Mantle cell lymphoma: evolving management strategies

Prognostic and survival factors in head and neck extra-nodal non-Hodgkin's lymphoma

OBJECTIVE

To make a clinical-biological characterization of this pathology and assess the survival of these patients and the associated prognostic factors.

STUDY DESIGN

A retrospective observational study was designed to identify primary extranodal non-Hodgkin lymphomas of the head and neck diagnosed between January 1, 2005, and January 1, 2016. Cases were considered if they presented with a single tumor in situ or if the extranodal component was clinically predominant.

RESULTS

A total of 145 patients were included. Localized stages (I-II) were present in 69.3%. Overall, 91.8% were B-cell phenotype, with diffuse large B-cell lymphoma being the most frequent. Overall, 78% of patients were treated with immunochemotherapy. The overall survival at 3 and 5 years was 75% and 73%, respectively. Adverse prognostic factors were: low hemoglobin, elevated ß2-microglobulin, and lactate dehydrogenase (LDH) levels, Eastern Cooperative Oncology Group (ECOG), stage III/IV, and B symptomatology at diagnosis. The progression-free survival at 3 and 5 years was 71% and 68%. Risk factors for relapse were high ß2-microglobulin, high LDH, and stage III-IV at diagnosis.

CONCLUSIONS

These pathologies show a good response to treatment with immuno-polychemotherapy. Factors associated with a worse prognosis included low hemoglobin, elevated levels of ß2-microglobulin and LDH, elevated ECOG, stage III/IV, and B symptomatology at diagnosis.

Relapsed mantle cell lymphoma manifesting with soft tissue tumors of the extremities: University of Miami experience and review of the literature

Mantle cell lymphoma (MCL) is frequently diagnosed at advanced stages and is characterized by multiple extranodal sites of disease, most notably the bone marrow, peripheral blood, and gastrointestinal tract. Historically the prognosis of mantle cell lymphoma has been poor with median survival of four to five years. With new treatment regimens, however, patients have been able to achieve prolonged remissions and require special attention while being evaluated for relapse. This report describes four patients treated for stage IV mantle cell lymphoma at the University of Miami who developed soft tissue relapse presenting as non-tender large masses of the extremities, including one patient who presented without associated nodal involvement. Average time to soft tissue relapse was 99 months (range: 28-240) following initial diagnosis. Providers who care for patients with mantle cell lymphoma should be aware of soft tissue lesions as a presentation of mantle cell lymphoma that merits evaluation for disease relapse.

Mantle Cell Lymphoma Under the Scope of Personalized Medicine: Perspective and Directions

Mantle cell lymphoma (MCL) is a rare, incurable non-Hodgkin's lymphoma characterized by naive B cells infiltrating the lymphoid follicle's mantle zone. A key feature of MCL is the cytogenetic abnormality t(11;14) (q13:q14), found in 95% of cases, leading to Cyclin D1 overexpression resulting in uncontrolled cell cycle progression and genetic instability. Occasionally, Cyclin D2 or D3 overexpression can substitute for Cyclin D1, causing similar effects. The transcription factor SOX11 is a hallmark of classical Cyclin D1-positive MCL and also in cases without the typical t(11;14) abnormality, making it an important diagnostic marker. MCL's development necessitates secondary genetic changes, including mutations in the ATM, TP53, and NOTCH1 genes, with the TP53 mutation being the only genetic biomarker with established clinical prognostic value. The Mantle Cell Lymphoma International Prognostic Index (MIPI) score, which considers age, performance status, serum LDH levels, and leukocyte count, stratifies patients into risk groups. Histologic variants of MCL, such as classic, blastoid, and pleomorphic, offer additional prognostic information. Recent research highlights new mutations potentially tied to specific populations among MCL patients, suggesting the benefit of personalized management for better predicting outcomes like progression-free survival. This approach could lead to more effective, risk-adapted treatment strategies. However, challenges remain in patient stratification and in developing new therapeutic targets for MCL. This review synthesizes current knowledge on genetic mutations in MCL and their impact on prognosis. It aims to explore the prognostic value of genetic markers related to population traits, emphasizing the importance of tailored molecular medicine in MCL.

An atlas of cells in the human tonsil

Palatine tonsils are secondary lymphoid organs (SLOs) representing the first line of immunological defense against inhaled or ingested pathogens. We generated an atlas of the human tonsil composed of >556,000 cells profiled across five different data modalities, including single-cell transcriptome, epigenome, proteome, and immune repertoire sequencing, as well as spatial transcriptomics. This census identified 121 cell types and states, defined developmental trajectories, and enabled an understanding of the functional units of the tonsil. Exemplarily, we stratified myeloid slan-like subtypes, established a BCL6 enhancer as locally active in follicle-associated T and B cells, and identified SIX5 as putative transcriptional regulator of plasma cell maturation. Analyses of a validation cohort confirmed the presence, annotation, and markers of tonsillar cell types and provided evidence of age-related compositional shifts. We demonstrate the value of this resource by annotating cells from B cell-derived mantle cell lymphomas, linking transcriptional heterogeneity to normal B cell differentiation states of the human tonsil.

Nano-scale delivery systems for siRNA delivery in cancer therapy: New era of gene therapy empowered by nanotechnology

RNA interference (RNAi) is a unique treatment approach used to decrease a disease's excessive gene expression, including cancer. SiRNAs may find and destroy homologous mRNA sequences within the cell thanks to RNAi processes. However, difficulties such poor cellular uptake, off-target effects, and susceptibility to destruction by serum nucleases in the bloodstream restrict the therapeutic potential of siRNAs. Since some years ago, siRNA-based therapies have been in the process of being translated into the clinic. Therefore, the primary emphasis of this work is on sophisticated nanocarriers that aid in the transport of siRNA payloads, their administration in combination with anticancer medications, and their use in the treatment of cancer. The research looks into molecular manifestations, difficulties with siRNA transport, the design and development of siRNA-based delivery methods, and the benefits and drawbacks of various nanocarriers. The trapping of siRNA in endosomes is a challenge for the majority of delivery methods, which affects the therapeutic effectiveness. Numerous techniques for siRNA release, including as pH-responsive release, membrane fusion, the proton sponge effect, and photochemical disruption, have been studied to overcome this problem. The present state of siRNA treatments in clinical trials is also looked at in order to give a thorough and systematic evaluation of siRNA-based medicines for efficient cancer therapy.

Infrared Spectroscopy: A New Frontier in Hematological Disease Diagnosis

Hematological diseases, due to their complex nature and diverse manifestations, pose significant diagnostic challenges in healthcare. The pressing need for early and accurate diagnosis has driven the exploration of novel diagnostic techniques. Infrared (IR) spectroscopy, renowned for its noninvasive, rapid, and cost-effective characteristics, has emerged as a promising adjunct in hematological diagnostics. This review delves into the transformative role of IR spectroscopy and highlights its applications in detecting and diagnosing various blood-related ailments. We discuss groundbreaking research findings and real-world applications while providing a balanced view of the potential and limitations of the technique. By integrating advanced technology with clinical needs, we offer insights into how IR spectroscopy may herald a new era of hematological disease diagnosis.

A novel CAR-T cell product targeting CD74 is an effective therapeutic approach in preclinical mantle cell lymphoma models

BACKGROUND

Mantle cell lymphoma (MCL) is a rare B-cell non-Hodgkin lymphoma subtype which remains incurable despite multimodal approach including chemoimmunotherapy followed by stem cell transplant, targeted approaches such as the BTK inhibitor ibrutinib, and CD19 chimeric antigen receptor (CAR) T cells. CD74 is a nonpolymorphic type II integral membrane glycoprotein identified as an MHC class II chaperone and a receptor for macrophage migration inhibitory factor. Our group previously reported on CD74's abundant expression in MCL and its ability to increase via pharmacological inhibition of autophagosomal degradation. Milatuzumab, a fully humanized anti-CD74 monoclonal antibody, demonstrated significant activity in preclinical lymphoma models but failed to provide meaningful benefits in clinical trials mainly due to its short half-life. We hypothesized that targeting CD74 using a CAR-T cell would provide potent and durable anti-MCL activity.

METHODS

We engineered a second generation anti-CD74 CAR with 4-1BB and CD3ζ signaling domains (74bbz). Through in silico and rational mutagenesis on the scFV domain, the 74bbz CAR was functionally optimized for superior antigen binding affinity, proliferative signaling, and cytotoxic activity against MCL cells in vitro and in vivo.

