Molecular Pathogenesis of Diffuse Large B-Cell Lymphoma

An overview of sphingosine-1-phosphate receptor 2: Structure, biological function, and small-molecule modulators

Over the past decade, there has been a notable increase in research on sphingosine-1-phosphate receptor 2 (S1PR2), which is a type of G-protein-coupled receptor. Upon activation by S1P or other ligands, S1PR2 initiates downstream signaling pathways such as phosphoinositide 3-kinase (PI3K), Mitogen-activated protein kinase (MAPK), Rho/Rho-associated coiled-coil containing kinases (ROCK), and others, contributing to the diverse biological functions of S1PR2 and playing a pivotal role in various physiological processes and disease progressions, such as multiple sclerosis, fibrosis, inflammation, and tumors. Due to the extensive biological functions of S1PR2, many S1PR2 modulators, including agonists and antagonists, have been developed and discovered by pharmaceutical companies (e.g., Novartis and Galapagos NV) and academic medicinal chemists for disease diagnosis and treatment. However, few reviews have been published that comprehensively overview the functions and regulators of S1PR2. Herein, we provide an in-depth review of the advances in the function of S1PR2 and its modulators. We first summarize the structure and biological function of S1PR2 and its pathological role in human diseases. We then focus on the discovery approach, design strategy, development process, and biomedical application of S1PR2 modulators. Additionally, we outline the major challenges and future directions in this field. Our comprehensive review will aid in the discovery and development of more effective and clinically applicable S1PR2 modulators.

MYCT1 inhibits hematopoiesis in diffuse large B-cell lymphoma by suppressing RUNX1 transcription

BACKGROUND

The abnormality of chromosomal karyotype is one factor causing poor prognosis of lymphoma. In the analysis of abnormal karyotype of lymphoma patients, three smallest overlap regions were found, in which MYCT1 was located. MYCT1 is the first tumor suppressor gene cloned by our research team, but its studies relating to the occurrence and development of lymphoma have not been reported.

METHODS

R banding analyses were employed to screen the abnormality of chromosomal karyotype in clinical specimen and MYCT1 over-expression cell lines. FISH was to monitor MYCT1 copy number aberration. RT-PCR and Western blot were to detect the mRNA and protein levels of the MYCT1 and RUNX1 genes, respectively. The MYCT1 and RUNX1 protein levels in clinical specimen were evaluated by immunohistochemical DAB staining. The interaction between MYCT1 and MAX proteins was identified via Co-IP and IF. The binding of MAX on the promoter of the RUNX1 gene was detected by ChIP and Dual-luciferase reporter assay, respectively. Flow cytometry and CCK-8 assay were to explore the effects of MYCT1 and RUNX1 on the cell cycle and proliferation, respectively.

RESULTS

MYCT1 was located in one of three smallest overlap regions of diffuse large B-cell lymphoma, it altered chromosomal instability of diffuse large B-cell lymphoma cells. MYCT1 negatively correlated with RUNX1 in lymphoma tissues of the patients. MAX directly promoted the RUNX1 gene transcription by binding to its promoter region. MYCT1 may represses RUNX1 transcription by binding MAX in diffuse large B-cell lymphoma cells. MYCT1 binding to MAX probably suppressed RUNX1 transcription, leading to the inhibition of proliferation and cell cycle of the diffuse large B-cell lymphoma cells.

CONCLUSION

This study finds that there is a MYCT1-MAX-RUNX1 signaling pathway in diffuse large B-cell lymphoma. And the study provides clues and basis for the in-depth studies of MYCT1 in the diagnosis, treatment and prognosis of lymphoma.

Investigating In Situ Expression of c-MYC and Candidate Ubiquitin-Specific Proteases in DLBCL and Assessment for Peptidyl Disruptor Molecule against c-MYC-USP37 Complex

Diffuse Large B-Cell Lymphoma (DLBCL) is the most common form of non-Hodgkin's lymphoma (NHL). Elevated expression of c-MYC in DLBCL is associated with poor prognosis of the disease. In different cancers, c-MYC has been found regulated by different ubiquitin-specific proteases (USPs), but to date, the role of USPs in c-MYC regulation has not been investigated in DLBCL. In this study, in situ co expression of c-MYC and three candidates USPs, USP28, USP36 and USP37, have been investigated in both the ABC and GCB subtypes of DLBCL. This shows that USP37 expression is positively correlated with the c-MYC expression in the ABC subtype of DLBCL. Structurally, both c-MYC and USP37 has shown large proportion of intrinsically disordered regions, minimizing their chances for full structure crystallization. Peptide array and docking simulations has shown that N-terminal region of c-MYC interacts directly with residues within and in proximity of catalytically active C19 domain of the USP37. Given the structural properties of the interaction sites in the c-MYC-USP37 complex, a peptidyl inhibitor has been designed. Molecular docking has shown that the peptide fits well in the targeted site of c-MYC, masking most of its residues involved in the binding with USP37. The findings could further be exploited to develop therapeutic interventions against the ABC subtype of DLBCL.

Viral Agents as Potential Drivers of Diffuse Large B-Cell Lymphoma Tumorigenesis

Among numerous causative agents recognized as oncogenic drivers, 13% of total cancer cases occur as a result of viral infections. The intricacy and diversity of carcinogenic processes, however, raise significant concerns about the mechanistic function of viruses in cancer. All tumor-associated viruses have been shown to encode viral oncogenes with a potential for cell transformation and the development of malignancies, including diffuse large B-cell lymphoma (DLBCL). Given the difficulties in identifying single mechanistic explanations, it is necessary to combine ideas from systems biology and viral evolution to comprehend the processes driving viral cancer. The potential for more efficient and acceptable therapies lies in targeted medicines that aim at viral proteins or trigger immune responses to either avoid infection or eliminate infected or cancerous cells. In this review, we aim to describe the role of viral infections and their mechanistic approaches in DLBCL tumorigenesis. To the best of our knowledge, this is the first review summarizing the oncogenic potential of numerous viral agents in DLBCL development.

Quality of life of survivors 1 year after the diagnosis of diffuse large B-cell lymphoma: a LYSA study

Health-related quality of life (HRQoL) is a multidimensional concept including physical, emotional, social, and cognitive functions, disease symptoms, and side effects of treatment. Differences in HRQoL due to gender, existence of comorbidities, and number of chemotherapy cycles are little explored in diffuse large B-cell lymphoma (DLBCL) survivors. Our objective was to investigate whether differences in HRQoL in function of these factors exist 1 year after the diagnosis of DLBCL. One hundred and one patients, enrolled in the RT3 (Real-Time Tailored Therapy) Study, answered self-administrated European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30), EORTC High-Grade Non-Hodgkin Lymphoma (NHL-HG29), Hospital Anxiety and Depression Scale (HADS), Post Traumatic Growth Inventory (PTGI), and Multidimensional Fatigue Inventory (MFI) questionnaires. Adjusted means of scores were calculated in multivariate linear regression models. Fifty-seven survivors (mean age of 58.5 years) answered all questionnaires. Women have significantly higher scores of posttraumatic growth and lower physical functioning than men (P < 0.04). Survivors with comorbidities have increased physical fatigue and symptom burden, increased emotional impact, mental fatigue and depression, and reduced physical functioning and global health status (all P < 0.05). A greater number of cycles of chemotherapy increase the level of symptoms (pain, neuropathy, and dyspnoea; P < 0.05). The various aspects related to HRQoL should be discussed with DLBCL patients and investigated, with the aim of developing strategies to ensure appropriate psychosocial and supportive care and to improve the HRQoL in these patients.

