Helicobacter pylori and Epstein-Barr virus infection in cell polarity alterations.

The asymmetrical distribution of the cellular organelles inside the cell is maintained by a group of cell polarity proteins. The maintenance of polarity is one of the vital host defense mechanisms against pathogens, and the loss of it contributes to infection facilitation and cancer progression. Studies have suggested that infection of viruses and bacteria alters cell polarity. Helicobacter pylori and Epstein-Barr virus are group I carcinogens involved in the progression of multiple clinical conditions besides gastric cancer (GC) and Burkitt's lymphoma, respectively. Moreover, the coinfection of both these pathogens contributes to a highly aggressive form of GC. H. pylori and EBV target the host cell polarity complexes for their pathogenesis. H. pylori-associated proteins like CagA, VacA OipA, and urease were shown to imbalance the cellular homeostasis by altering the cell polarity. Similarly, EBV-associated genes LMP1, LMP2A, LMP2B, EBNA3C, and EBNA1 also contribute to altered cell asymmetry. This review summarized all the possible mechanisms involved in cell polarity deformation in H. pylori and EBV-infected epithelial cells. We have also discussed deregulated molecular pathways like NF-κB, TGF-ß/SMAD, and ß-catenin in H. pylori, EBV, and their coinfection that further modulate PAR, SCRIB, or CRB polarity complexes in epithelial cells.

Helicobacter pylori and Epstein-Barr Virus Coinfection Stimulates Aggressiveness in Gastric Cancer through the Regulation of Gankyrin.

Persistent coinfection with Helicobacter pylori and Epstein-Barr virus (EBV) promotes aggressive gastric carcinoma (GC). The molecular mechanisms underlying the aggressiveness in H. pylori and EBV-mediated GC are not well characterized. We investigated the molecular mechanism involved in H. pylori- and EBV-driven proliferation of gastric epithelial cells. Results showed that the coinfection is significantly more advantageous to the pathogens as coinfection creates a microenvironment favorable to higher pathogen-associated gene expression. The EBV latent genes ebna1 and ebna3c are highly expressed in the coinfection compared to lone EBV infection at 12 and 24 h. The H. pylori-associated genes 16S rRNA, cagA, and babA were also highly expressed during coinfection compared to H. pylori alone. In addition, upregulation of gankyrin, which is a small oncoprotein, modulates various cell signaling pathways, leading to oncogenesis. Notably, the knockdown of gankyrin decreased the cancer properties of gastric epithelial cells. Gankyrin showed a similar expression pattern as that of ebna3c at both transcript and protein levels, suggesting a possible correlation. Further, EBV and H. pylori created a microenvironment that induced cell transformation and oncogenesis through dysregulation of the cell cycle regulatory (ccnd1, dapk3, pcna, and akt), GC marker (abl1, tff-2, and cdx2), cell migration (mmp3 and mmp7), DNA response (pRB, pten, and p53), and antiapoptotic (bcl2) genes in infected gastric epithelial cells through gankyrin. Our study provides a new insight into the interplay of two oncogenic agents (H. pylori and EBV) that leads to an enhanced carcinogenic activity in gastric epithelial cells through overexpression of gankyrin. IMPORTANCE In the present study, we evaluated the synergistic effects of EBV and H. pylori infection on gastric epithelial cells in various coinfection models. These coinfection models were among the first to depict the exposures of gastric epithelial cells to EBV followed by H. pylori; however, coinfection models exist that narrated the scenario upon exposure to H. pylori followed by that to EBV. We determined that a coinfection by EBV and H. pylori enhanced the expression of oncogenic protein gankyrin. The interplay between EBV and H. pylori promoted the oncogenic properties of AGS cells like elevated focus formation, cell migration, and cell proliferation through gankyrin. EBV and H. pylori mediated an enhanced expression of gankyrin, which further dysregulated cancer-associated genes such as cell migratory, tumor suppressor, DNA damage response, and proapoptotic genes.

