE SUCH PATHWAY USURPED BY MALIGNANT B CELLS, AS EXEMPLIFIED BY THE EARLY PHASE CLINICAL SUCCESS ACHIEVED BY SMALL-MOLECULE AGENTS TARGETING KEY PLAYERS INVOLVED IN THE PATHWAY. SUCH NEW TARGETED AGENTS, INCLUDING THOSE THAT INHIBIT THE FUNCTION OF SPLEEN TYROSINE KINASE (SYK), BRUTON'S TYROSINE KINASE (BTK), PHOSPHATIDYLINOSITOL 3-KINASES (PI3K), AND B-CELL LYMPHOMA 2 (BCL-2), ALONG WITH THE CURRENT STANDARD THERAPY COMPRISING CHEMO-IMMUNOTHERAPIES WITH OR WITHOUT B-CELL DEPLETING BIOLOGIC AGENT RITUXIMAB (ANTI-CD20 MONOCLONAL ANTIBODY), SHOULD EXPAND THE ARMAMENTARIUM FOR CLL THERAPY. WE REVIEW THE THERAPEUTIC AGENTS CURRENTLY IN CLINICAL DEVELOPMENT WHICH TARGET DIFFERENT EFFECTORS OF THE MALIGNANT BCR SIGNALING, AND DISCUSS THEIR OVERLAPPING AND DISCRIMINATING TRANSLATIONAL OPPORTUNITIES IN THE CONTEXT OF CLL TREATMENT. 2013 16 941 33 CHRONIC LYMPHOCYTIC LEUKEMIA B-CELL NORMAL CELLULAR COUNTERPART: CLUES FROM A FUNCTIONAL PERSPECTIVE. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY THE CLONAL EXPANSION OF SMALL MATURE-LOOKING CD19+ CD23+ CD5+ B-CELLS THAT ACCUMULATE IN THE BLOOD, BONE MARROW, AND LYMPHOID ORGANS. TO DATE, NO CONSENSUS HAS BEEN REACHED CONCERNING THE NORMAL CELLULAR COUNTERPART OF CLL B-CELLS AND SEVERAL B-CELL TYPES HAVE BEEN PROPOSED. CLL B-CELLS HAVE REMARKABLE PHENOTYPIC AND GENE EXPRESSION PROFILE HOMOGENEITY. IN RECENT YEARS, THE MOLECULAR AND CELLULAR BIOLOGY OF CLL HAS BEEN ENRICHED BY SEMINAL INSIGHTS THAT ARE LEADING TO A BETTER UNDERSTANDING OF THE NATURAL HISTORY OF THE DISEASE. IMMUNOPHENOTYPIC AND MOLECULAR APPROACHES (INCLUDING IMMUNOGLOBULIN HEAVY-CHAIN VARIABLE GENE MUTATIONAL STATUS, TRANSCRIPTIONAL AND EPIGENETIC PROFILING) COMPARING THE NORMAL B-CELL SUBSET AND CLL B-CELLS PROVIDE SOME NEW INSIGHTS INTO THE NORMAL CELLULAR COUNTERPART. FUNCTIONAL CHARACTERISTICS (INCLUDING ACTIVATION REQUIREMENTS AND PROPENSITY FOR PLASMA CELL DIFFERENTIATION) OF CLL B-CELLS HAVE NOW BEEN INVESTIGATED FOR 50 YEARS. B-CELL SUBSETS DIFFER SUBSTANTIALLY IN TERMS OF THEIR FUNCTIONAL FEATURES. ANALYSIS OF SHARED FUNCTIONAL CHARACTERISTICS MAY REVEAL SIMILARITIES BETWEEN NORMAL B-CELL SUBSETS AND CLL B-CELLS, ALLOWING SPECULATIVE ASSIGNMENT OF A NORMAL CELLULAR COUNTERPART FOR CLL B-CELLS. IN THIS REVIEW, WE SUMMARIZE CURRENT DATA REGARDING PERIPHERAL B-CELL DIFFERENTIATION