ABSTRACT
Diffuse large B cell lymphoma (DLBCL) is the most common form of blood cancer and is characterized by a striking degree of genetic and clinical heterogeneity. This heterogeneity poses a major barrier to understanding the genetic basis of the disease and its response to therapy. Here, we performed an integrative analysis of whole-exome sequencing and transcriptome sequencing in a cohort of 1,001 DLBCL patients to comprehensively define the landscape of 150 genetic drivers of the disease. We characterized the functional impact of these genes using an unbiased CRISPR screen of DLBCL cell lines to define oncogenes that promote cell growth. A prognostic model comprising these genetic alterations outperformed current established methods: cell of origin, the International Prognostic Index comprising clinical variables, and dual MYC and BCL2 expression. These results comprehensively define the genetic drivers and their functional roles in DLBCL to identify new therapeutic opportunities in the disease.
Subject(s)
CRISPR-Cas Systems , Gene Expression Profiling , Lymphoma, Large B-Cell, Diffuse/genetics , Antineoplastic Agents/administration & dosage , Cell Line, Tumor , Cells, Cultured , Exome , Female , Humans , Lymphoma, Large B-Cell, Diffuse/drug therapy , Male , Rituximab/administration & dosageABSTRACT
Neural stem cells, the source of newborn neurons in the adult hippocampus, are intimately involved in learning and memory, mood, and stress response. Despite considerable progress in understanding the biology of neural stem cells and neurogenesis, regulating the neural stem cell population precisely has remained elusive because we have lacked the specific targets to stimulate their proliferation and neurogenesis. The orphan nuclear receptor TLX/NR2E1 governs neural stem and progenitor cell self-renewal and proliferation, but the precise mechanism by which it accomplishes this is not well understood because its endogenous ligand is not known. Here, we identify oleic acid (18:1ω9 monounsaturated fatty acid) as such a ligand. We first show that oleic acid is critical for neural stem cell survival. Next, we demonstrate that it binds to TLX to convert it from a transcriptional repressor to a transcriptional activator of cell-cycle and neurogenesis genes, which in turn increases neural stem cell mitotic activity and drives hippocampal neurogenesis in mice. Interestingly, oleic acid-activated TLX strongly up-regulates cell cycle genes while only modestly up-regulating neurogenic genes. We propose a model in which sufficient quantities of this endogenous ligand must bind to TLX to trigger the switch to proliferation and drive the progeny toward neuronal lineage. Oleic acid thus serves as a metabolic regulator of TLX activity that can be used to selectively target neural stem cells, paving the way for future therapeutic manipulations to counteract pathogenic impairments of neurogenesis.
Subject(s)
Hippocampus , Neurogenesis , Oleic Acid , Receptors, Cytoplasmic and Nuclear , Animals , Cell Proliferation , Hippocampus/growth & development , Hippocampus/metabolism , Ligands , Mice , Neurogenesis/physiology , Oleic Acid/metabolism , Orphan Nuclear Receptors , Receptors, Cytoplasmic and Nuclear/metabolismABSTRACT
This study investigated the effect of musicianship on the perceptual integrality of tones and segmental information in non-native speech perception. We tested 112 Cantonese musicians, Cantonese non-musicians, English musicians, and English non-musicians with a modified Thai tone AX discrimination task. In the tone discrimination task, the control block only contained tonal variations, whereas the orthogonal block contained both tonal and task-irrelevant segmental variations. Relative to their own performance in the control block, the Cantonese listeners showed decreased sensitivity index (d') and increased response time in the orthogonal block, reflecting integral perception of tones and segmental information. By contrast, the English listeners performed similarly across the two blocks, indicating independent perception. Bayesian analysis revealed that the Cantonese musicians and the Cantonese non-musicians perceived Thai tones and segmental information equally integrally. Moreover, the English musicians and the English non-musicians showed similar degrees of independent perception. Based on the above results, musicianship does not seem to influence tone-segmental perceptual integrality. While musicianship apparently enhances tone sensitivity, not all musical advantages are transferrable to the language domain.