Epstein-Barr Virus-associated Pulmonary Tumor: A Pediatric Case and Discussion of the Literature.

Epstein-Barr virus-associated smooth pulmonary tumor is a rare condition that mostly affects immunosuppressed patients. This case describes a young boy with a history of kidney transplantation who presented recurrent pneumonia. Multiple endobronchial soft tissue tumors affecting both right and left bronchial tree were found and partially removed by bronchoscopy. Immunohistologic analysis demonstrated Epstein-Barr virus-associated smooth pulmonary tumor. Immunosuppressive therapy was changed from tacrolimus to sirolimus. A few months later, new right upper lobe and inferior left lobe tumors were found. Recurrent left lower lobe pneumonia prompted lobectomy. In the present case, complete resection and change of immunosuppressive treatment were effective.

The circuitry of the tumor microenvironment in adult and pediatric Hodgkin lymphoma: cellular composition, cytokine profile, EBV, and exosomes.

BACKGROUND: Classical Hodgkin lymphoma (cHL) is a unique lymphoid malignancy with a tumor microenvironment (TME) consisting of a small number of neoplastic-Hodgkin and Reed-Sternberg (H-RS) cells (<1%), surrounded by a large number of nonneoplastic infiltrating immune cells (>90%). The TME of cHL critically depends on immune cells to support tumor growth as H-RS cells cannot survive and proliferate in isolation. RECENT FINDINGS: Programmed cell death protein 1 (PD-1) ligand expressed on H-RS cells inhibits the clearance of tumor by causing T-cell exhaustion. Nivolumab and pembrolizumab, PD-1 inhibitors, have been proven to be effective in treating adult and pediatric patients with R/R cHL. Tumor-associated macrophages (TAMs) are a central component of TME and are known to cause poor prognosis in adult HL. However, the prognostic impact of CD68+ TAMs in pediatric HL remains ambiguous. EBV modulates the tumor milieu of HL and plays a strategic role in immune escape by enrichment of the TME with Treg cells and associated immunosuppressive cytokines in adult HL. In contrast, EBV+ pediatric patients have increased infiltration of CD8+ T-cells and show a better therapeutic response suggesting viral-related TME is distinct in childhood HL. The role of CASP3 in apoptosis of H-RS cells and its correlation with response prediction in adult and pediatric HL suggest it may serve as a potential biomarker. In cHL, CD30, EBV, and NF-κB signaling employ exosomes for cell-cell communication that triggers the migration capacity of fibroblasts, stimulate to produce proinflammatory cytokines, and help to create a tumor-supportive microenvironment. CONCLUSION: The cHL microenvironment is distinct in adult and pediatric HL. Future studies are required to understand the role of interplay between H-RS cells and EBV-associated microenvironment and their clinical outcome. They may present novel therapeutic targets for the development of antilymphoma therapy.

Status of kinases in Epstein-Barr virus and Helicobacter pylori Coinfection in gastric Cancer cells.

