Latent Membrane Protein 1 Expression Research Articles

Targeting the LMP1-ALIX axis in EBV+ nasopharyngeal carcinoma inhibits immunosuppressive small extracellular vesicle secretion and boosts anti-tumor immunity.

Immunotherapy has revolutionized the therapeutical regimen for nasopharyngeal carcinoma (NPC), yet its response rate remains insufficient. Programmed death-ligand 1 (PD-L1) on small extracellular vesicles (sEVs) mediates local and peripheral immunosuppression in tumors, and the mechanism of PD-L1 loading into these vesicles is garnering increasing attention. Latent membrane protein 1 (LMP1), a key viral oncoprotein expressed in Epstein-Barr virus (EBV)-positive NPC, contributes to remodeling the tumor microenvironment. However, the precise mechanisms by which LMP1 modulates tumor immunity in NPC remain unclear. Here, we aimed to investigate the roles and regulatory mechanisms of LMP1 and sEV PD-L1 in NPC immune evasion. We analyzed the impact of LMP1 on tumor-infiltrating lymphocyte abundance in NPC tissues and humanized tumor-bearing mouse models using multiplex immunofluorescence (mIF) and flow cytometry, respectively. Transmission electron microscopy and nanoparticle tracking analysis were employed to characterize sEVs. Immunoprecipitation-mass spectrometry was utilized to identify proteins interacting with LMP1. The regulatory effects of sEVs on tumor microenvironment were assessed by monitoring CD8+ T cell proliferation and interferon-γ (IFN-γ) expression via flow cytometry. Furthermore, the expression patterns of LMP1 and downstream regulators in NPC were analyzed using mIF and survival analysis. High LMP1 expression in NPC patient specimens and mouse models was associated with restricted infiltration of CD8+ T cells. Additionally, LMP1 promoted sEV PD-L1 secretion, leading to inhibition of CD8+ T cell viability and IFN-γ expression in vitro. Mechanistically, LMP1 recruited apoptosis-linked gene 2-interacting protein X (ALIX) through its intracellular domain and bound PD-L1 through its transmembrane domain, thereby facilitating the loading of PD-L1 into ALIX-dependent sEVs. Disruption of ALIX diminished LMP1-induced sEV PD-L1 secretion and enhanced the anti-tumor immunity of CD8+ T cells both in vitro and in vivo. Moreover, increased expression levels of LMP1 and ALIX were positively correlated with enhanced immunosuppressive features and worse prognostic outcomes in NPC patients. Our findings uncovered the mechanism by which LMP1 interacts with ALIX and PD-L1 to form a trimolecular complex, facilitating PD-L1 loading into ALIX-dependent sEV secretion pathway, ultimately inhibiting the anti-tumor immune response in NPC. This highlights a novel target and prognostic marker for NPC immunotherapy.

Vaccination against Epstein-Barr Latent Membrane Protein 1 Protects against an Epstein-Barr Virus-Associated B Cell Model of Lymphoma.

In this study, we demonstrate that expression of viral latent membrane protein 1 (LMP1) in a mouse B cell line renders the animals responsive to protection from a 38C13-LMP1 tumor challenge with a novel vaccine. The Epstein-Barr virus (EBV) preferentially infects circulating B lymphocytes, has oncogenic potential, and is associated with a wide variety of B cell lymphomas. EBV is ectotrophic to human cells, and currently there are no B cell animal models of EBV-associated lymphoma that can be used to investigate vaccine immunotherapy. Since most EBV-infected human tumor cells express latent membrane protein 1 (LMP1) on their surface, this viral antigen was tested as a potential target for an anticancer vaccine in a mouse model. Here, we describe a new mouse model of LMP1-expressing B cell lymphoma produced with plasmid transduction of 38C13 into mouse B cells. The expression of LMP-1 was confirmed with a western blot analysis and immunocytochemistry. We then designed a novel LMP1 vaccine, by fusing viral antigen LMP1 surface loop epitopes to the surface of a viral antigen carrier, the Tobacco Mosaic virus (TMV). Vaccinated mice produced high titer antibodies against the TMV-LMP1 vaccine; however, cellular responses were at the baseline, as measured with IFNγ ELISpot. Despite this, the vaccine showed significant protection from a 38C13-LMP1 tumor challenge. To provide additional immune targets, we compared TMV-LMP1 peptide immunization with DNA immunization with the full-length LMP1 gene. Anti-LMP1 antibodies were significantly higher in TMV-LMP1-vaccinated mice compared to the DNA-immunized mice, but, as predicted, DNA-vaccinated mice had improved cellular responses using IFNγ ELISpot. Surprisingly, the TMV-LMP1 vaccine provided protection from a 38C13-LMP1 tumor challenge, while the DNA vaccine did not. Thus, we demonstrated that LMP1 expression in a mouse B cell line is responsive to antibody immunotherapy that may be applied to EBV-associated disease.