Advances in chimeric antigen receptor T-cell therapy for B-cell non-Hodgkin lymphoma

B-cell non-Hodgkin lymphoma (B-NHL) is a group of heterogeneous disease which remains incurable despite developments of standard chemotherapy regimens and new therapeutic agents in decades. Some individuals could have promising response to standard therapy while others are unresponsive to standard chemotherapy or relapse after autologous hematopoietic stem-cell transplantation (ASCT), which indicates the necessity to develop novel therapies for refractory or relapsed B-NHLs. In recent years, a novel cell therapy, chimeric antigen receptor T-cell therapy (CAR-T), was invented to overcome the limitation of traditional treatments. Patients with aggressive B-NHL are considered for CAR-T cell therapy when they have progressive lymphoma after second-line chemotherapy, relapse after ASCT, or require a third-line therapy. Clinical trials of anti-CD19 CAR-T cell therapy have manifested encouraging efficacy in refractory or relapsed B-NHL. However, adverse effects of this cellular therapy including cytokine release syndrome, neurotoxicity, tumor lysis syndrome and on-target, off-tumor toxicities should attract our enough attention despite the great anti-tumor effects of CAR-T cell therapy. Although CAR-T cell therapy has shown remarkable results in patients with B-NHL, the outcomes of patients with B-NHL were inferior to patients with acute lymphoblastic leukemia. The inferior response rate may be associated with physical barrier of lymphoma, tumor microenvironment and low quality of CAR-T cells manufactured from B-NHL patients. Besides, some patients relapsed after anti-CD19 CAR-T cell therapy, which possibly were due to limited CAR-T cells persistence, CD19 antigen escape or antigen down-regulation. Quite a few new antigen-targeted CAR-T products and new-generation CAR-T, for example, CD20-targeted CAR-T, CD79b-targeted CAR-T, CD37-targeted CAR-T, multi-antigen-targeted CAR-T, armored CAR-T and four-generation CAR-T are developing rapidly to figure out these deficiencies.

Value of total lesion glycolysis and cell-of-origin subtypes for prognostic stratification of diffuse large B-cell lymphoma patients

Background

This study aimed to explore the added prognostic value of baseline metabolic volumetric parameters and cell of origin subtypes to the National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) in nodal diffuse large B-cell lymphoma (DLBCL) patients.

Methods

A total of 184 consecutive de novo nodal DLBCL patients who underwent baseline positron emission tomography/computed tomography (PET/CT) were included in this study. Kaplan-Meier estimates were generated to evaluate the clinical, biological, and PET/CT parameters' prognostic value. The Cox proportional hazards model was performed to examine the potential independent predictors for progression-free survival (PFS) and overall survival (OS).

Results

With a median follow-up of 35 months, the 3-year PFS and OS were 65.2% and 73.0%, respectively. In univariate analysis, total lesion glycolysis (TLG), cell-of-origin subtypes, and NCCN-IPI were both PFS and OS predictors. High TLG (≥1,852), non-germinal center B (non-GCB), as well as high NCCN-IPI (≥4), were shown to be independently significantly associated with inferior PFS and OS after multivariate analysis. Based on the number of risk factors (high TLG, non-GCB, and high NCCN-IPI), a revised risk model was designed, and the participants were divided into four risk groups with very different outcomes, in which the PFS rates were 89.7%, 66.2%, 51.7%, and 26.7% (χ²=30.179, P<0.001), and OS rates were 93.1%, 73.8%, 56.7%, and 43.3%, respectively (χ²=23.649, P<0.001), respectively. Compared with the NCCN-IPI alone, the revised risk model showed a stronger ability to reveal further discrimination among subgroups, especially for participants with very unfavorable survival outcomes (PFS: χ²=9.963, P=0.002; OS: χ²=4.166, P=0.041, respectively).

Conclusions

The TLG, cell-of-origin subtypes, and NCCN-IPI are independent prognostic survival factors in DLBCL patients. Moreover, the revised risk model composed of the number of risk factors (high TLG, non-GCB, and high NCCN-IPI) can stratify patients better than the NCCN-IPI, especially for patients at high risk, which suggests its potential integration into decision making for personalized medicine.

Genetic Events Inhibiting Apoptosis in Diffuse Large B Cell Lymphoma

Simple Summary

Diffuse large B cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma (NHL). Despite the genetic heterogeneity of the disease, most patients are initially treated with a combination of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP), but relapse occurs in ~50% of patients. One of the hallmarks of DLBCL is the occurrence of genetic events that inhibit apoptosis, which contributes to disease development and resistance to therapy. These events can affect the intrinsic or extrinsic apoptotic pathways, or their modulators. Understanding the factors that contribute to inhibition of apoptosis in DLBCL is crucial in order to be able to develop targeted therapies and improve outcomes, particularly in relapsed and refractory DLBCL (rrDLBCL). This review provides a description of the genetic events inhibiting apoptosis in DLBCL, their contribution to lymphomagenesis and chemoresistance, and their implication for the future of DLBCL therapy.

Abstract

Diffuse large B cell lymphoma (DLBCL) is curable with chemoimmunotherapy in ~65% of patients. One of the hallmarks of the pathogenesis and resistance to therapy in DLBCL is inhibition of apoptosis, which allows malignant cells to survive and acquire further alterations. Inhibition of apoptosis can be the result of genetic events inhibiting the intrinsic or extrinsic apoptotic pathways, as well as their modulators, such as the inhibitor of apoptosis proteins, P53, and components of the NF-kB pathway. Mechanisms of dysregulation include upregulation of anti-apoptotic proteins and downregulation of pro-apoptotic proteins via point mutations, amplifications, deletions, translocations, and influences of other proteins. Understanding the factors contributing to resistance to apoptosis in DLBCL is crucial in order to be able to develop targeted therapies that could improve outcomes by restoring apoptosis in malignant cells. This review describes the genetic events inhibiting apoptosis in DLBCL, provides a perspective of their interactions in lymphomagenesis, and discusses their implication for the future of DLBCL therapy.

Quantitative analysis of tumor-specific BCL2 expression in DLBCL: refinement of prognostic relevance of BCL2

BCL2 overexpression has been reported to be associated with poor prognosis in patients with diffuse large B-cell lymphoma (DLBCL). However, currently there is no consensus on the evaluation of BCL2 expression and only the proportion of BCL2 positive cells are evaluated for the determination of BCL2 positivity. This study aimed to define BCL2 positivity by quantitative analysis integrating both the intensity and proportion of BCL2 expression. BCL2 expression of 332 patients (221 patients for the training set and 111 patients for the validation set) with newly diagnosed DLBCL who received R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) were analyzed using the tumor-specific automated quantitative analysis (AQUA) scoring method based on multiplex immunofluorescence. In the training set, high BCL2 AQUA score (N = 86, 38.9%) was significantly associated with poor prognosis (p = 0.01, HR 2.00; 95% CI [1.15–3.49]) independent of international prognostic index, cell of origin, and MYC expression. The poor prognostic impact of the high BCL2 AQUA score was validated in the validation set. AQUA scoring of BCL2 expression incorporating both the intensity and proportion of BCL2 positive cells was independently associated with survival outcomes of patients with primary DLBCL treated with R-CHOP.