RESULTS

Functionally optimized 74bbz CAR-T cells (clone 42105) induced significant killing of MCL cell lines, and primary MCL patient samples including one relapse after commercial CD19 CAR-T cell therapy with direct correlation between antigen density and cytotoxicity. It significantly prolonged the survival of an animal model established in NOD-SCIDγc-/- (NSG) mice engrafted with a human MCL cell line Mino subcutaneously compared to controls. Finally, while CD74 is also expressed on normal immune cell subsets, treatment with 74bbz CAR-T cells resulted in minimal cytotoxicity against these cells both in vitro and in vivo.

CONCLUSIONS

Targeting CD74 with 74bbz CAR-T cells represents a new cell therapy to provide a potent and durable and anti-MCL activity.

MicroRNA therapeutics and nucleic acid nano-delivery systems in bacterial infection: a review

Bacteria that have worked with humans for thousands of years pose a major threat to human health even today, as drug resistance has become a prominent problem. Compared to conventional drug therapy, nucleic acid-based therapies are a promising and potential therapeutic strategy for diseases in which nucleic acids are delivered through a nucleic acid delivery system to regulate gene expression in specific cells, offering the possibility of curing intractable diseases that are difficult to treat at this stage. Among the many nucleic acid therapeutic ideas, microRNA, a class of small nucleic acids with special properties, has made great strides in biology and medicine in just over two decades, showing promise in preclinical drug development. In this review, we introduce recent advances in nucleic acid delivery systems and their clinical applications, highlighting the potential of nucleic acid therapies, especially miRNAs extracted from traditional herbs, in combination with the existing set of nucleic acid therapeutic systems, to potentially open up a new line of thought in the treatment of cancer, viruses, and especially bacterial infectious diseases.

Real-world treatment and outcome patterns of patients with mantle cell lymphoma in China: A large, multicenter retrospective analysis

BACKGROUND

Mantle cell lymphoma (MCL) is an uncommon heterogeneous subtype of B cell non-Hodgkin lymphoma, and clinical features in MCL appear regional characteristics. MCL treatment opinions are not uniform between countries or regions within Asia and China, and Asian patient-specific data for MCL treatment are fewer. The study aims to explore the clinical characteristics, treatment patterns and prognosis of MCL patients in China.

METHODS

A total of 805 patients diagnosed with MCL between April 1999 and December 2019 at 19 comprehensive hospitals in China were included in this retrospective analysis. Kaplan-Meier method coupled with the log-rank test was used for univariate analysis, and COX proportional hazards model was used for multivariate analysis (MVA). p < 0.05 was consided statistically significant. All outputs were produced using R version 4.1.0.

RESULTS

The median age of the cohort was 60.0 years with a male-to-female ratio of 3.36:1. Five-year progression-free survival (PFS) and overall survival (OS) rates were 30.9% and 65.0%, respectively. High-intermediate/high-risk group according to MIPI-c, without high-dose cytarabine, lack of Auto-SCT as consolidation and maintenance treatment and SD/PD in initial treatment remained statistically relevant to poor PFS on MVA, and ki67 ≥50%, B symptoms, high-intermediate/high risk group according to MIPI-c, without high-dose cytarabine, lack of maintenance treatment, SD/PD in initial treatment and relapse/refractory state were independently associated with poorer OS on MVA.

CONCLUSIONS

First-line high dose cytarabine exposure, auto-SCT as consolidation therapy obtained survival benefits in Chinese population. Our study further confirmed the value of maintenance treatment and explored the application of new drug treatment and bendamustine in R/R MCL patients.

First Report of FARSA in the Regulation of Cell Cycle and Survival in Mantle Cell Lymphoma Cells via PI3K-AKT and FOXO1-RAG1 Axes

Cancer-associated factors have been largely identified in the understanding of tumorigenesis and progression. However, aminoacyl-transfer RNA (tRNA) synthetases (aaRSs) have so far been neglected in cancer research due to their canonical activities in protein translation and synthesis. FARSA, the alpha subunit of the phenylalanyl-tRNA synthetase is elevated across many cancer types, but its function in mantle cell lymphoma (MCL) remains undetermined. Herein, we found the lowest levels of FARSA in patients with MCL compared with other subtypes of lymphomas, and the same lower levels of FARSA were observed in chemoresistant MCL cell lines. Unexpectedly, despite the essential catalytic roles of FARSA, knockdown of FARSA in MCL cells did not lead to cell death but resulted in accelerated cell proliferation and cell cycle, whereas overexpression of FARSA induced remarkable cell-cycle arrest and overwhelming apoptosis. Further RNA sequencing (RNA-seq) analysis and validation experiments confirmed a strong connection between FARSA and cell cycle in MCL cells. Importantly, FARSA leads to the alteration of cell cycle and survival via both PI3K-AKT and FOXO1-RAG1 axes, highlighting a FARSA-mediated regulatory network in MCL cells. Our findings, for the first time, reveal the noncanonical roles of FARSA in MCL cells, and provide novel insights into understanding the pathogenesis and progression of B-cell malignancies.

The IL32/BAFF axis supports prosurvival dialogs in the lymphoma ecosystem and is disrupted by NIK inhibition

Aggressive B-cell malignancies, such as mantle cell lymphoma (MCL), are microenvironment-dependent tumors and a better understanding of the dialogs occurring in lymphoma-protective ecosystems will provide new perspectives to increase treatment efficiency. To identify novel molecular regulations, we performed a transcriptomic analysis based on the comparison of circulating MCL cells (n=77) versus MCL lymph nodes (n=107) together with RNA sequencing of malignant (n=8) versus normal B-cell (n=6) samples. This integrated analysis led to the discovery of microenvironment-dependent and tumor-specific secretion of interleukin-32 beta (IL32β), whose expression was confirmed in situ within MCL lymph nodes by multiplex immunohistochemistry. Using ex vivo models of primary MCL cells (n=23), we demonstrated that, through the secretion of IL32β, the tumor was able to polarize monocytes into specific MCL-associated macrophages, which in turn favor tumor survival. We highlighted that while IL32β-stimulated macrophages secreted several protumoral factors, they supported tumor survival through a soluble dialog, mostly driven by BAFF. Finally, we demonstrated the efficacy of selective NIK/alternative-NFkB inhibition to counteract microenvironment-dependent induction of IL32β and BAFF-dependent survival of MCL cells. These data uncovered the IL32β/BAFF axis as a previously undescribed pathway involved in lymphoma-associated macrophage polarization and tumor survival, which could be counteracted through selective NIK inhibition.

Antitumor Activity of Simvastatin in Preclinical Models of Mantle Cell Lymphoma

BACKGROUND

Mantle cell lymphoma (MCL) is a rare and aggressive subtype of B-cell non-Hodgkin lymphoma that remains incurable with standard therapy. Statins are well-tolerated, inexpensive, and widely prescribed as cholesterol-lowering agents to treat hyperlipidemia and to prevent cardiovascular diseases through the blockage of the mevalonate metabolic pathway. These drugs have also shown promising anti-cancer activity through pleiotropic effects including the induction of lymphoma cell death. However, their potential use as anti-MCL agents has not been evaluated so far.

AIM

The present study aimed to investigate the activity of simvastatin on MCL cells.

METHODS

We evaluated the cytotoxicity of simvastatin in MCL cell lines by CellTiter-Glo and lactate dehydrogenase (LDH) release assays. Cell proliferation and mitotic index were assessed by direct cell recounting and histone H3-pSer10 immunostaining. Apoptosis induction and reactive oxygen species (ROS) generation were evaluated by flow cytometry. Cell migration and invasion properties were determined by transwell assay. The antitumoral effect of simvastatin in vivo was evaluated in a chick embryo chorioallantoic membrane (CAM) MCL xenograft model.

RESULTS

We show that treatment with simvastatin induced a 2 to 6-fold LDH release, inhibited more than 50% of cell proliferation, and enhanced the caspase-independent ROS-mediated death of MCL cells. The effective impairment of MCL cell survival was accompanied by the inhibition of AKT and mTOR phosphorylation. Moreover, simvastatin strongly decreased MCL cell migration and invasion ability, leading to a 55% tumor growth inhibition and a consistent diminution of bone marrow and spleen metastasis in vivo.

CONCLUSION

Altogether, these data provide the first preclinical insight into the effect of simvastatin against MCL cells, suggesting that this agent might be considered for repurpose as a precise MCL therapy.

