Development Of Lymphoma Research Articles

Immune dysregulation as a leading principle for lymphoma development in diverse immunological backgrounds

Lymphoma is a heterogeneous group of malignancies arising from lymphocytes, which poses a significant challenge in terms of diagnosis and treatment due to its diverse subtypes and underlying mechanisms. This review aims to explore the shared and distinct features of various forms of lymphoma predisposing conditions, with a focus on genetic, immunological and molecular aspects. While diseases such as autoimmune disorders, inborn errors of immunity and iatrogenic immunodeficiencies are biologically and immunologically distinct, each of these diseases results in profound immune dysregulation and a predisposition to lymphoma development. Interestingly, the increased risk is often skewed towards a particular subtype of lymphoma. Patients with inborn errors of immunity in particular present with extreme forms of lymphoma predisposition, providing a unique opportunity to study the underlying mechanisms. External factors such as chronic infections and environmental exposures further modulate the risk of lymphoma development. Common features of conditions predisposing to lymphoma include: persistent inflammation, recurrent DNA damage or malfunctioning DNA repair, impaired tumor surveillance and viral clearance, and dysregulation of fundamental cellular processes such as activation, proliferation and apoptosis. Our growing understanding of the underlying mechanisms of lymphomagenesis provides opportunities for early detection, prevention and tailored treatment of lymphoma development.

Assessment of Bcl-xL, TAX, and HBZ Gene Expression in Adult T cell Leukemia/Lymphoma Patients.

Adult T cell leukemia/lymphoma is a malignancy with a poor prognosis caused by human T lymphocyte virus type 1 (HTLV-1) infection. Tax and HBZ are two major viral proteins that may be involved in oncogenesis by disrupting apoptosis. Because Bcl-xL plays an integral role in the anti-apoptotic pathway, this study examines the interaction between host apoptosis and oncoproteins. We investigated 37 HTLV-1-infected individuals, including 18 asymptomatic and 19 adult T cell leukemia/lymphoma (ATLL) subjects. mRNA was extracted and converted to cDNA from peripheral blood mononuclear cells, and then gene expression was determined using TaqMan q-PCR. Moreover, the HTLV-1 proviral load (PVL) was also measured using a commercial absolute quantification kit (Novin Gene, Iran). Data analysis revealed that the mean of TAX, HBZ, and PVL was significantly higher among the study groups (ATLL and carrier groups p = .003, p = .000, and p = .002 respectively). There was no statistical difference in Bcl-xL gene expression between the study groups (p = .323). It is proposed that this anti-apoptotic pathway may not be directly involved in the development of ATLL lymphoma. Bcl-xL, TAX, HBZ gene expression, and PVL can be utilized as prognostic markers.

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.

Leukemic presentation and progressive genomic alterations of MCD/C5 diffuse large B-cell lymphoma (DLBCL).

Diffuse large B-cell lymphoma (DLBCL) is a heterogenous group of lymphoid malignancies. Based on gene expression profiling, it has been subdivided into germinal center (GC)-derived and activated B-cell (ABC) types. Advances in molecular methodologies have further refined the subclassification of DLBCL, based on recurrent genetic abnormalities. Here, we describe a distinct case of DLBCL that presented in leukemic form. DNA sequencing targeting 275 genes revealed pathogenically relevant mutations of CD79B, MyD88, TP53, TBL1XR1, and PIM1 genes, indicating that this lymphoma would be best classified as MCD/C5 DLBCL, an ABC subtype. Despite an initial good clinical response to BTK inhibitor ibrutinib, anti-CD20 antibody rituxan, alkylating agent bendamustine, and hematopoietic stem-cell transplant, the lymphoma relapsed, accompanied by morphologic and molecular evidence of disease progression. Specifically, the recurrent tumor developed loss of TP53 heterozygosity (LOH) and additional chromosomal changes central to ABC DLBCL pathogenesis, such as PRDM1 loss. Acquired resistance to ibrutinib and rituxan was indicated by the emergence of BTK and FOXO1 mutations, respectively, as well as apparent activation of alternative cell-activation pathways, through copy-number alterations (CNAs), detected by high-resolution chromosomal microarrays. In vitro, studies of relapsed lymphoma cells confirmed resistance to standard BTK inhibitors but sensitivity to vecabrutinib, a noncovalent inhibitor active against both wild-type as well as mutated BTK. In summary, we provide in-depth molecular characterization of a de novo leukemic DLBCL and discuss mechanisms that may have contributed to the lymphoma establishment, progression, and development of drug resistance.

