Burkitt Lymphoma Patients Research Articles

Cytokine-Induced Killer Cells in Combination with Heat Shock Protein 90 Inhibitors Functioning via the Fas/FasL Axis Provides Rationale for a Potential Clinical Benefit in Burkitt's lymphoma.

Constant efforts are being made to develop methods for improving cancer immunotherapy, including cytokine-induced killer (CIK) cell therapy. Numerous heat shock protein (HSP) 90 inhibitors have been assessed for antitumor efficacy in preclinical and clinical trials, highlighting their individual prospects for targeted cancer therapy. Therefore, we tested the compatibility of CIK cells with HSP90 inhibitors using Burkitt's lymphoma (BL) cells. Our analysis revealed that CIK cytotoxicity in BL cells was augmented in combination with independent HSP90 inhibitors 17-DMAG (17-dimethylaminoethylamino-17-demethoxygeldanamycin) and ganetespib. Interestingly, CIK cell cytotoxicity did not diminish after blocking with NKG2D (natural killer group 2, member D), which is a prerequisite for their activation. Subsequent analyses revealed that the increased expression of Fas on the surface of BL cells, which induces caspase 3/7-dependent apoptosis, may account for this effect. Thus, we provide evidence that CIK cells, either alone or in combination with HSP90 inhibitors, target BL cells via the Fas-FasL axis rather than the NKG2D pathway. In the context of clinical relevance, we also found that high expression of HSP90 family genes (HSP90AA1, HSP90AB1, and HSP90B1) was significantly associated with the reduced overall survival of BL patients. In addition to HSP90, genes belonging to the Hsp40, Hsp70, and Hsp110 families have also been found to be clinically significant for BL survival. Taken together, the combinatorial therapy of CIK cells with HSP90 inhibitors has the potential to provide clinical benefits to patients with BL.

Chromosomal Aberration t(14;17)(q32;q21) Simultaneously Activates HOXB5 and miR10a in Triple-Hit B-Cell Lymphoma.

BCL2, BCL6 and MYC are major oncogenes in B-cell lymphoma. Their aberrant activation frequently occurs via chromosomal translocations which juxtapose light or heavy chain immunoglobulin (IG) genes to BCL2 and MYC or fuse diverse partner genes with BCL6. So-called double-hit lymphomas usually carry BCL2 and MYC rearrangements, while triple-hit lymphomas additionally bear BCL6-fusions. All these translocations are of diagnostic relevance and usually denote poor prognosis. Here, we genomically characterized classic follicular lymphoma (FL) cell line SC-1, thereby identifying t(14;18)(q32;q21) juxtaposing IGH and BCL2, t(8;14)(q24;q32) juxtaposing IGH and MYC, and t(3;3)(q25;q27) fusing MBNL1 to BCL6. In addition, we found that SC-1 carries a novel chromosomal rearrangement, t(14;17)(q32;q21), which, though present at establishment, has remained unreported until now. We further show that t(14;17)(q32;q21) juxtaposes IGH with the HOXB gene cluster at 17q21 and affect the oncogenic activation of both homeobox gene HOXB5 and neighboring micro-RNA gene miR10a. Moreover, we detected aberrant overexpression of HOXB5 in subsets of Burkitt lymphoma, FL, and multiple myeloma patients, confirming the clinical relevance of its deregulation. In SC-1, HOXB5 activation was additionally supported by co-expression of hematopoietic stem cell factor ZNF521, indicating an aberrant impact in cell differentiation. Functional investigations showed that HOXB5 represses the apoptotic driver BCL2L11 and promotes survival in the presence of etoposide, and that miR10a inhibits BCL6 and may thus play an oncogenic role in later stages of lymphomagenesis. Collectively, we characterize triple-hit B-cell line SC-1 and identify the aberrant expression of HOXB5 and miR10a, both novel oncogenes in B-cell lymphoma.

Worldwide Prevalence of Epstein–Barr Virus in Patients with Burkitt Lymphoma: A Systematic Review and Meta-Analysis

Burkitt lymphoma (BL) is a form of B-cell malignancy that progresses aggressively and is most often seen in children. While Epstein–Barr virus (EBV) is a double-stranded DNA virus that has been linked to a variety of cancers, it can transform B lymphocytes into immortalized cells, as shown in BL. Therefore, the estimated prevalence of EBV in a population may assist in the prediction of whether this population has a high risk of increased BL cases. This systematic review and meta-analysis aimed to estimate the prevalence of Epstein–Barr virus in patients with Burkitt lymphoma. Using the appropriate keywords, four electronic databases were searched. The quality of the included studies was assessed using the Joanna Briggs Institute’s critical appraisal tool. The results were reported as percentages with a 95% confidence interval using a random-effects model (CI). PROSPERO was used to register the protocol (CRD42022372293), and 135 studies were included. The prevalence of Epstein–Barr virus in patients with Burkitt lymphoma was 57.5% (95% CI: 51.5 to 63.4, n = 4837). The sensitivity analyses demonstrated consistent results, and 65.2% of studies were of high quality. Egger’s test revealed that there was a significant publication bias. EBV was found in a significantly high proportion of BL patients (more than 50% of BL patients). This study recommends EBV testing as an alternative for predictions and the assessment of the clinical disease status of BL.

17th International Conference on Malignant Lymphoma, Palazzo dei Congressi, Lugano, Switzerland, 13 - 17 June, 2023.

