Approach to the diagnosis and treatment of high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements

Targeted inhibition of DHODH is synergistic with BCL2 blockade in HGBCL with concurrent MYC and BCL2 rearrangement

High-grade B-cell lymphoma (HGBCL), the subtype of non-Hodgkin lymphoma, to be relapsed or refractory in patients after initial therapy or salvage chemotherapy. Dual dysregulation of MYC and BCL2 is one of the important pathogenic mechanisms. Thus, combined targeting of MYC and BCL2 appears to be a promising strategy. Dihydroorotate dehydrogenase (DHODH) is the fourth rate-limiting enzyme for the de novo biosynthesis of pyrimidine. It has been shown to be a potential therapeutic target for multiple diseases. In this study, the DHODH inhibitor brequinar exhibited growth inhibition, cell cycle blockade, and apoptosis promotion in HGBCL cell lines with MYC and BCL2 rearrangements. The combination of brequinar and BCL2 inhibitors venetoclax had a synergistic inhibitory effect on the survival of DHL cells through different pathways. Venetoclax could upregulate MCL-1 and MYC expression, which has been reported as a resistance mechanism of BCL2 inhibitors. Brequinar downregulated MCL-1 and MYC, which could potentially overcome drug resistance to venetoclax in HGBCL cells. Furthermore, brequinar could downregulate a broad range of genes, including ribosome biosynthesis genes, which might contribute to its anti-tumor effects. In vivo studies demonstrated synergetic tumor growth inhibition in xenograft models with brequinar and venetoclax combination treatment. These results provide preliminary evidence for the rational combination of DHODH and BCL2 blockade in HGBCL with abnormal MYC and BCL2.

Molecular complexity of diffuse large B-cell lymphoma: a molecular perspective and therapeutic implications

Diffuse large B-cell lymphoma (DLBCL) stands as a formidable challenge in the landscape of non-Hodgkin's lymphomas. This review illuminates the remarkable strides made in comprehending DLBCL's molecular intricacies and devising targeted treatments. DLBCL, the most prevalent non-Hodgkin's lymphoma, has seen transformative progress in its characterization. Genetic investigations, led by high-throughput sequencing, have unveiled recurrent mutations in genes such as MYC, BCL2, and BCL6, casting light on the underlying genetic chaos propelling DLBCL's aggressiveness. A pivotal facet of this understanding centers on cell signaling pathways. Dysregulation of B-cell receptor (BCR) signaling, NF-κB, PI3K/Akt/mTOR, JAK/STAT, Wnt/β-Catenin, and Toll-like receptor pathways plays a critical role in DLBCL pathogenesis, offering potential therapeutic targets. DLBCL's complex tumor microenvironment (TME) cannot be overlooked. The dynamic interplay among tumor cells, immune cells, stromal components, and the extracellular matrix profoundly influences DLBCL's course and response to therapies. Epigenetic modifications, including DNA methylation and histone changes, add another layer of intricacy. Aberrant epigenetic regulation plays a significant role in lymphomagenesis, offering prospects for epigenetic-based therapies. Promisingly, these molecular insights have spurred the development of personalized treatments. Targeted therapies and immunotherapies, guided by genomic profiling and molecular classification, are emerging as game-changers in DLBCL management. In conclusion, this review underscores the remarkable strides in understanding DLBCL's molecular underpinnings, spanning genetics, cell signaling, the tumor microenvironment, and epigenetics. These advances pave the way for more effective, personalized treatments, renewing hope for DLBCL patients.

Efficacy and safety of Orelabrutinib-based regimens in diffuse large B-cell lymphoma: a single-center retrospective analysis

Currently, combining chemotherapy with Bruton tyrosine kinase inhibitors (BTKi) has demonstrated significant effectiveness in treating patients with diffuse large B-cell lymphoma. Orelabrutinib is a second-generation BTK inhibitor, and presently, there have been few reports of Orelabrutinib being used to treat DLBCL. We conducted a retrospective investigation to explore the safety and efficacy of Orelabrutinib in combination with chemotherapy or immunotherapy. The study comprised 19 patients with a median age of 61 years. The overall response rate (ORR) was 89.5% with a complete response (CR) rate of 73.7% and a partial response rate (PR) of 15.8%. The estimated 2-year overall survival (OS) and progression-free survival (PFS) rates were 78.6% (95%CI, 59.8%-100%) and 72.2% (95% CI, 52.4%-99.6%), respectively, with a median follow-up time of 11 months (range 2-24). The most prevalent grade 3 or 4 adverse events (AEs), neutropenia (52.6%), anemia (36.8%), thrombocytopenia (26.3%), febrile neutropenia (26.3%), and lung infection (10.5%), were the most common. Our results reveal that Orelabrutinib is an effective therapy for DLBCL patients. Furthermore, our first investigation of the Orelabrutinib application lays a foundation for larger retrospective studies.

Enitociclib, a Selective CDK9 Inhibitor, Induces Complete Regression of MYC+ Lymphoma by Downregulation of RNA Polymerase II Mediated Transcription

Double-hit diffuse large B-cell lymphoma (DH-DLBCL) is an aggressive, and often refractory, type of B-cell non-Hodgkin lymphoma (NHL) characterized by rearrangements in MYC and BCL2. Cyclin-dependent kinase 9 (CDK9) regulates transcriptional elongation and activation of transcription factors, including MYC, making it a potential targeted approach for the treatment of MYC+ lymphomas. Enitociclib is a well-tolerated and clinically active CDK9 inhibitor leading to complete metabolic remissions in 2 of 7 patients with DH-DLBCL treated with once weekly 30 mg intravenous administration. Herein, we investigate the pharmacodynamic effect of CDK9 inhibition in preclinical models and in blood samples from patients [DH-DLBCL (n = 10) and MYC+ NHL (n = 5)] treated with 30 mg i.v. once weekly enitociclib. Enitociclib shows significant regulation of RNA polymerase II Ser2 phosphorylation in a MYC-amplified SU-DHL-4 cell line and depletion of MYC and antiapoptosis protein MCL1 in SU-DHL-4 and MYC-overexpressing SU-DHL-10 cell lines in vitro. Tumor growth inhibition reaching 0.5% of control treated SU-DHL-10 xenografts is achieved in vivo and MYC and MCL1 depletion as well as evidence of apoptosis activation after enitociclib treatment is demonstrated. An unbiased analysis of the genes affected by CDK9 inhibition in both cell lines demonstrates that RNA polymerase II and transcription pathways are primarily affected and novel enitociclib targets such as PHF23 and TP53RK are discovered. These findings are recapitulated in blood samples from enitociclib-treated patients; while MYC downregulation is most robust with enitociclib treatment, other CDK9-regulated targets may be MYC independent delivering a transcriptional downregulation via RNA polymerase II.

SIGNIFICANCE

MYC+ lymphomas are refractory to standard of care and novel treatments that downregulate MYC are needed. The utility of enitociclib, a selective CDK9 inhibitor in this patient population, is demonstrated in preclinical models and patients. Enitociclib inhibits RNA polymerase II function conferring a transcriptional shift and depletion of MYC and MCL1. Enitociclib intermittent dosing downregulates transcription factors including MYC, providing a therapeutic window for durable responses in patients with MYC+ lymphoma.

The synergy of the XPO1 inhibitors combined with the BET inhibitor INCB057643 in high-grade B-cell lymphoma via downregulation of MYC expression

High grade B-cell lymphoma with MYC and BCL2 rearrangements (HGBCL-DH) represents an uncommon B-cell lymphoma (BCL) with aggressive clinical courses and poor prognosis. Despite revolutionary therapeutic advances in BCL, there has been limited treatment progress in HGBCL-DH, thus necessitating additional therapeutic strategies for HGBCL-DH. This study demonstrated that the BET antagonist INCB057643 synergized with the XPO1 inhibitors (selinexor and eltanexor) to decrease cell viability and increase cell apoptosis in HGBCL-DH cells with or without TP53 mutations. As anticipated, the combined treatment of INCB057643 with selinexor slowed tumor growth and reduced the tumor burden in TP53-mutated HGBCL-DH xenografts. Mechanistically, MYC functional inhibition was a potential molecular mechanism underlying the synergy of the combined INCB057643 and selinexor treatment in HGBCL-DH cells independent of TP53 mutation status. In TP53 mutated HGBCL-DH cells, inducing DNA damage and impairing the DNA damage response (DDR) were involved in the therapeutic interaction of the combined regimen. In TP53 wild-type cells, the molecular mechanism was linked with upregulation of p53 levels and activation of its targeted pathways, rather than dysregulation of the DDR. Collectively, we might provide a potential promising combination therapy regimen for the management of HGBCL-DH. Clinical evaluations are warranted to confirm this conclusion.