ABSTRACT
Advance directives for withholding life-saving treatment are controversial for dementia patients whose previously expressed wishes conflict with their currently expressed desires. To illustrate this ethical dilemma, McMahan conceives a hypothetical case in which an intellectually proud creative woman signs an advance directive stipulating her refusal to receive life-saving treatment if she contracts a fatal condition with dementia. However, when she develops dementia and forgets this advance directive, she contracts pneumonia and now expresses a desire to live. In response to such dilemmas, scholars like Norman Cantor have defended the moral authority of advance directives by giving credence to one's prior competent wishes over one's current incompetent preferences. I argue that their arguments, which are rooted in the principle of respect for autonomy, operate under ableist assumptions about incompetent persons and exclude other important features of respect. I propose an ethics of care model as an alternative moral approach that reconceptualises respect as a matter of caring about people's contemporaneous interests, even if they are not competently conceived. It fosters the virtues of care by encouraging healthcare providers to recognise dementia patients as legitimate narrative agents capable of authoring their own evolving life story. I argue that the ethics of care model not only provides an ethical defence of the creative woman's current incompetent desire to live despite her advance directive, but also vindicates our moral intuitions about what it means to demonstrate respect to dementia patients.
ABSTRACT
Burkitt lymphoma (BL) is an aggressive, MYC-driven lymphoma comprising 3 distinct clinical subtypes: sporadic BLs that occur worldwide, endemic BLs that occur predominantly in sub-Saharan Africa, and immunodeficiency-associated BLs that occur primarily in the setting of HIV. In this study, we comprehensively delineated the genomic basis of BL through whole-genome sequencing (WGS) of 101 tumors representing all 3 subtypes of BL to identify 72 driver genes. These data were additionally informed by CRISPR screens in BL cell lines to functionally annotate the role of oncogenic drivers. Nearly every driver gene was found to have both coding and non-coding mutations, highlighting the importance of WGS for identifying driver events. Our data implicate coding and non-coding mutations in IGLL5, BACH2, SIN3A, and DNMT1. Epstein-Barr virus (EBV) infection was associated with higher mutation load, with type 1 EBV showing a higher mutational burden than type 2 EBV. Although sporadic and immunodeficiency-associated BLs had similar genetic profiles, endemic BLs manifested more frequent mutations in BCL7A and BCL6 and fewer genetic alterations in DNMT1, SNTB2, and CTCF. Silencing mutations in ID3 were a common feature of all 3 subtypes of BL. In vitro, mass spectrometry-based proteomics demonstrated that the ID3 protein binds primarily to TCF3 and TCF4. In vivo knockout of ID3 potentiated the effects of MYC, leading to rapid tumorigenesis and tumor phenotypes consistent with those observed in the human disease.
Subject(s)
Burkitt Lymphoma/genetics , Whole Genome Sequencing/methods , Animals , Humans , MiceABSTRACT
PURPOSE OF REVIEW: Androgen deprivation therapy (ADT) is the standard of care for the treatment of advanced prostate cancer (PC). ADT, particularly with GnRH agonists, leads to increased risk of cardiovascular disease, including myocardial infarction, hypertension, and stroke. This review discusses the options of ADT, the mechanism of ADT-associated cardiovascular side effects, and potential benefit by using GnRH antagonists. RECENT FINDINGS: GnRH antagonists have relatively less cardiovascular adverse effects compared to GnRH agonists. We highlight on a recently published phase III clinical trial on the oral GnRH antagonist, relugolix, and its comparative benefit to traditional GnRH agonist regarding development of cardiovascular disease. Recent data reinforces that GnRH antagonists have a more favorable cardiovascular outcomes compared to GnRH agonists yet maintain a similar efficacy profile. From the data we reviewed, GnRH antagonists may be the preferred method of ADT for PC, but further data with primary cardiovascular outcomes are warranted.