Introduction: Burkitt lymphoma (BL) is a rare but highly aggressive B-cell non-Hodgkin lymphoma. BL exhibits a characteristic immunophenotype that is positive for pan-B cell markers and CD10. The genetic hallmark of BL is the translocation of the MYC oncogene under the regulation of an immunoglobulin (IG) heavy or light chain enhancer, resulting in MYC protein overexpression. Notably, MYC translocation by itself is not sufficient for BL oncogenesis and a variety of cancer genes are recurrently mutated. BL can be divided epidemiologically but also, more recently, genetically based on driver mutations including DGG-BL (DDX3X, GNA13, and GNAI2), IC-BL (ID3 and CCND3), and Q53-BL (quiet TP53). Despite high survival rates, pediatric BL patients suffer from long-term side effects and relapses are usually fatal. In order to develop more targeted and less toxic therapies, a better understanding is needed of the ethology of the disease. Therefore, our aim is to characterise the cell-of-origin (COO) and dissect the life history of BL subtypes, by pinpointing when during tumorigenesis somatic mutations play a role and by identifying the rate-limiting steps of malignant transformation. Method: We collected single-cell suspensions of BL patient samples, including lymph node biopsies, bone marrow aspirates, as well as ascites and pleural fluid. To perform flow cytometry, single cells were stained with DAPI and a panel of antibodies: CD10/CD45/CD19 or CD10/CD3/CD20. Live B cells were separated with the DAPI-CD45+ CD19+ or DAPI-CD3-CD20+ phenotype. Subsequently, CD10+ B cells and CD10- B cells were sorted in 96-well plates (Figure 1). To confirm the presence or absence of the IG::MYC translocation a PCR was perfomed using patient-specific primers that flank the translocation locus. Whole genome amplification was carried out on the DNA of single cells using the Primary Template-directed Amplification (PTA) technique that was subsequently whole genome sequenced. Results: From a bone marrow sample of a 4-year-old female BL patient we found that 1% of immune cells were CD10+ B cells, while 17% of B cells were negative for the CD10 marker (Figure 2A). In the lymph node sample from the same patient, we found that 87% of B cells were CD10+ and 9% were CD10- (Figure 2B). PCR confirmed the MYC translocation in 2/6 CD10+ and 0/6 CD10- bone marrow-derived B cells (Figure 3). Keywords: Genomics, Epigenomics, and Other -Omics, Non-Hodgkin (Pediatric, Adolescent, and Young Adult), Tumor Biology and Heterogeneity No conflicts of interests pertinent to the abstract.

Features of human acquired immunodeficiency virus-associated non-Hodgkin’s lymphoma

Abstract OBJECTIVE: The objective of this study was to investigate the clinical characteristics, imaging manifestations, and prognosis of patients with acquired immunodeficiency syndrome (AIDS)-related non-Hodgkin’s lymphoma (NHL). PATIENTS AND METHODS: This retrospective study included 92 patients with AIDS-related NHL (ARL), who were treated at the Central South Hospital of Wuhan University between January 2005 and March 2022. Patients were divided into three groups according to their pathological type: diffuse large B-cell lymphoma (DLBCL), Burkitt lymphoma (BL), and plasmablastic lymphoma (PBL). Their clinical characteristics and imaging data were compared. In addition, some computed tomography (CT) features of the tumors were analyzed and summarized. SPSS 26.0 was used for statistical analysis. The prognostic factors were analyzed using the Kaplan–Meier method, Cox proportional risk regression model, and receiver operating characteristic curve. RESULTS: Among the 92 cases, 68 were DLBCL, 19 were BL, and five were PBL. BL patients had a higher risk profile than DLBCL and PBL patients. Most of the tumors had unclear borders, uneven densities on plain and enhanced CT scans, and signs of fusion and necrosis. The analyses indicated that the International Prognostic Index (IPI) score (odd ratio [OR] =15.699, 95% confidence interval [CI] =1.828–134.829, P = 0.012) and Eastern Cooperative Oncology Group (ECOG) score (OR = 28.869, 95% CI = 3.015–276.395, P = 0.004) were independent prognostic indicators of the overall survival. CONCLUSIONS: ARL is a heterogeneous and aggressive disease with a poor prognosis. Compared with DLBCL or PBL patients, BL patients have higher risk features. IPI and ECOG scores can effectively predict the prognosis of ARL.

A national analysis of Burkitt lymphoma in the Hispanic community.

e18818 Background: Burkitt Lymphoma (BL) is an aggressive disease that accounts for 1% to 5% of non-Hodgkin B-cell lymphoma. Outcomes of the disease relies heavily on prompt diagnosis, evaluation, and management by multi-disciplinary healthcare team. Hence racial and ethnic inequities can play a role in the prognosis of BL. This study used national population-based analysis to explore the disparities between Hispanics (HI) and Non-Hispanics (NH) with BL in management and survival. Methods: Data were analyzed on Burkitt Lymphoma patients in the United States reported to the Surveillance, Epidemiology, and End Results (SEER) database. SEER contains the most comprehensive population-based cancer information in the U.S., covering approximately 27% of the total US population, and up to 36% of HI alone. Racial groups analyzed included NH, HI, blacks, and Asians/Pacific Islanders. Patient characteristics, age-adjusted incidence rate, and survival rate were compared across ethnic groups. Stratification by age, gender, and stage at diagnosis was considered. Kaplan-Meier and Cox regression analyses were used to compare overall survival (OS). Multivariate analysis and propensity score matching were performed with adjustment for age, stage and B-symptoms. Results: Of 6214 of BL patients, 19% were HI, and 80.4% NH. 70% of HI were male, compared to 73% of NH. The majority of HI (52%) and NH (41%) were diagnosed in the age bracket of < 40 (p = < 0.001). The median age at diagnosis was 39 for HI vs. 46 for NH (p < 0.001). The majority of HI (29%) were diagnosed between years (2010-2014), compared to majority of NH (28%) who were diagnosed between years (2005-2009) (p = < 0.001). Most of HI and NH were whites (96% vs 77%), followed by blacks (2% vs 12%). For stage, the majority of HI (35%) and NH (38%) were stage IV (p = < 0.001). In terms of radiation, 7% of HI received it, compared to 7% of NH (p = 0.51). Finally, the survival probability at 2, 5 and 10 years of HI vs NH were (0.619 vs 0.589), (0.608 vs 0.548), and (0.569 vs 0.492), respectively. The median survival time was 16.8 years for HI, vs 9.1 years for NH; and there was overall survival difference favoring HI with (p = < 0.0001) On multivariate analysis, those patients who were older than 80 and between 60 to 80 had worse OS compared to those younger than 60, with HR 6.48 (95% CI: 5.5 – 7.6 ) and 2.7 (95% CI: 2.4 – 3) respectively. Those who were at stage III and IV, had worse OS than those at early stage (I/II) with HR 1.4 (95% CI: 1.1 – 1.7) and HR 2.5 (95% CI: 2.1 – 2.9), respectively. Conclusions: The data analysis demonstrates BL to favor HI over NH in survival and outcome. This analysis illustrates that ethnicity does not alter oncological prognosis in BL for HI in the US. Exploration of etiologies of BL, as in sporadic, endemic, or immunodeficiency-related, can provide an improved understanding of our observation. Assessing each group's social determinants of health is also warranted to further define this significant difference in survival.