FOXM1-induced upregulation of lncRNA OR3A4 promotes the progression of diffuse large B-cell lymphoma via Wnt/β-catenin signaling pathway

Diffuse large B-cell lymphoma (DLBCL) is a leading cause of non-Hodgkin lymphomas. Existing researches have verified that long non-coding RNAs (lncRNAs) play crucial roles in the development of DLBCL, nevertheless, whether lncRNA OR3A4 has influences on the progression of DCBCL needs further exploration. In our study, it was revealed that the expression of OR3A4 was upregulated in DLBCL tumors and cell lines, and patients with high OR3A4 expression suffered from poor prognosis. Knockdown of OR3A4 suppressed cell proliferation and promoted cell apoptosis in DLBCL. Moreover, knockdown of OR3A4 inactivated Wnt/β-catenin signaling pathway, and Riluzole treatment could partially rescue the inhibitive effect of OR3A4 silencing on DLBCL cell proliferation. Furthermore, FOXM1 expression was discovered to be upregulated in DLBCL tissues, and it positively modulated the expression of OR3A4 at transcriptional leve. It was also revealed that FOXM1 knockdown inactivated Wnt/β-catenin signaling pathway. Finally, rescue assays confirmed that OR3A4 overexpression or the treatment of Riluzole could partially countervail the inhibitive effect of FOXM1 silencing on DLBCL progression. Taken together, FOXM1-induced upregulation of OR3A4 enhances the occurrence of DLBCL via Wnt/β-catenin signaling pathway.

The critical role of RasGRP4 in the growth of diffuse large B cell lymphoma

Background

This study aimed to confirm that blocking RasGRP4 can effectively slow down the growth of DLBCL both in vitro and in vivo and ascertain the role of RasGRP4 in the prognosis of DLBCL clinically.

Methods

RasGRP4 expression levels were examined in benign tissues and lymphomas. In order to verify somatic mutation in RasGRP4 gene, cDNA sequencing was performed in DLBCL patients. RasGRP4-dependent cell proliferation, mitochondrial membrane potential, oxidative stress levels and signaling pathway changes were measured by knockdown of RasGRP4. Tumor growth was monitored in xenografted lymphoma model. Clinical data were collected to confirm the role of RasGRP4 in DLBCL.

Results

RasGRP4 expression was significantly elevated in DLBCL while no somatic mutations were detected of this gene in DLBCL patients. Decreased RasGRP4 significantly inhibited cell proliferation by simultaneously reducing mitosis and promoting apoptosis and increased the oxidative stress levels. Mechanistically, reduced expression of RasGRP4 decreased ERK while increased JNK expression in SUDHL-4 cells. Knockdown of RasGRP4 also significantly inhibited tumor formation in vivo. Furthermore, RasGRP4 expression levels were significantly higher in patients with larger DLBCL lesions (P = 0.0004), high-risk international prognostic index score groups (P = 0.0042), and its expression was positively correlated with maximum standardized uptake value in DLBCL (P = 0.0004).

Conclusions

These findings indicate the oncogenic role of RasGRP4 in DLBCL, suggesting it as a prognostic biomarker and potential therapeutic target in DLBCL.

Electronic supplementary material

The online version of this article (10.1186/s12964-019-0415-6) contains supplementary material, which is available to authorized users.

Diffuse large B-cell lymphoma recurrence presenting as multiple, progressive cranial neuropathies

A 58-year-old man with a history of rheumatoid arthritis and stage IV diffuse large B-cell lymphoma, in complete remission with no evidence of residual disease on positron emission tomography/CT after completing six cycles of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone chemotherapy, presented with acute onset of dysphagia to solids and liquids. On further evaluation, his dysphagia was attributed to a vagus nerve palsy, and later during his admission, he developed rapidly progressing left facial and vestibulocochlear nerve palsies. Imaging studies displayed pathological enhancement of bilateral seventh and eighth cranial nerves, concerning for leptomeningeal recurrence of lymphoma. Cerebrospinal fluid analysis and flow cytometry were confirmatory, revealing markedly atypical monotypic CD19 positive B cells.

Efficacy of salvage chemotherapy in diffuse large B cell lymphoma with primary treatment failure according to putative cell of origin

We evaluated outcome of 235 primary treatment failure (PTF) diffuse large B-cell lymphoma (DLBCL) patients based on salvage chemotherapy regimen and putative cell-of-origin (COO). Patients were divided into two groups; group A (n = 38) received high-dose cytarabine containing regimen, either DHAP or ESHAP. Patients in group B (n = 197) received ifosfamide, carboplatin, and etoposide (ICE) +/- rituximab. No difference in overall response rates (CR + PR) was observed based on salvage chemotherapy regimen and COO. After adjustment for the presence of ultra high-risk features, overall survival of germinal center B-cell like (GCB) DLBCL patients in group A was not significantly different from survival in group B (HR 0.86, 95% CI 0.46-1.60, p = .64). Similarly, within non-GCB DLBCL cohort, survival in group A was comparable to group B (HR 0.53, 95% CI 0.20-1.44, p = .21). We did not find an outcome difference between two commonly used salvage chemotherapy regimens in patients with PTF DLBCL based on COO.

B-cell receptor-mediated NFATc1 activation induces IL-10/STAT3/PD-L1 signaling in diffuse large B-cell lymphoma

Knowledge of programmed death ligand 1 (PD-L1) expression and its regulation in B-cell lymphoma cells is limited. Investigating mechanisms that control PD-L1 expression in B-cell lymphoma cells might identify biomarkers that predict the efficacy of immunotherapy with anti-programmed death-1/PD-L1 antibodies. In addition, identification of mechanisms that regulate PD-L1 may identify molecules that can be targeted to improve the clinical efficacy of immune checkpoint inhibitors. In this study, we used proteomic approaches and patient-derived B-cell lymphoma cell lines to investigate mechanisms that regulate PD-L1 expression. We found that PD-L1 expression, particularly in nongerminal center B cell-derived diffuse large B-cell lymphoma (DLBCL), is controlled and regulated by several interactive signaling pathways, including the B-cell receptor (BCR) and JAK2/STAT3 signaling pathways. We found that that BCR-mediated NFATc1 activation upregulates IL-10 chemokine expression in PD-L1⁺ B-cell lymphoma cells. Released IL-10 activates the JAK2/STAT3 pathway, leading to STAT3-induced PD-L1 expression. IL-10 antagonist antibody abrogates IL-10/STAT3 signaling and PD-L1 protein expression. We also found that BCR pathway inhibition by BTK inhibitors (ibrutinib, acalabrutinib, and BGB-3111) blocks NFATc1 and STAT3 activation, thereby inhibiting IL-10 and PD-L1 expression. Finally, we validated the PD-L1 signaling network in 2 primary DLBCL cohorts consisting of 428 and 350 cases and showed significant correlations among IL-10, STAT3, and PD-L1. Thus, our findings reveal a complex signaling network regulating PD-L1 expression in B-cell lymphoma cells and suggest that PD-L1 expression can be modulated by small molecule inhibitors to potentiate immunotherapies.