Epstein-Barr virus in breast carcinoma and in triple negative cases impact on clinical outcomes.

The contribution of viral infection in tumors pathogenesis has currently attracted attention. Epstein-Barr virus is an infectious agent involved in numerous human malignancies, including breast cancer. Although, their prognostic impact in breast tumor is rarely investigated. Therefore, we sought in our study to evaluate the prevalence of EBV in Tunisian breast carcinoma and to examine their potential association with clinicopathological features and overall survival. Our retrospective study included 100 formalin fixed paraffin embedded samples from Tunisian breast carcinoma. EBV infection was evaluated by immunohistochemical analysis, using monoclonal antibody against latent membrane protein 1 (LMP-1) and polymerase chain reaction. A subset of PCR positive specimens was subjected to in situ hybridization for the detection of EBER expression. Biomarker's expression was evaluated by immunohistochemistry method. Statistical analysis was also explored. The expression status of ER, PR and HER2 was 81%, 71.4% and 33.7% respectively. The triple negative profile was present in 10.84% of cases. LMP-1 expression was negative in all breast cancer specimens. PCR assay showed that 44% of patients were positive for EBV genome. None of the 15 PCR positive cases showed positive results for EBV by ISH. According to the molecular phenotype, there was a statistically significant difference in EBV DNA prevalence between breast cancer subgroups including TN (67%), Lum B (64%), HER2+(50%) and Lum A (30%). Bivariate analysis showed that EBV DNA was significantly associated with HER2+(p=0.035), tumor size (p=0.018) and high SBR grade (p=0.009). Multiple logistic regression analysis confirms the positive correlation of EBV with tumor size (p=0.048) and SBR grade (p=0.042). Kaplan-Meier analysis showed that patients with EBV+had significantly shorter overall survival than those with EBV- (p=0.032). Our study demonstrated the presence of EBV DNA in Tunisian breast carcinoma. EBV DNA was associated with aggressive features and poor overall survival. Further investigations will be required in large samples size to clarify the potential role of EBV in breast tumor progression.

Epstein-Barr Virus B Cell Growth Transformation: The Nuclear Events.

Epstein-Barr virus (EBV) is the first human DNA tumor virus identified from African Burkitt's lymphoma cells. EBV causes ~200,000 various cancers world-wide each year. EBV-associated cancers express latent EBV proteins, EBV nuclear antigens (EBNAs), and latent membrane proteins (LMPs). EBNA1 tethers EBV episomes to the chromosome during mitosis to ensure episomes are divided evenly between daughter cells. EBNA2 is the major EBV latency transcription activator. It activates the expression of other EBNAs and LMPs. It also activates MYC through enhancers 400-500 kb upstream to provide proliferation signals. EBNALP co-activates with EBNA2. EBNA3A/C represses CDKN2A to prevent senescence. LMP1 activates NF-κB to prevent apoptosis. The coordinated activity of EBV proteins in the nucleus allows efficient transformation of primary resting B lymphocytes into immortalized lymphoblastoid cell lines in vitro.

