Epstein-Barr virus-positive diffuse large B-cell lymphoma

EBV and Lymphomagenesis

The clinical significance of Epstein–Barr virus (EBV) cannot be understated. Not only does it infect approximately 90% of the world’s population, but it is also associated with numerous pathologies. Diseases linked to this virus include hematologic malignancies such as diffuse large B-cell lymphoma, Hodgkin lymphoma, Burkitt lymphoma, primary CNS lymphoma, and NK/T-cell lymphoma, epithelial malignancies such as nasopharyngeal carcinoma and gastric cancer, autoimmune diseases such as multiple sclerosis, Graves’ disease, and lupus. While treatment for these disease states is ever evolving, much work remains to more fully elucidate the relationship between EBV, its associated disease states, and their treatments. This paper begins with an overview of EBV latency and latency-associated proteins. It will then review EBV’s contributions to select hematologic malignancies with a focus on the contribution of latent proteins as well as their associated management.

Viral Agents as Potential Drivers of Diffuse Large B-Cell Lymphoma Tumorigenesis

Among numerous causative agents recognized as oncogenic drivers, 13% of total cancer cases occur as a result of viral infections. The intricacy and diversity of carcinogenic processes, however, raise significant concerns about the mechanistic function of viruses in cancer. All tumor-associated viruses have been shown to encode viral oncogenes with a potential for cell transformation and the development of malignancies, including diffuse large B-cell lymphoma (DLBCL). Given the difficulties in identifying single mechanistic explanations, it is necessary to combine ideas from systems biology and viral evolution to comprehend the processes driving viral cancer. The potential for more efficient and acceptable therapies lies in targeted medicines that aim at viral proteins or trigger immune responses to either avoid infection or eliminate infected or cancerous cells. In this review, we aim to describe the role of viral infections and their mechanistic approaches in DLBCL tumorigenesis. To the best of our knowledge, this is the first review summarizing the oncogenic potential of numerous viral agents in DLBCL development.

Virus-Mediated Inhibition of Apoptosis in the Context of EBV-Associated Diseases: Molecular Mechanisms and Therapeutic Perspectives

Epstein-Barr virus (EBV), the representative of the Herpesviridae family, is a pathogen extensively distributed in the human population. One of its most characteristic features is the capability to establish latent infection in the host. The infected cells serve as a sanctuary for the dormant virus, and therefore their desensitization to apoptotic stimuli is part of the viral strategy for long-term survival. For this reason, EBV encodes a set of anti-apoptotic products. They may increase the viability of infected cells and enhance their resistance to chemotherapy, thereby contributing to the development of EBV-associated diseases, including Burkitt’s lymphoma (BL), Hodgkin’s lymphoma (HL), gastric cancer (GC), nasopharyngeal carcinoma (NPC) and several other malignancies. In this paper, we have described the molecular mechanism of anti-apoptotic actions of a set of EBV proteins. Moreover, we have reviewed the pro-survival role of non-coding viral transcripts: EBV-encoded small RNAs (EBERs) and microRNAs (miRNAs), in EBV-carrying malignant cells. The influence of EBV on the expression, activity and/or intracellular distribution of B-cell lymphoma 2 (Bcl-2) protein family members, has been presented. Finally, we have also discussed therapeutic perspectives of targeting viral anti-apoptotic products or their molecular partners.

The Emerging Treatment Options of Plasmablastic Lymphoma: Analysis of 173 Individual Patient Outcomes