The Role of Macrophage/B-Cell Interactions in the Pathophysiology of B-Cell Lymphomas

Macrophages (MPs) are heterogeneous, multifunctional, myeloid-derived leukocytes that are part of the innate immune system, playing wide-ranging critical roles in basic biological activities, including maintenance of tissue homeostasis involving clearance of microbial pathogens. Tumor-associated MPs (TAMs) are MPs with defined specific M2 phenotypes now known to play central roles in the pathophysiology of a wide spectrum of malignant neoplasms. Also, TAMs are often intrinsic cellular components of the essential tumor microenvironment (TME). In concert with lymphoid-lineage B and T cells at various developmental stages, TAMs can mediate enhanced tumor progression, often leading to poor clinical prognosis, at least partly through secretion of chemokines, cytokines, and various active proteases shown to stimulate tumor growth, angiogenesis, metastasis, and immunosuppression. Researchers recently showed that TAMs express certain key checkpoint-associated proteins [e.g., programmed cell death protein 1 (PD-1), programmed cell death-ligand 1 (PD-L1)] that appear to be involved in T-cell activation and that these proteins are targets of other specific checkpoint-blocking immunotherapies (anti-PD-1/PD-L1) currently part of new therapeutic paradigms for chemotherapy-resistant neoplasms. Although much is known about the wide spectrum and flexibility of MPs under many normal and neoplastic conditions, relatively little is known about the increasingly important interactions between MPs and B-lymphoid cells, particularly in the TME in patients with aggressive B-cell non-Hodgkin lymphoma (NHL-B). Normal and neoplastic lymphoid and myeloid cell/MP lineages appear to share many primitive cellular characteristics as well as transcriptional factor interactions in human and animal ontogenic studies. Such cells are capable of ectopic transcription factor-induced lineage reprogramming or transdifferentiation from early myeloid/monocytic lineages to later induce B-cell lymphomagenesis in experimental in vivo murine systems. Close cellular interactions between endogenous clonal neoplastic B cells and related aberrant myeloid precursor cells/MPs appear to be important interactive components of aggressive NHL-B that we discuss herein in the larger context of the putative role of B-cell/MP cellular lineage interactions involved in NHL-B pathophysiology during ensuing lymphoma development.

Prognostic value of pretreatment plasma D-dimer levels in patients with diffuse large B cell lymphoma (DLBCL)

BACKGROUND

We assessed the prognostic significance of D-dimer in patients of diffuse large B cell lymphoma (DLBCL).

METHODS

We performed a retrospective study including 254 patients who were newly diagnosed DLBCL. X-tile was used to generate a cutoff value for D-dimer. Both univariate screen by Cox proportional hazard model and multivariable analysis by Cox regression model were used to assess the impact of pretreatment D-dimer levels on the overall survival (OS).

RESULT

According to X-tile, the optimal cut-off value of D-dimer for prediction of survival was set as 1.6 μg/mL, and a D-dimer level ≥ 1.6 μg/mL was significantly associated with poor overall survival (OS) (OS: 31.7 vs. 79.1%, P < 0.001). In multivariable analysis, it was found that a higher D-dimer level was an independent predictor for worse OS (Hazard ratio (HR): 3.594 95% Confidence interval (CI): 2.296-5.267, P < 0.001). In subgroup analysis of International Prognostic Index (IPI), survival of low-risk and intermediate-risk group with a D-dimer level ≥ 1.6 μg/mL were both similar to that of the high-risk group (OS: 31.6 vs. 36.5%, P = 0.957; OS: 38.0 vs. 36.5%, P = 0.758). In addition, among patients treated with surgery, those with higher D-dimer had substantially worse survival than that with lower D-dimer (OS: 27.0 vs. 84.5%, P < 0.001).

CONCLUSION

Pretreatment D-dimer is a simple but effective predictor of survival among patients with DLBCL.

Giant solitary primary intracranial lymphoma masquerading as meningioma: a case and review of literature

Non-Hodgkin's lymphomas (NHL) with intracranial origin are very rare and constitutes about 1-2% of primary central nervous system lymphomas (PCNSL). Diffuse large B cell lymphoma (DLBCL) is the most common subtype of NHL and mostly seen in immunocompromised patients. Therefore, the occurrence of giant solitary DLBCL in an immunocompetent patient is puzzling. We present a case of 68-year-old man who was admitted at our facility with a history of “hypomnesia of two (2) months” duration. Magnetic resonance imaging (MRI) revealed a space occupying lesion in the bilateral frontal lobe and corpus callosum measuring about 5.4cm * 4.6cm * 3.8cm with mixed signal intensities and vasogenic edema around the mass. Radiological, this mass was mistaken for meningioma until histopathological studies revealed DLBCL. Giant solitary primary intracranial lymphomas are very rare and can be mistake for meningioma even with very experience radiologist or neurosurgeon since the radiological features of PCNSL can be very unspecific. We achieved to total resection because of the giant and solitary nature of our case. The prognosis of PCNSL is general very poor when the patient is immunocompromised. In immunocompetent patients, who are well managed with surgery and chemotherapy, the overall survival and quality of life can very encouraging.

Prognostic value of expression of nuclear factor kappa-B/p65 in non-GCB DLBCL patients

Purpose

We estimated the expression of nuclear factor kappa B/p65 in non-germinal center B-cell-like subtype diffuse large B-cell lymphoma, to investigate its relationship to clinicopathological features, and to further evaluate its prognostic value and clarify its impact on survival.

Results

Among the 49 patients enrolled in this study, 14 (28.6%) had positive p65 expression. The negative p65 group had significantly better survival compared to the positive p65 group in terms of both the 3-year estimated OS (91.2% vs. 39.3%, p = 0.003) and PFS (75.6% vs. 26.5%, p = 0.002). In patients with 4 or more risk factors, p65 was an independent prognostic factor of OS (HR 5.99, 95%CI=1.39-25.75, p=0.016) and PFS (HR 4.01, 95%CI=1.15-14.00, p=0.029).

Materials and Methods

The expression of the NF-κB/p65 protein was deteremined by immunohistochemistry in 49 non-GCB DLBCL. Survival was assessed by the Kaplan–Meier method and Cox multivariate analysis. The median patient follow-up period was 24 months.

Conclusions

The expression of NF-κB/p65 has prognostic value in high risk non-GCB DLBCL, and it is a suitable target for the development of new therapies.

Prognostic Significance of in situ Phenotypic Marker Expression in Diffuse Large B-cell Lymphomas

Diffuse large B-cell lymphomas (DLBCL) are the most common lymphoid malignancies, and encompass all malignant lymphomas characterized by large neoplastic cells and B-cell derivation. In the last decade, DLBCL has been subjected to intense clinical, phenotypic and molecular studies, and were found to represent a heterogeneous group of tumors. These studies suggested new disease subtypes and variants with distinct clinical characteristics, morphologies, immunophenotypes, genotypes or gene expression profiles, associated with distinct prognoses or unique sensitivities to particular therapy regimens. Unfortunately, the reliability and reproducibility of the molecular results remains unclear due to contradictory reports in the literature resulting from small sample sizes, referral and selection biases, and variable methodologies and cut-off levels used to determine positivity. Here, we review phenotypic studies on the prognostic significance of protein expression profiles in DLBCL and reconsider our own retrospective data on 301 primary DLBCL cases obtained on a previously validated tissue microarray in light of powerful statistical methods of determining optimal cut-off values of phenotypic factors for prediction of outcome.