Targeting MYC-driven lymphoma: lessons learned and future directions

MYC plays a central role in tumorigenesis by orchestrating cell proliferation, growth and survival, among other transformation mechanisms. In particular, MYC has often been associated with lymphomagenesis. In fact, MYC overexpressing lymphomas such as high-grade B-cell lymphoma (HGBL) and double expressor diffuse large B-cell lymphomas (DLBCL), are considered addicted to MYC. In such a context, MYC targeting therapies are of special interest, as MYC withdrawal is expected to result in tumor regression. However, whether high MYC levels are always predictive of increased sensitivity to these approaches is not clear yet. Even though no MYC inhibitor has received regulatory approval to date, substantial efforts have been made to investigate avenues to render MYC a druggable target. Here, we summarize the different classes of molecules currently under development, which mostly target MYC indirectly in aggressive B-cell lymphomas, paying special attention to subtypes with MYC/BCL2 or BCL6 translocations or overexpression.

Genetic Profiling of Diffuse Large B-Cell Lymphoma: A Comparison Between Double-Expressor Lymphoma and Non-Double-Expressor Lymphoma

INTRODUCTION

Data are limited regarding the genetic profiling of diffuse large B-cell lymphoma (DLBCL) with double expression of MYC and BCL2 proteins without underlying rearrangements (double-expressor lymphoma [DEL]). This study aimed to describe the genetic profiling and determine the prognostic significance in patients with DEL and in those with non-DEL.

METHODS

Capture-based targeted sequencing was performed on 244 patients with de novo DLBCL, not otherwise specified. Immunohistochemistry staining was performed for evaluating the MYC and BCL2 expression.

RESULTS

Among 244 patients, 46 patients had DEL, and 198 had non-DEL. KMT2D, CD58, EP300, PRDM1, TNFAIP3 and BCL2 gain or amplification (BCL2^GA/AMP) were significantly more frequently altered in the DEL group. Alterations in the BCR/TLR (p = 0.021), B-cell development and differentiation (p = 0.004), and NF-κB (p = 0.034) pathways occurred more frequently in patients with DEL. Thirty-seven DEL patients and 132 non-DEL patients were included for survival analyses. DEL was not significantly associated with progression-free survival (PFS) (p = 0.60) and overall survival (OS) (p = 0.49). In DEL patients, after adjusting for the International Prognostic Index, BCL2 alteration (HR 2.516, 95% CI 1.027-6.161; p = 0.044) remained an independent predictor of inferior PFS. BCL2^GA/AMP also predicted poor PFS, but with marginal statistical significance (HR 2.489, 95% CI 0.995-6.224; p = 0.051).

CONCLUSION

There was difference in profiling of altered genes and signaling pathways between the DEL group and the non-DEL group. The presence of DEL alone should not be considered as an adverse prognostic indicator, and BCL2 alteration could define a subset of patients with poor prognosis within DEL.

Expression of TCF3 target genes defines a subclass of diffuse large B-cell lymphoma characterized by up-regulation of MYC target genes and poor clinical outcome following R-CHOP therapy

TCF3 is a lymphopoietic transcription factor that acquires somatic driver mutations in diffuse large B-cell lymphoma (DLBCL). Hypothesizing that expression patterns of TCF3-regulated genes can inform clinical management, we found that unsupervised clustering analysis with 15 TCF3-regulated genes and eight additional ones resolved local DLBCL cases into two main clusters, denoted Groups A and B, of which Group A manifested inferior overall survival (OS, p = 0.0005). We trained a machine learning model to classify samples into the Groups based on expression of the 23 transcripts in an independent validation cohort of 569 R-CHOP-treated DLBCL cases. Group A overlapped with the ABC cell-of-origin subgroup but its prognostic power was superior. GSEA analysis demonstrated asymmetric expression of 30 gene sets between the Groups, pointing to biological differences. We present, validate and make available a novel method to assign DLBCL cases into biologically-distinct groups with divergent OS following R-CHOP therapy.

High-intensity chemotherapy improved the prognosis of patients with high-grade B-cell lymphoma

Objective

High-grade B-cell lymphoma (HGBL) is highly aggressive and has a poor prognosis.

Methods

The clinical data of 76 patients with High-grade B-cell lymphoma treated in our lymphoma center from July 2016 to April 2020 were analyzed retrospectively. The clinical features, treatment and prognosis of patients with two types of high-grade B-cell lymphoma were compared and analyzed.

Results

Among 76 patients with high-grade B-cell lymphoma, 44 cases (57.9%) were high-grade B-cell lymphoma, accompanied by MYC and Bcl-2 and/or Bcl-6 rearrangement (HGBLR) patients, and 32 cases (42.1%) were HGBL, NOS patients. The bone marrow infiltration, IPI (international prognostic index), Ann Arbor stage (III/IV), extranodal disease are more likely to occur in HGBLR group (P <0.05). Survival analysis of patients showed that overall survival (OS) and progression free survival (PFS) in HGBLR group were significantly shorter than those in HGBL, NOS group (median OS: 21 months vs not reached, P=0. 022; median PFS: 5 months vs 12 months, P = 0. 001). Further analysis demonstrated that, as compared with R-CHOP regimen, patients with HGBL who received high-intensity chemotherapy regimens (DA-EPOCH-R, R-CODOX-M/IVAC and R-Hyper-CVAD) had longer OS (median OS, 16 months vs not reached, P=0. 007) and PFS (median PFS, 5 months vs 11 months, P<0.001). Moreover, mu1tivariate ana1ysis showed that high-intensity chemotherapy regimens were independent risk factors for both PFS (P =0.001, HR: 0.306, 95% CI: 0.153-0.610) and OS (P =0.004, HR: 0.262, 95% CI: 0.105-0.656) in patients with HGBL.

Conclusions

HGBLR patients have worse prognosis than patients with HGBL, NOS. High-intensity chemotherapy may improve the prognosis of patients with HGBL.

Genetic and phenotypic characterisation of HIV-associated aggressive B-cell non-Hodgkin lymphomas, which do not occur specifically in this population: diagnostic and prognostic implications

The frequency of aggressive subtypes of B-cell non-Hodgkin lymphoma (B-NHL), such as high-grade B-cell lymphomas (HGBL) with MYC and BCL2 and/or BCL6 rearrangement (HGBL-DH/TH) or Burkitt-like lymphoma (BL) with 11q aberration, is not well known in the HIV setting. We aimed to characterise HIV-associated aggressive B-NHL according to the 2017 WHO criteria, and to identify genotypic and phenotypic features with prognostic impact. Seventy-five HIV-associated aggressive B-NHL were studied by immunohistochemistry (CD10, BCL2, BCL6, MUM1, MYC, and CD30), EBV-encoded RNAs (EBERs), and fluorescence in situ hybridisation (FISH) to evaluate the status of the MYC, BCL2, and BCL6 genes and chromosome 11q. The 2017 WHO classification criteria and the Hans algorithm, for the cell-of-origin classification of diffuse large B-cell lymphomas (DLBCL), were applied. In DLBCL cases, the frequencies of MYC and BCL6 rearrangements (14.9 and 27.7%, respectively) were similar to those described in HIV-negative patients, but BCL2 rearrangements were infrequent (4.3%). MYC expression was identified in 23.4% of DLBCL cases, and coexpression of MYC and BCL2 in 13.0%, which was associated with a worse prognosis. As for BL cases, the expression of MUM1 (30.4%) conferred a worse prognosis. Finally, the prevalence of HGBL-DH/TH and BL-like with 11q aberration are reported in the HIV setting. The phenotypic and genotypic characteristics of HIV-associated aggressive B-NHL are similar to those of the general population, except for the low frequency of BCL2 rearrangements in DLBCL. MYC and BCL2 coexpression in DLBCL, and MUM-1 expression in BL, have a negative prognostic impact on HIV-infected individuals.