Ibrutinib improves survival compared with chemotherapy in mantle cell lymphoma with central nervous system relapse

Central nervous system (CNS) relapse of mantle cell lymphoma (MCL) is a rare phenomenon with dismal prognosis, where no standard therapy exists. Since the covalent Bruton tyrosine kinase (BTK) inhibitor ibrutinib is effective in relapsed/refractory MCL and penetrates the blood-brain barrier (BBB), on behalf of Fondazione Italiana Linfomi and European Mantle Cell Lymphoma Network we performed a multicenter retrospective international study to investigate the outcomes of patients treated with ibrutinib or chemoimmunotherapy. In this observational study, we recruited patients with MCL with CNS involvement at relapse who received CNS-directed therapy between 2000 and 2019. The primary objective was to compare the overall survival (OS) of patients treated with ibrutinib or BBB crossing chemotherapy. A propensity score based on a multivariable binary regression model was applied to balance treatment cohorts. Eighty-eight patients were included. The median age at study entry was 65 years (range, 39-87), 76% were males, and the median time from lymphoma diagnosis to CNS relapse was 16 months (range, 1-122). Patients were treated with ibrutinib (n = 29, ibrutinib cohort), BBB crossing chemotherapy (ie, high-dose methotrexate ± cytarabine; n = 29, BBB cohort), or miscellaneous treatments (n = 30, other therapy cohort). Both median OS (16.8 vs 4.4 months; P = .007) and median progression-free survival (PFS) (13.1 vs 3.0 months; P = .009) were superior in the ibrutinib cohort compared with the BBB cohort. Multivariable Cox regression model revealed that ibrutinib therapeutic choice was the strongest independent favorable predictive factor for both OS (hazard ratio [HR], 6.8; 95% confidence interval [CI], 2.2-21.3; P < .001) and PFS (HR, 4.6; 95% CI, 1.7-12.5; P = .002), followed by CNS progression of disease (POD) >24 months from first MCL diagnosis (HR for death, 2.4; 95% CI, 1.1-5.3; P = .026; HR for death or progression, 2.3; 95% CI, 1.1-4.6; P = .023). The addition of intrathecal (IT) chemotherapy to systemic CNS-directed therapy was not associated with superior OS (P = .502) as the morphological variant (classical vs others, P = .118). Ibrutinib was associated with superior survival compared with BBB-penetrating chemotherapy in patients with CNS relapse of MCL and should be considered as a therapeutic option.

Autophagy in Hematological Malignancies

Simple Summary

Autophagy is a dynamic and tightly regulated process that seems to have dual effects in cancer. In some contexts, it can induce carcinogenesis and promote cancer cell survival, whereas in others, it acts preventing tumor cell growth and tumor progression. Thus, autophagy functions seem to strictly depend on cancer ontogenesis, progression, and type. Here, we will dive into the current knowledge of autophagy in hematological malignancies and will highlight the main genetic components involved in each cancer type.

Abstract

Autophagy is a highly conserved metabolic pathway via which unwanted intracellular materials, such as unfolded proteins or damaged organelles, are digested. It is activated in response to conditions of oxidative stress or starvation, and is essential for the maintenance of cellular homeostasis and other vital functions, such as differentiation, cell death, and the cell cycle. Therefore, autophagy plays an important role in the initiation and progression of tumors, including hematological malignancies, where damaged autophagy during hematopoiesis can cause malignant transformation and increase cell proliferation. Over the last decade, the importance of autophagy in response to standard pharmacological treatment of hematological tumors has been observed, revealing completely opposite roles depending on the tumor type and stage. Thus, autophagy can promote tumor survival by attenuating the cellular damage caused by drugs and/or stabilizing oncogenic proteins, but can also have an antitumoral effect due to autophagic cell death. Therefore, autophagy-based strategies must depend on the context to create specific and safe combination therapies that could contribute to improved clinical outcomes. In this review, we describe the process of autophagy and its role on hematopoiesis, and we highlight recent research investigating its role as a potential therapeutic target in hematological malignancies. The findings suggest that genetic variants within autophagy-related genes modulate the risk of developing hemopathies, as well as patient survival.

USP9X Increased Tumor Angiogenesis in Mantle Cell Lymphoma by Upregulation of CCND1-Mediated SOX11

Mantle cell lymphoma (MCL) is an aggressive lymphoid malignancy with a poor prognosis. Ubiquitin-specific peptidase 9, X-linked (USP9X), has been associated with multiple physiological pathways and regulates various cellular activities. In this study, we explored the role of USP9X in MCL in vitro and in vivo. USP9X was verified to be increased in peripheral blood mononuclear cells (PBMCs) of MCL patients and MCL cells. Moreover, CCND1 and SOX11 were also upregulated in PBMCs of MCL patients. The positive correlation between USP9X and CCND1, USP9X and SOX11, and CCND1 and SOX11 were identified. Further, USP9X overexpression and knockdown were performed in MCL cells. We proved that USP9X overexpression promoted proliferation and cell cycle and suppressed cell apoptosis in MCL cells. Upregulation of angiogenesis and cell migration were induced by USP9X overexpression in MCL cells. However, the USP9X knockdown showed opposite effects. In addition, USP9X was discovered to decrease Cyclin D1 (CCND1)-mediated SOX11 expression in MCL cells. We demonstrated that SOX11 overexpression reversed USP9X knockdown-mediated angiogenesis in MCL cells. Besides, tumor formation was inhibited by USP9X knockdown in mice in vivo. In conclusion, these results revealed that USP9X promoted tumor angiogenesis in MCL via increasing CCND1-mediated SOX11.

First-Line Autologous Stem Cell Transplantation for Mantle Cell Lymphoma: A Systematic Analysis and Treatment Recommendation

Background

In the era of immunotherapy, autologous stem cell transplantation (ASCT) in first-line therapy in patients with mantle cell lymphoma (MCL) has been a controversial topic. This report aimed to explore the association between ASCT and MCL survival through a systematic review with meta-analysis.

Methods

We performed a systematic search of original articles published from inception to September 2021 using PubMed, MEDLINE, Embase, and Cochrane Library databases.

Results

We included studies that compared ASCT with non-ASCT consolidation in newly diagnosed transplant-eligible MCL. The endpoints were progression-free survival (PFS) and overall survival (OS). There were seven eligible studies (one randomized clinical trial, one prospective cohort study, and five observational studies) published between 2012 and 2021, in which the total number of participants was 3,271. In the non-intensive induction subgroup, patients with ASCT experienced a significant PFS but no OS benefit compared with those without ASCT. In the intensive induction subgroup, the PFS benefit from ASCT still existed but largely attenuated; no OS benefit was observed though only one study was suitable for evaluation. When compared to the rituximab maintenance arm, ASCT had a worse PFS and OS.

Conclusions

In the rituximab plus HiDAC era, the benefit of ASCT as a component of first-line treatment has been weakened. First-line maintenance strategy instead of ASCT seems worth exploring .

Cytological Diagnosis of Aggressive Small-Cell Lymphomas

BACKGROUND

Despite their sometimes deceivingly bland appearance, some small-cell lymphomas are very aggressive and the prognosis of patients depends on a prompt diagnosis that allows the initiation of appropriate therapy.

SUMMARY

The present review discusses the salient cytological features of the most common aggressive small-cell lymphomas and then proceeds to analyze their main diagnostic criteria, including the usage of ancillary techniques.

KEY MESSAGES

Lymph node fine-needle aspiration cytology is a fast, safe, cheap, minimally invasive, and accurate procedure that can be used for a prompt and accurate diagnosis of lymphomas.

Genomic and transcriptomic profiling reveals distinct molecular subsets associated with outcomes in mantle cell lymphoma

Mantle cell lymphoma (MCL) is a phenotypically and genetically heterogeneous malignancy in which the genetic alterations determining clinical indications are not fully understood. Here, we performed a comprehensive whole-exome sequencing analysis of 152 primary samples derived from 134 MCL patients, including longitudinal samples from 16 patients and matched RNA-Seq data from 48 samples. We classified MCL into 4 robust clusters (C1-C4). C1 featured mutated immunoglobulin heavy variable (IGHV), CCND1 mutation, amp(11q13), and active B cell receptor (BCR) signaling. C2 was enriched with del(11q)/ATM mutations and upregulation of NF-κB and DNA repair pathways. C3 was characterized by mutations in SP140, NOTCH1, and NSD2, with downregulation of BCR signaling and MYC targets. C4 harbored del(17p)/TP53 mutations, del(13q), and del(9p), and active MYC pathway and hyperproliferation signatures. Patients in these 4 clusters had distinct outcomes (5-year overall survival [OS] rates for C1-C4 were 100%, 56.7%, 48.7%, and 14.2%, respectively). We also inferred the temporal order of genetic events and studied clonal evolution of 16 patients before treatment and at progression/relapse. Eleven of these samples showed drastic clonal evolution that was associated with inferior survival, while the other samples showed modest or no evolution. Our study thus identifies genetic subsets that clinically define this malignancy and delineates clonal evolution patterns and their impact on clinical outcomes.