Subject(s)
Cardiovascular Diseases , Myocardial Infarction , Prostatic Neoplasms , Androgen Antagonists/adverse effects , Androgens , Cardiovascular Diseases/chemically induced , Gonadotropin-Releasing Hormone , Humans , Male , Myocardial Infarction/chemically induced , Prostatic Neoplasms/drug therapyABSTRACT
BACKGROUND: Information technology and video gaming have potential advantages in the treatment of schizophrenia. However, information regarding the habits and attitudes related to internet use and video gaming in people with schizophrenia is limited. OBJECTIVE: The aim of this study was to explore the habits and attitudes regarding video gaming and information technology usage and their associated factors in people with schizophrenia in Hong Kong. METHODS: In this cross-sectional survey, service users with schizophrenia were recruited from 6 halfway hostels and 7 integrated centers for mental wellness in Hong Kong. A 79-item self-report questionnaire was utilized to explore the habits of internet use and video gaming in these people with schizophrenia. The attitude toward video gaming was assessed using the Gaming Attitudes, Motivations, and Experiences Scales. Of the 148 individuals in a convenience sample who were invited to participate in this study, 110 willingly participated (a response rate of 74.3%). The data were analyzed using descriptive statistics, a two-tailed independent t test, Pearson correlation, and principal analysis with 3 methods of rotation (varimax, equimax, and promax). RESULTS: Most participants (100/110, 90.9%) had access to the internet and half of them (54/110, 49.1%) used the internet daily mostly to watch videos (66/110, 60.0%) or read news or books, etc (42/110, 38.2%). One-third of the participants (36/110, 32.7%) used the internet to play web-based games, and most of them (88/110, 80.0%) had played a video game in the past year. The most favorable gaming platforms were cellular phones (43/88, 49%) followed by computers (19/88, 22%) and arcade cabinets (6/88, 7%). The most favorable game genre was action games (34/145, 23.4%). Those who had a bachelor's degree or higher scored lower in social interaction than those with a lower education level (P=.03). Those who played video games daily scored higher in the category of story than those who did not play daily (t86=2.03, P=.05). The most popular gaming category was autonomy and the least popular categories were violent catharsis and violent reward. Two motives, "social playing" and "evasive playing," were formed to describe the characteristics of playing video games. CONCLUSIONS: Our data showed a high internet utilization rate among people with schizophrenia in Hong Kong. Only a few of them used the internet to search for health-related information. Our study also exemplified the unique habits of gaming among the participants. Health care professionals could utilize video games to engage people with schizophrenia and promote coping with stress and provide social skills training to such people with schizophrenia. Identification of the gaming attitudes can contribute to the development of serious games for the schizophrenic population. Further investigation is vital for the promotion of mental health through web-based platforms.
Subject(s)
Information Technology/statistics & numerical data , Schizophrenic Psychology , Video Games/psychology , Adult , Attitude , Cross-Sectional Studies , Female , Habits , Humans , Internet , Male , Surveys and QuestionnairesABSTRACT
CD37 (tetraspanin TSPAN26) is a B-cell surface antigen widely expressed on mature B cells. CD37 is involved in immune regulation and tumor suppression but its function has not been fully elucidated. We assessed CD37 expression in de novo diffuse large B-cell lymphoma (DLBCL), and investigated its clinical and biologic significance in 773 patients treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) and 231 patients treated with CHOP. We found that CD37 loss (CD37-) in â¼60% of DLBCL patients showed significantly decreased survival after R-CHOP treatment, independent of the International Prognostic Index (IPI), germinal center B-cell-like (GCB)/activated B-cell-like (ABC) cell of origin, nodal/extranodal primary origin, and the prognostic factors associated with CD37-, including TP53 mutation, NF-κBhigh, Mychigh, phosphorylated STAT3high, survivinhigh, p63-, and BCL6 translocation. CD37 positivity predicted superior survival, abolishing the prognostic impact of high IPI and above biomarkers in GCB-DLBCL but not in ABC-DLBCL. Combining risk scores for CD37- status and ABC cell of origin with the IPI, defined as molecularly adjusted IPI for R-CHOP (M-IPI-R), or IPI plus immunohistochemistry (IHC; IPI+IHC) for CD37, Myc, and Bcl-2, significantly improved risk prediction over IPI alone. Gene expression profiling suggested that decreased CD20 and increased PD-1 levels in CD37- DLBCL, ICOSLG upregulation in CD37+ GCB-DLBCL, and CD37 functions during R-CHOP treatment underlie the pivotal role of CD37 status in clinical outcomes. In conclusion, CD37 is a critical determinant of R-CHOP outcome in DLBCL especially in GCB-DLBCL, representing its importance for optimal rituximab action and sustained immune responses. The combined molecular and clinical prognostic indices, M-IPI-R and IPI+IHC, have remarkable predictive values in R-CHOP-treated DLBCL.
