Toward a New Molecular Taxonomy of Diffuse Large B-cell Lymphoma

IRF8-mutant B cell lymphoma evades immunity through a CD74-dependent deregulation of antigen processing and presentation in MHCII complexes

The mechanism by which interferon regulatory factor 8 (IRF8) mutation contributes to lymphomagenesis is unknown. We modeled IRF8 variants in B cell lymphomas and found that they affected the expression of regulators of antigen presentation. Expression of IRF8 mutants in murine B cell lymphomas suppressed CD4, but not CD8, activation elicited by antigen presentation and downmodulated CD74 and human leukocyte antigen (HLA) DM, intracellular regulators of antigen peptide processing/loading in the major histocompatibility complex (MHC) II. Concordantly, mutant IRF8 bound less efficiently to the promoters of these genes. Mice harboring IRF8 mutant lymphomas displayed higher tumor burden and remodeling of the tumor microenvironment, typified by depletion of CD4, CD8, and natural killer cells, increase in regulatory T cells and T follicular helper cells. Deconvolution of bulk RNA sequencing data from IRF8-mutant human diffuse large B cell lymphoma (DLBCL) recapitulated part of the immune remodeling detected in mice. We concluded that IRF8 mutations contribute to DLBCL biology by facilitating immune escape.

Tumor purity-related genes for predicting the prognosis and drug sensitivity of DLBCL patients

Background

Diffuse large B-cell lymphoma (DLBCL) is the predominant type of malignant B-cell lymphoma. Although various treatments have been developed, the limited efficacy calls for more and further exploration of its characteristics.

Methods

Datasets from the Gene Expression Omnibus (GEO) database were used for identifying the tumor purity of DLBCL. Survival analysis was employed for analyzing the prognosis of DLBCL patients. Immunohistochemistry was conducted to detect the important factors that influenced the prognosis. Drug-sensitive prediction was performed to evaluate the value of the model.

Results

VCAN, CD3G, and C1QB were identified as three key genes that impacted the outcome of DLBCL patients both in GEO datasets and samples from our center. Among them, VCAN and CD3G+ T cells were correlated with favorable prognosis, and C1QB was correlated with worse prognosis. The ratio of CD68 + macrophages and CD8 + T cells was associated with better prognosis. In addition, CD3G+T cells ratio was significantly correlated with CD68 + macrophages, CD4 + T cells, and CD8 +T cells ratio, indicating it could play an important role in the anti-tumor immunity in DLBCL. The riskScore model constructed based on the RNASeq data of VCAN, C1QB, and CD3G work well in predicting the prognosis and drug sensitivity.

Conclusions

VCAN, CD3G, and C1QB were three key genes that influenced the tumor purity of DLBCL, and could also exert certain impact on drug sensitivity and prognosis of DLBCL patients.

Funding

This work is supported by the Shenzhen High-level Hospital Construction Fund and CAMS Innovation Fund for Medical Sciences (CIFMS) (2022-I2M-C&T-B-062).

Cuproptosis-related lncRNA signature as a prognostic tool and therapeutic target in diffuse large B cell lymphoma

Cuproptosis is a newly defined form of programmed cell death that relies on mitochondria respiration. Long noncoding RNAs (lncRNAs) play crucial roles in tumorigenesis and metastasis. However, whether cuproptosis-related lncRNAs are involved in the pathogenesis of diffuse large B cell lymphoma (DLBCL) remains unclear. This study aimed to identify the prognostic signatures of cuproptosis-related lncRNAs in DLBCL and investigate their potential molecular functions. RNA-Seq data and clinical information for DLBCL were collected from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Cuproptosis-related lncRNAs were screened out through Pearson correlation analysis. Utilizing univariate Cox, least absolute shrinkage and selection operator (Lasso) and multivariate Cox regression analysis, we identified seven cuproptosis-related lncRNAs and developed a risk prediction model to evaluate its prognostic value across multiple groups. GO and KEGG functional analyses, single-sample GSEA (ssGSEA), and the ESTIMATE algorithm were used to analyze the mechanisms and immune status between the different risk groups. Additionally, drug sensitivity analysis identified drugs with potential efficacy in DLBCL. Finally, the protein-protein interaction (PPI) network were constructed based on the weighted gene co-expression network analysis (WGCNA). We identified a set of seven cuproptosis-related lncRNAs including LINC00294, RNF139-AS1, LINC00654, WWC2-AS2, LINC00661, LINC01165 and LINC01398, based on which we constructed a risk model for DLBCL. The high-risk group was associated with shorter survival time than the low-risk group, and the signature-based risk score demonstrated superior prognostic ability for DLBCL patients compared to traditional clinical features. By analyzing the immune landscapes between two groups, we found that immunosuppressive cell types were significantly increased in high-risk DLBCL group. Moreover, functional enrichment analysis highlighted the association of differentially expressed genes with metabolic, inflammatory and immune-related pathways in DLBCL patients. We also found that the high-risk group showed more sensitivity to vinorelbine and pyrimethamine. A cuproptosis-related lncRNA signature was established to predict the prognosis and provide insights into potential therapeutic strategies for DLBCL patients.

Ethyl pyruvate attenuates cellular adhesion and proliferation of diffuse large B-cell lymphoma by targeting c-Jun

Diffuse large B-cell lymphoma (DLBCL) stands out as the most common type of malignant cancer, representing the majority of cases of non-Hodgkin's lymphoma. Ethyl pyruvate (EP) is a derivative of pyruvic acid and found to have potent anti-tumor properties. Despite its potential benefits, the impact of EP on DLBCL remains ambiguous. Our objective is to elucidate the role of EP in modulating the development of DLBCL. Analysis of cholecystokinin-8 (CCK-8) revealed that treatment with EP significantly diminished the viability of DLBCL cells. Furthermore, EP administration suppressed colony formation and hindered cell adhesion and invasion in DLBCL cells. Examination of cell cycle progression showed that EP treatment induced arrest at the G1 phase and subsequently reduced the S phase population in DLBCL cells. EP treatment consistently exhibited apoptosis-inducing properties in Annexin-V assays, and notably downregulated the expression of Bcl-2 while increasing levels of proapoptotic cleaved caspase 3 and BAX in DLBCL cells. Additionally, EP treatment decreased the overexpression of c-Jun in c-Jun-transfected DLBCL cells. Further, EP demonstrated DNA-damaging effects in TUNEL assays. In vivo, xenograft animal models revealed that EP treatment significantly mitigated DLBCL tumor growth and suppressed DLBCL cell adhesion to bone marrow stromal cells. In summary, these findings suggest that EP mitigates DLBCL progression by inducing apoptosis, inducing cell cycle arrest, and promoting DNA damage.