PD-L1 Is Involved in the Development of Non-Hodgkin's Lymphoma by Mediating Circulating Lymphocyte Apoptosis.

Lymphocyte apoptosis plays a crucial role in tumor-induced immunosuppression. Programmed death ligand-1 (PD-L1) blocks lymphocyte activation via its receptor, PD-1. However, PD-L1/PD-1 expression and its role in enhancing immune suppression in non-Hodgkin lymphoma (NHL) have not been identified. The purpose of the study was to assess PD-L1/PD-1 expression in circulating lymphocytes in NHL and its role in immunosuppression. Twenty newly diagnosed NHL patients and twenty normal volunteers were enrolled in the study. PD-L1/PD-1 expression in circulating lymphocytes and the apoptosis of lymphocyte subsets were assessed using flow cytometry. The findings revealed that the PD-L1 expression in circulating CD3+, CD3+CD4+, CD3+CD8+, and CD20+ lymphocytes were dramatically upregulated in NHL patients (p < 0.001), whereas peripheral lymphocytes expressed low levels of PD-1. Compared with normal volunteers, a significant increase in lymphocyte apoptosis was revealed by annexin-V binding on T and B lymphocytes (p < 0.001). Peripheral lymphocytes expressing PD-L1 were four times more vulnerable to apoptosis than those expressing PD-1. Our findings imply that PD-L1 upregulation contributes to NHL development by promoting circulating lymphocyte apoptosis. This research adds to our understanding of the function of the PD-L1/PD-1 pathway in tumor evasion, establishing a novel therapeutic target in NHL. The results offer additional evidence for the immunomodulatory role of PD-L1 in circulating lymphocytes, providing a rationale for further investigations into immunological dysfunctions resulting from NHL. PD-L1+ lymphocytes could be employed as a biomarker to assess the effectiveness of immune systems and predict illness in patients with NHL.

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.

Role of cytokine in malignant T-cell metabolism and subsequent alternation in T-cell tumor microenvironment.

T cells are an important component of adaptive immunity and T-cell-derived lymphomas are very complex due to many functional sub-types and functional elasticity of T-cells. As with other tumors, tissues specific factors are crucial in the development of T-cell lymphomas. In addition to neoplastic cells, T- cell lymphomas consist of a tumor micro-environment composed of normal cells and stroma. Numerous studies established the qualitative and quantitative differences between the tumor microenvironment and normal cell surroundings. Interaction between the various component of the tumor microenvironment is crucial since tumor cells can change the microenvironment and vice versa. In normal T-cell development, T-cells must respond to various stimulants deferentially and during these courses of adaptation. T-cells undergo various metabolic alterations. From the stage of quiescence to attention of fully active form T-cells undergoes various stage in terms of metabolic activity. Predominantly quiescent T-cells have ATP-generating metabolism while during the proliferative stage, their metabolism tilted towards the growth-promoting pathways. In addition to this, a functionally different subset of T-cells requires to activate the different metabolic pathways, and consequently, this regulation of the metabolic pathway control activation and function of T-cells. So, it is obvious that dynamic, and well-regulated metabolic pathways are important for the normal functioning of T-cells and their interaction with the microenvironment. There are various cell signaling mechanisms of metabolism are involved in this regulation and more and more studies have suggested the involvement of additional signaling in the development of the overall metabolic phenotype of T cells. These important signaling mediators include cytokines and hormones. The impact and role of these mediators especially the cytokines on the interplay between T-cell metabolism and the interaction of T-cells with their micro-environments in the context of T-cells lymphomas are discussed in this review article.

