Development Of B-cell Lymphoma Research Articles

Compensatory reactions of B cells in response to chronic HIV-1 Tat exposure.

Patients infected with human immunodeficiency virus-1 (HIV-1) have an increased incidence of B-cell lymphoma, even though HIV-1 does not infect B cells. The development of B-cell lymphomas appears to be related to the action of the HIV-1 transactivator protein (Tat), which is released from HIV-infected cells and penetrates uninfected B cells, affecting host cell gene expression. Upon chronic HIV-1 infection, Tat acts on the cells for a long time, probably allowing the cells to adapt to the presence of the viral protein. The aim of this work was to identify and study the mechanism of adaptation of cells to prolonged (chronic) exposure to HIV-1 Tat. We performed a comparative analysis of cells expressing Tat under the action of either an inducible promoter or a constitutive promoter, allowing us to model acute and chronic Tat effects, respectively. We found that the acute action of Tat leads to the suppression of cell proliferation, probably due to the downregulation of genes associated with replication and protein synthesis. In the case of chronic action of Tat, cell proliferation was restored and the expression of genes associated with the implementation of protective (antiviral) functions of the cell was increased. Analysis using proteasome inhibitors showed that in the case of chronic action, intense Tat proteolysis occurred, which could be the main mechanism of B-cell adaptation. Thus, B cells have a powerful mechanism to adapt to the entry of HIV-1 Tat, the efficiency of which may determine the frequency of lymphomagenesis in HIV-1-infected patients.

Decreased PU.1 expression in mature B cells induces lymphomagenesis.

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of lymphoma, accounting for 30% of non-Hodgkin lymphomas. Although comprehensive analysis of genetic abnormalities has led to the classification of lymphomas, the exact mechanism of lymphomagenesis remains elusive. The Ets family transcription factor, PU.1, encoded by Spi1, is essential for the development of myeloid and lymphoid cells. Our previous research illustrated the tumor suppressor function of PU.1 in classical Hodgkin lymphoma and myeloma cells. In the current study, we found that patients with DLBCL exhibited notably reduced PU.1 expression in their lymphoma cells, particularly in the non-germinal center B-cell-like (GCB) subtype. This observation suggests that downregulation of PU.1 may be implicated in DLBCL tumor growth. To further assess PU.1's role in mature B cells invivo, we generated conditional Spi1 knockout mice using Cγ1-Cre mice. Remarkably, 13 of the 23 knockout mice (56%) showed splenomegaly, lymphadenopathy, or masses, with some having histologically confirmed B-cell lymphomas. In contrast, no wild-type mice developed B-cell lymphoma. In addition, RNA-seq analysis of lymphoma cells from Cγ1-Cre Spi1F/F mice showed high frequency of each monoclonal CDR3 sequence, indicating that these lymphoma cells were monoclonal tumor cells. When these B lymphoma cells were transplanted into immunodeficient recipient mice, all mice died within 3 weeks. Lentiviral-transduced Spi1 rescued 60% of the recipient mice, suggesting that PU.1 has a tumor suppressor function invivo. Collectively, PU.1 is a tumor suppressor in mature B cells, and decreased PU.1 results in mature B-cell lymphoma development.

Integrated multi-omics profiling reveals the ZZZ3/CD70 axis is a super-enhancer-driven regulator of diffuse large B-cell lymphoma cell-natural killer cell interactions.

Tumor immune microenvironment is crucial for diffuse large B-cell lymphoma (DLBCL) development. However, the mechanisms by which super-enhancers (SEs) regulate the interactions between DLBCL cells and tumor-infiltrating immune cells remains largely unknown. This study aimed to investigate the role of SE-controlled genes in regulating the interactions between DLBCL cells and tumor-infiltrating immune cells. Single-cell RNA-seq, bulk RNA-seq and H3K27ac ChIP-seq data were downloaded from the Heidelberg Open Research Data database and Gene Expression Omnibus database. HOMER algorithm and Seurat package in R were used for bioinformatics analysis. Cell proliferation and lactate dehydrogenase (LDH) release was detected by MTS and LDH release assays, respectively. Interaction between B cell cluster and CD8+ T cell and NK cell cluster was most obviously enhanced in DLBCL, with CD70-CD27, MIF-CD74/CXCR2 complex, MIF-CD74/CD44 complex and CCL3-CCR5 interactions were significantly increased. NK cell sub-cluster showed the strongest interaction with B cell cluster. ZZZ3 upregulated the transcription of CD70 by binding to its SE. Silencing CD70 in DOHH2 cells significantly promoted the proliferation of co-cultured NK92 cells and LDH release from DOHH2 cells, which was counteracted by ZZZ3 overexpression in DOHH2 cells. CD70 silencing combined with PD-L1 blockade promoted LDH release from DOHH2 cells co-cultured with NK92 cells. In conclusion, DLBCL cells inhibited the proliferation and killing of infiltrating NK cells by regulating ZZZ3/CD70 axis. Targeting ZZZ3/CD70 axis combined with PD-L1 blockade is expected to be a promising strategy for DLBCL treatment.