Subject(s)
B-Lymphocytes/metabolism , Lymphoma, Large B-Cell, Diffuse/metabolism , Lymphoma, Large B-Cell, Diffuse/pathology , Antigens, CD20/genetics , Antigens, CD20/metabolism , Antigens, Neoplasm/genetics , Antigens, Neoplasm/metabolism , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Germinal Center/pathology , Humans , Lymphoma, Large B-Cell, Diffuse/drug therapy , Lymphoma, Large B-Cell, Diffuse/genetics , Male , Middle Aged , Models, Biological , Multivariate Analysis , Mutation/genetics , NF-kappa B/metabolism , Prognosis , Programmed Cell Death 1 Receptor/metabolism , Protein Transport , Proto-Oncogene Proteins c-myc/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Risk Factors , Survival Analysis , Tetraspanins/genetics , Tetraspanins/metabolism , Treatment Outcome , Tumor Suppressor Protein p53/geneticsABSTRACT
INTRODUCTION: Exercise training is recommended for improving health and protecting against the development of metabolic and cardiovascular pathologies. Combined resistance and aerobic exercise training (CRAE) has been shown to provide unique benefits in older adults with cardiovascular diseases. PURPOSE: We sought to determine the beneficial effects of CRAE in adolescent girls who are obese and hyperinsulinemic. METHODS: Forty adolescent girls who are obese (age 14.7 ± 1 years; BMI 30 ± 2) were randomly assigned to a "no exercise" (CON n = 20) or combined exercise group (EX n = 20). The EX group performed resistance and aerobic exercise for 12 weeks, 5 times per week. Exercise intensity was increased gradually, from 40 to 70% of heart rate reserve (HRR), every 4 weeks. The brachial-ankle pulse wave velocity (BaPWV), blood pressure (BP), heart rate (HR), blood leptin, adiponectin levels, and body composition were measured before and after the 12-week intervention. RESULTS: We observed that CRAE effectively reduced the body fat percentage, body weight, and waist circumference in the EX group (p < 0.05). After 12 weeks of training, subjects in the CRAE group maintained appropriate leptin and adiponectin levels and showed positive improvements of blood insulin, glucose, and insulin resistance parameters relative to baseline and to the CON group (p < 0.05). CONCLUSION: CRAE is a useful therapeutic method to alleviate metabolic risk factors in adolescent girls who are obese and hyperinsulinemic.
Subject(s)
Adiposity , Insulin Resistance , Obesity/therapy , Resistance Training/methods , Adiponectin/blood , Adolescent , Blood Glucose/metabolism , Blood Pressure , Female , Heart Rate , Humans , Insulin/blood , Leptin/bloodABSTRACT
Long-term musical training is widely reported to enhance music pitch perception. However, it remains unclear whether tone language experience influences the effect of long-term musical training on musical pitch perception. The present study addressed this question by testing 30 Cantonese and 30 non-tonal language speakers, each divided equally into musician and non-musician groups, on pitch height and pitch interval discrimination. Musicians outperformed non-musicians among non-tonal language speakers, but not among Cantonese speakers on the pitch height discrimination task. However, musicians outperformed non-musicians among Cantonese speakers, but not among non-tonal language speakers on the pitch interval discrimination task. These results suggest that the effect of long-term musical training on musical pitch perception is shaped by tone language experience and varies across different pitch perception tasks.
Subject(s)
Learning , Music , Phonetics , Pitch Perception , Asian People , Female , Humans , Male , Pitch Discrimination , Speech Acoustics , Young AdultABSTRACT
Nasal-type natural killer/T-cell lymphoma (NKTCL) is an aggressive disease characterized by frequent deletions on 6q, and constitutive activation of signal transducer and activator of transcription 3 (STAT3). Phosphorylation at Tyr705 activates STAT3, inducing dimerization, nuclear translocation, and DNA binding. In this study, we investigated whether receptor-type tyrosine-protein phosphatase κ (PTPRK), the only protein tyrosine phosphatase at 6q that contains a STAT3-specifying motif, negatively regulates STAT3 activation in NKTCL. PTPRK was highly expressed in normal NK cells but was underexpressed in 4 of 5 (80%) NKTCL cell lines and 15 of 27 (55.6%) primary tumors. Significantly, PTPRK protein expression was inversely correlated with nuclear phospho-STAT3(Tyr705) expression in NKTCL cell lines (P = .025) and tumors (P = .040). PTPRK restoration decreased nuclear phospho-STAT3(Tyr705) levels, whereas knockdown of PTPRK increased such levels in NKTCL cells. Phosphatase substrate-trapping mutant assays demonstrated the binding of PTPRK to STAT3, and phosphatase assays showed that PTPRK directly dephosphorylated phospho-STAT3(Tyr705). Restoration of PTPRK inhibited tumor cell growth and reduced the migration and invasion ability of NKTCL cells. Monoallelic deletion and promoter hypermethylation caused underexpression of PTPRK messenger RNA in NKTCL, and methylation of the PTPRK promoter significantly correlated with inferior overall survival (P = .049) in NKTCL patients treated with the steroid-dexamethasone, methotrexate, ifosfamide, l-asparaginase, and etoposide regimen. Altogether, our findings show that PTPRK underexpression leads to STAT3 activation and contributes to NKTCL pathogenesis.