BACKGROUND: Helicobacter pylori (H. pylori) and Epstein - Barr virus (EBV) plays a significant role in aggressive gastric cancer (GC). The investigation of genes associated with these pathogens and host kinases may be essential to understand the early and dynamic progression of GC. AIM: The study aimed to demonstrate the coinfection of EBV and H. pylori in the AGS cells through morphological changes, expression of the kinase and the probable apoptotic pathways. METHODS: Genomic DNA isolation of H. pylori and its characterization from clinical samples were performed. RT-qPCR of kinases was applied to scrutinize the gene expression of kinases in co-infected GC in a direct and indirect (separated through insert size 0.45 µm) H. pylori infection set up. Morphological changes in co-infected GC were quantified by measuring the tapering ends of gastric epithelial cells. Gene expression profiling of apoptotic genes was assessed through RT-qPCR. RESULTS: An interleukin-2-inducible T-cell kinase (ITK) showed significant upregulation with indirect H. pylori infection. Moreover, Ephrin type-B receptor six precursors (EPHB6) and Tyrosine-protein kinase Fyn (FYN) showed significant upregulation with direct coinfection. The tapering ends in AGS cells were found to be extended after 12 h. A total of 24 kinase genes were selected, out of which EPHB6, ITK, FYN, and TYK2 showed high expression as early as 12 h. These kinases may lead to rapid morphological changes in co-infected gastric cells. Likewise, apoptotic gene expression such as APAF-1 and Bcl2 family genes such as BAD, BID, BIK, BIM, BAX, AND BAK were significantly down-regulated in co-infected AGS cells. CONCLUSION: All the experiments were performed with novel isolates of H. pylori isolated from central India, for the functional assessment of GC. The effect of coinfection with EBV was more profoundly observed on morphological changes in AGS cells at 12 h as quantified by measuring the tapering of ends. This study also identifies the kinase and apoptotic genes modulated in co-infected cells, through direct and indirect approaches. We report that ITK, EPHB6, TYK2, FYN kinase are enhanced, whereas apoptotic genes such as APAF-1, BIK, FASL, BAX are significantly down-regulated in AGS cells coinfected with EBV and H. pylori.

Gastric cancer: genome damaged by bugs.

Gastric cancer (GC) is one of the leading causes of cancer-related death worldwide. The role of the microorganisms in gastric tumorigenesis attracts much attention in recent years. These microorganisms include bacteria, virus, and fungi. Among them, Helicobacter pylori (H. pylori) infection is by far the most important risk factor for GC development, with special reference to the early-onset cases. H. pylori targets multiple cellular components by utilizing various virulence factors to modulate the host proliferation, apoptosis, migration, and inflammatory response. Epstein-Barr virus (EBV) serves as another major risk factor in gastric carcinogenesis. The virus protein, EBER noncoding RNA, and EBV miRNAs contribute to the tumorigenesis by modulating host genome methylation and gene expression. In this review, we summarized the related reports about the colonized microorganism in the stomach and discussed their specific roles in gastric tumorigenesis. Meanwhile, we highlighted the therapeutic significance of eradicating the microorganisms in GC treatment.

New Viral Facets in Oral Diseases: The EBV Paradox.

The oral cavity contributes to overall health, psychosocial well-being and quality of human life. Oral inflammatory diseases represent a major global health problem with significant social and economic impact. The development of effective therapies, therefore, requires deeper insights into the etiopathogenesis of oral diseases. Epstein-Barr virus (EBV) infection results in a life-long persistence of the virus in the host and has been associated with numerous oral inflammatory diseases including oral lichen planus (OLP), periodontal disease and Sjogren's syndrome (SS). There is considerable evidence that the EBV infection is a strong risk factor for the development and progression of these conditions, but is EBV a true pathogen? This long-standing EBV paradox yet needs to be solved. This review discusses novel viral aspects of the etiopathogenesis of non-tumorigenic diseases in the oral cavity, in particular, the contribution of EBV in OLP, periodontitis and SS, the tropism of EBV infection, the major players involved in the etiopathogenic mechanisms and emerging contribution of EBV-pathogenic bacteria bidirectional interaction. It also proposes the involvement of EBV-infected plasma cells in the development and progression of oral inflammatory diseases. A new direction for preventing and treating these conditions may focus on controlling pathogenic EBV with anti-herpetic drugs.

Gut Microbiota Functional Biomolecules With Immune-Lipid Metabolism for a Prognostic Compound Score in Epstein-Barr Virus-Associated Gastric Adenocarcinoma: A Pilot Study.

