Nasopharyngeal carcinoma, with emphasis on its relationship to Epstein-Barr virus

Downregulation of KLF5 by EBER1 via the ERK signaling pathway in EBV-positive nasopharyngeal carcinoma cells: implications for latent EBV infection

Nasopharyngeal carcinoma (NPC) carcinogenesis and malignant transformation are intimately associated with Epstein-Barr virus (EBV) infection. A zinc-fingered transcription factor known as Krüppel-like factor 5 (KLF5) has been shown to be aberrantly expressed in a number of cancer types. However, little is known about the regulatory pathways and roles of KLF5 in EBV-positive NPC. Our study found that KLF5 expression was significantly lower in EBV-positive NPC than in EBV-negative NPC. Further investigation revealed that EBER1, which is encoded by EBV, down-regulates KLF5 via the extracellular signal-regulated kinase (ERK) signalling pathway. This down-regulation of KLF5 by EBER1 contributes to maintaining latent EBV infection in NPC. Furthermore, we uncovered the biological roles of KLF5 in NPC cells. Specifically, KLF5 may influence the cell cycle, prevent apoptosis, and encourage cell migration and proliferation - all of which have a generally pro-cancer impact. In conclusion, these findings offer novel strategies for EBV-positive NPC patients' antitumour treatment.

Long Non-Coding RNA Small Nucleolar RNA Host Gene 4 Induced by Transcription Factor SP1 Promoted the Progression of Nasopharyngeal Carcinoma Through Modulating microRNA-510-5p/Centromere Protein F Axis

Long non-coding RNAs (LncRNAs) are implicated with tumorigenesis and the development of nasopharyngeal carcinoma (NPC). Previous studies suggested that long non-coding RNA small nucleolar RNA host gene 4 (SNHG4) exerted oncogenic roles in various cancers. However, the function and molecular mechanism of SNHG4 in NPC have not been investigated. In our study, it was confirmed that the SNHG4 level was enriched in NPC tissues and cells. Functional assays indicated that SNHG4 depletion inhibited the proliferation and metastasis but promoted apoptosis of NPC cells. Furthermore, we identified miR-510-5p as a downstream gene of SNHG4 in NPC cells and SNHG4 upregulated CENPF expression by binding to miR-510-5p. Moreover, there was a positive (or negative) association between CENPF and SNHG4 (or miR-510-5p) expression in NPC. In addition, rescue experiments verified that CENPF overexpression or miR-510-5p silencing abrogated inhibitory effects on NPC tumorigenesis caused by SNHG4 deficiency. The study demonstrated that SNHG4 promoted NPC progression via miR-510-5p/CENPF axis, providing a novel potential therapeutic target for NPC treatments.

Vulvar squamous cell carcinoma arising on human papillomavirus-independent precursors mimicking high-grade squamous intra-epithelial lesion: a distinct and highly recurrent subtype of vulvar cancer

AIMS

Each category of vulvar squamous cell carcinoma (VSCC), human papillomavirus (HPV)-associated and HPV-independent, arises on a specific intra-epithelial precursor: high-grade squamous intra-epithelial lesions (HSIL) and differentiated vulvar intra-epithelial neoplasia (dVIN), respectively. However, a subset of HPV-independent VSCC arises on an intra-epithelial precursor closely mimicking HSIL. We aimed to explore the clinicopathological features of the HPV-independent tumours with HSIL-like lesions and compare them with HPV-independent VSCC with dVIN and HPV-associated tumours with HSIL.

METHODS AND RESULTS

We retrospectively identified 105 cases of surgically treated VSCC with adjacent intra-epithelial precursors. The cases were classified into three groups based on the HPV status and the adjacent precursor identified: (i) HPV-associated VSCC with HSIL (n = 26), (ii) HPV-independent VSCC with dVIN lesions (n = 54) and (iii) HPV-independent VSCC with HSIL-like lesions (n = 25). We analysed the histological and clinical features including the recurrence-free survival and disease-specific survival in the three groups. Patients with HPV-independent VSCC with HSIL-like lesions and with dVIN were older than patients with HPV-associated VSCC (76 and 77 versus 66 years, respectively, P < 0.001). HPV-independent VSCC with HSIL-like lesions recurred more frequently [hazard ratio (HR) = 3.87; P < 0.001] than HPV-independent VSCC with dVIN (HR = 2.27; P = 0.1) and HPV-associated VSCC (HR = 1). In the multivariate analysis, HPV-independent VSCC with HSIL-like lesions remained significant for recurrence. No differences in disease-specific survival were observed between the three groups.

CONCLUSIONS

Even though VSCC with HSIL-like lesions are not associated with higher mortality, they are more likely to recur and might benefit from more intensive treatment strategies and closer surveillance after treatment.