Subject(s)
Lymphoma, Extranodal NK-T-Cell/metabolism , Nose Neoplasms/metabolism , Receptor-Like Protein Tyrosine Phosphatases, Class 2/metabolism , STAT3 Transcription Factor/metabolism , Tumor Suppressor Proteins/metabolism , Apoptosis , Caspases/metabolism , Cell Line, Tumor , Cell Nucleus/metabolism , Cell Proliferation , DNA Methylation , DNA Mutational Analysis , Down-Regulation , Female , Gene Deletion , Gene Knockdown Techniques , Humans , Lymphoma, Extranodal NK-T-Cell/genetics , Lymphoma, Extranodal NK-T-Cell/pathology , Male , Middle Aged , Neoplasm Invasiveness , Nose Neoplasms/genetics , Nose Neoplasms/pathology , Phosphorylation , Prognosis , Promoter Regions, Genetic , Protein Binding , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Neoplasm/genetics , RNA, Neoplasm/metabolism , Receptor-Like Protein Tyrosine Phosphatases, Class 2/deficiency , Receptor-Like Protein Tyrosine Phosphatases, Class 2/genetics , STAT3 Transcription Factor/chemistry , Tumor Suppressor Proteins/deficiency , Tumor Suppressor Proteins/geneticsABSTRACT
INTRODUCTION: Patient anatomy, practitioner experience, and surgical approach are all factors that influence implant accuracy. However, the relative importance of each factor is poorly understood. The present study aimed to identify which factors most critically determine implant accuracy to aid the practitioner in case selection for guided versus freehand surgery. METHODS: One practitioner's ideal implant angulation and position was compared with his achieved position radiographically for 450 implants placed using a conventional freehand method. The relative contribution of 11 demographic, anatomical, and surgical factors to the accuracy of implant placement was systematically quantified. DISCUSSION: The most important predictors of angulation and position accuracy were the number of adjacent implants placed and the tooth-borne status of the site. Immediate placement also significantly increased position accuracy, whereas cases with narrow sites were significantly more accurate in angulation. Accuracy also improved with the practitioner's experience. CONCLUSION: These results suggest tooth-borne, single-implant cases performed later in the practitioner's experience are most appropriate for freehand placement, whereas guided surgery should be considered to improve accuracy for multiple-implant cases in edentulous or partially edentulous sites.
Subject(s)
Clinical Competence , Cone-Beam Computed Tomography , Dental Implantation, Endosseous/methods , Dental Implants , Jaw, Edentulous, Partially/rehabilitation , Outcome and Process Assessment, Health Care , Surgery, Computer-Assisted/methods , Humans , Imaging, Three-Dimensional , SoftwareABSTRACT
FMS-like tyrosine kinase 3 (FLT3) is expressed in human hematopoietic stem and progenitor cells (HSPCs) but its role during embryogenesis is unclear. In acute myeloid leukemia (AML), internal tandem duplication (ITD) of FLT3 at the juxtamembrane (JMD) and tyrosine kinase (TKD) domains (FLT3-ITD(+)) occurs in 30% of patients and is associated with inferior clinical prognosis. TKD mutations (FLT3-TKD(+)) occur in 5% of cases. We made use of zebrafish to examine the role of flt3 in developmental hematopoiesis and model human FLT3-ITD(+) and FLT3-TKD(+) AML. Zebrafish flt3 JMD and TKD were remarkably similar to their mammalian orthologs. Morpholino knockdown significantly reduced the expression of l-plastin (pan-leukocyte), csf1r, and mpeg1 (macrophage) as well as that of c-myb (definitive HSPCs), lck, and rag1 (T-lymphocyte). Expressing human FLT3-ITD in zebrafish embryos resulted in expansion and clustering of myeloid cells (pu.1(+), mpo(+), and cebpα(+)) which were ameliorated by AC220 and associated with stat5, erk1/2, and akt phosphorylation. Human FLT3-TKD (D835Y) induced significant, albeit modest, myeloid expansion resistant to AC220. This study provides novel insight into the role of flt3 during hematopoiesis and establishes a zebrafish model of FLT3-ITD(+) and FLT3-TKD(+) AML that may facilitate high-throughput screening of novel and personalized agents.