A STUDY ON EXPRESSION OF LATENT MEMBRANE PROTEIN 1 OF EPSTEIN BARR VIRUS IN NASOPHARYNGEAL CARCINOMA IN SOUTH INDIA

Background- Nasopharyngeal carcinoma arises from the nasopharynx epithelial lining and is caused by Epstein Barr virus. Latent Membrane Protein 1(LMP 1) expressed on cytoplasmic portion of cell surface of Epstein Barr virus is an oncoprotein which triggers multiple cell signalling pathways and facilitates the expression of virus infected cell population at an early stage of development of nasopharyngeal carcinoma. Aims and Objectives- To study the age,sex distribution, clinical presentation, histologic spectrum and expression of LMP1 in the histologic types of nasopharyngeal carcinoma. The present study is a cross sectional study done over a Material And Methods- period of two years at a tertiary care hospital.Histologic typing of nasopharyngeal carcinoma done on light microscopy followed by expression of Latent Membrane Protein 1 by Immunohistochemistry. The present study showed a male predominance (75%), bimodal age Results- distribution in second and fth decades of life, presented most commonly as nasal obstruction (82.5%), non keratinising undifferentiated type being the commonest histologic type (80%) and LMP 1 expression in 45% of cases. The detection of Latent Membrane Protei Conclusion- n 1 by immunohistochemistry helps in early diagnosis of nasopharyngeal carcinoma and may aid in treatment as a therapeutic target

Oncogenic role of LMP1 expression in Epstein-Barr virus associated with nasopharyngeal carcinoma: A literature review

Nasopharyngeal carcinoma (NPC) is a malignant carcinoma that appears in the epithelial lining of the nasopharyngeal mucosa. Genetic predisposition, environmental risk factors, nutritional risk factors, and Epstein-Barr virus (EBV) infection are the main risk factors for NPC. Epstein-Barr virus, a human cancer-associated virus, is present in more than 90% of people worldwide. Latent Membrane Protein 1 (LMP1) has been identified as the main Epstein-Barr virus converting oncoprotein. LMP1 was shown to be present in NPC tumor tissues, suggesting a potential role for LMP1 in EBV-mediated carcinogenesis. LMP1 exerts several oncogenic properties and has the ability to transform epithelial cells through the activation of numerous signaling pathways and the control of the expression of different oncogenes and tumor-suppressor genes. the process by which tumor traits such cell proliferation, apoptosis resistance, invasion and motility, and angiogenesis are produced and maintained.

Cyclophilin A binds to AKT1 and facilitates the tumorigenicity of Epstein-Barr virus by mediating the activation of AKT/mTOR/NF-κB positive feedback loop.

The AKT/mTOR and NF-κB signalings are crucial pathways activated in cancers including nasopharyngeal carcinoma (NPC), which is prevalent in southern China and closely related to Epstein-Barr virus (EBV) infection. How these master pathways are persistently activated in EBV-associated NPC remains to be investigated. Here we demonstrated that EBV-encoded latent membrane protein 1 (LMP1) promoted cyclophilin A (CYPA) expression through the activation of NF-κB. The depletion of CYPA suppressed cell proliferation and facilitated apoptosis. CYPA was able to bind to AKT1, thus activating AKT/mTOR/NF-κB signaling cascade. Moreover, the use of mTOR inhibitor, rapamycin, subverted the activation of the positive feedback loop, NF-κB/CYPA/AKT/mTOR. It is reasonable that LMP1 expression derived from initial viral infection is enough to assure the constant potentiation of AKT/mTOR and NF-κB signalings. This may partly explain the fact that EBV serves as a tumor-promoting factor with minimal expression of the viral oncoprotein LMP1 in malignancies. Our findings provide new insight into the understanding of causative role of EBV in tumorigenicity during latent infection.

Repression of DERL3 via DNA methylation by Epstein-Barr virus latent membrane protein 1 in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is Epstein-Barr virus (EBV)-associated invasive malignancy. Increasing evidence indicates that epigenetic abnormalities, including DNA methylation, play important roles in the development of NPC. In particular, the EBV principal oncogene, latent membrane protein 1 (LMP1), is considered a key factor in inducing aberrant DNA methylation of several tumour suppressor genes in NPC, although the mechanism remains unclear. Herein, we comprehensively analysed the methylome data of Infinium BeadArray from 51 NPC and 52 normal nasopharyngeal tissues to identify LMP1-inducible methylation genes. Using hierarchical clustering analysis, we classified NPC into the high-methylation, low-methylation, and normal-like subgroups. We defined high-methylation genes as those that were methylated in the high-methylation subgroup only and common methylation genes as those that were methylated in both high- and low-methylation subgroups. Subsequently, we identified 715 LMP1-inducible methylation genes by observing the methylome data of the nasopharyngeal epithelial cell line with or without LMP1 expression. Because high-methylation genes were enriched with LMP1-inducible methylation genes, we extracted 95 high-methylation genes that overlapped with the LMP1-inducible methylation genes. Among them, we identified DERL3 as the most significantly methylated gene affected by LMP1 expression. DERL3 knockdown in cell lines resulted in significantly increased cell proliferation, migration, and invasion. Lower DERL3 expression was more frequently detected in the advanced T-stage NPC than in early T-stage NPC. These results indicate that DERL3 repression by DNA methylation contributes to NPC tumour progression.

