The Epstein-Barr Virus (EBV) in T Cell and NK Cell Lymphomas: Time for a Reassessment

Targeted therapy with nanatinostat and valganciclovir in recurrent EBV-positive lymphoid malignancies: a phase 1b/2 study

Lymphomas are not infrequently associated with the Epstein-Barr virus (EBV), and EBV positivity is linked to worse outcomes in several subtypes. Nanatinostat is a class-I selective oral histone deacetylase inhibitor that induces the expression of lytic EBV BGLF4 protein kinase in EBV+ tumor cells, activating ganciclovir via phosphorylation, resulting in tumor cell apoptosis. This phase 1b/2 study investigated the combination of nanatinostat with valganciclovir in patients aged ≥18 years with EBV+ lymphomas relapsed/refractory to ≥1 prior systemic therapy with no viable curative treatment options. In the phase 1b part, 25 patients were enrolled into 5 dose escalation cohorts to determine the recommended phase 2 dose (RP2D) for phase 2 expansion. Phase 2 patients (n = 30) received RP2D (nanatinostat 20 mg daily, 4 days per week with valganciclovir 900 mg orally daily) for 28-day cycles. The primary end points were safety, RP2D determination (phase 1b), and overall response rate (ORR; phase 2). Overall, 55 patients were enrolled (B-non-Hodgkin lymphoma [B-NHL], [n = 10]; angioimmunoblastic T-cell lymphoma-NHL, [n = 21]; classical Hodgkin lymphoma, [n = 11]; and immunodeficiency-associated lymphoproliferative disorders, [n = 13]). The ORR was 40% in 43 evaluable patients (complete response rate [CRR], 19% [n = 8]) with a median duration of response of 10.4 months. For angioimmunoblastic T-cell lymphoma-NHL (n = 15; all refractory to the last prior therapy), the ORR/CRR ratio was 60%/27%. The most common adverse events were nausea (38% any grade) and cytopenia (grade 3/4 neutropenia [29%], thrombocytopenia [20%], and anemia [20%]). This novel oral regimen provided encouraging efficacy across several EBV+ lymphoma subtypes and warrants further evaluation; a confirmatory phase 2 study (NCT05011058) is underway. This phase 1b/2 study is registered at www.clinicaltrials.gov as #NCT03397706.

Exploration and analysis of differentially expressed genes in Epstein-Barr virus negative and positive plasmablastic lymphoma

OBJECTIVES

Plasmablastic lymphoma (PBL) is a subtype of diffuse large B-cell lymphoma (DLBCL) often associated with Epstein-Barr virus (EBV) infection. Despite recent advances in treatment, PBL still has a poor prognosis. EBV is listed as one of the human tumor viruses that may cause cancer, and is closely related to the occurrence of some nasopharyngeal carcinoma (NPC), lymphoma and 10% of gastric cancer (GC). It is very important to explore the differentially expressed genes (DEGs) between EBV-positive and EBV-negative PBL. Through bioinformatics analysis of DEGs between EBV-positive PBL and EBV-negative PBL, we gain a deeper understanding of the pathogenesis of EBV-positive PBL.

METHODS

We selected the GSE102203 data set, and screened the DEGs between EBV-positive PBL and EBV-negative PBL. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were applied. The protein-protein interaction (PPI) network was constructed, and screened for the hub genes. Finally, Gene Set Enrichment Analysis (GSEA) was performed.

RESULTS

In EBV-positive PBL, the immune-related pathway is upregulated and Cluster of differentiation 27 (CD27) and programmed cell death-ligand 1 (PD-L1) are hub genes.

CONCLUSIONS

In EBV-positive PBL, EBV may affect tumorigenesis through activation of immune-related pathways and upregulation of CD27, PD-L1. Immune checkpoint blockers of CD70/CD27 and programmed cell death 1 (PD-1)/PD-L1 pathways may be one of the effective strategies for the treatment of EBV-positive PBL.

An update on viral-induced cutaneous lymphoproliferative disorders. CME Part I

Viral-induced cutaneous T-cell lymphomas are an uncommon group of lymphoproliferative disorders characterized by a viral infection of T and natural killer (NK) cells. This group of cutaneous T-cell lymphomas is more commonly encountered in Asians and Native Americans from Central and South America compared with Western populations. Viral-associated lymphoproliferative disorders include a spectrum of entities that range from nonneoplastic lesions, such as chronic active Epstein-Barr virus infection and infective dermatitis to malignant diseases, such as extranodal NK/T-cell lymphoma, hydroa vacciniforme-like T-cell lymphoma, and adult T-cell leukemia/lymphoma. This review article will focus on hydroa vacciniforme-like lymphoproliferative disorder, extranodal NK/T-cell lymphoma, adult T-cell leukemia/lymphoma, lymphomatoid granulomatosis, and Epstein-Barr virus-positive mucocutaneous ulcers. We will review the pathogenesis of these conditions and the challenges of making a timely diagnosis in early-stage disease and discuss the common clinicopathologic manifestations, mutational landscape, and approaches to treat these highly aggressive and frequently lethal types of lymphoma.

Follicular Helper T-Cell-derived Nodal Lymphomas: Study of Histomorphologic, Immunophenotypic, Clinical, and RHOA G17V Mutational Profile

The study was designed to review the demographic, clinical, and pathologic characteristics of follicular helper T cells (TFH)-derived nodal PTCL in India including angioimmunoblastic T-cell lymphoma (AITL), peripheral T-cell lymphoma (PTCL) with follicular helper T cell phenotype (P-TFH), and follicular T-cell lymphoma with additional immunohistochemistry (IHC) and RHOAG17V mutational analysis, as well as their impact on survival. This retrospective study included 88 cases of PTCL that were reclassified using IHC for TFH markers (PD1, ICOS, BCL6, and CD10) and dendritic-meshwork markers (CD21, CD23). Cases of TFH cell origin were evaluated for RHOAG17V mutation using Sanger sequencing and amplification-refractory mutation system-polymerase chain reaction (PCR) (validated using cloning and quantitative PCR) with detailed clinicopathologic correlation. Extensive re-evaluation with added IHC panel resulted in a total of 19 cases being reclassified, and the final subtypes were AITL (37 cases, 42%), PTCL-not otherwise specified (44, 50%), P-TFH (6, 7%), and follicular T-cell lymphoma (1, 1%). The presence of at least 2 TFH markers (>20% immunopositivity) determined the TFH origin. AITL patients tended to be male and showed increased presence of B-symptoms and hepatosplenomegaly. Histomorphology revealed that 92% of AITL cases had pattern 3 involvement. Sanger sequencing with conventional PCR did not yield any mutation, while RHOAG17V was detected by amplification-refractory mutation system-PCR in AITL (51%, P =0.027) and P-TFH (17%), which was validated with cloning followed by sequencing. Cases of RHOAG17V-mutant AITL had a worse Eastern Cooperative Oncology Group performance status initially but fared better in terms of overall outcome ( P =0.029). Although not specific for AITL, RHOAG17V mutation shows an association with diagnosis and requires sensitive methods for detection due to low-tumor burden. The mutant status of AITL could have prognostic implications and translational relevance.

Tumor resident, TRA anti-viral CDR3 chemical sequence motifs are associated with a better breast cancer outcome

While for certain cancers, such as cervical cancer, the link to viral infections is very strong and very clear, other cancers represent a history of links to viral infections that are either co-morbidities or drive the cancer in ways that are not yet fully understood, for example the "hit and run" possibility. To further understand the connection of viral infections and the progress of breast cancer, we identified the chemical features of known anti-viral, T-cell receptor alpha chain (TRA) complementarity determining region-3 (CDR3) amino acid sequences among the CDR3s of breast cancer patient TRA recombinations and assessed the association of those features with patient outcomes. The application of this novel paradigm indicated consistent associations of tumor-derived, anti-CMV CDR3 chemical sequence motifs with better breast cancer patient outcomes but did not indicate an opportunity to establish risk stratifications for other cancer types. Interestingly, breast cancer samples with no detectable TRA recombinations represented a better outcome than samples with the non-anti-CMV CDR3s, further adding to a rapidly developing series of results allowing a distinction between positive and possibly harmful cancer immune responses.

