The evaluation of risk factors for prolonged viral shedding during anti-SARS-CoV-2 monoclonal antibodies and long-term administration of antivirals in COVID-19 patients with B-cell lymphoma treated by anti-CD20 antibody.

BACKGROUND: The global impact of the coronavirus disease 2019 (COVID-19) pandemic has resulted in significant morbidity and mortality. Immunocompromised patients, particularly those treated for B-cell lymphoma, have shown an increased risk of persistent infection with SARS-CoV-2 and severe outcomes and mortality. Multi-mutational SARS-CoV-2 variants can arise during the course of such persistent cases of COVID-19. No optimal, decisive strategy is currently available for patients with persistent infection that allows clinicians to sustain viral clearance, determine optimal timing to stop treatment, and prevent virus reactivation. We introduced a novel treatment combining antivirals, neutralizing antibodies, and genomic analysis with frequent monitoring of spike-specific antibody and viral load for immunocompromised patients with persistent COVID-19 infection. The aim of this retrospective study was to report and evaluate the efficacy of our novel treatment for immunocompromised B-cell lymphoma patients with persistent COVID-19 infection. METHODS: This retrospective descriptive analysis had no controls. Patients with B-cell lymphoma previously receiving immunotherapy including anti-CD20 antibodies, diagnosed as having COVID-19 infection, and treated in our hospital after January 2022 were included. We selected anti-SARS-CoV-2 monoclonal antibodies according to subvariants. Every 5 days, viral load was tested by RT-PCR, with antivirals continued until viral shedding was confirmed. Primary outcome was virus elimination. Independent predictors of prolonged viral shedding time were determined by multivariate Cox regression. RESULTS: Forty-four patients were included in this study. Thirty-five patients received rituximab, 19 obinutuzumab, and 26 bendamustine. Median treatment duration was 10 (IQR, 10-20) days; 22 patients received combination antiviral therapy. COVID-19 was severe in 16 patients, and critical in 2. All patients survived, with viral shedding confirmed at median 28 (IQR, 19-38) days. Bendamustine use or within 1 year of last treatment for B-cell lymphoma, and multiple treatment lines for B-cell lymphoma significantly prolonged time to viral shedding. CONCLUSIONS: Among 44 consecutive patients treated, anti-SARS-CoV-2 monoclonal antibodies and long-term administration of antiviral drugs, switching, and combination therapy resulted in virus elimination and 100% survival. Bendamustine use, within 1 year of last treatment for B-cell lymphoma, and multiple treatment lines for B-cell lymphoma were the significant independent predictors of prolonged viral shedding time.

Unraveling the role of hepatitis B virus DNA integration in B-cell lymphomagenesis.

BACKGROUND: Studies have shown that hepatitis B virus (HBV)-associated B-cell non-Hodgkin lymphoma (NHL) constitutes a unique subgroup with distinct clinical features. It still leaves open the question of whether the integration of HBV DNA into the B-cell genome is a causal mechanism in the development of lymphoma. METHODS: Using the hybridisation capture-based next generation sequencing and RNA sequencing, we characterised the HBV integration pattern in 45 HBV-associated B-cell NHL tumour tissues. RESULTS: A total of 354 HBV integration sites were identified in 13 (28.9%) samples, indicating the relatively low integration frequency in B-cell NHLs. High plasma HBV DNA loads were not associated with the existence of HBV integration. The insertion sites distributed randomly across all the lymphoma genome without any preferential hotspot neither at the chromosomal level nor at the genetic level. Intriguingly, most HBV integrations were nonclonal in B-cell NHLs, implying that they did not confer a survival advantage. Analysis of the paired diagnosis-relapse samples showed the unstable status of HBV integrations during disease progression. Furthermore, transcriptomic analysis revealed the limited biological impact of HBV integration. CONCLUSION: Our study provides an unbiased HBV integration map in B-cell NHLs, revealing the insignificant role of HBV DNA integration in B-cell lymphomagenesis.

A new compound, phomaherbarine A, induces cytolytic reactivation in epstein-barr virus-positive B cell lines.