Analyzing the involvement of diverse cell death-related genes in diffuse large B-cell lymphoma using bioinformatics techniques

Diffuse large B-cell lymphoma (DLBCL) stands as the most prevalent subtype of non-Hodgkin's lymphoma and exhibits significant heterogeneity. Various forms of programmed cell death (PCD) have been established to have close associations with tumor onset and progression. To this end, this study has compiled 16 PCD-related genes. The investigation delved into genes linked with prognosis, constructing risk models through consecutive application of univariate Cox regression analysis and Lasso-Cox regression analysis. Furthermore, we employed RT-qPCR to validate the mRNA expression levels of certain diagnosis-related genes. Subsequently, the models underwent validation through KM survival curves and ROC curves, respectively. Additionally, nomogram models were formulated employing prognosis-related genes and risk scores. Lastly, disparities in immune cell infiltration abundance and the expression of immune checkpoint-associated genes between high- and low-risk groups, as classified by risk models, were explored. These findings contribute to a more comprehensive understanding of the role played by the 16 PCD-associated genes in DLBCL, shedding light on potential novel therapeutic strategies for the condition.

A retrospective analysis of the clinicopathological features and prognostic value of MAPK12 protein expression in diffuse large B-cell lymphoma

PURPOSE

Mitogen-activated protein kinase 12 (MAPK12), also known as p38γ, is a member of the p38 MAPK family and plays a crucial role in tumor occurrence and invasion. However, there is still uncertainty regarding MAPK12 involvement in diffuse large B-cell lymphoma (DLBCL).

METHODS

Our study investigated the expression of MAPK12 mRNA in various types of cancer using bioinformatic analysis. Furthermore, we performed immunohistochemistry (IHC) to detect the expression of MAPK12 in patients with DLBCL and compared clinical indicators and survival rates.

RESULTS

We found that the high expression rate of MAPK12 was 43.1% in DLBCL patients. Several clinical indicators, including IPI scores, Hans classifications, LDH levels, and Ki-67 expression were closely associated with MAPK12 expression. Survival analysis revealed that higher expression of MAPK12 was significantly correlated with shorter progression-free survival (PFS) and overall survival (OS) in DLBCL patients. In addition, both univariate and multivariate analyses revealed IPI score, MAPK12 expression, and rituximab use as the independent OS risk factors (P < 0.05). To explore the functional role of MAPK12 in DLBCL, weighted gene co-expression network analysis (WGCNA) and gene ontology (GO) were used to confirm the involvement of MAPK12 in the regulation of type II interferon production, positive regulation of lymphocyte proliferation, and other related biological processes.

CONCLUSION

DLBCL patients have poor prognoses when MAPK12 levels are high, which is expected to be a therapeutic target and prognostic factor.

A novel anoikis-related signature predicts prognosis risk and treatment responsiveness in diffuse large B-cell lymphoma

BACKGROUND

Although anoikis plays a role in cancer metastasis and aggressiveness, it has rarely been reported in diffuse large B cell lymphoma (DLBCL).

METHODS

We obtained RNA sequencing data and matched clinical data from the GEO database. An anoikis-related genes (ARGs)-based risk signature was developed in GSE10846 training cohort and validated in three other cohorts. Additionally, we predicted half-maximal inhibitory concentration (IC50) of drugs based on bioinformatics method and obtained the actual IC50 to some chemotherapy drugs via cytotoxicity assay.

RESULTS

The high-risk group, as determined by our signature, was associated with worse prognosis and an immunosuppressive environment in DLBCL. Meanwhile, the nomogram based on eight variables had more accurate ability in forecasting the prognosis than the international prognostic index in DLBCL. The prediction of IC50 indicated that DLBCL patients in the high-risk group were more sensitive to doxorubicin, IPA-3, lenalidomide, gemcitabine, and CEP.701, while patients in the low-risk group were sensitive to cisplatin and dasatinib. Consistent with the prediction, cytotoxicity assay suggested the higher sensitivity to doxorubicin and gemcitabine and the lower sensitivity to dasatinib in the high-risk group in DLBCL.

CONCLUSION

The ARG-based signature may provide a promising direction for prognosis prediction and treatment optimization for DLBCL patients.

Comprehensive molecular classification predicted microenvironment profiles and therapy response for HCC

BACKGROUND AND AIMS

Tumor microenvironment (TME) heterogeneity leads to a discrepancy in survival prognosis and clinical treatment response for patients with HCC. The clinical applications of documented molecular subtypes are constrained by several issues.

APPROACH AND RESULTS

We integrated 3 single-cell data sets to describe the TME landscape and identified 6 prognosis-related cell subclusters. Unsupervised clustering of subcluster-specific markers was performed to generate transcriptomic subtypes. The predictive value of these molecular subtypes for prognosis and treatment response was explored in multiple external HCC cohorts and the Xiangya HCC cohort. TME features were estimated using single-cell immune repertoire sequencing, mass cytometry, and multiplex immunofluorescence. The prognosis-related score was constructed based on a machine-learning algorithm. Comprehensive single-cell analysis described TME heterogeneity in HCC. The 5 transcriptomic subtypes possessed different clinical prognoses, stemness characteristics, immune landscapes, and therapeutic responses. Class 1 exhibited an inflamed phenotype with better clinical outcomes, while classes 2 and 4 were characterized by a lack of T-cell infiltration. Classes 5 and 3 indicated an inhibitory tumor immune microenvironment. Analysis of multiple therapeutic cohorts suggested that classes 5 and 3 were sensitive to immune checkpoint blockade and targeted therapy, whereas classes 1 and 2 were more responsive to transcatheter arterial chemoembolization treatment. Class 4 displayed resistance to all conventional HCC therapies. Four potential therapeutic agents and 4 targets were further identified for high prognosis-related score patients with HCC.

CONCLUSIONS

Our study generated a clinically valid molecular classification to guide precision medicine in patients with HCC.

Aggressive B-cell non-Hodgkin lymphomas: a report of the lymphoma workshop of the 20th meeting of the European Association for Haematopathology

Aggressive B-cell non-Hodgkin lymphomas are a heterogeneous group of diseases and our concepts are evolving as we learn more about their clinical, pathologic, molecular genetic features. Session IV of the 2020 EAHP Workshop covered aggressive, predominantly high-grade B-cell lymphomas, many that were difficult to classify. In this manuscript, we summarize the features of the submitted cases and highlight differential diagnostic difficulties. We specifically review issues related to high-grade B-cell lymphomas (HGBCLs) with MYC and BCL2 and/or BCL6 rearrangements including TdT expression in these cases, HGBCL, not otherwise specified, large B-cell lymphomas with IRF4 rearrangement, high-grade/large B-cell lymphomas with 11q aberration, Burkitt lymphoma, and pleomorphic mantle cell lymphoma. Since the workshop, the 5th edition of the WHO Classification for Haematolymphoid Tumours (WHO-HAEM5) and International Consensus Classification (ICC) 2022 were published. We endeavor to use the updated terminology.