Plasma EBV-DNA and peripheral blood mononuclear cell EBV-DNA have disparate clinical relevance in patients with extranodal NK/T-cell lymphoma

BACKGROUND

Extranodal NK/T-cell lymphoma (ENKTCL) is an Epstein-Barr virus (EBV)-related hematological malignancy. The presence of EBV-DNA in peripheral blood is a widely used ENKTCL tumor marker. However, there is no consensus on the preferred blood specimen type for EBV testing. Furthermore, discordance between EBV-based and imaging-based disease assessments is common, and how to interpret this discordance is important.

METHOD

We retrospectively analyzed the data of ENKTCL patients in the Affiliated Cancer Hospital of Zhengzhou university and Sun Yat-sen University Cancer Center. All EBV-DNA and imaging-based disease assessment data were collected at diagnosis, during treatment, at the end of treatment, and during follow-up. We compared matched plasma EBV-DNA and peripheral blood mononuclear cell (PBMC) EBV-DNA and matched EBV-based and imaging-based assessments to uncover their clinical relevance.

RESULT

A total of 450 patients with adequate data were included, of whom 278 had plasma EBV-DNA data, 250 had PBMC EBV-DNA data, and 78 had matched plasma and PBMC EBV-DNA data. No significant correlations were found between PBMC and plasma EBV-DNA and between PBMC EBV-DNA and imaging-based assessment, but patients with positive PBMC EBV-DNA at diagnosis or intermittently/persistently positive PBMC EBV-DNA during follow-up had poorer survival. In contrast, plasma EBV-DNA strongly correlated with lymphoma status. Detectable pre- and post-treatment plasma EBV-DNA was associated with significantly worse survival. Patients with early-stage disease who had detectable plasma EBV-DNA at the end of treatment shared similar survival to those with advanced-stage disease, even if their imaging-based assessments were negative. For disease relapse monitoring, 78 (55.7%) episodes of relapse were detected by both imaging and plasma EBV-DNA; 58 (41.4%) detected by plasma EBV-DNA earlier than imaging, with a median time of 9.3 (0.3 - 37.8) months; and only 4 (2.9%) detected by plasma EBV-DNA later than imaging. The sensitivities of plasma EBV-DNA, PET/CT, and CT/MRI were 97.1%, 76.8%, and 45.1%, respectively, and their specificities were 91.7%, 84.2%, and 96.7%, respectively. Analysis of EBV kinetic patterns in EBV+/imaging- episodes revealed that relapse occurred only in patients with intermittently/persistently positive plasma EBV-DNA. Persistent plasma EBV+ was also seen in patients after autologous hematopoietic stem cell transplantation. Occasional EBV+ was not associated with relapse.

CONCLUSION

Plasma and PBMC EBV-DNA have different clinical relevance in ENKTCL patients. PBMC EBV-DNA does not correlate with imaging-based disease assessment. PBMC or even whole blood should not be used for response evaluation and relapse monitoring. However, PBMC EBV-DNA still has prognostic value. Plasma EBV-DNA is strongly related to tumor status and is not only a prognosticator at diagnosis and end of treatment, but also a sensitive marker in relapse monitoring compared to PET/CT and CT/MRI. The specificity of plasma EBV-DNA is relatively low, but when EBV-DNA kinetic patterns are considered, it can identify at-risk patients.

The role of virus infections in Sjögren’s syndrome

Primary Sjögren’s syndrome (pSS) is an autoimmune disease with a clinical picture of not only mainly exocrine gland involvement, with dryness symptoms, but also internal organ and systems involvement. The epithelial damage and releasing of antigens, which, in some circumstances, become autoantigens, underlay the pathogenesis of pSS. The activation of autoimmune processes in pSS leads to the hyperactivation of B cells with autoantibody production and other immunological phenomena such as hypergammaglobulinemia, production of cryoglobulins, or formation of extra-nodal lymphoid tissue. Among the risk factors for the development of this disease are viral infections, which themselves can activate autoimmune reactions and influence the host’s immune response. It is known that viruses, through various mechanisms, can influence the immune system and initiate autoimmune reactions. These mechanisms include molecular mimicry, bystander activation, production of superantigens—proteins encoded by viruses—or a programming to produce viral cytokines similar to host cytokines such as, e.g., interleukin-10. Of particular importance for pSS are viruses which not only, as expected, activate the interferon pathway but also play a particular role, directly or indirectly, in B cell activation or present tropism to organs also targeted in the course of pSS. This article is an attempt to present the current knowledge of the influence specific viruses have on the development and course of pSS.

Epstein-Barr Virus (EBV) Is Mostly Latent and Clonal in Angioimmunoblastic T Cell Lymphoma (AITL)

The Epstein-Barr virus (EBV) is associated with angioimmunoblastic T cell lymphoma (AITL), a peripheral T lymphoma of poor prognosis in at least 90% of cases. The role of EBV in this pathology is unknown. Using next-generation sequencing, we sequenced the entire EBV genome in biopsies from 18 patients with AITL, 16 patients with another EBV-associated lymphoma, and 2 controls. We chose an EBV target capture method, given the high specificity of this technique, followed by a second capture to increase sensitivity. We identified two main viral strains in AITL, one of them associated with the mutations BNRF1 S542N and BZLF1 A206S and with mutations in the EBNA-3 and LMP-2 genes. This strain was characterized in patients with short post-diagnosis survival. The main mutations found during AITL on the most mutated latency or tegument genes were identified and discussed. We showed that the virus was clonal in all the AITL samples, suggesting that it may be involved in this pathology. Additionally, EBV was latent in all the AITL samples; for one sample only, the virus was found to be latent and probably replicative, depending on the cells. These various elements support the role of EBV in AITL.

A preclinical model of peripheral T-cell lymphoma GATA3 reveals DNA damage response pathway vulnerability

Peripheral T-cell lymphoma (PTCL) represents a rare group of heterogeneous diseases in urgent need of effective treatments. A scarcity of disease-relevant preclinical models hinders research advances. Here, we isolated a novel mouse (m)PTCL by serially transplanting a lymphoma from a germinal center B-cell hyperplasia model (Cγ1-Cre Blimp1fl/fl ) through immune-competent mice. Lymphoma cells were identified as clonal TCRβ+ T-helper cells expressing T-follicular helper markers. We also observed coincident B-cell activation and development of a de novo B-cell lymphoma in the model, reminiscent of B-cell activation/lymphomagenesis found in human PTCL. Molecular profiling linked the mPTCL to the high-risk "GATA3" subtype of PTCL, showing GATA3 and Th2 gene expression, PI3K/mTOR pathway enrichment, hyperactivated MYC, and genome instability. Exome sequencing identified a human-relevant oncogenic β-catenin mutation possibly involved in T-cell lymphomagenesis. Prolonged treatment responses were achieved in vivo by targeting ATR in the DNA damage response (DDR), a result corroborated in PTCL cell lines. This work provides mechanistic insight into the molecular and immunological drivers of T-cell lymphomagenesis and proposes DDR inhibition as an effective and readily translatable therapy in PTCL.

EBV+ lymphoproliferative diseases: opportunities for leveraging EBV as a therapeutic target

Epstein-Barr virus (EBV) is a ubiquitous human tumor virus, which contributes to the development of lymphoproliferative disease, most notably in patients with impaired immunity. EBV-associated lymphoproliferation is characterized by expression of latent EBV proteins and ranges in severity from a relatively benign proliferative response to aggressive malignant lymphomas. The presence of EBV can also serve as a unique target for directed therapies for the treatment of EBV lymphoproliferative diseases, including T cell-based immune therapies. In this review, we describe the EBV-associated lymphoproliferative diseases and particularly focus on the therapies that target EBV.