Epstein-Barr virus (EBV), the first virus found to induce cancer in humans, has been frequently detected in various types of B cell lymphomas. During its latent phase, EBV expresses a limited set of proteins crucial for its persistence. Induction of the lytic phase of EBV has shown promise in the treatment of EBV-associated malignancies. The present study assessed the ability of phomaherbarine A, a novel compound derived from the endophytic fungus Phoma herbarum DBE-M1, to stimulate lytic replication of EBV in B95-8 cells. Phomaherbarine A was found to efficiently initiate the expression of both early and late EBV lytic genes in B95-8 cells, with this initiation being further heightened by the addition of phorbol myristate acetate and sodium butyrate. Moreover, phomaherbarine A demonstrated notable cytotoxicity against the EBV-associated B cell lymphoma cell lines B95-8 and Raji. Mechanistically, phomaherbarine A induces apoptosis in these cells through the activation of caspase-3/7. When combined with ganciclovir, phomaherbarine A does not interfere with the reduction of viral replication by ganciclovir and sustains its apoptosis induction. In conclusion, these findings indicate that phomaherbarine A may be a promising candidate for therapeutic intervention in patients with EBV-associated B cell lymphomas.

Analysis of hepatitis B virus infection in 1424 patients with different pathological types of lymphoma (2018-2022): A real-world, retrospective study.

OBJECTIVE: Recent studies have found a high prevalence of hepatitis B virus (HBV) infection in patients with non-Hodgkin's lymphoma (NHL), especially B-cell non-Hodgkin's lymphoma (B-NHL). However, most studies did not classify it and analyze the correlation between HBV and its various subtypes. METHODS: The authors retrospectively analyzed 1424 patients with lymphoma. Differences in the prevalence of HBV infection in patients with different pathological types of lymphoma were analyzed. The clinical characteristics, progression-free survival (PFS), and overall survival (OS) of HBV-positive and negative B-NHL subtypes were compared according to HBV infection. RESULTS: The HBV infection rate in NHL patients was 7.65%, which was higher than that in HL patients (2.59%, p < 0.05). The HBV infection rate in the B-NHL was higher than that in the T-cell non-Hodgkin's lymphoma (T-NHL) (8.14% vs. 4.95%). The HBV infection rate in the aggressive B-NHL was similar to that of the indolent B-NHL (8.30% vs. 7.88%), and the highest HBV infection rates were found in diffuse large B-cell lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma, but no significant differences in clinical characteristics, PFS, and OS were seen between HBV-positive and negative patients in the two subtypes. CONCLUSIONS: There was an association between HBV infection and the development of NHL and HBV infection may play a role in the pathogenesis of B-NHL, but not T-NHL.

EBV-associated lymphoproliferative disease post-CAR-T cell therapy.

Epstein-Barr virus (EBV)-associated lymphoproliferative diseases (EBV-LPDs) are common complications that occur after solid organ transplantation or allogeneic hematopoietic stem-cell transplantation (HSCT). However, their occurrence and treatment post-chimeric antigen receptor-modified T (CAR-T) cell therapy has not been reported. Two patients had been diagnosed with EBV-positive aggressive B-cell lymphoma and experienced relapses after multiple lines of treatment. After receiving CAR-T cell therapy in tandem with autologous HSCT, the patients achieved complete remission. However, with a median time of 38.5 months after CAR-T cell therapy, B-cell-derived EBV-LPDs were diagnosed, and they were relieved through the administration of immune checkpoint inhibitor or B-cell-depleting agents. Collectively, our report suggests that EBV-LPDs may represent a long-term adverse event after CAR-T cell therapy, especially in patients who previously had EBV-positive disorders, and they can be resolved by immune normalization strategy or B-cell depleting therapy.

A STING inhibitor suppresses EBV-induced B cell transformation and lymphomagenesis.

Epstein-Barr virus-associated lymphoproliferative disease (EBV-LPD) is frequently fatal. Innate immunity plays a key role in protecting against pathogens and cancers. The stimulator of interferon genes (STING) is regarded as a key adaptor protein allowing DNA sensors recognizing exogenous cytosolic DNA to activate the type I interferon signaling cascade. In terms of EBV tumorigenicity, the role of STING remains elusive. Here we showed that treatment with the STING inhibitor, C-176, suppressed EBV-induced transformation in peripheral blood mononuclear cells. In an EBV-LPD mouse model, C-176 treatment also inhibited tumor formation and prolonged survival. Treatment with B cells alone did not affect EBV transformation, but suppression of EBV-induced transformation was observed in the presence of T cells. Even without direct B cell-T cell contact in a transwell system, the inhibitor reduced the transformation activity, indicating that intercellular communication by humoral factors was critical to prevent EBV-induced transformation. These findings suggest that inhibition of STING signaling pathway with C-176 could be a new therapeutic target of EBV-LPD.