Hemin treatment drives viral reactivation and plasma cell differentiation of EBV latently infected B cells.

Epstein-Barr virus (EBV) and Plasmodium falciparum have a well described role in the development of endemic Burkitt lymphoma (BL), yet the mechanisms involved remain unknown. A major hallmark of malarial disease is hemolysis and bystander eryptosis of red blood cells, which causes release of free heme in large quantities into peripheral blood. We hypothesized that heme released during malaria infection drives differentiation of latently infected EBV-positive B cells, resulting in viral reactivation and release of infectious virus. To test this hypothesis, we used the EBV-positive Mutu I B-cell line and treated with hemin (the oxidized form of heme) and evaluated evidence of EBV reactivation. Hemin treatment resulted in the expression of EBV immediate early, early and late lytic gene transcripts. In addition, expression of CD138, a marker of plasma cells was co-expressed with the late lytic protein gp350 on hemin treated Mutu I cells. Finally, DNase-resistant EBV DNA indicative of virion production was detected in supernatant. To assess the transcriptional changes induced by hemin treatment, RNA sequencing was performed on mock- and hemin-treated Mutu I cells, and a shift from mature B cell transcripts to plasma cell transcripts was identified. To identify the mechanism of hemin-induced B cell differentiation, we measured levels of the plasma cell transcriptional repressor, BACH2, that contains specific heme binding sites. Hemin treatment caused significant degradation of BACH2 by 24 hours post-treatment in four BL cell lines (two EBV positive, two EBV negative). Knockdown of BACH2 in Mutu I cells using siRNAs significantly increased CD138+gp350+ cells to levels similar to treatment with hemin. This suggested that hemin induced BACH2 degradation was responsible for plasma cell differentiation and viral reactivation. Together, these data support a model where EBV reactivation can occur during malaria infection via heme modulation, providing a mechanistic link between malaria and EBV.

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.

BCL-W makes only minor contributions to MYC-driven lymphoma development.

The BH3-mimetic drug Venetoclax, a specific inhibitor of anti-apoptotic BCL-2, has had clinical success for the treatment of chronic lymphocytic leukaemia and acute myeloid leukaemia. Attention has now shifted towards related pro-survival BCL-2 family members, hypothesising that new BH3-mimetic drugs targeting these proteins may emulate the success of Venetoclax. BH3-mimetics targeting pro-survival MCL-1 or BCL-XL have entered clinical trials, but managing on-target toxicities is challenging. While increasing evidence suggests BFL-1/A1 is a resistance factor for diverse chemotherapeutic agents and BH3-mimetic drugs in haematological malignancies, few studies have explored the role of BCL-W in the development, expansion, and therapeutic responses of cancer. Previously, we found that BCL-W was not required for the ongoing survival and growth of various established human Burkitt lymphoma and diffuse large B cell lymphoma cell lines. However, questions remained about whether BCL-W impacts lymphoma development. Here, we show that BCL-W appears dispensable for MYC-driven lymphomagenesis, and such tumours arising in the absence of BCL-W show no compensatory changes to BCL-2 family member expression, nor altered sensitivity to BH3-mimetic drugs. These results demonstrate that BCL-W does not play a major role in the development of MYC-driven lymphoma or the responses of these tumours to anti-cancer agents.