The tumor suppressive role of inhibin βA in diffuse large B-cell lymphoma

INHBA (inhibin βA), a subunit of a ligand of the transforming growth factor-β superfamily, is known to play diverse roles in various solid tumors. However, its role in hematologic malignancies remains unexplored. Here, we investigated the function of INHBA in diffuse large B-cell lymphoma (DLBCL). Both mRNA and protein levels of INHBA were significantly downregulated in primary DLBCL tissues, irrespective of germinal center B-cell-like (GCB) or non-GCB subtype, compared to those in benign tonsils. The low level of INHBA in patients with de novo DLBCL was correlated with reduced overall and progression-free survival. Ectopic expression of INHBA in DLBCL cell lines (OCI-Ly01 and SUDHL-10) resulted in reduced cell proliferation, increased spontaneous apoptosis and arrested cell cycle in vitro and suppressed xenograft tumor growth in vivo. Moreover, INHBA enhanced the chemosensitivity of DLBCL cells. Thus, our results provide novel evidence that INHBA functions as a tumor suppressor in DLBCL.

Prognostic analysis of DLBCL patients and the role of upfront ASCT in high-intermediate and high-risk patients

The role of autologous stem cell transplantation (ASCT) as a frontline treatment in patients with diffuse large B cell lymphoma (DLBCL) who are in their first remission has not been fully elucidated in the rituximab era. We analyzed 272 DLBCL patients who received 4-6 cycles of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) or R-CHOP followed by ASCT, from January 2005 to June 2013 in our institution. Multivariate analysis showed the none germinal center B cell (non-GCB) subtype (P=0.014, P=0.012) and International Prognostic Index (IPI) (3-5) (P=0.004, P=0.016) were independent unfavorable predictors of overall survival (OS) and progression-free survival (PFS), respectively. To investigate the treatment effect of upfront ASCT, we selected 94 high-intermediate and high-risk DLBCL patients who achieved complete remission after R-CHOP, with 41 in the ASCT and 53 in the non-ASCT groups. Survival analysis revealed patients who received upfront ASCT compared with those who did not had better OS (3-year OS: 74.5% vs. 50.4%, P=0.029) or PFS (3-year PFS: 59.6% vs. 32.1%, P=0.004), suggesting up-front ASCT following R-CHOP could improve the outcome of high-intermediate and high-risk DLBCL patients.

CD109, a negative regulator of TGF-β signaling, is a putative risk marker in diffuse large B-cell lymphoma

CD109 is a glycosylphosphatidylinositol-anchored glycoprotein that negatively regulates TGF-β signaling. CD109 was originally identified in hematopoietic tumors; however, the significance of CD109 in hematopoietic malignancies remains unclear. Here, we study the association of CD109 with diffuse large B-cell lymphoma (DLBCL) prognosis. Eighty-four DLBCL specimens were immunohistochemically analyzed for CD109 expression, and 31 and 53 cases were classified into low- and high-CD109 expression groups, respectively. CD109 expression was not associated with overall survival using the Kaplan-Meier analysis and log-rank tests (P = 0.17); however, a significant association was observed between high-CD109 expression and low-1-year survival (P = 0.01). Moreover, in combination with the revised International Prognostic Index (R-IPI), R-IPI-poor/CD109-high was associated with poorer prognosis compared with R-IPI-poor alone. We assessed TGF-β signaling in CD109-depleted Nalm6 cells (a human B-lymphoblastic leukemia/lymphoma cell line), and found prolonged Smad2 phosphorylation compared with control cells after TGF-β1 stimulation, suggesting that CD109 attenuates TGF-β1 signaling in human B-cell tumors. These results suggest that CD109 is a putative biomarker for identifying a high-risk group among DLBCL patients.

Suppression of CD300A inhibits the growth of diffuse large B-cell lymphoma

CD300A is a type I transmembrane receptor protein which has shown inhibitory effects on B-cell receptor-mediated signals. In an analysis of public dataset, we found that CD300A mRNA levels were inversely correlated with the overall survival time of patients with diffuse large B-cell lymphoma (DLBCL). To decipher the role of CD300A in DLBCL, we knocked down the expression levels of CD300A in DLBCL cells and found that decreasing levels of CD300A significantly inhibited cell proliferation of OCI-Ly01, Farage, and SUDHL-4 cells, but not of VAL, OCI-Ly10, or SUDHL-8 cells. Mechanistically, reduced expression of CD300A resulted in a marked attenuation of AKT phosphorylation, a key molecular event in tumorigenesis, in OCI-Ly01, Farage, and SUDHL-4 cells. Pharmacologic inhibition of PI3K displayed a similar inhibitory effect on cell proliferation. Furthermore, using a xenograft animal model, we found that decreasing levels of CD300A in OCI-Ly01 and Farage cells significantly inhibited tumor formation in vivo. Collectively, our results suggested an oncogenic role of CD300A in DLBCL which could serve as a potential biomarker and therapeutic target for this malignant disease.

Pathophysiological significance and therapeutic targeting of germinal center kinase in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma, yet 40% to 50% of patients will eventually succumb to their disease, demonstrating a pressing need for novel therapeutic options. Gene expression profiling has identified messenger RNAs that lead to transformation, but critical events transforming cells are normally executed by kinases. Therefore, we hypothesized that previously unrecognized kinases may contribute to DLBCL pathogenesis. We performed the first comprehensive analysis of global kinase activity in DLBCL, to identify novel therapeutic targets, and discovered that germinal center kinase (GCK) was extensively activated. GCK RNA interference and small molecule inhibition induced cell-cycle arrest and apoptosis in DLBCL cell lines and primary tumors in vitro and decreased the tumor growth rate in vivo, resulting in a significantly extended lifespan of mice bearing DLBCL xenografts. GCK expression was also linked to adverse clinical outcome in a cohort of 151 primary DLBCL patients. These studies demonstrate, for the first time, that GCK is a molecular therapeutic target in DLBCL tumors and that inhibiting GCK may significantly extend DLBCL patient survival. Because the majority of DLBCL tumors (∼80%) exhibit activation of GCK, this therapy may be applicable to most patients.

Long noncoding RNA LUNAR1 associates with cell proliferation and predicts a poor prognosis in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous group of B-cell lymphomas. Exploring a novel and important biomarker is indispensable for understanding the mechanism and clinical course of DLBCL. Emerging studies have shown that aberrant expression of long noncoding RNA (lncRNAs) is strongly associated with carcinogenesis. The aim of this study was to investigate the value of lncRNA LUNAR1 in DLBCL. Quantitative real-time PCR was performed to illustrate the patterns of LUNAR1 expression in tumor tissues and cell lines. The higher expression of LUNAR1 was significantly correlated with stage, rituximab and IPI. Univariate and multivariate analyses showed that LUNAR1 expression served as an independent predictor for overall survival and progression-free survival. Receiver operating characteristic (ROC) curve was constructed to evaluate the diagnostic values and the area under the ROC curve of LUNAR1 was up to 0.9420. Further experiments revealed that LUNAR1 knockdown significantly repressed cell proliferation of DLBCL by regulating E2F1, cyclin D1 and p21. In conclusion, our results indicate that LUNAR1 may serve as a candidate prognostic biomarker through growth regulation in DLBCL.