AND HUMAN B-CELL SUBSETS AND SUGGEST POSSIBILITIES FOR A NORMAL CELLULAR COUNTERPART BASED ON THE FUNCTIONAL CHARACTERISTICS OF CLL B-CELLS. HOWEVER, A DEFINITIVE NORMAL CELLULAR COUNTERPART CANNOT BE ATTRIBUTED ON THE BASIS OF THE AVAILABLE DATA. WE DISCUSS THE FUNCTIONAL CHARACTERISTICS REQUIRED FOR A CELL TO BE LOGICALLY CONSIDERED TO BE THE NORMAL COUNTERPART OF CLL B-CELLS. 2018 17 4922 24 PARENTAL AGE AND RISK OF LYMPHOID NEOPLASMS. HIGH PARENTAL AGE AT CHILDBIRTH HAS REPEATEDLY BEEN LINKED TO CHILDHOOD MALIGNANCIES, WHILE FEW STUDIES HAVE FOCUSED ON THE OFFSPRING'S RISK OF ADULT CANCER. IN THIS POPULATION-BASED CASE-CONTROL STUDY, WE IDENTIFIED 32,000 PATIENTS WITH LYMPHOID NEOPLASMS, DIAGNOSED AT AGES 0-79 YEARS DURING THE PERIOD 1987-2011, AND 160,000 MATCHED CONTROLS IN SWEDEN. USING PROSPECTIVELY REGISTERED DATA ON THEIR FIRST-DEGREE RELATIVES, WE EVALUATED THE IMPACT OF PARENTAL AGE ON THE RISK OF LYMPHOID NEOPLASMS BY SUBTYPE. OVERALL, EACH 5-YEAR INCREMENT IN MATERNAL AGE WAS ASSOCIATED WITH A 3% INCREASE IN INCIDENCE OF OFFSPRING LYMPHOID NEOPLASMS (HAZARD RATIO = 1.03, 95% CONFIDENCE INTERVAL: 1.02, 1.04). THE ASSOCIATION WAS SIMILAR FOR PATERNAL AGE AND PRESENT EVEN AMONG INDIVIDUALS OLDER THAN 70 YEARS OF AGE AT DIAGNOSIS. STRATIFIED ANALYSES FURTHER REVEALED THAT THE ASSOCIATION WAS LIMITED TO CERTAIN SUBTYPES, MOSTLY OF INDOLENT NATURE. RISKS OF CHRONIC LYMPHOCYTIC LEUKEMIA, FOLLICULAR LYMPHOMA, AND MANTLE CELL LYMPHOMA WERE 5%-10% HIGHER PER 5-YEAR INCREMENT IN MATERNAL AGE, BUT NO ASSOCIATIONS WERE OBSERVED FOR ACUTE LYMPHOBLASTIC LEUKEMIA, PLASMA CELL NEOPLASMS, OR DIFFUSE LARGE B-CELL LYMPHOMA. THESE FINDINGS INDICATED THAT PRENATAL GENETIC OR EPIGENETIC CHANGES INFLUENCE RISK OF ADULT LYMPHOID NEOPLASMS AND SUGGEST A DIFFERENCE IN THIS ASSOCIATION BETWEEN AGGRESSIVE AND INDOLENT LYMPHOMA SUBTYPES. 2017 18 741 24 CANDIDATE GENES OF WALDENSTROM'S MACROGLOBULINEMIA: CURRENT EVIDENCE AND RESEARCH. WALDENSTROM'S MACROGLOBULINEMIA (WM) IS A RELATIVELY UNCOMMON, INDOLENT MALIGNANCY OF IMMUNOGLOBULIN M-PRODUCING B CELLS. THE WORLD HEALTH ORGANIZATION CLASSIFIES IT AS A LYMPHOPLASMACYTIC LYMPHOMA AND PATIENTS TYPICALLY PRESENT WITH ANEMIA, HEPATOSPLENOMEGALY AND DIFFUSE LYMPHADENOPATHIES. HISTORICALLY, THE GENETIC CHARACTERIZATION OF THE DISEASE HAS BEEN HAMPERED BY THE RELATIVELY