Characterizing the role of Phlda3 in the development of acute toxicity and malignant transformation of hematopoietic cells induced by total-body irradiation in mice

The tumor suppressor p53 is a transcriptional factor that plays a crucial role in controlling acute toxicity and long-term malignant transformation of hematopoietic cells induced by genotoxic stress such as ionizing radiation. Among all transcriptional targets of p53, one gene that is robustly induced by radiation is the pleckstrin homology domain-only protein Phlda3. However, the role that Phlda3 plays in regulating the response of hematopoietic cells to radiation is unknown. Here, using isogenic cell lines and genetically engineered mouse models, we showed that radiation induces Phlda3 in human leukemia cells and mouse normal hematopoietic cells in a p53-dependent manner. However, deletion of the Phlda3 gene did not ameliorate radiation-induced acute hematologic toxicity. In addition, distinct from mice that lose p53, loss of Phlda3 did not alter the latency and incidence of radiation-induced thymic lymphoma in mice. Remarkably, whole-exome sequencing data showed that lymphomas in irradiated Phlda3+/+ mice harbor a significantly higher number of single nucleotide variants (SNVs) and indels compared to lymphomas in irradiated Phlda3+/− and Phlda3−/− littermates. Together, our results indicate that although deletion of Phlda3 does not accelerate the development of radiation-induced thymic lymphoma, fewer SNVs and indels are necessary to initiate lymphomagenesis after radiation exposure when Phlda3 is silenced.

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.

Richter Transformation of Chronic Lymphocytic Leukemia-Are We Making Progress?

The treatment paradigm of chronic lymphocytic leukemia (CLL) has dramatically changed with the advent of novel targeted agents over the past decade. Richter transformation (RT), or the development of an aggressive lymphoma from a background of CLL, is a well-recognized complication of CLL and carries significantly poor clinical outcomes. Here, we provide an update on current diagnostics, prognostication, and contemporary treatment of RT. Several genetic, biologic, and laboratory markers have been proposed as candidate risk factors for the development of RT. Although a diagnosis of RT is typically suspected based on clinical and laboratory findings, tissue biopsy is essential for histopathologic confirmation of diagnosis. The standard of care for RT treatment at this time remains chemoimmunotherapy with the goal of proceeding to allogeneic stem cell transplantation in eligible patients. Several newer treatment modalities are being studied for use in the management of RT, including small molecules, immunotherapy, bispecific antibodies, and chimeric antigen receptor T-cell (CAR-T) therapy. The management of patients with RT remains a challenge. Ongoing trials show enormous promise for newer classes of therapy in RT, with the hope being that these agents can synergize, and perhaps supersede, the current standard of care in the near future.

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.

Multiomics and Multidimensional Testing for Efficacy Monitoring of Patients with Lymphoma

To explore the role of a new blood-based, multiomics and multidimensional method for evaluating the efficacy of patients with lymphoma. 10 ml peripheral blood was extracted from each patient, and the genomic copy number aberrations (CNA) and fragment size (FS) were evaluated by low-depth whole genome sequencing of cfDNA, and the level of a group of plasma tumor marker (PTM) were detected at the same time. The cancer efficacy score (CES) was obtained by standardized transformation of the value of above three numerical indexes, and the changes of CES before and after treatment were compared to evaluate the patient's response to the treatment regimen. A total of 35 patients' baseline data were collected, of which 23 cases (65.7%) had elevated CES values. 18 patients underwent the first time test. The results showed that the CES value of 9 patients with positive baseline CES decreased significantly at the first test, and the efficacy evaluation was PR, which was highly consistent with the imaging evaluation results of the same period. At the same time, the CNA variation spectrum of all patients were evaluated and it was found that 23 patients had partial amplification or deletion of chromosome fragments. The most common amplification site was 8q24.21, which contains important oncogenes such as MYC. The most common deletion sites were 1p36.32, 4q21.23, 6q21, 6q27, 14q32.33, and tumor suppressor-related genes such as PRDM1, ATG5, AIM1, FOXO3 and HACE1 were expressed in the above regions, so these deletions may be related to the occurrence and development of lymphoma. With the advantages of more convenience, sensitivity and non-invasive, this multiomics and multidimensional efficacy detection method can evaluate the tumor load of patients with lymphoma at the molecular level, and make more accurate efficacy evaluation, which is expected to serve the clinic better.