Abstract 33: Epidemiology, Diagnosis, and Outcomes of Pediatric Burkitt Lymphoma Patients Treated at Bugando Medical Centre in Mwanza, Tanzania

Abstract Purpose: Despite the significant improvement in outcomes over the last few decades for the treatment of pediatric Burkitt lymphoma, outcomes in sub-Saharan Africa remain poor, with an approximately 50% survival rate. This disparity is likely multifactorial and significant work remains to improve these outcomes in low resource settings. As a first step in attempting to improve these disparate outcomes at our hospital, Bugando Medical Centre (BMC), in Mwanza, Tanzania, we aim to improve the understanding of the presentation, diagnosis, and outcomes with the current standard of care therapy at our site. We propose that a better understanding of the current nature of care for these patients at our site will allow for more informed future interventions aimed at improving outcomes. Methods: Historical patient data were abstracted for pediatric patients with a diagnosis of Burkitt lymphoma treated at BMC from 2016-2022. Patients’ initial presentations (e.g. site of disease), means of diagnosis, treatment completion rate, and outcomes (if available) were analyzed. Results: Data were available on 109 patients with a diagnosis of Burkitt lymphoma between 2016-2022. Patients were on average 7.7 years old at presentation. We observed a 2:1 male to female ratio. We observed a significant proportion of abdominal disease with 58.7% presenting with abdominal disease (either alone or in combination) at initial diagnosis. There were 91% of patients who were deemed INCTR ‘high risk’ at diagnosis. There was a notable improvement in the percent of patients diagnosed with a biopsy with 46% in 2016 and 100% in 2022. Outcomes were poor but were difficult to assess with clarity due to a high rate of abandonment. Within those limitations, we observed a 1-year overall survival, of patients through 2021 with known outcomes, of 50.2% and a 1-year event free survival of 34.1% (including abandoment as an event). Conclusion: Overall, in our patients we note epidemiology consistent with known data for endemic Burkitt lymphoma. Our patient population includes a significant proportion of abdominal and/or high-risk disease. We demonstrate overall poor outcomes with a high degree of treatment abandonment. These data suggest that improvement in treatment efficacy and treatment adherence may improve outcomes. Citation Format: Hutton Chapman, Paul S. Ntemi, Jacqueline Kamanga, Judith Paschal, Heronima J. Kashaigili, Kristin Schroeder. Epidemiology, Diagnosis, and Outcomes of Pediatric Burkitt Lymphoma Patients Treated at Bugando Medical Centre in Mwanza, Tanzania [abstract]. In: Proceedings of the 11th Annual Symposium on Global Cancer Research; Closing the Research-to-Implementation Gap; 2023 Apr 4-6. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(6_Suppl):Abstract nr 33.

Subgrouping of Burkitt lymphoma variants by DNA methylation is driven by an EBV‐associated epigenotype

Introduction: Burkitt lymphoma (BL) is an aggressive mature B-cell lymphoma, which traditionally has been separated into three epidemiologic variants: endemic (eBL), sporadic (sBL) and immunodeficiency-associated BL (iBL). This subgrouping is strongly confounded by EBV-infection. Indeed, there is evidence from molecular studies that subtyping of BL based on EBV status might better reflect the pathogenetic heterogeneity than epidemiology. As EBV is known to influence epigenetic regulation, we here aimed at a comparative DNA methylation (DNAme) profiling of BL variants with respect to their geographic origin and EBV status. Methods: We collected DNAme profiles (Infinium HumanMethylation450 and Infinium MethylationEPIC BeadChip) of 116 BL patients (80 sBL: 7 EBV+; 29 eBL: 27 EBV+; 7 iBL: 4 EBV+), 17 BL cell lines and 6 EBV-transformed LCLs. For group determination unsupervised clustering algorithms (K-means, PGMRA, UMAP) were applied. To investigate potential consequences of EBV-associated DNAme we performed a protein-protein interaction network analysis on genes within the EBV-specific DNAme pattern. Moreover, we mined gene expression values from RNAseq in 21 EBV- sBL and 5 germinal-center B-cell populations. Results: Unsupervised clustering algorithms revealed two distinct DNAme phenotypes, which differentiate EBV+ and EBV- BL based on 1,266 CpGs. This separation is accompanied by a characteristic hypermethylation in EBV+ BLs. Additionally, we identified a subgroup of EBV+ BL with a similar DNAme pattern like the LCLs, possibly indicating latency phase differences within EBV+ BLs. Investigation of the EBV-specific DNAme pattern revealed a network with UBC as a key interactor, indicating the potential importance of the ubiquitin-proteasome system (UPS) in EBV-induced lymphomagenesis. Among genes differentially methylated between EBV+ and EBV- BL, 19 genes have been reported as recurrently mutated in BL. All except 3 of these genes are expressed in sBL and germinal-center B-cells. All these genes were significantly hypermethylated within regulatory regions in EBV+ BLs (σ/σmax = 0.4, q ≤ 0.01), including genes with a lower mutational frequency in EBV+ versus EBV- BLs. Conclusion: The findings of this study show the EBV status to be strongly associated with DNAme subgroups in BL, supporting the subtyping of BL variants based on their EBV status rather than their geographic origin. Moreover, the pattern of DNAme in EBV+ BL might suggest epigenetic silencing and deregulated ubiquitination as means alternative to gene mutation to be involved in the pathogenesis of EBV+ BL. Keywords: Aggressive B-cell non-Hodgkin lymphoma, Genomics, Epigenomics, and Other -Omics, Pathology and Classification of Lymphomas No conflicts of interests pertinent to the abstract.