Distribution and clinical impact of molecular subtypes with dark zone signature of DLBCL in a Japanese real-world study

The distribution and clinical impact of cell-of-origin (COO) subtypes of diffuse large B-cell lymphoma (DLBCL) outside Western countries remain unknown. Recent literature also suggests that there is an additional COO subtype associated with the germinal center dark zone (DZ) that warrants wider validation to generalize clinical relevance. Here, we assembled a cohort of Japanese patients with untreated DLBCL and determined the refined COO subtypes, which include the DZ signature (DZsig), using the NanoString DLBCL90 assay. To compare the distribution and clinical characteristics of the molecular subtypes, we used a data set from the cohort of British Columbia Cancer (BCC) (n = 804). Through the 1050 patient samples on which DLBCL90 assay was successfully performed in our cohort, 35%, 45%, and 6% of patients were identified to have germinal center B-cell-like (GCB) DLBCL, activated B-cell-like (ABC) DLBCL, and DZsig-positive (DZsigpos) DLBCL, respectively, with the highest prevalence of ABC-DLBCL, differing significantly from the BCC result (P < .001). GCB-DLBCL, ABC-DLBCL, and DZsigpos-DLBCL were associated with 2-year overall survival rates of 88%, 75%, and 66%, respectively (P < .0001), with patients with DZsigpos-DLBCL having the poorest prognosis. In contrast, GCB-DLBCL without DZsig showed excellent outcomes after rituximab-containing immunochemotherapy. DZsigpos-DLBCL was associated with the significant enrichment of tumors with CD10 expression, concurrent MYC/BCL2 expression, and depletion of microenvironmental components (all, P < .05). These results provide evidence of the distinct distribution of clinically relevant molecular subtypes in Japanese DLBCL and that refined COO, as measured by the DLBCL90 assay, is a robust prognostic biomarker that is consistent across geographical areas.

A novel telomere-related genes model for predicting prognosis and treatment responsiveness in diffuse large B-cell lymphoma

Diffuse large B cell lymphoma (DLBCL) is a highly heterogeneous disease with diverse clinical and molecular features. Telomere maintenance is widely present in tumors, but there is a lack of relevant reports on the role of telomere-related genes (TRGs) in DLBCL. In this study, we used consensus clustering based on TRGs expression to identify two molecular clusters with distinct prognoses and immune cell infiltration. We developed a TRGs scoring model using univariate Cox regression and LASSO regression in the GSE10846 training cohort. DLBCL patients in the high-risk group had a worse prognosis than those in the low-risk group, as revealed by Kaplan-Meier curves. The scoring model was validated in the GSE10846 testing cohort and GSE87371 cohort, respectively. The high-risk group was characterized by elevated infiltration of activated DCs, CD56 dim natural killer cells, myeloid-derived suppressor cells, monocytes, and plasmacytoid DCs, along with reduced infiltration of activated CD4 T cells, Type 2 T helper cells, γδ T cells, NK cells, and neutrophils. Overexpression of immune checkpoints, such as PDCD1, CD274, and LAG3, was observed in the high-risk group. Furthermore, high-risk DLBCL patients exhibited increased sensitivity to bortezomib, rapamycin, AZD6244, and BMS.536924, while low-risk DLBCL patients showed sensitivity to cisplatin and ABT.263. Using RT-qPCR, we found that three protective model genes, namely TCEAL7, EPHA4, and ELOVL4, were down-regulated in DLBCL tissues compared with control tissues. In conclusion, our novel TRGs-based model has great predictive value for the prognosis of DLBCL patients and provides a promising direction for treatment optimization.

IRF8-mutant B cell lymphoma evades immunity through a CD74-dependent deregulation of antigen processing and presentation in MHC CII complexes

In diffuse large B-cell lymphoma (DLBCL), the transcription factor IRF8 is the target of a series of potentially oncogenic events, including, chromosomal translocation, focal amplification, and super-enhancer perturbations. IRF8 is also frequently mutant in DLBCL, but how these variants contribute to lymphomagenesis is unknown. We modeled IRF8 mutations in DLBCL and found that they did not meaningfully impact cell fitness. Instead, IRF8 mutants, mapping either to the DNA-binding domain (DBD) or c-terminal tail, displayed diminished transcription activity towards CIITA, a direct IRF8 target. In primary DLBCL, IRF8 mutations were mutually exclusive with mutations in genes involved in antigen presentation. Concordantly, expression of IRF8 mutants in murine B cell lymphomas uniformly suppressed CD4, but not CD8, activation elicited by antigen presentation. Unexpectedly, IRF8 mutation did not modify MHC CII expression on the cell surface, rather it downmodulated CD74 and HLA- DM, intracellular regulators of antigen peptide processing/loading in the MHC CII complex. These changes were functionally relevant as, in comparison to IRF8 WT, mice harboring IRF8 mutant lymphomas displayed a significantly higher tumor burden, in association with a substantial remodeling of the tumor microenvironment (TME), typified by depletion of CD4, CD8, Th1 and NK cells, and increase in T-regs and Tfh cells. Importantly, the clinical and immune phenotypes of IRF8-mutant lymphomas were rescued in vivo by ectopic expression of CD74. Deconvolution of bulk RNAseq data from primary human DLBCL recapitulated part of the immune remodeling detected in mice and pointed to depletion of dendritic cells as another feature of IRF8 mutant TME. We concluded that IRF8 mutations contribute to DLBCL biology by facilitating immune escape.

Histone regulator KAT2A acts as a potential biomarker related to tumor microenvironment and prognosis of diffuse large B cell lymphoma

BACKGROUND

Recent studies have indicated that epigenetic alterations contribute significantly to lymphoma pathogenesis. A type of epigenetic regulation known as histone acetylation plays a crucial role in transcriptional regulation in eukaryotic cells. Specifically, a significant effect of histone acetylation modifications on the abnormal progression and microenvironment of diffuse large B-cell lymphoma (DLBCL) has been observed.

METHODS

To provide insight into the significance of histone acetylation-related genes, we developed a HAscore model for analyzing histone acetylation patterns in DLBCL samples. Furthermore, KAT2A, a regulator of histone acetylation, was knocked down in DLBCL cell lines to investigate its role in proliferation, cell cycle, and apoptosis.

RESULTS

The HAscore model has been demonstrated to provide insight into the significance of these patterns, showing that patients with a low HAscore have distinct tumor immune microenvironments and poorer prognoses. Besides, KAT2A was identified as a potential biomarker related to immune infiltration and malignant pathways in DLBCL.