Subject(s)
Hematopoiesis/genetics , Leukemia, Myeloid, Acute/genetics , Zebrafish Proteins/physiology , Zebrafish/physiology , fms-Like Tyrosine Kinase 3/physiology , Amino Acid Sequence , Animals , Animals, Genetically Modified , Conserved Sequence , Embryo, Nonmammalian , Humans , Molecular Sequence Data , Protein Structure, Tertiary/genetics , Sequence Homology, Amino Acid , Tandem Repeat Sequences , Transcriptome , Zebrafish/embryology , Zebrafish Proteins/chemistry , fms-Like Tyrosine Kinase 3/chemistryABSTRACT
This 1-year longitudinal study examined the role of Cantonese lexical tone sensitivity in predicting English reading comprehension and the pathways underlying their relation. Multiple measures of Cantonese lexical tone sensitivity, English lexical stress sensitivity, Cantonese segmental phonological awareness, general auditory sensitivity, English word reading, and English reading comprehension were administered to 133 Cantonese-English unbalanced bilingual second graders. Structural equation modeling analysis identified transfer of Cantonese lexical tone sensitivity to English reading comprehension. This transfer was realized through a direct pathway via English stress sensitivity and also an indirect pathway via English word reading. These results suggest that prosodic sensitivity is an important factor influencing English reading comprehension and that it needs to be incorporated into theoretical accounts of reading comprehension across languages.
Subject(s)
Comprehension/physiology , Language , Multilingualism , Phonetics , Asian People/ethnology , Awareness/physiology , Child , Hong Kong/ethnology , Humans , Language Tests , Longitudinal Studies , Pitch Discrimination/physiology , Reading , Transfer, Psychology/physiologyABSTRACT
Diffuse large B-cell lymphoma (DLBCL) is the most common form of lymphoma in adults. The disease exhibits a striking heterogeneity in gene expression profiles and clinical outcomes, but its genetic causes remain to be fully defined. Through whole genome and exome sequencing, we characterized the genetic diversity of DLBCL. In all, we sequenced 73 DLBCL primary tumors (34 with matched normal DNA). Separately, we sequenced the exomes of 21 DLBCL cell lines. We identified 322 DLBCL cancer genes that were recurrently mutated in primary DLBCLs. We identified recurrent mutations implicating a number of known and not previously identified genes and pathways in DLBCL including those related to chromatin modification (ARID1A and MEF2B), NF-κB (CARD11 and TNFAIP3), PI3 kinase (PIK3CD, PIK3R1, and MTOR), B-cell lineage (IRF8, POU2F2, and GNA13), and WNT signaling (WIF1). We also experimentally validated a mutation in PIK3CD, a gene not previously implicated in lymphomas. The patterns of mutation demonstrated a classic long tail distribution with substantial variation of mutated genes from patient to patient and also between published studies. Thus, our study reveals the tremendous genetic heterogeneity that underlies lymphomas and highlights the need for personalized medicine approaches to treating these patients.