Epstein-Barr virus-induced natural killer/T cell lymphoma arising in tonsil and cervical node tissue

Infection with Epstein-Barr virus (EBV) has been linked to approximately 10%-15% of lymphomas diagnosed in the USA, including a small percentage of Natural Killer (NK)/T cell lymphomas, which are clinically aggressive, respond poorly to chemotherapy and have a shorter survival. Here, we present a case of a patient found to have EBV-induced NK/T cell lymphoma from a chronic EBV infection. While the EBV most commonly infects B cells, it can infect NK/T cells, and it is important for the clinician to be aware of the potential transformation to lymphoma as it is clinically aggressive, warranting early recognition and treatment. NK/T cell lymphoma is a unique type of non-Hodgkin's lymphoma that is almost always associated with EBV. The disease predominantly localises in the upper aerodigestive tract, most commonly in the nose.

Comparison of tumor mutation burden of 300 various non-Hodgkin lymphomas using panel based massively parallel sequencing

Background

Tumor mutation burden is an emerging biomarker for immunotherapy. Although several clinical trials for immunotherapy in lymphoma have been carried out, the mutation burden of various lymphomas is not well known yet. Thus, the objective of this study was to compare tumor mutation burden of various non-Hodgkin lymphomas using panel based massively parallel sequencing.

Methods

We conducted 405 gene panel based massively parallel sequencing of 300 non-Hodgkin lymphomas and investigate the number of SNV/Indel in each lymphoma.

Results

The number of SNV/Indel was higher in mature B-cell lymphoma than in mature T- and NK-cell lymphoma. (P < 0.001) The number of SNV/Indel in primary mediastinal large B-cell lymphoma and primary diffuse large B-cell lymphoma of the central nervous system was the highest, which was significantly higher than that in diffuse large B-cell lymphoma, not otherwise specified (DLBCL NOS).(P = 0.030 and P = 0.008, respectively) The SNV/Indel number in EBV-positive DLBCL NOS was significantly lower than that in DLBCL NOS. (P = 0.048) Peripheral T-cell lymphoma, NOS showed no significant difference in the number of SNV/Indel from extranodal NK/T-cell lymphoma, nasal type (P = 0.942) or angioimmunoblastic T-cell lymphoma (P = 0.739). The number of SNV/Indel in anaplastic large cell lymphoma, ALK-positive was significantly lower than that in anaplastic large cell lymphoma, ALK-negative (P = 0.049). It was the lowest among all the lymphomas considered.

Conclusion

Various lymphomas have different mutation burdens. Thus, tumor mutation burden can be used as a promising biomarker for immunotherapy in lymphomas.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08695-7.

Molecular Properties and Therapeutic Targeting of the EBV-Encoded Receptor BILF1

The γ-herpesvirus Epstein-Barr Virus (EBV) establishes lifelong infections in approximately 90% of adults worldwide. Up to 1,000,000 people yearly are estimated to suffer from health conditions attributed to the infection with this virus, such as nasopharyngeal and gastric carcinomas as well as several forms of B, T and NK cell lymphoma. To date, no EBV-specific therapeutic option has reached the market, greatly reducing the survival prognoses of affected patients. Similar to other herpesviruses, EBV encodes for a G protein-coupled receptor (GPCR), BILF1, affecting a multitude of cellular signaling pathways. BILF1 has been identified to promote immune evasion and tumorigenesis, effectively ensuring a life-long persistence of EBV in, and driving detrimental health conditions to its host. This review summarizes the epidemiology of EBV-associated malignancies, their current standard-of-care, EBV-specific therapeutics in development, GPCRs and their druggability, and most importantly consolidates the findings of over 15 years of research on BILF1 in the context of EBV-specific drug development. Taken together, BILF1 constitutes a promising target for the development of novel EBV-specific therapeutics.

The bidirectional increased risk of B-cell lymphoma and T-cell lymphoma

Lymphoma survivors have a significantly higher risk of developing second primary lymphoma than the general population; however, bidirectional risks of developing B- and T-cell lymphomas (BCL; TCL) specifically are less well understood. We used population-based cancer registry data to estimate the subtype-specific risks of second primary lymphoma among patients with first BCL (n=288,478) or TCL (n=23,747). We observed nearly five-fold increased bidirectional risk between BCL and TCL overall (TCL following BCL: standardized incidence ratio [SIR]=4.7, 95% confidence interval [CI]=4.2-5.2; BCL following TCL: SIR=4.7, 95%CI=4.1-5.2), but the risk varied substantially by lymphoma subtype. The highest SIRs were observed between Hodgkin lymphoma (HL) and peripheral T-cell lymphoma-not otherwise specified (PTCL-NOS) (PTCL-NOS following HL: SIR=27.5, 95%CI=18.4-39.4; HL following PTCL-NOS: SIR=31.6, 95%CI=17.3-53.0). Strikingly elevated risks also were notable for angioimmunoblastic T-cell lymphoma (AITL) and diffuse large B-cell lymphoma (DLBCL) (AITL following DLBCL: SIR=9.7, 95%CI=5.7-15.5; DLBCL following AITL: SIR=15.3, 95%CI=9.1-24.2). These increased risks were strongest within the first year following diagnosis but remained persistently elevated even at ≥5 years. In contrast, SIRs were <5 for all associations of TCL with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and follicular lymphoma (FL). These patterns support etiologic heterogeneity among lymphoma subtypes and provide further insights into lymphomagenesis.

Hepatic involvement by T-cell neoplasms: a clinicopathologic study of 40 cases

Hepatic involvement by a T-cell neoplasm is rare and often challenging to diagnose in liver biopsies. We collected 40 cases of T-cell neoplasms diagnosed in the liver from five large academic institutions to assess the clinicopathologic features. The patients included 11 women and 29 men, with a median age of 54 (range: 2-75) years and a high mortality rate (31/37, 83.8%). Fourteen (35%) patients were diagnosed with hepatosplenic T-cell lymphoma (HSTCL), 13 (32.5%) peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), and 13 (32.5%) other types of T-cell neoplasms. Patients with HSTCL were much younger and had worse survival than PTCL-NOS and other T-cell neoplasms (P < 0.05). On imaging studies, 20 cases (50%) showed abnormalities, including 10 with mass lesions that correlated with normal or cholestatic pattern enzyme elevation. Histomorphological analysis revealed four main patterns; with the exception of mass forming lesions (pattern 4; n = 8), cases with sinusoidal predominant (pattern 1; n = 12), portal predominant with sinusoidal infiltrates (pattern 2; n = 13) or lobular aggregates (pattern 3; n = 5) demonstrated small to medium lymphocytes resembling a reactive/inflammatory process. In addition, we described two cases of T-cell large granular lymphocytic leukemia that mimicked HSTCL, and a case of aggressive post-transplant lymphoproliferative disorder that developed after chronic Epstein-barr virus (EBV) infection, suggesting the importance of EBV testing in some lymphoma cases. As the largest cohort of T-cell neoplasms in liver, our study provides critical data on disease frequency, distribution, and clinicopathologic features that are essential for accurate diagnosis.

