Systematic comparison of plasma EBV DNA, anti-EBV antibodies and miRNA levels for early detection and prognosis of nasopharyngeal carcinoma

Viral Load Measurements for Kaposi Sarcoma Herpesvirus (KSHV/HHV8): Review and an Updated Assay

"When you can measure what you are speaking about, and express it in numbers, you know something about it." is a famous quote attributed to Lord Kelvin. This sentiment puts viral load measurements at the center of virology. Viral load, or more precisely, DNA copy number measurements, are also used to follow infections with human herpesviruses, such as Kaposi sarcoma herpesvirus (KSHV) and Epstein-Barr Virus (EBV). EBV and KSHV are associated with human cancers, and determining their DNA copy numbers in the context of cancer prediction and progression on therapy is of fundamental scientific and translational interest. Yet, there is no generally accepted assay for KSHV DNA quantitation, and KSHV viral load is not used in clinical decision-making. Here, we review the history of KSHV DNA detection assays, explore factors that affect sensitivity and specificity, and describe an automated, high-throughput, real-time quantitative polymerase chain reaction (PCR) assay for KSHV and EBV. In conjunction with a digital PCR assay using the same primer/probe combination, we describe how to determine the absolute KSHV genome copy numbers in plasma, peripheral blood mononuclear cells, saliva, and other easily accessible body fluids.

Increased CCT5 expression is a potential unfavourable factor promoting the growth of nasopharyngeal carcinoma

OBJECTIVE

Chaperonin containing TCP1 subunit 5 (CCT5) encodes the CCT5 protein subunit of chaperonin-containing TCP-1 (CCT/TRiC) complex, and is shown to be upregulated in tumour pathogenesis. The study aim was to investigate the differential expression of CCT5 between nasopharyngeal carcinoma (NPC) and noncancerous nasopharyngeal tissues, and the correlation between CCT5 expression and clinicopathological parameters/prognosis in patients with NPC.

METHODS

Microarray assay data were evaluated for differential expression between NPC and noncancerous nasopharyngeal tissues. CCT5 expression in NPC and noncancerous nasopharyngeal tissues was determined at mRNA and protein levels by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemistry. Relationships between CCT5 expression in NPC, clinical parameters, and prognosis were statistically analysed. CCT5-mediated cell proliferation was assessed using EdU and cell counting kit-8. Western blot and co-immunoprecipitation were utilized to explore E3 ubiquitin-protein ligase parkin (PARK2)-induced degradation of CCT5.

RESULTS

Microarray data showed CCT5 levels to be significantly increased in NPC versus noncancerous nasopharyngeal tissues, which was confirmed by qRT-PCR and immunohistochemical assays. Increased CCT5 protein levels positively correlated with tumour size, tumour recurrence, and clinical stage, and inversely correlated with patient's overall survival. Multivariate Cox regression analysis showed that enhanced CCT5 protein expression is an independent prognostic factor for patients with NPC. Overexpression of CCT5 markedly induced NPC cell proliferation. Finally, PARK2, as a suppressive E3 ubiquitin-ligase enzyme, was shown to bind CCT5 and induce degradation in NPC.

CONCLUSIONS

Increased CCT5 may be an unfavourable factor promoting NPC growth. Binding of PARK2 to CCT5 was associated with CCT5 degradation, suggesting that PARK2 is an upstream negative modulator in NPC.

Microfluidic bead-based biosensor: Ultrasensitive ctDNA detection based on duplex-functional split-DNAzyme and dendritic enzyme-free signal amplification

Circulating tumor DNA (ctDNA) is a crucial cancer biomarker for early or noninvasive monitoring, which is essential for developing ultrasensitive and selective assays in cancer diagnosis and treatment. Herein, a cascade signal amplification of duplex-functional split-DNAzyme and dendritic probes was proposed for ultrasensitive and specific detection of nasopharyngeal carcinoma-associated Epstein-Barr virus (EBV) DNA on microfluidic microbead array chips. With the assistance of Pb2+, the duplex-functional split-DNAzyme recognizes EBV DNA and then rapidly cleaves the substrate strand. Subsequently, the released target could be recycled, and its exposed capture probe, triggered the dendritic enzyme-free signal amplification. As the enhanced mass transfer capability, target recycling, and dendritic DNA structure signal amplification inherent to microfluidic bead arrays were integrated, it achieved an excellent detection limit of 0.36 fM and a wide linear range of 1 fM∼103 fM. Further, it was applied to content detect simulated samples of EBV DNA, recovery ranged from 97.2 % to 108.1 %, and relative standard deviation (RSD) from 3.3 % to 5.9 %, exhibiting satisfactory recovery results. The developed microfluidic biosensor was a high-sensitivity and anti-interference system for ctDNA analysis, with minimal reagent volumes (microlitres) required. Thus, it is a promising platform for ctDNA at the lowest level at their earliest incidence.

Plasma Epstein-Barr virus microRNA BART8-3p as a potential biomarker for detection and prognostic prediction in early nasopharyngeal carcinoma

Epstein-Barr virus (EBV) encoded microRNA BART8-3p (miR-BART8-3p) was significantly associated with the metastasis in nasopharyngeal carcinoma (NPC). To explore the clinical values of plasma miR-BART8-3p in patients with early NPC. We retrospectively analyzed 126 patients with stage I and II NPC. A receiver operating characteristic curve was used to examine the diagnostic performance. Kaplan‒Meier analysis was applied to determine survival differences. Cox regression was used for univariate and multivariate analyses. Compared to healthy subjects, plasma EBV miR-BART8-3p was highly expressed in early NPC patients. The sensitivity, specificity, and area under the curve value of plasma miR-BART8-3p combined with plasma EBV DNA was up to 88.9%, 94.4%, and 0.931. Compared to patients with low expression of miR-BART8-3p, patients with high expression of miR-BART8-3p had poorer 5-year overall survival (OS) (98.9% vs. 91.1%, P = 0.025), locoregional recurrence-free survival (LRRFS) (100% vs. 83.9%, P < 0.001) and distant metastasis-free survival (DMFS) (98.9% vs. 88.0%, P = 0.006). Risk stratification analysis revealed that high-risk patients (with high levels of EBV DNA and miR-BART8-3p) had inferior OS, LRRFS, and DMFS than low-risk patients (without high levels of EBV DNA and miR-BART8-3p). Multivariate analysis verified that the high-risk group was an unfavorable factor for OS, LRRFS, and DMFS. A combination of plasma EBV miR-BART8-3p and EBV DNA could be a potential biomarker for the diagnosis and prognosis in early NPC.

Precision Medicine for Nasopharyngeal Cancer-A Review of Current Prognostic Strategies

Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus (EBV) driven malignancy arising from the nasopharyngeal epithelium. Current treatment strategies depend on the clinical stage of the disease, including the extent of the primary tumour, the extent of nodal disease, and the presence of distant metastasis. With the close association of EBV infection with NPC development, EBV biomarkers have shown promise in predicting treatment outcomes. Among the omic technologies, RNA and miRNA signatures have been widely studied, showing promising results in the research setting to predict treatment response. The transformation of radiology images into measurable features has facilitated the use of radiomics to generate predictive models for better prognostication and treatment selection. Nonetheless, much of this work remains in the research realm, and challenges remain in clinical implementation.

Clinical significance of anti-Epstein-Barr virus antibodies in systemic chronic active Epstein-Barr virus disease

Systemic chronic active Epstein-Barr virus disease (sCAEBV) is a rare and fatal neoplasm, involving clonally proliferating Epstein-Barr virus (EBV)-infected T cells or natural killer cells. Patients with sCAEBV have abnormal titers of anti-EBV antibodies in their peripheral blood, but their significance is unknown. We retrospectively investigated titers and their relationship with the clinical features of sCAEBV using the data collected by the Japanese nationwide survey. Eighty-four patients with sCAEBV were analyzed. The anti-EBV nuclear antigen (EBNA) antibody, targeting EBNA-expressing EBV-positive cells, was found in 87.5% of children (<15 years old), 73.7% of adolescents and young adults (15-39 years old), and 100% of adults (≥40 years old). Anti-EBNA antibody titers were significantly lower and anti-VCA-IgG antibody titers significantly higher in patients with sCAEBV than those in healthy controls (p < 0.0001). Patients with high anti-VCA-IgG and anti-early antigen-IgG antibody (antibodies against the viral particles) levels had significantly better 3-year overall survival rates than those with low titers, suggesting that patients with sCAEBV have a reduced immune response to EBV-infected cells.

Multiple cross displacement amplification combined with nanoparticle-based lateral flow biosensor for rapid and sensitive detection of Epstein-Barr virus

Introduction

Epstein-Barr virus (EBV) is a highly dangerous virus that is globally prevalent and closely linked to the development of nasopharyngeal cancer (NPC). Plasma EBV DNA analysis is an effective strategy for early detection, prognostication and monitoring of treatment response of NPC.

Methods

Here, we present a novel molecular diagnostic technique termed EBV-MCDA-LFB, which integrates multiple cross displacement amplification (MCDA) with nanoparticle-based lateral flow (LFB) to enable simple, rapid and specific detection of EBV. In the EBV-MCDA-LFB system, a set of 10 primers was designed for rapidly amplifying the highly conserved tandem repeat BamHI-W region of the EBV genome. Subsequently, the LFB facilitate direct assay reading, eliminating the use of extra instruments and reagents.