Correlation Between Immunohistochemical Expression of Epstein-Barr Virus Latent Membrane Protein-1 (LMP-1) and Clinical Stages of Sinonasal Carcinoma

Introduction: Sinonasal tumors are rarely found. The protected nature of the sinuses makes early detection of tumors growing in these areas difficult. The Epstein-Barr virus is one of the most common viruses found in humans; which expresses Latent Membrane Protein-1 (LMP-1) that can transform cell lines and alter cell phenotype due to its oncogenic potential. Objective: To investigate the relationship between immunohistochemical expression of Latent Membrane Protein-1 (LMP-1) from Epstein-Barr virus and clinical stages of sinonasal carcinoma. Methods: This cross-sectional study was carried out in DR. Wahidin Sudirohusodo General Hospital and anatomic pathology of Hasanuddin University Hospital, Makassar, South Sulawesi, Indonesia, from October 2016 to March 2017. Histopathological samples from biopsy specimen of all subjects diagnosed with sinonasal carcinoma in Otorhinolaryngology-Head and Neck Surgery outpatient clinic were taken and examined for LMP-1 expression using immunohistochemical staining. The samples were taken from paraffin block from patients. Result: There were 33 males (67.3%) and 16 females (32.7%) with sinonasal carcinoma who participated in this study. The majority of participants aged ≥50 years (25 people, 51.0%) and worked as farmers (27 people, 55.1%). A significant correlation between LMP-1 expression and sinonasal carcinoma clinical stages was found (Spearman’s correlation r = 0.355 and p <0.001). Conclusion: Higher LMP-1 expression correlates with higher sinonasal carcinoma clinical stage in patients aged <50 years.

Clinicopathologic study of mantle cell lymphoma with epstein-barr virus infection: A case series and literature review.

BackgroundMantle cell lymphoma (MCL) with Epstein–Barr virus (EBV) infection is rarely reported. The objective of this study was to analyze the prevalence and clinicopathological features of MCL with EBV infection in the largest series thus far.MethodsAfter screening 138 cases of MCL, we identified eight cases of MCL with EBV infection.ResultsMost of them (7/8) had non-neoplastic bystander cells with positivity for EBV and no expression of latent membrane protein 1 (LMP1) and EBV nuclear antigen 2 (EBNA2). The cases of MCL with EBER positivity did not have abnormal immune function or other lymphomas. Moreover, their histopathological morphology was indicative of classical MCL. Cases of MCL with EBER positivity exhibited statistically significant differences in lactate dehydrogenase, anemia status, and MCL international prognostic index grouping (P=0.008, P=0.02, P=0.001, and P=0.011, respectively). The differences between the two groups in age, sex ratio, clinical manifestations, and immunohistochemical phenotypes were not statistically significant.ConclusionsThe incidence of MCL with EBV infection was low (5.8%). Clinicopathologically, cases of MCL with EBER positivity were similar to their EBV-negative counterparts. Our findings revealed that most cells infected by EBV in MCL are background cells rather than tumor cells. This is inconsistent with data from previous studies, indicating that tumor cells in MCL may not be prone to EBV infection.

Study of Three Potential Diagnostic Biomarkers in Nasopharyngeal Carcinoma Samples from Guilan, North of Iran.

