Etiological factors of nasopharyngeal carcinoma

Silencing PARP-1 binding protein Inhibits Cell Migration and Invasion via Suppressing UBE2C in Nasopharyngeal Cancer Cells

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a malignancy with a 2 per 100 000 incidence rate in the world. Overall survival (OS) of patients in stage I-II disease is around 80%, whereas OS of patients in stage III-IVB disease drops to 60%, implying the importance of diagnosis to reduce NPC mortality. However, more than 70% patients of NPC were diagnosed at advanced stages (stage III and IV) in clinics, and it definitely contributes to little substantial improvement in the 5-year survival rates although NPC is sensitive to radio-and chemotherapy. Hence, development of novel biomarkers and targetable genes in NPC is eagerly awaited.

METHODS

We had analyzed the dataset GSE12452 and found hundreds of genes trans-activated in NPC. Among them, this study focused on PARP-1 binding protein (PARPBP) whose overexpression was also validated in GSE13597 and GSE53819 datasets.

RESULTS

Knockdown of PARPBP significantly reduced cell viability in NPC and also identified hundreds of differentially expressed genes including 377 downregulated and 518 upregulated genes in HONE-1 cells with stably knockdown PARPBP. Furthermore, PARPBP might promote cell migration and invasion in NPC through positive regulation of ubiquitin-conjugating enzyme 2C (UBE2C).

CONCLUSION

The results demonstrate the aberrant expression of PARPBP in NPC, and imply its importance in nasopharyngeal carcinogenesis which further opens up the possibility of PARPBP as a novel diagnostic biomarker for NPC therapy.

Nasopharyngeal Carcinoma and Its Effect on Dry Eye Disease: A Nationwide Cohort Study

The aim of the current study was to investigate the relationship between nasopharyngeal carcinoma (NPC) and dry eye disease (DED) using the National Health Insurance Research Database (NHIRD) of Taiwan. A retrospective cohort study was conducted, and patients with an NPC diagnosis were included. Next, one NPC patient was matched to four non-NPC participants via demographic data and systemic comorbidities. In total, 4184 and 16,736 participants were enrolled in the NPC and non-NPC groups, respectively. The primary outcome was the development of DED one year after the diagnosis of NPC. Cox proportional hazard regression was applied to estimate the adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs) of DED. In this study, 717 and 2225 DED cases were found in the NPC and non-NPC groups, respectively, and the NPC group showed a significantly higher incidence of DED development compared to the non-NPC group (aHR: 1.45, 95% CI: 1.33−1.58, p < 0.0001) in the multivariable analysis. The other covariates that were positively correlated with DED development included age over 40 years, an education level higher than senior high school, hypertension, DM, allergic pulmonary diseases, allergic otolaryngologic diseases, and allergic dermatological diseases (all p < 0.05). In conclusion, the presence of NPC is an independent risk factor for subsequent DED.

Serologic Profiling Using an Epstein-Barr Virus Mammalian Expression Library Identifies EBNA1 IgA as a Prediagnostic Marker for Nasopharyngeal Carcinoma

PURPOSE

The favorable prognosis of stage I and II nasopharyngeal carcinoma (NPC) has motivated a search for biomarkers for the early detection and risk assessment of Epstein-Barr virus (EBV)-associated NPC. Although EBV seropositivity is ubiquitous among adults, a spike in antibodies against select EBV proteins is a harbinger of NPC. A serologic survey would likely reveal which EBV antibodies could discriminate those at risk of developing NPC.

EXPERIMENTAL DESIGN

Lysates from a new EBV mammalian expression library were used in a denaturing multiplex immunoblot assay to survey antibodies against EBV in sera collected from healthy individuals who later developed NPC (incident cases) in a prospective cohort from Singapore and validated in an independent cohort from Shanghai, P.R. China.

RESULTS

We show that IgA against EBV nuclear antigen 1 (EBNA1) discriminated incident NPC cases from matched controls with 100% sensitivity and 100% specificity up to 4 years before diagnosis in both Singapore and Shanghai cohorts. Incident NPC cases had a greater IgG repertoire against lytic-classified EBV proteins, and the assortment of IgA against EBV proteins detected by the immunoblot assay increased closer to diagnosis.

CONCLUSIONS

Although NPC tumors consistently harbor latent EBV, the observed heightened systemic and mucosal immunity against lytic-classified antigens years prior to clinical diagnosis is consistent with enhanced lytic transcription. We conclude that an expanding EBV mucosal reservoir (which can be latent and/or lytic) is a risk factor for NPC. This presents an opportunity to identify those at risk of developing NPC using IgA against EBNA1 as a biomarker.

Insight into LncRNA- and CircRNA-Mediated CeRNAs: Regulatory Network and Implications in Nasopharyngeal Carcinoma—A Narrative Literature Review

Nasopharyngeal carcinoma (NPC) is a kind of head-and-neck malignant tumor, and distant metastasis treatment resistance is the leading cause of patient death. In-depth understanding of NPC progression and treatment failure remains to be explored. Long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) are noncoding RNAs that play key regulatory role in shaping tumor cell activities. Recent studies have revealed that lncRNA and circRNA function as competitive endogenous RNAs (ceRNAs) by regulating the posttranscriptional expression of genes as miRNA baits. The imbalanced ceRNA networks derived from lncRNA/circRNA-miRNA-mRNA interaction are widely found to contribute to NPC development. Herein, we summarize typical examples of lncRNA/circRNA-associated ceRNAs in recent years, which involved the potential molecular mechanisms in the regulation of proliferation, apoptosis, treatment resistance and metastasis of NPC, and discuss their potential clinical significance in the prognosis and treatment of NPC. Interpreting the involvement of ceRNAs networks will provide new insight into the pathogenesis and treatment strategies of NPC. However, ceRNA regulatory mechanism has some limitations currently. Screening the most effective ceRNA targets and the clinical application of ceRNA still has many challenges.

Development and validation of the health belief model questionnaire to promote smoking cessation for nasopharyngeal cancer prevention: a cross-sectional study

OBJECTIVE

Lifestyle-induced nasopharyngeal carcinoma is a serious but preventable risk factor. This study serves to develop and validate a questionnaire that aims to predict the health behavioural intention on smoking cessation in Sarawak, Malaysia using the Health Belief Model (HBM).

DESIGN

A cross-sectional study.

SETTING

Urban and suburban areas in Sarawak, Malaysia.

PARTICIPANTS

The preliminary items of the instrument were developed after extensive literature review. The instrument was translated into the Malay language using the forward-backwards method before commencing with the content validity by a panel of 10 experts. Face validity was done both quantitatively and qualitatively by 10 smokers. The construct validity of the instrument was evaluated through exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). A total of 100 smokers participated in phase 1 for EFA, while 171 smokers participated in phase 2 for CFA. Internal consistency was measured using Cronbach's alpha coefficients to evaluate the reliability.

RESULTS

In the exploratory stage, the factor loading of each item remained within the acceptable threshold. The final revised CFA yielded appropriate fit of the seven-factor model with the following model fit indices: χ²=641.705; df=500; p<0.001; comparative fit index=0.953; Tucker-Lewis Index=0.948; root mean square error of approximation=0.041. Satisfactory convergent validity and divergent validity were shown, with the exception of one pairwise construct. The internal reliability of these scales was above the desirable threshold, with Cronbach's alpha coefficients ranging from 0.705 to 0.864 and 0.838 to 0.889 in phases 1 and 2, respectively.

CONCLUSIONS

The study substantiated the instrument to be valid and reliable for predicting smokers' health behavioural intention to reduce cancer risk. The instrument is made up of 34 items, categorised into two sections, six HBM constructs and health behavioural intention. The instrument can be utilised for other smoking cessation-related cancers in different at-risk populations.

Indoleamine 2,3-dioxygenase gene expression and kynurenine to tryptophan ratio correlation with nasopharyngeal carcinoma progression and survival

INTRODUCTION

Indoleamine 2,3-dioxygenase (IDO) is an immunosuppressive tryptophan-depleting enzyme expressed in nasopharyngeal carcinoma (NPC) tissue. However, IDO has not been reported in the peripheral blood of NPC patients. The aim of this study was to analyze, IDO1 and IDO2 messenger RNA (mRNA) expression, the kynurenine (Kyn) and tryptophan (Trp) plasma levels, their clinical values and their relationship with cytokine levels in NPC.