Results

The outcomes showed that the 65°C within 40 minutes was the optimal reaction setting for the EBV-MCDA system. The sensitivity of EBV-MCDA-LFB assay reached 7 copies per reaction when using EBV recombinant plasmid, and it showed 100% specificity without any cross-reactivity with other pathogens. The feasibility of the EBV-MCDA-LFB method for EBV detection was successfully validated by 49 clinical plasma samples. The complete detection process, consisting of rapid template extraction (15 minutes), MCDA reaction (65°C for 40 minutes), and LFB result reading (2 minutes), can be finalized within a 60-minutes duration.

Discussion

EBV-MCDA-LFB assay designed here is a fast, extremely sensitive and specific technique for detecting EBV in field and at the point-of-care (PoC), which is especially beneficial for countries and regions with a high prevalence of the disease and limited economic resources.

A Distinct Anti-EBV DNase Profile in Patients with Undifferentiated Nasopharyngeal Carcinoma Compared to Classical Antigens

Nasopharyngeal cancer (NPC) is a prevalent type of cancer that often takes the form of undifferentiated carcinoma in the Maghreb region. It affects people of all ages. NPC diagnosis, mainly based on detecting Epstein-Barr virus (EBV), has not been well evaluated in North Africa. We compared the classical EBV serological tests using indirect immunofluorescence to the detection of EBV DNase antibodies by immunoblot in Algerian NPC patients. Significant variations were observed among different age groups of patients regarding the presence of VCA-IgA antibodies (0-14 and ≥30 years old, p < 0.0001; 15-19 and ≥30 years old, p < 0.01) and EA-IgA (0-14 and ≥30 years old, p < 0.01; 15-29 and ≥30 years old, p < 0.05). Differences were also noted in the titers of IgA anti-VCA and anti-EA antibodies across the three age groups. Some patients under the age of 30 with detectable IgG anti-VCA antibodies had undetectable IgA anti-VCA antibodies. These patients had a strong anti-DNase IgA response. However, older individuals had a higher level of anti-DNase IgG. Before treatment, children had strong DNase reactivity as indicated by specific IgA antibodies. Young adults had high IgA anti-DNase response, but the elderly (90.9%) had a lower response for these antibodies. Following therapy, the children retained high levels of IgA anti-DNase antibodies, and 66% of the young adults demonstrated robust antibody reactivity against DNase. In contrast, IgG responses to anti-DNase were low in children. This study demonstrated the utility of anti-DNase responses in the diagnosis and prognosis of NPC.

Epstein Barr virus infection in tree shrews alters the composition of gut microbiota and metabolome profile

BACKGROUND

Epstein-Barr virus (EBV) infection is a major global threat; its manifestations range from the absence of symptoms to multiorgan malignancies and various gastrointestinal diseases. Analyzing the composition and metabolomic profile of gut microbiota during acute EBV infection might be instrumental in understanding and controlling EBV.

METHODS

Six tree shrews were inoculated with EBV by intravenous injection. Blood was collected at regular intervals thereafter from the femoral vein to detect EBV and inflammatory biomarker. At the same time, tree shrew faeces were collected for 16 S rRNA gene sequencing and Non-targeted metabolomics analysis.

RESULTS

16 S rRNA gene characterization along with β diversity analysis exhibited remarkable alterations in gut microflora structure with a peak at 7 days post-infection(dpi). Some alterations in the relative richness of bacterial taxon were linked to infectious indicators. Of note, Butyricicoccus relative richness was positively linked to EBV presence in the blood and plasma, the opposite correlation was seen with Variovorax and Paramuribaculum. Non-targeted metabolomics indicated the fecal metabolome profile altered during EBV infection, particularly 7 dpi. The relative abundance of geranic acid and undecylenic acid in stool samples was positively linked to systemic inflammatory biomarkers, and an inverse relationship was reported with the estrone glucuronide, linoleic acid, protoporphyrin IX and tyramine.

CONCLUSION

Collectively, EBV infection in this model correlated with changes in the composition and metabolome profile of the gut microbiota.

Identification of key genes and the pathophysiology associated with allergen-specific immunotherapy for allergic rhinitis

BACKGROUND

Allergen-specific immunotherapy (AIT) is a causative treatment in allergic rhinitis (AR), comprising long-term allergen administration and over three years of treatment. This study is carried out for revealing the mechanisms and key genes of AIT in AR.

METHODS

The present study utilized online Gene Expression Omnibus (GEO) microarray expression profiling dataset GSE37157 and GSE29521 to analyze the hub genes changes related to AIT in AR. Based on limma package, differential expression analysis for the two groups (samples of allergic patients prior to AIT and samples of allergic patients undergoing AIT) was performed to obtain differentially expressed genes (DEGs). Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of DEGs were conducted using DAVID database. A Protein-Protein Interaction network (PPI) was built and a significant network module was acquired by using Cytoscape software (Cytoscape, 3.7.2). Utilizing the miRWalk database, we identified potential gene biomarkers, constructed interaction networks of target genes and microRNAs (miRNAs) using Cytoscape software, and explore the cell type-specific expression patterns of these genes in peripheral blood using publicly available single-cell RNA sequencing data (GSE200107). Finally, we are using PCR to detect changes in the hub genes that are screened using the above method in peripheral blood before and after AIT treatment.

RESULTS

GSE37157 and GSE29521 included 28 and 13 samples, respectively. A total of 119 significantly co-upregulated DEGs and 33 co-downregulated DEGs were obtained from two datasets. The GO and KEGG analyses demonstrated that protein transport, positive regulation of apoptotic process, Natural killer cell mediated cytotoxicity, T cell receptor signaling pathway, TNF signaling pathway, B cell receptor signaling pathway and Apoptosis may be potential candidate therapeutic targets for AIT of AR. From the PPI network, 20 hub genes were obtained. Among them, the PPI sub-networks of CASP3, FOXO3, PIK3R1, PIK3R3, ATF4, and POLD3 screened out from our study have been identified as reliable predictors of AIT in AR, especially the PIK3R1.

CONCLUSION

Our analysis has identified novel gene signatures, thereby contributing to a more comprehensive understanding of the molecular mechanisms underlying AIT in the treatment of AR.

Diagnosis and monitoring of virus-associated cancer using cell-free DNA

Viral-associated cancers are a distinct group of malignancies with a unique pathogenesis and epidemiology. Liquid biopsy is a minimally invasive way to identify tumor-associated abnormalities in blood derivatives, such as plasma, to guide the diagnosis, prognosis, and treatment of patients with cancer. Liquid biopsy encompasses a multitude of circulating analytes with the most extensively studied being cell-free DNA (cfDNA). In recent decades, substantial advances have been made toward the study of circulating tumor DNA in nonviral-associated cancers. Many of these observations have been translated to the clinic to improve the outcomes of patients with cancer. The study of cfDNA in viral-associated cancers is rapidly evolving and reveals tremendous potential for clinical applications. This review provides an overview of the pathogenesis of viral-associated malignancies, the current state of cfDNA analysis in oncology, the current state of cfDNA analysis in viral-associated cancers, and perspectives for the future of liquid biopsies in viral-associated cancers.

Significance of Dynamic Changes of VCA-IgA Levels in Pre- and Post-treatment Plasma of Patients with Nasopharyngeal Carcinoma: Development of a Clinically-Oriented Model

INTRODUCTION

Nasopharyngeal carcinoma (NPC) responds well to radiotherapy but recurrence and metastasis are common. Currently, there is no widely used biomarker for accurately predicting the recurrence and metastasis of NPC. In this study, we aimed to evaluate the prognostic ability of Epstein-Barr virus (EBV) capsid antigen (VCA-IgA) kinetics by assessing the dynamic changes of VCA-IgA levels in the pre- and post-treatment plasma of patients with NPC and have proposed a prognostic model for clinical use.

METHODS

The clinical records of patients with NPC diagnosed at Sun Yat-sen University Cancer Center were retrieved and classified into a respondent (n = 83) or non-respondent (n = 25) cohort based on their response to antitumor therapy. Factors associated with the outcomes of the patients were assessed and incorporated in a nomogram. For internal validation, bootstrapping with 1000 resamples was used. The prediction accuracy and discriminative ability of the nomogram were investigated by calibration and concordance index (C-index) and plotted decision curves to assess the benefits of nomogram-assisted decisions in a clinical context.

RESULTS

Plasma VCA-IgA level of the non-respondent cohort at the 6th month after treatment was found significantly higher than the respondent cohort. Post-treatment VCA-IgA level, smoking, and distant metastases were identified as independent risk factors for disease-free survival (DFS), and were used to stratify patients with NPC into three risk groups. The median DFS of the low-, middle- and high-risk groups were 48.5, 35.0, and 15.5 months, respectively. The C-index of the nomogram was 0.848 (95% CI 0.769-0.926), demonstrating good clinical accuracy for predicting the DFS of patients with NPC. The decision curve showed that the nomogram in predicting DFS was better than VCA-IgA level, smoking, and distant metastases.

CONCLUSION

The proposed VCA-IgA-based nomogram demonstrated a promising ability to predict the DFS of patients with NPC after antitumor therapy. It could be used as a clinical guidance to improve the therapeutic/surveillance strategies of these patients.

Clinical relevance of plasma EBV DNA as a biomarker for nasopharyngeal carcinoma in non-endemic areas: A multicenter study in southwestern China

BACKGROUND

Numerous clinical studies have validated plasma EBV DNA as a reliable biomarker for nasopharyngeal carcinoma (NPC) screening, tumor load monitoring, and prognosis prediction in endemic regions. However, the clinical relevance of plasma EBV DNA as a biomarker for NPC in non-endemic areas is still unclear.