Introduction Finding biomarkers for highly lethal cancers is a priority. Objective The current study was designed to understand the clinical significance of vascular endothelial growth factor (VEGF), latent membrane protein 1 (LMP1), and tumor necrosis factor-α (TNF-α) expression as the biomarkers, and evaluate their correlation with each other, in nasopharyngeal carcinoma (NPC) in the province of Guilan, North of Iran. Methods Gene expression was evaluated in 25 formalin-fixed paraffin-embedded (FFPE) blocks from cases of confirmed NPC and 20 FFPE samples of non-NPC by quantifying messenger ribonucleic acid (mRNA) and protein levels, using real-time polymerase chain reaction (PCR) and immunohistochemistry (IHC) methods, respectively. Furthermore, the correlations among the protein levels of different genes, along with the patients' demographic characteristics were assessed. Results Our findings on mRNA and protein levels demonstrated that the expression of the LMP1 gene in the NPC group was significantly elevated compared with that of the non-NPC group. In addition, the protein levels in the NPC group indicated a positive and significant correlation between LMP1 and VEGF expression. It was noted that both protein and mRNA levels showed no significant differences in the expression of TNF-α and VEGF genes between the NPC and control groups. Furthermore, there was no significant relationship between the expression of these proteins and the demographic characteristics of NPC patients. Conclusion Overall, a significant increase in LMP1 expression was observed in NPC patients, which may serve as a diagnostic biomarker for NPC. Also, LMP1 might be involved in NPC progression by inducing VEGF gene expression.

The Prevalence and the Patterns of the Expression of Latent Epstein-Barr Virus in Hodgkin’s and Non-Hodgkin’s Lymphomas Among Patients in Oman: Immunohistochemistry Versus in Situ Hybridization.

Epstein Barr virus (EBV) has been incriminated in the pathogenesis of Hodgkin’s lymphoma (HL) and non-Hodgkin’s lymphoma (NHL). The present study aimed to investigate the prevalence and the pattern of the expression of Epstein-Barr in HL and NHL tissue samples obtained from Omani patients attending Sultan Qaboos University Hospital (SQUH). Besides, to compare the sensitivity and specificity of immunohistochemistry(IHC) and in situ hybridization (ISH) for the detection of EBV in HL and NHL and finally to have more understanding of the pathogenesis of EBV in HL and NHL among patients in Oman. Formalin-fixed paraffin-embedded tissue samples consisting of 26 Hodgkin and 34 non-Hodgkin lymphomas were assessed for the presence of EBV by IHC to detect Latent membrane protein (LMP), expression and by using ISH to detect Epstein -Barr encoded RNAs (EBERs). The expression of LMP and EBERs were detected respectively in 46.2% and 57.7% of Hodgkin’s lymphoma cases and were detected in 11.8% and 14.7% respectively of non-Hodgkin’s lymphoma cases. The intensity of LMP-1 and EBER expression was significantly high in mixed cellularity compared to other subtypes. The expression of EBV was detected in transformed cells in both HL & NHL. The expression of EBV in transformed cells in both HL and NHL indicates that EBV may play a pro vital role in the pathogenesis of HL and NHL among patients in Oman. Moreover, this study indicates that IHC is to some degree compatible in terms of sensitivity and specificity to ISH in the detection of EBV in HL and NHL.

L-Asparaginase synergizes with etoposide via the PI3K/Akt/mTOR pathway in Epstein-Barr virus-positive Burkitt lymphoma.

Burkitt lymphoma (BL) is an aggressive Epstein-Barr virus (EBV)-driven B-cell lymphoma characterized by the translocation and rearrangement of the c-Myc proto-oncogene. High-intensity multidrug chemotherapy regimens have a limited effect on the survival of refractory or relapsed BL patients, mainly owing to the high EBV load and drug resistance. l-asparaginase ( l-Asp) and etoposide (VP-16) play a beneficial role in EBV-related lymphoproliferative diseases; however, their roles and mechanisms in BL remain unclear. In this study, we found that VP-16 inhibited BL cell proliferation and arrested the cell cycle at the G2 /M phase. It also induced autophagy and activated the extrinsic and intrinsic apoptotic signaling pathways in BL cells. Mechanistically, VP-16 inhibited c-Myc expression and regulated the PI3K/Akt/mTOR signaling pathway. Notably, VP-16 also showed a specific synergistic effect with l-Asp to induce apoptosis in EBV-positive BL cells but not in EBV-negative BL cells. VP-16 combined with l-Asp further inhibited c-Myc expression and downregulated the PI3K/Akt/mTOR signaling pathway. Additionally, we found that VP-16 inhibited the expression of latent membrane protein 1 (LMP1), and in combination with l-Asp further decreased LMP1 expression in Raji cells. Our in vivo data also showed that the dual-drug combination significantly inhibited the growth of BL tumors and prolonged the survival of mice compared to VP-16 alone. In conclusion, this study provides new evidence that l-Asp may enhance the antitumor effect of VP-16 by inhibiting the PI3K/Akt/mTOR signaling pathway in EBV-positive BL cells.