Extranodal NK/T-cell lymphoma, nasal type without evidence of EBV infection

Extranodal natural killer/T cell lymphoma-nasal type (EN-NK/T-NT) is extremely rare in Western countries; however, it is the most common subtype of peripheral T cell lymphoma in China. Despite this, there are a limited number of clinicopathological research studies on Epstein-Barr virus (EBV)-negative EN-NK/T-NTs. EBV-negative EN-NK/T-NT is a rare disease type, which has not been fully investigated. If other diagnostic criteria are met, such as the lesions being located predominantly in the upper aerodigestive tract, the presence of angiocentricity or angioinvasion, necrosis and expression of NK/T-cell phenotype, EN-NK/T-NT may be diagnosed, even if EBV is negative. In the present study, 99 cases of EN-NK/T-NTs were analyzed retrospectively, among which seven cases were EBV-negative EN-NK/T-NTs and selected for further investigation. In addition, the present study reviewed previously published research into EN-NK/T-NT, highlighting that EBV-negative EN-NK/T-NT is rare and that its geographical distribution is mainly in countries in Asia, Central America and South America. Patients with EBV-negative EN-NK/T-NT were all of Chinese ethnicity, with a median age of 32 years and primarily female. Furthermore, these patients shared similar clinicopathological characteristics (such as the tumor occurring mainly in the upper aerodigestive tract, the presence of vascular destruction, necrosis and cytotoxic phenotypes) to patients with EBV-positive EN-NK/T-NT. Immunohistochemistry and molecular analysis results indicated that tumor cells were primarily of NK or cytotoxic T origin; however, EBV-encoded small RNAs were not detected in any of these cases. Among the immunochemistry markers, T-bet was statistical significantly different between EBV-positive and -negative cases. Fluorescence in situ hybridization was also performed in two EBV-negative cases, including one case with a co-deletion of 6q21 and PR/SET domain 1 genes. There was only available follow-up data in 3/5 patients who survived for 37–113 months (median, 40 months). As EN-NK/T-NT can be diagnosed, even when EBV is negative, awareness of this subtype may prevent misdiagnosis or delayed diagnosis.

CD21 (Complement Receptor 2) Is the Receptor for Epstein-Barr Virus Entry into T Cells

Epstein-Barr virus (EBV) is associated with a number of T-cell diseases, including some peripheral T-cell lymphomas, hemophagocytic lymphohistiocytosis, and chronic active EBV disease. The tropism of EBV for B cells and epithelial cell infection has been well characterized, but infection of T cells has been minimally explored. We have recently shown that the EBV type 2 (EBV-2) strain has the unique ability to infect mature T cells. Utilizing an ex vivo infection model, we sought to understand the viral glycoprotein and cellular receptor required for EBV-2 infection of T cells. Here, using a neutralizing-antibody assay, we found that viral gp350 and complement receptor 2 (CD21) are required for CD3⁺ T-cell infection. Using the HB5 anti-CD21 antibody clone but not the Bly-4 anti-CD21 antibody clone, we detected expression of CD21 on both CD4⁺ and CD8⁺ T cells, with the highest expression on naive CD4 and CD8⁺ T-cell subsets. Using CRISPR to knock out CD21, we demonstrated that CD21 is necessary for EBV entry into the Jurkat T-cell line. Together, these results indicate that EBV uses the same viral glycoprotein and cellular receptor for both T- and B-cell infection.IMPORTANCE Epstein-Barr virus (EBV) has a well-described tropism for B cells and epithelial cells. Recently, we described the ability of a second strain of EBV, EBV type 2, to infect mature peripheral T cells. Using a neutralizing antibody assay, we determined that EBV uses the viral glycoprotein gp350 and the cellular protein CD21 to gain entry into mature peripheral T cells. CRISPR-Cas9 deletion of CD21 on the Jurkat T-cell line confirmed that CD21 is required for EBV infection. This study has broad implications, as we have defined a function for CD21 on mature peripheral T cells, i.e., as a receptor for EBV. In addition, the requirement for gp350 for T-cell entry has implications for EBV vaccine studies currently targeting the gp350 glycoprotein to prevent EBV-associated diseases.

A Systematic Approach to the Cutaneous Lymphoid Infiltrates: A Clinical, Morphologic, and Immunophenotypic Evaluation

CONTEXT.—

The evaluation of cutaneous lymphoid infiltrates, both neoplastic and inflammatory, occurs very frequently in routine dermatopathologic examination and consultation practices. The "tough" cutaneous lymphoid infiltrate is feared by many pathologists; skin biopsies are relatively small, whereas diagnostic possibilities are relatively broad. It is true that cutaneous lymphomas can be difficult to diagnose and that in many circumstances multiple biopsies are required to establish a correct diagnostic interpretation. As a reminder, one should understand that low-grade cutaneous lymphomas are indolent disorders that usually linger for decades and that therapy does not result in disease cure. It is also important to remember that in most circumstances, those patients will die from another process that is completely unrelated to a diagnosis of skin lymphoma (even in the absence of specific therapy).

OBJECTIVE.—

To use a clinicopathologic, immunophenotypic, and molecular approach in the evaluation of common lymphocytic infiltrates.

DATA SOURCES.—

An in-depth analysis of updated literature in the field of cutaneous lymphomas was done, with particular emphasis on updated terminology from the most recent World Health Organization classification of skin and hematologic tumors.

CONCLUSIONS.—

A diagnosis of cutaneous lymphoid infiltrates can be adequately approached using a systematic scheme following the proposed ABCDE system. Overall, cutaneous T- and B-cell lymphomas are rare and "reactive" infiltrates are more common. Evaluation of lymphoid proliferations should start with a good sense of knowledge of the clinical presentation of the lesions, the clinical differential considerations, and a conscientious and appropriate use of immunohistochemistry and molecular tools.

Memory and Memory-Like NK Cell Responses to Microbial Pathogens

NK cells are cytotoxic lymphocytes that provide systemic defense against pathogens and malignancy. Although historically considered cells of the innate immune system, NK cells are now known to be capable of memory or memory-like immune responses in certain settings. Memory NK responses were initially reported over a decade ago in studies involving mouse models of cytomegalovirus infection and delayed-type hypersensitivity reactions to chemical haptens and viral antigens. Since then, a growing body of literature suggests that memory or memory-like NK cell responses may occur in a broader range of immunological settings, including in response to various viral and bacterial infections, and some immunization protocols. Memory-like NK cell responses have also now been reported in humans and non-human primates. Here, we summarize recent studies demonstrating memory or memory-like responses by NK cells in settings of infection and immunization against infectious agents.

Breaking Down the Barriers to Define and Treat NK/T Cell Lymphoma

In this issue of Cancer Cell, Xiong and colleagues describe the genomic and transcriptional landscape of natural killer/T cell lymphoma (NKTCL), a rare form of non-Hodgkin's lymphoma associated with EBV infection. They divide NKTCL into molecularly defined subtypes that could inform therapeutic strategies for patients with this deadly disease.

Epstein-Barr Virus Infection in the Development of Neurological Disorders

Epstein-Barr Virus (EBV) is a ubiquitous human herpesvirus that contributes to the etiology of diverse human cancers and auto-immune diseases. EBV establishes a relatively benign, long-term latent infection in over 90 percent of the adult population. Yet, it also increases risk for certain cancers and auto-immune disorders depending on complex viral, host, and environmental factors that are only partly understood. EBV latent infection is found predominantly in memory B-cells, but the natural infection cycle and pathological aberrations enable EBV to infect numerous other cell types, including oral, nasopharyngeal, and gastric epithelia, B-, T-, and NK-lymphoid cells, myocytes, adipocytes, astrocytes, and neurons. EBV infected cells, free virus, and gene products can also be found in the CNS. In addition to the direct effects of EBV on infected cells and tissue, the effect of chronic EBV infection on the immune system is also thought to contribute to pathogenesis, especially auto-immune disease. Here, we review properties of EBV infection that may shed light on its potential pathogenic role in neurological disorders.

Prevalence of Epstein-Barr virus (EBV) in Iranian Breast Carcinoma Patients

Introduction:

Breast cancer (BC) is the most common malignancy affecting females worldwide. Various risk factors play a role in the developing of BC. Infectious agents like viruses have been proposed for this cancer and Epstein-Barr virus (EBV) is a widely researched candidate virus. This study detects the presence of EBV-DNA in breast cancer patients.