METHOD

The pretreatment plasma EBV DNA of 1405 newly diagnosed NPC patients from three major regional hospitals in non-endemic areas were analyzed retrospectively. The medical records of 244 age- and gender-matched healthy individuals were reviewed. EBV DNA was detected using Polymerase Chain Reaction (PCR). Based on the baseline of 400 and 0 copies/mL, the distribution characteristics of the pretreatment EBV DNA load in different clinical stages and geographic regions were analyzed. The diagnostic value of pretreatment plasma EBV DNA for NPC with two baselines was evaluated using the ROC curve.

RESULTS

NPC patients had a significantly higher pretreatment EBV DNA level than healthy controls (P＜0.001). Pretreatment EBV DNA was closely associated with clinical and TNM stages in non-endemic areas, as it was in endemic areas. However, when 400 copies/mL set as the detection baseline, the sensitivity and specificity for NPC diagnosis were 40.8 % and 100 %, respectively (AUC = 0.704, cut off = 200.5 copies/mL). This sensitivity was lower than that reported in endemic regions (41.5 % - 97.1 %). Lower sensitivity may result in false negatives, missing diagnoses during NPC screening. Further investigation revealed that 39.7 % (558/1405) of NPC patients had detectable EBV DNA and S amplification curves. Optimizing the detection limit to 0 copies/mL, the sensitivity could be improved to 80.5 % (AUC = 0.901).

CONCLUSIONS

In non-endemic areas, the clinical significance of plasma EBV DNA as a biomarker for NPC was restricted due to the low detection limit of 400 copies/mL. More efficient nucleic acid extraction and detection methods are needed to optimize the detection limit and increase the clinical application of plasma EBV DNA for NPC.

Nasopharyngeal Carcinoma Burden and Its Attributable Risk Factors in China: Estimates and Forecasts from 1990 to 2050

Nasopharyngeal carcinoma (NPC) is an uncommon and aggressive malignant head and neck cancer, which is highly prevalent in southern and southwestern provinces in China. The aim of this study was to examine the disease burden and risk factors of nasopharyngeal carcinoma in China from 1990 to 2019 and to predict the incidence trends from 2020 to 2049. All data were extracted from the 2019 Global Burden of Disease (GBD) study. Joinpoint regression and age-period-cohort (APC) models were chosen to analyze prevalence trends. The temporal trends and age distribution of risk factors were also analyzed descriptively. Bayesian APC models were used to predict the prevalence from 2020 to 2049. The results indicate a higher disease burden in men and older adults. Their attributable risk factors are smoking, occupational exposure to formaldehyde, and alcohol use. We predict that the incidence will be on the rise in all age groups between 2020 and 2049, with the highest incidence in people aged 70 to 89 years. In 2049, the incidence rate is expected to reach 13.39 per 100,000 (50-54 years), 16.43 (55-59 years), 17.26 (60-64 years), 18.02 (65-69 years), 18.55 (70-74 years), 18.39 (75-79 years), 19.95 (80-84 years), 23.07 (85-89 years), 13.70 (90-94 years), and 6.68 (95+ years). The findings of this study might deserve consideration in China's NPC prevention and control policy design.

Treatment Protocols in the Efficacy and Safety of Anti-EGFR Medicines in Combination with Standard Therapy for Patients with Nasopharyngeal Cancer: A Meta-Analysis

Objective

This study was conducted to compare the efficacy of standard therapy (radiotherapy/RT/CT) with that of antiepidermal growth factor receptor (anti-EGFR) monoclonal antibody (NPC) therapy in patients with advanced nasopharyngeal cancer.

Methods

A meta-analysis was performed to meet the objective of this study. The English databases PubMed, Cochrane Library, and Web of Science were searched. The literature review compared anti-EGFR-targeted therapy with conventional therapy practices. The main outcome measure was overall survival (OS). Secondary goals were progression-free survival (PFS), locoregional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS), and adverse events (grade 3).

Results

The database search resulted in 11 studies, with a total of 4219 participants. It was found that combining an anti-EGFR regimen with conventional therapy did not enhance OS (hazard ratio [HR] = 1.18; 95%confidence interval [CI] = 0.51-2.40; p = 0.70) or PFS appreciably (HR = 0.95; 95%CI = 0.51-1.48; p = 0.88) in patients with nasopharyngeal carcinoma. While LRRFS increased considerably (HR = 0.70; 95%CI = 0.67-1.00; p = 0.01), the combined regimen did not improve DMFS (HR = 0.86; 95%CI = 0.61-1.12; p = 0.36). Treatment-related adverse events included haematological toxicity (RR = 0.2; 95%CI = 0.08-0.45; p = 0.01), cutaneous reactions (RR = 7.05; 95%CI = 2.15-23.09; p = 0.01), and mucositis (RR = 1.96; 95%CI = 1.58-2.09; p = 0.01).

Conclusions

Individuals who have nasopharyngeal cancer do not have an increased chance of surviving until a local recurrence of their disease if they get normal therapy in addition to an anti-EGFR regimen. However, this combination does not enhance overall survival. On the other hand, this factor adds to an increase in the number of adverse effects.

Nasopharyngeal carcinoma in a non-endemic country-Validation of the new NPC staging system

BACKGROUND

Nasopharyngeal carcinoma (NPC) staging has recently been updated, with the eighth edition of the AJCC/UICC. In the last ten years, Intensity Modulated Radiotherapy (IMRT) has become a standard treatment for NPC. The authors aim to assess the benefits of the new AJCC staging system in predicting prognosis, as well as the improvement in survival outcomes in the IMRT era, in non-edemic population.

METHODS

Retrospective study selecting patients treated for NPC between January 2009 and December 2019 in a cancer treatment center in Portugal. Initial TNM staging (according to the seventh edition of the AJCC/UICC) was collected and each patient was restaged according to the new TNM staging system. Overall survival (OS) and Distant Metastasis Free Survival (DMFS) stratified by T and N classification and stage (according to the both TNM staging systems) were analyzed. Univariate and multivariate analysis was performed to evaluate which factors influence OS and DMFS. Data in this series was compared with a previous report from the same institution, before IMRT standard use.

RESULTS

113 patients were included, averaging 53.74 (±1.4) years old. With the new TNM staging, 5 patients were downstaged and 3 patients were upstaged. Over a median follow-up time of 41 months, the 5-year OS and DMFS were 77% and 79.8%, respectively. Neither the seventh nor the eighth editions of the AJCC/UICC staging system had good overall discrimination between each T classification OS and DMFS curves. Both the seventh and the eighth editions of the AJCC/UICC staging system had statistically significant overall discrimination between each N group and each stage group classification OS curves. Only N classification predicted OS in multivariate analysis. When comparing to a previous report from the same institution, OS has not improved majorly, especially in locoregionally advanced disease.

CONCLUSIONS

TNM staging still presents limitations in adequately predicting OS and DMFS.

Comparing BamHI-W and CE-marked assays to detect circulating Epstein-Barr Virus (EBV) DNA of nasopharyngeal cancer patients in a non-endemic area

OBJECTIVES

Plasma Epstein-Barr Virus (EBV)-DNA is a well-established prognostic biomarker in nasopharyngeal carcinoma (NPC). Different methods for assessment include single-copy gene targeted, European Conformity (CE)-marked assays, which are mostly employed in non-endemic settings, vs multiple-copy gene targeted, in-house BamHI-W based assays, which currently represent the most widely used method for EBV-DNA quantification. To date, evidence concerning the commutability of these different assays is still limited.

MATERIALS AND METHODS

From August 2016 to March 2018, 124 plasma and 124 whole blood (WB) samples from 93 NPC patients were collected at different time-points for each patient. EBV-DNA viral load was quantified in pre- (n = 12) and post-treatment (n = 9), follow-up (n = 53), and recurrent/metastatic (R/M) (n = 50) phase. For each sample, one in-house BamHI-W vs three different CE-marked plasma assays were compared; the performance of plasma vs WB matrix was also assessed. Quantitative agreement of EBV-DNA values was evaluated by linear correlation and Bland-Altman analysis.

RESULTS

A statistically significant (p = 0.0001) agreement between all CE-marked and the BamHI-W assays was found using plasma matrix, regardless of clinical phase. The results obtained in copies/ml were comparable to those expressed in IU/ml. When using WB matrix, the number of positive detections increased in the post-treatment phase.

CONCLUSIONS

Our retrospective comparison supported an agreement between Plasma BamHI-W and CE-marked assays in measuring EBV-DNA for non-endemic NPC patients. There were no significant interferences from different measurement units (IU/ml vs copies/ml). Further evaluations are needed to better clarify the role of WB.

Epstein-Barr Virus-Encoded MicroRNA-BART18-3p Promotes Colorectal Cancer Progression by Targeting De Novo Lipogenesis

The Epstein-Barr virus (EBV) genome encodes a cluster of 22 viral microRNAs, called miR-BamHI-A rightward transcripts (miR-BARTs), which are shown to promote the development of cancer. Here, this study reports that EBV-miR-BART18-3p is highly expressed in colorectal cancer (CRC) and is closely associated with the pathological and advanced clinical stages of CRC. Ectopic expression of EBV-miR-BART18-3p leads to increased migration and invasion capacities of CRC cells in vitro and causes tumor metastasis in vivo. Mechanistically, EBV-miR-BART18-3p activates the hypoxia inducible factor 1 subunit alpha/lactate dehydrogenase A axis by targeting Sirtuin, which promotes lactate accumulation and acetyl-CoA production in CRC cells under hypoxic condition. Increased acetyl-CoA utilization subsequently leads to histone acetylation of fatty acid synthase and fatty acid synthase-dependent fat synthesis, which in turn drives de novo lipogenesis. The oncogenic role of EBV-miR-BART18-3p is confirmed in the patient-derived tumor xenograft mouse model. Altogether, the findings define a novel mechanism of EBV-miR-BART18-3p in CRC development through the lipogenesis pathway and provide a potential clinical intervention target for CRC.