METHODS

We evaluated IDO1 and IDO2 mRNA expression in peripheral blood mononuclear cells (PBMC) by quantitative real-time PCR, plasma Trp and Kyn levels by HPLC, and cytokine levels by ELISA in 75 NPC patients and 51 healthy controls.

RESULTS

Compared to controls, IDO1 mRNA expression was significantly upregulated and IDO2 mRNA expression was significantly downregulated in PBMC of patients. Also compared to controls, plasma Kyn levels and Kyn/Trp ratio were significantly higher in patients. At the time of diagnosis, the plasma Kyn/Trp ratio was associated with advanced cancer status and was an independent prognostic factor for worse disease-specific survival. According to cancer stages, IDO1 mRNA expression was positively correlated with plasma Kyn/Trp ratio in patients with earlier stages (I-II-III) but negatively correlated in patients with the late-stage cancer (IV). Tumor necrosis factor-α, interleukin (IL)-6 and IL-10 levels were significantly higher in patients compared to controls. Moreover, and despite treatment, patients simultaneously carrying high plasma Kyn/Trp ratio and high plasma IL-6 and IL-10 levels at diagnosis died approximately 1 year after first diagnosis.

CONCLUSION

Measuring blood IDO mRNA expression and Kyn/Trp ratio at diagnosis could be a potential marker to evaluate NPC progression and predict survival outcome.

Revealing the crosstalk between nasopharyngeal carcinoma and immune cells in the tumor microenvironment

Nasopharyngeal carcinoma (NPC) arises from the epithelial cells located in the nasopharynx and has a distinct geographic distribution. Chronic Epstein-Barr virus (EBV) infection, as its most common causative agents, can be detected in 100% of NPC types. In-depth studies of the cellular and molecular events leading to immunosuppression in NPC have revealed new therapeutic targets and diverse combinations that promise to benefit patients with highly refractory, advanced and metastatic NPC. This paper reviews the mechanisms by which NPC cells to circumvent immune surveillance and approaches being attempted to restore immunity. We integrate existing insights into anti-NPC immunity and molecular signaling pathways as well as targeting therapies in anticipation of broader applicability and effectiveness in advanced metastatic NPC.

MRI detection of suspected nasopharyngeal carcinoma: a systematic review and meta-analysis

PURPOSE

Endoscopic biopsy is recommended for diagnosis of nasopharyngeal carcinoma (NPC). A proportion of lesions are hidden from endoscopic view but detected with magnetic resonance imaging (MRI). This systematic review and meta-analysis investigated the diagnostic performance of MRI for detection of NPC.

METHODS

An electronic search of twelve databases and registries was performed. Studies were included if they compared the diagnostic accuracy of MRI to a reference standard (histopathology) in patients suspected of having NPC. The primary outcome was accuracy for detection of NPC. Random-effects models were used to pool outcomes for sensitivity, specificity, and positive and negative likelihood ratio (LR). Bias and applicability were assessed using the modified QUADAS-2 tool.

RESULTS

Nine studies were included involving 1736 patients of whom 337 were diagnosed with NPC. MRI demonstrated a pooled sensitivity of 98.1% (95% CI 95.2-99.3%), specificity of 91.7% (95% CI 88.3-94.2%), negative LR of 0.02 (95% CI 0.01-0.05), and positive LR of 11.9 (95% CI 8.35-16.81) for detection of NPC. Most studies were performed in regions where NPC is endemic, and there was a risk of selection bias due to inclusion of retrospective studies and one case-control study. There was limited reporting of study randomization strategy.

CONCLUSION

This study demonstrates that MRI has a high pooled sensitivity, specificity, and negative predictive value for detection of NPC. MRI may be useful for lesion detection prior to endoscopic biopsy and aid the decision to avoid biopsy in patients with a low post-test probability of disease.

CAFS: An Attention-Based Co-Segmentation Semi-Supervised Method for Nasopharyngeal Carcinoma Segmentation

Accurate segmentation of nasopharyngeal carcinoma is essential to its treatment effect. However, there are several challenges in existing deep learning-based segmentation methods. First, the acquisition of labeled data are challenging. Second, the nasopharyngeal carcinoma is similar to the surrounding tissues. Third, the shape of nasopharyngeal carcinoma is complex. These challenges make the segmentation of nasopharyngeal carcinoma difficult. This paper proposes a novel semi-supervised method named CAFS for automatic segmentation of nasopharyngeal carcinoma. CAFS addresses the above challenges through three mechanisms: the teacher-student cooperative segmentation mechanism, the attention mechanism, and the feedback mechanism. CAFS can use only a small amount of labeled nasopharyngeal carcinoma data to segment the cancer region accurately. The average DSC value of CAFS is 0.8723 on the nasopharyngeal carcinoma segmentation task. Moreover, CAFS has outperformed the state-of-the-art nasopharyngeal carcinoma segmentation methods in the comparison experiment. Among the compared state-of-the-art methods, CAFS achieved the highest values of DSC, Jaccard, and precision. In particular, the DSC value of CAFS is 7.42% higher than the highest DSC value in the state-of-the-art methods.

EBV Infection and Its Regulated Metabolic Reprogramming in Nasopharyngeal Tumorigenesis

Viral oncogenes may drive cellular metabolic reprogramming to modulate the normal epithelia cell malignant transformation. Understanding the viral oncogene-mediated signaling transduction dysregulation that involves in metabolic reprogramming may provide new therapeutic targets for virus-associated cancer treatment. Latent EBV infection and expression of viral oncogenes, including latent membrane proteins 1 and 2 (LMP1/2), and EBV-encoded BamH I-A rightward transcripts (BART) microRNAs (miR-BARTs), have been demonstrated to play fundamental roles in altering host cell metabolism to support nasopharyngeal carcinoma (NPC) pathogenesis. Yet, how do EBV infection and its encoded oncogenes facilitated the metabolic shifting and their roles in NPC carcinogenesis remains unclear. In this review, we will focus on delineating how EBV infection and its encoded oncoproteins altered the metabolic reprograming of infected cells to support their malignances. Furthermore, based on the understanding of the host's metabolic signaling alterations induced by EBV, we will provide a new perspective on the interplay between EBV infection and these metabolic pathways and offering a potential therapeutic intervention strategy in the treatment of EBV-associated malignant diseases.

The role of synbiotics in improving inflammatory status in nasopharyngeal carcinoma patients

Nasopharyngeal carcinoma (NPC) is a malignant tumor that grows from the epithelial cells of nasopharynx. NPC has the ability to modify its metabolism and leads the patient to suffer from malnutrition and cachexia, therefore aggravates the occurrence of impaired inflammatory response. Currently, available treatments for NPC are chemotherapy, radiotherapy, or chemoradiotherapy. Despite of its efficacy, these regimens have been known to elicit various inflammation-related side effects including infection, diarrhea, and mucositis. It has long been established that increased activity of inflammatory response is associated to low survival rate in both early and advanced stage of cancer. Furthermore, uncontrolled and dysregulated inflammatory response are significantly correlated with malignant progression of cancer. Considering how pivotal inflammation to malignancy progression, there is a need for effective strategies to modulate inflammatory response. Various strategies have been proposed to improve immune response in NPC patients including dietary supplementation of synbiotics. Synbiotics refers to the manipulation of both probiotics and prebiotics to provide a synergistic benefit to the host by promoting the growth of beneficial bacteria while inhibiting the growth of pathogenic bacteria. There is a growing number of evidences related to the potential of synbiotics in modulating the pro-inflammatory response and improve immune systems in a variety of conditions, including cancer. In this study, we will discuss the immunomodulatory effects of synbiotics in the nasopharyngeal carcinoma occurrences.