Cyclin D2 overexpression drives B1a-derived MCL-like lymphoma in mice

Mantle cell lymphoma (MCL) is an aggressive B cell lymphoma with poor long-term overall survival. Currently, MCL research and development of potential cures is hampered by the lack of good in vivo models. MCL is characterized by recurrent translocations of CCND1 or CCND2, resulting in overexpression of the cell cycle regulators cyclin D1 or D2, respectively. Here, we show, for the first time, that hematopoiesis-specific activation of cyclin D2 is sufficient to drive murine MCL-like lymphoma development. Furthermore, we demonstrate that cyclin D2 overexpression can synergize with loss of p53 to form aggressive and transplantable MCL-like lymphomas. Strikingly, cyclin D2-driven lymphomas display transcriptional, immunophenotypic, and functional similarities with B1a B cells. These MCL-like lymphomas have B1a-specific B cell receptors (BCRs), show elevated BCR and NF-κB pathway activation, and display increased MALT1 protease activity. Finally, we provide preclinical evidence that inhibition of MALT1 protease activity, which is essential for the development of early life-derived B1a cells, can be an effective therapeutic strategy to treat MCL.

Treatment Outcomes and Survival Patterns of Asian Patients With Relapsed/Refractory Mantle Cell Lymphoma

Background

Mantle cell lymphoma (MCL) is widely considered an incurable malignancy even with current therapies and relapsed/refractory (R/R) disease to primary treatment remains common. With improved treatment guidelines and the advent of novel agents, patients are increasingly being treated with more lines of regimens. However, outcomes after each line of treatment remain poorly characterized, especially in the Asian population. In this paper, we described the survival outcomes in a group of R/R MCL patients.

Methods

We retrospectively studied 35 patients with R/R MCL between 1998 and 2020 at the National Cancer Centre Singapore. Patients were followed longitudinally throughout their disease course. Overall survival (OS) and progression-free survival (PFS) were determined by the Kaplan-Meier method.

Results

The median OS and PFS from diagnosis were 105 and 40 months, respectively. After first relapse, the median OS and PFS were 52 and 19 months, post-second relapse 32 and 8 months, and post-third relapse 12 and 6 months, respectively. Patients older than 65 years at first relapse had shorter survival (median OS: 22 vs. 55 months, P = 0.0417; median PFS: 9 vs. 29 months, P = 0.001). Early treatment failure after first line therapy was also associated with worse survival outcomes (median OS: 13 vs. 55 months, P < 0.001; median PFS: 9 vs. 26 months, P < 0.001).

Conclusion

With each relapse, survival outcomes for patients with MCL are worse. Novel treatment and contemporary outcomes of R/R MCL are encouraging and support the need for continued research in this area.

G Protein-Coupled Estrogen Receptor Agonist G-1 Inhibits Mantle Cell Lymphoma Growth in Preclinical Models

Mantle cell lymphoma (MCL) is an aggressive form of non-Hodgkin’s B-cell lymphoma with poor prognosis. Despite recent advances, resistance to therapy and relapse remain significant clinical problems. G-protein-coupled estrogen receptor (GPER)-mediated estrogenic rapid signaling is implicated in the development of many cancers. However, its role in MCL is unknown. Here we report that GPER activation with selective agonist G-1 induced cell cycle arrest, DNA damage, mitochondria membrane potential abnormality, and eventually apoptosis of MCL cell lines. We found that G-1 induced DNA damage and apoptosis of MCL cells by promoting the expression of nicotinamide adenine dinucleotide phosphate oxidase and the generation of reactive oxygen species. In addition, G-1 inhibited MCL cell proliferation by inactivation of NF-κB signaling and exhibited anti-tumor functions in MCL xenografted mice. Most significantly, G-1 showed synergistic effect with ibrutinib making it a potential candidate for chemotherapy-free therapies against MCL.

Systematic Literature Review of Economic Evaluations, Costs/Resource Use, and Quality of Life in Patients with Mantle Cell Lymphoma

BACKGROUND

Mantle cell lymphoma (MCL) is a rare and aggressive subtype of non-Hodgkin's lymphoma. While treatment of patients with MCL and their outcomes are previously published, the availability of heath economics evidence is unclear.

OBJECTIVE

The aim of this paper was to conduct a comprehensive review of studies relating to economic evaluations, costs and resource use, and health-related quality of life (HRQoL) in patients with MCL.

METHODS

Search strategies were designed to capture studies reporting economic or HRQoL outcomes published in the previous 11 years (2007-2018). The following electronic databases were searched: MEDLINE, Embase, NHS Economic Evaluation Database (NHS EED), and EconLit. In addition, we reviewed congress abstracts presented over the previous 2 years (2015 and 2016; where 2017 proceedings had occurred, these were searched instead of 2015). Publications were screened in duplicate by two reviewers and supplementary searches were carried out on health technology assessment websites. Searches were first conducted in October 2017 and updated in March 2018.

FINDINGS

The systematic literature review identified 11 economic evaluations (in 16 publications), seven studies reporting data relating to costs or resource use, and five relating to HRQoL. Four economic evaluations presented results for patients with MCL modelled in the first-line setting, while seven modelled patients in the relapsed/refractory setting. The majority of economic evaluations were conducted using a Markov model with three to five health states. Seven studies assessed resource use and reported adverse events as key drivers of increased costs and resource use. Across the five studies reporting HRQoL, disparate measures were used. Two studies reported improvement in Functional Assessment of Cancer Therapy-Lymphoma (FACT-Lym) total scores following treatment and found that clinical response to treatment was associated with improvement in overall HRQoL.

CONCLUSIONS AND RELEVANCE

The published economic and HRQoL evidence in MCL, although scarce, reveals that the economic and HRQoL burden associated with MCL is substantial. In highlighting this evidence, this analysis underlines a critical unmet need for more effective treatments with improved outcomes in MCL.

3-Methyladenine but not antioxidants to overcome BACH2-mediated bortezomib resistance in mantle cell lymphoma

Background

Bortezomib (BTZ) is an inhibitor of the proteasome that has been used to treat patients with mantle cell lymphoma (MCL), but the resistance to BTZ in clinical cases remains a major drawback. BACH2 is a lymphoid-specific transcription repressor recognized as a tumor suppressor in MCL. Reduced BACH2 levels contribute to BTZ resistance; however, the molecular events underlying BACH2-mediated BTZ resistance are largely unclear.

Methods

We silenced BACH2 in MCL cells using a lentiviral shRNA-mediated knockdown system. Bioinformatic, real-time RT-PCR, immunoblotting and a series of functional assays were performed to describe the molecular mechanisms underlying BTZ resistance in MCL. The therapeutic effects of chemicals were evaluated on numerous cellular and molecular processes in resistant MCL cell lines and xenografts.

Results

In resistant cells, BTZ-triggered mild oxidative stress induced a strong activation of PI3K-AKT signaling, which further blocked nuclear translocation of BACH2. Defective nuclear translocation of BACH2 or silencing BACH2 removed its transcriptional repression on HMOX1, leading to upregulation of heme oxygenase-1 (HO-1). Increased HO-1 further maintained reactive oxygen species (ROS) within a minimal tumor-promoting level and enhanced cytoprotective autophagy. Interestingly, although mild increase in ROS exhibited a pro-tumorigenic effect on resistant cells, simply blocking ROS by antioxidants did not lead to cell death but aggravated BTZ resistance via stabilizing BACH1, the other member of BACH family. Instead, 3-methyladenine (3-MA), a dual inhibitor to suppress PI3K signaling and autophagosome formation, sensitized resistant MCL cells to BTZ, both in vitro and in vivo.

Conclusion

Our results dissected the interconnected molecular network in resistant MCL cells in which 3-MA represents an effective therapeutic strategy to overcome BTZ resistance. Notably, BACH1 and BACH2, albeit from the same family, are likely to play opposite roles in pathogenesis and progression of MCL.