Evidence-based review of genomic aberrations in diffuse large B cell lymphoma, not otherwise specified (DLBCL, NOS): Report from the cancer genomics consortium lymphoma working group

Diffuse large B cell lymphoma, not otherwise specified (DLBCL, NOS) is the most common type of non-Hodgkin lymphoma (NHL). The 2016 World Health Organization (WHO) classification defined DLBCL, NOS and its subtypes based on clinical findings, morphology, immunophenotype, and genetics. However, even within the WHO subtypes, it is clear that additional clinical and genetic heterogeneity exists. Significant efforts have been focused on utilizing advanced genomic technologies to further subclassify DLBCL, NOS into clinically relevant subtypes. These efforts have led to the implementation of novel algorithms to support optimal risk-oriented therapy and improvement in the overall survival of DLBCL patients. We gathered an international group of experts to review the current literature on DLBCL, NOS, with respect to genomic aberrations and the role they may play in the diagnosis, prognosis and therapeutic decisions. We comprehensively surveyed clinical laboratory directors/professionals about their genetic testing practices for DLBCL, NOS. The survey results indicated that a variety of diagnostic approaches were being utilized and that there was an overwhelming interest in further standardization of routine genetic testing along with the incorporation of new genetic testing modalities to help guide a precision medicine approach. Additionally, we present a comprehensive literature summary on the most clinically relevant genomic aberrations in DLBCL, NOS. Based upon the survey results and literature review, we propose a standardized, tiered testing approach which will help laboratories optimize genomic testing in order to provide the maximum information to guide patient care.

Decreased CD11c-positive dendritic cells in the tumor microenvironment predict double-hit/triple-hit genotype and survival in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma and is a potentially curable disease. However, it is heterogenous, and the prognosis is poor if the tumor cells harbor fusions involving MYC and BCL2 or MYC and BCL6 (double-hit [DH] lymphoma), or fusions involving all three genes (triple-hit [TH] lymphoma). Fluorescence in situ hybridization is currently the gold standard for confirming the presence of DH/TH genotypes. However, the test is laborious and not readily available in some laboratories. Germinal center B (GCB) signatures and dual expression of MYC and BCL2 are commonly used as initial screening markers (traditional model) in clinical practice. Our study proposes immunohistochemical markers for more conveniently and accessibly screening DH/TH genotypes in DLBCL. We retrospectively reviewed the clinical and pathological parameters of patients with DLBCL. We assessed the proliferative index, apoptotic index, and tumor microenvironment (TME), with regard to T cells and CD11c(+) dendritic cells, in formalin-fixed paraffin-embedded tissue. We then generated a decision tree as a screening algorithm to predict DH/TH genotypes and employed decision curve analysis to demonstrate the superiority of this new model in prediction. We also assessed the prognostic significance of related parameters. Our study revealed that GCB subtypes, a Ki67 proliferative index higher than 70%, and BCL2 expression were significantly associated with DH/TH genotypes. Decreased CD11c(+) dendritic cells in the TME indicated additional risk. Our proposed screening algorithm outperformed a traditional model in screening for the DH/TH genotypes. In addition, decreased CD11c(+) dendritic cells in the DLBCL TME were an independent unfavorable prognosticator. In conclusion, we provide a convenient, well-performing model that predicts DH/TH genotypes in DLBCL. The prognostic significance of CD11c(+) dendritic cells in the TME might influence the classification and development of immunotherapy for DLBCL in the future.

A Combined Biomarker of Bright CD38 and MYC ≥55% Is Highly Predictive of Double-/Triple-Hit High-Grade B-Cell Lymphoma

OBJECTIVES

Diagnosis of high-grade B-cell lymphoma with MYC and BCL2 or BCL6 rearrangements (double-/triple-hit lymphoma [DTHL]) appears to mandate fluorescence in situ hybridization (FISH) testing for all large B-cell lymphoma (LBCL). Given the low incidence of DTHL, we aimed to identify flow cytometry (FC) and immunohistochemistry (IHC) features of DTHL that could be used to develop an optimal screening strategy. This combined FC-IHC approach has not yet been studied.

METHODS

We compared features of 40 cases of DTHL and 39 cases of diffuse LBCL (DLBCL) without MYC rearrangement.

RESULTS

Bright CD38 expression (CD38bright) by FC, high MYC expression (≥55%), and double-expressor phenotype by IHC were significantly associated with DTHL. The biomarker combining FC and IHC, CD38bright and/or MYC ≥55%, was superior to FC and IHC markers alone in predicting DTHL. Restricting FISH testing to approximately 25% of LBCL based on CD38brightand/or MYC ≥55% would detect approximately 95% of DTHL-BCL2 and approximately 75% of DHL-BCL6.

CONCLUSIONS

Our study demonstrated that the novel biomarker of CD38bright and/or MYC ≥55% is highly predictive of DTHL. Awareness of the advantages and limitations of this screening strategy would facilitate development of a rational diagnostic workflow to provide high-quality patient care.

Ideal dose intensity of R-CHOP in diffuse large B-cell lymphoma

INTRODUCTION

The standard of care for diffuse large B-cell lymphoma (DLBCL) is rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). However, its ideal dose intensity varies among cases.

AREAS COVERED

This review provides the latest insights on the dose intensity of R-CHOP for DLBCL patients. Specifically, we discussed the optimal dose intensity for elderly patients, the optimal number of treatment cycles for limited or advanced-stage diseases, and the role of dose-intensified therapies or adding targeted inhibitors.

EXPERT OPINION

Performing a comprehensive or simplified geriatric assessment can distinguish elderly DLBCL patients who will likely benefit from curative R-CHOP. Very elderly or medically unfit patients may need dose reduction in R-CHOP; the Age, Comorbidities, and Albumin index may aid decision-making. Four cycles of R-CHOP followed by two rituximab cycles comprise a new standard for low-risk, limited-stage DLBCL patients. Compared to eight cycles, six cycles of R-CHOP have similar efficacy and fewer toxicities for advanced-stage DLBCL. Dose-intensified therapy is not recommended in most DLBCL cases but may be considered for patients with double (or triple)-hit lymphoma. Applying targeted inhibitors and not merely escalating R-CHOP dose intensity through molecular subtyping will improve the treatment outcome for DLBCL.

Altered pathways and targeted therapy in double hit lymphoma

High-grade B-cell lymphoma with translocations involving MYC and BCL2 or BCL6, usually referred to as double hit lymphoma (DHL), is an aggressive hematological malignance with distinct genetic features and poor clinical prognosis. Current standard chemoimmunotherapy fails to confer satisfying outcomes and few targeted therapeutics are available for the treatment against DHL. Recently, the delineating of the genetic landscape in tumors has provided insight into both biology and targeted therapies. Therefore, it is essential to understand the altered signaling pathways of DHL to develop treatment strategies with better clinical benefits. Herein, we summarized the genetic alterations in the two DHL subtypes (DHL-BCL2 and DHL-BCL6). We further elucidate their implications on cellular processes, including anti-apoptosis, epigenetic regulations, B-cell receptor signaling, and immune escape. Ongoing and potential therapeutic strategies and targeted drugs steered by these alterations were reviewed accordingly. Based on these findings, we also discuss the therapeutic vulnerabilities that coincide with these genetic changes. We believe that the understanding of the DHL studies will provide insight into this disease and capacitate the finding of more effective treatment strategies.

Targeting Cellular Iron Homeostasis with Ironomycin in Diffuse Large B-cell Lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common hematological malignancy. Although more than half of patients with DLBCL achieve long-term remission, the majority of remaining patients succumb to the disease. As abnormal iron homeostasis is implicated in carcinogenesis and the progression of many tumors, we searched for alterations in iron metabolism in DLBCL that could be exploited to develop novel therapeutic strategies. Analysis of the iron metabolism gene expression profile of large cohorts of patients with DLBCL established the iron score (IS), a gene expression-based risk score enabling identification of patients with DLBCL with a poor outcome who might benefit from a suitable targeted therapy. In a panel of 16 DLBCL cell lines, ironomycin, a promising lysosomal iron-targeting small molecule, inhibited DLBCL cell proliferation at nanomolar concentrations compared with typical iron chelators. Ironomycin also induced significant cell growth inhibition, ferroptosis, and autophagy. Ironomycin treatment resulted in accumulation of DNA double-strand breaks, delayed progression of replication forks, and increased RPA2 phosphorylation, a marker of replication stress. Ironomycin significantly reduced the median number of viable primary DLBCL cells of patients without major toxicity for nontumor cells from the microenvironment and presented low toxicity in hematopoietic progenitors compared with conventional treatments. Significant synergistic effects were also observed by combining ironomycin with doxorubicin, BH3 mimetics, BTK inhibitors, or Syk inhibitors. Altogether, these data demonstrate that a subgroup of high-risk patients with DLBCL can be identified with the IS that can potentially benefit from targeting iron homeostasis.

SIGNIFICANCE

Iron homeostasis represents a potential therapeutic target for high-risk patients with DLBCL that can be targeted with ironomycin to induce cell death and to sensitize tumor cells to conventional treatments.