Calcium-dependent signalling in B-cell lymphomas.

Induced waves of calcium fluxes initiate multiple signalling pathways that play an important role in the differentiation and maturation of B-cells. Finely tuned transient Ca+2 fluxes from the endoplasmic reticulum in response to B-cell receptor (BCR) or chemokine receptor activation are followed by more sustained calcium influxes from the extracellular environment and contribute to the mechanisms responsible for the proliferation of B-cells, their migration within lymphoid organs and their differentiation. Dysregulation of these well-balanced mechanisms in B-cell lymphomas results in uncontrolled cell proliferation and resistance to apoptosis. Consequently, several cytotoxic drugs (and anti-proliferative compounds) used in standard chemotherapy regimens for the treatment of people with lymphoma target calcium-dependent pathways. Furthermore, ~10% of lymphoma associated mutations are found in genes with functions in calcium-dependent signalling, including those affecting B-cell receptor signalling pathways. In this review, we provide an overview of the Ca2+-dependent signalling network and outline the contribution of its key components to B cell lymphomagenesis. We also consider how the oncogenic Epstein-Barr virus, which is causally linked to the pathogenesis of a number of B-cell lymphomas, can modify Ca2+-dependent signalling.

IGFBP7-AS1 is a p53-responsive long noncoding RNA downregulated by Epstein-Barr virus that contributes to viral tumorigenesis.

Epstein-Barr virus (EBV) is closely related to the development of several malignancies, such as B-cell lymphoma (B-CL), by the mechanism through which these malignancies develop remains largely unknown. We previously observed downregulation of the long noncoding RNA (lncRNA) IGFBP7-AS1 in response to EBV infection. However, the role of IGFBP7-AS1 in EBV-associated cancers has not been clarified. Here, we found that expression of IGFBP7-AS1, as well as its sense gene IGFBP7, is decreased in EBV-positive B-CL cells and clinical tissues. IGFBP7-AS1 stabilizes IGFBP7 mRNA by forming a duplex based on their overlapping regions. The tumour suppressor p53 transcriptionally activates IGFBP7-AS1 expression by binding to the promoter region of the lncRNA gene. The IGFBP7-AS1 expression is able to be rescued in EBV-positive cells in wild-type (wt) p53-dependent manner. IGFBP7-AS1 inhibits the proliferation and promotes the apoptosis of B-CL cells. Moreover, tumorigenic properties due to the depletion of IGFBP7-AS1 were restored by exogenous expression of IGFBP7 or wt-p53. Furthermore, the functional p53/IGFBP7-AS1/IGFBP7 axis facilitates apoptosis by suppressing the production and secretion of the NPPB signal peptide and further regulating the cGMP-PKG signalling pathway. This study demonstrates that EBV promotes tumorigenesis, particularly in B-CL progression, by downregulating the novel p53-responsive lncRNA IGFBP7-AS1.

SARS-CoV-2 Infection and Antibody Response in a Symptomatic Cat from Italy with Intestinal B-Cell Lymphoma.

Since the coronavirus disease (COVID-19) pandemic was first identified in early 2020, rare cases of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in pet cats have been reported worldwide. Some reports of cats with SARS-CoV-2 showed self-limiting respiratory or gastrointestinal disease after suspected human-to-feline transmission via close contact with humans with SARS-CoV-2. In the present study, we investigated a cat with SARS-CoV-2 that was presented to a private animal clinic in Northern Italy in May 2020 in a weak clinical condition due to an underlying intestinal B-cell lymphoma. The cat developed signs of respiratory tract disease, including a sneeze, a cough and ocular discharge, three days after an oropharyngeal swab tested positive for SARS-CoV-2 viral RNA using two real-time reverse transcriptase polymerase chain reaction (RT-qPCR) assays for the envelope (E) and RNA-dependent RNA polymerase (RdRp) gene. Thus, SARS-CoV-2 viral RNA was detectable prior to the onset of clinical signs. Five and six months after positive molecular results, the serological testing substantiated the presence of a SARS-CoV-2 infection in the cat with the detection of anti-SARS-CoV-2 receptor binding domain (RBD) immunoglobulin (IgG) antibodies and neutralizing activity in a surrogate virus neutralization assay (sVNT). To the best of our knowledge, this extends the known duration of seropositivity of SARS-CoV-2 in a cat. Our study provides further evidence that cats are susceptible to SARS-CoV-2 under natural conditions and strengthens the assumption that comorbidities may play a role in the development of clinical disease.