CONCLUSION

According to these findings, it is evident that the histone acetylation pattern score model is helpful in describing the immune status of DLBCL and that KAT2A may be used as a biomarker for its treatment.

A nomogram for predicting the rapid progression of diffuse large B-cell lymphoma established by combining baseline PET/CT total metabolic tumor volume, lesion diffusion, and TP53 mutations

OBJECTIVES

This study aimed to integrate positron emission tomography/computed tomography (PET/CT) metrics and genetic mutations to optimize the risk stratification for diffuse large B-cell lymphoma (DLBCL) patients.

METHODS

The data of 94 primary DLBCL patients with baseline PET/CT examination completed in the Shandong Cancer Hospital and Institute (Jinan, China) were analyzed to establish a training cohort. An independent cohort of 45 DLBCL patients with baseline PET/CT examination from other hospitals was established for external validation. The baseline total metabolic tumor volume (TMTV) and the largest distance between two lesions (Dmax) standardized by patient body surface area (SDmax) were calculated. The pretreatment pathological tissues of all patients were sequenced by a lymphopanel including 43 genes.

RESULTS

The optimal TMTV cutoff was 285.3 cm3 and the optimal SDmax cutoff was 0.135 m-1 . TP53 status was found as an independent predictive factor significantly affecting complete remission (p = 0.001). TMTV, SDmax, and TP53 status were the main factors of the nomogram and could stratify the patients into four distinct subgroups based on their predicted progression-free survival (PFS). The calibration curve demonstrated satisfactory agreement between the predicted and actual 1-year PFS of the patients. The receiver operating characteristic curves showed this nomogram based on PET/CT metrics and TP53 mutations had a better predictive ability than the clinic risk scores. Similar results were identified upon external validation.

CONCLUSIONS

The nomogram based on imaging factors and TP53 mutations could lead to a more accurate selection of DLBCL patients with rapid progression, to increase tailor therapy.

An MYC-Driven Vicious Circuit Is a Targetable Achilles' Heel in Lymphoma

SUMMARY

In this issue of Blood Cancer Discovery, Nakanishi et al. uncover a critical role for the elevated activity of the translation initiation factor eIF5A in the malignant growth of MYC-driven lymphoma. eIF5A is posttranslationally modified by hypusination through MYC oncoprotein-mediated hyperactivation of the polyamine-hypusine circuit, which may represent a promising therapeutic target because an enzyme of this circuit that is required for hypusinating eIF5A proved to be essential for lymphoma development. See related article by Nakanishi et al., p. 294 (4).

Progression of follicular lymphoma and related entities: Report from the 2021 SH/EAHP Workshop

OBJECTIVES

The 2021 Society for Hematopathology and European Association for Haematopathology Workshop addressed the molecular and cytogenetic underpinnings of transformation and transdifferentiation in lymphoid neoplasms.

METHODS

Session 4, "Transformations of Follicular Lymphoma," and session 5, "Transformations of Other B-Cell Lymphomas," included 45 cases. Gene alteration analysis and expression profiling were performed on cases with submitted formalin-fixed, paraffin embedded tissue.

RESULTS

The findings from session 4 suggest that "diffuse large B-cell lymphoma/high-grade B-cell lymphoma with rearrangements of MYC and BCL2" is a distinct category arising from the constraints of a preexisting BCL2 translocation. TdT expression in aggressive B-cell lymphomas is associated with MYC rearrangements, immunophenotypic immaturity, and a dismal prognosis but must be differentiated from lymphoblastic -lymphoma. Cases in session 5 illustrated unusual morphologic and immunophenotypic patterns of transformation. Additionally, the findings support the role of cytogenetic abnormalities-specifically, MYC and NOTCH1 rearrangements-as well as single gene alterations, including TP53, in transformation.

CONCLUSIONS

Together, these unique cases and their accompanying molecular and cytogenetic data suggest potential mechanisms for and unusual patterns of transformation in B-cell lymphomas and indicate numerous opportunities for further study.

Integration analysis of tumor metagenome and peripheral immunity data of diffuse large-B cell lymphoma

Background/purpose

It has been demonstrated that gut microbes are closely associated with the pathogenesis of lymphoma, but the gut microbe landscape and its association with immune cells in diffuse large B-cell lymphoma (DLBCL) remain largely unknown. In this study, we explored the associations between gut microbiota, clinical features and peripheral blood immune cell subtypes in DLBCL.

Method

A total of 87 newly diagnosed DLBCL adults were enrolled in this study. The peripheral blood samples were collected from all patients and then submitted to immune cell subtyping using full-spectral flow cytometry. Metagenomic sequencing was applied to assess the microbiota landscape of 69 of 87 newly diagnosed DLBCL patients. The microbiotas and peripheral blood immune cell subsets with significant differences between different National Comprehensive Center Network-International Prognostic Indexes (NCCN-IPIs) (low-risk, low-intermediate-risk, intermediate-high-risk, high-risk) groups were screened.

Results

A total of 10 bacterial phyla, 31 orders and 455 bacteria species were identified in 69 patients with newly diagnosed DLBCL. The abundances of 6 bacteria, including Blautia sp.CAG 257, Actinomyces sp.S6 Spd3, Streptococcus parasanguinis, Bacteroides salyersiae, Enterococcus faecalls and Streptococcus salivarius were significantly different between the low-risk, low-intermediate-risk, intermediate-high-risk and high-risk groups, among which Streptococcus parasanguinis and Streptococcus salivarius were markedly accumulated in the high-risk group. The different bacteria species were mostly enriched in the Pyridoxal 5'-phosphate biosynthesis I pathway. In addition, we found that 2 of the 6 bacteria showed close associations with the different immune cell subtypes which were also identified from different NCCN-IPIs. In detail, the abundance of Bacteroides salyersiae was negatively correlated with Treg cells, CD38+ nonrescue exhausted T cells, nature killer 3 cells and CD38+CD8+ effector memory T cells, while the abundance of Streptococcus parasanguinis was negatively correlated with HLA-DR+ NK cells, CD4+ Treg cells, HLA-DR+ NKT cells and HLA-DR+CD94+CD159c+ NKT cells.

Conclusion

This study first reveals the gut microbiota landscape of patients with newly diagnosed DLBCL and highlights the association between the gut microbiota and immunity, which may provide a new idea for the prognosis assessment and treatment of DLBCL.