Methods:

The study was conducted on 59 formalin-fixed paraffin-embedded (FFPE) tissue blocks samples of women with breast carcinoma and 11 non-neoplastic breast controls. The DNA was extracted for all the samples. Then detection of EBNA1 EBV was done by polymerase chain reaction (PCR).

Results:

EBV was detected in 6.7% (4/59) of patients while all breast control samples were negative. All patients with positive EBV-DNA were high tumor grades (II, and III). Also, they had a low level of educations.

Conclusions:

According to our findings, it can be suggested that EBV may have a potential role in breast cancer development. However, this study provides substantial but not conclusive evidence for the involvement of viruses in BC disease development. Therefore, future investigations are needed to elucidate the exact role of EBV in breast cancer.

Extranodal NK/T-cell lymphoma in Tunisia: clinicopathological features, immunophenotype and EBV infection

BACKGROUND

Extranodal NK/T-cell lymphomas (ENKTL) are rare non-Hodgkin's lymphomas with aggressive clinical behavior. ENKTL are frequently associated with the Epstein-Barr virus (EBV). Data on ENKTL in Africa and Arab world are extremely limited. The study investigated the clinicopathological characteristics, EBV infection, and immunophenotype of ENKTL in Tunisia. We conducted a retrospective study of ENKTL. Main clinicopathological features were reported. The expression of CD3, CD4, CD5, CD8, CD20, CD56, CD57, and Granzyme B were analyzed by immunohistochemistry. EBV infection was detected by IHC (LMP-1) and Epstein-Barr encoding region (EBER1/2) in situ hybridization.

RESULTS

A total of nine ENKTL were identified (mean age of 48 years and male-to-female ratio of 8:1). There were five nasal ENKTL, and the remaining four cases had extranasal involvement (palate, sub-mandibular gland, skin, and soft tissues of the ankle). The histopathology showed a lymphoid and pleomorphic proliferation characterized by images of angiocentrism. Strong and diffuse CD3 expression was observed in all cases. Tumor cells exhibited an expression of CD5 (two cases), CD8 (three cases), CD56 (six cases), CD57 (three cases), and Granzyme B (eight cases). All ENKTL cases were EBV-associated. Overall 5-year survival rate was 57%. Although six ENKTL were diagnosed at early clinical stages, the prognosis was unfavorable and associated with patient death in three cases.

CONCLUSIONS

ENKTL are exceptional in Tunisia with unfavorable outcome. Histopathological diagnosis remains challenging in clinical practice. However, a careful histopathological examination combined with a correct interpretation of immunohistochemistry and in situ hybridization results refines the ENKTL diagnosis.

EBV-Associated Lymphoproliferative Disorders: Update in Classification

Although about 90% of the world's population is infected by EBV only a small subset of the related infections result in neoplastic transformation. EBV is a versatile oncogenic agent involved in a multitude of hematopoietic, epithelial, and mesenchymal neoplasms, but the precise role of EBV in the pathogenesis of many of the associated lymphoid/histiocytic proliferations remains hypothetical or not completely understood. Additional studies and use of evolving technologies such as high-throughput next-generation sequencing may help address this knowledge gap and may lead to enhanced diagnostic assessment and the development of potential therapeutic interventions.

High-Throughput Sequence Analysis of Peripheral T-Cell Lymphomas Indicates Subtype-Specific Viral Gene Expression Patterns and Immune Cell Microenvironments

Certain peripheral T-cell lymphomas (PTCLs) have been associated with viral infection, particularly infection with Epstein-Barr virus (EBV). However, a comprehensive virome analysis across PTCLs has not previously been reported. Here we utilized published whole-transcriptome RNA sequencing (RNA-seq) data sets from seven different PTCL studies and new RNA-seq data from our laboratory to screen for virus association, to analyze viral gene expression, and to assess B- and T-cell receptor diversity paradigms across PTCL subtypes. In addition to identifying EBV in angioimmunoblastic T-cell lymphoma (AITL) and extranodal NK/T-cell lymphoma (ENKTL), two PTCL subtypes with well-established EBV associations, we also detected EBV in several cases of anaplastic large-cell lymphoma (ALCL), and we found evidence of infection by the oncogenic viruses Kaposi's sarcoma-associated herpesvirus and human T-cell leukemia virus type 1 in isolated PTCL cases. In AITLs, EBV gene expression analysis showed expression of immediate early, early, and late lytic genes, suggesting either low-level lytic gene expression or productive infection in a subset of EBV-infected B-lymphocyte stromal cells. Deconvolution of immune cell subpopulations demonstrated a greater B-cell signal in AITLs than in other PTCL subtypes, consistent with a larger role for B-cell support in the pathogenesis of AITL. Reconstructed T-cell receptor (TCR) and B-cell receptor (BCR) repertoires demonstrated increased BCR diversity in AITLs, consistent with a possible EBV-driven polyclonal response. These findings indicate potential alternative roles for EBV in PTCLs, in addition to the canonical oncogenic mechanisms associated with EBV latent infection. Our findings also suggest the involvement of other viruses in PTCL pathogenesis and demonstrate immunological alterations associated with these cancers.IMPORTANCE In this study, we utilized next-generation sequencing data from 7 different studies of peripheral T-cell lymphoma (PTCL) patient samples to globally assess viral associations, provide insights into the contributions of EBV gene expression to the tumor phenotype, and assess the unique roles of EBV in modulating the immune cell tumor microenvironment. These studies revealed potential roles for EBV replication genes in some PTCL subtypes, the possible role of additional human tumor viruses in rare cases of PTCLs, and a role for EBV in providing a unique immune microenvironmental niche in one subtype of PTCLs. Together, these studies provide new insights into the understudied role of tumor viruses in PTCLs.

Pathogenesis and biomarkers of natural killer T cell lymphoma (NKTL)

Natural killer T cell lymphoma (NKTL) is an aggressive disease with very poor treatment outcomes in the advanced stages. With chemotherapy, initial response rates to treatment are high but responses are short lived. A better understanding of the complex molecular pathogenesis of this disease is essential in order to design and develop better therapeutics with improved efficacy. This review aims to summarise the key pathogenic mechanisms in NKTL which may have significant prognostic and therapeutic implications.

Opportunities to Target the Life Cycle of Epstein-Barr Virus (EBV) in EBV-Associated Lymphoproliferative Disorders

Many lymphoproliferative disorders (LPDs) are considered “EBV associated” based on detection of the virus in tumor tissue. EBV drives proliferation of LPDs via expression of the viral latent genes and many pre-clinical and clinical studies have shown EBV-associated LPDs can be treated by exploiting the viral life cycle. After a brief review of EBV virology and the natural life cycle within a host we will discuss the importance of the viral gene programs expressed during specific viral phases, as well as within immunocompetent vs. immunocompromised hosts and corresponding EBV-associated LPDs. We will then review established and emerging treatment approaches for EBV-associated LPDs based on EBV gene expression programs. Patients with EBV-associated LPDs can have a poor performance status, multiple comorbidities, and/or are immunocompromised from organ transplantation, autoimmune disease, or other congenital or acquired immunodeficiency making them poor candidates to receive intensive cytotoxic chemotherapy. With the emergence of EBV-directed therapy there is hope that we can devise more effective therapies that confer milder toxicity.