Pathogenesis and Diagnostic Significance of EBV-miR-BARTs in Nasopharyngeal Carcinoma

Objective. Examining the role of EBV-miR-BARTs in nasopharyngeal cancer etiology and diagnosis. Method. As the subjects of this study, nasopharyngeal cancer cell lines were chosen and then randomly assigned to one of four groups: the control group, EBV-miR-BART5-3p NC, EBV-miR-BART5-3p mimics, and EBV-miR-BART5-3p inhibitor groups. Utilizing reverse transcription polymerase chain reaction, we determined the levels of gene expression in nasopharyngeal cancer cells that had been treated with EBV-miR-BART5-3p (RT-PCR). The MTT, Transwell, and scratch tests were used to determine the degree to which cells underwent apoptosis, invasion, and migration. The Western blotting method was used in order to examine the protein expression. Result. Compared with normal nasopharyngeal cells, $P0.05$ showed that nasopharyngeal cancer cells had greater EBV-miR-BART5-3p expressions and proliferation rates in the control, EBV-miR-BART5-3p NC, and EBV-miR-BART5-3p No statistically significant differences were seen between the mimic groups ( $P>0.05$ ); compared with the control group, the proliferation rate of the EBV-miR-BART5-3p inhibitor group was lower with $P<0.05$ . At a significance threshold of $P0.05$ , there was no difference in the rates of apoptosis between the control group and the EBV-miR- BART5-3p NC group. Comparing the control group to the EBV-miR-BART5-3p mimics group and the EBV-miR-BART5-3p inhibitors group revealed that the rate of apoptosis was dramatically enhanced in the EBV-miR-BART5-3p inhibitors group but significantly decreased in the control group ( $P0.05$ ). When comparing the control group to the EBV-miR-BART5-3p NC group, there was no statistically significant change in the total number of invasive cells ( $P>0.05$ ). When comparing the EBV-miR-BART5-3p mimics group to the control group, we found a statistically significant increase in the former and a decrease in the latter ( $P0.05$ ). The migration rates of the control group, the EBV-miR-BART5-3p NC group, and the EBV-miR-BART5-3p mimics group did not vary from one another in a way that was statistically significant ( $P>0.05$ ). When compared to the control group, the migration rate was considerably (P 0.05) lower in the EBV-miR-BART5-3p inhibitor group. There were no discernible changes identified ( $P>0.05$ ) in the levels of Bcl-2 protein expression in the control group, the EBV-miR-BART5-3p NC group, and the EBV-miR-BART5-3p mimic group in a research that compared these three groups. Protein levels of BCL-2 were significantly decreased ( $P0.05$ ) in the EBV-miR-BART5-3p inhibitor group, in comparison to the control group. When comparing the control and EBV- miR-BART5-3p NC groups, we found no statistically significant differences in Bax and Caspase-3 protein expression levels ( $P>0.05$ ). The protein expressions of Bax and Caspase-3 were statistically significantly greater in the EBV-miR-BART5-3p contrast between the inhibitor and control groups. When comparing the protein expressions of MMP-2 and MMP-9 between the control group, the EBV-miR-BART5-3p NC group, and the EBV-miR-BART5-3p mimics group, there was no statistically significant change ( $P>0.05$ ). Protein levels of MMP-2 and MMP-9 were inhibited by EBV-miR-BART5-3p to a greater extent ( $P0.05$ ) in the experimental group compared to the control group. Conclusion. The understanding that inhibiting expression of EBV-miR-BART5-3p might reduce the risk of developing nasopharyngeal cancer may help direct clinical treatment for the condition.

Advanced Nasopharyngeal Carcinoma: Current and Emerging Treatment Options

Nasopharyngeal carcinoma (NPC) has seen improved treatment outcomes and a decrease in incidence worldwide in recent years due to developments in medicine and improved public health. However, 70% of cases are still diagnosed at advanced stages and these advanced NPC cases show a poor prognosis. Reports on current and future treatment in advanced NPC are summarized. Chemoradiotherapy is the mainstay of treatment for advanced NPC. The administration of platinum agents as a concurrent drug and intensity modulated radiotherapy (IMRT) is the most appropriate irradiation method, and is associated with high local control rates. For induction and adjuvant chemotherapy, platinum-based two- or three-drug combination chemotherapy is recommended. The tumour volume, plasma Epstein-Barr virus (EBV)-DNA levels, and the tumour site are used to determine the indication for adjuvant and neo-adjuvant chemotherapy. The tolerability of induction chemotherapy is controversial, and the indications and timing should be carefully considered in each case. Chemotherapy is used for patients with distant metastasis. Gemcitabine/cisplatin is the first-line regimen. The efficacy of immune checkpoint inhibitor (ICI) treatment has recently been reported for NPC and, as in other areas of the head and neck, it is expected to be effective for patients with recurrent/distant metastasis. Trials are underway for various uses of ICIs, including induction chemotherapy, postoperative treatment, and use in combination with chemoradiotherapy. Immunotherapy for NPC, an EBV-associated cancer, has been reported to have some efficacy with immunotherapy used in other EBV-associated cancers. Immunotherapy may be introduced for NPC in the future, depending on the results of clinical trials. Future changes in the treatment of NPC are expected to include risk classification based on plasma EBV-DNA levels and the development of personalized treatment with individual selection of timing and type of therapy.

MicroRNA-613 Enhances Nasopharyngeal Carcinoma Cell Radiosensitivity via the DNA Methyltransferase 3B/Tissue Inhibitor of Matrix Metalloproteinase-3/Signal Transducer and Activator of Transcription-1/Forkhead Box O-1 Axis

Nasopharyngeal carcinoma (NPC) is a common malignancy of the nasopharynx, and radioresistant represents the main obstacle in NPC treatment. Malignant transformation of normal cells is driven by genetic and epigenetic changes, which are primarily manifested as changes in miRNA levels and DNA methylation status. microRNA (miR)-613 plays an inhibitory role in several types of cancer. Herein, the current study sought to explore the roles of miR-613 in NPC cell radiosensitivity. miR-613 expression patterns in NPC tissues were detected, and its correlation with clinical indexes was analyzed. NP-69 and C666-1 cell lines were selected for cellular experimentation. Radioresistant cell line C666-1R was obtained by fractionated radiation. Cell viability, survival fraction, and apoptosis were detected by CCK-8, colony formation assay, and flow cytometry. The binding relation between miR-613 and DNMT3B was verified by dual-luciferase and RIP assays. miR-613 was lowly expressed in NPC tissues and cells, with lower expression levels in C666-1R than C666-1, and further correlated with lymph node metastasis, tumor size, and tumor metastasis. miR-613 overexpression reduced C666-1R cell viability and survival fraction and increased apoptosis, while C666-1 cells with silencing miR-613 presented the opposite trends. miR-613 targeted DNMT3B. miR-613 and DNMT3B overexpression led to enhanced C666-1R cell viability and survival fraction and decreased apoptosis. miR-613 reduced TIMP3 methylation and elevated TIMP3 protein level by inhibiting DNMT3B. miR-613 enhanced NPC radiosensitivity by inhibiting the DNMT3B/TIMP3/STAT1/FOXO1 pathway. Collectively, miR-613 inhibited DNMT3B, reduced TIMP3 methylation, and increased TIMP3 protein level, thus inhibiting the STAT1/FOXO1 pathway and enhancing the radiosensitivity of NPC cells.

Clinical Characteristics and Predictive Outcomes of Recurrent Nasopharyngeal Carcinoma-A Lingering Pitfall of the Long Latency

Purpose: To investigate the clinical characteristics, risk factors, and clinical outcomes of long-latent recurrence (>five years) of nasopharyngeal carcinoma (NPC). Methods: This retrospective study enrolled newly diagnosed NPC patients from the Chang Gung Research Database between January 2007 and December 2019. We analyzed the patients’ characteristics and survival outcomes after recurrence. Results: A total of 2599 NPC patients were enrolled. The overall recurrence rate was 20.5%, while 8.1% of patients had long-latent recurrence (>five years). These patients had a higher percentage of initial AJCC (The American Joint Committee on Cancer) stage I/II (60.5%, p = 0.001) and local recurrence (46.5%, p < 0.001). Unresectable rT3 and rT4 were found in 60% of patients when recurrence and 30% of local recurrence occurred in the skull base, which could not be detected by the regular endoscopy. The five-year overall survival rate of long-latent recurrence was 19.7%. Alive patients tended to be asymptomatic but have regular follow-ups with the interval less than six months. Multivariate analysis showed age and initial advanced AJCC stages were independent risk factors of death after recurrence. In contrast, patients with recurrence between two and five years, salvage surgeries, and regional recurrence had favorable survival outcomes. Conclusion: Long-latent NPC recurrence is not rare, and the survival outcome is poor. Regular follow-up for early detection of NPC recurrence is necessary even after five years of disease-free period.