ZCL-082, a boron-containing compound, induces apoptosis of non-Hodgkin's lymphoma via targeting p90 ribosomal S6 kinase 1/NF-κB signaling pathway

INTRODUCTION

Despite the rapid progress in the diagnosis and treatment, the prognosis of some types of non-Hodgkin's lymphoma (NHL), especially those with double-hit or double-expressor genotypes, remains poor. Novel targets and compounds are needed to improve the prognosis of NHL.

METHODS

We investigated the effect of ZCL-082, a novel boron-containing compound with anti-proliferating activity against ovarian cancer cells, on NHL cells and human peripheral blood mononuclear cells by CCK-8 assay, Annexin V/PI double staining assay, RH123/PI double staining, Western blot, and immunohistochemistry. NF-κB pathway activity was analyzed using luciferase reporter gene assay and RT-PCR. The location of p65 was detected by immunofluorescence and nuclear/cytoplasmic fractionation assay. Immunoprecipitation and chromatin immunoprecipitation assays were used to detect the binding between p65 and p300. CETSA and molecular docking assay were carried out to test the interaction between ZCL-082 and p90 ribosomal S6 kinase 1 (RSK1). Kinase reaction was conducted to examine the inhibition of RSK1 kinase activity by ZCL-082.

RESULTS

We found that ZCL-082 can induce the apoptosis of various NHL cell lines in vitro and in vivo. ZCL-082 significantly inhibits TNFα- or LPS-induced NF-κB activation without disturbing TNFα-induced IκBα degradation or the nuclear translocation and DNA-binding ability of p65. However, ZCL-082 markedly suppresses the phosphorylation of p65 on Ser536 and the interaction between p65 and p300. The overexpression of the phosphomimetic mutant of p65 at Ser536 partially abrogates ZCL-082-induced cell death. We further found that ZCL-082 directly binds to and inhibits the activity of RSK1. RSK1 can phosphorylate RelA/p65 on Ser536 and its overexpression is associated with the poor prognosis of lymphoma. The overexpression of RSK1 partially rescues ZCL-082-induced cell death. Molecular docking studies show that ZCL-082 fits well with the N-terminal kinase domain of RSK1. Furthermore, the combination of ZCL-082 and BCL-2 inhibitor ABT-199 has a synergistic apoptosis-inducing effect against double-hit lymphoma cell line OCI-Ly10.

DISCUSSION

We found that ZCL-082 is a highly promising anti-lymphoma compound that targets RSK1 and interferes with the RSK1/NF-κB signaling pathway. The combination of ZCL-082 with BCL-2 inhibitor may represent a novel strategy to improve the outcome of double-hit or double-expressor lymphoma.

Primary breast double-hit lymphoma management and outcomes: a real-world multicentre experience

Background

Primary breast double-hit lymphoma (PB-DHL) is a rare, highly aggressive malignancy that poses challenges regarding accurate diagnosis and selecting optimal treatment regimens.

Methods

We retrospectively reviewed 48 cases of patients diagnosed with PB-DHL in six academic centres between June 2014 and June 2020 in China. Study-specific data were recorded, including treatment options, therapeutic evaluation, prognostic factors and relapse patterns, and the overall survival (OS) and progression-free survival (PFS) were evaluated.

Results

In total, 48 patients were enrolled, with 14 patients treated with DA-EPOCH-R/MA (rituximab, dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, alternating with high-dose methotrexate and cytarabine), 18 patients treated with DA-EPOCH-R (rituximab, dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin), and 16 patients treated with R-HyperCVAD (rituximab, hyperfractionated cyclophosphamide, vincristine, doxorubicin, dexamethasone, alternating with cytarabine plus methotrexate). The overall 5-year OS and PFS rates were 41.7% (95% confidence interval [CI], 27.6–56.8%) and 37.5% (95% CI, 24.0–52.6%), respectively. Of the three treatment regimens, the 5-year OS was higher in DA-EPOCH-R/MA group than in the DA-EPOCH-R or R-HyperCVAD subgroups (57.1% vs. 38.9% vs. 31.3%; P = 0.016), as was the 5-year PFS (50.0% vs. 38.9% vs. 25.0%; P = 0.035). Autologous stem cell transplantation (ASCT) prolonged the OS and PFS compared with non-ASCT patients (5-year OS: 72.2% vs. 23.3%; P < 0.001; 5-year PFS: 72.2% vs. 16.7 %, P < 0.001). Multivariate analysis identified tumour size, risk stratification, treatment with DA-EPOCH-R/MA, breast irradiation, and ASCT as significant prognostic factors.

Conclusions

DA-EPOCH-R/MA is a promising regimen for PB-DHL, and breast irradiation yields complementary benefits for prognosis. ASCT significantly decreased disease relapse, providing a potential curative PB-DHL intervention and justifying ASCT as first-line therapy for young patients. More effective treatment strategies for PB-DHL patients remain encouraging.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02198-y.

Analysis of real-world data in patients with relapsed/refractory diffuse large B cell lymphoma who received salvage chemotherapy in the rituximab era

Although the overall clinical outcome of patients with diffuse large B cell lymphoma (DLBCL) has significantly improved, some patients still experience relapsed/refractory disease. In the rituximab era, real-world data about relapsed/refractory DLBCL are limited. To clarify the clinical outcome and prognostic factors in these patients, we conducted a retrospective analysis using data from the population-based Osaka Cancer Registry (OCR) from 2010 to 2015. In total, 189 adult patients aged up to 70 years who received CHOP or a CHOP-like regimen in combination with rituximab, as well as a subsequent second-line therapy, were included in the analysis. The median age was 63 years (range, 24-70). Age (> 63 years), the duration of first progression-free survival (PFS), and the use of rituximab in the second-line chemotherapy were prognostic factors for overall survival (OS) after the second-line treatment. In this cohort, 48 and 11 patients received autologous and allogeneic hematopoietic stem cell transplantation (HSCT), respectively. The probabilities of 3-year OS after autologous and allogeneic HSCT were 55.7% and 18.2%, respectively. In conclusion, we found that the clinical outcome of patients with relapsed/refractory DLBCL in the rituximab era was unsatisfactory. Further improvements in treatment strategies, including novel agents, are needed.

Screening Strategy for Detecting Double-Hit Lymphoma in a Resource-Limited Setting

AIM

High-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements [double-hit lymphomas (DHL)] are aggressive lymphomas. Current literature recommends fluorescent in-situ hybridization analysis (FISH) in all cases of diffuse large B-cell lymphoma (DLBCL) to identify cases of DHL. However, this approach is not feasible in a resource-limited setting. We analyzed cases of de novo high-grade B-cell non-Hodgkin lymphoma using histomorphology, immunohistochemistry and FISH to identify which cases need to undergo FISH testing in a resource-limited setting.

MATERIALS AND METHODS

Cases of de novo high-grade B-cell non-Hodgkin lymphoma that included DLBCL, not otherwise specified and B-cell lymphoma unclassifiable (BCLU) with features intermediate between DLBCL and Burkitt lymphoma diagnosed over a period of 5 years were analyzed by Hans algorithm, MYC, BCL2, and Ki67. MYC, BCL2, and BCL6 break apart FISH was tested in selected cases.

RESULTS

One hundred and nine cases were obtained, of which 102 had DLBCL morphology and 7 had BCLU/blastoid morphology. BCL2 expression was noted in 48 cases (44%), MYC in 33 cases (30.3%) and MYC/BCL2 co-expression in 24 cases (22%). FISH testing could be done in 42 consecutive cases, of which 5 cases had MYC and BCL2 co-rearrangement (11.9%) (double-hit) and 2 cases showed rearrangement for only MYC (4.7%) (single-hit). Single-hit lymphoma/DHL showed significant independent positive correlation with BCLU/blastoid morphology, CD10 expression, germinal center B-cell phenotype, and MYC/BCL2 co-expression. The sensitivity and specificity of each parameters include BCLU/blastoid morphology (42% vs. 94%), CD10 positive (50% vs. 88%), germinal center B-cell phenotype (57% vs. 82%), MYC/BCL2 co-expression (85% vs. 80%). Selected candidates for FISH (any one of the above parameters) using this strategy showed a sensitivity and specificity of 100% and 68%, respectively (P=0.001).

CONCLUSION

We propose a highly sensitive screening strategy for detection of MYC/BCL2 rearrangement in high-grade B-cell lymphoma in a resource-limited setting (pending validation in a larger cohort).