Pathologically Relevant Mouse Models for Epstein-Barr Virus-Associated B Cell Lymphoma.

The Epstein-Barr virus (EBV) is endemic in humans and can efficiently transform infected B cells under some circumstances. If an EBV carrier experiences immune suppression, EBV+ B cells can turn into lymphoblasts and exhibit growth expansion that may cause lymphoproliferative diseases which often develop into lymphoma. Our immune system conducts surveillance for EBV+ B cells in order to block spontaneous tumor formation. Here, we summarize the EBV products involved in tumorigenesis, EBV-associated lymphomas, and pathologically relevant mouse models. Preclinical mouse models for a range of EBV-associated diseases not only clear the path to new therapeutic approaches but also aid in our understanding of the nature of lymphomagenesis and immune surveillance.

Usefulness of Plasma SARS-CoV-2 RNA Quantification by Droplet-based Digital PCR to Monitor Treatment Against COVID-19 in a B-cell Lymphoma Patient.

We report the case of an HIV-1-infected patient, treated with anti-CD20 monoclonal antibody for a B-cell lymphoma previously treated by autologous stem cell transplant. He suffered from chronic COVID19 and we monitored by plasma SARS-CoV-2 RNA by highly sensitive droplet-based digital PCR technology (ddPCR). Under tocilizumab therapy and despite a first clinical improvement biologically associated with decreasing inflammatory markers, a slight increase of SARS-CoV-2 RNAaemia quantified by ddPCR was highlighted, confirming the absence of viral efficacy of this treatment and predicting the subsequent observed deterioration. As expected, his complete recovery, finally achieved after COVID-19 convalescent plasmatherapy, strictly paralleled plasma SARS-CoV-2 RNA clearance. With these results, we confirmed the interest of SARS-CoV-2 RNAaemia monitoring by ddPCR in COVID-19 patients, particularly during treatment, and firstly showed that this new and specific biomarker could be helpful to select eligible patient for anti-IL6 receptors therapy considering the variable levels of efficacy recently observed with such therapy.

Oncolytic virotherapy-mediated anti-tumor response: a single-cell perspective.

Talimogene laherparepvec (T-VEC) is a genetically modified herpes simplex 1 virus (HSV-1) approved for cancer therapy. We investigate its effect on the clinical, histological, single-cell transcriptomic, and immune repertoire level using repeated fine-needle aspirates (FNAs) of injected and noninjected lesions in primary cutaneous B cell lymphoma (pCBCL). Thirteen patients received intralesional T-VEC, 11 of which demonstrate tumor response in the injected lesions. Using single-cell sequencing of the FNAs, we identify the malignant population and separate three pCBCL subtypes. Twenty-four hours after the injection, we detect HSV-1T-VEC transcripts in malignant and nonmalignant cells of the injected lesion but not of the noninjected lesion. Oncolytic virotherapy results in a rapid eradication of malignant cells. It also leads to interferon pathway activation and early influx of natural killer cells, monocytes, and dendritic cells. These events are followed by enrichment in cytotoxic T cells and a decrease of regulatory T cells in injected and noninjected lesions.

Clinical Characteristics of Hemophagocytic Lymphohistiocytosis Associated with Non-Hodgkin B-Cell Lymphoma: A Multicenter Retrospective Study.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) associated with B-cell lymphoma is a highly aggressive disease with unclear clinical features and has no standard treatment. PATIENTS AND METHODS: We analyzed the clinical characteristics of 31 patients from two individual centers. RESULTS: The median overall survival was only 1.5 months. Both univariate and multivariate analyses, based on lymphoma or HLH-related characteristics, revealed that patients with high Epstein-Barr virus (EBV) DNA load and ≥ 2 extranodal lesions, or hypofibrinogenemia, respectively, showed significantly poorer overall survival. Interestingly, some patients with high EBV DNA load had EBV-positive natural killer (NK) and/or T cells, which may be related to the coexistence of immunodeficiency and/or chronic active EBV infection. Molecular genetics examination confirmed that 47.4% (9/19) of patients had complex karyotypes, 37.5% (3/8) of patients had TP53 deletions, and 21.34% (3/14) of patients had TP53 mutation or alteration of malignancy-related pathways, including BCR/NF-κB, JAK-STAT, and epigenetic regulatory pathways, which may provide clues to choose targets for therapy. Treatment regimens containing etoposide, anti-CD20 monoclonal antibodies, or anthracyclines improved patient prognosis (P = .0183, .025, and .0436, respectively). Patients with infections had significantly shorter survival than those without infections (P = .00019). CONCLUSION: The patients' performance status, number of extranodal lesions, high EBV DNA load, and hypofibrinogenemia are poor prognostic factors for HLH associated with B-cell lymphoma. Molecular genetic high-risk factors are of particular importance because these factors can provide information for prognosis prediction, treatment decisions, and disease surveillance.