NSUN2 Promotes Tumor Progression and Regulates Immune Infiltration in Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is one of the most common malignancies in the head and neck with a complex etiology, such as environmental factors, genetic factors, and Epstein-Barr virus infection. The NOP2/Sun domain family, member 2 (NSUN2) is a methyltransferase of m5C methylation modification that has been reported to be involved in the occurrence and progression of various tumors, but its role in NPC remains unclear. In this study, we found that NSUN2 was upregulated in NPC and predicted a poor prognosis for NPC patients in both GEO datasets and our tissue microarrays containing 125 NPC tissues. Next, we demonstrated that NSUN2 promoted the proliferation, migration, and invasion of NPC cells in vitro. Additionally, the differential expression genes between NSUN2-high and low expression patients were mainly enriched in multi-immune cell activation and proliferation. Furthermore, NSUN2 negatively regulates immune cell infiltration in the tumor microenvironment (TME) of NPC, which indicates that the NSUN2 level may be negatively correlated with the sensitivity of immunotherapy and chemotherapy. In conclusion, our findings highlight that NSUN2 might act as an important oncogene involved in NPC progression and serve as a potential biomarker to predict poor prognosis and drug sensitivity of NPC patients.

Functional Roles of JNK and p38 MAPK Signaling in Nasopharyngeal Carcinoma

c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) family members integrate signals that affect proliferation, differentiation, survival, and migration in a cell context- and cell type-specific way. JNK and p38 MAPK activities are found upregulated in nasopharyngeal carcinoma (NPC). Studies have shown that activation of JNK and p38 MAPK signaling can promote NPC oncogenesis by mechanisms within the cancer cells and interactions with the tumor microenvironment. They regulate multiple transcription activities and contribute to tumor-promoting processes, ranging from cell proliferation to apoptosis, inflammation, metastasis, and angiogenesis. Current literature suggests that JNK and p38 MAPK activation may exert pro-tumorigenic functions in NPC, though the underlying mechanisms are not well documented and have yet to be fully explored. Here, we aim to provide a narrative review of JNK and p38 MAPK pathways in human cancers with a primary focus on NPC. We also discuss the potential therapeutic agents that could be used to target JNK and p38 MAPK signaling in NPC, along with perspectives for future works. We aim to inspire future studies further delineating JNK and p38 MAPK signaling in NPC oncogenesis which might offer important insights for better strategies in diagnosis, prognosis, and treatment decision-making in NPC patients.

The Prognostic Impact of Combined Tumor-Infiltrating Lymphocytes and Pretreatment Blood Lymphocyte Percentage in Locally Advanced Nasopharyngeal Carcinoma

Purpose

To explore the prognostic impact of combined tumor-infiltrating lymphocytes (TILs) and pretreatment peripheral lymphocyte percentage (LYM%) among patients with locally advanced nasopharyngeal carcinoma (LA-NPC).

Patients and Methods

TILs and pretreatment LYM% were retrospectively assessed in 253 LA-NPC patients who underwent chemoradiation therapy between January 2012 and December 2017. According to TILs and LYM% status, the patients were divided into three groups: high-risk group (HRG) (TILs–LYM% score = 0), middle-risk group (MRG) (TILs–LYM% score = 1), and low-risk group (LRG) (TILs–LYM% score = 2). The relationship between TILs level and LYM%, and also the associations of TILs–LYM% status with clinicopathological factors and survival, were evaluated.

Results

As a continuous variable, LYM% was significantly higher in TILs-high group. High TILs or high LYM% alone was significantly related to better 3-year disease-free survival (DFS), overall survival (OS), distant metastasis-free survival (DMFS) and locoregional relapse-free survival (LRRFS), respectively. Kaplan–Meier analysis and log-rank tests also revealed significant decreases in DFS, OS, DMFS, and LRRFS among LA-NPC patients with TILs–LYM% score of 0, 1, and 2 (all P <0.05). Further multivariate analyses showed that TILs–LYM% score was an independent factor affecting survival of the patients, and HRG (TILs–LYM% score = 0) had increased hazard ratios (HRs) for disease (HR = 6.89, P <0.001), death (HR = 8.08, P = 0.008), distant metastasis (HR = 7.66, P = 0.001), and local relapse (HR = 5.18, P = 0.013) compared with LRG (TILs–LYM% score = 2). In receiver operating characteristics (ROC) analyses, TILs–LYM% score had a higher area under the ROC curve (AUC) for the prediction of DFS than did TILs or LYM% alone.

Conclusions

A positive correlation was found between TILs level and pretreatment blood lymphocyte percentage. Moreover, TILs–LYM% score can be considered as a novel independent prognostic indicator of survival outcome among patients with LA-NPC.

Hypermethylation of the RASSF1A gene promoter as the tumor DNA marker for nasopharyngeal carcinoma

BACKGROUND

RASSF1A is a tumor suppressor gene. The methylation of RASSF1A has been reported to be associated with nasopharyngeal tumorigenesis. However, the heterogeneity was high among different studies. A meta-analysis was performed to evaluate the value of RASSF1A methylation for the diagnosis and early screening of nasopharyngeal carcinoma.

METHODS

Relevant articles were identified by searching the MEDLINE database. Frequency and odds ratio (OR) were applied to estimate the effect of CDH-1 methylation based on random-/fixed-effect models. The meta-analysis was performed by using MedCalc^® software. Subgroup analyses were performed by test method, ethnicity, and source of nasopharyngeal carcinoma samples to determine likely sources of heterogeneity.

RESULTS

A total of 17 studies, including 1688 samples (1165 nasopharyngeal carcinoma samples, and 523 from non-cancerous samples) were used for the meta-analysis. The overall frequencies of RASSF1A methylation were 59.68% and 2.65% in case-group and control-group, respectively. By removing the poor relative studies, the heterogeneity was not observed among the studies included. The association between RASSF1A gene methylation and the risk of nasopharyngeal carcinoma was also confirmed by calculating the OR value of 30.32 (95%CI  = 18.22-50.47) in the fixed-effect model (Q = 16.41, p = 0.36,I² = 8.62, 95% CI = 0.00-45.27). Additionally, the significant association was also found between the methylation of the RASSF1A gene and the subgroups.

CONCLUSIONS

This is the first meta-analysis that has provided scientific evidence that the methylation of RASSF1A is the potential diagnosis, prognosis, and early screening biomarker for nasopharyngeal carcinoma.

Radiotherapy for nasopharyngeal cancer

Nasopharyngeal cancers are a rarity in France. Radiotherapy is the cornerstone of treatment, frequently combined with chemotherapy. The technical modality of radiotherapy is complex in this disease, which is located in the vicinity of numerous organs at risk. In this article, we will present the updated guidelines of the French society for radiation oncology (Société française de radiothérapie oncologique, SFRO) on the indications, and technical details of radiotherapy in nasopharyngeal cancers.

Whole exome sequencing identifies the potential role of genes involved in p53 pathway in Nasopharyngeal Carcinoma from Northeast India

Nasopharyngeal Carcinoma (NPC) found to be dependent on geographical and racial variation and is more prevalent in Northeast (NE) India. WES-based study was conducted in three states (tribes); Nagaland (Naga), Mizoram (Mizo) and Manipur (Manipuri), which provided an overview of germline variants involved inthemajor signaling pathways. Validation and recurrence assessment of WES data confirmed the risk effect of STEAP3_rs138941861 and JAG1_rs2273059, and the protective role of PARP4_rs17080653 and TGFBR1_rs11568778 variants, where STEAP3_rs138941861conferring Arg290His substitution was the only exonic non-synonymous variant and to be located in proximity to the linking region between the transmembrane and oxidoreductasedomainsof STEAP3 protein, andaffectedits structural and functional dynamics by altering the Electrostatic Potential around this connecting region. Moreover, these significantly associated variants having deleterious effect were observed to have interactions in p53 signaling pathway which emphasizes the importance of this pathway in the causation of NPC.

MR Imaging of Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma is endemic in parts of the world such as southern China and Southeast Asia. It is predominantly an undifferentiated carcinoma with a strong genetic basis and a close association with the Epstein-Barr virus. The ability of MR imaging to depict the boundaries of the primary tumor and its relationship with the complex structures of the skull base makes it the technique of choice for imaging of this disease in the head and neck. This article describes the MR imaging findings pertinent to staging and management and a new role of MR imaging in early cancer detection, in addition to a brief discussion of differential diagnoses.