Transcriptomics explores potential mechanisms for the development of Primary Sjogren’s syndrome to diffuse large B-cell lymphoma in B cells

PurposePrimary Sjogren's syndrome (pSS) is a prevalent autoimmune disease. The immune dysregulation it causes often leads to the development of diffuse large B-cell lymphoma (DLBCL) in clinical practice. However, how it contributes to these two disorders at the molecular level is not yet known. This study explored the potential molecular mechanisms associated with the differences between DLBCL and pSS.Patients and methodsGene expression matrices from discovery cohort 1, discovery cohort 2, and the validation cohort were downloaded from the GEO and TCGA databases. Weighted gene coexpression network analysis (WGCNA) was performed to identify the coexpression modules of DLBCL and pSS in discovery cohort 1 and obtain shared genes. GO and KEGG enrichment analyses and PPI network analysis were performed on the shared genes. Immune-related genes (IRGs) were intersected with shared genes to obtain common genes. Afterward, common genes were identified via machine learning methods. The immune infiltration analysis, miRNA-TF-hub gene regulatory chart, gene interactions of the hub genes, and gene‒drug target analysis were performed. Finally, STAT1 was identified as a possible essential gene by the above analysis, and immune infiltration and GSEA pathway analyses were performed in the high- and low-expression groups in discovery cohort 2. The diagnostic efficacy of the hub genes was assessed in the validation cohort, and clinical samples were collected for validation.ResultsBy WGCNA, one modular gene in each group was considered highly associated with the disease, and we obtained 28 shared genes. Enrichment analysis revealed shared genes involved in the viral response and regulation. We obtained four hub genes (ISG20, STAT1, TLR7, and RSAD2) via the algorithm. Hub genes and similar genes are primarily involved in regulating type I IFNs. The construction of a miRNA-TF-hub gene regulatory chart revealed that hsa-mir-155-5p, hsa-mir-146b-5p, hsa-mir-21-3p, and hsa-mir-126-3p play essential roles in both diseases. Hub genes were differentially expressed in B-cell memory according to immune infiltration analysis. Hub genes had a strong diagnostic effect on both diseases. STAT1 plays an essential role in immune cells in both diseases.ConclusionWe identified hub susceptibility genes for DLBCL and pSS and identified hub genes and potential therapeutic targets that may act as biomarkers.

Palmitic acid reduces the methylation of the FOXO1 promoter to suppress the development of diffuse large B-cell lymphoma via modulating the miR-429/DNMT3A axis

Diffuse large B-cell lymphoma (DLBCL) is characterized by significant treatment resistance. Palmitic acid (PA) has shown promising antitumor properties. This study aims to elucidate the molecular mechanisms by which PA influences DLBCL progression. We quantified the expression levels of microRNAs (miRNAs), Forkhead box protein O1 (FOXO1), and DNA methyltransferase 3A (DNMT3A) in both untreated and PA-treated DLBCL tumors and cell lines. Assessments were made of cell viability, apoptosis, and autophagy-related protein expression following PA administration. Interaction analyses among miR-429, DNMT3A, and FOXO1 were conducted using luciferase reporter assays and methylation-specific (MSP) Polymerase chain reaction (PCR). After transfecting the miR-429 inhibitor, negative control (NC) inhibitor, shRNA against DNMT3A (sh-DNMT3A), shRNA negative control (sh-NC), overexpression vector for DNMT3A (oe-DNMT3A), or overexpression negative control (oe-NC), we evaluated the effects of miR-429 and DNMT3A on cell viability, mortality, and autophagy-related protein expression in PA-treated DLBCL cell lines. The efficacy of PA was also tested in vivo using DLBCL tumor-bearing mouse models. MiR-429 and FOXO1 expression levels were downregulated, whereas DNMT3A was upregulated in DLBCL compared to the control group. PA treatment was associated with enhanced autophagy, mediated by the upregulation of miR-429 and downregulation of DNMT3A. The luciferase reporter assay and MSP confirmed that miR-429 directly inhibits DNMT3A, thereby reducing FOXO1 methylation. Subsequent experiments demonstrated that PA promotes autophagy and inhibits DLBCL progression by upregulating miR-429 and modulating the DNMT3A/FOXO1 axis. In vivo PA significantly reduced the growth of xenografted tumors through its regulatory impact on the miR-429/DNMT3A/FOXO1 axis. Palmitic acid may modulate autophagy and inhibit DLBCL progression by targeting the miR-429/DNMT3A/FOXO1 signaling pathway, suggesting a novel therapeutic target for DLBCL management.