Epstein-Barr Virus Latent Membrane Protein-1 Expression in Nasopharyngeal Carcinoma.

PURPOSENasopharyngeal carcinoma (NPC), a malignant neoplasm of the epithelium covering the nasopharynx, is a rare disease in most parts of the world. Epstein-Barr virus (EBV), the most potent oncogenic virus, coupled with environmental and genetic factors has been identified to play a role in the development of NPC. An array of methods for detecting the virus do exist, from serologic detection of antibodies to DNA amplification. There is paucity of local data on the status of EBV infection in relation to NPC within the region, and this study attempts to shed more light on the subject.METHODSThis was a retrospective cross-sectional laboratory-based study on histologically confirmed, archived tissues from July 2015 to June 2019. Immunohistochemistry expression of latent membrane protein-1 (LMP-1) was used to detect EBV infection in the tissues.RESULTSA total of 71 cases were enrolled in this study. The mean age was 47.87 years ± 16.84 years with a male-to-female ratio of 1.5:1. There was a unimodal distribution of EBV detection, with the peak (26.8%) at 36-45 years. About 45.1% of the 71 samples tested positive for LMP-1, all of which were nonkeratinizing carcinoma. Nonkeratinizing carcinoma was the most common histopathologic subtype (n = 67; 94.4%), with the majority (38 of 67; 56.7%) being undifferentiated and 29 of 67 (43.3%) differentiated. Keratinizing and basaloid subtypes had two cases each, representing 2.8%.CONCLUSIONA significant proportion of NPC, particularly nonkeratinizing histologic subtype, seems to show LMP-1 positivity by immunohistochemistry, which may be adopted in resource-constrained settings to detect EBV infection in these tissue biopsies.

()-Epigallocatechin-3-Gallate Inhibits EBV Lytic Replication via Targeting LMP1-Mediated MAPK Signal Axes.

Epstein–Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) plays an important oncogenic role in the viral latent infection. Recently, increasing evidence indicates that the high expression of LMP1 during EBV lytic cycle is related to the viral lytic replication. However, the mechanism by which LMP1 regulates EBV lytic replication remains unclear. (−)-Epigallocatechin-3-gallate (EGCG) prevents carcinogenesis by directly targeting numerous membrane proteins and effectively inhibits EBV lytic cascade. Here, we demonstrated that LMP1 promotes EBV lytic replication through the downstream signal molecules MAPKs, including ERKs, p38, and JNKs. LMP1 induces the phosphorylation of p53 through MAPKs to enhance the ability of wild-type p53 (wt-p53) to activate expression of BZLF1 gene, while the JNKs/c-Jun signal axis appears to be involved in EBV lytic replication induced by LMP1 in p53 mutant manner. We provided the first evidence that EGCG directly targets the viral membrane LMP1 (K d = 0.36 μM, n = 1) using fluorescence quenching, isothermal titration calorimetry (ITC) assay, and CNBR-activated Sepharose 4B pull-down affinity chromatography. Furthermore, we revealed that EGCG inhibits EBV lytic replication via suppressing LMP1 and thus blocking the downstream MAPKs/wt-p53 signal axis in AGS-EBV cells and JNKs/c-Jun signal axis in p53 mutant B95.8 cells. Our study, for the first time, reports the binding and inhibitory efficacy of EGCG to the LMP1, which is a key oncoprotein encoded by EBV. These findings suggest the novel function of LMP1 in the regulation of EBV lytic cycle and reveal the new role of EGCG in EBV-associated malignancies through suppressing viral reactivation.