Circulating Tumor Cells: A Promising Biomarker in the Management of Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a malignancy that arises from the mucosal epithelium of the nasopharynx, and its prognosis is relatively favorable. The 5-year overall survival rate in patients with locally advanced NPC currently exceeds 80%, but the development of individualized diagnosis and treatment at the molecular level is relatively lacking. Circulating tumor cells (CTCs) is the generic term for tumor cells that are present in the peripheral blood circulation. As a new biomarker with good clinical application prospects, the detection of CTCs has the advantages of being non-invasive, simple, and repeatable. By capturing and detecting CTCs in peripheral blood and monitoring the dynamic variation of its type and quantity, we can assess the biological characteristics of tumor in a timely manner and evaluate the therapeutic effect and prognosis of patients in advance, which will help to develop individualized treatments of tumors. The primary purposes of this review were the clinical application of CTCs in tumor stage determination, treatment efficacy evaluation, and prognosis prediction of NPC. In addition, we estimated the correlation between Epstein-Barr virus infection and CTCs and analyzed the difference in karyotypes and specific markers expressed on CTCs. We believe that our study will provide new insights and biomarkers for the individualized treatment of patients with NPC.

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.

Nasopharyngeal carcinoma: an evolving paradigm

The past three decades have borne witness to many advances in the understanding of the molecular biology and treatment of nasopharyngeal carcinoma (NPC), an Epstein-Barr virus (EBV)-associated cancer endemic to southern China, southeast Asia and north Africa. In this Review, we provide a comprehensive, interdisciplinary overview of key research findings regarding NPC pathogenesis, treatment, screening and biomarker development. We describe how technological advances have led to the advent of proton therapy and other contemporary radiotherapy approaches, and emphasize the relentless efforts to identify the optimal sequencing of chemotherapy with radiotherapy through decades of clinical trials. Basic research into the pathogenic role of EBV and the genomic, epigenomic and immune landscape of NPC has laid the foundations of translational research. The latter, in turn, has led to the development of new biomarkers and therapeutic targets and of improved approaches for individualizing immunotherapy and targeted therapies for patients with NPC. We provide historical context to illustrate the effect of these advances on treatment outcomes at present. We describe current preclinical and clinical challenges and controversies in the hope of providing insights for future investigation.

Nasopharyngeal malignancies in Denmark diagnosed from 1980 to 2014

OBJECTIVES

Nasopharyngeal malignancies are reported having decreasing incidence and reduced mortality. This study provides a nationwide update of the incidence and survival in Denmark.

MATERIALS AND METHODS

The Danish Cancer Registry (DCR) and Central Population Register (CPR) were used to identify all patients registered with nasopharyngeal malignancies between 1980 and 2014 in Denmark. We evaluated the age-adjusted incidence rate (AAIR), average annual percent change (AAPC) and relative survival (RS) and also constructed age-population-cohort (APC) models.

RESULTS

911 patients were identified with a male:female ratio of 2.2:1, a median age of 57.7 years (range 2.8-98.3 years) and an overall median follow-up time of 2.7 years (range 0-37 years). The AAIR was 0.39 cases per 100 000 in 1980 and 0.28 cases per 100 000 in 2014 with an AAPC of -3.2 (95% CI: -7.5; 1.2, p = 0.1). The overall 1-year and 5-year RS rates were 76.3% and 42.1%, respectively. We found a significant age effect in the APC model for the incidence of nasopharyngeal malignancies, but no significant cohort or period effects.

CONCLUSION

The incidence of nasopharyngeal carcinomas has slightly decreased over the last four decades, however insignificantly. Meanwhile, the relative survival has increased significantly in Denmark since 1980. The cause of improved relative survival might be attributed to altered treatment practices.

SSTR2 in Nasopharyngeal Carcinoma: Relationship with Latent EBV Infection and Potential as a Therapeutic Target

Nasopharyngeal carcinoma (NPC) is a malignant epithelial tumor, most commonly located in the pharyngeal recess and endemic to parts of Asia. It is often detected at a late stage which is associated with poor prognosis (5-year survival rate of 63%). Treatment for this malignancy relies predominantly on radiotherapy and/or systemic chemotherapy, which can be associated with significant morbidity and impaired quality of life. In endemic regions NPC is associated with infection by Epstein-Barr virus (EBV) which was shown to upregulate the somatostatin receptor 2 (SSTR2) cell surface receptor. With recent advances in molecular techniques allowing for an improved understanding of the molecular aetiology of this disease and its relation to SSTR2 expression, we provide a comprehensive and up-to-date overview of this disease and highlight the emergence of SSTR2 as a key tumor biomarker and promising target for imaging and therapy.

Epigenetic Inactivation of Acetyl-CoA Acetyltransferase 1 Promotes the Proliferation and Metastasis in Nasopharyngeal Carcinoma by Blocking Ketogenesis

The dysregulation of epigenetic modification and energy metabolism cooperatively contribute to the tumorigenesis of nasopharyngeal carcinoma (NPC). However, the detailed mechanisms underlying their joint contribution to NPC development and progression remain unclear. Here, we investigate the role of Acy1 Coenzyme A Acyltransferases1 (ACAT1), a key enzyme in the metabolic pathway of ketone bodies, in the proliferation and metastasis of NPC and to elucidate the underlying molecular mechanisms. Ketogenesis, plays a critical role in tumorigenesis. Previously, we reported two enzymes involved in ketone body metabolism mediate epigenetic silencing and act as tumor suppressor genes in NPC. Here, we identify another key enzyme, Acetyl-CoA acetyltransferase 1 (ACAT1), and show that its transcriptional inactivation in NPC is due to promoter hypermethylation. Ectopic overexpression of ACAT1 significantly suppressed the proliferation and colony formation of NPC cells in vitro. The migratory and invasive capacity of NPC cells was inhibited by ACAT1. The tumorigenesis of NPC cells overexpressing ACAT1 was decreased in vivo. Elevated ACAT1 in NPC cells was accompanied by an elevated expression of CDH1 and a reduced expression of vimentin and SPARC, strongly indicating that ACAT1 is involved in regulating epithelial-mesenchymal transition (EMT). We also found that ACAT1 contributes to increased intracellular levels of β-hydroxybutyrate (β-HB). Exogenously supplied β-HB significantly inhibits the growth of NPC cells in a dose-dependent manner. In summary, ACAT1 may function as a tumor suppressor via modulation of ketogenesis and could thus serve as a potential therapeutic target in NPC. In summary, our data suggest that regulation of ketogenesis may serve as adjuvant therapy in NPC.

A comprehensive risk score for effective risk stratification and screening of nasopharyngeal carcinoma

Using Epstein-Barr virus (EBV)-based markers to screen populations at high risk for nasopharyngeal carcinoma (NPC) is an attractive preventive approach. Here, we develop a comprehensive risk score (CRS) that combines risk effects of EBV and human genetics for NPC risk stratification and validate this CRS within an independent, population-based dataset. Comparing the top decile with the bottom quintile of CRSs, the odds ratio of developing NPC is 21 (95% confidence interval: 12-37) in the validation dataset. When combining the top quintile of CRS with EBV serology tests currently used for NPC screening in southern China, the positive prediction value of screening increases from 4.70% (serology test alone) to 43.24% (CRS plus serology test). By identifying individuals at a monogenic level of NPC risk, this CRS approach provides opportunities for personalized risk prediction and population screening in endemic areas for the early diagnosis and secondary prevention of NPC.

Ginkgolic Acid Suppresses Nasopharyngeal Carcinoma Growth by Inducing Apoptosis and Inhibiting AKT/NF-κB Signaling

Even though nasopharyngeal carcinoma (NPC) is not common worldwide, it is a major public health burden in endemic areas. Distant metastasis often leads to a poor prognosis for NPC; therefore, new and effective anticancer strategies are needed. Ginkgolic acid (GA) is small-molecule compound existing in Ginkgo biloba that has various biologically relevant activities, including antitumor properties; however, its effects and mechanism of action in NPC are unknown. The effects of GA on NPC and such underlying mechanisms were investigated using 5-8F and CNE2 cells and NP69 human immortalized nasopharyngeal epithelial cells in this study. Moreover, the xenograft models were built to examine GA's effection in vivo. GA treatment decreased the survival and invasive capacity of 5-8F and CNE2 and induced their apoptosis, which varied with dose; this was accompanied by downregulation of B cell lymphoma (Bcl)2, upregulation of Bcl2-associated X protein, and activation of poly-ADP ribose polymerase, and caspase-9/-3. G0/G1 phase arrest was induced by GA in NPCs. It also reduced the expression of cyclin-dependent kinase 6 and its regulators cyclin D2 and cyclin D3. GA inhibited the activation of protein kinase B/nuclear factor signaling; this effect was potentiated with GA and 5-fluorouracil (5-FU), which also enhanced 5-FU-induced apoptosis. In summary, GA may be effective as an adjuvant to conventional chemotherapy drugs in preventing the progression of NPC.