Approach to relapsed CLL including Richter Transformation

Approach to relapsed CLL including Richter Transformation

Diagnostic role of CXCL13 biomarker in primary Sjogren's syndrome patients with parotid non-Hodgkin's lymphoma complication

IntroductionSerum biomarkers are important predictive factors for development of parotid non-Hodgkin's lymphoma (NHL) complication in primary Sjogren's syndrome (pSS) patients. The aim was to evaluate the diagnostic accuracy of serum CXCL13 chemokine in pSS patients with parotid NHL complication. Material and methodsSerum CXCL13 chemokine was assessed in 33 patients with pSS [7 with parotid NHL complication (pSS+NHL subgroup) and 26 without NHL (pSS-NHL subgroup)] and 30 healthy subjects. ResultsThe serum CXCL13 levels in pSS+NHL subgroup [175.2 (107.9–220.4) pg/ml] were significantly higher comparing to the healthy subjects group (p=0.018) and the pSS-NHL subgroup (p=0.048). A cut-off value of 123.45pg/ml (Se=71.4%, Sp=80.8%, AUROC=0.747) was established for parotid lymphoma diagnosis. ConclusionThe serum CXCL13 biomarker could be considered a valuable tool for the diagnosis of parotid NHL complication in pSS patients.

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.

Umbelliferone loaded PEGylated liposomes: preparation, characterization and its mitigatory effects on Dalton's ascites lymphoma development.

Umbelliferone (UB) is a phenylpropanoid-based pharmacologically active agent with promising anti-tumor activities. However, complete elucidation of its therapeutic efficacy remains challenging due to low solubility and bioavailability. The present study aimed to develop a liposomal delivery system for UB to enhance its therapeutic efficacy against Dalton's ascites lymphoma tumor model. Umbelliferone-encapsulated nanoliposomes (nLUB) were prepared using the thin-film hydration method and performed a series of characterizations to confirm successful development. The nLUB showed a particle size of 116 ± 3.2nm with a negative surface charge and encapsulation efficiency of 78%. In vitro study results showed that nLUB treatment significantly enhanced cellular uptake and apoptosis induction in lymphoma cells compared to free UB. nLUB treatment significantly stabilized body weight, reduced tumor growth, and improved the serum biochemical and hematological parameters of experimental animals, thereby improving their overall survivability compared to an free UB. Our result indicates that nanoencapsulation enhanced the therapeutic potential of UB, which may find its way to clinical application in the near future.

AMD3100-Mediated CXCR4 Inhibition Impairs Development of Primary Lymphoma of the Central Nervous System

A hallmark of primary lymphoma of the central nervous system (CNS; PCNSL) is the strong CXCR4 expression of the tumor cells, the function of which is still unknown. Invitro treatment of BAL17CNS lymphoma cells by AMD3100, which inhibits CXCR4-CXCL12 interactions, resulted in the significantly differential expression of 273 genes encoding proteins involved in cell motility, cell-cell signaling and interaction, hematological system development and function, and immunologic disease. Among the genes down-regulated was the one encoding CD200, a regulator of CNS immunologic activity. These data directly translated into the invivo situation; BAL17CNS CD200 expression was down-regulated by 89% (3% versus 28% CD200+ lymphoma cells) in AMD3100-treated versus untreated mice with BAL17CNS-induced PCNSL. Reduced lymphoma cell CD200 expression may contribute to the markedly increased microglial activation in AMD3100-treated mice. AMD3100 also maintained the structural integrity of blood-brain barrier tight junctions and the outer basal lamina of cerebral blood vessels. Subsequently, lymphoma cell invasion of the brain parenchyma was impaired, and maximal parenchymal tumor size was significantly reduced by 82% in the induction phase. Thus, AMD3100 qualified as a potentially attractive candidate to be included into the therapeutic concept of PCNSL. Beyond therapy, CXCR4-induced suppression of microglial activity is of general neuroimmunologic interest and identifies CD200 expressed by the lymphoma cells as a novel mechanism of immune escape in PCNSL.