Plasmablastic lymphoma (PBL) is a newly recognized aggressive subtype of non-Hodgkin lymphoma. Its rarity hinders testing effective treatment options in clinical trials. We conducted a systematic review of PubMed and our internal records to retrieve patients with a PBL diagnosis with evaluable treatment outcomes. Aggressive chemotherapy was defined as more intense regimens than CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone). We compiled a meta-dataset of 173 patients. The median age at diagnosis was 48.5 years, 75% of patients were male, and stages III/IV accounted for 47% of the cohort. Of 138 patients with known response status after first-line chemotherapy, 63 (45%) achieved a complete response with a 2-year relapse-free survival of 71.6%. Sixty-nine (50%) patients received first-line CHOP. There was no significant difference in the objective response rate among the 2 most commonly used regimens, CHOP and DA-EPOCH (dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin) (69% vs. 79%; P = .4). The median follow-up was 9 months, and the 2-year overall survival (OS) was 47.4%. A univariate analysis identified factors associated with worse OS, including stage III/IV (hazard ratio [HR], 2.82; P < .001), human herpes virus-8-positive (HR, 3.30; P = .01), bone marrow (HR, 1.07; P = .035), and cardiorespiratory involvement (HR, 2.26; P = .015). Meanwhile, Epstein-Varr virus-encoded small RNA-positivity (HR, 0.31; P < .001) and involvement of head and neck (HR, 0.44; P = .009) were associated with better OS. Multivariate analysis showed that aggressive chemotherapy was significantly associated with better OS (HR, 0.22; P = .016). Patients with PBL with high-risk features, such as advanced stage, human herpes virus-8-positivity, bone marrow, and cardiorespiratory involvement, require more aggressive chemotherapy. Bortezomib and lenalidomide are promising add-on agents.

A Rare, Yet Treatable Pancreatic Tumor: Epstein-Barr Virus-Positive Diffuse Large B-Cell Lymphoma

BACKGROUND Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL) is a rare subtype of B-cell neoplasm that can have diverse presentations. When it involves the pancreas (i.e., pancreatic lymphoma), it can mimic metastatic pancreatic adenocarcinoma. Pancreatic lymphoma and adenocarcinoma often have similar clinical, laboratory, and radiographic features making the distinction challenging without pathological tissue examination. The differentiation of these 2 entities is important as the prognosis of pancreatic lymphoma is certainly more favorable with a chance of cure with chemoimmunotherapy. CASE REPORT We present an unusual case of EBV-positive DLBCL involving the pancreas that was initially believed to be metastatic pancreatic adenocarcinoma. The patient was treated with chemoimmunotherapy and had a remarkable response. This is the first known case of EBV-positive DLBCL involving the pancreas that was successfully treated with chemoimmunotherapy. CONCLUSIONS EBV-positive DLBCL can have diverse presentations, including a pancreatic mass with multi-organ involvement, which mimics metastatic pancreatic adenocarcinoma. The prognosis of EBV-positive DLBCL is thought to be worse than that of EBV-negative tumors. However, it remains certainly superior to that of its adenocarcinoma counterpart with conventional chemoimmunotherapy.

Diffuse Large B-Cell Lymphoma in Kenya: MYC, BCL2, and the Cell of Origin

PURPOSE

Diffuse large B-cell lymphoma (DLBCL) is the most commonly diagnosed non-Hodgkin lymphoma in adults in Kenya. Cell of origin (COO) and double expression of MYC and BCL2 are two important prognostic factors for DLBCL. A small subset (5% to 10%) of DLBCL cases show positivity for CD5 and are associated with poor prognosis, whereas CD30 antigen, seen in up to 10% of cases, may be a useful target for therapy. We sought to determine the prevalence of MYC/BCL2 double expression, COO, and proportion of Epstein-Barr virus positivity among patients with DLBCL diagnosed at a tertiary referral laboratory in Kenya.

PATIENTS AND METHODS

All cases of DLBCL diagnosed from 2012 through 2015 in our pathology department were analyzed. Tumor tissue microarray sections were stained with CD20, CD3, CD5, CD30, BCL2, BCL6, CD10, MUM1, MYC, and Ki67, classified for COO on the basis of the Hans algorithm, and subjected to Epstein-Barr virus-encoded small RNAs in situ hybridization.

RESULTS

Among 165 DLBCL cases, the median age was 50 years, and there was no sex predilection. Only 18 (10.9%) cases showed double expression for MYC and BCL2. Germinal center B (GCB)-cell type DLBCL accounted for 67 cases (40.6%) and 97 cases (59.4%) were classified as non-GCB. The mean Ki67 proliferation index was significantly higher in the double-expressing (45%) and non-GCB groups (36%) compared with the non-double-expressing group (29%) and GCB group (26%). Sixteen cases (9.7%) were Epstein-Barr virus-encoded small RNAs positive, 12 (75%) of which were non-GCB.