Promoter Hypermethylation of Tumor Suppressor Genes Located on Short Arm of the Chromosome 3 as Potential Biomarker for the Diagnosis of Nasopharyngeal Carcinoma

DNA methylation, the most common epigenetic alteration, has been proven to play important roles in nasopharyngeal carcinoma (NPC). Numerous tumor suppressor genes located on the chromosome 3p, particularly in the region of 3p21, are frequently methylated in NPC, thus suggesting great potential for diagnosis of NPC. In this review, we summarize recent findings of tumor suppressor genes on chromosome 3 that likely drive nasopharyngeal tumor development and progression, based on previous studies related to the hypermethylation of these target genes. Better understanding will allow us to design further experiments to establish a potential test for diagnosis of NPC, as well as bring about methylated therapies to improve the treatment of NPC.

Nasopharyngeal carcinoma among the Bidayuh of Sarawak, Malaysia: History and risk factors

Nasopharyngeal carcinoma (NPC) is a cancer of the epithelial cells lining the nasopharynx. The incidence of NPC has a distinct geographical distribution, mainly affecting the Chinese population of Southern China. In Malaysia, this cancer is exceptionally prevalent among males. There is a high incidence rate of NPC among the Bidayuh natives in Sarawak, Malaysia. Other than epidemiology reports, there has not been an article describing plausible cancer risk factors contributing to NPC within this native group. Researchers are still trying to understand the reasons the Bidayuh and Southern Chinese are highly susceptible to NPC. This article discusses the risk factors of developing NPC: Epstein-Barr virus infection, genetic predisposition, diet, environmental exposure and tobacco smoking. There is a need to improve the understanding of the role of risk factors to identify new ways to prevent cancer, especially among high-risk groups.

miR-137/ERRα axis mediates chemoresistance of nasopharyngeal carcinoma cells

Nasopharyngeal carcinoma (NPC) is the most common malignant tumor of the head and neck region and is characterized by an increased risk of developing chemoresistance after treatment. The present study demonstrated that estrogen-related receptor α (ERRα) was upregulated in cisplatin- and fluorouracil-resistant NPC cells. In addition, ERRα knockdown or treatment of cells with the ERRα inverse agonist XCT-790 attenuated the chemoresistance of NPC cells. Mechanistically, the increased expression of ERRα in chemoresistant cells was associated with enhanced mRNA stability. Bioinformatics analysis for screening microRNAs (miRs) regulating the expression of ERRα revealed that miR-137 was downregulated in chemoresistant NPC cells. Additionally, transfection of cells with miR-137 mimics reduced ERRα mRNA stability and increased the chemosensitivity of NPC cells. Furthermore, ERRα knockdown reduced glucose consumption, and lactate and ATP production rates in chemoresistant cells. The aforementioned findings suggested that the miR-137/ERRα-mediated metabolic programming could be involved in the chemoresistance of NPC cells.

Association of tumor downstaging after neoadjuvant chemotherapy with survival in patients with locally advanced nasopharyngeal carcinoma: a retrospective cohort study

PURPOSE

Assessing the downstaging effects of neoadjuvant chemotherapy (NACT) in patients with locally advanced nasopharyngeal carcinoma (LANPC) and predicting response to treatment remain challenging. The present study aimed to evaluate the long-term prognosis of downstaging after NACT in patients with LANPC and to investigate the prognostic value of post-NACT tumor downstaging on treatment outcomes in the era of concurrent chemoradiotherapy (CCRT).

METHODS

This retrospective study included 226 patients with stage III (n = 188) and IVA (n = 38) NPC admitted to Haikou People's Hospital between 1 October 2009 and 1 October 2012. The patients were grouped as downstaging or no after NACT. Overall survival (OS), locoregional failure-free survival (LFFS), and distant failure-free survival (DFFS) were analyzed.

RESULTS

Among 226 patients, 196 (86.7%) were in the downstaging group and 30 (13.3%) were in the non-downstaging group. The longest follow-up was 76 months, and the median was 45 months. The 3-year OS rates of the downstaging group and non-downstaging group were 91.0% (95% CI 0.89-0.93) and 69.5% (95% CI 0.66-0.72) (P = 0.005). The 5-year OS rates were 81.6% (95% CI 0.78-0.86) and 53.3% (95% CI 0.49-0.61) (P = 0.001). N downstaging (3-year OS, HR 0.491, 95% CI 0.221-0.881, P = 0.022; 5-year OS, HR = 0.597, 95% CI 0.378-0.878, P = 0.021) was independently associated with OS.

CONCLUSION

In the treatment of LANPC, the patients with downstaging after NACT have a better prognosis than those without downstaging. This study suggests that NACT can improve the prognosis for patients with LANPC if there is downstaging.

Current approach and novel perspectives in nasopharyngeal carcinoma: the role of targeting proteasome dysregulation as a molecular landmark in nasopharyngeal cancer

Nasopharyngeal carcinoma (NPC) represents a molecularly paradigmatic tumor given the complex diversity of environmental as well as host dependent factors that are closely implicated in tissue transformation and carcinogenesis. Epstein Barr Virus (EBV) plays a key role in tissue invasion, hyperplasia and malignant transformation. Therefore, EBV related oncoviral proteins such as Latent Membrane Protein family (LMP1, LMP2), Epstein Barr Nuclear Antigen 1 (EBNA1) and EBV related glycoprotein B (gB) are responsible for inducing intracellular signalling aberrations leading to sustained proliferation and further acquisition of NPC related invasive nature and metastatic potential.Dysregulation of proteasome signaling seems to be centrally implicated in oncoviral protein stabilization as well as in modulating tumor microenvironment. Different studies in vitro and in vivo suggest a potential role of proteasome inhibitors in the therapeutic setting of NPC. Furthermore, alterations affecting proteasome signalling in NPC have been associated to tumor growth and invasion, distant metastasis, immune exclusion and resistance as well as to clinical poor prognosis. So on, recent studies have shown the efficacy of immunotherapy as a suitable therapeutic approach to NPC. Nevertheless, novel strategies seem to look for combinatorial regimens aiming to potentiate immune recognition as well as to restore both primary and acquired immune resistance.In this work, our goal is to thoroughly review the molecular implications of proteasome dysregulation in the molecular pathogenesis of NPC, together with their direct relationship with EBV related oncoviral proteins and their role in promoting immune evasion and resistance. We also aim to hypothesize about the feasibility of the use of proteasome inhibitors as part of immunotherapy-including combinatorial regimens for their potential role in reversing immune resistance and favouring tumor recognition and eventual tumor death.

The prognostic significance of race in nasopharyngeal carcinoma by histological subtype

BACKGROUND

Race has been shown to have variable prognostic importance in nasopharyngeal carcinoma (NPC). However, previous studies are limited by a lack of comprehensive treatment, epidemiologic, and comorbidity data.

METHODS

This was a retrospective cohort study utilizing the National Cancer Database from 2004 to 2016. Multivariable Cox proportional hazards regressions were used to calculate adjusted hazard ratios (aHR) for overall survival.

RESULTS

A cohort of 9995 patients met inclusion and exclusion criteria. Race, insurance, comorbidity, treatment, stage, age, and histology were independent prognosticators. Among patients with keratinizing NPC, Asians and Hispanics had superior survival (aHR 0.58 [95% confidence interval (CI) 0.48-0.69], aHR 0.76 [95% CI 0.61-0.96]) compared to white patients. Among patients with non-keratinizing differentiated NPC, Asians and black patients had improved survival (aHR 0.71 [95% CI 0.56-0.91], aHR 0.72 [95% CI 0.54-0.95]) compared to white patients. Race was not prognostic in non-keratinizing undifferentiated NPC.

CONCLUSION

The prognostic significance of race varies across histological subtypes of NPC.