OBJECTIVE: Increasing evidence has indicated an association between gut microbiota in gastrointestinal cancer and clinical outcome. Herein, we aim to develop a prognosis-prediction tool based on an immune-lipid metabolism signature, tumor cell-associated immune microenvironment, and lipid metabolism proteins inferred from the function of gut microbiota. METHODS: 16S gene ribosomal RNA sequencing was performed on 10 fecal samples obtained after tumor resection but before chemotherapy (EBVaGC = 4 and EBVnGC = 6). Least absolute shrinkage and selection operator (LASSO) Cox regression was applied to screening for highly accurate marker proteins. A compound score based on the fraction of screened markers was then constructed using a LASSO logistic regression model. RESULTS: The Tax4Fun analysis based on Kyoto Encyclopedia of Genes and Genomes data indicated differentially expressed tumor pathway between EBVnGC and EBVaGC. Using the LASSO logistic model, a compound score was established consisting of 14 types of immune microenvironment and lipid metabolism proteins. In the training set (378 patients), significant differences were found between high- and low-compound score groups in overall survival across and within subpopulations with an identical EBV. Multivariable analysis revealed that the compound score was an independent prognostic factor (hazard ratio, 2.26; 95% confidence interval = 2.28-3.36). The prognostic value ;of the compound score was also confirmed in the validation (162 patients) and entire (540 patients) sets. DISCUSSION: The proposed compound score is a promising signature for estimating overall survival in patients with gastric cancer having EBVaGCs or EBVnGCs.

Multiple infections by EBV, HCMV and Helicobacter pylori are highly frequent in patients with chronic gastritis and gastric cancer from Southwest Mexico: An observational study.

The chronic inflammation and damage to the gastric epithelium induced by Helicobacter pylori (H. pylori) are the main risk factors for gastric cancer development. Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) induce chronic inflammation and have been found in gastric tumors. The objectives this observational study were to determine the frequency of multiple infections by Helicobacter pylori, Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) and to relate the infection by EBV and HCMV with H. pylori vacA/cagA genotypes in patients with chronic gastritis or gastric cancer. DNA from H. pylori, EBV and HCMV was detected by PCR in biopsies from 106 Mexican patients with chronic gastritis and 32 from gastric cancer. The cagA status and the vacA genotypes of H. pylori were determined by PCR. In chronic gastritis and gastric cancer EBV was found in 69.8% and 87.5%, HCMV in 52.8% and 53.1%, and H. pylori in 48.1% and 40.6%, respectively. In chronic gastritis, 53% of H. pylori patients were EBV and 33% were both EBV/HCMV; in gastric cancer, 92.3% of H. pylori-infected individuals were EBV and 46.1% were EVB/HCMV. All the intestinal- and mixed-type tumors and the 83.3% of diffuse-type tumors were EBV. No significant differences were found between single infections or coinfections with the diagnosis or the cancer type. The H. pylori genotypes were not related to EBV or HCMV infection. The frequency of dual infections by H. pylori, EBV and HCMV is higher in patients from southwest Mexico than other populations. It is likely that these pathogens act synergistically to induce inflammation and gastric cancer.

Risk factors for esophageal cancer: emphasis on infectious agents.

Risk factors for esophageal cancer include genetic factors (such as tylosis) and infectious agents. A variety of organisms have been implicated in esophageal carcinogenesis, either directly or indirectly. In this review, we explore the normal esophageal flora and how it may be controlled, and also the variety of organisms that may affect esophageal carcinogenesis, either directly or indirectly. The organisms with potential direct effects in squamous cell carcinoma include human papillomavirus (HPV), Epstein-Barr virus, and polyoma viruses. Interestingly, HPV is now implicated in esophageal adenocarcinoma (EAC), not in its initiation but in the development of dysplasia, in which HPV33 in particular has been associated. Indirectly, Helicobacter pylori has been associated with EAC by, initially, causing increased acid secretion that increases acid reflux, and by reducing lower esophageal sphincter pressure, which increases gastroesophageal reflux; the latter increases the risk of Barrett's esophagus, and hence EAC. Conversely, subsequent atrophic gastritis may normalize that risk.

Posttransplant Lymphoproliferative Disorders in Epstein-Barr Virus Donor Positive/Recipient Negative Lung Transplant Recipients.