Noninvasive Diagnosis of Nasopharyngeal Carcinoma Based on Phenotypic Profiling of Viral and Tumor Markers on Plasma Extracellular Vesicles

Nasopharyngeal carcinoma (NPC) is a malignant tumor commonly associated with Epstein-Barr virus (EBV) infection, and its early diagnosis as well as its differentiation from nasopharyngitis (NPG) remains challenging due to the insufficient sensitivity of routine screening methods in clinical practice. To date, circulating extracellular vesicles (EVs, 40-1000 nm) have shown appealing potential in liquid biopsy for cancer diagnosis and prognosis. Herein, nanoflow cytometry (nFCM) capable of single EV analysis was applied to examine the expression of surface proteins with very low copy numbers on individual EVs as small as 40 nm. The particle concentrations of five EV subsets exposing EBV-encoded latent membrane proteins (LMP1 and LMP2A) and tumor markers (PD-L1, EGFR, and EpCAM) in plasma were determined rapidly via single-particle enumeration. We identified a five-marker panel named EV^SUM5 (an unweighted sum of the concentration of the five individual EV subsets) that significantly surpassed the traditional VCA-IgA assay in discriminating NPC patients from both healthy donors and NPG patients with accuracies of 96.3 and 83.1%, respectively. Moreover, EV^SUM2 (an unweighted sum of virus-specific LMP1- and LMP2A-positive EVs) could achieve the diagnosis of NPG with an accuracy of 82.6%. Collectively, the work presented a rapid, reliable, and noninvasive method as well as two diagnostic markers to help more accurately differentiate NPC from NPG patients and healthy donors in clinical practice.

METTL3-mediated m6A modification promotes processing and maturation of pri-miRNA-19a to facilitate nasopharyngeal carcinoma cell proliferation and invasion

The interplay between N6-methyladenosine (m6A) modification and microRNAs (miRs) participates in cancer progression. This study is conducted to explore the role of miR-19a-3p in nasopharyngeal carcinoma (NPC) cell proliferation and invasion. RT-qPCR and western blot showed that miR-19a-3p was upregulated in NPC tissues and cells and related to poor prognosis, methyltransferase-like 3 (METTL3) was highly expressed while BMP and activin membrane-bound inhibitor (BAMBI) was weakly expressed in NPC tissues and cells. miR-19a-3p downregulation inhibited cell proliferation and invasion while miR-19a-3p overexpression played an opposite role. m6A quantification and m6A RNA immunoprecipitation assays showed that METTL3-mediated m6A modification promoted the processing and maturation of pri-miR-19a via DGCR8. Dual-luciferase assay showed that BAMBI was a target of miR-19a-3p. The rescue experiments showed that BAMBI downregulation reversed the role of miR-19a-3p inhibition in NPC cells. A xenograft tumor model showed that METTL3 downregulation inhibited tumor growth via the miR-19a-3p/BAMBI in vivo. Overall, our findings elicited that METTL3-mediated m6A modification facilitated the processing and maturation of pri-miR-19a via DGCR8 to upregulate miR-19a-3p, and miR-19a-3p inhibited BAMBI expression to promote NPC cell proliferation and invasion, thus driving NPC progression.

Circulating microRNAs as the Potential Diagnostic and Prognostic Biomarkers for Nasopharyngeal Carcinoma

microRNAs are endogenous non-coding miRNAs, 19–25 nucleotides in length, that can be detected in the extracellular environment in stable forms, named circulating miRNAs (CIR-miRNAs). Since the first discovery of CIR-miRNAs, a large number of studies have demonstrated that the abnormal changes in its expression could be used to significantly distinguish nasopharyngeal carcinoma (NPC) from healthy cells. We herein reviewed and highlighted recent advances in the study of CIR-miRNAs in NPC, which pointed out the main components serving as promising and effective biomarkers for NPC diagnosis and prognosis. Furthermore, brief descriptions of its origin and unique characteristics are provided.

The implications of cell-free DNAs derived from tumor viruses as biomarkers of associated cancers

Cancer is still ranked as a leading cause of death according to estimates from the World Health Organization (WHO) and the strong link between tumor viruses and human cancers have been proved for almost six decades. Cell-free DNA (cfDNA) has drawn enormous attention for its dynamic, instant, and noninvasive advantages as one popular type of cancer biomarker. cfDNAs are mainly released from apoptotic cells and exosomes released from cancer cells, including those infected with viruses. Although cfDNAs are present at low concentrations in peripheral blood, they can reflect tumor load with high sensitivity. Considering the relevance of the tumor viruses to the associated cancers, cfDNAs derived from viruses may serve as good biomarkers for the early screening, diagnosis, and treatment monitoring. In this review, we summarize the methods and newly developed analytic techniques for the detection of cfDNAs from different body fluids, and discuss the implications of cfDNAs derived from different tumor viruses in the detection and treatment monitoring of virus-associated cancers. A better understanding of cfDNAs derived from tumor viruses may help formulate novel anti-tumoral strategies to decrease the burden of cancers that attributed to viruses. This article is protected by copyright. All rights reserved.

Nomogram Based on Inflammatory Biomarkers and Nutritional Indicators for Predicting Overall Survival in Locoregionally Advanced Nasopharyngeal Carcinoma

Purpose

To establish and validate a nomogram to predict overall survival in locoregionally advanced nasopharyngeal carcinoma (LA-NPC) based on inflammatory biomarkers and nutritional indicators.

Patients and Methods

A total of 1304 patients who underwent concurrent chemoradiotherapy (CCRT) with or without induction chemotherapy (IC) or adjuvant chemotherapy (AC) were included in the study. The prognosis factors of overall survival (OS) were selected by Cox regression analysis to establish the nomogram. Concordance index (C-index), calibration curves, decision curve analysis (DCA) and Kaplan-Meier curves were used to evaluate the nomogram.

Results

Using multivariate Cox analysis of clinically important variables, the following variables were incorporated in the prediction of OS: age, gender, T stage, N stage, pre-treatment plasma Epstein-Barr virus (EBV) DNA, neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), lactic dehydrogenase-to-albumin ratio (LAR) and prognostic nutritional index (PNI). The discriminative ability, clinical usefulness and calibration of the nomogram revealed good predictive ability as indicated by the C-index (0.717 in nomogram and 0.602 in the 8th AJCC staging system), decision curves, calibration curves and K-M curves.

Conclusion

Inflammatory biomarkers and nutritional indicators of survival for LA-NPC were selected to create a nomogram predicting OS. The proposed nomogram resulted in more accurate prognostic prediction than 8th AJCC staging system.

Noncoding RNAs and their therapeutics in paclitaxel chemotherapy: Mechanisms of initiation, progression, and drug sensitivity

The identification of agents that can reverse drug resistance in cancer chemotherapy, and enhance the overall efficacy is of great interest. Paclitaxel (PTX) belongs to taxane family that exerts an antitumor effect by stabilizing microtubules and inhibiting cell cycle progression. However, PTX resistance often develops in tumors due to the overexpression of drug transporters and tumor-promoting pathways. Noncoding RNAs (ncRNAs) are modulators of many processes in cancer cells, such as apoptosis, migration, differentiation, and angiogenesis. In the present study, we summarize the effects of ncRNAs on PTX chemotherapy. MicroRNAs (miRNAs) can have opposite effects on PTX resistance (stimulation or inhibition) via influencing YES1, SK2, MRP1, and STAT3. Moreover, miRNAs modulate the growth and migration rates of tumor cells in regulating PTX efficacy. PIWI-interacting RNAs, small interfering RNAs, and short-hairpin RNAs are other members of ncRNAs regulating PTX sensitivity of cancer cells. Long noncoding RNAs (LncRNAs) are similar to miRNAs and can modulate PTX resistance/sensitivity by their influence on miRNAs and drug efflux transport. The cytotoxicity of PTX against tumor cells can also be affected by circular RNAs (circRNAs) and limitation is that oncogenic circRNAs have been emphasized and experiments should also focus on onco-suppressor circRNAs.

Salidroside suppresses the activation of nasopharyngeal carcinoma cells via targeting miR-4262/GRP78 axis

To study the effect of Salidroside on nasopharyngeal carcinoma (NPC) cells and its mechanism. NPC cells were cultured, MTT was used to detect the effect of Salidroside on cell proliferation, apoptosis detected by flow cytometry assay, Western blot was used to detect the related protein expression. MiR-4262 and GRP78 used qRT-PCR for evaluation. Mimics/mimic NC and miR-4262 inhibitor/inhibitor NC were transfected into CNE2 and HONE1 cell lines, and cell viability was detected by MTT. Caspase-3, −8 and −9 activities were detected by caspase colorimetric assay kit. Targetscan predicted that downstream target of miR-4262. Relative luciferase activity was detected by luciferase assay. The effect of Salidroside on the growth of transplanted tumor in nude mice was observed. After Salidroside treatment, cell proliferation decreased and apoptosis increased, Bax protein expression increased and Bcl-2 decreased; miR-4262 expression level in nasopharyngeal carcinoma tissues was lower than that in adjacent tissues. GRP78 was the target of miR-4262 and downregulate the expression of miR-4262 in NPC cells can increase the expression of GRP78, and the expression of GRP78 decreased after upregulating the expression of miR-4262. Salidroside could inhibit the growth of NPC xenografts in nude mice. The level of Bax was increased and Bcl-2 was decreased in Salidroside group. Salidroside can significantly inhibit the proliferation and promote the apoptosis of NPC cells via regulating miR-4262/GRP78 signal axis.