Association of minimal residual disease levels with clinical outcomes in patients with mantle cell lymphoma: A meta-analysis

Some studies have elucidated that Minimal residual disease (MRD) in patient with Mantle Cell Lymphoma (MCL) was a significant prognostic factor, with potential value in assessing overall survival (OS) and progression-free survival (PFS). However, most studies were widely varied in included population, sample sources and MRD detection time points. Some studies even have conflicting results. In view of this, a meta-analysis was performed to evaluate association of MRD levels with clinical outcomes in patients with MCL. We identified 7 included articles, which were published in recent 20 years. Then, we extracted or calculated hazard ratios (HRs) and their 95 % confidence intervals (CIs). Our results reveal that patients with MRD negativity have improved OS (HR = 0.63; 95 % CI: 0.50-0.79) and PFS (HR = 0.40, 95 % CI: 0.21-0.76), comparing with patients with MRD positivity. There are also consistent results in subgroups based on sample sources and MRD detection time points. Our study also demonstrates that MRD level is a strong prognostic factor of clinical outcomes. Thus, MRD is expected to be an effective clinical indicator for assessing prognosis and guide treatment decisions in MCL patients.

Ataxia-telangiectasia mutated interacts with Parkin and induces mitophagy independent of kinase activity. Evidence from mantle cell lymphoma

Ataxia telangiectasia mutated (ATM), a critical DNA damage sensor with protein kinase activity, is frequently altered in human cancers including mantle cell lymphoma. Loss of ATM protein is linked to accumulation of nonfunctional mitochondria and defective mitophagy in both murine thymocytes and in ataxia-telangiectasia cells. However, the mechanistic role of ATM kinase in cancer cell mitophagy is unknown. Here, we provide evidence that FCCP-induced mitophagy in mantle cell lymphoma and other cancer cell lines is dependent on ATM but independent of its kinase function. While Granta-519 mantle cell lymphoma cells possess single copy kinase-dead ATM and are resistant to FCCP-induced mitophagy, both Jeko-1 and Mino cells are ATMproficient and induce mitophagy. Stable knockdown of ATM in Jeko-1 and Mino cells conferred resistance to mitophagy and was associated with reduced ATP production, oxygen consumption, and increased mitochondrial reactive oxygen species. ATM interacts with the E3 ubiquitin ligase Parkin in a kinase-independent manner. Knockdown of ATM in HeLa cells resulted in proteasomal degradation of GFP-Parkin which was rescued by the proteasome inhibitor, MG132, suggesting that the ATMParkin interaction is important for Parkin stability. Neither loss of ATM kinase activity in primary B-cell lymphomas nor inhibition of ATM kinase in mantle cell lymphoma, ataxia-telangiectasia and HeLa cell lines mitigated FCCP- or CCCP-induced mitophagy suggesting that ATM kinase activity is dispensable for mitophagy. Malignant B-cell lymphomas without detectable ATM, Parkin, Pink1, and Parkin-Ub^Ser65 phosphorylation were resistant to mitophagy, providing the first molecular evidence of the role of ATM in mitophagy in mantle cell lymphoma and other B-cell lymphomas.

Survival Trends in Patients Under Age 65 Years With Mantle Cell Lymphoma, 1995-2016: A SEER-Based Analysis

Purpose: The treatment paradigm for mantle cell lymphoma (MCL), a B-cell malignancy, has shifted considerably during the past decades. This study aimed to evaluate time trends in overall survival (OS) and disease-specific mortality (DSM) of younger (age ≤ 65 years) patients with MCL from 1995 to 2016.

Methods: We used the Surveillance, Epidemiology, and End Results database. Year of diagnosis was divided into three eras: the chemotherapy-alone era (1995–2000), intensified-immunochemotherapy era (2001–2012), and targeted-therapy era (2013–2016). We used the Kaplan–Meier method, log-rank test, and subdistribution proportional hazard regression in the analysis.

Results: A total 4,892 patients were identified. Median OS increased from 67 months in the chemotherapy-alone era to 107 months in the intensified-immunochemotherapy era (P < 0.001). The DSM rate decreased significantly from 1995 to 2016 (P < 0.001); the adjusted hazard ratios of MCL-specific death were 0.589 (P < 0.001) for the intensified-immunochemotherapy era and 0.459 (P < 0.001) for targeted-therapy era, as compared with the chemotherapy-alone era. Patients with advanced-stage MCL exhibited lowering risk of death across the three eras (P < 0.001).

Conclusions: During 1995–2016, survival in younger patients with MCL increased significantly, especially those with advanced-stage disease, potentially reflecting the impact of advancement in treatment modalities on MCL outcome.

Genomic and epigenomic insights into the origin, pathogenesis, and clinical behavior of mantle cell lymphoma subtypes

Mantle cell lymphoma (MCL) is a mature B-cell neoplasm initially driven by CCND1 rearrangement with 2 molecular subtypes, conventional MCL (cMCL) and leukemic non-nodal MCL (nnMCL), that differ in their clinicobiological behavior. To identify the genetic and epigenetic alterations determining this diversity, we used whole-genome (n = 61) and exome (n = 21) sequencing (74% cMCL, 26% nnMCL) combined with transcriptome and DNA methylation profiles in the context of 5 MCL reference epigenomes. We identified that open and active chromatin at the major translocation cluster locus might facilitate the t(11;14)(q13;32), which modifies the 3-dimensional structure of the involved regions. This translocation is mainly acquired in precursor B cells mediated by recombination-activating genes in both MCL subtypes, whereas in 8% of cases the translocation occurs in mature B cells mediated by activation-induced cytidine deaminase. We identified novel recurrent MCL drivers, including CDKN1B, SAMHD1, BCOR, SYNE1, HNRNPH1, SMARCB1, and DAZAP1. Complex structural alterations emerge as a relevant early oncogenic mechanism in MCL, targeting key driver genes. Breakage-fusion-bridge cycles and translocations activated oncogenes (BMI1, MIR17HG, TERT, MYC, and MYCN), generating gene amplifications and remodeling regulatory regions. cMCL carried significant higher numbers of structural variants, copy number alterations, and driver changes than nnMCL, with exclusive alterations of ATM in cMCL, whereas TP53 and TERT alterations were slightly enriched in nnMCL. Several drivers had prognostic impact, but only TP53 and MYC aberrations added value independently of genomic complexity. An increasing genomic complexity, together with the presence of breakage-fusion-bridge cycles and high DNA methylation changes related to the proliferative cell history, defines patients with different clinical evolution.

The proteasome as a druggable target with multiple therapeutic potentialities: Cutting and non-cutting edges

Ubiquitin Proteasome System (UPS) is an adaptable and finely tuned system that sustains proteostasis network under a large variety of physiopathological conditions. Its dysregulation is often associated with the onset and progression of human diseases; hence, UPS modulation has emerged as a promising new avenue for the development of treatments of several relevant pathologies, such as cancer and neurodegeneration. The clinical interest in proteasome inhibition has considerably increased after the FDA approval in 2003 of bortezomib for relapsed/refractory multiple myeloma, which is now used in the front-line setting. Thereafter, two other proteasome inhibitors (carfilzomib and ixazomib), designed to overcome resistance to bortezomib, have been approved for treatment-experienced patients, and a variety of novel inhibitors are currently under preclinical and clinical investigation not only for haematological malignancies but also for solid tumours. However, since UPS collapse leads to toxic misfolded proteins accumulation, proteasome is attracting even more interest as a target for the care of neurodegenerative diseases, which are sustained by UPS impairment. Thus, conceptually, proteasome activation represents an innovative and largely unexplored target for drug development. According to a multidisciplinary approach, spanning from chemistry, biochemistry, molecular biology to pharmacology, this review will summarize the most recent available literature regarding different aspects of proteasome biology, focusing on structure, function and regulation of proteasome in physiological and pathological processes, mostly cancer and neurodegenerative diseases, connecting biochemical features and clinical studies of proteasome targeting drugs.

Drug Repurposing Screen Identifies Novel Classes of Drugs with Anticancer Activity in Mantle Cell Lymphoma

AIM AND OBJECTIVE

Mantle Cell Lymphoma (MCL) is typically an aggressive and rare disease with poor prognosis, therefore new effective therapeutics are urgently needed. Drug repurposing for cancer treatment is becoming increasingly more attractive as an alternative approach to discover clinically approved drugs that demonstrate antineoplastic effect. The objective of this study was to screen an approved drug library and identify candidate compounds with an antineoplastic effect in MCL cells using High-Throughput Screening (HTS) technique.