Subject(s)
Genetic Heterogeneity , Lymphoma, Large B-Cell, Diffuse/genetics , Adult , Base Sequence , Cell Line, Tumor , Class I Phosphatidylinositol 3-Kinases , DNA Mutational Analysis , DNA, Neoplasm/genetics , Exome , Gene Expression , Genetic Variation , Humans , Lymphoma, Large B-Cell, Diffuse/drug therapy , Models, Molecular , Molecular Sequence Data , Molecular Targeted Therapy , Mutation , Oncogenes , Phosphatidylinositol 3-Kinases/chemistry , Phosphatidylinositol 3-Kinases/genetics , Protein Conformation , Proto-Oncogene Proteins c-kit/genetics , Receptor, Platelet-Derived Growth Factor alpha/genetics , Sequence Homology, Nucleic Acid , Signal Transduction/geneticsABSTRACT
MYC dysregulation, including MYC gene rearrangement and Myc protein overexpression, is of increasing clinical importance in diffuse large B-cell lymphoma (DLBCL). However, the roles of MYC and the relative importance of rearrangement vs overexpression remain to be refined. Gaining knowledge about the tumor biology associated with MYC dysregulation is important to understand the roles of MYC and MYC-associated biology in lymphomagenesis. In this study, we determined MYC rearrangement status (n=344) and Myc expression (n=535) in a well-characterized DLBCL cohort, individually assessed the clinical and pathobiological features of patients with MYC rearrangement and Myc protein overexpression, and analyzed the prognosis and gene expression profiling signatures associated with these MYC abnormalities in germinal center B-cell-like and activated B-cell-like DLBCL. Our results showed that the prognostic importance of MYC rearrangement vs Myc overexpression is significantly different in germinal center B-cell-like vs activated B-cell-like DLBCL. In germinal center B-cell-like DLBCL, MYC-rearranged germinal center B-cell-like DLBCL patients with Myc overexpression significantly contributed to the clinical, biological, and prognostic characteristics of the overall Myc-overexpressing germinal center B-cell-like DLBCL group. In contrast, in activated B-cell-like DLBCL, the occurrence, clinical and biological features, and prognosis of Myc overexpression were independent of MYC rearrangement. High Myc levels and Myc-independent mechanisms, either tumor cell intrinsic or related to tumor microenvironment, conferred significantly worse survival to MYC-rearranged germinal center B-cell-like DLBCL patients, even among Myc(high)Bcl-2(high) DLBCL patients. This study provides new insight into the tumor biology and prognostic effects associated with MYC dysregulation and suggest that detection of both MYC translocations and evaluation of Myc and Bcl-2 expression is necessary to predict the prognosis of DLBCL patients.
Subject(s)
Genes, myc/genetics , Lymphoma, Large B-Cell, Diffuse/genetics , Lymphoma, Large B-Cell, Diffuse/pathology , Proto-Oncogene Proteins c-myc/biosynthesis , Aged , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Cyclophosphamide/administration & dosage , Doxorubicin/administration & dosage , Female , Gene Rearrangement , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Kaplan-Meier Estimate , Lymphoma, Large B-Cell, Diffuse/drug therapy , Male , Middle Aged , Prednisone/administration & dosage , Prognosis , Proportional Hazards Models , Proto-Oncogene Proteins c-myc/genetics , Rituximab/administration & dosage , Transcriptome , Vincristine/administration & dosageABSTRACT
Nuclear factor-κB (NF-κB) is a transcription factor with a well-described oncogenic role. Study for each of five NF-κB pathway subunits was only reported on small cohorts in diffuse large B-cell lymphoma (DLBCL). In this large cohort (n=533) of patients with de novo DLBCL, we evaluated the protein expression frequency, gene expression signature, and clinical implication for each of these five NF-κB subunits. Expression of p50, p52, p65, RELB, and c-Rel was 34%, 12%, 20%, 14%, and 23%, whereas p50/p65, p50/c-Rel, and p52/RELB expression was 11%, 11%, and 3%, respectively. NF-κB subunits were expressed in both germinal center B-cell-like (GCB) and activated B-cell-like (ABC) DLBCL, but p50 and p50/c-Rel were associated with ABC-DLBCL. p52, RELB, and p52/RELB expressions were associated with CD30 expression. p52 expression was negatively associated with BCL2 (B-cell lymphoma 2) expression and BCL2 rearrangement. Although p52 expression was associated with better progression-free survival (PFS) (P=0.0170), singular expression of the remaining NF-κB subunits alone did not show significant prognostic impact in the overall DLBCL cohort. Expression of p52/RELB was associated with better overall survival (OS) and PFS (P=0.0307 and P=0.0247). When cases were stratified into GCB- and ABC-DLBCL, p52 or p52/RELB dimer expression status was associated with better OS and PFS (P=0.0134 and P=0.0124) only within the GCB subtype. However, multivariate analysis did not show p52 expression to be an independent prognostic factor. Beneficial effect of p52 in GCB-DLBC appears to be its positive correlation with CD30 and negative correlation with BCL2 expression. Gene expression profiling (GEP) showed that p52(+) GCB-DLBCL was distinct from p52(-) GCB-DLBCL. Collectively, our data suggest that DLBCL patients with p52 expression might not benefit from therapy targeting the NF-κB pathway.