Indolent nonprogressive multifocal choroidal lymphoid lesions with late development of systemic lymphoma

Purpose: To report a case of indolent nonprogressive multifocal choroidal lymphoid lesions with late development of pulmonary low-grade B-cell lymphoma after lymphoid lesion regression. Methods: Case report. Results: A 79-year-old male was followed with ocular and systemic surveillance over a sixteen-year period for unilateral nonprogressive choroidal lesions presumed to be a benign lymphocytic disease of the choroid. Workups for systemic lymphoma and birdshot chorioretinopathy were negative. After sixteen years of observation, the choroidal lesions had largely regressed. Recent diagnosis of atrial fibrillation led to an incidental discovery of a right lower lobe lung lesion measuring 4.5 cm. Computerized tomography-guided biopsy showed low-grade B-cell lymphoma. There was no additional systemic disease detected. The patient underwent right lower lobectomy revealing extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue. Conclusion: Patients with indolent nonprogressive multifocal choroidal lymphoid lesions should be monitored regularly for late systemic disease, which although rare, can develop even after years of follow-up.

Eukaryotic initiation factor 3a promotes the development of diffuse large B-cell lymphoma through regulating cell proliferation

BackgroundOne-third of diffuse large B-cell lymphoma (DLBCL) patients suffer relapse after standard treatment. Eukaryotic initiation factor 3a (eIF3a) is a key player in the initial stage of translation, which has been widely reported to be correlated with tumorigenesis and therapeutic response. This study aimed to explore the biological role of eIF3a, evaluate its prognostic and therapeutic potential in DLBCL.MethodsRNA-seq datasets from GEO database were utilized to detect the expression and prognostic role of eIF3a in DLBCL patients. Protein level of eIF3a was estimated by western blot and immunohistochemical. Next, DLBCL cells were transfected with lentiviral vector either eIF3a-knockdown or empty to assess the biological role of eIF3a. Then, samples were divided into 2 clusters based on eIF3a expression and differentially expressed genes (DEGs) were identified. Function enrichment and mutation analysis of DEGs were employed to detect potential biological roles. Moreover, we also applied pan-cancer and chemosensitivity analysis for deep exploration.ResultseIF3a expression was found to be higher in DLBCL than healthy controls, which was associated with worse prognosis. The expression of eIF3a protein was significantly increased in DLBCL cell lines compared with peripheral blood mononuclear cells (PBMCs) from healthy donors. eIF3a knockdown inhibited the proliferation of DLBCL cells and the expression of proliferation-related proteins and increase cell apoptosis rate. Besides, 114 DEGs were identified which had a close linkage to cell cycle and tumor immune. eIF3a and DEGs mutations were found to be correlated to chemosensitivity and vital signal pathways. Pan-cancer analysis demonstrated that high eIF3a expression was associated with worse prognosis in several tumors. Moreover, eIF3a expression was found to be related to chemosensitivity of several anti-tumor drugs in DLBCL, including Vincristine and Wee1 inhibitor.ConclusionsWe firstly revealed the high expression and prognostic role of eIF3a in DLBCL, and eIF3a might promote the development of DLBCL through regulating cell proliferation and apoptosis. eIF3a expression was related to immune profile and chemosensitivity in DLBCL. These results suggest that eIF3a could serve as a potential prognostic biomarker and therapeutic target in DLBCL.