Mouse Models of Germinal Center Derived B-Cell Lymphomas

Over the last decades, the revolution in DNA sequencing has changed the way we understand the genetics and biology of B-cell lymphomas by uncovering a large number of recurrently mutated genes, whose aberrant function is likely to play an important role in the initiation and/or maintenance of these cancers. Dissecting how the involved genes contribute to the physiology and pathology of germinal center (GC) B cells -the origin of most B-cell lymphomas- will be key to advance our ability to diagnose and treat these patients. Genetically engineered mouse models (GEMM) that faithfully recapitulate lymphoma-associated genetic alterations offer a valuable platform to investigate the pathogenic roles of candidate oncogenes and tumor suppressors in vivo, and to pre-clinically develop new therapeutic principles in the context of an intact tumor immune microenvironment. In this review, we provide a summary of state-of-the art GEMMs obtained by accurately modelling the most common genetic alterations found in human GC B cell malignancies, with a focus on Burkitt lymphoma, follicular lymphoma, and diffuse large B-cell lymphoma, and we discuss how lessons learned from these models can help guide the design of novel therapeutic approaches for this disease.

The Incidence and Treatment Response of Double Expression of MYC and BCL2 in Patients with Diffuse Large B-Cell Lymphoma: A Systematic Review and Meta-Analysis

MYC/BCL2 protein co-expression (i.e., double expressor) has been shown to be a negative predictor of outcome in diffuse large B-cell lymphoma (DLBCL). We aimed to establish the incidence of double expressor status in patients with de novo DLBCL and identify the predictive value of this biomarker on treatment response through systematic review and meta-analysis. PubMed and Embase were searched for studies published through December 2019 that reported proportions of double expressor DLBCL. The pooled proportions of MYC and BCL2 expression, both alone and in combination, were computed using the inverse variance method for calculating weights and by the DerSimonian-Laird method. The pooled odds ratios (ORs) of complete remission (CR) rate were calculated, and meta-regression analysis was conducted to explore heterogeneity. Forty-one studies (7054 patients) were included. The pooled incidence of double expressor status in DLBCL was 23% (95% confidence interval [CI], 20-26%), with an adjusted estimate of 31% (95% CI, 27-36%). Neither MYC/BCL2 protein cutoff values, race, mean, or median age of included patients, or overall study quality was a significant factor of heterogeneity (p ≥ 0.20). Cases without double expressor status demonstrated a higher probability of CR to rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone treatment (OR, 2.69; 95% CI, 1.55-4.67). Our results reaffirm the predictive power of this important biomarker.

Adverse outcome in follicular lymphoma is associated with MYC rearrangements but not MYC extra copies

Follicular lymphomas (FLs) with MYC rearrangements (MYC-R) and extra copies of MYC (MYC-EC) are rare and the prognosis impact is uncertain. We conducted a retrospective study including 321 FL patients, among whom 259 (81%) had no 8q24 alterations and 62 (19%) were assigned to 8qAlt. Forty-five cases were classified as MYC-EC and six as MYC-R. MYC-R patients were significantly older (P = 0·008), had higher follicular lymphoma international prognostic index (FLIPI) stage (P = 0·05) and β2-microglobulin (β2m; P = 0·05). Among patients treated with immuno-chemotherapy, four presented a MYC-R and 25 a MYC-EC. Univariate analysis showed the absence of significant difference between MYC-EC and normal MYC (MYC-NL) regarding progression-free survival (PFS; HR1·3; 95% CI [0·4-1·6]) and specific overall survival (SOS; HR 1·6; 95% CI [0·4-5·7]). Those results were compared to data from the PRIMA trial. This confirmed that MYC-EC had no impact on PFS (P = 0·86) or SOS (P = 0·9). Conversely, MYC-R was associated with a trend to inferior outcome regarding PFS (HR : 6·1; 95% CI [2·2-17·1]; P = 0·00026), lymphoma-related death (SOS; HR 13·6; 95% CI [2·9-65]; P = 0·00014) and risk of transformation (transformation-free survival (TFS); HR 82·7; 95% CI [14·8-463·4]; P < 0·0001). In conclusion, MYC-EC has no prognostic impact in FL but MYC-R FL tended to be associated with an increased risk of transformation and poorer outcome.

Molecular classification of aggressive lymphomas-past, present, future

Aggressive large B-cell lymphomas (LBCLs) represent a frequent but clinically and molecularly heterogeneous group of tumors. Technological advances over the last decades prompted the development of different classification schemas to either sharpen diagnoses, dissect molecular heterogeneity, predict outcome, or identify rational treatment targets. Despite increased diagnostic precision and a noticeably improved molecular understanding of these lymphomas, clinical perspectives of patients largely remain unchanged. Recently, finished comprehensive genomic studies discovered genetically defined LBCL subtypes that predict outcome, provide insight into lymphomagenesis, and suggest rational therapies with the hope of generating patient-tailored treatments with increased perspective for patients in greatest need. Current and future efforts integrate multiomics studies and/or leverage single-cell technologies and will provide us with an even more fine-grained picture of LBCL biology. Here, we highlight examples of how high-throughput technologies aided in a better molecular understanding of LBCLs and provide examples of how to select rationally designed targeted treatment approaches that might personalize LBCL treatment and eventually improve patients' perspective in the near future.

Matrine suppresses cell growth of diffuse large B-cell lymphoma via inhibiting CaMKIIγ/c-Myc/CDK6 signaling pathway

Background

C-Myc aberrations confer a more aggressive clinic behavior in diffuse large B-cell lymphoma (DLBCL). Matrine is an alkaloid extracted from Sophora flavescens Ait. It possesses anti-cancer property through inhibiting the cell proliferation and inducing the apoptosis. The present study aimed to explore the underlying mechanisms of matrine in suppressing the cell growth of DLBCL.

Methods

The influence of matrine on the viability of cultured DLBCL cell lines SU-DHL-16 and OCI-LY3 cells were determined by CCK-8. Apoptosis and cell cycle were measured by flow cytometry after matrine exposure. Western blot was taken to investigate the expression of activated Caspase-3, cleaved PARP, c-Myc, phospho-c-Myc (Ser62), CaMKIIγ, phospho-CaMKIIγ (Thr287), CDK4 and CDK6 after matrine treatment. Cycloheximide chase analysis was used to determine the c-Myc protein half-lives before and after matrine treatment. Growth salvage analysis was taken by ectopic expression of c-Myc.

Results

In cultured DLBCL cells, matrine suppressed cell viability in a concentration and time dependent fashion. Matrine treated SU-DHL-16 and OCI-LY3 cells for 48 h with IC₅₀ value of 1.76 mM and 4.1 mM, respectively. Matrine induced apoptosis through a caspase-independent pathway and caused G₀/G₁ cell cycle arrest in a concentration dependent manner in DLBCL cells. The protein expression of c-Myc was inhibited while the transcription of c-Myc was not reduced by matrine. c-Myc protein half-lives were decreased from 30.4, 69.4 min to 16.6, 15.9 min after matrine treatment in SU-DHL-16 and OCI-LY3, respectively. As a critical protein kinase of c-Myc, CaMKIIγ phosphorylation at Thr287 was found to be down-regulated and c-Myc phosphorylation at Ser62 was reduced together after matrine treatment in DLBCL. The growth suppression of SU-DHL-16 cells induced by matrine was rescued by over-expression of c-Myc achieved by recombinant adenovirus infection. The decreased expression of CDK6, not CDK4, induced by matrine was rescued by ectopic expression of c-Myc protein.

Conclusions

This study has shown for the first time that matrine suppresses cell growth of DLBCL via inhibiting CaMKIIγ/c-Myc/CDK6 signaling pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03315-0.

Automated 3D scoring of fluorescence in situ hybridization (FISH) using a confocal whole slide imaging scanner

Fluorescence in situ hybridization (FISH) is a technique to visualize specific DNA/RNA sequences within the cell nuclei and provide the presence, location and structural integrity of genes on chromosomes. A confocal Whole Slide Imaging (WSI) scanner technology has superior depth resolution compared to wide-field fluorescence imaging. Confocal WSI has the ability to perform serial optical sections with specimen imaging, which is critical for 3D tissue reconstruction for volumetric spatial analysis. The standard clinical manual scoring for FISH is labor-intensive, time-consuming and subjective. Application of multi-gene FISH analysis alongside 3D imaging, significantly increase the level of complexity required for an accurate 3D analysis. Therefore, the purpose of this study is to establish automated 3D FISH scoring for z-stack images from confocal WSI scanner. The algorithm and the application we developed, SHIMARIS PAFQ, successfully employs 3D calculations for clear individual cell nuclei segmentation, gene signals detection and distribution of break-apart probes signal patterns, including standard break-apart, and variant patterns due to truncation, and deletion, etc. The analysis was accurate and precise when compared with ground truth clinical manual counting and scoring reported in ten lymphoma and solid tumors cases. The algorithm and the application we developed, SHIMARIS PAFQ, is objective and more efficient than the conventional procedure. It enables the automated counting of more nuclei, precisely detecting additional abnormal signal variations in nuclei patterns and analyzes gigabyte multi-layer stacking imaging data of tissue samples from patients. Currently, we are developing a deep learning algorithm for automated tumor area detection to be integrated with SHIMARIS PAFQ.