Genetic Patterns Found in the Nuclear Localization Signals (NLSs) Associated with EBV-1 and EBV-2 Provide New Insights into Their Contribution to Different Cell-Type Specificities

Simple Summary

The Epstein–Barr virus (EBV) has been implicated in several human neoplastic diseases. The EBV-1 can transform B cells into LCL more efficiently than EBV-2, and EBV-2 preferentially infects T-cell lymphocytes. The EBNA3A oncoprotein has an essential role in B-cell transformation. The six peptide motifs called nuclear localization signals (NLSs) from EBNA3A ensure nucleocytoplasmic protein trafficking. Multiple NLSs have been suggested to enhance EBNA3 function or different specificities to different cell types; however, a comprehensive assessment of their genetic variability has not been addressed. Our objective was to study the NLSs’ variability and their relationship with EBV types. Based on a comprehensive analysis of over a thousand EBNA3A sequences from different clinical manifestations and geographic locations, we found that EBNA3A from EBV-2 has two of the six NLSs altered, and genetic patterns in the NLSs are associated with EBV-1 and EBV-2.

Abstract

The Epstein–Barr virus (EBV) is a globally dispersed pathogen involved in several human cancers of B-cell and non-B-cell origin. EBV has been classified into EBV-1 and EBV-2, which have differences in their transformative ability. EBV-1 can transform B-cells into LCL more efficiently than EBV-2, and EBV-2 preferentially infects T-cell lymphocytes. The EBNA3A oncoprotein is a transcriptional regulator of virus and host cell genes, and is required in order to transform B-cells. EBNA3A has six peptide motifs called nuclear localization signals (NLSs) that ensure nucleocytoplasmic protein trafficking. The presence of multiple NLSs has been suggested to enhance EBNA3 function or different specificities in different cell types. However, studies about the NLS variability associated with EBV types are scarce. Based on a systematic sequence analysis considering more than a thousand EBNA3A sequences of EBV from different human clinical manifestations and geographic locations, we found differences in NLSs’ nucleotide structures among EBV types. Compared with the EBNA3A EBV-1, EBNA3A EBV-2 has two of the six NLSs altered, and these mutations were possibly acquired by recombination. These genetic patterns in the NLSs associated with EBV-1 and EBV-2 provide new information about the traits of EBNA3A in EBV biology.

Research status and prospects of biomarkers for nasopharyngeal carcinoma in the era of high‑throughput omics (Review)

As a malignant tumor type, nasopharyngeal carcinoma (NPC) is characterized by distinct geographical, ethnic and genetic differences; presenting a major threat to human health in many countries, especially in Southern China. At present, no accurate and effective methods are available for the early diagnosis, efficacious evaluation or prognosis prediction for NPC. As such, a large number of patients have locoregionally advanced NPC at the time of initial diagnosis. Many patients show toxic reactions to overtreatment and have risks of cancer recurrence and distant metastasis owing to insufficient treatment. To solve these clinical problems, high‑throughput '‑omics' technologies are being used to screen and identify specific molecular biomarkers for NPC. Because of the lack of comprehensive descriptions regarding NPC biomarkers, the present study summarized the research progress that has been made in recent years to discover NPC biomarkers, highlighting the existing problems that require exploration. In view of the lack of authoritative reports at present, study design factors that affect the screening of biomarkers are also discussed here and prospects for future research are proposed to provide references for follow‑up studies of NPC biomarkers.

Migration of immortalized nasopharyngeal epithelia and carcinoma cells through porous membrane in 3D platforms

In the present study, 3D biomimetic platforms were fabricated with guiding grating to mimic extracellular matrix topography, porous membrane to resemble the epithelial porous interface and trenches below to represent blood vessels as an in vitro tissue microenvironment. Fabrication technologies were developed to integrate the transparent biocompatible polydimethylsiloxane platforms with preciously controlled dimensions. Cell migration behaviors of an immortalized nasopharyngeal epithelial cell line (NP460) and a nasopharyngeal carcinoma cell line (NPC43) were studied on the 2D and 3D platforms. The NP460 and NPC43 cells traversing through the porous membrane and migrating in the trenches below were studied by time-lapse imaging. Before traversing through the pores, NP460 and NPC43 cells migrated around the pores but NPC43 cells had a lower migration speed with less lamellipodia spreading. After traversing to trenches below, NPC43 cells moved faster with an alternated elongated morphology (mesenchymal migration mode) and round morphology (amoeboid migration mode) compared with only mesenchymal migration mode for NP460 cells. The cell traversing probability through porous membrane on platforms with 30 μm wide trenches below was found to be the highest when the guiding grating was perpendicular to the trenches below and the lowest when the guiding grating was parallel to the trenches below. The present study shows important information on cell migration in complex 3D microenvironment with various dimensions and could provide insight for pathology and treatment of nasopharyngeal carcinoma.

Prognostic models for 1-year survival of NPC after radiotherapy in different ages

PURPOSE

Previous studies have shown that approximately 10% of nasopharyngeal cancer (NPC) patients die within a year of disease onset, and that age is an independent predictor. However, no predictive model has been developed. We aimed to establish novel prognostic models to predict the 1-year cancer-specific survival (CSS) of young, middle-aged, and older patients with NPC after radiotherapy.

METHODS

The data of 2822 NPC patients who underwent radiotherapy between 2004 and 2015 were reviewed from the surveillance, epidemiology, and end results database. We divided them into young, middle-aged, and older people groups according to age (< 44 years, 45-59 years, and ≥ 60 years, respectively). Multivariate analyses were performed, and prognostic models were constructed.

RESULTS

Multivariate analyses indicated that age, ethnicity, histological subtype, T, and M stage were independent predictors of 1-year CSS in the older people group. In contrast, ethnicity and age were not found to have predictive value in the young and middle-aged groups, respectively. Accordingly, three prognostic models with excellent predictive values were established for the three groups (C-indices: 0.791 [95% CI 0.722-0.859], 0.763 [95% CI 0.721-0.806] and 0.723 [95% CI 0.683-0.763], respectively). These predictive values are higher than those of the eighth edition American joint committee cancer tumor-node-metastasis (TNM) classification system.

CONCLUSION

Three prognostic models for predicting the 1-year CSS of young, middle-aged, and older NPC patients after radiotherapy showed better predictive power than the TNM classification system. These models may guide treatment strategies and clinical decision-making in different cohorts.

Ubiquitin Carboxyl-Terminal Hydrolases and Human Malignancies: The Novel Prognostic and Therapeutic Implications for Head and Neck Cancer

Ubiquitin C-terminal hydrolases (UCHs), a subfamily of deubiquitinating enzymes (DUBs), have been found in a variety of tumor entities and play distinct roles in the pathogenesis and development of various cancers including head and neck cancer (HNC). HNC is a heterogeneous disease arising from the mucosal epithelia of the upper aerodigestive tract, including different anatomic sites, distinct histopathologic types, as well as human papillomavirus (HPV)-positive and negative subgroups. Despite advances in multi-disciplinary treatment for HNC, the long-term survival rate of patients with HNC remains low. Emerging evidence has revealed the members of UCHs are associated with the pathogenesis and clinical prognosis of HNC, which highlights the prognostic and therapeutic implications of UCHs for patients with HNC. In this review, we summarize the physiological and pathological functions of the UCHs family, which provides enlightenment of potential mechanisms of UCHs family in HNC pathogenesis and highlights the potential consideration of UCHs as attractive drug targets.

Somatostatin receptor 2 expression in nasopharyngeal cancer is induced by Epstein Barr virus infection: impact on prognosis, imaging and therapy

Nasopharyngeal cancer (NPC), endemic in Southeast Asia, lacks effective diagnostic and therapeutic strategies. Even in high-income countries the 5-year survival rate for stage IV NPC is less than 40%. Here we report high somatostatin receptor 2 (SSTR2) expression in multiple clinical cohorts comprising 402 primary, locally recurrent and metastatic NPCs. We show that SSTR2 expression is induced by the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) via the NF-κB pathway. Using cell-based and preclinical rodent models, we demonstrate the therapeutic potential of SSTR2 targeting using a cytotoxic drug conjugate, PEN-221, which is found to be superior to FDA-approved SSTR2-binding cytostatic agents. Furthermore, we reveal significant correlation of SSTR expression with increased rates of survival and report in vivo uptake of the SSTR2-binding 68Ga-DOTA-peptide radioconjugate in PET-CT scanning in a clinical trial of NPC patients (NCT03670342). These findings reveal a key role in EBV-associated NPC for SSTR2 in infection, imaging, targeted therapy and survival.