Impact of Single or Combined Genomic Alterations of TP53, MYC, and BCL2 on Survival of Patients With Diffuse Large B-Cell Lymphomas: A Retrospective Cohort Study

MYC and BCL2 translocations as well as TP53 deletion/mutation are known risk factors in diffuse large B-cell lymphoma (DLBCL) but their interplay is not well understood.In this retrospective cohort study, we evaluated the combined prognostic impact of TP53 deletion and mutation status, MYC and BCL2 genomic breaks in tumor samples of 101 DLBCL patients. The cohort included 53 cases with MYC rearrangements (MYC+).TP53 deletions/mutations (TP53+) were found in 32 of 101 lymphomas and were equally distributed between MYC+ and MYC- cases (35.8% vs. 27.1%). TP53+ lymphomas had lower responses to treatment than TP53- (complete remission 34.4% vs. 60.9%; P = 0.01). TP53 alteration was the dominant independent prognostic factor in multivariate analysis (P = 0.01). Overall survival (OS) varied considerably between subgroups with different genomic alterations: Patients with sole MYC translocation, and interestingly, with triple MYC+/BCL2+/TP53+ aberration had favorable outcomes (median OS not reached) similar to patients without genomic alterations (median OS 65 months). In contrast, patients with MYC+/BCL2+/TP53- double-hit lymphomas (DHL) (28 months), MYC+/BCL2-/TP53+ lymphomas (10 months) or sole TP53 mutation/deletion (12 months) had a poor median OS. Our findings demonstrate differences in OS of DLBCL patients depending on absence or presence of single or combined genetic alterations of MYC, BCL2, and TP53. Cooccurrence of TP53 and BCL2 aberrations ameliorated the poor prognostic impact of single TP53+ or BCL2+ in MYC positive patients.This pilot study generates evidence for the complex interplay between the alterations of genetic pathways in DLBCL, which goes beyond the concept of DHL. The variable survival of DLBCL patients dependent on single or combined alterations in the TP53, MYC, and BCL2 genes indicates the need for comprehensive genomic diagnosis.

Establishment and characterization of a novel MYC/BCL2 "double-hit" diffuse large B cell lymphoma cell line, RC

BACKGROUND

Diffuse large B cell lymphoma (DLBCL) is the most common type of lymphoid malignancy worldwide. Approximately 5 % of cases of DLBCL are so-called double-hit lymphomas (DHL), defined by a chromosomal translocation or rearrangement involving MYC/8q24.2 in combination with another recurrent breakpoint, usually BCL2/18q21.3. Patients with MYC/BCL2 DHL are resistant to standard front-line therapy, and currently, there is no consensus for a therapeutic strategy to treat these patients. Lack of clinically relevant or validated human experimental DHL models of any type that would improve our understanding of the biologic basis of MYC/BCL2 DHL pathophysiology continues to hamper identification of valid therapeutic targets. We describe a unique MYC/BCL2 DHL cell line with morphologic features of DLBCL that we have established, designated as RC.

METHODS

We used tissue culture techniques to establish the RC cell line from primary DLBCL cells. We also utilized molecular and cellular biological techniques including flow cytometry, polymerase chain reaction (PCR), DNA fingerprinting, reverse-phase protein array, conventional cytogenetics, and fluorescence in situ hybridization (FISH) analysis to characterize the RC cell line. NSG-severe combined immunodeficiency (SCID) mice were utilized as a model for xeno-transplantation of RC cells.

RESULTS

RC cells had the following immunophenotype: positive for CD10, CD19, CD20, CD22, CD38, CD43, CD44, and CD79b and negative for CD3, CD4, CD5, CD8, CD11c, CD14, CD30, CD56, and CD200, which was identical to the primary tumor cells. Conventional cytogenetic analysis showed a t(2;8)(p12;q24.2) and t(14;18)(q32;q21.3), corresponding to MYC and BCL2 gene rearrangements, respectively. DNA fingerprinting authenticated the RC cell line to be of the same clone as the primary tumor cells. In addition, RC cells were established in SCID mice as an in vivo model for translational therapeutics studies. Proteomic analysis showed activation of the mTOR signaling pathway in RC cells that can be targeted with an mTOR inhibitor.

CONCLUSION

The data presented confirm the validity of the RC cell line as a representative model of MYC/BCL2 DHL that will be useful for both in vitro and in vivo studies of DHL pathogenesis and therapeutics.

Frontline rituximab, cyclophosphamide, doxorubicin, and prednisone with bortezomib (VR-CAP) or vincristine (R-CHOP) for non-GCB DLBCL

This phase 2 study evaluated whether substituting bortezomib for vincristine in frontline rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy could improve efficacy in non-germinal center B-cell-like diffuse large B-cell lymphoma (non-GCB DLBCL), centrally confirmed by immunohistochemistry (Hans method). In total, 164 patients were randomized 1:1 to receive six 21-day cycles of rituximab 375 mg/m(2), cyclophosphamide 750 mg/m(2), and doxorubicin 50 mg/m(2), all IV day 1, prednisone 100 mg/m(2) orally days 1-5, plus either bortezomib 1.3 mg/m(2) IV days 1, 4, 8, 11 (rituximab, cyclophosphamide, doxorubicin, and prednisone with bortezomib [VR-CAP]; n = 84) or vincristine 1.4 mg/m(2) (maximum 2 mg) IV day 1 (R-CHOP; n = 80). There were no significant differences between VR-CAP and R-CHOP in complete response rate (64.5%, 66.2%; odds ratio [OR], 0.91; P = .80), overall response rate (93.4%, 98.6%; OR, 0.21; P = .11), progression-free survival (hazard ratio [HR], 1.12; P = .76), or overall survival (HR, 0.89; P = .75). Rates of grade ≥3 adverse events (AEs; 88%, 89%), serious AEs (38%, 34%), discontinuations due to AEs (7%, 3%), and deaths due to AEs (2%, 5%) were similar with VR-CAP and R-CHOP. Grade ≥3 peripheral neuropathy rates were 6% and 3%, respectively. VR-CAP did not improve efficacy vs R-CHOP in non-GCB DLBCL. This trial was registered at www.clinicaltrials.gov as #NCT01040871.

Prognostic impact of concordant and discordant bone marrow involvement and cell-of-origin in Korean patients with diffuse large B-cell lymphoma treated with R-CHOP

AIMS

Previous studies have suggested many prognostic factors in diffuse large B-cell lymphoma (DLBCL), but the prognostic importance of cell-of-origin and discordant bone marrow involvement remains unclear. The aim of this study was to evaluate the prognostic impact of bone marrow involvement histological subtype, cell-of-origin subtype and international prognostic index (IPI) scores in patients with DLBCL.

METHODS

Patients who were newly diagnosed with DLBCL and treated with rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) were analysed. Clinical information was reviewed retrospectively. Patients were classified into negative, concordant and discordant bone marrow involvement by histological review. The cell-of-origin types were defined using immunohistochemical analysis.

RESULTS

Both concordant and discordant bone marrow involvement had a negative prognostic impact on progression-free survival, independent of the standard and National Comprehensive Cancer Network (NCCN) IPI scores and cell-of-origin. Patients with non-germinal centre B-cell type showed significantly shorter progression-free survival than those with germinal centre B-cell type. However, non-germinal centre B-cell type did not have a prognostic impact on progression-free survival or overall survival after controlling for the standard and NCCN-IPI and bone marrow involvement.

CONCLUSIONS

Both concordant and discordant bone marrow involvement had an adverse prognostic impact on progression-free survival and overall survival; this was independent of the standard and NCCN-IPI and cell-of-origin (non-germinal centre B-cell type). The NCCN-IPI had more powerful prognostic value than the standard IPI (sIPI). The non-germinal centre B-cell type lost significant prognostic impact on progression-free survival after adjustment for standard and NCCN-IPI and bone marrow involvement.