It Takes Two to Tango: A Review of Oncogenic Virus and Host Microbiome Associated Inflammation in Head and Neck Cancer

Simple Summary

Certain viruses, specifically, human papillomavirus (HPV) and Epstein–Barr virus (EBV), have been linked with the development of head and neck cancer. In this study, we review the mechanisms by which (these) viruses lead to cellular transformation and a chronic inflammatory state. Given that the head and neck host a rich microbiome (which itself is intrinsically linked to inflammation), we scrutinize the literature to highlight the interplay between viruses, cellular transformation, inflammation, and the local host microbiome in head and neck cancer.

Abstract

While the two primary risk factors for head and neck squamous cell carcinoma (HNSCC) are alcohol and tobacco, viruses account for an important and significant upward trend in HNSCC incidence. Human papillomavirus (HPV) is the causative agent for a subset of oropharyngeal squamous cell carcinoma (OPSCC)—a cancer that is impacting a rapidly growing group of typically middle-aged non-smoking white males. While HPV is a ubiquitously present (with about 1% of the population having high-risk oral HPV infection at any one time), less than 1% of those infected with high-risk strains develop OPSCC—suggesting that additional cofactors or coinfections may be required. Epstein–Barr virus (EBV) is a similarly ubiquitous virus that is strongly linked to nasopharyngeal carcinoma (NPC). Both of these viruses cause cellular transformation and chronic inflammation. While dysbiosis of the human microbiome has been associated with similar chronic inflammation and the pathogenesis of mucosal diseases (including OPSCC and NPC), a significant knowledge gap remains in understanding the role of bacterial-viral interactions in the initiation, development, and progression of head and neck cancers. In this review, we utilize the known associations of HPV with OPSCC and EBV with NPC to investigate these interactions. We thoroughly review the literature and highlight how perturbations of the pharyngeal microbiome may impact host-microbiome-tumor-viral interactions—leading to tumor growth.

Paraneoplastic dermatomyositis revealing undifferentiated nasopharyngeal carcinoma at early stage: a case report

Context

Dermatomyositis is a rare autoimmune disease characterized by noninfectious inflammatory damage of skin and predominant muscles in the belts. It is believed to be associated with about 1 in 1000 cases of nasopharyngeal carcinoma. This association has been described for locally advanced stages II and III nasopharyngeal carcinoma. It has rarely been described in the early stages (stage I).

Case presentation

A 65-year-old Moroccan patient residing in Casablanca, with no particular history was referred to the Mohamed VI Center for the treatment of cancers of the University Hospital Center IBN ROCHD in Casablanca, for treatment of nasopharyngeal cancer. He was admitted in poor general condition, performance status 3, with erythema on the face, neck, and extremities. The diagnosis of paraneoplastic dermatomyositis was made owing to progressive muscle weakness and elevation of muscle enzymes associated with the typical rash of the face and hands. He received corticosteroid therapy and then radiotherapy to the nasopharynx with good clinical outcome, disappearance of skin lesions, and recovery of muscle strength.

Conclusions

We report this case of dermatomyositis in early-stage nasopharyngeal carcinoma, which is a rarely described entity. Rapid treatment of dermatomyositis improved the patient’s quality of life and enabled him to support specific cancer treatments. This can be used as an element of early diagnosis and monitoring after treatment.

The evolution of bone marrow signal changes at the skull base in nasopharyngeal carcinoma patients treated with radiation therapy

BACKGROUND

Clival infiltration is frequently seen in nasopharyngeal carcinoma (NPC) and the resultant bone marrow signal changes (BMSC) can persist even after complete tumor response to the radiation therapy (RT). The differentiation of those residual BMSC from recurrent/persistent disease may be challenging. We performed serial analysis of the clival BMSC after RT, to define an expected temporal evolution of those signal changes during the follow-up.

MATERIALS AND METHODS

Serial MRI studies of 50 NPC patients (with or without initial clival infiltration) who had undergone RT were retrospectively examined. Abnormal clival BMSC and contrast enhancement (CE) were evaluated on each follow-up scan. Duration of BMSC/CE was correlated with the degree of baseline clival involvement (BCID), RT dose, and primary mass volume (PMV).

RESULTS

Clival BMSC persisted without any evidence of recurrence, for a mean of 66.5 (max. 137) months (with accompanying CE for up to 125 months) in 26 patients with clival infiltration at diagnosis. Duration of BMSC and CE showed statistical correlations with PMW (p < 0.05), but not with RT dose or BCID. The rate of recurrence in clivus was 14%. New clival lesions that occurred within the first 12 months after RT (in six patients) did not develop recurrence suggesting radiation osteitis (12%).

CONCLUSION

After RT, residual clival medullary signal change/enhancement is seen in most NPC patients and can persist even years without recurrence.

PACE4 Expression is a Novel Independent Prognostic Factor in Nasopharyngeal Carcinoma

Background

Paired basic amino acid-cleaving enzyme 4 (PACE4) belongs to the family of proprotein convertase and is essential for tumor progression, whereas its role in cancer remains controversial and little is known about its role in nasopharyngeal carcinoma (NPC). The aim of this study was to examine if the expression of PACE4 is a prognostic biomarker for patients with NPC.