MATERIALS AND METHODS

Using the HTS technique, nearly 3,800 clinically approved drugs and drug candidates were screened in Jeko and Mino MCL cell lines. We also demonstrated the selectivity window of the candidate compounds in six normal cell lines. Further validations were performed in caspase-3/7 apoptosis assay and three-dimensional (3D) multicellular aggregates model using Z138 cell line.

RESULTS

We identified 98 compounds showing >50% inhibition in either MCL cell line screened, they were distributed across eight unique therapeutic categories and have different mechanisms of action (MOA). We selected alisertib, carfilzomib, pracinostat and YM155 for further validation based on their antiproliferative activity in two MCL cell lines, selectivity to normal cell lines, and drug developing stages in terms of clinical research. Alisertib and carfilzomib showed antiproliferative effect on MCL cell with EC50 = 6 nM and >100-fold selectivity to normal cell lines, especially for alisertib which demonstrated >1000-fold selectivity to 5 out of 6 normal cell lines. Pracinostat and YM155 had potency of 11 and 12 nM in MCL cell with >20-fold selectivity to normal cell lines. All four compounds had been tested in caspase-dependent apoptosis assay. We further validated and demonstrated their anti-MCL effect on cell proliferation and (3D) multicellular aggregates model using Z138 cell line.

CONCLUSION

This is the first study to examine such a large library of clinically approved compounds for the identification of novel drug candidates for MCL treatment, the results could be rapidly translated into clinical practice in patients with MCL.

Targeting CD83 in mantle cell lymphoma with anti-human CD83 antibody

Objectives

Effective antibody-drug conjugates (ADCs) provide potent targeted cancer therapies. CD83 is expressed on activated immune cells including B cells and is a therapeutic target for Hodgkin lymphoma. Our objective was to determine CD83 expression on non-Hodgkin lymphoma (NHL) and its therapeutic potential to treat mantle cell lymphoma (MCL) which is currently an incurable NHL.

Methods

We analysed CD83 expression on MCL cell lines and the lymph node/bone marrow biopsies of MCL patients. We tested the killing effect of CD83 ADC in vitro and in an in vivo xenograft MCL mouse model.

Results

CD83 is expressed on MCL, and its upregulation is correlated with the nuclear factor κB (NF-κB) activation. CD83 ADC kills MCL in vitro and in vivo. Doxorubicin and cyclophosphamide (CP), which are included in the current treatment regimen for MCL, enhance the NF-κB activity and increase CD83 expression on MCL cell lines. The combination of CD83 ADC with doxorubicin and CP has synergistic killing effect of MCL.

Conclusion

This study provides evidence that a novel immunotherapeutic agent CD83 ADC, in combination with chemotherapy, has the potential to enhance the efficacy of current treatments for MCL.

Systematic literature review of the global burden of illness of mantle cell lymphoma

Background: Mantle cell lymphoma (MCL), a rare and aggressive disease, accounts for approximately 5% of all B-cell non-Hodgkin's lymphomas. Evidence on the burden of this disease, for patients and healthcare providers, is scarce.Methods: Four systematic literature reviews were developed to identify epidemiological, real-world clinical, economic and humanistic burden data on patients with MCL. Electronic databases searched included MEDLINE and Embase, NHS EED and Econlit.Results: Eight epidemiological studies, 19 clinical burden, 2 economic impact and 0 quality of life studies were identified. The range of standardized MCL incidence rates was 0.1-1.27/100,000. Overall survival rates of patients at 3 years differed by age at diagnosis (≤65 years: 76-81%, >65 years: 46-64%) and disease stage (stage I: 73-80%, stage IV: 48-53%). Outcomes were poorer in previously treated patients, and those with later stage or blastoid disease, and improved with more recent diagnosis/treatment. Hospitalization is a major contributor to healthcare cost and differs by therapy toxicity.Conclusions: We identified significant data gaps for many G20 countries for epidemiology, real-world clinical, economic and humanistic burden. These literature reviews demonstrate the ongoing unmet need for MCL patients globally. Future research to further understand the real-world impact of MCL is needed along with new therapeutic options to improve patient outcomes.

An update on options of therapy for aggressive mantle cell lymphoma

With the emerging application of novel targeted agents in the induction, maintenance and salvage strategies, management of aggressive mantle cell lymphoma is being transformed from high-intensity chemo-immunotherapy applicable to only selected patients, to more personalized treatment incorporating novel agents that are effective and accessible for the majority of the patients. This review summarizes risk-stratified management paradigm for aggressive mantle cell lymphoma, providing context for clinical applications of novel agents and cellular therapy including stem cell transplant and CAR-T.

Long noncoding RNA HAGLROS promotes the process of mantle cell lymphoma by regulating miR-100/ATG5 axis and involving in PI3K/AKT/mTOR signal

This research planned to grab the expression and impact of lncRNA HAGLROS in the biology and progression of mantle cell lymphoma. HAGLROS level in mantle cell lymphoma cell lines was detected, followed by investigation of the influences of HAGLROS silencing on Mino cell biological performances. Afterwards, the express patterns of HAGLROS vs. miR-100, as well as miR-100 vs. ATG5, were investigated. Furthermore, whether HAGLROS could regulate the signals of PI3K/AKT/mTOR was analyzed. HAGLROS level was high in mantle cell lymphoma cell lines. Silencing of HAGLROS inhibited Mino cell viability, increased apoptosis and decreased autophagy by sponging miR-100. Moreover, miR-100 targeted ATG5 fixed. Furthermore, HAGLROS suppression resulted in inhibition on the briskness of PI3K/AKT/mTOR signals. Concurrently HAGLROS suppression and miR-100 inhibitor markedly changed the impacts of HAGLROS down-regulation alone on activating PI3K/AKT/mTOR signals, which could further change after co-transfection of si-HAGLROS + miR-100 inhibitor + siATG5. Our findings point out that expression of HAGLROS is increased in mantle cell lymphoma cells and may function as an oncogene in mantle cell lymphoma. HAGLROS may promote tumour development by regulating miR-100/ATG5/PI3K/AKT/mTOR axis.

Resistance to the Proteasome Inhibitors: Lessons from Multiple Myeloma and Mantle Cell Lymphoma

Since its introduction in the clinics in early 2000s, the proteasome inhibitor bortezomib (BTZ) significantly improved the prognosis of patients with multiple myeloma (MM) and mantle cell lymphoma (MCL), two of the most challenging B cell malignancies in western countries. However, relapses following BTZ therapy are frequent, while primary resistance to this agent remains a major limitation for further development of its therapeutic potential. In the present chapter, we recapitulate the molecular mechanisms associated with intrinsic and acquired resistance to BTZ learning from MM and MCL experience, including mutations of crucial genes and activation of prosurvival signalling pathways inherent to malignant B cells. We also outline the preclinical and clinical evaluations of some potential druggable targets associated to BTZ resistance, considering the most meaningful findings of the past 10 years. Although our understanding of BTZ resistance is far from being completed, recent discoveries are contributing to develop new approaches to treat relapsed MM and MCL patients.

Recent advances in siRNA delivery mediated by lipid-based nanoparticles

Small interfering RNA (siRNA) has been expected to be a unique pharmaceutic for the treatment of broad-spectrum intractable diseases. However, its unfavorable properties such as easy degradation in the blood and negative-charge density are still a formidable barrier for clinical use. For disruption of this barrier, siRNA delivery technology has been significantly advanced in the past two decades. The approval of Patisiran (ONPATTRO™) for the treatment of transthyretin-mediated amyloidosis, the first approved siRNA drug, is a most important milestone. Since lipid-based nanoparticles (LNPs) are used in Patisiran, LNP-based siRNA delivery is now of significant interest for the development of the next siRNA formulation. In this review, we describe the design of LNPs for the improvement of siRNA properties, bioavailability, and pharmacokinetics. Recently, a number of siRNA-encapsulated LNPs were reported for the treatment of intractable diseases such as cancer, viral infection, inflammatory neurological disorder, and genetic diseases. We believe that these contributions address and will promote the development of an effective LNP-based siRNA delivery system and siRNA formulation.