The EBV-Encoded Oncoprotein, LMP1, Recruits and Transforms Fibroblasts via an ERK-MAPK-Dependent Mechanism

Latent membrane protein 1 (LMP1), the major oncoprotein encoded by Epstein–Barr virus (EBV), is expressed at widely variable levels in undifferentiated nasopharyngeal carcinoma (NPC) biopsies, fueling intense debate in the field as to the importance of this oncogenic protein in disease pathogenesis. LMP1-positive NPCs are reportedly more aggressive, and in a similar vein, the presence of cancer-associated fibroblasts (CAFs) surrounding “nests” of tumour cells in NPC serve as indicators of poor prognosis. However, there is currently no evidence linking LMP1 expression and the presence of CAFs in NPC. In this study, we demonstrate the ability of LMP1 to recruit fibroblasts in vitro in an ERK-MAPK-dependent mechanism, along with enhanced viability, invasiveness and transformation to a myofibroblast-like phenotype. Taken together, these findings support a putative role for LMP1 in recruiting CAFs to the tumour microenvironment in NPC, ultimately contributing to metastatic disease.

Expression Mechanism of miR-10b in Cervical Cancer Under Treatment of Methoxy-Polyethylene Glycol-Polylactic Drug-Loaded Nanoparticles

This work aimed to analyze expression mechanism of micro ribonucleic acid (RNA)-10b (miR-10b) in cervical cancer (CC) based on Curcumin-monomethoxy polyethylene glycol-polylactic acid-drug-loaded nanoparticles (CUR-MPEG-PLA DLNPs). 36 Kunming mice were selected and randomly rolled into group A and group B, and 18 nude mice were deemed as controls. CUR-MPEG-PLA DLNPs were prepared for the treatment of 18 Kunming mice in group A. The CC tumor tissues of 36 Kunming mice were harvested, the miR-10b of CC cells was extracted, and the expression level of CC cells was detected by fluorescence quantitative polymerase chain reaction (qPCR). The results showed that the average particle size of CUR-MPEG-PLA DLNPs was 362.52±6.34 nm. The tumor inhibition rate of Kunming mice in group A against CC tumor strains 63.35±3.62% was considerably superior to those in group B (26.31 ±2.54%) (P < 0.05). In group A, expression rate of miR-10b (77.78%) was remarkably superior to controls (55.55%) (x2 = 2.364, P < 0.05). In 20 cases of CC tissues with positive expression of latent membrane protein 1 (LMP-1), expression of miR-10b in metastasis group was obviously higher relative to non-metastasis group (Z = −3.214, P < 0.05). In 16 cases of CC tissues with negative expression of LMP-1, expression of miR-10b in metastasis group was also considerably higher versus non-metastasis group (Z = −2.245, P < 0.05). In conclusion, the average particle size of CUR-MPEG-PLA DLNPs was 362.52 ±6.34 nm, the electromotive force was −9.23 mV, the dispersion coefficient was 0.064, the drug loading rate of nanoparticles was 8.54%, and the encapsulation rate was 72.36%. miR-10b has certain correlation with the metastasis of cervical cancer. LMP-1 gene has the function of promoting the metastasis of cervical cancer tumor cells, which may be dependent on miR-10b. CUR-MPEG-PLA DLNPs loading system can inhibit tumor growth obviously, and has excellent therapeutic effect in CC disease.

Simultaneously Both Expression of LMP-1 and Methylation of E-cadherin: Molecular Biomarker in Stage IV of Nasopharyngeal Carcinoma Patients.

The phenome of E-cadherin gene methylation and the expression of latent membrane protein 1 (LMP-1) gene are associated with nasopharyngeal carcinoma (NPC). In order to determine whether cooperative LMP-1 expression or methylation of E-cadherin could serve as the potential molecule biomarker target for diagnosis and therapy of NPC, a case-control study including 93 NPC biopsy samples and 100 non cancerous nasopharyngeal swab samples were examined, as well as the strength of association among them by the quantitative polymerase chain reaction (qPCR) and nested-methylation-specific PCR methods. The significantly higher frequency of LMP-1 expression and E-cadherin methylation in NPC biopsy samples, accounting for 76.34 and 73.12%, respectively, compared to non cancerous samples, accounting for 0.00 and 30.00%, respectively, were observed. The significant correlation between the LMP-1 expression and E-cadherin methylation in NPC samples was reported. In detail, in the stage IV of NPC, in case of LMP-1-positive samples, 35 of 37 samples (accounting for 94.60%) were positive for methylation of E-cadherin. It was demonstrated that cooperative LMP-1 expression and E-cadherin gene methylation could serve as a molecular biomarker in NPC.