Separation of nasopharyngeal epithelial cells from carcinoma cells on 3D scaffold platforms

Scaffold microstructures were developed to mimic a three-dimensional extracellular matrix in studying cell migration and invasion. The multiple-layer scaffold platforms were designed to investigate cell migration and separation from top to bottom layer. Two cell lines including immortalized nasopharyngeal epithelial (NP460) cells and nasopharyngeal carcinoma (NPC43) cells with Epstein-Barr virus were compared in this study. On one-layer platforms with trench depth of 15 µm, both NP460 and NPC43 cells were guided to migrate along the 18-µm-wide trenches, and exhibited random migration directions when the trench width was 10 or 50 µm. Nearly no cell was found to migrate in the 10-µm-wide trenches on one-layer platforms. However, the NP460 and NPC43 cells showed very different probability in the narrow trenches on two-layer platforms, making it possible to separate the nasopharyngeal epithelial cells from the carcinoma cells. Moreover, 1-µm deep grating topography on the top layer inhibited NP460 cells to migrate from top ridges to the 10-µm-wide trenches, but promoted such behavior for NPC43 cells. The results demonstrated in This study suggest that the engineered multiple-layer scaffold platforms could be used to separate carcinoma cells in NPC tumor as a potential treatment of NPC.

A Nomogram Based on Serum Biomarkers and Clinical Characteristics to Predict Survival in Patients With Non-Metastatic Nasopharyngeal Carcinoma

Objective

This study focused on developing an effective nomogram for improving prognostication for patients with primary nasopharyngeal carcinoma (NPC) restaged according to the eighth edition of the AJCC/UICC TNM staging system.

Methods

Based on data of 5,903 patients with non-metastatic NPC (primary cohort), we used Cox regression analysis to identify survival risk factors and created a nomogram. We used the nomogram to predict overall survival (OS), distant metastasis-free survival (DMFS) and disease-free survival (DFS) in the primary and independent validation (3,437 patients) cohorts. Moreover, we compared the prognostic accuracy between the 8th TNM system and the nomogram.

Results

The nomogram included gender, age, T stage, N stage, Epstein–Barr virus DNA, hemoglobin, C-reactive protein, lactate dehydrogenase, and radiotherapy with/without induction or concurrent chemotherapy. In the prediction of OS, DMFS and DFS, the nomogram had significantly higher concordance index (C-index) and area under ROC curve (AUC) than the TNM system alone. Calibration curves demonstrated satisfactory agreements between nomogram-predicted and observed survival. The stratification in different groups permitted remarkable differentiation among Kaplan–Meier curves for OS, DMFS, and DFS.

Conclusion

The nomogram led to a more precise prognostic prediction for NPC patients in comparison with the 8th TNM system. Therefore, it could facilitate individualized and personalized patients’ counseling and care.

The prognostic role of prognostic nutritional index in nasopharyngeal carcinoma: A systematic review and meta-analysis

PURPOSE

The prognostic utility of the prognostic nutritional index (PNI) in nasopharyngeal carcinoma (NPC) has never been systematically reviewed. Therefore, we performed this meta-analysis.

METHODS

We performed comprehensive research via Embase, PubMed, Web of Science and the Cochrane Library. The pooled hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were applied to explore the relationship between PNI and overall survival (OS), progression-free survival (PFS), locoregional failure-free survival (LRFFS), distant metastasis-free survival (DMFS) and clinical features. Both univariate analysis (UVA) and multivariate analysis (MVA) were used.

RESULTS

A total of 8 eligible studies including 3631 patients were ultimately enrolled. A low PNI level was significantly associated with a shorter OS [(HR 2.06, P < 0.00001; UVA) and (HR 1.78, P < 0.00001; MVA)], PFS [(HR 2.27, P = 0.006; UVA) and (HR 1.45, P = 0.0003; MVA)] and DMFS [(HR 2.06, P < 0.00001; UVA) and (HR 2.04, P < 0.00001; MVA)]. However, only one study reported the LRFFS of NPC patients, and there was no significant difference [HR 1.68, P = 0.26]. Furthermore, female patients, higher tumor stage, a lower alanine transaminase (ALT) level and a lower white blood cell (WBC) level were associated with a lower PNI level.

CONCLUSION

Our meta-analysis indicated that NPC patients with a low PNI level had worse OS, PFS and DMFS, and a low PNI level was associated with female patients, higher tumor stage, a lower ALT level and a lower WBC level. These findings indicate that PNI is a promising prognostic biomarker.

Risk of nasopharyngeal carcinoma in patients with chronic rhinosinusitis: A nationwide propensity score matched study in Taiwan

AIMS

Chronic inflammation is linked to cancer. This study aims to evaluate the association between chronic rhinosinusitis (CRS) and nasopharyngeal carcinoma (NPC) through a Taiwanese nationwide database.

METHODS

We used the National Health Insurance Research Database between January 1, 2003, and December 31, 2012. The starting date is either the date of the first clinical visit or the diagnosis of CRS. Patients were followed up until the first occurrence of target disease or the last date of medical record. Propensity score 1 to 2 matching was used to match pairs of patients with/without CRS.

RESULTS

A total of 951 380 eligible patients were included in our study, with 36 210 patients diagnosed with CRS. After 1 to 2 propensity score matching, non-CRS cohort consisted of 69 258 patients and CRS cohort consisted of 34 629 patients. CRS was associated with the risk of developing NPC (adjusted OR = 2.23; 95% CI, 1.61-3.09). However, no significant association among CRS and NPC was observed in patients followed up for more than 1 year (adjusted OR = 1.16; 95% CI, 0.76-1.78).

CONCLUSIONS

Patients with CRS diagnosis have relationship with developing NPC within 1 year of follow-up, but not for longer intervals. The short-term association may be due to reversed causation or biased diagnosis. Accordingly, the study suggests CRS a weak role for NPC.

Undifferentiated nasopharyngeal cancer extending to maxillary sinus: a case report

Undifferentiated nasopharyngeal cancer of the cavum (UCNT) is the most frequent neoplasm of the nasopharynx, having a close relationship with exposure to Epstein-Barr virus. It has a high potential for locoregional or distant invasion which are the cause of some treatment failures. The extension to the maxillary sinus is rarely described. We report here the case of a 38-year-old patient with headaches associated with epistaxis, left otalgia and facial pain. Examination by anterior rhinoscopy objectively revealed a polylobed ulcerating mass. Otoscopic examination revealed a left seromucous otitis media. Computed tomography showed a voluminous tumour process in the infra temporal fossa and nasopharynx with significant locoregional extension particularly in the maxillary sinus. Pathological examination revealed an UCNT of the cavum and the patient was classified as T4N2M0. The patient received chemoradiotherapy, with wide irradiation of the cervical lymph node areas. The deep localization of the cancer of the cavum, which is difficult to examine, requires a diagnostic and extension work-up, both endoscopic and radiological, which is an important step in the diagnostic and therapeutic management.

Combination of Plasma MIF and VCA-IgA Improves the Diagnostic Specificity for Patients With Nasopharyngeal Carcinoma

INTRODUCTION

The purpose of this study is to evaluate the diagnostic value of macrophage migration inhibitory factor in patients with nasopharyngeal carcinoma.

MATERIALS AND METHODS

The expression levels of macrophage migration inhibitory factor in nasopharyngeal carcinoma cell lines, tumor tissues, and plasma were measured by real-time polymerase chain reaction, Western blotting, enzyme-linked immunosorbent assay, and immunohistochemistry. Plasma Epstein-Barr virus viral capsid antigen was determined by immunoenzymatic techniques.

RESULTS

Both the messenger RNA and protein expression levels of macrophage migration inhibitory factor were upregulated in nasopharyngeal carcinoma cell lines and nasopharyngeal carcinoma tissues. Macrophage migration inhibitory factor in plasma was significantly elevated in patients with nasopharyngeal carcinoma compared to Epstein-Barr virus viral capsid antigen-negative and Epstein-Barr virus viral capsid antigen-positive healthy donors. The combination of macrophage migration inhibitory factor and Epstein-Barr virus viral capsid antigen was better for diagnosing nasopharyngeal carcinoma (area under receiver operating characteristic curve = 0.925, 95% CI: 0.898-0.951) than macrophage migration inhibitory factor (area under receiver operating characteristic curve = 0.778, 95% CI: 0.732-0.824) and Epstein-Barr virus viral capsid antigen. Combining macrophage migration inhibitory factor and Epstein-Barr virus viral capsid antigen had higher specificity (82.40% vs 69.96%) and higher positive predictive value (79.17% vs 67.44%) without an obvious reduction in sensitivity (95.25%) compared to Epstein-Barr virus viral capsid antigen alone. Macrophage migration inhibitory factor was highly expressed in nasopharyngeal carcinoma cell lines, whereas it was not associated with Epstein-Barr virus infection. The level of macrophage migration inhibitory factor in plasma was not related to the titer of Epstein-Barr virus viral capsid antigen.