17th International Conference on Malignant Lymphoma, Palazzo dei Congressi, Lugano, Switzerland, 13 - 17 June, 2023.

Introduction: Burkitt lymphoma (BL) is a highly aggressive B-cell lymphoma; because of its fast growing rate, it often represents a clinical emergency. Intensive treatment approaches are required for adult BL, although a univocal standard of care still does not exist. The use of frontline autologous transplantation (ASCT) is debated. Methods: Between 2004 and 2020, 50 HIV-negative BL patients were treated with the Berlin-Frankfurt-Münster (BFM) protocol at our institution. Treatment plan consisted of 3 blocks, A (ifosfamide, vincristine, methotrexate, etoposide, cytarabine), B (vincristine, cyclophosphamide, methotrexate, doxorubicin) and C (vindesine, methotrexate, etoposide, cytarabine), each repeated twice, every 28 days. Patients elder than 60 years did not receive block C, thus blocks A and B were repeated 3 times. Rituximab was given at day 1 each block. Central nervous system (CNS) prophylaxis with intrathecal cytarabine, methotrexate and dexamethasone was given once per each block. Autologous stem cells were harvested after the 4th or 5th cycles, with reinfusion (ASCT) at the end of the 6-blocks after BEAM (carmustine, etoposide, cytarabine, melphalan) conditioning, when feasible. Results: Median age at onset was 38 years (range 16–72); 387 patients were male and 12 female. Stage III-IV disease was observed in 82% of cases; bulky disease occurred in 44% of the patients, with B-symptoms in 38%. Two patients did not receive rituximab because of adverse reaction and early death. Intrathecal prophylaxis was given in 96% of patients. Stem cell harvest was performed in 70% of patients, who all received a subsequent ASCT. The full 6-blocks treatment was completed in 70% of the patients; 8% received 5 cycles and 22% received ≤3 cycles. Early treatment interruption occurred because of disease progression (12%), toxicity (8%), death (4%) or other causes (4%). The overall response rate was 74%, with a complete response rate of 60%. Three patients could not be evaluated because of early progression/death. Ten-year overall survival and progression-free survival were 83.7% and 76.0%, respectively, with both curves exhibiting a plateau. Likewise, 10-year disease-free survival was 80.3%. Eight patients had died because of disease progression (3 patients), infection or sepsis (4 patients) or cardiac arrest (1 patient). Grade 3–4 neutropenia, thrombocytopenia, anemia and mucositis were seen in 96%, 60%, 32% and 24% of patients, respectively. Infections occurred in 60% of patients, with grade 4 and fatal sepsis in 14% and 8% of cases, respectively. Methotrexate-related hepatic and renal toxicity occurred in 16% and 12% of patients, respectively, with complete recovery in all cases. Keywords: Chemotherapy, Immunotherapy, Stem Cell Transplant No conflicts of interests pertinent to the abstract.

Burkitt lymphoma in patients with HIV infection: results of a Russian multicenter study