Modulation of T-cell function by myeloid-derived suppressor cells in hematological malignancies

Myeloid-derived suppressor cells (MDSCs) are pathologically activated neutrophils and monocytes that negatively regulate the immune response to cancer and chronic infections. Abnormal myelopoiesis and pathological activation of myeloid cells generate this heterogeneous population of myeloid-derived suppressor cells. They are characterized by their distinct transcription, phenotypic, biochemical, and functional features. In the tumor microenvironment (TME), myeloid-derived suppressor cells represent an important class of immunosuppressive cells that correlate with tumor burden, stage, and a poor prognosis. Myeloid-derived suppressor cells exert a strong immunosuppressive effect on T-cells (and a broad range of other immune cells), by blocking lymphocyte homing, increasing production of reactive oxygen and nitrogen species, promoting secretion of various cytokines, chemokines, and immune regulatory molecules, stimulation of other immunosuppressive cells, depletion of various metabolites, and upregulation of immune checkpoint molecules. Additionally, the heterogeneity of myeloid-derived suppressor cells in cancer makes their identification challenging. Overall, they serve as a major obstacle for many cancer immunotherapies and targeting them could be a favorable strategy to improve the effectiveness of immunotherapeutic interventions. However, in hematological malignancies, particularly B-cell malignancies, the clinical outcomes of targeting these myeloid-derived suppressor cells is a field that is still to be explored. This review summarizes the complex biology of myeloid-derived suppressor cells with an emphasis on the immunosuppressive pathways used by myeloid-derived suppressor cells to modulate T-cell function in hematological malignancies. In addition, we describe the challenges, therapeutic strategies, and clinical relevance of targeting myeloid-derived suppressor cells in these diseases.

Venetoclax improves CD20 immunotherapy in a mouse model of MYC/BCL2 double-expressor diffuse large B-cell lymphoma

BACKGROUND

Approximately one-third of diffuse large B cell lymphoma (DLBCL) patients exhibit co-expression of MYC and BCL2 (double-expressor lymphoma, DEL) and have a dismal prognosis. Targeted inhibition of the anti-apoptotic protein BCL2 with venetoclax (ABT-199) has been approved in multiple B-cell malignancies and is currently being investigated in clinical trials for DLBCL. Whether BCL2 anti-apoptotic function represents a multifaceted vulnerability for DEL-DLBCL, affecting both lymphoma B cells and T cells within the tumor microenvironment, remains to be elucidated.

METHODS

Here, we present novel genetically engineered mice that preclinically recapitulate DEL-DLBCL lymphomagenesis, and evaluate their sensitivity ex vivo and in vivo to the promising combination of venetoclax with anti-CD20-based standard immunotherapy.

RESULTS

Venetoclax treatment demonstrated specific killing of MYC⁺/BCL2⁺ lymphoma cells by licensing their intrinsically primed apoptosis, and showed previously unrecognized immunomodulatory activity by specifically enriching antigen-activated effector CD8 T cells infiltrating the tumors. Whereas DEL-DLBCL mice were refractory to venetoclax alone, inhibition of BCL2 significantly extended overall survival of mice that were simultaneously treated with a murine surrogate for anti-CD20 rituximab.

CONCLUSIONS

These results suggest that the combination of anti-CD20-based immunotherapy and BCL2 inhibition leads to cooperative immunomodulatory effects and improved preclinical responses, which may offer promising therapeutic opportunities for DEL-DLBCL patients.

The FACT-targeted drug CBL0137 enhances the effects of rituximab to inhibit B-cell non-Hodgkin's lymphoma tumor growth by promoting apoptosis and autophagy

BACKGROUND

Aggressive B-cell non-Hodgkin's lymphoma (B-NHL) patients often develop drug resistance and tumor recurrence after conventional immunochemotherapy, for which new treatments are needed.

METHODS

We investigated the antitumor effects of CBL0137. In vitro, cell proliferation was assessed by CCK-8 and colony formation assay. Flow cytometry was performed to analyze cell cycle progression, apoptosis, mitochondrial depolarization, and reactive oxygen species (ROS) production. Autophagy was detected by transmission electron microscopy and mGFP-RFP-LC3 assay, while western blotting was employed to detect proteins involved in apoptosis and autophagy. RNA-sequencing was conducted to analyze the transcription perturbation after CBL0137 treatment in B-NHL cell lines. Finally, the efficacy and safety of CBL0137, rituximab, and their combination were tested in vivo.

RESULTS

CBL0137, a small molecule anticancer agent that has significant antitumor effects in B-NHL. CBL0137 sequesters the FACT (facilitates chromatin transcription) complex from chromatin to produce cytotoxic effects in B-NHL cells. In addition, we discovered novel anticancer mechanisms of CBL0137. CBL0137 inhibited human B-NHL cell proliferation by inducing cell cycle arrest in S phase via the c-MYC/p53/p21 pathway. Furthermore, CBL0137 triggers ROS generation and induces apoptosis and autophagy in B-NHL cells through the ROS-mediated PI3K/Akt/mTOR and MAPK signaling pathways. Notably, a combination of CBL0137 and rituximab significantly suppressed B-NHL tumor growth in subcutaneous models, consistent with results at the cellular level in vitro.

CONCLUSIONS

CBL0137 has potential as a novel approach for aggressive B-NHL, and its combination with rituximab can provide new therapeutic options for patients with aggressive B-NHL. Video Abstract.

Clinicopathological Characteristics and Prognosis of Diffuse Large B-Cell Lymphoma in Relation to CA-125 and CA 19-9 Expression

Background: Some epithelial tumors express the carbohydrate antigen 125 (Cancer antigen-125, CA-125) and CA 19-9, especially ovarian and pancreatic tumors. Patients with non-Hodgkin lymphoma (NHL) were reported to have a close association between serum CA-125 levels and adverse prognostic factors with worse survival. We aimed to investigate CA-125 and 19-9 expression in nodal diffuse large B-cell lymphoma, not otherwise specified (DLBCL NOS) tissues using immunohistochemistry (IHC) and their relations to clinicopathological manifestations and patients' survival. Methods: 65 cases of DLBCL NOS were examined. A modified mechanical pencil tip was used to construct Manual Tissue Micro-array (TMA) blocks. Immunohistochemical staining for CA-125 and CA 19-9 was performed and scored semi-quantitatively. All relations were analyzed using established statistical methodologies. Results: Aberrant expression of CA 19-9 was detected in 12% of cases without any expression of CA-125. Moreover, 75% of the CA 19-9 positive cases were statistically significantly associated with anemia and performance status 1. Also, 75% of the CA 19-9 positive cases were females. Conclusions: CA 19-9 was aberrantly expressed in 12% of nodal DLBCL NOS cases and significantly related to anaemia and performance status but not to survival. In cases of DLBCL NOS, CA 19-9 expression cannot be considered an independent prognostic factor. CA-125 was not expressed in nodal DLBCL NOS tissues, necessitating re-evaluation studies. Therefore, it is advised to conduct more research to clarify the potential correlation between serum and tissue CA 19-9 levels and other clinic-pathological characteristics of nodal and extranodal DLBCL NOS patients.