BACKGROUND: Epstein-Barr virus (EBV) donor positive/recipient negative (D+/R-) status is a significant risk factor for posttransplant lymphoproliferative disorder (PTLD) in lung transplant. There are, however, no studies that identify the risk factors for PTLD in the EBV D+/R- lung transplant population to guide the decision to proceed with an EBV-positive donor. METHODS: This was a retrospective cohort study of adults listed in the Scientific Registry of Transplant Recipients between May 5, 2005, and August 31, 2016. Cox proportional hazards models were used to assess the impact of EBV D+/R- status on the development of PTLD, the impact of PTLD on survival, and survival differences between EBV D+/R- and EBV D-/R- recipients. RESULTS: The incidence of PTLD was 6.2% (79 of 1,281) versus 1.4% (145 of 10,352) in EBV D+/R- versus all other recipients (adjusted odds ratio 4.0; 95% confidence interval: 2.8 to 5.9, p < 0.001). Among EBV D+/R- recipients, age less than 40 years and white race were associated with PTLD. The EBV D+/R- patients who had PTLD had increased adjusted risk of death (hazard ratio 1.91; 95% confidence interval: 1.35 to 2.71; p < 0.001). Compared with EBV D+/R- recipients, EBV D-/R- recipients did not have improved adjusted survival (hazard ratio 0.82; 95% confidence interval: 0.57 to 1.18; p = 0.30). CONCLUSIONS: Despite increased rates of PTLD and associated mortality in the EBV D+/R- population, EBV seronegative patients did not have worse mortality when transplanted with lungs from EBV seropositive donors compared with lungs from EBV seronegative donors. Consideration should be given for close monitoring for PTLD among EBV D+/R- recipients, particularly those who are white and less than 40 years of age.

Pathogenesis of Gastric Cancer: Genetics and Molecular Classification.

Gastric cancer is the fifth most incident and the third most common cause of cancer-related death in the world. Infection with Helicobacter pylori is the major risk factor for this disease. Gastric cancer is the final outcome of a cascade of events that takes decades to occur and results from the accumulation of multiple genetic and epigenetic alterations. These changes are crucial for tumor cells to expedite and sustain the array of pathways involved in the cancer development, such as cell cycle, DNA repair, metabolism, cell-to-cell and cell-to-matrix interactions, apoptosis, angiogenesis, and immune surveillance. Comprehensive molecular analyses of gastric cancer have disclosed the complex heterogeneity of this disease. In particular, these analyses have confirmed that Epstein-Barr virus (EBV)-positive gastric cancer is a distinct entity. The identification of gastric cancer subtypes characterized by recognizable molecular profiles may pave the way for a more personalized clinical management and to the identification of novel therapeutic targets and biomarkers for screening, prognosis, prediction of response to treatment, and monitoring of gastric cancer progression.

The Participation of p53 and bcl-2 Proteins in Gastric Carcinomas Associated with Helicobacterpylori and/or Epstein-Barr Virus (EBV).

In the presented studies p53 and bcl-2 proteins expression were evaluated in samples of gastric carcinomas in patients with Helicobacter pylori or EBV or without H. pylori/EBV infection. The studies were conducted on 64 adult patients with gastric adenocarcinomas: 16 patients with H. pylori (cagA+)-positivity (group 1), 14 with EBV-positive tumours (group 2), 12 with H. pylori/EBV-positive tumours (group 3) and 22 patients with H. pylori/EBV-negative tumours (group 4). H. pylori presence in gastric tumour specimens was detected using Giemsa staining and bacterial culture technique. Moreover, cagA gene was detected using PCR. EBV infection was detected based on EBER presence in the tissue by RNA in situ hybridization. Expressions of p53 and bcl-2 proteins were analysed using immunohistochemistry. Expression of p53 was noted in 14 (84%) patients from group 1, 8 (57%) patients from group 2, 7 (58%) patients from group 3, and 19 (86%) patients from group 4, whereas expression of bcl-2 was noted in 12 (75%) patients from group 1, in 10 (71%) patients from group 2, 9 (75%) patients from group 3, and 6 (27%) patients from group 4. The obtained results allow the conclusion, that H. pylori (cagA+)-associated development of the gastric adenocarcinoma is determined by abnormalities in the p53 protein function and overexpression of anti-apoptotic bcl-2 protein, whereas EBV-associated adenocarcinomas seem to be related with apoptosis resistance associated with bcl-2 overexpression.