Revisiting the Tissue Microenvironment of Infectious Mononucleosis: Identification of EBV Infection in T Cells and Deep Characterization of Immune Profiles

To aid understanding of primary EBV infection, we have performed an in depth analysis of EBV-infected cells and of local immune cells in tonsils from infectious mononucleosis (IM) patients. We show that EBV is present in approximately 50% of B-cells showing heterogeneous patterns of latent viral gene expression probably reflecting different stages of infection. While the vast majority of EBV+ cells are B-cells, around 9% express T-cell antigens, with a predominance of CD8+ over CD4+ cells. PD-L1 was expressed by a median of 14% of EBV+ cells. The numbers of EBER+PD-L1+ cells were directly correlated with the numbers of EBER+CD3+ and EBER+CD8+ cells suggesting a possible role for PD-L1 in EBV infection of T-cells. The microenvironment of IM tonsils was characterized by a predominance of M1-polarized macrophages over M2-polarized cells. However, at the T-cell level, a heterogeneous picture emerged with numerous Th1/cytotoxic cells accompanied and sometimes outnumbered by Th2/regulatory T-cells. Further, we observed a direct correlation between the numbers of Th2-like cells and EBV- B-cells. Also, a prevalence of cytotoxic T-cells over Th2-like cells was associated with an increased viral load. These observations point to contribution of B- and Th2-like cells to the control of primary EBV infection. 35% of CD8+ cells were differentiated CD8+TBET+ cells, frequently detected in post-capillary venules. An inverse correlation was observed between the numbers of CD8+TBET+ cells and viral load suggesting a pivotal role for these cells in the control of primary EBV infection. Our results provide the basis for a better understanding of immune reactions in EBV-associated tumors.

Peripheral T-Cell Lymphoma, not Otherwise Specified (PTCL-NOS)

Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) is a World Health Organization (WHO)-defined diagnostic category within the highly heterogeneous group of mature post-thymic T-cell neoplasms. It is the most common subtype of mature post-thymic T-cell neoplasms globally, accounting for up to 35% of PTCL cases in Europe and North America. PTCL-NOS is a diagnosis of exclusion, comprising several disease entities that differ in biology, clinical presentation, and outcome. The diagnosis of PTCL-NOS is made based on the presence of typical histopathological features of lymphoma, an aberrant T-cell immunophenotype, often with a loss of CD5 and CD7, and a clonal T-cell receptor (TCR) gene rearrangement, in the appropriate clinical context. Unlike other types of T-cell lymphoma, recurrent mutations to assist with the diagnosis have not been identified. Patients often present with advanced stage. Prognosis is poor, with a 5-year overall survival (OS) of 20-30%. Anthracycline-based combination chemotherapy remains the most frequently used frontline strategy, with overall response rates (ORR) of 50-60%, and complete response rates (CRR) of 20-30%. Prospective studies with intent-to-treat analyses have shown that consolidation with high-dose chemotherapy and autologous stem cell transplant (ASCT) results in progression-free survivals (PFS) that compare favorably with historical cohorts and may improve OS in selected patient populations. However, randomized data are still lacking. Over the past decade, therapeutic agents approved in the relapsed and refractory setting have produced response rates of up to 33% and median PFS up to 18 months. Overall, outcomes remain poor and there is a dire need for more effective treatments. This review discusses the latest information on the diagnosis and treatment of PTCL-NOS.

The Clinical Utility of Circulating Epstein-Barr Virus DNA Concentrations in NK/T-Cell Lymphoma: A Meta-Analysis

Background

Circulating Epstein-Barr virus (EBV) DNA concentrations were reported to have prognostic value for NK/T-cell lymphoma patients in limited small-scale studies. In this study, we aimed to evaluate the clinical utility of circulating EBV-DNA concentrations to a large sample of NK/T-cell lymphoma patients.

Methods

We conducted this meta-analysis, which included a total of 15 prospective and retrospective comparable studies to assess the association between pretreatment EBV-DNA (pre-DNA), posttreatment EBV-DNA (post-DNA), and clinical outcomes of NK/T-cell lymphoma patients. We chose overall survival (OS) as the primary endpoint and progression-free survival (PFS), complete response (CR), and overall response rate (ORR) as secondary endpoints.

Results

High pre-DNA and detectable post-DNA were both significantly correlated with poorer OS in NK/T-cell lymphoma patients (P < 0.05), with hazard radios (HRs) equal to 3.45 and 2.30, respectively. High pre-DNA and detectable post-DNA also predicted poorer PFS. Additionally, high pre-DNA was found to be significantly correlated with both worse CR and ORR, which indicated worse treatment response.

Conclusion

Circulating EBV-DNA concentrations provides prognostic values of survival and treatment response in NK/T-cell lymphoma patients.

Epstein-Barr Virus Type 2 Infects T Cells and Induces B Cell Lymphomagenesis in Humanized Mice

Epstein-Barr virus (EBV) has been classified into two strains, EBV type 1 (EBV-1) and EBV type 2 (EBV-2) based on genetic variances and differences in transforming capacity. EBV-1 readily transforms B cells in culture while EBV-2 is poorly transforming. The differing abilities to immortalize B cells in vitro suggest that in vivo these viruses likely use alternative approaches to establish latency. Indeed, we recently reported that EBV-2 has a unique cell tropism for T cells, infecting T cells in culture and in healthy Kenyan infants, strongly suggesting that EBV-2 infection of T cells is a natural part of the EBV-2 life cycle. However, limitations of human studies hamper further investigation into how EBV-2 utilizes T cells. Therefore, BALB/c Rag2^null IL2rγ^null SIRPα humanized mice were utilized to develop an EBV-2 in vivo model. Infection of humanized mice with EBV-2 led to infection of both T and B cells, unlike infection with EBV-1, in which only B cells were infected. Gene expression analysis demonstrated that EBV-2 established a latency III infection with evidence of ongoing viral reactivation in both B and T cells. Importantly, EBV-2-infected mice developed tumors resembling diffuse large B cell lymphoma (DLBCL). These lymphomas had morphological features comparable to those of EBV-1-induced DLBCLs, developed at similar rates with equivalent frequencies, and expressed a latency III gene profile. Thus, despite the impaired ability of EBV-2 to immortalize B cells in vitro, EBV-2 efficiently induces lymphomagenesis in humanized mice. Further research utilizing this model will enhance our understanding of EBV-2 biology, the consequence of EBV infection of T cells, and the capacity of EBV-2 to drive lymphomagenesis.IMPORTANCE EBV is a well-established B cell-tropic virus. However, we have recently shown that the EBV type 2 (EBV-2) strain also infects primary T cells in culture and in healthy Kenyan children. This finding suggests that EBV-2, unlike the well-studied EBV-1 strain, utilizes the T cell compartment to persist. As EBV is human specific, studies to understand the role of T cells in EBV-2 persistence require an in vivo model. Thus, we developed an EBV-2 humanized mouse model, utilizing immunodeficient mice engrafted with human cord blood CD34⁺ stem cells. Characterization of the EBV-2-infected humanized mice established that both T cells and B cells are infected by EBV-2 and that the majority of infected mice develop a B cell lymphoma resembling diffuse large B cell lymphoma. This new in vivo model can be utilized for studies to enhance our understanding of how EBV-2 infection of T cells contributes to persistence and lymphomagenesis.

COMPARATIVE ANALYSIS OF SEROLOGICAL MARKERS OF HERPES VIRUSES AND QUANTITATIVE IMMUNOGLOBULINOPATHIES IN PRIMARY PATIENTS WITH ANGIOIMMUNOBLASTIC T-CELL LYMPHOMA

INTRODUCTION

Angioimmunoblastic T-cell lymphoma (AITL) is associated with the Epstein-Barr virus (EBV) in most cases. It is believed polyclonal hypergammaglobulinaemia observed in 53-80% of AITL patients has anti-herpes viral antibodies as its substrate.

AIM

The aim of the study was to compare serological markers of herpes viruses and quantitative immunoglobulinopathies of classes M and G in primary patients with AITL.

MATERIALS AND METHODS

26 primary patients with newly diagnosed AITL treated at the National Research Center for Hematology from 2002 to 2017 were enrolled in the study. The male/female ratio was 16/10; median age was 62 (29-81) years. The levels of total immunoglobulins of classes M and G, serological markers of EBV, cytomegalovirus (CMV) and herpes simplex virus type 1 and type 2 (HSV 1, 2) were assessed in all patients.

RESULTS

Significant relationship was found between the presence of virus-specific IgM (IgM HSV 1, 2, IgM CMV, IgM VCA EBV) and an elevated level of total immunoglobulins of class M (p.