Application of liquid biopsy as multi-functional biomarkers in head and neck cancer

Head and neck squamous cell carcinoma (HNSCC) is a molecularly heterogeneous disease, with a 5-year survival rate that still hovers at ~60% despite recent advancements. The advanced stage upon diagnosis, limited success with effective targeted therapy and lack of reliable biomarkers are among the key factors underlying the marginally improved survival rates over the decades. Prevention, early detection and biomarker-driven treatment adaptation are crucial for timely interventions and improved clinical outcomes. Liquid biopsy, analysis of tumour-specific biomarkers circulating in bodily fluids, is a rapidly evolving field that may play a striking role in optimising patient care. In recent years, significant progress has been made towards advancing liquid biopsies for non-invasive early cancer detection, prognosis, treatment adaptation, monitoring of residual disease and surveillance of recurrence. While these emerging technologies have immense potential to improve patient survival, numerous methodological and biological limitations must be overcome before their implementation into clinical practice. This review outlines the current state of knowledge on various types of liquid biopsies in HNSCC, and their potential applications for diagnosis, prognosis, grading treatment response and post-treatment surveillance. It also discusses challenges associated with the clinical applicability of liquid biopsies and prospects of the optimised approaches in the management of HNSCC.

Tree Shrew Is a Suitable Animal Model for the Study of Epstein Barr Virus

Epstein-Barr virus (EBV) is a human herpesvirus that latently infects approximately 95% of adults and is associated with a spectrum of human diseases including Infectious Mononucleosis and a variety of malignancies. However, understanding the pathogenesis, vaccines and antiviral drugs for EBV-associated disease has been hampered by the lack of suitable animal models. Tree shrew is a novel laboratory animal with a close phylogenetic relationship to primates, which is a critical advantage for many animal models for human disease, especially viral infections. Herein, we first identified the key residues in the CR2 receptor that bind the gp350 protein and facilitate viral entry. We found that tree shrew shares 100% sequence identity with humans in these residues, which is much higher than rabbits (50%) and rats (25%). In vitro analysis showed that B lymphocytes of tree shrews are susceptible to EBV infection and replication, as well as EBV-enhanced cell proliferation. Moreover, results of in vivo experiments show that EBV infection in tree shrews resembles EBV infection in humans. The infected animals exhibited transient fever and loss of weight accompanied by neutropenia and high viremia levels during the acute phase of the viral infection. Thereafter, tree shrews acted as asymptomatic carriers of the virus in most cases that EBV-related protein could be detected in blood and tissues. However, a resurgence of EBV infection occurred at 49 dpi. Nanopore transcriptomic sequencing of peripheral blood in EBV-infected animals revealed the dynamic changes in biological processes occurring during EBV primary infection. Importantly, we find that neutrophil function was impaired in tree shrew model as well as human Infectious Mononucleosis datasets (GSE85599 and GSE45918). In addition, retrospective case reviews suggested that neutropenia may play an important role in EBV escaping host innate immune response, leading to long-term latent infection. Our findings demonstrated that tree shrew is a suitable animal model to evaluate the mechanisms of EBV infection, and for developing vaccines and therapeutic drugs against EBV.

Advances in pathogenesis and precision medicine for nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a squamous carcinoma with apparent geographical and racial distribution, mostly prevalent in East and Southeast Asia, particularly concentrated in southern China. The epidemiological trend over the past decades has suggested a substantial reduction in the incidence rate and mortality rate due to NPC. These results may reflect changes in lifestyle and environment, and more importantly, a deeper comprehension of the pathogenic mechanism of NPC, leading to much progress in the preventing, screening, and treating for this cancer. Herein, we present the recent advances on the key signal pathways involved in pathogenesis of NPC, the mechanism of Epstein‐Barr virus (EBV) entry into the cell, and the progress of EBV vaccine and screening biomarkers. We will also discuss in depth the development of various therapeutic approaches including radiotherapy, chemotherapy, surgery, targeted therapy, and immunotherapy. These research advancements have led to a new era of precision medicine in NPC.

Long intergenic non-protein coding RNA 02570 promotes nasopharyngeal carcinoma progression by adsorbing microRNA miR-4649-3p thereby upregulating both sterol regulatory element binding protein 1, and fatty acid synthase

Our previous studies have elucidated a possible connection between long intergenic non-protein coding RNA 2570 (LINC02570) and nasopharyngeal carcinoma (NPC). However, the precise mechanism by which LINC02570 promotes NPC remains unknown. We used quantitative polymerase chain reaction (qPCR) to detect LINC02570 expression in nasopharyngeal cell lines, NPC tissues, and chronic rhinitis tissues. Subcellular LINC02570 localization was confirmed by fluorescence in situ hybridization (FISH). The effects of LINC02570 stable knockdown and overexpression on viabillity, proliferation, migration, and invasion were analyzed using 3-(4,5-Dimethyl-2-Thiazolyl)-2,5-Diphenyl-2-H-Tetrazolium bromide (MTT), a colorimetric focus-formation assay, a wound healing assay, and transwell assays. RNA crosstalk analysis in silico predicted microRNA-4649-3p (miR-4649-3p) binding to LINC02570 or sterol regulatory element binding transcription factor 1 (SREBF1). A dual luciferase reporter assay was used to confirm potential interactions. Sterol regulatory element binding protein 1 (SREBP1) and fatty acid synthase (FASN) expression were detected by western blotting. The results suggest that LINC02570 is upregulated in late clinical stage NPC patients, and promotes NPC progression by adsorbing miR-4649-3p to up-regulate SREBP1 and FASN. This study elucidates a potential chemotherapeutic target involved in lipid metabolism in NPC.

MicroRNA and Other Non-Coding RNAs in Epstein-Barr Virus-Associated Cancers

EBV is a direct causative agent in around 1.5% of all cancers. The oncogenic properties of EBV are related to its ability to activate processes needed for cellular proliferation, survival, migration, and immune evasion. The EBV latency program is required for the immortalization of infected B cells and involves the expression of non-coding RNAs (ncRNAs), including viral microRNAs. These ncRNAs have different functions that contribute to virus persistence in the asymptomatic host and to the development of EBV-associated cancers. In this review, we discuss the function and potential clinical utility of EBV microRNAs and other ncRNAs in EBV-associated malignancies. This review is not intended to be comprehensive, but rather to provide examples of the importance of ncRNAs.

Performance of Plasma HSP90α, Serum EBV VCA IgA Antibody and Plasma EBV DNA for the Diagnosis and Prognosis Prediction of Nasopharyngeal Carcinoma

OBJECTIVE

The aim of this study was to evaluate the effectiveness of Epstein-Barr virus (EBV) VCA-IgA antibody, EBV DNA and HSP90α alone or in combinations for the diagnosis and prognostic prediction of nasopharyngeal carcinoma (NPC).

METHODS

A total of 113 treatment-naïve patients with NPC and 40 healthy controls were enrolled. Plasma HSP90α and serum EBV VCA IgA antibody were detected using ELISA, and plasma EBV DNA was quantified using qPCR assay. The effectiveness of plasma HSP90α level, serum EBV VCA IgA antibody and plasma EBV DNA was examined in the diagnosis and prognosis prediction of NPC.

RESULTS

Higher plasma HSP90α, serum EBV VCA IgA antibody and plasma viral load of EBV DNA were detected in NPC patients than in healthy controls (P < 0.001). The plasma HSP90α levels, serum EBV VCA IgA antibody titers and plasma viral load of EBV DNA were significantly greater in NPC patients with stages III and IV than in those with stages I and II (P < 0.001), and significantly lower plasma HSP90α levels, serum EBV VCA IgA antibody titers and plasma viral load of EBV DNA were found in the good prognosis group than in the poor prognosis group post-treatment (P < 0.05). The area under representative operating curves (AUCs) of plasma HSP90α, serum EBV VCA IgA antibody and plasma EBV DNA alone and in combination were 0.884, 0.841, 0.934 and 0.954 for the diagnosis of NPC, respectively. Univariate and multivariate Cox proportional hazards regression analyses identified HSP90α as an independent prognostic factor for NPC.

CONCLUSION

The combination of plasma HSP90α, serum EBV VCA IgA antibody and plasma EBV DNA shows high diagnostic performance for NPC, and plasma HSP90α may be a potential marker for diagnosis and prognosis prediction of NPC.

Current Status and Future Perspectives about Molecular Biomarkers of Nasopharyngeal Carcinoma

Simple Summary

Nasopharyngeal carcinoma is a serious major public health problem in its endemic countries. Up to 80% of NPC patients with locally advanced disease or distant metastasis at diagnosis were associated with poor prognosis and with median survival less than 4 months. The mortality rate of NPC metastasis is up to 91%. To date, there is no available curative treatment or reliable early diagnosis or prognosis for NPC. Discovery and development of reliable early diagnosis and prognosis biomarkers for nasopharyngeal carcinoma are urgent needed. Hence, we have here listed the potential early diagnosis and prognosis biomarker candidates for nasopharyngeal carcinoma. This review will give an insight to readers on the progress of NPC biomarker discovery to date, as well as future prospective biomarker development and their translation to clinical use.