Evaluation of clinical and biological prognostic factors in relapsed or refractory diffuse large B-cell lymphoma patients after previous treatment with rituximab and chemotherapy: results of the PRO-R-IPI study

INTRODUCTION

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous entity, showing a highly variable outcome. In patients with DLBCL relapsed/refractory to first-line treatment with rituximab the usefulness of the revised International Prognostic Index (R-IPI) as a prognostic tool remains unexplored. Some biological parameters (B-cell lymphoma 6 [Bcl-6], Bcl-2, p53, and multiple myeloma 1 [MUM1]) and blood populations (lymphocyte and monocyte counts) have been described as International Prognostic Index-independent prognostic factors. The objective was to evaluate the R-IPI to predict the outcome of DLBCL patients at the time of relapse after a front-line treatment with chemotherapy and rituximab and to establish in this population the relationship between biological parameters and outcome.

PATIENTS AND METHODS

We included patients with refractory/relapsed DLBCL after first-line treatment with rituximab-containing regimens; patients must have already finished a rescue treatment also including rituximab. Immunohistochemical assessment of Bcl-2, Bcl-6, p53, and MUM1 expression were undertaken in available biopsies. R-IPI factors were identified from the clinical data at diagnosis and at relapse. Response was assessed using National Cancer Institute-sponsored Working Group guidelines.

RESULTS

R-IPI prognosis at relapse was not significantly associated with overall response rate (ORR) after Rituximab-chemotherapy rescue therapy. None of the immunohistochemical parameters analyzed correlated with rescue therapy results. In contrast, patients with absolute lymphocyte count (ALC) ≥ 1 × 10(9)/L at relapse were more likely to respond than patients with ALC < 1 × 10(9)/L (P = .05).

CONCLUSION

The R-IPI score calculated at relapse could not predict the ORR to second-line treatment. Lymphopenia is a simple and useful predictor for outcome in relapsed/refractory DLBCL and the only prognostic factor that in our hands could predict the overall response to a second-line treatment with rituximab and chemotherapy.

Management of diffuse large B-cell lymphoma (DLBCL)

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma. While CHOP was the standard combination chemotherapy for 25 years, the incorporation of the CD20 antibody rituximab at the beginning of this century has considerably improved the outcome of all patients with DLBCL: Depending on the prognostic subgroup, only half to one-third of the patients die of their DLBCL compared to pre-rituximab era. Treatment is usually tailored according to the individual risk profile of a DLBCL patient according to the International Prognostic Index (IPI). Assignment of DLBCL according to the gene expression profile into DLBLC originating from a germinal center B cell (GC type) or from an activated B cell (ABC type) has provided novel insights into the pathogenesis of the respective DLBCL, identified molecules which are indispensable for the survival of the lymphoma cells and provided targets for novel "targeted therapies" drugs. Incorporating these new drugs into combination immunochemotherapy or substituting single drugs in the R-CHOP combination will result in even higher cure rates of and/or less toxicity for patients with DLBCL in the decade to come.

Pathology of follicular lymphoma

Follicular lymphoma (FL) is a heterogeneous disease, and there are many different subgroups, such as in terms of age of onset, involved organ (especially extranodal sites such as gastrointestinal tract) and genetic abnormality. Grade 3B is currently regarded as a distinct entity by molecular genetic analyses, but the independence of Grade 3A remains unclear. Variations of clinical course are known in FL. Some cases are very indolent, but others are not. The latter cases show histological transformation to diffuse large B-cell lymphoma (DLBCL) (high-grade transformation) and an aggressive course. Histological transformation to DLBCL is reported to occur in about 30-40% of patients, at a rate of about 3% each year. However, it reaches a plateau at about 16 years, so the stratification of patients in whom transformation would or would not occur is very important for the therapeutic strategy. From genome-wide analysis by next-generation sequencing, EZH2, CREBBP and MLL2, which are histone-modifying genes, have been shown to be frequently mutated in FL and to have an important role in lymphomagenesis. IGH-BCL2 translocation and CREBBP mutations are early events, whereas MLL2 and TNFSFR14 mutations represent late events during disease evolution. In the 2008 WHO classification, three new variants: (1) pediatric follicular lymphoma, (2) primary intestinal follicular lymphoma and (3) in situ follicular lymphoma, are included. Pathologists and clinicians should consider these new developments when deciding on the diagnostic and therapeutic strategy.

The DNA methylome: a novel biomarker

In this issue of Blood, Chambwe and colleagues demonstrate the presence of promoter methylation variability in diffuse large B-cell lymphomas (DLBCLs).1 This methylation variability correlates with the expression of specific genes and is associated with distinct survival following standard therapy—a finding that has numerous implications for our understanding of the pathogenesis of these tumors.

Sex- and subtype-specific analysis of H2AFX polymorphisms in non-Hodgkin lymphoma

H2AFX encodes a histone variant involved in signaling sites of DNA damage and recruiting repair factors. Genetic variants in H2AFX may influence risk of non-Hodgkin lymphoma (NHL), a heterogeneous group of lymphoid tumors that are characterized by chromosomal translocations. We previously reported that rs2509049, a common variant in the promoter of H2AFX, was associated with risk for NHL in the British Columbia population. Here we report results for 13 single nucleotide polymorphisms (SNPs) in 100 Kb surrounding H2AFX in an expanded collection of 568 NHL cases and 547 controls. After correction for multiple testing, significant associations were present for mantle cell lymphoma (p=0.007 for rs604714) and all B-cell lymphomas (p=0.046 for rs2509049). Strong linkage disequilibrium in the 5 Kb upstream of H2AFX limited the ability to determine which specific SNP (rs2509049, rs7759, rs8551, rs643788, rs604714, or rs603826), if any, was responsible. There was a significant interaction between sex and rs2509049 in the all B-cell lymphomas group (p=0.002); a sex-stratified analysis revealed that the association was confined to females (p=0.001). Neither the overall nor the female-specific association with rs2509049 was replicated in any of four independent NHL sample sets. Meta-analysis of all five study populations (3,882 B-cell NHL cases and 3,718 controls) supported a weak association with B-cell lymphoma (OR=0.92, 95% CI=0.86-0.99, p=0.034), although this association was not significant after exclusion of the British Columbia data. Further research into the potential sex-specificity of the H2AFX-NHL association may identify a subset of NHL cases that are influenced by genotype at this locus.

The 3q27 and 18q21 translocations for follicular lymphoma and diffuse large B-cell lymphoma in the rituximab era

The 3q27 and 18q21 chromosomal translocations are major hallmarks in B-cell lymphoma. We aimed to determine the frequencies of these translocations in follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) and to evaluate their prognostic impact in the rituximab era. This study included 98 FL and 93 DLBCL patients whose abnormal karyotypes had been detected using G-banding. Patients uniformly underwent R-CHOP therapy : doxorubicin, cyclophosphamide, vincristine, prednisolone, and rituximab ; survivors were followed up for 29 months (median). The 3q27 and 18q21 translocations were detected in 14 and 77 FL patients and 14 and 22 DLBCL patients, respectively. Overall survival (OS) and progression-free survival (PFS) did not differ significantly between the groups with 3q27, 18q21, concurrent 3q27 and 18q21 translocations, and other chromosomal abnormalities for FL and DLBCL. There were no significant differences in OS and PFS between patients with 3q27 translocation-positive FL and those with 3q27 translocation-positive DLBCL or between the patients with 18q21 translocation-positive FL and those with 18q21 translocation-positive DLBCL. The presence of 3q27 and 18q21 translocations did not correlate with the clinical outcomes of FL or DLBCL patients following R-CHOP treatment.