Epstein-Barr virus (EBV)-associated lymphoid proliferations, a 2018 update

Epstein-Barr virus (EBV) has been linked to many human neoplasms including hematopoietic, epithelial, and mesenchymal tumors. Since our original review of EBV-associated lymphoproliferative disorders in 2007, many advances and developments have been reported. In this review, we will examine the recent advances in EBV-associated lymphoid/histiocytic proliferations, dividing them into reactive, B cell, T/NK cell, immunodeficiency-related, and histiocytic/dendritic cell proliferations.

EBV in T-/NK-Cell Tumorigenesis

Epstein-Barr virus (EBV), which is associated with B-cell proliferative disorders, also transforms T- or natural killer (NK)-lineage cells and has been connected with various T- or NK (T/NK)-cell malignancies, such as extranodal NK/T-cell lymphoma-nasal type and aggressive NK-cell leukemia. Chronic active EBV (CAEBV) disease , which occurs most often in children and young adults in East Asia, is an EBV-associated T-/NK-cell lymphoproliferative disease. Patients with CAEBV often progress to overt lymphoma or leukemia over a long-term clinical course. EBV's transforming capacity in B cells is well characterized, but the molecular pathogenesis of clonal expansion caused by EBV in T/NK cells has not yet been clarified. In the primary infection, EBV infects B cells and epithelial cells and may also infect some T/NK cells. In some individuals, because of poor presentation by specific human leukocyte antigens or the genetic background, EBV-infected T/NK cells evade host immunity and survive. Occasionally, with the help of viral oncogenes, EBV-associated T/NK lymphoproliferative diseases, such as CAEBV, may develop. The subsequent accumulation of genetic mutations and/or epigenetic modifications in driver genes, such as DDX3X and TP53, may lead to overt lymphoma and leukemia. Activation-induced cytidine deaminase and the APOBEC3 family, driven by EBV infection, may induce chromosomal recombination and somatic mutations.

Central nervous system leukemia in a patient with concurrent nasopharyngeal carcinoma and acute myeloid leukaemia: A case report

RATIONALE

Concurrent case of nasopharyngeal carcinoma (NPC) and acute myeloid leukemia (AML) has not been reported. Here, we report a case of NPC, who was concurrently suffered from AML one mother after the NPC diagnosis.

PATIENT CONCERNS

The patient was a 45-year-old male who presented with a mass on his right side neck.

DIAGNOSES

The patient was diagnosed with Epstein-Barr virus negative type-2 non-keratinizing carcinoma with clivus involvement and unilateral metastasis to the cervical lymph node.

INTERVENTIONS

He was treated with one cycle of cisplatin and 69.76 Gy of concurrent external-beam radiation.

OUTCOMES

Three months after completion of chemo-radiotherapy, the patient was diagnosed as acute myeloid leukemia, which achieved complete remission after one course induction chemotherapy. Two months later, however, the patient was diagnosed as central nervous system leukemia. He ultimately died of relapsed leukemia. The overall survival of the patient was 10 months.

LESSONS

The co-occurrence of NPC and AML is rare and prognosis is poor. Radiotherapy in NPC can disrupt the blood-brain barrier, which may contribute to the pathogenesis of central nervous system leukemia. Early alert and prevention of central nervous system leukemia following radiotherapy in NPC patient is recommended.

Epstein-Barr Virus Type 2 Infects T Cells in Healthy Kenyan Children

Background

The 2 strains of Epstein-Barr virus (EBV), EBV type 1 (EBV-1) and EBV-2, differ in latency genes, suggesting that they use distinct mechanisms to establish latency. We previously reported that EBV-2 infects T cells in vitro. In this study, we tested the possibility that EBV-2 infects T cells in vivo.

Methods

Purified T-cell fractions isolated from children positive for EBV-1 or EBV-2 and their mothers were examined for the presence of EBV and for EBV type.

Results

We detected EBV-2 in all T-cell samples obtained from EBV-2-infected children at 12 months of age, with some children retaining EBV-2-positive T cells through 24 months of age, suggesting that EBV-2 persists in T cells. We were unable to detect EBV-2 in T-cell samples from mothers but could detect EBV-2 in samples of their breast milk and saliva.

Conclusions

These data suggest that EBV-2 uses T cells as an additional latency reservoir but that, over time, the frequency of infected T cells may drop below detectable levels. Alternatively, EBV-2 may establish a prolonged transient infection in the T-cell compartment. Collectively, these novel findings demonstrate that EBV-2 infects T cells in vivo and suggest EBV-2 may use the T-cell compartment to establish latency.

Association between extranodal natural killer/T-cell lymphoma and hepatitis B viral infection: a case-control study

Extranodal natural killer/T-cell lymphoma, nasal type (ENKTL) is a rare subtype of lymphoma that is often associated with poor clinical prognosis. Several studies have shown that hepatitis B virus (HBV) infection may be associated with increased risk of B-cell non-Hodgkin lymphoma; however, because of the rarity of ENKTL, little is known about its association with HBV. Our study aimed to assess whether HBV infection was associated with increased odds of ENKTL. We conducted a hospital-based case-control study including 417 ENKTL cases and 488 age- and sex-matched subjects with nonmalignant diseases unrelated to HBV infection. Multivariable unconditional logistic regression analyses were performed to estimate adjusted odds ratios [AOR] and their corresponding 95% confidence intervals (CI). The results of the multivariable analysis showed that after adjustment for a set of known risk factors, patients previously infected with HBV (HBsAg-seronegative/anti-HBc-seropositive) and naturally immune to HBV (anti-HBs-seropositive/anti-HBc-seropositive) were at significantly greater odds of being diagnosed with ENKTL (AOR, 1.497; 95% CI 1.098-2.042, P=0.033 and AOR, 1.871; 95% CI 1.302-2.689, P=0.001, respectively). After adjusting for other factors, significantly greater odds of being diagnosed with ENKTL were observed among cases who reported ever drinking alcohol (AOR, 1.675; 95% CI 1.054-2.660, P=0.029). The odds of ENKTL diagnosis were not significantly associated with ABO blood type, cigarette smoking status or family history of cancer. The results of our study suggest that patients previously infected with HBV and naturally immune to HBV were at greater odds of being diagnosed with ENKTL.

The Molecular Pathology of Lung Cancer

Advances in lung cancer genomics have revolutionized the diagnosis and treatment of this heterogeneous and clinically significant group of tumors. This article provides a broad overview of the most clinically relevant oncogenic alterations in common and rare lung tumors, with an emphasis on the pathologic correlates of the major oncogenic drivers, including EGFR, KRAS, ALK, and MET. Illustrations emphasize the morphologic diversity of lung adenocarcinoma, including genotype-phenotype correlations of genomic evolution in tumorigenesis. Molecular diagnostic approaches, including PCR-based testing, massively parallel sequencing, fluorescence in situ hybridization, and immunohistochemistry are reviewed.

A Rare Case of Angioimmunoblastic T-Cell Lymphoma with Epstein-Barr Virus-Negative Reed-Sternberg-Like B-Cells, Chylous Ascites, and Chylothorax

Angioimmunoblastic T-cell lymphoma is a rare non-Hodgkin lymphoma with dismal prognosis. The median age of presentation ranges from 62 to 69 years with generalized lymphadenopathy, B symptoms, and hepatosplenomegaly as the most prevalent symptoms. The combination of B-cell and T-cell proliferations is common in AITL and the B-cell component may resemble Reed-Sternberg-like B-cells. Epstein-Barr virus is estimated to be present in 80–95% of AITL biopsies. Only a handful of EBV-negative AITL cases with EBV-negative RS-like B-cells have been reported over the last decade. We present a rare case of EBV-negative AITL with chylous ascites and chylothorax. Microscopic and immunohistochemical analysis revealed the presence of EBV-negative Reed-Sternberg-like B-cells in the tumor.