Abstract

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy that shows a remarkable ethnic and geographical distribution. It is one of the major public health problems in some countries, especially Southern China and Southeast Asia, but rare in most Western countries. Multifactorial interactions such as Epstein–Barr virus infection, individual’s genetic susceptibility, as well as environmental and dietary factors may facilitate the pathogenesis of this malignancy. Late presentation and the complex nature of the disease have led it to become a major cause of mortality. Therefore, an effective, sensitive, and specific molecular biomarker is urgently needed for early disease diagnosis, prognosis, and prediction of metastasis and recurrence after treatment. In this review, we discuss the recent research status of potential biomarker discovery and the problems that need to be explored further for better NPC management. By studying the aberrant pattern of these candidate biomarkers that promote NPC development and progression, we are able to understand the complexity of this malignancy better, hence positing our stands better towards strategies that may provide a way forward to the discovery of more reliable and specific biomarkers for diagnosis and targeted therapeutic development.

Impact of smoking on survival in nasopharyngeal carcinoma: A cohort study with 23,325 patients diagnosed from 1990 to 2016

BACKGROUND

We aimed to compare the survival outcomes of patients with nasopharyngeal carcinoma (NPC) who had different smoking behaviors and were treated with two- or three-dimensional radiotherapy (2D/3DRT) or intensity-modulated radiotherapy (IMRT) with a long-term follow up.

METHODS

From 1990 to 2016, 23,325 patients with NPC were included. The primary endpoint of this study was overall survival (OS). The log-rank test and Cox proportional hazards regression model were used to assess the patients' survival outcomes.

RESULTS

The 5-year OS rates in the entire cohort were 76.4%, 68.9%, and 79.8% in the former, current, and never smokers, respectively. In the IMRT cohort, the OS rates showed the same trend. Compared with the never smokers, the 5-year distant metastasis-free survival (DMFS) was lower in the former (P = 0.004) and current smokers (P < 0.001). In the multivariate analysis of the IMRT cohort, the risk of death (P = 0.003) and recurrence (P = 0.027) was higher in the current smokers, while the risk of metastasis was higher in the former and current smokers (P = 0.031 and P = 0.019, respectively) than the never smokers. A total of 53.9% of the effect of smoking status on OS was through sex, age, and Epstein-Barr virus DNA, which were significant mediators.

CONCLUSION

In the IMRT era, being a former smoker or current smoker was an independent risk factor for DMFS. The difference in OS and locoregional relapse-free survival was significant only between the current smokers and never smokers.

The biological function and diagnostic value of miR-762 in nasopharyngeal carcinoma

BACKGROUND

Low diagnostic efficiency and high metastasis and recurrence of nasopharyngeal carcinoma (NPC) result in bad survival. A novel diagnostic biomarker is of great importance for the improvement of NPC management. This study aimed to state the biological function and diagnostic values of miR-762 in NPC to provide a novel insight into the detection and therapy of NPC.

METHODS

The expression of miR-762 in NPC and healthy samples was detected by quantitative real-time polymerase chain reaction and its diagnostic value was evaluated by the receiver operating characteristic (ROC) analysis. The functional roles of miR-762 in the proliferation, migration, and invasion of NPC cells were assessed by CCK8 and Transwell assay.

RESULTS

The significant upregulation of miR-762 was observed in NPC serum compared with healthy controls, which was associated with the TNM stage and lymph node metastasis of NPC patients. The ROC curve showed that miR-762 could be a diagnostic biomarker for NPC with high accuracy and specificity. Additionally, miR-762 served as a tumor promoter, which could promote cell proliferation, migration, and invasion of NPC.

CONCLUSION

The upregulation of miR-762 in NPC is associated with the disease progression and diagnosis of NPC. miR-762 might be involved in the tumor progression of NPC, which provides a potential therapeutic target for the treatment and management of NPC.

Prognostic value of neutrophils for patients with nasopharyngeal carcinoma

OBJECTIVE

To investigate the relationship between absolute neutrophils count (ANC) in different periods of treatment and the outcomes of patients and assess effect of longitudinal neutrophils variation during radiotherapy (RT) on prognosis in patients with nasopharyngeal carcinoma (NPC).

METHODS

A total of 1753 patients with newly diagnosed NPC were retrospectively analyzed. Complete blood counts of patients were obtained before treatment, before, during, and end of RT. The survival rate was calculated by Kaplan-Meier method and the result was compared by the log-rank test. The univariate and multivariate COX regression analyses were performed to investigate the association between the variation of ANC and survival for patients in different periods.

RESULTS

Higher ANC pretreatment (>4 × 109/L) and pre-RT (>7 × 109/L) were correlated with poor OS (89.7% vs 85.6%, P = .009; 88.3% vs 77.3%, P = .002, respectively). An increase >5 × 109/L of ANC during RT was associated with adverse OS (87.9% vs 73.6%, P = .042). The multivariate Cox regression analysis showed that high ANC of pre-RT (>7 × 109/L) and a high increase (>5 × 109/L) of ANC during RT were independent prognostic factors of patients with NPC (P = .002, .044, respectively).

CONCLUSION

Our results demonstrated that ANC was an independent prognostic factor for survival in patients with NPC who received RT. Neutrophils may promote tumor resistance to radiotherapy in NPC.

LEVEL OF EVIDENCE

2a.

MiR-138-1-3p alters the stemness and radiosensitivity of tumor cells by targeting CRIPTO and the JAK2/STAT3 pathway in nasopharyngeal carcinoma

Background

Tumor resistance to radiotherapy is one of the main obstacles to the clinical treatment of nasopharyngeal carcinoma (NPC). Improving the radiosensitivity of tumor cells has an important clinical significance in treatment of clinical NPC. This study aimed to identify that miR-138-1-3p as a novel therapeutic target in radioresistant NPC cells and found its targets, CRIPTO and the JAK2/STAT3 pathway.

Methods

Radioresistant C666-IR and HK-1R cells were derived from the NPC cell lines C666-1 and HK-1. The different microRNAs (miRNAs) and their targeting genes were analyzed between C666-1 and C666-IR cells using microarray bioinformatics. Western blot, qRT-PCR, gene transfection, Luciferase reporter assay, and confocal laser scanning microscopy were applied for the analysis of the different genes.

Results

MiR-138-1-3p was found to target CRIPTO, which involved in the epithelial-mesenchymal transition (EMT) and JAK2/STAT3 signaling pathways. The luciferase reporter assay confirmed that miR-138-1-3p targeted CRIPTO and downregulated the expression of CRIPTO. Furthermore, miR-138-1-3p affected the stability of the CRIPTO-GRP78 complex on the cell membrane and also reversed the radioresistant characteristics of NPC stem cells, which affected EMT and the JAK2/STAT3 signaling pathway.

Conclusions

The miR-138-1-3p is a small molecule that can modulate radiosensitivity in the radioresistant C666-IR and HK-1R NPC cell lines by inhibiting EMT and targeting CRIPTO to reduce the activation of the JAK2/STAT3 pathway.

The appropriate use of circulating EBV-DNA in nasopharyngeal carcinoma: Comprehensive clinical practice guidelines evaluation

BACKGROUND

In EBV-related nasopharyngeal carcinoma (NPC), quantitative determination of circulating EBV-DNA (cEBV-DNA) can potentially be applied as disease marker. The aim of the study was to investigate if the clinical utility of cEBV-DNA is established in clinical practice guidelines and if recommendations are provided to standardize the quantitative cEBV-DNA determination.

METHODS

A systematic literature search for NPC guidelines published since 2011 was performed. Information for cEBV-DNA detection method and use in clinical practice was synthesized in consecutive steps of increasing simplification.

RESULTS

From 570 titles and abstracts identified by the search, 16 guidelines were included. The selected documents were further clustered as either being based on a systematic literature revision to generate recommendations (4/16) or not (12/16). cEBV-DNA was evaluated in only one guideline based on a systematic revision and in 8 guidelines without systematic revision. Half of available guidelines provide recommendation for its clinical use. Methodological issues on cEBV-DNA determination are discussed by 31% of guidelines, without providing any recommendation on method standardization.

CONCLUSIONS

Due to its prognostic value, cEBV-DNA is suggested in the pre-treatment work-up and in the follow-up. Guideline producers need to take into more consideration methodological aspects impacting the actual reliability and generalizability of laboratory results.

A combination of two ELISA tests for nasopharyngeal carcinoma screening in endemic areas based on a case-control study

For populations with a high risk of nasopharyngeal carcinoma (NPC) in Guangdong province in southern China, mass screening is the first choice to prevent death from NPC. To improve the performance of NPC screening, we used a combination based on the IgA antibody against the Epstein-Barr virus (EBV) capsid antigen (VCA-IgA) and the IgA antibody against Epstein-Barr virus nuclear antigen 1 (EBNA1-IgA) to NPC screening by enzyme-linked immunosorbent assay (ELISA). A multiplication model was applied to measure the level of the combination. We evaluated the NPC screening effect of the markers.A case-control study was performed to assess the NPC screening effect of the markers. A total of 10,894 serum specimens were collected, including 554 samples from NPC patients and 10,340 samples from healthy controls. In the training stage, 640 subjects were randomly selected, including 320 NPC cases and 320 healthy controls. In the verification stage, 10,254 subjects were used to verify the NPC screening effect of the combination. Receiver operating characteristic (ROC) analysis was performed. In the verification stage, the combination achieved an sensitivity of 91.45%, a specificity of 93.45%, and an area under the ROC curve (AUC) of 0.978 (95% CI [0.968–0.987]). Compared with VCA-IgA and EBNA1-IgA individually, the combination had an improved screening performance. A probability (PROB) calculated by logistic regression model based on VCA-IgA and EBNA1-IgA was applied to NPC screening by ELISA in China. The AUC of the combination was a little bit larger than the PROB. There was a slight increase (3.13%) in the sensitivity of the combination compared to the sensitivity of the PROB, while the specificity was lower for the combination (92.50%) than for the PROB (95.94%). We successfully applied a combination of two ELISA tests based on VCA-IgA and EBNA1-IgA for NPC screening by using a multiplication model. The results suggested that the combination was effective and can be an option for NPC screening.