Введение. Лимфома Беркитта (ЛБ) ― высокоагрессивная В-клеточная неходжкинская лимфома, составляет до 40% лимфом у пациентов с ВИЧ-инфекцией. Широкое применение антиретровирусной терапии (АРВТ) способствовало улучшению результатов противоопухолевой химиотерапии (ПХТ) лимфом на фоне ВИЧ-инфекции, в том числе ЛБ. Терапии ЛБ в РФ посвящено только несколько работ, а публикаций о ЛБ у пациентов с ВИЧ-инфекцией нет. Цель работы: изучить клинико-эпидемиологические характеристики и оценить результаты терапии ЛБ у пациентов с ВИЧ-инфекцией в РФ. Материалы и методы. В исследование было включено 37 пациентов с ЛБ на фоне ВИЧ-инфекции, проходивших лечение в 10 центрах РФ в период с 2010 по 2021 гг. Результаты. ЛБ у пациентов с ВИЧ-инфекцией диагностируется в молодом возрасте, с медианой 37 лет (21–58 лет), чаще у мужчин (75,7%), в распространенной стадии (IV стадия Ann Arbor ― 64,7%) и с экстралимфатическими проявлениями (73,5%), включая поражение центральной нервной системы (ЦНС) (16,1%). Основная терапия: EPOCH-подобные курсы (54,1%), блоковые схемы (32,4%). У 76% пациентов противоопухолевая ХТ включала ритуксимаб, у 91,4% ― одновременно с АРВТ. Медиана количества курсов терапии составила 4 (1–8). Общая выживаемость (ОВ) в течение 1 года составила 64% (95% ДИ 38–82%), выживаемость без прогрессирования (ВБП) ― 59% (95% ДИ 34–77%). Поражение ЦНС (p=0.0064), и проведение ПХТ без АРВТ ухудшает ОВ (p=0,00016) и ВБП (p=0,00012). Заключение. Для улучшения результатов терапии и прогноза необходимы проспективные м Введение. Лимфома Беркитта (ЛБ) ― высокоагрессивная В-клеточная неходжкинская лимфома, составляет до 40% лимфом у пациентов с ВИЧ-инфекцией. Широкое применение антиретровирусной терапии (АРВТ) способствовало улучшению результатов противоопухолевой химиотерапии (ПХТ) лимфом на фоне ВИЧ-инфекции, в том числе ЛБ. Терапии ЛБ в РФ посвящено только несколько работ, а публикаций о ЛБ у пациентов с ВИЧ-инфекцией нет. Цель работы: изучить клинико-эпидемиологические характеристики и оценить результаты терапии ЛБ у пациентов с ВИЧ-инфекцией в РФ. Материалы и методы. В исследование было включено 37 пациентов с ЛБ на фоне ВИЧ-инфекции, проходивших лечение в 10 центрах РФ в период с 2010 по 2021 гг. Результаты. ЛБ у пациентов с ВИЧ-инфекцией диагностируется в молодом возрасте, с медианой 37 лет (21–58 лет), чаще у мужчин (75,7%), в распространенной стадии (IV стадия Ann Arbor ― 64,7%) и с экстралимфатическими проявлениями (73,5%), включая поражение центральной нервной системы (ЦНС) (16,1%). Основная терапия: EPOCH-подобные курсы (54,1%), блоковые схемы (32,4%). У 76% пациентов противоопухолевая ХТ включала ритуксимаб, у 91,4% ― одновременно с АРВТ. Медиана количества курсов терапии составила 4 (1–8). Общая выживаемость (ОВ) в течение 1 года составила 64% (95% ДИ 38–82%), выживаемость без прогрессирования (ВБП) ― 59% (95% ДИ 34–77%). Поражение ЦНС (p=0.0064), и проведение ПХТ без АРВТ ухудшает ОВ (p=0,00016) и ВБП (p=0,00012). Заключение. Для улучшения результатов терапии и прогноза необходимы проспективные многоцентровые исследования по лечению ЛБ у пациентов с ВИЧ. ногоцентровые исследования по лечению ЛБ у пациентов с ВИЧ.

Increased Frequency of Mosaic Chromosomal Alterations in Peripheral Blood Samples of Sub-Saharan African Children with Endemic Burkitt Lymphoma

Introduction: Burkitt lymphoma (BL) is an aggressive B-cell lymphoma with reciprocal IG∷MYC translocations and accounts for 50-75% of childhood cancers in sub-Saharan Africa. Mosaic chromosomal alterations (mCAs) are large, somatically acquired structural chromosomal alterations that are clonal and observed in detectable fractions of circulating mononuclear cells. mCAs have been linked to increased hematologic cancer risk, but their association with BL, a mononuclear B cell tumor, is unknown. We hypothesized that the frequency and distribution of mCAs in peripheral leukocytes would be elevated in children with BL, potentially serving as a biomarker of chromosomal instability relevant to BL risk. Methods: We investigated peripheral leukocyte DNA extracted from children enrolled in the Epidemiology of Burkitt Lymphoma in East African Children and Minors (EMBLEM) study (2010-2016) and the Infections and Childhood Cancer case-control study conducted in Malawi (2005-2010). We used genome-wide single nucleotide polymorphism (SNP) array data to investigate the frequency, type, and distribution of mCAs >2Mb in size detected in peripheral leukocytes of 931 pediatric BL cases with 3,645 healthy children in Uganda, Tanzania, and Kenya, and with 177 non-BL pediatric cancers in Malawi. Eagle2 and SHAPEIT4 software were used for phasing to infer haplotypes for SNP array data and WGS data. MoChA (v2014-05-14) was used to detect mCAs. Parallel analysis using similar methods was performed on whole genome sequences (WGS) from paired tumor-normal blood samples from two Ugandan BL patients from the BL Genome Sequencing Project (BLGSP) and from paired BL- and lymphoblastoid-derived cell lines. Results: Most samples (92%) were from the EMBLEM study, whereas 8% were from Malawi. The mean age of the BL cases and controls was similar (~7.4 years in both, P=0.60). Table 1 shows detected autosomal mCAs for BL cases and controls by country. Overall, a total of 250 autosomal mCAs were detected in 78 (8.4%) of the 931 BL cases. By comparison, a total of 188 autosomal mCAs were detected in 131 (3.4%) of the 3822 controls. Autosomal mCAs were detected in cell fractions ranging from 0.5% to 99.2% (Figure S1). The average number of autosomal mCAs per person (i.e., total of mCAs detected/number of individuals with mCAs detected) was higher in the BL cases compared to controls (3.21 [SD 3.24] versus 1.44 [SD 2.31], P-value=4.50×10-5. The higher frequency of mCAs in blood samples of children with BL compared to controls was independent of age, sex, P falciparum status, and country (OR=2.8, 95% CI=2.06-3.81, P-value=5.70×10-11, Table 1. mCAs on the X chromosome in girls were also associated with BL (5% versus 1.7%, OR=3.12, 95% CI=1.47-6.29, P-value=1.65×10-3). We did not observe an association for mCAs on the Y chromosome in boys. Analysis of paired tumor-normal samples confirmed the presence of the IG∷MYC translocation in tumor, but the same pipelines did not detect the translocation in the corresponding normal blood sample. In informative tumor-normal cases, some mCAs were only detected in tumor, others were detected in both tumor and normal blood, whereas others were detected mCAs in normal only suggesting some mCAs in blood could arise from pre-BL clones. mCAs only observed in BL cases were predominantly gains on chromosome 1q and 8 (Figure 1) which contain major drivers of Burkitt lymphomagenesis including PLEKHO1, MCL1, PSMB4, ILF2, HAX1, ATP8B2 and CKS1B.Conclusion: We report a high frequency of mCAs in healthy sub-Saharan African children and even higher frequency in pediatric BL cases. The mCAs in children with BL clustered on chromosomes 1q and 8 in regions that overlap with several significantly mutated BL genes, suggesting that mCAs may be potential biomarkers important in the natural history of BL. Using paired tumor-normal sample WGS data, we report both similar and unique mCAs in the paired samples suggesting pre-BL clones in blood. These methods are scalable to large cohorts with SNP array data to investigate health effects associated with mCAs in Africa. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 regimen in the treatment of pediatric Burkitt lymphoma