Impact of C-reactive protein and albumin levels on short, medium, and long term mortality in patients with diffuse large B-cell lymphoma

Objectives and study design: In this population-based study of 602 patients, we amended C-reactive protein (CRP) and plasma albumin (PA) levels around the diagnosis of diffuse large B-cell lymphoma (DLBCL) to the International Prognostic Index (IPI) and assessed 0-90, 91-365, and +365-day survival.Results: The CRP did not contribute to the IPI's prognostic or discriminatory ability, regardless of time period, particularly not in models with PA. In contrast, the PA was an important contributor, especially in the 0-90 day period, but also up to one year after the diagnosis. For day 0-90, the model with the IPI only had an Area Under the Receiver Operating Characteristics (AUROC) of 0.742, whereas the IPI with PA as a continuous variable rendered an AUROC of 0.841. Especially the lower PA quartile (18-32 g/L) contributed to the worse prognosis.Conclusions: The amendment of PA to the IPI may significantly improve the short-term prognostic and discriminative ability.Key messagesThe amendment of the plasma albumin (PA) level to the International Prognostic Index significantly improved the prediction of mortality up to one year after the diagnosis of diffuse large B-cell lymphoma.It was especially the lower quartile of the PA level (18-32 g/L) that contributed to the worse prognosis.

The path towards consensus genome classification of diffuse large B-cell lymphoma for use in clinical practice

Diffuse large B-cell lymphoma (DLBCL) is a widely heterogeneous disease in presentation, treatment response and outcome that results from a broad biological heterogeneity. Various stratification approaches have been proposed over time but failed to sufficiently capture the heterogeneous biology and behavior of the disease in a clinically relevant manner. The most recent DNA-based genomic subtyping studies are a major step forward by offering a level of refinement that could serve as a basis for exploration of personalized and targeted treatment for the years to come. To enable consistent trial designs and allow meaningful comparisons between studies, harmonization of the currently available knowledge into a single genomic classification widely applicable in daily practice is pivotal. In this review, we investigate potential avenues for harmonization of the presently available genomic subtypes of DLBCL inspired by consensus molecular classifications achieved for other malignancies. Finally, suggestions for laboratory techniques and infrastructure required for successful clinical implementation are described.

Biological and clinical significance of epigenetic alterations in B-cell lymphomas

Recent advances in genetic analysis of hematopoietic tumors have led to the discovery of enzyme abnormalities that control epigenetic changes. Notably, genetic mutations associated with DNA methylation and histone modifications have been identified in B-cell malignant lymphomas, including diffuse large B-cell lymphoma and follicular lymphoma. Gene expression involved in B lymphocyte differentiation and maturation within the germinal center (GC) is regulated epigenetically in these lymphomas, and epigenetic alterations play critical roles in the pathogenesis of GC-driven lymphomas. Recent studies also indicate the importance of epigenetic alterations as biomarkers and therapeutic targets, suggesting that they will have a central role in developing precision medicine for patients with GC-driven lymphomas.

Cyclic-AMP signalling, MYC and hypoxia-inducible factor 1α intersect to regulate angiogenesis in B-cell lymphoma

Angiogenesis and MYC expression associate with poor outcome in diffuse large B-cell lymphoma (DLBCL). MYC promotes neo-vasculature development but whether its deregulation in DLBCL contributes to angiogenesis is unclear. Examination of this relationship may uncover novel pathogenic regulatory circuitry as well as anti-angiogenic strategies in DLBCL. Here, we show that MYC expression positively correlates with vascular endothelial growth factor (VEGF) expression and angiogenesis in primary DLBCL biopsies, independently of dual expressor status or cell-of-origin classification. We found that MYC promotes VEGFA expression, a correlation that was validated in large datasets of mature B-cell tumours. Using DLBCL cell lines and patient-derived xenograft models, we identified the second messenger cyclic-AMP (cAMP) as a potent suppressor of MYC expression, VEGFA secretion and angiogenesis in DLBCL in normoxia. In hypoxia, cAMP switched targets and suppressed hypoxia-inducible factor 1α, a master regulator of VEGFA/angiogenesis in low oxygen environments. Lastly, we used the phosphodiesterase 4b (Pde4b) knockout mouse to demonstrate that the cAMP/PDE4 axis exercises additional anti-angiogenesis by directly targeting the lymphoma microenvironment. In conclusion, MYC could play a direct role in DLBCL angiogenesis, and modulation of cAMP levels, which can be achieved with clinical grade PDE4 inhibitors, has cell and non-cell autonomous anti-angiogenic activity in DLBCL.

Advances in the Study of circRNAs in Hematological Malignancies

Circular RNAs (circRNAs) are non–protein-coding RNAs that have a circular structure and do not possess a 5` cap or 3` poly-A tail. Their structure is more stable than that of linear RNAs, and they are difficult to deform via hydrolysis. Advancements in measurement technology such as RNA sequencing have enabled the detection of circRNAs in various eukaryotes in both in vitro and in vivo studies. The main function of circRNAs involves sponging of microRNAs (MiRNAs) and interaction with proteins associated with physiological and pathological processes, while some circRNAs are involved in translation. circRNAs act as tumor suppressors or oncogenes during the development of many tumors and are emerging as new diagnostic and prognostic biomarkers. They also affect resistance to certain chemotherapy drugs such as imatinib. The objective of this review is to investigate the expression and clinical significance of circRNAs in hematological malignancies. We will also explore the effect of circRNAs on proliferation and apoptosis in hematological malignancy cells and their possible use as biomarkers or targets to determine prognoses. The current literature indicates that circRNAs may provide new therapeutic strategies for patients with hematologic malignancies.

Molecular Diagnostic Review of Diffuse Large B-Cell Lymphoma and Its Tumor Microenvironment

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma. It is a clinically and morphologically heterogeneous entity that has continued to resist complete subtyping. Molecular subtyping efforts emerged in earnest with the advent of gene expression profiling (GEP). This molecular subtyping approach has continued to evolve simultaneously with others including immunohistochemistry and more modern genomic approaches. Recently, the veritable explosion of genomic data availability and evolving computational methodologies have provided additional avenues, by which further understanding and subclassification of DBLCLs is possible. The goal of this review is to provide a historical overview of the major classification timepoints in the molecular subtyping of DLBCL, from gene expression profiling to present day understanding.

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.

Identification of molecular subtypes and a novel prognostic model of diffuse large B-cell lymphoma based on a metabolism-associated gene signature

Background

Diffuse large B cell lymphoma (DLBCL) is the most common lymphoma in adults. Metabolic reprogramming in tumors is closely related to the immune microenvironment. This study aimed to explore the interactions between metabolism-associated genes (MAGs) and DLBCL prognosis and their potential associations with the immune microenvironment.