MYC single-hit large B-cell lymphoma: clinicopathologic difference from MYC-negative large B-cell lymphoma and MYC double-hit/triple-hit lymphoma

MYC-rearranged large B-cell lymphoma with BCL2 and/or BCL6 rearrangement, double-hit (DH) or triple-hit (TH) lymphoma, is associated with poor survival after standard treatment. To investigate the clinical impact of single-hit (SH) MYC rearrangement, we analyzed 241 cases of diffuse large B-cell lymphoma (DLBCL) for MYC, BCL2, and BCL6 rearrangement by fluorescence in situ hybridization. Fifty-five of 241 (22.8%) cases showed MYC rearrangements. Twenty-three cases were diagnosed as DLBCL; 18 as high-grade B-cell lymphoma (HGBCL)-DH; 3 as HGBCL-TH; and 11 as HGBCL, not otherwise specified. Both DH and TH lymphomas showed high-grade morphology (P = 0.002), higher stage (P = 0.022), and more frequent germinal center B-cell-like phenotype (P = 0.008). SH lymphomas displayed high-grade morphology (P = 0.002) but were not different from MYC-negative lymphomas in cell of origin, clinical stage, international prognostic index (IPI), or extranodal involvement. Patients with DH/TH lymphomas had worse overall survival (OS) (P = 0.016) and progression-free survival (PFS) (P < 0.001), while OS and PFS of SH lymphomas were not different from those of MYC-negative lymphomas. There was no survival difference between cases of BCL2 and BCL6 rearrangements. Poorer prognostic factors included higher ECOG class, higher IPI, and DH or TH translocation for OS, and higher IPI and DH or TH translocation for PFS. Higher IPI was an independent prognostic factor for OS and PFS. In conclusion, large B-cell lymphomas with single MYC rearrangement showed high-grade morphology but were otherwise not different from MYC-negative lymphomas.

Karonudib has potent anti-tumor effects in preclinical models of B-cell lymphoma

Chemo-immunotherapy has improved survival in B-cell lymphoma patients, but refractory/relapsed diseases still represent a major challenge, urging for development of new therapeutics. Karonudib (TH1579) was developed to inhibit MTH1, an enzyme preventing oxidized dNTP-incorporation in DNA. MTH1 is highly upregulated in tumor biopsies from patients with diffuse large B-cell lymphoma (DLBCL) and Burkitt lymphoma, hence confirming a rationale for targeting MTH1. Here, we tested the efficacy of karonudib in vitro and in preclinical B-cell lymphoma models. Using a range of B-cell lymphoma cell lines, karonudib strongly reduced viability at concentrations well tolerated by activated normal B cells. In B-cell lymphoma cells, karonudib increased incorporation of 8-oxo-dGTP into DNA, and prominently induced prometaphase arrest and apoptosis due to failure in spindle assembly. MTH1 knockout cell lines were less sensitive to karonudib-induced apoptosis, but were displaying cell cycle arrest phenotype similar to the wild type cells, indicating a dual inhibitory role of the drug. Karonudib was highly potent as single agent in two different lymphoma xenograft models, including an ABC DLBCL patient derived xenograft, leading to prolonged survival and fully controlled tumor growth. Together, our preclinical findings provide a rationale for further clinical testing of karonudib in B-cell lymphoma.

An approach to small lymph node biopsies: pearls and pitfalls of reporting in the real world

Recent advances in interventional radiology have resulted in the utilization of small lymph node biopsies, including fine-needle aspiration (FNA) and core needle biopsy (CNB) as an initial diagnostic tool in hematopathology. A major challenge to the utilization of FNA and CNB is the limited-to-scant tissue often available. We propose delegation of the task of handling biopsy specimens to the laboratory staff by the biopsy operators, in order to optimize the utilization of the specimen. Furthermore, in order to effectively diagnose hematolymphoid neoplasms a variety of ancillary tests including immunohistochemistry, flow cytometry, molecular analysis, florescence in situ hybridization (FISH) are necessary. We propose morphological evaluation coupled with careful utilization of ancillary studies along with clinical correlation to approach the correct diagnosis. Our morphological assessment considers the types of proliferating cell population: mainly small cells, sheets of large cells, or scattered large cells among small cells. This is followed by employment of the corresponding immunopanel to assess the differential diagnosis in each of the three categories. We also elaborate on the importance for pathologists to become proficient in understanding the limitations of small tissue biopsies as well as the differences in interpretation, and wording their reports to help clinicians and direct them to further investigate and/or to re-biopsy when necessary.

CS2164 and Venetoclax Show Synergistic Antitumoral Activities in High Grade B-Cell Lymphomas With MYC and BCL2 Rearrangements

High-grade B-cell lymphoma with concurrent MYC and BCL2 rearrangements (HGBL-DHL) is a rare, aggressive mature B-cell malignancy with a high likelihood of treatment failure following front-line immunochemotherapies. Patients with HGBL-DHL who develop a relapsed or refractory disease have little effective therapeutic strategies and show very poor clinical outcomes, thus calling for development of novel therapies for this specific patient population. In this study, we investigated the preclinical anti-lymphoma efficacies and potential mechanism of action of a novel treatment approach, combining the BCL2 inhibitor venetoclax with CS2164, a new orally active multitarget inhibitor, in HGBL-DHL models. This combination therapy exhibited a robust synergistic cytotoxicity against HGBL-DHL cells, evidenced by cooperatively inducing loss of cell viability and promoting cell apoptosis. Moreover, coadministration of CS2164 and venetoclax resulted in significant superior suppression of HGBL-DHL cell growth and remarkably abrogated tumor burden in a HGBL-DHL-xenografted mouse model. The synergistic lethality of CS2164 and venetoclax in HGBL-DHL cells was associated with induction of DNA damage and impairment of DNA repair ability. Of importance, the combined treatment almost abolished the expression of both BCL2 and MYC, two hallmark proteins of HGBL-DHL, and substantially blunted the activity of PI3K/AKT/mTOR signaling cascade. In addition, MCL1 and BCL-XL, two well-characterized contributors for venetoclax resistance, were significantly lessened in the presence of CS2164 and venetoclax, thus leading to the accumulation of proapoptotic proteins BAX and PUMA and then initiating the intrinsic apoptosis pathway. Taken together, these findings suggest that the regimen of CS2164 and venetoclax is highly effective to eliminate HGBL-DHL cells in the preclinical setting, warranting further clinical investigations of this regimen for the treatment of unfavorable HGBL-DHL patients.

Diagnostic Approach for Double-Hit and Triple-Hit Lymphoma Based on Immunophenotypic and Cytogenetic Characteristics of Bone Marrow Specimens

BACKGROUND

High-grade B-cell lymphoma with rearrangements of MYC and BCL2 and/or BCL6 (BCL2/BCL6), also known as double-hit lymphoma (DHL) and/or triple-hit lymphoma (THL), is a new entity of B-cell lymphoma in the 2017 WHO Classification. We retrospectively investigated D/THL and their clinico-laboratory features among cases of large B-cell lymphoma involving the bone marrow (BM), including diffuse large B-cell lymphoma, Burkitt lymphoma, and B-cell lymphomas with medium to large lymphoid cells, by additional FISH analysis of BM aspirates.

METHODS

A total of 111 patients diagnosed with aggressive B-cell lymphomas or B-cell lymphoma involving the BM with medium to large-sized malignant lymphocytes were reviewed from January 2000 to January 2018. Patients with available BM aspirates were evaluated by immunophenotyping by flow cytometry, chromosome, and FISH analysis for MYC and/or BCL2/BCL6 rearrangements.