Secondary multicentric large B-cell lymphoma development after intestinal large T-cell lymphoma in a dog

Secondary multicentric large B-cell lymphoma development after intestinal large T-cell lymphoma in a dog

PICH deficiency limits the progression of MYC-induced B-cell lymphoma

Plk1-interacting checkpoint helicase (PICH) is a DNA translocase involved in resolving ultrafine anaphase DNA bridges and, therefore, is important to safeguard chromosome segregation and stability. PICH is overexpressed in various human cancers, particularly in lymphomas such as Burkitt lymphoma, which is caused by MYC translocations. To investigate the relevance of PICH in cancer development and progression, we have combined novel PICH-deficient mouse models with the Eμ-Myc transgenic mouse model, which recapitulates B-cell lymphoma development. We have observed that PICH deficiency delays the onset of MYC-induced lymphomas in Pich heterozygous females. Moreover, using a Pich conditional knockout mouse model, we have found that Pich deletion in adult mice improves the survival of Eμ-Myc transgenic mice. Notably, we show that Pich deletion in healthy adult mice is well tolerated, supporting PICH as a suitable target for anticancer therapies. Finally, we have corroborated these findings in two human Burkitt lymphoma cell lines and we have found that the death of cancer cells was accompanied by chromosomal instability. Based on these findings, we propose PICH as a potential therapeutic target for Burkitt lymphoma and for other cancers where PICH is overexpressed.

Hepatitis B surface antigen positivity is associated with poor short- and long-term outcomes in patients with diffuse large B-cell lymphoma who received CHOP or R-CHOP.

The development of diffuse large B-cell lymphoma (DLBCL) is closely related to the host infection status. China is a highly endemic area for hepatitis B virus (HBV) infection. It is not clear whether HBV infection has a consistent effect on the prognostic implications of patients with DLBCL in different treatment settings. We conducted a cohort study of 692 patients with DLBCL receiving three or more cycles of treatment with a CHOP or R-CHOP regimen from the First Hospital of Jilin University between July 2011 and July 2022. The patients were divided into two groups based on their hepatitis B surface antigen (HBsAg) status: HBsAg-positive (n = 84, 12.1%) and HBsAg-negative (n = 608, 87.9%) groups. Tumor specimens from 180 patients with primary DLBCL were collected for next-generation sequencing (NGS). The HBsAg-positive group had more frequent abnormal liver function (P= 0.003), hypoalbuminemia (P < 0.001), incidence of > 2 extranodal organs (P= 0.011), and spleen involvement (P < 0.001) than the HBsAg-negative group. HBsAg-positive patients had lower complete response (CR) and overall response rates (ORR) rates (all the p values < 0.05), in either the CHOP group or R-CHOP group. Among patients receiving R-CHOP, the rates of disease progression within 12 and 24 months were higher in the HBsAg-positive group than in the HBsAg-negative group (P=0.018, P=0.029). However, no significant difference in disease progression was observed between HBsAg-positive and HBsAg-negative patients in the CHOP group(P > 0.05). HBsAg positivity (OS: HR [95% CI] = 2.511 [1.214-5.192], P = 0.013) was only associated with poorer OS in the CHOP group. Whereas in the R-CHOP group, HBsAg positivity was associated with both poorer OS and PFS (OS: HR [95% CI] = 1.672 [1.050-2.665], P = 0.030; PFS: HR [95% CI] = 1.536 [1.013-2.331], P = 0.043). Additionally, HBsAg-positive patients with DLBCL also had a higher prevalence of mutations in MYC, ATM, PTPN6, and epigenetically regulated genes. These findings suggest that HBsAg-positive DLBCL patients may represent a distinct subgroup with a poorer prognosis. The standard therapies may be insufficient and new therapeutic strategies should be developed based on a better understanding of the underlying mechanisms of chemoresistance.

Development of Diffuse Large B-Cell Lymphoma and Sarcoidosis In The Course Of Multiple Myeloma: A Case Report with Literature Review

Despite significant survival increment due to treatment improvement, multiple myeloma (MM) remains an incurable disease. We herein describe a unique patient that is not only a MM long survivor despite adverse features, such as the occurrence of extramedullary disease at relapse, but also developed, sixteen years after MM diagnosis, an extranodal diffuse large B-cell lymphoma (DLBCL) of the small intestine. The patient eventually achieved cure but developed sarcoidosis two years later that regressed with corticosteroids. Today, after 26 years of follow-up the patient is in remission and in good clinical condition.

Development of Diffuse Large B-cell Lymphoma Serendipitously Led to Life-Saving Treatment in a Patient with Refractory Classical Hodgkin Lymphoma.