CONCLUSION

The combination of macrophage migration inhibitory factor and Epstein-Barr virus viral capsid antigen increases the specificity and positive predictive value of detecting nasopharyngeal carcinoma and improves the diagnostic accuracy of nasopharyngeal carcinoma in high-risk individuals.

Rare cancers are not rare in Asia as well: The rare cancer burden in East Asia

INTRODUCTION

Epidemiologic information on rare cancers is scarce outside of the Western countries. The project "surveillance of rare cancers in Asia" (RARECAREnet Asia) provides, for the first time, the burden of rare cancers in some Asian countries based on the latest list.

OBJECTIVES

1) to assess whether the European list of rare cancers fits the Asian setting and 2) to compare the incidences of rare cancers between Europe and Asian countries.

MATERIAL AND METHODS

Population-based cancer registry data on patients diagnosed from 2011 to 2015 in Japan, Korea, and Taiwan and patients diagnosed from 2000 to 2007 in 94 European registries were analysed. The incidences for all cancers were calculated; they were then grouped into several tiers and families according to the rare cancer list, and whether cancers rare was examined.

RESULTS

Rare cancer counts according to the list in the observed population were 196 in Japan, 203 in Korea, 198 in Taiwan, and 198 in the EU. The proportions of rare in overall incidence were 16.3% in Japan, 23.7% in Korea, 24.2% in Taiwan, and 22.2% in the EU. The numbers of newly diagnosed rare cancer cases in 2015 were 140,188 in Japan, 52,071 in Korea, and 24,147 in Taiwan.

CONCLUSION

Most rare cancers in Europe were also rare in the Asian countries considered. The observed differences were due to well-known risk factors. The European definition and list of rare cancers appear to reflect well cancer incidence in East Asia.

Traversing behavior of tumor cells in three-dimensional platforms with different topography

Three-dimensional polydimethylsiloxane platforms were developed to mimic the extracellular matrix with blood vessels by having scaffolds with micropatterns, porous membrane and trenches. Precisely controlled physical dimensions, layouts, and topography as well as different surface chemical treatments were applied to study their influences on nasopharyngeal carcinoma cell (10-15 μm in diameter) migration in mimicked platforms over 15-hour of time-lapse imaging. By placing the pores at different distance from the edges of the trenches, pores with different trench sidewall exposures and effective sizes were generated. Pores right next to the trench sidewalls showed the highest cell traversing probability, most likely related to the larger surface contact area with cells along the sidewalls. Straight grating oriented perpendicular to trenches below the top layer increased cell traversing probability. Pore shape as well as pore size influenced the cell traversing probability and cells could not traverse through pores that were 6 μm or less in diameter, which is much smaller than the cell size. Trench depth of 15 μm could induce more cells to traverse through the porous membrane, while shallower trenches impeded cell traversing and longer time was needed for cells to traverse because 3 and 6 μm deep trenches were much smaller than cell size which required large cell deformation. Hydrophobic surface coating on the top layer and fibronectin in pores and trenches increased the cell traversing probability and reduced the pore size that cells could traverse from 8 to 6 μm, which indicated that cells could have larger deformation with certain surface coatings.

Targeting Epstein-Barr Virus in Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is consistently associated with Epstein-Barr virus (EBV) infection in regions in which it is endemic, including Southern China and Southeast Asia. The high mortality rates of NPC patients with advanced and recurrent disease highlight the urgent need for effective treatments. While recent genomic studies have revealed few druggable targets, the unique interaction between the EBV infection and host cells in NPC strongly implies that targeting EBV may be an efficient approach to cure this virus-associated cancer. Key features of EBV-associated NPC are the persistence of an episomal EBV genome and the requirement for multiple viral latent gene products to enable malignant transformation. Many translational studies have been conducted to exploit these unique features to develop pharmaceutical agents and therapeutic strategies that target EBV latent proteins and induce lytic reactivation in NPC. In particular, inhibitors of the EBV latent protein EBNA1 have been intensively explored, because of this protein's essential roles in maintaining EBV latency and viral genome replication in NPC cells. In addition, recent advances in chemical bioengineering are driving the development of therapeutic agents targeting the critical functional regions of EBNA1. Promising therapeutic effects of the resulting EBNA1-specific inhibitors have been shown in EBV-positive NPC tumors. The efficacy of multiple classes of EBV lytic inducers for NPC cytolytic therapy has also been long investigated. However, the lytic-induction efficiency of these compounds varies among different EBV-positive NPC models in a cell-context-dependent manner. In each tumor, NPC cells can evolve and acquire somatic changes to maintain EBV latency during cancer progression. Unfortunately, the poor understanding of the cellular mechanisms regulating EBV latency-to-lytic switching in NPC cells limits the clinical application of EBV cytolytic treatment. In this review, we discuss the potential approaches for improvement of the above-mentioned EBV-targeting strategies.

Differential Expression and Alternative Splicing of Transcripts Associated With Cisplatin-Induced Chemoresistance in Nasopharyngeal Carcinoma

Radiotherapy and adjuvant cisplatin (DDP) chemotherapy are standard administrations applied to treat nasopharyngeal carcinoma (NPC). However, the molecular changes and functions of DDP in NPC chemo-resistance remain poorly understood. In the present study, transcriptomic sequencing between 5-8F and 5-8F/DDP cells was performed to identify differential expression and alternative splicing (AS) characteristics in DDP-resistant NPC cells. Transcriptomic profiling identified 1,757 upregulated genes and 1,473 downregulated differentially expressed genes (DEGs). Bioinformatic analysis revealed that these DEGs were associated with or participated in important biological regulatory functions in NPC. Validation of 20 significant DEGs using quantitative real-time reverse transcription PCR showed that the expression patterns of 17 mRNAs were in accordance with the sequencing data. Intron retention was identified as the major AS event in chemoresistant cells. Furthermore, the expression level of matrix metalloproteinase 1 (MMP1), which was one of the most upregulated mRNAs in the chemoresistant cell lines, was significantly associated with the migration, invasion, and proliferation of NPC cells in vitro. Our study revealed that dysregulated genes and AS-mediated DDP chemoresistance might play important roles in NPC development and progression. Targeting aberrantly expressed genes might clarify the pathogenesis of NPC and contribute to developing new therapeutic strategies for NPC.

Mesenchymal stem/stromal cells-derived IL-6 promotes nasopharyngeal carcinoma growth and resistance to cisplatin via upregulating CD73 expression

Previous studies have implicated the important role of mesenchymal stem/stromal cells (MSCs) within tumor microenvironment (TME) in the pathogenesis and progression of nasopharyngeal carcinoma (NPC), but the potential mechanisms are still unclear. Herein, we showed that an elevated IL-6 level was positively correlated with elevated expression of CD73 in TME of NPC. NPC specimens with an IL-6highCD73high phenotype showed higher expression levels of gp80, gp130, p-STAT3, MMP-9 and α-SMA, and clinically, a poorer prognosis than those with an IL-6lowCD73low phenotype. We found that stimulation with conditioned media derived from IL-6 gene knocked out MSC (MSCIL6KO-CM) down-regulated the expression of CD73, IL-6, gp80, p-STAT3, and proliferative cell nuclear antigen (PCNA) in CNE-2 NPC cells. Meanwhile, NPC cells co-cultured with MSCIL6KO-CM were more sensitive to cisplatin than those co-cultured with MSC-CM. Additionally, MSC-derived IL-6 transcriptionally upregulated CD73 expression via activating STAT3 signaling pathway in NPC cells. In summary, our findings suggest that MSCs promote NPC progression and chemoresistance by upregulation of CD73 expression via activating STAT3 signaling pathway.