RESULTS

In total, 23/111 (20.7%) showed MYC rearrangement, and eight (7.2%) were reclassified as D/THL on BM after FISH analysis for MYC and BCL2/BCL6. The detection of CD5(-)/CD10(+) based on flow cytometry was strongly associated with D/THL. A complex karyotype with aberrations related to regions in MYC and BCL2/BCL6 was significantly associated with D/THL. When the MYC FISH results of 28 BM aspirates and formalin-fixed paraffin-embedded tissue specimens were compared, 14% were discrepant.

CONCLUSIONS

Immunophenotypic and cytogenetic characteristics facilitate the diagnosis of D/THL in the cases with BM-involving aggressive B-cell lymphomas.

Impact of Omission/Reduction of Vincristine From R-CHOP in Treatment of DLBCL

BACKGROUND

The R-CHOP regimen (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone) is the standard therapy for patients with diffuse large B-cell lymphoma (DLBCL). However, vincristine is sometimes omitted or reduced owing to side effects.

MATERIALS AND METHODS

We retrospectively reviewed newly diagnosed patients with DLBCL with R-CHOP-like chemotherapy in our institute from January 2005 to February 2018 to investigate whether the omission/reduction of vincristine reduced the efficacy of the treatment. We compared the overall survival (OS) with and without the omission/reduction of vincristine from the R-CHOP regimen.

RESULTS

A total of 576 cases were reviewed, and vincristine was omitted/reduced in 50 (9%) patients. The 4-year OS with and without vincristine omission/reduction for relative dose intensity < 80%, 50%, and 25% was 70% versus 82% (P = .035), 70% versus 82% (P = .085), and 53% versus 82% (P = .0007). In a multivariate analysis, adjusting for international prognostic index risk factors, a statistically significant, poor OS was indicated in the patients with relative dose intensity < 25%.

CONCLUSIONS

Excessive dose omission/reduction of vincristine might lead to a substantial loss of efficacy of R-CHOP therapy.

DNA Copy Number Changes in Diffuse Large B Cell Lymphomas

Copy number aberrations (CNV/CNA) represent a major contribution to the somatic mutation landscapes in cancers, and their identification can lead to the discovery of oncogenetic targets as well as improved disease (sub-) classification. Diffuse large B cell lymphoma (DLBCL) is the most common lymphoma in Western Countries and up to 40% of the affected individuals still succumb to the disease. DLBCL is an heterogenous group of disorders, and we call DLBCL today is not necessarily the same disease of a few years ago. This review focuses on types and frequencies of regional DNA CNVs in DLBCL, not otherwise specified, and in two particular conditions, the transformation from indolent lymphomas and the DLBCL in individuals with immunodeficiency.

Molecular Genetics of Relapsed Diffuse Large B-Cell Lymphoma: Insight into Mechanisms of Therapy Resistance

The majority of patients with diffuse large B-cell lymphoma (DLBCL) can be treated successfully with a combination of chemotherapy and the monoclonal anti-CD20 antibody rituximab. Nonetheless, approximately one-third of the patients with DLBCL still experience relapse or refractory (R/R) disease after first-line immunochemotherapy. Whole-exome sequencing on large cohorts of primary DLBCL has revealed the mutational landscape of DLBCL, which has provided a framework to define novel prognostic subtypes in DLBCL. Several studies have investigated the genetic alterations specifically associated with R/R DLBCL, thereby uncovering molecular pathways linked to therapy resistance. Here, we summarize the current state of knowledge regarding the genetic alterations that are enriched in R/R DLBCL, and the corresponding pathways affected by these gene mutations. Furthermore, we elaborate on their potential role in mediating therapy resistance, also in connection with findings in other B-cell malignancies, and discuss alternative treatment options. Hence, this review provides a comprehensive overview on the gene lesions and molecular mechanisms underlying R/R DLBCL, which are considered valuable parameters to guide treatment.

Transcriptome profiling reveals an integrated mRNA-lncRNA signature with predictive value for long-term survival in diffuse large B-cell lymphoma

For patients with diffuse large B-cell lymphoma (DLBCL), survival at 24 months is a milestone for long-term survival. The purpose of this study was to develop a multigene risk score (MGRS) to refine the International Prognostic Index (IPI) model to identify patients with DLBCL at high risk of death within 24 months. Using a robust statistical strategy, we built a MGRS incorporating nine mRNAs and two lncRNAs. Stratification and multivariable Cox regression analysis confirmed the MGRS as an independent risk factor. A nomogram based on IPI+MGRS model was constructed and its calibration plot showed close agreement between predicted 2-year survival rate and observed rate. The 2-year AUC was bigger with the IPI+MGRS model (ΔAUC=0.162; 95%CI 0.1295–0.1903) than with the IPI model, and the IPI+MGRS model more accurately predicted the prognostic risk of DLBCL. The 2-year survival decision curve revealed the IPI+MGRS model was more useful clinically than the IPI model. Functional enrichment analysis showed that the MGRS correlated with cell cycle, DNA replication and repair. The results were validated using an independent external dataset. In conclusion, we successfully developed an integrated mRNA–lncRNA signature to refine the IPI model for predicting long-term survival of patients with DLBCL.

Immunophenotypic Landscape and Prognosis of Diffuse Large B-Cell Lymphoma with MYC/BCL2 Double Expression: An Analysis of A Prospectively Immunoprofiled Cohort

Simple Summary

Diffuse large B-cell lymphoma (DLBCL) with MYC/BCL2 double-expression (DE), a recently proposed poor prognostic group, can be easily identified by immunohistochemistry in routine clinical practice. However, clinical outcomes of DE-DLBCL patients vary immensely after R-CHOP immunochemotherapy and prognostic impact of MYC/BCL2-DE was conflicting according to the cell-of-origin, i.e., between germinal center-B-cell (GCB)- and non-GCB-DLBCLs. This implies the heterogeneity within DE-DLBCLs and emphasizes a need for proper risk stratification to select the patients who require more intensive therapy. By analyzing a prospectively immunoprofiled cohort of consecutively diagnosed DLBCL patients, we confirmed the poor prognostic value of MYC/BCL2-DE in DLBCL patients treated with R-CHOP irrespective of the cell-of-origin and international prognostic index. DE-DLBCLs with a concurrent risk factor, especially, elevated serum lactate dehydrogenase (LDH), had the worst survival and DE-DLBCL patients with normal LDH had clinical outcomes similar to those of non-DE-DLBCL patients. Risk stratification of DE-DLBCL based on serum LDH may guide clinical decision-making for DE-DLBCL patients.

Abstract

Diffuse large B-cell lymphoma (DLBCL) patients with MYC/BCL2 double expression (DE) show poor prognosis and their clinical outcomes after R-CHOP therapy vary immensely. We investigated the prognostic value of DE in aggressive B-cell lymphoma patients (n = 461), including those with DLBCL (n = 417) and high-grade B-cell lymphoma (HGBL; n = 44), in a prospectively immunoprofiled cohort. DE was observed in 27.8% of DLBCLs and 43.2% of HGBLs (p = 0.058). DE-DLBCL patients were older (p = 0.040) and more frequently exhibited elevated serum LDH levels (p = 0.002), higher international prognostic index (IPI; p = 0.042), non-germinal-center B-cell phenotype (p < 0.001), and poor response to therapy (p = 0.042) compared to non-DE-DLBCL patients. In R-CHOP-treated DLBCL patients, DE status predicted poor PFS and OS independently of IPI (p < 0.001 for both). Additionally, in DE-DLBCL patients, older age (>60 years; p = 0.017), involvement of ≥2 extranodal sites (p = 0.021), bone marrow involvement (p = 0.001), high IPI (p = 0.017), CD10 expression (p = 0.006), poor performance status (p = 0.028), and elevated LDH levels (p < 0.001) were significantly associated with poor OS. Notably, DE-DLBCL patients with normal LDH levels exhibited similar PFS and OS to those of patients with non-DE-DLBCL. Our findings suggest that MYC/BCL2 DE predicts poor prognosis in DLBCL. Risk stratification of DE-DLBCL patients based on LDH levels may guide clinical decision-making for DE-DLBCL patients.

Impact of MYC on Anti-Tumor Immune Responses in Aggressive B Cell Non-Hodgkin Lymphomas: Consequences for Cancer Immunotherapy

Simple Summary

The human immune system has several mechanisms to attack and eliminate lymphomas. However, the MYC oncogene is thought to facilitate escape from this anti-tumor immune response. Since patients with MYC overexpressing lymphomas face a significant dismal prognosis after treatment with standard immunochemotherapy, understanding the role of MYC in regulating the anti-tumor immune response is highly relevant. In this review, we describe the mechanisms by which MYC attenuates the anti-tumor immune responses in B cell non-Hodgkin lymphomas. We aim to implement this knowledge in the deployment of novel immunotherapeutic approaches. Therefore, we also provide a comprehensive overview of current immunotherapeutic options and we discuss potential future treatment strategies for MYC overexpressing lymphomas.