Frequency and clinical correlates of elevated plasma Epstein-Barr virus DNA at diagnosis in peripheral T-cell lymphomas

Epstein-Barr virus (EBV)-encoded RNAs (EBER) in tumor tissue and cell-free plasma EBV-DNA (pEBVd) are detected in EBV-associated lymphomas. Studies have suggested that EBER+ peripheral T-cell lymphomas (PTCL) have worse prognosis but the role of EBV in these neoplasms remains unclear. pEBVd is quantitative and more easily amenable to standardization than EBER, but frequency of pEBVd detection, clinical impact and agreement with EBER status in PTCL are unknown. We retrospectively assessed frequency of detectable pre-treatment pEBVd, presence of EBER in tumor tissue, and outcomes in 61 of 135 EBV-assessable PTCL patients. Fifteen of 61 patients (24.5%, 95% CI: 14-37%) were pre-treatment pEBVd+, with no significant differences in baseline characteristics or treatment between pEBVd+ and pEBVd- patients. EBER-ISH was performed on 10 pEBVd+ and 35 pEBVd- tumors. All 10 pEBVd+ patients were EBER+, but 9 pEBVd- patients were also EBER+. With median follow up of 24 months (range 1-96), overall survival (OS) was shorter in pEBVd+ compared to pEBVd- patients (13 vs. 72 months; p = 0.04). In our retrospective study, pre-treatment pEBVd was elevated in 25% of PTCL patients, was highly specific for EBER+ tumors, and was associated with shorter survival. pEBVd should be further explored as a prognostic variable and tumor biomarker in PTCL.

Toward a Biology-Driven Treatment Strategy for Peripheral T-cell Lymphoma

T-cell and natural killer–cell lymphomas are a relatively rare and heterogeneous group of diseases that are difficult to treat and usually have poor outcomes. To date, therapeutic interventions are of limited efficacy and there is a pressing need to find better treatments. In recent years, advances in molecular biology have helped to elucidate the underlying genetic complexity of this group of diseases and to identify mutations and signaling pathways involved in lymphomagenesis. In this review, we highlight the unique biological characteristics of some of the different subtypes and discuss how these may be targeted to provide more individualized and effective treatment approaches.

T-cell lymphomas, a challenging disease: types, treatments, and future

T-cell lymphomas are rare and aggressive malignancies associated with poor outcome, often because of the development of resistance in the lymphoma against chemotherapy as well as intolerance in patients to the established and toxic chemotherapy regimens. In this review article, we discuss the epidemiology, pathophysiology, current standard of care, and future treatments of common types of T-cell lymphomas, including adult T-cell leukemia/lymphoma, angioimmunoblastic T-cell lymphoma, anaplastic large-cell lymphoma, aggressive NK/T-cell lymphoma, and cutaneous T-cell lymphoma.

PD-L1 is upregulated by EBV-driven LMP1 through NF-κB pathway and correlates with poor prognosis in natural killer/T-cell lymphoma

BACKGROUND

Natural killer/T-cell lymphoma (NKTCL) is an Epstein-Barr virus (EBV)-associated, highly aggressive lymphoma. Treatment outcome remains sub-optimal, especially for advanced-stage or relapsed diseases. Programmed cell death receptor 1 (PD-1) and PD ligand 1 (PD-L1) have become promising therapeutic targets for various malignancies, but their role in the pathogenesis and their interactions with EBV in NKTCL remains to be investigated.

METHODS

Expression of PD-L1 was measured in NK-92 (EBV-negative) and SNK-6 (EBV-positive) cells by western blot, quantitative real-time PCR and enzyme-linked immunosorbent assay, and flow cytometry, respectively. Latent membrane protein 1 (LMP1)-harboring lentiviral vectors were transfected into NK-92 cells to examine the correlation between LMP1 and PD-L1 expression. Proteins in the downstream pathways of LMP1 signaling were measured in NK-92 cells transfected with LMP1-harboring or negative control vectors as well as in SNK-6 cells. PD-L1 expression on tumor specimens and serum concentration of soluble PD-L1 were collected in a retrospective cohort of patients with Ann Arbor stage I~II NKTCL, and their prognostic significance were analyzed.

RESULTS

Expression of PD-L1 was significantly higher in SNK-6 cells than in NK-92 cells, at both protein and mRNA levels. Expression of PD-L1 was remarkably upregulated in NK-92 cells transfected with LMP1-harboring lentiviral vectors compared with those transfected with negative control vectors. Proteins in the MAPK/NF-κB pathway were upregulated in LMP1-expressing NK-92 cells compared with the negative control. Selective inhibitors of those proteins induced significant downregulation of PD-L1 expression in LMP1-expressing NK-92 cells as well as in SNK-6 cells. Patients with a high concentration of serum soluble PD-L1 (≥3.4 ng/ml) or with a high percentage of PD-L1 expression in tumor specimens (≥38 %) exhibited significantly lower response rate to treatment and remarkably worse survival, compared with their counterparts. A high concentration of serum soluble PD-L1 and a high percentage of PD-L1 expression in tumor specimens were independent adverse prognostic factors among patients with stage I~II NKTCL.

CONCLUSIONS

PD-L1 expression positively correlated LMP1 expression in NKTCL, which was probably mediated by the MAPK/NF-κB pathway. PD-L1 expression in serum and tumor tissues has significant prognostic value for early-stage NKTCL.

Clinical features and treatment outcome of Epstein-Barr virus-positive nodal T-cell lymphoma

The classification of mature NK-/T-cell lymphoma mainly originating from the T-cell lineage with predominantly nodal involvement and Epstein-Barr virus (EBV) positivity in a majority of tumor cells is unresolved. We analyzed the clinical features and treatment outcomes of such patients. Five patients with EBV-positive nodal T-cell lymphoma were surveyed during follow-up period. The median age was 53 years (range 33-88 years), and all patients showed nodal involvement. The patients mostly presented advanced clinical features, such as stage III or IV disease, elevated lactate dehydrogenase, and hemophagocytosis. Four patients received cyclophosphamide-containing chemotherapy at the time of diagnosis. However, three patients (75 %) showed disease progression during the early cycles of initial treatment. The median overall survival was 1.5 months (95 % CI 0.0-3.4 months). Patients with EBV-positive nodal T-cell lymphoma mainly show lymph node involvement, but also show aggressive clinical features and poor treatment outcomes, such as aggressive NK-cell leukemia. Therefore, we should consider EBV-positive nodal T-cell lymphoma to be a unique disease entity distinct from peripheral T-cell lymphoma not otherwise specified.

[NK/T-cell Lymphoma of nasal-type: A rare affection with a poor prognosis]

INTRODUCTION

NK/T cell lymphoma of nasal-type was described in 1933 as a malignant midfacial granuloma. The diagnosis of this rare affection is clinical and immunohistopathological. We report a case of NK/T cell lymphoma diagnosed at an advanced stage.

OBSERVATION

A 60-year-old man with no particular medical history presented since seven months with a left nasal obstruction associated with a purulent and fetid rhinorrhea followed by a centrifugal midfacial necrosis. Blood tests showed an inflammatory syndrome. The CT-scan of the face showed a filling of the nose and sinus by a tissular process and a lysis of the bone walls. Three series of biopsies (le last being performed under general anesthesia) were necessary to get the diagnosis of NK/T cell lymphoma. The standard histology showed a malignant proliferation made of round and spindle-shaped lymphoid-like cells and angiocentric arrangement. The cells were CD 2+, CD 3+, CD 5+ and CD 56+. The spontaneous evolution was fatal one month after diagnosis in a context of septic shock.

CONCLUSION

NK/T cell lymphoma of nasal-type is a rare disease but should be evocated in patient with midfacial necrosis of centrifugal evolution. The diagnosis certainty is made on immunohistopathological analysis. Multiple biopsies, made at distance from necrotic areas and under general anesthesia may be necessary.