LOW PROLIFERATIVE RATE OF WM CELLS, THUS MAKING KARYOTYPING CHALLENGING. THE USE OF NOVEL TECHNOLOGIES SUCH AS FLUORESCENCE IN SITU HYBRIDIZATION, GENE ARRAY, AND WHOLE GENOME SEQUENCING HAS CONTRIBUTED GREATLY TO ESTABLISHING CANDIDATE GENES IN THE PATHOPHYSIOLOGY OF WM AND TO IDENTIFYING POTENTIAL TREATMENT TARGETS, SUCH AS L265P MYD88. THE DISCOVERY OF MICRORNAS AND THE RECOGNITION OF EPIGENETICS AS A MAJOR MODULATORY MECHANISM OF ONCOGENE EXPRESSION AND/OR ONCOSUPPRESSOR SILENCING HAVE AIDED IN FURTHER UNDERSTANDING THE PATHOGENESIS OF WM. ONCE THOUGHT TO CLOSELY RESEMBLE MULTIPLE MYELOMA, A CANCER OF TERMINALLY DIFFERENTIATED, IMMUNOGLOBULIN-SECRETING PLASMA CELLS, WM APPEARS TO GENETICALLY CLUSTER WITH OTHER INDOLENT B-CELL LYMPHOMAS SUCH AS CHRONIC LYMPHOCYTIC LEUKEMIA/SMALL CELL LYMPHOMA. THE RELATIVE HIGH INCIDENCE OF FAMILIAL CASES OF WM AND OTHER B-CELL MALIGNANCIES HAS BEEN HELPFUL IN IDENTIFYING HIGH-RISK GENE CANDIDATES. IN THIS REVIEW, WE FOCUS ON THE ESTABLISHED GENES INVOLVED IN THE PATHOGENESIS OF WM, WITH SPECIAL EMPHASIS ON THE KEY ROLE OF DERANGEMENT OF THE NUCLEAR FACTOR KAPPA B SIGNALING PATHWAY AND EPIGENETIC MECHANISMS. 2013 19 147 31 ABERRANT EPIGENETIC GENE REGULATION IN LYMPHOID MALIGNANCIES. IN LYMPHOID MALIGNANCIES, ABERRANT EPIGENETIC MECHANISMS SUCH AS DNA METHYLATION AND HISTONE MODIFICATIONS INFLUENCE CHROMATIN ARCHITECTURE AND CAN RESULT IN ALTERED GENE EXPRESSION. THESE ALTERATIONS COMMONLY AFFECT GENES THAT PLAY IMPORTANT ROLES IN THE CELL CYCLE, APOPTOSIS, AND DNA REPAIR IN NON-HODGKIN LYMPHOMA (NHL). THE ABILITY TO IDENTIFY EPIGENETIC MODIFICATIONS TO THESE IMPORTANT GENES HAS INCREASED EXPONENTIALLY DUE TO ADVANCES IN TECHNOLOGY. AS A RESULT, THERE ARE WELL-DEFINED, GENE-SPECIFIC EPIGENETIC ABERRATIONS ASSOCIATED WITH NHL COMPRISING FOLLICULAR LYMPHOMA (FL), MANTLE CELL LYMPHOMA (MCL), CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), AND DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL). THE IDENTIFICATION OF THESE GENES IS IMPORTANT BECAUSE THEY MAY BE USED AS BIOMARKERS FOR PROGNOSIS, DIAGNOSIS AND IN DEVELOPING IMPROVED TREATMENT STRATEGIES. ALSO IMPORTANT, IN THE CONTROL OF GENE EXPRESSION, IS THE PACKAGING OF DNA WITHIN THE NUCLEUS OF A CELL. THIS PACKAGING CAN BE DISTORTED BY EPIGENETIC ALTERATIONS AND MAY ALTER THE ACCESSIBILITY OF CERTAIN REGIONS OF THE GENOME IN CANCER CELLS. THIS REVIEW DISCUSSES THE IMPACT OF KNOWN EPIGENETIC ABERRATION ON THE REGULATION OF GENE EXPRESSION IN NHL AND PROVIDES INSIGHT INTO THE SPATIAL CONFORMATION OF THE GENOME (DNA PACKAGING) IN ACUTE LYMPHOBLASTIC LEUKEMIA. 