Objective: To analyze the clinical characteristics of children with Burkitt lymphoma (BL) and to summarize the mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 (CNCL-B-NHL-2017) regimen. Methods: Clinical features of 436 BL patients who were ≤18 years old and treated with the CNCL-B-NHL-2017 regimen from May 2017 to April 2021 were analyzed retrospectively. Clinical characteristics of patients at disease onset were analyzed and the therapeutic effects of patients with different clinical stages and risk groups were compared. Survival analysis was performed by Kaplan-Meier method, and Cox regression was used to identify the prognostic factors. Results: Among 436 patients, there were 368 (84.4%) males and 68 (15.6%) females, the age of disease onset was 6.0 (4.0, 9.0) years old. According to the St. Jude staging system, there were 4 patients (0.9%) with stage Ⅰ, 30 patients (6.9%) with stage Ⅱ, 217 patients (49.8%) with stage Ⅲ, and 185 patients (42.4%) with stage Ⅳ. All patients were stratified into following risk groups: group A (n=1, 0.2%), group B1 (n=46, 10.6%), group B2 (n=19, 4.4%), group C1 (n=285, 65.4%), group C2 (n=85, 19.5%). Sixty-three patients (14.4%) were treated with chemotherapy only and 373 patients (85.6%) were treated with chemotherapy combined with rituximab. Twenty-one patients (4.8%) suffered from progressive disease, 3 patients (0.7%) relapsed, and 13 patients (3.0%) died of treatment-related complications. The follow-up time of all patients was 24.0 (13.0, 35.0) months, the 2-year event free survival (EFS) rate of all patients was (90.9±1.4) %. The 2-year EFS rates of group A, B1, B2, C1 and C2 were 100.0%, 100.0%, (94.7±5.1) %, (90.7±1.7) % and (85.9±4.0) %, respectively. The 2-year EFS rates was higher in group A, B1, and B2 than those in group C1 (χ2=4.16, P=0.041) and group C2 (χ2=7.21, P=0.007). The 2-year EFS rates of the patients treated with chemotherapy alone and those treated with chemotherapy combined with rituximab were (79.3±5.1)% and (92.9±1.4)% (χ2=14.23, P<0.001) respectively. Multivariate analysis showed that stage Ⅳ (including leukemia stage), serum lactate dehydrogenase (LDH)>4-fold normal value, and with residual tumor in the mid-term evaluation were risk factors for poor prognosis (HR=1.38,1.23,8.52,95%CI 1.05-1.82,1.05-1.43,3.96-18.30). Conclusions: The CNCL-B-NHL-2017 regimen show significant effect in the treatment of pediatric BL. The combination of rituximab improve the efficacy further.

Expression of TCF3 in Burkitt's Lymphoma and Its Proliferative Effect and Prognostic Significance

To observe the mutation and expression of TCF3 gene in Burkitt's lymphoma (BL), and explore its effect on the proliferation of BL cells and clinical efficacy and prognosis. The mutation and expression of TCF3 in tumor tissues from BL patients were observed by the second-generation sequencing and real-time quantitative PCR. The proliferation and apoptosis of lymphoma cells after TCF3 knocked down were observed by siRNA interference technique and CCK-8 method. Survival analysis was used to observe the relationship between TCF3 mutation and the treatment efficacy and prognosis of BL patients. There were high frequency mutation rate (mutation rate was 23.7%) and high expression of TCF3 in BL patients. After TCF3 knocked down, cell proliferation was inhibited and apoptosis was promoted. In TCF3-siRNA group and control group, the cell proliferation rate at 48 h was (50.2±5.9)% and (96.6±11.4)%, and apoptosis rate was 30.1% and 1.5%, respectively, which showed significantly different between the two groups (P<0.001, P=0.005). The complete remission rate of patients with TCF3 mutation was low. The complete remission rate of mutant group and wild-type group was 44.4% and 82.8%, respectively (P=0.023). The 2-year progression-free survival rate and overall survival rate of the patients with TCF3 mutation was 55.6% and 61.0%, respectively, which was lower than 83.2% and 85.2% of the patients without mutation, but the differences were not statistically significant. There are mutation and abnormal expression of TCF3 in patients with BL. Patients with TCF3 mutations have low remission rate and poor prognosis.