Protein arginine methyltransferase 5 represses tumor suppressor miRNAs that down-regulate CYCLIN D1 and c-MYC expression in aggressive B-cell lymphoma

Protein arginine methyltransferase-5 (PRMT5) is overexpressed in aggressive B-cell non-Hodgkin's lymphomas, including mantle cell lymphoma and diffuse large B-cell lymphoma, and supports constitutive expression of CYCLIN D1 and c-MYC. Here, we combined ChIP analysis with next-generation sequencing to identify microRNA (miRNA) genes that are targeted by PRMT5 in aggressive lymphoma cell lines. We identified enrichment of histone 3 dimethylation at Arg-8 (H3(Me2)R8) in the promoter regions of miR33b, miR96, and miR503. PRMT5 knockdown de-repressed transcription of all three miRNAs, accompanied by loss of recruitment of epigenetic repressor complexes containing PRMT5 and either histone deacetylase 2 (HDAC2) or HDAC3, enhanced binding of co-activator complexes containing p300 or CREB-binding protein (CBP), and increased acetylation of specific histones, including H2BK12, H3K9, H3K14, and H4K8 at the miRNA promoters. Re-expression of individual miRNAs in B-cell lymphoma cells down-regulated expression of PRMT5, CYCLIN D1, and c-MYC, which are all predicted targets of these miRNAs, and reduced lymphoma cell survival. Luciferase reporter assays with WT and mutant 3'UTRs of CYCLIN D1 and c-MYC mRNAs revealed that binding sites for miR33b, miR96, and miR503 are critical for translational regulation of the transcripts of these two genes. Our findings link altered PRMT5 expression to transcriptional silencing of tumor-suppressing miRNAs in lymphoma cells and reinforce PRMT5's relevance for promoting lymphoma cell growth and survival.

Treatment of Older Patients With Mantle Cell Lymphoma (MCL): Long-Term Follow-Up of the Randomized European MCL Elderly Trial

PURPOSE

In an update of the randomized, open-label, phase III European Mantle Cell Lymphoma (MCL) Elderly trial (ClinicalTrials.gov identifier: NCT00209209), published in 2012, we aimed to confirm results on long-term outcome focusing on efficacy and safety of long-term use of rituximab maintenance.

PATIENTS AND METHODS

Five hundred sixty patients with newly diagnosed MCL underwent a first random assignment between rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) and rituximab, fludarabine, and cyclophosphamide (R-FC) induction, followed by a second random assignment in 316 responders between rituximab and interferon alfa maintenance, to be continued until progression. We compared progression-free survival from the second randomization and overall survival (OS) from the first or second randomizations.

RESULTS

After a median follow-up time of 7.6 years, the previously described difference in OS between the induction arms persisted (median, 6.4 years after R-CHOP [n = 280] v 3.9 years after R-FC [n = 280]; P = .0054). Patients responding to R-CHOP had median progression-free survival and OS times of 5.4 and 9.8 years, respectively, when randomly assigned to rituximab (n = 87), compared with 1.9 years (P < .001) and 7.1 years (P = .0026), respectively, when randomly assigned to interferon alfa (n = 97). In 58% and 32% of patients treated with R-CHOP, rituximab maintenance was still ongoing 2 and 5 years from start of maintenance, respectively. After R-FC, rituximab maintenance was associated with an unexpectedly high cumulative incidence of death in remission (22% at 5 years). Toxicity of rituximab maintenance was low after R-CHOP (grade 3-4 leukopenia or infection < 5%) but more prominent in patients on rituximab maintenance after R-FC, in whom grade 3-4 leukopenia (up to 40%) and infections were frequent (up to 15%).

CONCLUSION

The excellent results of R-CHOP followed by rituximab maintenance until progression for older patients with MCL persisted in a mature follow-up. Prolongation of rituximab maintenance beyond 2 years is effective and safe.

Potent efficacy of MCL-1 inhibitor-based therapies in preclinical models of mantle cell lymphoma

Apoptosis-regulating BCL-2 family members, which can promote malignant transformation and resistance to therapy, have become prime therapeutic targets, as illustrated by the striking efficacy in certain lymphoid malignancies of the BCL-2-specific inhibitor venetoclax. In other lymphoid malignancies, however, such as the aggressive mantle cell lymphoma (MCL), cell survival might rely instead or also on BCL-2 relative MCL-1. We have explored MCL-1 as a target for killing MCL cells by both genetic and pharmacologic approaches. In several MCL cell lines, MCL-1 knockout with an inducible CRISPR/Cas9 system triggered spontaneous apoptosis. Accordingly, most MCL cell lines proved sensitive to the specific MCL-1 inhibitor S63845, and MCL-1 inhibition also proved efficacious in an MCL xenograft model. Furthermore, its killing efficacy rose on combination with venetoclax, the BCL-X_L-specific inhibitor A-1331852, or Bruton's tyrosine kinase (BTK) inhibitor ibrutinib, which reduced pro-survival signals. We also tested the MCL-1 inhibitor in primary samples from 13 MCL patients, using CD40L-expressing feeder cells to model their microenvironmental support. Notably, all unstimulated primary MCL samples were very sensitive to S63845, but the CD40L stimulation attenuated their sensitivity. Mass cytometric analysis revealed that the stimulation likely conveyed protection by elevating BCL-X_L and MCL-1. Accordingly, sensitivity of the CD40L-stimulated cells to S63845 was substantially restored by co-treatment with venetoclax, the BCL-X_L-specific inhibitor or ibrutinib. Overall, our findings indicate that MCL-1 is very important for survival of MCL cells and that the MCL-1 inhibitor, both alone and together with ibrutinib, venetoclax or a BCL-X_L inhibitor, offers promise for novel improved MCL therapies.

Combining Ibrutinib with Chk1 Inhibitors Synergistically Targets Mantle Cell Lymphoma Cell Lines

BACKGROUND

Mantle cell lymphoma (MCL) is an aggressive B cell lymphoma with an unfavorable clinical course. Besides deregulation of the cell cycle, B cell receptor (BCR) signaling, essential for MCL proliferation and survival, is also often deregulated due to constitutive activation of Bruton's tyrosine kinase (BTK). The BTK inhibitor ibrutinib has been approved as a therapy for refractory MCL, and while it shows some clinical activity, patients frequently develop primary or secondary ibrutinib resistance and have very poor outcomes after relapsing following ibrutinib treatment.

OBJECTIVE

To overcome ibrutinib resistance, new therapeutic approaches are needed. As checkpoint kinase 1 (Chk1) inhibitors have recently been shown to be effective as single agents in MCL, we assessed the combination of ibrutinib with Chk1 inhibitors.

METHODS

We examined the activity of ibrutinib combined with the Chk1 inhibitor PF-00477736 in eight MCL cell lines and analyzed underlying cellular and molecular effects.

RESULTS

The combination was synergistic in all tested cell lines through different mechanisms. The treatment induced apoptosis in ibrutinib-sensitive cell lines, while in ibrutinib-resistant cells the effect was mainly cytostatic and occurred at micromolar concentrations of ibrutinib.

CONCLUSIONS

The pharmacological approach of simultaneously targeting cell cycle checkpoints (by Chk1 inhibitors) and pro-survival pathways (by ibrutinib) might offer a promising new therapeutic strategy for MCL patients.

Classification of aggressive and classic mantle cell lymphomas using synchrotron Fourier Transform Infrared microspectroscopy

Mantle cell lymphoma (MCL) is regarded as an incurable neoplasm, even to the novel drug strategies. It is known MCL has two morphological variants- classic and aggressive. Aggressive MCL is characterized by a higher mitotic index and proliferation rate, and poor overall survival in comparison to classic subtype. The insight into the detailed biochemical composition of MCL is crucial in the further development of diagnostic and treatment guidelines for MCL patients; therefore Synchrotron radiation Fourier Transform Infrared (S-FTIR) microspectroscopy combined with Principal Component Analysis (PCA) was used. The major spectral differences were observed in proteins and nucleic acids content, revealing a classification scheme of classic and aggressive MCLs. The results obtained suggest that FTIR microspectroscopy has reflected the histopathological discrimination of both MCL subtypes.