Development of an in situ hybridization assay using an AS1 probe for detection of bovine leukemia virus in BLV-induced lymphoma tissues.

Enzootic bovine leukosis (EBL) is a malignant B cell lymphoma caused by infection with bovine leukemia virus (BLV). Histopathological examination is commonly used for diagnosis of the disease, but observation of lymphoma alone does not confirm EBL because cattle may be affected by sporadic forms of lymphoma that are not associated with BLV. Detection of BLV in tumor cells can be definitive evidence of EBL, but currently, there is no technique available for such a purpose. In this study, we focused on a viral non-coding RNA, AS1, and developed a novel in situ hybridization assay for the detection of BLV from formalin-fixed paraffin-embedded (FFPE) tissues. RNA-seq analysis revealed that all examined B lymphocytes derived from clinical EBL abundantly expressed AS1 RNA, indicating a possible target for detection. The in situ hybridization assay using an AS1 probe clearly detected AS1 RNA in fetal lamb kidney cells persistently infected with BLV. The utility of this assay in clinical samples was assessed using three EBL-derived lymph node specimens and one BLV-negative specimen, and AS1 RNA was detected specifically in the EBL-derived tissues. These results suggest that AS1 RNA is a useful target for the detection of BLV from FFPE specimens of tumor tissues. This technique is expected to become a powerful tool for EBL diagnosis.

High-grade B-Cell Lymphoma With MYC, BCL2, and/or BCL6 Translocations/Rearrangements: Clinicopathologic Features of 51 Cases in a Single Institution of South China.

Double-hit/triple-hit lymphomas (DH/THLs) are high-grade B-cell lymphomas with MYC and BCL2 rearrangements and/or BCL6 rearrangements, which have poor outcomes after standard chemoimmunotherapy. This retrospective study analyzed 51 patients (range, 19 to 82 y) diagnosed from 2016 to 2019 and treated for DH/THL (n=34 MYC/BCL6 DHL, n=14 MYC/BCL2 DHL, n=3 THL) at one institution in South China. Extranodal lesions occurred in 32 patients (62.7%), more frequently in MYC/BCL6 DHL (22/34, 64.7%) than in MYC/BCL2 DHL (7/14, 50%). The most common extranodal sites were the stomach (8/32, 25.0%) and intestine (5/32, 15.6%). Most patients (33/45, 73.3%) presented with Ann Arbor stage III/IV. Interestingly, 14.3% (4/28) of MYC/BCL6 DHL tumors showed diffuse, medium-intensity CD30 expression. Epstein-Barr virus-encoded RNA was positive in 3 cases, all MYC/BCL6 DHL. Among 48 patients (94.1%) with follow-up data, 18 (37.5%) died owing to the disease, and the median survival was 5.5 months. Germinal center B cells were observed more frequently in MYC/BCL2 DHL (14/14, 100.0%) than in MYC/BCL6 DHL (15/34, 44.1%; P<0.001). Bone marrow involvement tended to lower overall survival (OS) (P=0.033). No association was observed between stage, B symptoms, lactate dehydrogenase levels, and central nervous system involvement and OS. A total of 25 patients (25/47, 53.2%) with previous hepatitis B virus (HBV) infections had significantly poorer OS (P=0.014). Chronic HBV infection was positively correlated with MYC/BCL6 DHL (r=0.317, P=0.030). Compared with DH/THL in western countries, the disease in South China has distinct characteristics with a higher prevalence of MYC/BCL6 DHL. We speculate that HBV is important in DH/THL tumorigenesis. These findings might provide clues for novel treatment strategies.