A 65-year-old man with generalized lymphadenopathy was diagnosed with classical Hodgkin lymphoma-Mixed cellularity via left cervical lymph node biopsy. Initial treatment with doxorubicin, bleomycin, vinblastine, and dacarbazine led to complete metabolic remission (CMR); however, recurrence developed after 6 months. Brentuximab vedotin induced partial remission followed by systemic relapse after 10 months. Nivolumab led to a second CMR, but disease progression persisted over nearly 4 years, despite treatment adjustments and local radiotherapy. Eventually, the patient was diagnosed with diffuse large B-cell lymphoma during routine esophagogastroduodenoscopy. Four courses of rituximab-CHOP therapy led to a CMR. This case highlights the importance of performing re-biopsies to detect the recurrence or progression of lymphoma.

Molecular detection of Epstein-Barr virus among Sudanese patients diagnosed with Hashimoto’s thyroiditis

ObjectivesHashimoto’s thyroiditis (HT) is the most common cause of hypothyroidism. The exact mechanism initiating the development of HT is not yet clear. This study aimed to investigate the correlation between HT and the presence of Epstein-Barr virus (EBV) in a Sudanese population.ResultsEBV-LMP1 was detected in 11.1% of HT cases, which is consistent with previous studies. Studies have reported a wide range of frequencies indicating the presence of EBV in HT, and patients with autoimmune thyroiditis have increased titers of anti-EBV antibodies in their sera compared to healthy subjects. Intrathyroidal EBV-infected B cells may be responsible for the increased risk of development of B-cell lymphoma in the thyroid gland in patients with autoimmune thyroiditis. Our study suggests that regular follow-up is necessary for patients diagnosed with HT and are positive for EBV, as antiviral therapy is not applicable due to the risk of thyroid dysfunction. The study suggests an association between EBV and HT, but causation cannot be determined. The study also highlights the need for further research to determine the viral role and correlate it with the severity and progression of HT.

Oncolytic virus oHSV2 combined with PD-1/PD-L1 inhibitors exert antitumor activity by mediating CD4 + T and CD8 + T cell infiltration in the lymphoma tumor microenvironment

A novel therapeutic regimen showed that the oncolytic type II herpes simplex virus (oHSV2) was able to prevent colorectal cancer growth, recurrence, and metastasis. However, no study has yet explored whether oHSV2 has an impact on the development of diffuse large B-cell lymphoma (DLBCL). We chose the clinical chemotherapeutic drug doxorubicin (DOX) as a positive control to evaluate the effect of oHSV2 infection on the apoptotic, invasive, and proliferative capacity of DLBCL cells. We next further explored the therapeutic efficacy of oncolytic virus oHSV2 or DOX in DLBCL tumor bearing BALB/c mice, and evaluated the infiltration of CD8 + T cells and CD4 + T cells in tumor tissues. A pathological approach was used to explore the effects of oHSV2 on various organs of tumor bearing mice, including the heart, liver, and kidney. Next, SU-DHL-4 cells were co-cultured with cytotoxic T lymphocytes (CTLs) to mimic the tumor immune microenvironment (TME), to explore the impact of oHSV2 on the immune environment at the cellular level, and then analyzed the relationship between oHSV2 and the PD-1/PD-L1 immune-checkpoint. Subsequently, we further validated the efficacy of combined oHSV2 and PD-L1 treatment on transplanted tumor growth in mice at the in vivo level. DLBCL cells were sensitive to the action of the oncolytic virus oHSV2, and the decline in their proliferative activity showed a time-and dose-dependent manner. oHSV2 and DOX intervention preeminently increased the cell apoptosis, restrained cell proliferation and invasion, with the greatest changes occurring in response to oHSV2 infection. oHSV2 application effectively improved the immune status of the tumor microenvironment, favoring the invasion of CD8 + T and CD4 + T cells, thereby enhancing their antitumor effects. Besides, oHSV2 treatment has a safety profile in the organs of tumor bearing mice and indeed inhibits the PD-1/PD-L1 immune checkpoint in DLBCL. Interestingly, the combination of oHSV2 and PD-L1 antibodies results in more profound killing of DLBCL cells than oHSV2 infection alone, with a significant increase in the proportion of CD4 + T cells and CD8 + T cells. The antitumor effect was the best after combining oHSV2 and PD-L1 antibodies, suggesting that the combination therapy of oHSV2 and PD-L1 would have a better prospect for clinical application.