2013 20 5245 30 PROGNOSTIC RELEVANCE OF INTEGRATED GENETIC PROFILING IN ADULT T-CELL LEUKEMIA/LYMPHOMA. ADULT T-CELL LEUKEMIA/LYMPHOMA (ATL) IS A HETEROGENEOUS GROUP OF PERIPHERAL T-CELL MALIGNANCIES CHARACTERIZED BY HUMAN T-CELL LEUKEMIA VIRUS TYPE-1 INFECTION, WHOSE GENETIC PROFILE HAS RECENTLY BEEN FULLY INVESTIGATED. HOWEVER, IT IS STILL POORLY UNDERSTOOD HOW THESE ALTERATIONS AFFECT CLINICAL FEATURES AND PROGNOSIS. WE INVESTIGATED THE EFFECTS OF GENETIC ALTERATIONS COMMONLY FOUND IN ATL ON DISEASE PHENOTYPES AND CLINICAL OUTCOMES, BASED ON GENOTYPING DATA OBTAINED FROM 414 AND 463 ATL PATIENTS USING TARGETED-CAPTURE SEQUENCING AND SINGLE NUCLEOTIDE POLYMORPHISM ARRAY KARYOTYPING, RESPECTIVELY. AGGRESSIVE (ACUTE/LYMPHOMA) SUBTYPES WERE ASSOCIATED WITH AN INCREASED BURDEN OF GENETIC AND EPIGENETIC ALTERATIONS, HIGHER FREQUENCIES OF TP53 AND IRF4 MUTATIONS, AND MANY COPY NUMBER ALTERATIONS (CNAS), INCLUDING PD-L1 AMPLIFICATIONS AND CDKN2A DELETIONS, COMPARED WITH INDOLENT (CHRONIC/SMOLDERING) SUBTYPES. BY CONTRAST, STAT3 MUTATIONS WERE MORE CHARACTERISTIC OF INDOLENT ATL. HIGHER NUMBERS OF SOMATIC MUTATIONS AND CNAS SIGNIFICANTLY CORRELATED WITH WORSE SURVIVAL. IN A MULTIVARIATE ANALYSIS INCORPORATING BOTH CLINICAL FACTORS AND GENETIC ALTERATIONS, THE JAPAN CLINICAL ONCOLOGY GROUP PROGNOSTIC INDEX HIGH-RISK, OLDER AGE, PRKCB MUTATIONS, AND PD-L1 AMPLIFICATIONS WERE INDEPENDENT POOR PROGNOSTIC FACTORS IN AGGRESSIVE ATL. IN INDOLENT ATL, IRF4 MUTATIONS, PD-L1 AMPLIFICATIONS, AND CDKN2A DELETIONS WERE SIGNIFICANTLY ASSOCIATED WITH SHORTER SURVIVAL, ALTHOUGH THE CHRONIC SUBTYPE WITH UNFAVORABLE CLINICAL FACTORS WAS ONLY MARGINALLY SIGNIFICANT. THUS, SOMATIC ALTERATIONS CHARACTERIZING AGGRESSIVE DISEASES PREDICT WORSE PROGNOSIS IN INDOLENT ATL, AMONG WHICH PD-L1 AMPLIFICATIONS ARE A STRONG GENETIC PREDICTOR IN BOTH AGGRESSIVE AND INDOLENT ATL. ATL SUBTYPES ARE FURTHER CLASSIFIED INTO MOLECULARLY DISTINCT SUBSETS WITH DIFFERENT PROGNOSIS. GENETIC PROFILING MIGHT CONTRIBUTE TO IMPROVED PROGNOSTICATION AND MANAGEMENT OF ATL PATIENTS. 2018