Methods

Gene expression and clinical data on DLBCL patients were obtained from the GEO database. Metabolism-associated molecular subtypes were identified by consensus clustering. A prognostic risk model containing 14 MAGs was established using Lasso-Cox regression in the GEO training cohort. It was then validated in the GEO internal testing cohort and TCGA external validation cohort. GO, KEGG and GSVA were used to explore the differences in enriched pathways between high- and low-risk groups. ESTIMATE, CIBERSORT, and ssGSEA analyses were used to assess the immune microenvironment. Finally, WGCNA analysis was used to identify two hub genes among the 14 model MAGs, and they were preliminarily verified in our tissue microarray (TMA) using multiple fluorescence immunohistochemistry (mIHC).

Results

Consensus clustering divided DLBCL patients into two metabolic subtypes with significant differences in prognosis and the immune microenvironment. Poor prognosis was associated with an immunosuppressive microenvironment. A prognostic risk model was constructed based on 14 MAGs and it was used to classify the patients into two risk groups; the high-risk group had poorer prognosis and an immunosuppressive microenvironment characterized by low immune score, low immune status, high abundance of immunosuppressive cells, and high expression of immune checkpoints. Cox regression, ROC curve analysis, and a nomogram indicated that the risk model was an independent prognostic factor and had a better prognostic value than the International Prognostic Index (IPI) score. The risk model underwent multiple validations and the verification of the two hub genes in TMA indicated consistent results with the bioinformatics analyses.

Conclusions

The molecular subtypes and a risk model based on MAGs proposed in our study are both promising prognostic classifications in DLBCL, which may provide novel insights for developing accurate targeted cancer therapies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03393-9.

Therapeutic targeting miR130b counteracts diffuse large B-cell lymphoma progression via OX40/OX40L-mediated interaction with Th17 cells

MicroRNAs (miRNAs) are involved in lymphoma progression by regulating the tumor microenvironment. Serum miR130b is overexpressed in diffuse large B-cell lymphoma (DLBCL), inducing Th17 cell alterations. To further illustrate its biological significance and therapeutic rationale, miR130b was detected by quantitative real-time PCR in the serum samples of 532 newly diagnosed DLBCL patients. The mechanism of miR130b on lymphoma progression and the tumor microenvironment was investigated both in vitro and in vivo. Therapeutic targeting miR130b was also evaluated, including OX40 agonistic antibody and lipid nanoparticles (LNPs)-miR130b antagomir. The results showed that serum miR130b significantly correlated with tumor miR130b and serum interleukin-17, indicating lymphoma relapse and inferior survival of DLBCL patients. MiR130b overexpression altered tumor microenvironment signaling pathways and increased Th17 cell activity. As mechanism of action, miR130b downregulated tumor OX40L expression by directly targeting IFNAR1/p-STAT1 axis, recruiting Th17 cells via OX40/OX40L interaction, thereby promoting immunosuppressive function of Th17 cells. In co-culture systems of B-lymphoma cells with immune cells, miR130b inhibited lymphoma cell autophagy, which could be counteracted by OX40 agonistic antibody and LNPs-miR130b antagomir. In murine xenograft model established with subcutaneous injection of A20 cells, both OX40 agonistic antibody and LNPs-miR130b antagomir remarkably inhibited Th17 cells and retarded miR130b-overexpressing tumor growth. In conclusion, as an oncogenic biomarker of DLBCL, miR130b was related to lymphoma progression through modulating OX40/OX40L-mediated lymphoma cell interaction with Th17 cells, attributing to B-cell lymphoma sensitivity towards OX40 agonistic antibody. Targeting miR130b using LNPs-miR130b antagomir could also be a potential immunotherapeutic strategy in treating OX40-altered lymphoid malignancies.

Reproducibility of Gene Expression Signatures in Diffuse Large B-Cell Lymphoma

Multiple gene expression profiles have been identified in diffuse large B-cell lymphoma (DLBCL). Besides the cell of origin (COO) classifier, no signatures have been reproduced in independent studies or evaluated for capturing distinct aspects of DLBCL biology. We reproduced 4 signatures in 175 samples of the HOVON-84 trial on a panel of 117 genes using the NanoString platform. The four gene signatures capture the COO, MYC activity, B-cell receptor signaling, oxidative phosphorylation, and immune response. Performance of our classification algorithms were confirmed in the original datasets. We were able to validate three of the four GEP signatures. The COO algorithm resulted in 94 (54%) germinal center B-cell (GCB) type, 58 (33%) activated B-cell (ABC) type, and 23 (13%) unclassified cases. The MYC-classifier revealed 77 cases with a high MYC-activity score (44%) and this MYC-high signature was observed more frequently in ABC as compared to GCB DLBCL (68% vs. 32%, p < 0.00001). The host response (HR) signature of the consensus clustering was present in 55 (31%) patients, while the B-cell receptor signaling, and oxidative phosphorylation clusters could not be reproduced. The overlap of COO, consensus cluster and MYC activity score differentiated six gene expression clusters: GCB/MYC-high (12%), GCB/HR (16%), GCB/non-HR (27%), COO-Unclassified (13%), ABC/MYC-high (25%), and ABC/MYC-low (7%). In conclusion, the three validated signatures identify distinct subgroups based on different aspects of DLBCL biology, emphasizing that each classifier captures distinct molecular profiles.

Diffuse large B-cell lymphomas in adults with aberrant coexpression of CD10, BCL6, and MUM1 are enriched in IRF4 rearrangements

DLBCL in adults aberrantly coexpressing CD10, BCL6, and MUM1 is genetically heterogeneous and enriched in IRF4-rearranged cases.

IRF4-rearranged DLBCL in adults share genetic features with LBCL-IRF4 in children but with higher genomic complexity and often ABC GEP.

Diffuse large B-cell lymphoma (DLBCL) with aberrant coexpression of CD10⁺BCL6⁺MUM1⁺ (DLBCL-AE), classified as germinal center B cell (GCB) type by the Hans algorithm (HA), was genetically characterized. To capture the complexity of DLBCL-AE, we used an integrated approach that included gene expression profiling (GEP), fluorescence in situ hybridization, targeted gene sequencing, and copy number (CN) arrays. According to GEP, 32/54 (59%) cases were classified as GCB-DLBCL, 16/54 (30%) as activated B-cell (ABC) DLBCL, and 6/54 (11%) as unclassifiable. The discrepancy between HA and GEP was 41%. Three genetic subgroups were identified. Group 1 included 13/50 (26%) cases without translocations and mainly showing and ABC/MCD molecular profile. Group 2 comprised 11/50 (22%) cases with IRF4 alterations (DLBCL-IRF4), frequent mutations in IRF4 (82%) and NF-κB pathway genes (MYD88, CARD11, and CD79B), and losses of 17p13.2. Five cases each were classified as GCB- or ABC-type. Group 3 included 26/50 (52%) cases with 1 or several translocations in BCL2/BCL6/MYC/IGH, and GCB/EZB molecular profile predominated. Two cases in this latter group showed complex BCL2/BCL6/IRF4 translocations. DLBCL-IRF4 in adults showed a similar copy number profile and shared recurrent CARD11 and CD79B mutations when compared with LBCL-IRF4 in the pediatric population. However, adult cases showed higher genetic complexity, higher mutational load with frequent MYD88 and KMT2D mutations, and more ABC GEP. IRF4 mutations were identified only in IRF4-rearranged cases, indicating its potential use in the diagnostic setting. In conclusion, DLBCL-AE is genetically heterogeneous and enriched in cases with IRF4 alterations. DLBCL-IRF4 in adults has many similarities to the pediatric counterpart.