Epstein-Barr Virus LMP1 Induces Soluble PD-L1 in Nasopharyngeal Carcinoma.

Nasopharyngeal carcinoma (NPC) is an Epstein–Barr virus (EBV)-associated malignancy. The principal oncogene of EBV, latent membrane protein 1 (LMP1), induces the expression of programmed death-ligand 1 (PD-L1), which is an immunosuppressive transmembrane protein and a promising therapeutic target for various malignancies. Recent studies have revealed an association between the level of soluble PD-L1 (sPD-L1) and disease progression. However, the role of sPD-L1 in NPC or its relevance to LMP1 has not been elucidated. This study aimed to examine whether LMP1 induces sPD-L1 in vitro and analyze the clinical relevance of LMP1, PD-L1, and sPD-L1 in NPC patients. Analysis of nasopharyngeal cell lines revealed that LMP1 induces both cellular PD-L1 and sPD-L1. Analysis of biopsy specimens from 32 NPC patients revealed that LMP1 expression was significantly correlated with PD-L1 expression. Finally, the serum sPD-L1 level in NPC patients was higher than that in the controls. Moreover, the sPD-L1 level in the advanced stage was higher than that in the early stage. However, LMP1 expression, PD-L1 expression, and sPD-L1 levels were not associated with prognosis. These results suggest that LMP1 induces both sPD-L1 and PD-L1, which are associated with NPC progression.

Epstein-Barr Functional Mimicry: Pathogenicity of Oncogenic Latent Membrane Protein-1 in Systemic Lupus Erythematosus and Autoimmunity.

Systemic lupus erythematosus (SLE) and other autoimmune diseases are propelled by immune dysregulation and pathogenic, disease-specific autoantibodies. Autoimmunity against the lupus autoantigen Sm is associated with cross-reactivity to Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA-1). Additionally, EBV latent membrane protein-1 (LMP1), initially noted for its oncogenic activity, is an aberrantly active functional mimic of the B cell co-stimulatory molecule CD40. Mice expressing a transgene (Tg) for the mCD40-LMP1 hybrid molecule (containing the cytoplasmic tail of LMP1) have mild autoantibody production and other features of immune dysregulation by 2–3 months of age, but no overt autoimmune disease. This study evaluates whether exposure to the EBV molecular mimic, EBNA-1, stimulates antigen-specific and concurrently-reactive humoral and cellular immunity, as well as lupus-like features. After immunization with EBNA-1, mCD40-LMP1 Tg mice exhibited enhanced, antigen-specific, cellular and humoral responses compared to immunized WT congenic mice. EBNA-1 specific proliferative and inflammatory cytokine responses, including IL-17 and IFN-γ, were significantly increased (p<0.0001) in mCD40-LMP1 Tg mice, as well as antibody responses to amino- and carboxy-domains of EBNA-1. Of particular interest was the ability of mCD40-LMP1 to drive EBNA-1 associated molecular mimicry with the lupus-associated autoantigen, Sm. EBNA-1 immunized mCD40-LMP1 Tg mice exhibited enhanced proliferative and cytokine cellular responses (p<0.0001) to the EBNA-1 homologous epitope PPPGRRP and the Sm B/B’ cross-reactive sequence PPPGMRPP. When immunized with the SLE autoantigen Sm, mCD40-LMP1 Tg mice again exhibited enhanced cellular and humoral immune responses to both Sm and EBNA-1. Cellular immune dysregulation with EBNA-1 immunization in mCD40-LMP1 Tg mice was accompanied by enhanced splenomegaly, increased serum blood urea nitrogen (BUN) and creatinine levels, and elevated anti-dsDNA and antinuclear antibody (ANA) levels (p<0.0001 compared to mCD40 WT mice). However, no evidence of immune-complex glomerulonephritis pathology was noted, suggesting that a combination of EBV and genetic factors may be required to drive lupus-associated renal disease. These data support that the expression of LMP1 in the context of EBNA-1 may interact to increase immune dysregulation that leads to pathogenic, autoantigen-specific lupus inflammation.