Daratumumab displays in vitro and in vivo anti-tumor activity in models of B-cell non-Hodgkin lymphoma and improves responses to standard chemo-immunotherapy regimens

CD38 is expressed in several types of non-Hodgkin lymphoma (NHL) and constitutes a promising target for antibody-based therapy. Daratumumab (Darzalex) is a first-in-class anti-CD38 antibody approved for the treatment of relapsed/refractory (R/R) multiple myeloma (MM). It has also demonstrated clinical activity in Waldenström macroglobulinaemia and amyloidosis. Here, we have evaluated the activity and mechanism of action of daratumumab in preclinical in vitro and in vivo models of mantle cell lymphoma (MCL), follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL), as monotherapy or in combination with standard chemo-immunotherapy. In vitro, daratumumab engages Fc-mediated cytotoxicity by antibody-dependent cell cytotoxicity and antibody-dependent cell phagocytosis in all lymphoma subtypes. In the presence of human serum, complement-dependent cell cytotoxicity was marginally engaged. We demonstrated by Selective Plane Illumination Microscopy that daratumumab fully penetrated a three-dimensional (3D) lymphoma organoid and decreased organoid volume. In vivo, daratumumab completely prevents tumor outgrowth in models of MCL and FL, and shows comparable activity to rituximab in a disseminated in vivo model of blastic MCL. Moreover, daratumumab improves overall survival (OS) in a mouse model of transformed CD20^dim FL, where rituximab showed limited activity. Daratumumab potentiates the antitumor activity of CHOP and R-CHOP in MCL and FL xenografts. Furthermore, in a patient-derived DLBCL xenograft model, daratumumab anti-tumor activity was comparable to R-CHOP and the addition of daratumumab to either CHOP or R-CHOP led to full tumor regression. In summary, daratumumab constitutes a novel therapeutic opportunity in certain scenarios and these results warrant further clinical development.

Development of a clinically relevant chemoresistant mantle cell lymphoma cell culture model

Mantle cell lymphoma is an aggressive subtype of non-Hodgkin’s lymphoma that claims the lives of tens of thousands of people every year. Although combination chemotherapy treatments such as CHOP have yielded promising outcomes in the clinic, the development of chemoresistance in patients has limited their long-term success. The lack of in vitro chemoresistance models has limited our ability to understand the mechanisms by which cells develop resistance, and thus our ability to develop novel therapeutics to overcome this issue. Here, we describe the development of a clinically relevant chemoresistant mantle cell lymphoma model using the JeKo-1 cell line. This was achieved through a stepwise treatment selection strategy using gradually increasing concentrations of CHOP. We show that resistant JeKo-1 cells display strong recovery and fast proliferation after treatment with an IC50 dose of CHOP. We also found that resistant JeKo-1 cells overexpress three oncogenes implicated in the development of mantle cell lymphoma—Cyclin D1, Mcl-1, and Bcl-2—compared to normal JeKo-1 cells. We anticipate that in vitro models such as this one will enable the discovery of new therapeutic strategies for overcoming chemoresistance and improve clinical outcomes in mantle cell lymphoma patients.

Impact statement

Mantle cell lymphoma remains one of the deadliest subtypes of non-Hodgkin’s lymphoma, in large part because patients become resistant to frontline chemotherapy. The development of strategies to treat advanced disease will be contingent upon testing in appropriate models. Most in vitro models of resistant mantle cell lymphoma are laboratory grade models that do not recapitulate the low level of chemoresistance typically observed in patients, limiting their utility. This study develops a clinically relevant in vitro model that can be used to establish the mechanisms of resistance and test new therapeutics intended to treat recurrent disease.

DNA Damage Response Inhibitor Combinations Exert Synergistic Antitumor Activity in Aggressive B-Cell Lymphomas

The DNA damage response (DDR) kinases ATR, Chk1, and Wee1 play vital roles in the response to replication stress and in maintaining cancer genomic stability. Inhibitors of these kinases are currently under clinical investigation. Mantle cell lymphoma (MCL) and diffuse large B-cell lymphoma (DLBCL) are aggressive lymphomas whose clinical outcome is still largely unsatisfactory. These cell lymphoma subtypes are highly dependent on both Chk1 and Wee1 for survival. We investigated the activity of the ATR inhibitor AZD6738 as single agent and in combination with either Chk1 (AZD6738) or Wee1 (AZD1775) inhibitors in several preclinical models of MCL and DLBCL. This study included preclinical in vitro activity screening on a large panel of cell lines, both as single agent and in combination, and validation experiments on in vivo models. Cellular and molecular mechanisms of the observed synergistic effect as well as pharmacodynamic analysis of in vivo samples were studied. AZD6738 exerted a strong synergistic cytotoxic effect in combination with both AZD7762 and AZD1775 in the 2 lymphoma subtypes regardless of their TP53, MYC, and ATM mutational status. These DDR inhibitor combinations, similarly to the Chk1/Wee1 inhibitor combination, caused a marked S-phase delay, with an increase in cyclin-dependent kinases (CDK) activity, increased DNA damage, and decreases in Wee1, MYC, and RRM2 protein levels. The synergistic in vitro activity translated to striking in vivo antitumor activity. DDR-DDR inhibitor combinations could potentially offer promising novel therapeutic strategies for patients with B-cell lymphoma.

A high mutation rate of immunoglobulin heavy chain variable region gene associates with a poor survival and chemotherapy response of mantle cell lymphoma patients

Immunoglobulin heavy chain variable region (IGHV) gene mutation status is a biomarker for the prognosis of chronic lymphocytic leukemia, whether it is associated with the diagnosis, staging, and prognosis of patients with mantle cell lymphoma (MCL) remains to be determined.The IGHV gene mutations of 52 MCL patients were determined by DNA sequencing and compared with published IGHV germline sequences.DNA sequence alignment of IGHV variable regions with published IGHV germline sequences showed that the coincidence rate was 94% to 100%. Ten cases (21%) were significantly mutated with the rate of 96.9% to 94.0%. The overall survival time of patients was negatively correlated with the degree of IGHV gene mutation. Further survival analysis with log-rank test demonstrated that the patients with significant IGHV gene mutations showed a trend towards poor survival.The mutation rate of the IGHV variant region may be determined to assess the prognosis and overall survival time of MCL patients.

Bilateral mantle cell lymphoma of the ciliary body that responded to a combined local radiotherapy and chemotherapy regimen: a case report

BACKGROUND

Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) that often affects men over the age of 60. Systemic metastasis of MCL to eyes is rare and intraocular involvement is even rarer, which usually affects the choroid and iris. To the best of our knowledge, ciliary body metastasis of systemic MCL has not been reported.

CASE PRESENTATION

A 59-year-old Han Chinese male with past-history of systemic MCL complained of redness, pain and blurred vision in the left eye. Ocular examination revealed a normal appearance in the right eye, and conjunctival injection, pseudohypopyon and anterior protrusion of peripheral iris in the left eye, all of which were unresponsive to corticosteroid treatments. Ultrasound biomicroscopy (UBM) and B-scan were then performed which detected ciliary body masses in both eyes with no vitreous and retino-choroidal anomalies. Combined liquid-based cytology tests and gene rearrangement assays of the aqueous humor specimen confirmed this to be a B-cell malignancy. Then both eyes were treated with external beam irradiation (40 Gy, delivered evenly in twenty fractions) over a course of one month. Additionally, the left eye received intravitreal methotrexate (MTX) (weekly for the first month, every two weeks for the second month, and monthly thereafter) over a course of twelve months. This therapy eventually led to complete remission of all symptoms in one month and disappearance of the ciliary body masses in twelve months.

CONCLUSION

Here we first reported a case of bilateral ciliary body MCL infiltration which was diagnosed by combined liguid-based cytology and gene rearrangement of aqueous humor cells. UBM may serve as a valuable tool in the diagnosis and serial assessments of anterior segment tumors.

Consolidation with 90Y ibritumomab tiuxetan radioimmunotherapy in mantle cell lymphoma patients ineligible for high dose therapy: results of the phase II multicentre Polish Lymphoma Research Group trial, after 8-year long follow-up

Polish Lymphoma Research Group performed a phase-II trial to test whether ⁹⁰Y ibritumomab tiuxetan radioimmunotherapy (Y90) may constitute an alternative consolidation for mantle cell lymphoma patients unfit for high-dose therapy. Forty-six patients were consolidated with Y90 following response to the 1st (n = 34) or 2nd line (n = 12) (immuno)chemotherapy. Majority of the patients had advanced disease (stage IV and presence of B-symptoms in 85% and 70%, respectively) and high MIPI (5.8, range 4-7). Consolidation with Y90 increased the complete remission (CR) rate obtained by the 1st line therapy from 41% to 91% and allowed for median PFS of 3.3 and OS of 6.5 years. In the first relapse, CR rate increased from 16% to 75%, while median PFS and OS totaled 2.2 and 6.5 years, respectively. At 8 years, 30% of patients, consolidated in the 1st line CR were alive, without relapse. Toxicity associated with Y90 is manageable, more severe after fludarabine-based regimens.