CONCLUSION

DLBCL in Kenya is seen in much younger patients with the poor prognostic non-GCB-type accounting for 59.4% of cases. MYC and BCL2 double expression was seen in fewer tumors than reported in the literature and in significantly older patients.

Tissue Necrosis in Epstein-Barr Virus-Negative Orbital Diffuse Large B-Cell Lymphoma

An 82-year-old man presented with a history of diplopia for 5 months and painful swelling of the left eyelids for 3 months. Imaging studies revealed a lesion involving the left extraocular muscles, orbital fat, and optic nerve. Laboratory investigations were negative for Epstein-Barr virus antiviral capsid antigens-immunoglobulin M. Initial biopsy of the lesion was performed and histopathologic examination revealed only necrosis with positivity of cluster of differentiation 20. This prompted a second biopsy of the involved left extraocular muscles and the orbital fat. The results of histopathological and immunohistochemical tests corresponded to Epstein-Barr virus-negative diffuse large B-cell lymphoma, germinal center B-cell type.

Identification of B-cell translocation gene 1-controlled gene networks in diffuse large B-cell lymphoma: A study based on bioinformatics analysis

B-cell translocation gene 1 (BTG1) is a member of the BTG/transducer of Erb family. The present study evaluated the impact of BTG1 gene expression on the clinical outcome of diffuse large B-cell lymphoma (DLBCL) and investigated potential mechanisms using the Gene Expression Omnibus (GEO) database. The gene expression profile datasets GSE31312, GSE10846, GSE65420 and GSE87371 were downloaded from the GEO database. BTG1 expression and clinicopathological data were obtained from the GSE31312 dataset. In 498 cases, the expression of BTG1 in DLBCL was associated with treatment response (χ²=19.020; P<0.001) and International Prognostic Index score (χ²=5.320; P=0.025). Using the Kaplan-Meier method, it was identified that the expression of BTG1 was associated with overall survival (OS) and progression-free survival (PFS) times. Univariate and multivariate Cox regression analysis demonstrated that BTG1 was an independent predictive factor for OS and PFS. From the overlapping analysis of 407 BTG1-associated genes and 22,187 DLBCL-associated genes, 401 genes were identified as BTG1-associated DLBCL genes. Pathway analysis revealed that BTG1-associated DLBCL genes were associated with cancer progression and DLBCL signaling pathways. Subsequently, a protein-protein interaction network was constructed of the BTG1-associated genes, which consisted of 235 genes and 601 interactions. Additionally, 24 genes with high degrees in the network were identified as hub genes, which included genes associated with ‘ribosome’ [ribosomal protein (RP) L11, RPL3, RPS29, RPL19, RPL15 and RPL12], ‘cell cycle’ (ubiquitin carboxyl extension protein 52, ATM and Ras homolog family member H), ‘mitogen-activated protein kinase pathway’ (mitogen-activated protein kinase 1), ‘histone modification’ (ASH1-like protein) and ‘transcription/translation’ (eukaryotic translation initiation factor 3 subunit E, eukaryotic translation elongation factor 1 δ, transcription termination factor 1, cAMP responsive element binding protein 1 and RNA polymerase II subunit F). In conclusion, BTG1 may serve as a predictive biomarker for DLBCL prognosis. Additionally, bioinformatics analysis indicated that BTG1 may exhibit key functions in the progression and development of DLBCL.

Oral Manifestation of Lymphomatoid Granulomatosis

Lymphomatoid granulomatosis (LYG) is a rare B-cell lymphoproliferative disorder driven by Esptein-Barr virus (EBV) that most commonly affects the lungs, although extra pulmonary sites like the central nervous system, skin, liver and kidney can also be involved. It is microscopically characterized by an angiocentric and angiodestructive growth pattern, predominantly composed by small T-cells, although a smaller population of atypical large B-cells is considered the true neoplastic component. Oral cavity involvement of LYG has rarely been described and the diagnosis of this neoplasm is very difficult. The aim of this report is to present a rare case of LYG affecting an 86-year-old female patient that was diagnosed due to an extensive, ulcerated and painful oral lesion affecting the hard palate. Detailed microscopic evaluation together with a large immunohistochemical study were necessary to achieve the correct diagnosis of LYG.