Clinicopathological and prognostic features of nasopharyngeal carcinoma in children and adolescents: A retrospective study of 196 cases in South China

Nasopharyngeal carcinoma (NPC) occurring in children and adolescence is extremely rare and till present there is a lack of understanding on their clinicopathological and prognostic features of this rare entity. For our study, data of 196 cases children and adolescents with NPC from the past 18 years at a high-volume cancer center from South China were retrospectively analyzed. Half of the evaluated NPC patients (83/166, 50.0%) were staged as Stage IVa disease, whereas 1.2% (2/166), 27.7% (46/166), 16.9% (28/166) and 4.2% (7/166) had Stage II, III, IVb and IVc disease, respectively. Serum EBV EA-IgA ≥1:10 and VCA-IgA ≥1:40 were found in 67.7% (113/167) and 76.6% (128/167) of the evaluated patients, respectively, whereas 56.8% (84/148) of the patients had plasma EBV DNA ≥1000 copies/mL. Histologically, all tumors were classified as nonkeratinizing squamous cell carcinoma (NK-SCC). Immunohistochemistrically, the expression of CK (AE1/AE3), P63, CK5/6 and P40 were observed in 100% (88/88), 93.2% (68/73), 84.1% (58/69) and 63.2% (12/19) of the detected cases, respectively. All cases show similar immunophenotype compared to that occurring in adult patients. All evaluated cases (71/71 100%) harbored EBER. Patients with plasma EBV DNA ≥1000 copies/mL and positive serum EBV antibodies had significantly inferior 3-year OS (88% vs 100%, P = .007) compared to other corresponding groups. The combination of EBV serology and plasma EBV DNA are useful to predict the outcome of patients with NPC in children and adolescents.

Circulation EBV Mir-Bart-7 Relating to Clinical Manifestation in Nasopharyngeal Carcinoma

OBJECTIVE

Nasopharyngeal Carcinoma (NPC) is an endemic head and neck malignancy in Asia Pacific regions that is associated with chronic infection by Epstein-Barr virus (EBV). EBV miR-BART-7 is a microRNA (miRNA) encoded by EBV that regulates malignant behavior of NPC. However, the role and function of miR-BART7 are not clear, particularly the relation of circulating levels and patient's clinical presentation.

METHODS

Circulating miR-BART-7 levels were measured by using qRT-PCR and were correlated with clinical and pathological data.

RESULT

Of 52 NPC patients included in this study, 85% were diagnosed in the late stages (Stage III-IV). 73% of tumors were non-keratinizing undifferentiated NPC, 92% of tumors were WHO class III histology and all cases were EBV-IgA positive. Over-expression of miR-BART7-3p was correlated with positive regional lymph nodes in newly diagnosed (4.61 fold changes, p <0.05).

CONCLUSION

Over-expression of circulating EBV miR-BART7 correlated with positive regional lymph nodes reflecting the diagnostic and prognostic values of circulating miR-BART7 for patients with NPC.

Chemotherapy and chemo-resistance in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is closely associated with Epstein-Barr virus (EBV) and occurs frequently in the south of China and Southeast Asian countries. Concurrent chemo-radiotherapy is one of the main treatments for NPC. Although, the combined treatment of chemo-radiotherapy produces a satisfying survival rate, the chemo-resistance arises as a big obstacle in curing recurrent NPC patients. The acquirement of chemo-resistance is usually along with a poor prognosis. So far, the mechanism of chemo-resistance in NPC has not been fully elucidated and there have not been a comprehensive review on this issue. Thus, it is of great significance to summarize the mechanisms involved in NPC chemo-resistance. In this review, the importance and limitations of chemotherapy and the mechanisms of chemo-resistances in NPC were discussed.

Circulating Epstein-Barr virus microRNAs BART7-3p and BART13-3p as novel biomarkers in nasopharyngeal carcinoma

Epstein‐Barr virus (EBV) BamHI A rightward transcripts (BART) encoded microRNAs (EBV‐miR‐BARTs) are abnormally highly expressed in nasopharyngeal carcinoma (NPC). This study aims to investigate the diagnostic and prognostic performance of miR‐BART7‐3p and miR‐BART13‐3p. Plasma levels of EBV DNA, miR‐BART7‐3p, and miR‐BART13‐3p were examined by quantitative PCR in 483 treatment‐naïve NPC patients and 243 controls without NPC. The prognostic performance was examined by comparing plasma levels with rates of distant metastasis during follow‐up. The area under the receiver operating characteristic curve for diagnosing NPC was 0.926 for EBV DNA, 0.964 for plasma miR‐BART7‐3p, 0.973 for miR‐BART13‐3p, and 0.997 for all three indices. Among 465 NPC patients without distant metastasis, the above‐median miR‐BART7‐3p and EBV DNA were independent risk for shorter distant metastasis‐free survival (DMFS) (hazard ratio [HR] = 2.94, 95% confidence interval [CI], 1.44‐5.97, P = .003; HR = 2.27, 95% CI, 1.26‐4.10, P = .006) in multivariate Cox regression. Epstein‐Barr virus DNA, miR‐BART7‐3p, and miR‐BART13‐3p after radiotherapy were detectable in 28.6%, 17.6%, and 54.7% of patients, respectively. In multivariate Cox regression, detectable miR‐BART7‐3p and EBV DNA were independent risks for shorter DMFS (HR = 4.13, 95% CI, 1.89‐9.01, P < .001; HR = 2.14, 95% CI, 1.04‐4.42, P = .039). The 4‐year DMFS rate was 92.0% in subjects (n = 156) with neither detectable miR‐BART7‐3p nor EBV DNA, 80.0% in subjects (n = 65) with either detectable miR‐BART7‐3p or EBV DNA, and 52.9% in subjects (n = 24) with both detectable miR‐BART7‐3p and EBV DNA after radiotherapy (P < .001). Circulating levels of miR‐BART7‐3p and miR‐BART13‐3p show excellent diagnostic performance for NPC. The combination of plasma levels of miR‐BART7‐3p and EBV DNA at diagnosis and after radiotherapy could help stratify patients by risk of poor DMFS.

MiRNAs in Radiotherapy Resistance of Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumors of the head and neck in Southeast Asia and southern China. Although the comprehensive treatment based on intensity-modulated radiation therapy improves outcomes, the five-year survival rate of NPC patients is low, and the recurrence remains high. Radiotherapy resistance is the main cause of poor prognosis in NPC patients. MicroRNAs (miRNAs) are a class of endogenous non-coding RNAs regulating various biological functions in eukaryotes. These miRNAs can regulate the development and progression of nasopharyngeal carcinoma by affecting the proliferation, apoptosis, movement, invasion and metastasis of NPC cells. The abnormal expression of miRNAs is closely related to radiotherapy sensitivity and prognosis of NPC patients, which can affect the transmission of related signaling pathways by regulating the expression of tumor suppressor genes and / or oncogenes, and therefore participate in radiotherapy resistance in nasopharyngeal carcinoma. Here, we review the mechanisms by which miRNAs may be involved in the radiotherapy resistance of nasopharyngeal carcinoma.

Comprehensive analysis of key genes associated with ceRNA networks in nasopharyngeal carcinoma based on bioinformatics analysis

BACKGROUND

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy with high morbidity rates in the east and southeast Asia. The molecular mechanisms of NPC remain largely unknown. We explored the pathogenesis, potential biomarkers, and prognostic indicators of NPC.

METHODS

We analyzed mRNAs, long non-coding RNAs (lncRNAs), and microRNAs (miRNAs) in the whole transcriptome sequencing dataset of our hospital (five normal tissues vs. five NPC tissues) and six microarray datasets (62 normal tissues vs. 334 NPC tissues) downloaded from the Gene Expression Omnibus (GSE12452, GSE13597, GSE95166, GSE126683, and GSE70970, GSE43039). Differential expression analyses, gene ontology (GO) enrichment, kyoto encyclopedia of genes and genomes (KEGG) analysis, and gene set enrichment analysis (GSEA) were conducted. The lncRNA-miRNA-mRNA competing endogenous RNA (ceRNA) networks were constructed using the miRanda and TargetScan database, and a protein-protein interaction (PPI) network of differentially expressed genes (DEGs) was built using Search Tool for the Retrieval of Interacting Genes (STRING) software. Hub genes were identified using Molecular Complex Detection (MCODE), NetworkAnalyzer, and CytoHubba.

RESULTS

We identified 61 mRNAs, 14miRNAs, and 10 lncRNAs as shared DEGs related to NPC in seven datasets. Changes in NPC were enriched in the chromosomal region, sister chromatid segregation, and nuclear chromosome segregation. GSEA indicated that the mitogen-activated protein kinase (MAPK) pathway, phosphatidylinositol-3 OH kinase/protein kinase B (PI3K-Akt) pathway, apoptotic pathway, and tumor necrosis factor (TNF) were involved in the initiation and development of NPC. Finally, 20 hub genes were screened out via the PPI network.

CONCLUSIONS

Several DEGs and their biological processes, pathways, and interrelations were found in our current study by bioinformatics analyses. Our findings may offer insights into the biological mechanisms underlying NPC and identify potential therapeutic targets for NPC.