ABCL-400 Adult Burkitt Lymphoma: An Institutional Experience With Uniform DA-EPOCH-R Protocol

DA-EPOCH-R (dose-adjusted etoposide, doxorubicin, cyclophosphamide, vincristine, prednisolone, and rituximab) is one of the standard chemotherapeutic regimens for Burkitt lymphoma. This study aimed to evaluate the safety and efficacy of DA-EPOCH-R in adult Burkitt lymphoma in an Indian context. This retrospective study included 16 patients with adult Burkitt lymphoma who received uniform DA-EPOCH-R protocol, intrathecal methotrexate with each cycle, and GCSF prophylaxis in the Department of Medical Oncology at All India Institute of Medical Sciences, New Delhi, India, from May 1, 2013, to December 2021. Sixteen patients were included in this study. The median age was 35 (21-65) years with a male:female ratio of 3:1. The stage distribution was I/II in 4 cases (25%) and III/IV in 12 cases (75%). Poor performance status (ECOG>2) was observed in 9 cases (56.25%). One case was HIV-positive, and 13 cases (81.2%) were high risk. CSF cytology was negative in all cases at baseline, and 5 cases had bone marrow involvement. Low albumin (serum albumin <3.5 g/dL) was seen in 6/16 cases (37.5%). After the median 5 cycles (range 3-6) of chemotherapy, the overall response was 93.7%, and 81.25% of patients achieved complete response. The maximum dose intensity was level 3 in 6 patients, level 2 in 9 patients, and level 1 in 1 patient. There were no treatment-related deaths. The most common hematological toxicities (grade 3-4) were neutropenia in 3 patients, thrombocytopenia in 1 patient, and anemia in 2 patients. Febrile neutropenia was observed in 2 patients. Infections, thrombosis, and Grade 3 peripheral neuropathy were documented in 4, 2, and 1 cases, respectively. In our study, 2-year event-free survival and overall survival were 75.4% and 83%, respectively, with a median follow-up period of 27 months. DA-EPOCH-R is an effective and safe protocol even in high-risk adult Burkitt lymphoma patients.

Clinical relevance of molecular characteristics in Burkitt lymphoma differs according to age

While survival has improved for Burkitt lymphoma patients, potential differences in outcome between pediatric and adult patients remain unclear. In both age groups, survival remains poor at relapse. Therefore, we conducted a comparative study in a large pediatric cohort, including 191 cases and 97 samples from adults. While TP53 and CCND3 mutation frequencies are not age related, samples from pediatric patients showed a higher frequency of mutations in ID3, DDX3X, ARID1A and SMARCA4, while several genes such as BCL2 and YY1AP1 are almost exclusively mutated in adult patients. An unbiased analysis reveals a transition of the mutational profile between 25 and 40 years of age. Survival analysis in the pediatric cohort confirms that TP53 mutations are significantly associated with higher incidence of relapse (25 ± 4% versus 6 ± 2%, p-value 0.0002). This identifies a promising molecular marker for relapse incidence in pediatric BL which will be used in future clinical trials.

Phosphorylation of PBK/TOPK Tyr74 by JAK2 promotes Burkitt lymphoma tumor growth

Burkitt lymphoma (BL), which is characterized by high invasiveness, is a subgroup of non-Hodgkin lymphoma. Although BL is regarded as a highly curable disease, especially for children, some patients unfortunately still do not respond adequately. The understanding of the etiology and molecular mechanisms of BL is still limited, and targeted therapies are still lacking. Here, we found that T-LAK cell-derived protein kinase (TOPK) and phosphorylated Janus kinase 2 (p-JAK2) are highly expressed in the tissues of BL patients. We report that TOPK directly binds to and is phosphorylated at Tyr74 by JAK2. Histone H3, one of the downstream targets of TOPK, is also phosphorylated in vivo and in vitro. Furthermore, we report that the phosphorylation of TOPK at Tyr74 by JAK2 plays a vital role in the proliferation of BL cells and promotes BL tumorigenesis in vivo. Phosphorylation of TOPK at Tyr74 by JAK2 enhances the stability of TOPK. Collectively, our results suggest that the JAK2/TOPK/histone H3 axis plays a key role in the proliferation of BL cells and BL tumorigenesis in vivo.

L-Asparaginase synergizes with etoposide via the PI3K/Akt/mTOR pathway in Epstein-Barr virus-positive Burkitt lymphoma.

Burkitt lymphoma (BL) is an aggressive Epstein-Barr virus (EBV)-driven B-cell lymphoma characterized by the translocation and rearrangement of the c-Myc proto-oncogene. High-intensity multidrug chemotherapy regimens have a limited effect on the survival of refractory or relapsed BL patients, mainly owing to the high EBV load and drug resistance. l-asparaginase ( l-Asp) and etoposide (VP-16) play a beneficial role in EBV-related lymphoproliferative diseases; however, their roles and mechanisms in BL remain unclear. In this study, we found that VP-16 inhibited BL cell proliferation and arrested the cell cycle at the G2 /M phase. It also induced autophagy and activated the extrinsic and intrinsic apoptotic signaling pathways in BL cells. Mechanistically, VP-16 inhibited c-Myc expression and regulated the PI3K/Akt/mTOR signaling pathway. Notably, VP-16 also showed a specific synergistic effect with l-Asp to induce apoptosis in EBV-positive BL cells but not in EBV-negative BL cells. VP-16 combined with l-Asp further inhibited c-Myc expression and downregulated the PI3K/Akt/mTOR signaling pathway. Additionally, we found that VP-16 inhibited the expression of latent membrane protein 1 (LMP1), and in combination with l-Asp further decreased LMP1 expression in Raji cells. Our in vivo data also showed that the dual-drug combination significantly inhibited the growth of BL tumors and prolonged the survival of mice compared to VP-16 alone. In conclusion, this study provides new evidence that l-Asp may enhance the antitumor effect of VP-16 by inhibiting the PI3K/Akt/mTOR signaling pathway in EBV-positive BL cells.

PB2135: BURKITT LYMPHOMA INTERNATIONAL PROGNOSTIC INDEX (BL-IPI): IS IT EFFICIENT ENOUGH IN ADULT BURKITT LYMPHOMA PATIENTS?