Case­control study of Epstein­Barr virus and Helicobacter pylori serology in Latin American patients with gastric disease.

BACKGROUND: Chronic tissue damage induced by Helicobacter pylori (HP)-driven inflammation is considered the main risk of gastric carcinoma (GC). Epstein­Barr virus (EBV) infection has also been associated with GC. In this study, we aim to address the role of EBV in inflammatory GC precursor lesions and its added risk to HP infection. METHODS: Antibodies against EBV, HP and the bacterial virulence factor CagA were measured in sera from 525 Mexican and Paraguayan patients with gastric disease. Gastric samples were characterised according to the updated Sydney classification and associations were estimated between antibody responses and severity of both tissue damage and inflammation. RESULTS: We found significant associations (odd ratios and trends) between EBV and HP copositivity and premalignant lesions and intestinal-type GC. The EBV and HP coinfection was also significantly associated with increased infiltration of immune cells. No association was found between EBV and the less inflammation-driven diffuse-type GC. CONCLUSIONS: Our study suggests that EBV co-participates with HP to induce severe inflammation, increasing the risk of progression to intestinal-type GC.

[The age aspects of clinical and morphological features of chronic gastritis viral and bacterial etiology].

The article contains the results of studies of clinical and morphological features of chronic gastritis of viral and bacterail etiology in age aspects. Chronic gastritis when infected with Epstein-Barr virus in elderly patients has clinical and morphological differences from chronic gastritis associated with Helicobacter pylori infection, consisting in significantly lower severity of regenerative changes in the cervical epithelium of the mucous membrane of the body and antrum of the stomach, cervical mucosal epithelium of the body, antrum, bottom mucosal epithelium of the stomach body; and significantly more rare intestinal metaplasia in the stomach and the absence of stromal fibrosis antrum.

[Apoptogenic activity of microbes-associants during Epstein-Barr virus infection].

AIM: Study apoptogenic activity of-microbes-associants during Epstein-Barr virus infection (EBVI) on the model of mice peritoneal macrophages in vitro. MATERIALS AND METHODS: Evaluation of apoptosis induced by bacteria isolated from EBVI patients was carried out by characteristic morphological changes of macrophages in smears stained by May-Grunwald with additional staining by Romanowsky-Giemsa. RESULTS: All the EBVI microbes-associants were established to have apoptogenic activity, however, the highest pathogenic potential was noted in Streptococcus pyogenes. CONCLUSION: The presence of apoptogenic activity in bacterial microflora accompanying EBVI against immune system cells could serve as means of their survival and be the pathogenetic basis for prolonged persistence in the organism.

[Clinical case. Chronic gastritis associated with Helicobacter pylori and Epstein-Barr virus].

The article describes a clinical case of chronic gastritis associated with Helicobacter pylori infection and Epstein-Barr virus. The authors draw attention to the peculiarities of dyspepsia syndrome, on the characteristics of this disease in the endoscopic and morphological study.

[Cycloferon in complex therapy management of chronic laryngitis].

The clinical course of various forms of chronic laryngitis, including contact granulomas not only persistant and relapsing, but also inclined to oncologic pathology due to hyperplastic changes in the larynx resulting in malignization was described. Inhibition of the leukocyte interferon-synthesizing activity was observed in more than 88.1% of the subjects. Pathogenic viruses were isolated from 48.2% of the patients, EBV and mycoplasma prevailing. High direct correlation between chronic laryngitis and Herpes viruses was shown. The presence of three-component virus associations in the larynx mucosa was likely indicative of the bening process malignancy. The use of the interferon inductor cycloferon in the complex surgical and medicamentous management of chronic laryngitis was shown valid. The rate of the relapses lowered to 1.7 episodes a year.