Subject(s)
CD30 Ligand/metabolism , Lymphoma, Large B-Cell, Diffuse/metabolism , NF-kappa B p52 Subunit/metabolism , NF-kappa B/biosynthesis , Proto-Oncogene Proteins c-bcl-2/metabolism , Adult , Aged , Disease-Free Survival , Female , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Kaplan-Meier Estimate , Lymphoma, Large B-Cell, Diffuse/mortality , Lymphoma, Large B-Cell, Diffuse/pathology , Male , Middle Aged , Proportional Hazards Models , Signal Transduction/physiology , Tissue Array Analysis , TranscriptomeABSTRACT
Survivin, a member of the inhibitor of apoptosis protein family, is overexpressed in a variety of human neoplasms. The prognostic significance of survivin expression in diffuse large B-cell lymphoma patients treated with rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) is unclear. We used standard immunohistochemistry methods to quantify survivin expression in 463 patients with de novo diffuse large B-cell lymphoma who received the R-CHOP. Of the 463 patients, 269 (58%) had survivin overexpression with a cutoff of >25%, associated with an International Prognostic Index score of >2 (P=0.015), disease in ≥2 extranodal sites (P=0.011), and a high Ki-67 index (P<0.0001). Among patients with activated B cell-like disease, the overall survival rate of survivin-positive patients was significantly lower than that of survivin-negative patients (P=0.033); multivariate analysis confirmed that in these patients, survivin overexpression was an independent prognostic factor for survival. Among patients with wild-type p53 overexpression, the overall survival and progression-free survival rates of the survivin-positive group were significantly lower than those of the survivin-negative group (P=0.035 and P=0.04 respectively). In STAT3-positive patients, survivin overexpression was associated with significantly better survival. Among patients with activated B cell-like disease, survivin-positive compared with survivin-negative groups had significantly different gene expression signatures, including genes involved in mitosis or tumor cell proliferation. Our results indicate that survivin is an independent prognostic factor for poor outcome in patients with activated B cell-like disease treated with the R-CHOP regimen, and patients with survivin-positive activated B cell-like diffuse large B-cell lymphoma seem to benefit less from this treatment and may require additional novel agents.
Subject(s)
Biomarkers, Tumor/analysis , Inhibitor of Apoptosis Proteins/biosynthesis , Lymphoma, Large B-Cell, Diffuse/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal, Murine-Derived , Antineoplastic Combined Chemotherapy Protocols , Cyclophosphamide , Disease-Free Survival , Doxorubicin , Female , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Lymphoma, Large B-Cell, Diffuse/drug therapy , Lymphoma, Large B-Cell, Diffuse/mortality , Male , Middle Aged , Prednisone , Prognosis , Proportional Hazards Models , Rituximab , Survivin , Tissue Array Analysis , Transcriptome , Vincristine , Young AdultABSTRACT
MOTIVATION: Combinatorial therapies play increasingly important roles in combating complex diseases. Owing to the huge cost associated with experimental methods in identifying optimal drug combinations, computational approaches can provide a guide to limit the search space and reduce cost. However, few computational approaches have been developed for this purpose, and thus there is a great need of new algorithms for drug combination prediction. RESULTS: Here we proposed to formulate the optimal combinatorial therapy problem into two complementary mathematical algorithms, Balanced Target Set Cover (BTSC) and Minimum Off-Target Set Cover (MOTSC). Given a disease gene set, BTSC seeks a balanced solution that maximizes the coverage on the disease genes and minimizes the off-target hits at the same time. MOTSC seeks a full coverage on the disease gene set while minimizing the off-target set. Through simulation, both BTSC and MOTSC demonstrated a much faster running time over exhaustive search with the same accuracy. When applied to real disease gene sets, our algorithms not only identified known drug combinations, but also predicted novel drug combinations that are worth further testing. In addition, we developed a web-based tool to allow users to iteratively search for optimal drug combinations given a user-defined gene set. AVAILABILITY: Our tool is freely available for noncommercial use at http://www.drug.liuzlab.org/. CONTACT: zhandong.liu@bcm.edu SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.