Potency Meets Precision in Nano-optimized Chemotherapeutics

Chemotherapy remains the most widely used cancer treatment modality. Nanotechnology provides exciting opportunities to improve these drugs, transforming decades-old generic treatments into precise new medicines. We illustrate the potential of recent advances in nanotechnology-enhanced therapy focusing on diffuse large B-cell lymphoma (DLBCL); the most common hematologic malignancy.

The biology of the tumor microenvironment in DLBCL: Targeting the "don't eat me" signal

Diffuse large B-cell lymphoma (DLBCL) is the most common type of malignant lymphoma with biologically and clinically heterogeneous features. Recently, the tumor microenvironment of this disease has been recognized as an important biological aspect of tumor development and therapeutic targets. Recurrent genetic alterations play significant roles in immune recognition of lymphoma cells. In particular, novel genetic alterations promoting phagocytosis were identified, suggesting a potential therapeutic strategy targeting the “don’t eat me” signal.

Targeting the tumor microenvironment in B-cell lymphoma: challenges and opportunities

B-cell lymphoma is a group of hematological malignancies with high clinical and biological heterogeneity. The pathogenesis of B-cell lymphoma involves a complex interaction between tumor cells and the tumor microenvironment (TME), which is composed of stromal cells and extracellular matrix. Although the roles of the TME have not been fully elucidated, accumulating evidence implies that TME is closely relevant to the origination, invasion and metastasis of B-cell lymphoma. Explorations of the TME provide distinctive insights for cancer therapy. Here, we epitomize the recent advances of TME in B-cell lymphoma and discuss its function in tumor progression and immune escape. In addition, the potential clinical value of targeting TME in B-cell lymphoma is highlighted, which is expected to pave the way for novel therapeutic strategies.

Treatment resistance in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is a highly heterogeneous disease and represents the most common subtype of lymphoma. Although 60-70% of all patients can be cured by the current standard of care in the frontline setting, the majority of the remaining patients will experience treatment resistance and have a poor clinical outcome. Numerous efforts have been made to improve the efficacy of the standard regimen by, for example, dose intensification or adding novel agents. However, these results generally failed to demonstrate significant clinical benefits. Hence, understanding treatment resistance is a pressing need to optimize the outcome of those patients. In this Review, we first describe the conceptual sources of treatment resistance in DLBCL and then provide detailed and up-to-date molecular insight into the mechanisms of resistance to the current treatment options in DLBCL. We lastly highlight the potential strategies for rationally managing treatment resistance from both the preventive and interventional perspectives.

Fluorescent nanoparticle-mediated semiquantitative MYC protein expression analysis in morphologically diffuse large B-cell lymphoma

The current World Health Organization (WHO) classification defines a new disease entity of high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements, making fluorescence in situ hybridization (FISH) screening for these genes mandatory. In addition, the prognostic significance of MYC expression was reported, with a cut-off value of 40%. However, interobserver discrepancies arise due to the heterogeneous intensity of MYC expression by immunohistochemistry. Moreover, a cut-off value of positivity for MYC protein in diffuse large B-cell lymphoma (DLBCL) varies among studies at present. Here, we applied a high-sensitivity semiquantitative immunohistochemical technique using fluorescent nanoparticles called phosphor-integrated dots (PID) to evaluate the MYC expression in 50 de novo DLBCL cases, and compared it with the conventional diaminobenzidine (DAB)-developing system. The high MYC expression detected by the PID-mediated system predicted poor overall survival in DLBCL patients. However, we found no prognostic value of MYC protein expression for any cut-off value by the DAB-developing system, even if the intensity was considered. These results indicate that the precise evaluation of MYC protein expression can clarify the prognostic values in DLBCL, irrespective of MYC rearrangement.

Comprehensive Characterization of Cachexia-Inducing Factors in Diffuse Large B-Cell Lymphoma Reveals a Molecular Subtype and a Prognosis-Related Signature

Background

Cachexia is defined as an involuntary decrease in body weight, which can increase the risk of death in cancer patients and reduce the quality of life. Cachexia-inducing factors (CIFs) have been reported in colorectal cancer and pancreatic adenocarcinoma, but their value in diffuse large B-cell lymphoma (DLBCL) requires further genetic research.

Methods

We used gene expression data from Gene Expression Omnibus to evaluate the expression landscape of 25 known CIFs in DLBCL patients and compared them with normal lymphoma tissues from two cohorts [GSE56315 (n = 88) and GSE12195 (n = 136)]. The mutational status of CIFs were also evaluated in The Cancer Genome Atlas database. Based on the expression profiles of 25 CIFs, a single exploratory dataset which was merged by the datasets of GSE10846 (n = 420) and GSE31312 (n = 498) were divided into two molecular subtypes by using the method of consensus clustering. Immune microenvironment between different subtypes were assessed via single-sample gene set enrichment analysis and the CIBERSORT algorithm. The treatment response of commonly used chemotherapeutic drugs was predicted and gene set variation analysis was utilized to reveal the divergence in activated pathways for distinct subtypes. A risk signature was derived by univariate Cox regression and LASSO regression in the merged dataset (n = 882), and two independent cohorts [GSE87371 (n = 221) and GSE32918 (n = 244)] were used for validation, respectively.

Results

Clustering analysis with CIFs further divided the cases into two molecular subtypes (cluster A and cluster B) associated with distinct prognosis, immunological landscape, chemosensitivity, and biological process. A risk-prognostic signature based on CCL2, CSF2, IL15, IL17A, IL4, TGFA, and TNFSF10 for DLBCL was developed, and significant differences in overall survival analysis were found between the low- and high-risk groups in the training dataset and another two independent validation datasets. Multivariate regression showed that the risk signature was an independently prognostic factor in contrast to other clinical characteristics.

Conclusion

This study demonstrated that CIFs further contribute to the observed heterogeneity of DLBCL, and molecular classification and a risk signature based on CIFs are both promising tools for prognostic stratification, which may provide important clues for precision medicine and tumor-targeted therapy.