Diffuse large B-cell lymphoma and mantle cell lymphoma of the ocular adnexal region, and lymphoma of the lacrimal gland: an investigation of clinical and histopathological features

Diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma (MCL) constitute two distinct subtypes of non-Hodgkin lymphoma (NHL) associated with considerable morbidity and mortality. Marked diversities with regard to molecular biology and clinical features are recognized in different subsets of the two lymphomas. Because these differences could be related to the location of the lymphoma, it is of interest to investigate the clinical and histopathological features of DLBCL and MCL involving the ocular adnexal region (i.e. the orbit, eyelids, conjunctiva, lacrimal gland and lacrimal sac). Similarly, the lacrimal gland is the only glandular structure within the orbit. Because the lacrimal gland represents an important part of the immunological system, it is of interest to investigate lymphomas involving this location with regard to clinical and histological characteristics.

PURPOSE

  To characterize the clinical and histopathological features of Danish patients with DLBCL of the ocular adnexal region between 1980 and 2009 and of Danish ocular adnexal MCL patients from 1980 to 2005. Furthermore, the aim of this PhD was to review all specimens from patients with lymphoma of the lacrimal gland in Denmark between 1975 and 2009 to determine the distribution of lymphoma subtypes of the lacrimal gland and to describe the clinicopathological features of these patients.

RESULTS

  A total of 34 patients with DLBCL and 21 with MCL of the ocular adnexal region were identified. Twenty-seven patients had lacrimal gland lymphoma, including four DLBCLs and three MCLs from studies I and II. Elderly patients predominated in all three groups, with median ages of 78, 75 and 69 years in the DLBCL, the MCL and the lacrimal gland lymphoma groups, respectively. MCL patients had a preponderance of males, whereas females prevailed among lacrimal gland lymphoma patients. The orbit was the most common site of involvement in DLBCL and MCL. Most DLBCL patients had unilateral involvement, while MCL patients had a high frequency of bilateral involvement. Similarly, localized lymphoma was relatively frequently seen in DLBCL patients in contrast to the predominance of disseminated lymphoma in the MCL group. The majority of lacrimal gland lymphomas were low grade, and the distribution of subtypes was as follows: extranodal marginal zone lymphoma, 10 (37%); follicular lymphoma, 5 (19%); DLBCL, 4 (15%); MCL, 3 (11%); chronic lymphocytic leukaemia/small lymphatic lymphoma, 2 (7%); and unclassified B-cell lymphoma, 3 (11%). The overall survival rates at 3 and 5 years for the entire study group of DLBCL were 42% and 20%, whereas 58% and 22% of MCL patients were alive 3 and 5 years after the time of diagnosis. The 5-year overall survival rate of lacrimal gland lymphoma patients was 70%. Concordant bone marrow involvement and the International Prognostic Index score were predictive factors for the overall survival in the DLBCL group in Cox regression analysis. Rituximab-containing chemotherapy was associated with an improved survival rate in MCL patients.

CONCLUSIONS

  Diffuse large B-cell lymphoma and MCL involving the ocular adnexal region and lymphoma of the lacrimal gland are prevalent among elderly patients. The overall prognosis in DLBCL and MCL was poor, whereas the prognosis for lacrimal gland lymphoma patients was relatively good. Concordant bone marrow involvement and the International Prognostic Index score were independent predictive factors for mortality in the DLBCL group. Chemotherapy containing rituximab significantly improved survival in the MCL group.

Diffuse large B-cell lymphoma of the ocular adnexal region: a nation-based study

PURPOSE

To characterize the clinicopathological features of diffuse large B-cell lymphoma (DLBCL) of the ocular adnexal region.

METHODS

The present series of orbital and adnexal DLBCLs were found by searching the Danish Registry of Pathology between 1980 and 2009. Histological specimens were re-evaluated using a panel of monoclonal antibodies. Clinical files from all patients with confirmed DLBCL were collected.

RESULTS

A total of 34 patients with DLBCL of the ocular adnexal region were identified. Eighteen of the patients were men. The patients had a median age of 78 years (range 35-97 years). Ninety-seven per cent of the patients had unilateral ocular adnexal region involvement, and the orbit (76%) was the most frequently affected site. Nineteen patients (56%) presented with Stage I lymphoma. Of these, 18 were diagnosed with primary lymphoma. Four patients (12%) had Stage II, one patient (3%) had Stage III and ten patients (29%) presented with Stage IV lymphoma. The 5-year overall survival (OS) rate for the whole study group was 20%. The patients with Stage I lymphoma had a significantly better 5-year OS rate (28%) than patients in Stage II-IV (5-year OS rate, 9%). In Cox regression analysis, concordant bone marrow involvement and the International Prognostic Index (IPI) score were prognostic factors for OS.

CONCLUSIONS

Diffuse large B-cell lymphoma of the ocular adnexal region is mainly prevalent in elderly patients. Most patients had unilateral orbital involvement. The overall prognosis is poor. Concordant bone marrow involvement and the IPI score were independent prognostic factors for mortality.

Pathophysiology and molecular aspects of diffuse large B-cell lymphoma

Diffuse large B-Cell lymphoma is the most common subtype of non-Hodgkin lymphoma in the West. In Brazil, it is the fifth cause of cancer, with more than 55,000 cases and 26,000 deaths per year. At Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo - HCFMUSP, diffuse large B-Cell lymphoma represents 49.7% of all non-Hodgkin lymphoma cases. Initially, the classification of non-Hodgkin lymphoma was based on morphology, but advances in immunology and molecular medicine allowed the introduction of a biological classification for these diseases. As for other cancers, non-Hodgkin lymphoma involves patterns of multifactorial pathogenesis with environmental factors, as well as genetic, occupational and dietary factors, contributing to its development. Multiple lesions involving molecular pathways of B-cell proliferation and differentiation may result in the activation of oncogenes such as the BCL2, BCL6, and MYC genes and the inactivation of tumor suppressor genes such as p53 and INK4, as well as other important transcription factors such as OCT-1 and OCT-2. A dramatic improvement in survival was seen after the recent introduction of the anti-CD20 monoclonal antibody. The association of this antibody to the cyclophosphamide, hydroxydaunorubicin, oncovin and prednisolone (CHOP) regimen has increased overall survival of diffuse large B-Cell lymphoma and follicular lymphoma patients by 20%. However, 50% of all diffuse large B-Cell lymphoma patients remain incurable, creating a demand for more research with new advances in treatment. Thus, it is important to know and understand the key factors and molecular pathways involved in the pathogenesis of diffuse large B-Cell lymphoma.

Cytogenetics and molecular cytogenetics in diffuse large B-cell lymphoma (DLBCL)

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) accounts for up to 40% of all non-Hodgkin's lymphomas diagnosed in the western hemisphere. Determination of the gene expression profile has confirmed the physiological heterogeneity of the disease and defined three molecular prognostic subgroups - germinal center B-cell-like (GCB), activated B-cell-like (ABC) and primary mediastinal B-cell lymphoma (PMBL) - with different gene expression and prognosis.

METHODS AND RESULTS

This review covers current knowledge on the most frequent recurrent cytogenetic and molecular cytogenetic aberrations in molecular DLBCL subgroups.

CONCLUSIONS

Cytogenetic and molecular cytogenetic techniques used to determine nonrandom chromosomal aberrations in patients with DLBCL have revealed the incidence of frequent cytogenetic aberrations in the subgroups reported, suggesting their potential use for more accurate prognostic stratification of DLBCL, contributing to personalized selection of the most effective therapy.