Background: Burkitt lymphoma is a rare but clinically severe subtype of non-Hodgkin lymphoma. An ideal risk scoring system specific to Burkitt lymphoma had not been available for many years, however Burkitt Lymphoma International Prognostic Index (BL-IPI) has been recently proposed by Olszewski et al. BL-IPI is consisted of following risk factors; age ≥ 40 years, performance status ≥ 2, serum lactate dehydrogenase (LDH) ≥ 3X upper limit of normal (ULN), and central nervous system (CNS) involvement. Accordingly, patients are grouped as low risk (zero risk factor) disease, intermediate risk (one risk factor) and high risk (≥2 risk factors). Aims: Our aims were to examine the basic characteristics and survival rates of Burkitt lymphoma patients that are being treated in our institution, to determine the prognostic factors which affect survival and to evaluate the efficacy of BL-IPI and other risk scoring systems in our patient population. Methods: Patients who were 18 years or older and diagnosed with Burkitt lymphoma between 2000-2021 at Hacettepe University Hospital were included in our study. Patient, disease and treatment characteristics were reviewed through hospital electronic health records. Disease free survival (DFS) and overall survival (OS) were determined as the primary endpoints. Variables that have prognostic impact were identified through univariate and multivariate analyses. Finally, the efficacy of BL-IPI was tested in our patient population. Statistical analyses were conducted using SPSS version 25. Results: A total of 71 patients whose median age of diagnosis was 40 (IQR: 29-55) and median follow-up time was 11,4 months (minimum 0,33, maximum 243,67 months) were included in our study. 1 year OS was estimated as 58%, 3 year OS as 53% and 3 year DFS as 64%. Factors affecting survival were examined and in univariate analyses; performance status ≥ 2, stage 4 disease, bone marrow involvement, CNS involvement, serum LDH > ULN, hypoalbuminemia, anemia and thrombocytopenia were associated with lower 3-year OS (p<0,05); while stage 4 disease, bone marrow involvement, anemia and thrombocytopenia were associated with lower 3-year DFS (p<0,05). In multivariate analysis, only performance status ≥ 2, stage 4 disease, bone marrow involvement and thrombocytopenia caused a statististically significant increase in death rate (p<0,05). CNS involvement caused a near significant increase (p=0,067). 25,4% of the patients had low risk, 31% of the patients had intermediate risk and 34,6% of the patients had high risk disease according to BL-IPI. 3-year OS rates were 82%, 65% and 27% respectively, and 3-year PFS rates were 81%, 71% and 36% respectively. Image:Summary/Conclusion: Our study supports the fact that BL-IPI predicts survival efficiently, however taking our aforementioned results into consideration, we propose that instead of “CNS involvement”, “CNS involvement and bone marrow involvement” or “stage 4 disease” could be added to the score as a risk factor. In the study conducted by Olszewski et al., 58% of the patients in the low risk group had advanced stage disease, however only 12% had bone marrow involvement, which is a relatively low ratio compared to literature. Studies involving larger cohorts who have higher bone marrow involvement ratios consistent with the literature are undoubtedly needed to support this proposition.

RNA helicase DHX15 decreases cell apoptosis by NF-\u03baB signaling pathway in Burkitt lymphoma

BackgroundDHX15 is one of the RNA helicase family members involving in several biological processes. Studies have reported that overexpression of DHX15 is related to cancer progression. However, the role of DHX15 in Burkitt lymphoma (BL) and latent Epstein-Barr virus (EBV) infection remains to be elucidated.MethodsExpression of DHX15 was measured in BL patient by immunohistochemical staining. In vitro study, a CCK-8 assay was used to analyze cell proliferation and flow cytometry was performed to assess cell cycle, apoptosis and mitochondria membrane potential. Members of NF-κB signaling pathway and apoptotic-related proteins expression were measured by western-blot. EBV latent infection products and RNA polymerase III transcripts expression were determined by quantitative real-time PCR and western-blot. In vivo study, HE, IHC, TUNEL and ISH assays were used to analyze the effect of DHX15 on subcutaneous tumor nodes formation.ResultsDHX15 was overexpressed in Burkitt lymphoma patients and tends to be associated with poor progression-free survival and poor overall survival. Knockdown of DHX15 significantly inhibited BL tumor growth, reduced cell proliferation, induced cell cycle arrest and increased cell apoptosis. Further analysis showed that canonical NF-κB signaling and its downstream targets, mitochondria and Caspase were involved in the increased cell apoptosis after DHX15 gene knockdown. Furthermore, knockdown of DHX15 reduced EBV latent infection products expression and inhibited RNA polymerase III activity.ConclusionDHX15 may be an oncogene in the development of BL and a potential therapeutic target for the treatment of BL and latent EBV infection.

Burkitt lymphoma – no impact of HIV status on outcomes with rituximab-based chemoimmunotherapy

We analyzed the prognostic factors for treatment outcomes amongst 34 patients with adult Burkitt lymphoma (BL) who received rituximab with standard first-line chemotherapy. Seven patients had human immunodeficiency virus (HIV)-associated BL. Overall, we observed a complete remission (CR) rate of 91.2%, and 10-year progression-free survival (PFS) and overall survival (OS) was 84.8 and 88.2%, respectively. In patients with concomitant HIV, the prognosis was not different with 10-year PFS of 100% and OS of 88.2%. The majority (71.4%) of HIV-associated BL patients received dose-adjusted EPOCH-R (etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab) and had excellent outcomes with 100% CR and no relapses. Central nervous system (CNS) disease, bone marrow involvement and elevated serum lactate dehydrogenase (LDH) levels more than 3 times upper limit of normal (ULN) were associated with poorer survival outcomes. Patients with refractory disease, whilst uncommon (n = 4), had dismal outcomes. Patients with adult BL, including HIV-related cases, harbor generally good prognosis in the modern era.