TRAF2/3 deficient B cells resist DNA damage-induced apoptosis via NF-κB2/XIAP/cIAP2 axis and IAP antagonist sensitizes mutant lymphomas to chemotherapeutic drugs

Deletion of TRAF2 or TRAF3 in B cells prolongs their survival. However, it remains unknown whether deletion of such factors affects B cells’ ability to tolerate DNA damage, which can be induced by chemotherapeutics and cause apoptosis. Genetic alterations of TRAF2 or TRAF3 are observed in subsets of human B-cell lymphomas and B cell-specific deletion of TRAF3 led to lymphoma development in aged mice. However, it remains unknown whether double deficiency of TRAF2 and TRAF3 accelerates B-cell lymphomagenesis. Here, we showed that B cell-specific TRAF2/3 double deficient (B-TRAF2/3-DKO) B cells were remarkably more resistant to DNA damage-induced apoptosis via upregulating cIAP2 and XIAP, which in turn attenuates caspase-3 activation. Mechanistically, resistance to DNA damage-induced apoptosis required NF-κB2, which effects by upregulating XIAP and cIAP2 transcription. B-TRAF2/3-DKO mice exhibited a shorter lifespan and succumbed to splenomegaly and lymphadenopathy. Unexpectedly, the incidence of B-cell lymphoma development in B-TRAF2/3-DKO mice was relatively rare (∼10%). Sequencing B cell receptor repertoire of diseased B cells revealed that TRAF2/3 deficiency caused abnormal oligoclonal or clonal expansion of B cells. While a fraction of mutant B cells (25–43%) from aged diseased mice harbored recurrent chromosomal translocations, primary B cells isolated from young B-TRAF2/3-DKO mice had no detectable chromosomal alterations, suggesting that TRAF2/3 deficiency per se does not cause evident genomic instability in B cells. Chemo-resistant TRAF3-deficient B-cell lymphomas were sensitized to chemotherapeutic drugs by blocking IAP activity using IAP antagonist. We conclude that double deficiency of TRAF2 and TRAF3 does not accelerate B-cell lymphomagenesis. Our studies provide insight into mechanisms regulating DNA damage-induced apoptosis and may help develop effective therapies targeting mutant B-cell lymphomas using IAP antagonist.

Investigation of Molecular Mechanisms Involved in Hepatitis B Virus Associated B-cell NonHodgkin Lymphoma (B-NHL)

The Non-Hodgkin Lymphoma (NHL) is a heterogeneous group of malignancies ranked as the most common haematological cancer worldwide, more than 544 000 new cases being reported in 2020. More recent epidemiological studies have shown an increased risk of several types of B-cell Lymphoma development, the most prevalent being diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) subtypes, in patients infected with hepatitis B virus (HBV). These patients are more difficult to treat and their survival rate is lower compared to uninfected people. HBV is known as a hepatotropic virus, although viral HBV-DNA has been identified in extrahepatic tissues, such as kidney, pancreas or peripheral blood mononuclear cells (PBMC). However, the mechanistic relationship between HBV infection and lymphoid cancer is not known. Preliminary data have shown that NTCP, the specific HBV receptor is expressed in normal B cells. After exposure to HBV viral particles, B cells become capable of producing viral core antigens (HBcAg). Antiviral roles and/or cancer-promotion functions in B-cells of APOBEC3 deaminases overexpression remain to be determined.

Cytokine profiles in patients with newly diagnosed diffuse large B-cell lymphoma: IL-6 and IL-10 levels are associated with adverse clinical features and poor outcomes