Abstract

Patients with MYC overexpressing high grade B cell lymphoma (HGBL) face significant dismal prognosis after treatment with standard immunochemotherapy regimens. Recent preclinical studies indicate that MYC not only contributes to tumorigenesis by its effects on cell proliferation and differentiation, but also plays an important role in promoting escape from anti-tumor immune responses. This is of specific interest, since reversing tumor immune inhibition with immunotherapy has shown promising results in the treatment of both solid tumors and hematological malignancies. In this review, we outline the current understanding of impaired immune responses in B cell lymphoid malignancies with MYC overexpression, with a particular emphasis on diffuse large B cell lymphoma. We also discuss clinical consequences of MYC overexpression in the treatment of HGBL with novel immunotherapeutic agents and potential future treatment strategies.

Mouse double minute 2 amplification in oesophageal squamous cell carcinoma is associated with better outcome

AIMS

This study aimed to determine the frequency of mouse double minute 2 (MDM2) amplification in oesophageal squamous cell carcinomas (ESCC) and to clarify its prognostic significance.

METHODS AND RESULTS

We investigated MDM2 amplification on tissue microarrays using fluorescence in-situ hybridisation and analysed its correlations with clinicopathological features and outcomes in 515 Chinese ESCC patients. MDM2 amplifications were found in 37 of 515 ESCC patients (7.2%). They were significantly negatively correlated with tumour size (P = 0.045), disease progression (P = 0.002) and death (P = 0.003). Univariate analysis showed that the following clinicopathological factors were associated with disease-free survival (DFS) and overall survival (OS): differentiation (P = 0.025 for DFS and P = 0.061 for OS), vessel invasion (P = 0.001 and P = 0.002), nerve invasion (P = 0.009 and P = 0.001), clinical stage (P < 0.001 and P < 0.001) and MDM2 amplification (P = 0.012 and P = 0.014). Multivariate Cox regression analysis showed that MDM2 amplification was an independent prognostic factor for improved outcomes (P = 0.023 for DFS, P = 0.027 for OS) and the clinical stage was an independent prognostic factor for poor outcomes (P < 0.001). When survival analyses were conducted at different clinical stages, MDM2 amplification was associated with longer DFS and OS in stages I-II ESCC (P = 0.003 for DFS and P = 0.003 for OS), but there was no significant survival difference in stages III-IVa ESCC.

CONCLUSIONS

MDM2 amplification was significantly correlated with an improved patient outcome, especially in stage I and II disease, and was verified as an independent prognostic factor in our patients. Therefore, MDM2 amplification may be a potential biomarker for risk stratification of the lower stages of ESCC.

High-grade B-cell lymphoma with MYC and BCL6 rearrangements presenting as a cervical mass

Lymphoid malignancies represent 0. 008% of all cervical tumours. While uncommon, lymphoid malignancies of the gynaecological tract require careful diagnosis and classification to ensure appropriate treatment. We present a case of a 54-year-old woman with HIV who presented with urinary and faecal incontinence for 2 weeks, associated with the feeling of a mass in her vagina. A smooth flesh-coloured pelvic mass was seen on physical examination, and a transvaginal biopsy revealed infiltration of atypical lymphoid cells with fluorescence in situ hybridisation positive for MYC and BCL6, and negative for IGH/BCL2. Bone marrow and cerebral spinal fluid analysis also showed involvement by atypical lymphocytes. She was diagnosed with stage IV high-grade B-cells lymphoma (HGBLs) with MYC and BCL6 rearrangements. She was given R-CODOX-M plus IVAC with no evidence of disease at 4-month follow-up. To our knowledge, this is the first literature report of a HGBL with MYC and BCL6 rearrangement presenting as a cervical mass.

Molecular Classification of Large B-Cell Non-Hodgkin Lymphoma

Large B-cell lymphomas (LBCLs) represent a frequent but clinically and morphologically heterogeneous group of tumors. Technological advances over the last 2 decades prompted the development of new classification schemas to sharpen diagnoses, dissect molecular heterogeneity, and identify rational treatment targets. Despite increased molecular understanding of these lymphomas, the clinical perspectives of patients largely remain unchanged. Recently finished comprehensive genomic studies discovered genetically defined LBCL subtypes that predict outcome, provide insight into lymphomagenesis, and suggest rational therapies with the hope of generating patient-tailored treatments with increased perspective for patients in greatest need. Here, we summarize notable examples of how high-throughput technologies aided in better molecular understanding of LBCLs and provided examples of rationally designed targeted treatments.

Novel Therapies Potentially Available for Pediatric B-Cell Non-Hodgkin Lymphoma

Burkitt lymphoma, diffuse large B-cell lymphoma (DLBCL), and primary mediastinal B-cell lymphoma are the most common aggressive pediatric mature B-cell non-Hodgkin lymphomas (B-NHLs). Despite excellent survival with current chemotherapy regimens, therapy for Burkitt lymphoma and DLBCL has a high incidence of short- and long-term toxicities. Patients who experience relapse generally have a very poor prognosis. Therefore, novel approaches using targeted therapies to reduce toxicities and improve outcomes in the relapse setting are needed. The addition of rituximab, a monoclonal antibody against CD20, to upfront therapy has improved survival outcomes for high-risk patients and may allow decreased total chemotherapy in those with low-risk disease. Antibody-drug conjugates have been combined with chemotherapy in relapsed/refractory (R/R) NHL, and multiple antibody-drug conjugates are in development. Additionally, bispecific T-cell-engaging antibody constructs and autologous CAR T-cells have been successful in the treatment of R/R acute leukemias and are now being applied to R/R B-NHL with some successes. PD-L1 and PD-L2 on tumor cells can be targeted with checkpoint inhibitors, which restore T-cell-mediated immunity and antitumor responses and can be added to conventional chemotherapy and immune-directed therapies to augment responses. Lastly, trials of small molecule inhibitors targeting cell signaling pathways in NHL subtypes are underway. This article reviews many of the targeted therapies under development that could be considered for future trials in R/R pediatric mature B-NHL.

Combination of the dual PIM/PI3-kinase inhibitor IBL-202 and venetoclax is effective in diffuse large B-cell lymphoma

Current chemoimmunotherapy is unable to cure up to 40% of patients diagnosed with diffuse large B-cell lymphoma (DLBCL). Targeting the mechanisms by which DLBCL evades apoptosis is crucial to overcoming treatment failure in this heterogeneous disease as both current and novel treatments depend on the apoptosis of malignant cells. Despite the common overexpression of BCL-2, venetoclax is ineffective in DLBCL due to MCL-1 co-expression. This is driven by pro-growth PI3-kinase signaling, which is promoted in turn by PIM kinases. In this study, the novel dual-kinase inhibitor, IBL-202, was combined with venetoclax against a panel of DLBCL cell lines that have variable expression of pro-survival proteins. The results support the efficacy of simultaneously targeting inter-related molecules to overcome apoptotic escape in this biologically heterogeneous disease. As venetoclax, pan-PIM-kinase and pan-PI3-kinase inhibitors have, or are currently being studied in clinical trials, it may be rational to consider these drugs in combination for the treatment of DLBCL.

Identification of "Double Hit" Lymphomas Using Updated WHO Criteria: Insights From Routine MYC Immunohistochemistry in 272 Consecutive Cases of Aggressive B-Cell Lymphomas

Aggressive lymphomas with MYC and BCL2 and/or BCL6 translocations ("double hit" lymphomas, DHL) represent a distinct diagnostic category in the updated World Health Organization (WHO) classification. The diagnostic yield of MYC immunohistochemistry (IHC) for the identification of DHL is currently uncertain. MYC IHC was performed in 272 consecutive cases of aggressive B-cell lymphoma, and results correlated with fluorescence in situ hybridization (FISH) for MYC translocations. Among 156 patients with IHC and FISH data, MYC IHC identified MYC translocations with 89% sensitivity, 38% specificity, 92% negative predictive value, and 29% positive predictive value. Three of 15 (20%) of DHL were MYC IHC negative. One case contained a MYC translocation detectable IGH/MYC fusion probes but not MYC break-apart probes. A subset of DHL lack MYC protein expression, and recognition of this subset of cases requires FISH testing. These results provide an appropriate diagnostic algorithm for implementation of 2016 WHO diagnostic criteria.