BackgroundThe development of diffuse large B-cell lymphoma (DLBCL), a prevalent subgroup of non-Hodgkin lymphoma (NHL), potentially involves various cytokines. We aimed to determine the correlation between deregulated serum levels of cytokines and clinical features and investigate their impact on the prognosis of patients with DLBCL. MethodsWe conducted a retrospective study of 77 patients with newly diagnosed DLBCL to explore the relationships between different cytokines, adverse clinical features, and poor outcomes. The Mann–Whitney U test was used to compare the cytokine profiles between patients with DLBCL and healthy controls. The Kaplan–Meier method was used to analyze the probability of survival, and the log-rank tests were used to evaluate the differences between survival curves. The Cox proportional hazards regression model was used to performed univariate and multivariate analyses to evaluate prognostic variables for survival analyze. ResultsSerum levels of interleukin-2 (IL-2), tumor necrosis factor (TNF)-α, IL-6, IL-10, and IFN-γ were significantly elevated in patients with untreated DLBCL. Serum levels of IL-6 and IL-10 were significantly higher in patients with an International Prognostic Index (IPI) of 3–5, bone marrow involvement, serum levels of LDH ≥ 250 U/L, and β2-microglobulin (β2-MG) levels ≥ 2.3 mg/L. Patients with B symptoms only had higher serum IL-10 levels, whereas patients with a partial response or no response to treatment had significantly elevated serum levels of IL-6 as well as IL-10. Significant positive correlations were observed between the levels of IL-6 and IL-10 with those of β2-MG and LDH. Patients with levels of IL-6 ≥ 4.5 or IL-10 ≥ 5.0 pg/mL, as well as combined elevated IL-6 and IL-10 levels, exhibited shorter progression-free survival and overall survival. Additionally, univariate and multivariate analyses revealed that serum levels of IL-6 ≥ 4.5 pg/mL and IL-10 ≥ 5.0 pg/mL and IPI 3–5 were independent prognostic factors for relapse and survival in patients with DLBCL. ConclusionsPre-treatment serum IL-6 and IL-10 levels in patients with newly diagnosed DLBCL might be powerful markers for determining treatment response and predicting the prognosis of DLBCL.

Expression, purification, and microscopic characterization of the tumor suppressor KLHL6

Kelch-like protein 6 (KLHL6) plays a critical role in preventing the development and survival of diffuse large B-cell lymphoma (DLBCL) through its involvement in the ubiquitin proteasome system. Specifically, KLHL6 binds to cullin3 (Cul3) and the substrate, facilitating the assembly of the E3 ligase responsible for substrate ubiquitination. It is imperative to investigate the precise function of KLHL6 by conducting a structural analysis of its interaction with Cul3. Here, we present the expression, purification, and characterization of the full-length KLHL6. Our findings demonstrate that the addition of a Sumo-tag significantly enhances the production of KLHL6, while also improving its stability and solubility. Moreover, through gel filtration and negative staining electron microscopy (EM), we observed that KLHL6 adopts a homomultimeric form in solution. Additionally, we found that the presence of Cul3NTD enhances the stability and homogeneity of KLHL6 by forming a complex. Consequently, the successful expression and purification of full-length KLHL6 serve as a foundation for further investigations into the structure and function of the KLHL6/Cullin3/Rbx1 substrate complex, as well as provide a potential strategy for studying other proteins within the KLHL family that possess similar characteristics.

Approach to relapsed CLL including Richter Transformation

Approach to relapsed CLL including Richter Transformation

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

Introduction: N-acetyltransferase 10 (NAT10) is the only confirmed regulator to mediate the N4-acetylcytidine (ac4C) modification of mRNA and is crucial for mRNA stability and translation efficiency. However, its role in diffuse large B-cell lymphoma (DLBCL) development and prognosis has not yet been explored. Herein, we explored the functional significance and regulatory mechanism of NAT10 mediated mRNA ac4C modification in DLBCL, which is expected to propose novel therapeutic strategy. Methods: The expression levels of NAT10 were evaluated in DLBCL cell lines and lymph node biopsies tissues, and its prognostic value in patients was further analyzed. Stable NAT10 knockout DLBCL cell lines were constructed using CRISPR/Cas9 mediated genomic deletion. The biological functions of NAT10 in DLBCL cells were analyzed in vitro by cell proliferation and cell cycle assays. Xenograft models were used to analyze the effect of NAT10 on the tumorigenesis of DLBCL cells in vivo. RNA sequencing, acetylated RNA immunoprecipitation sequencing (acRIP-seq), LC-MS/MS, RIP and RNA stability analyses were performed to explore the mechanism by which NAT10 functions in DLBCL progression. Results: NAT10 was upregulated in DLBCL cell lines and tissues. NAT10 high expression was associated with poor patient prognosis. Knockout of NAT10 impaired cellular phase progression and proliferation of DLBCL. Further analysis revealed that NAT10-mediated ac4C acetylation of SLC30A9 transcript and subsequently stabilized SLC30A9 mRNA, leading to activation of AMPK signaling and thereby facilitating DLBCL progression (Figure 1). Keywords: aggressive B-cell non-Hodgkin lymphoma, diagnostic and prognostic biomarkers, genomics, epigenomics, and other -omics No conflicts of interests pertinent to the abstract.