Methods

Immunofluorescence (IF) and immunohistochemistry (IHC) were used to analyze PACE4 expression in NPC cell line CNE1 and 172 clinicopathologically characterized NPC tissues. The data were analyzed by Chi-square test, Kaplan–Meier plots, and Cox proportional hazards regression model.

Results

IF and IHC staining results showed that PACE4 was mainly located in the cytoplasm of NPC cell line (CNE1) and NPC tissues. Expression of PACE4 was observed in 46/172 (26.7%) of NPC tissues. Further analysis showed that expression of PACE4 was positively associated with late N stage, distant metastasis, and late clinical stage (P<0.05). High expression of PACE4 predicted shorter 5-year overall survival of patients with NPC, especially for the patients in advanced stage (32.7% vs 77.3%, P<0.001). Furthermore, multivariate analysis showed that PACE4 expression may serve as a potential prognostic factor for NPC.

Conclusion

Our results suggest that PACE4 may play a crucial role in tumor progression and may serve as a valuable prognostic biomarker for patients with NPC.

MRI of benign hyperplasia in the nasopharynx: is there an association with Epstein-Barr virus?

AIM

To evaluate whether there is an association between persistently positive plasma Epstein-Barr virus (EBV) DNA and the presence and the change in benign hyperplasia.

MATERIALS AND METHODS

One hundred and seventeen participants with positive-plasma EBV-DNA, but without NPC from previous nasopharyngeal carcinoma (NPC) screening, underwent follow-up magnetic resonance imaging (MRI) and plasma EBV-DNA after 2 years. Logistic regression was used to analyse associations between MRI (benign hyperplasia on the follow-up MRI and change from 2 years earlier), and plasma EBV-DNA, smoking, and age.

RESULTS

At follow-up, EBV-DNA positivity and smoking were independent parameters for the presence of benign hyperplasia (p=0.027 and 0.023 respectively). Compared with participants in whom EBV-DNA became negative (n=44/117 37.6%), those in whom EBV-DNA remained positive (n=73/117 62.4%) had a greater risk of benign hyperplasia developing (previous MRI normal), being stable or processing (52/73 71.2% versus 18/44 40.9%; p=0.001).

CONCLUSION

These results suggest a potential link between benign hyperplasia on MRI and the EBV. As EBV contributes to NPC oncogenesis, future MRI research is warranted to determine if persistent benign hyperplasia is a risk marker for development of NPC.

Downregulation of ABI2 expression by EBV-miR-BART13-3p induces epithelial-mesenchymal transition of nasopharyngeal carcinoma cells through upregulation of c-JUN/SLUG signaling

Existing evidence has shown that circulating Epstein-Barr virus (EBV)-miR-BART13-3p is highly expressed in plasma of nasopharyngeal carcinoma (NPC) patients, especially among patients with advanced diseases. However, the exact role that EBV-miR-BART13-3p plays in the development of NPC remains poorly understood. Here we show that up-regulated expression of EBV-miR-BART13-3p leads to increased capacity in migration and invasion of NPC cells in vitro and causes tumor metastasis in vivo. Furthermore, we find that EBV-miR-BART13-3p directly targets ABI2, known as a tumor suppressor and a cell migration inhibitor, drives epithelial-mesenchymal transition (EMT) by activating c-JUN/SLUG signaling pathway. Silencing ABI2 shows similar effects to overexpression of EBV-miR-BART13-3p, whereas reconstitution of ABI2 resulted in a phenotypic reversion, highlighting the role of ABI2 in EBV-miR-BART13-3p-driven metastasis in NPC. Besides, expression levels of ABI2 in NPC tissue samples correlate with N stages of NPC patients. Taken together, these results suggest a novel mechanism by which ABI2 downregulation by EBV-miR-BART13-3p promotes EMT and metastasis of NPC via upregulating c-JUN/SLUG signaling pathway.

Differences in cancer gene copy number alterations between Epstein-Barr virus-positive and Epstein-Barr virus-negative nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal carcinoma (NPC) treatment is mainly based on clinical staging. We hypothesize that better understanding of the molecular heterogeneity of NPC can aid in better treatment decisions. Therefore, the purpose of this study was to present our exploration of cancer gene copy-number alterations (CNAs) of Epstein-Barr virus (EBV)-positive and EBV-negative NPC.

METHODS

Multiplex ligation-dependent probe amplification was applied to detect CNAs of 36 cancer genes (n = 103). Correlation between CNAs, clinicopathological features, and survival were examined.

RESULTS

The CNAs occurred significantly more in EBV-negative NPC, with PIK3CA and MCCC1 (P < .001) gain/amplification occurring more frequently. Gain/amplification of cyclin-L1 (CCNL1) and PTK2 (P < .001) predict worse disease-free survival (DFS) in EBV-positive NPC.

CONCLUSION

The EBV-positive and EBV-negative NPC show some similarities in cancer gene CNAs suggesting a common pathogenic route but also important differences possibly indicating divergence in oncogenesis. Copy number gain/amplification of CCNL1 and PTK2 are possibly good predictors of survival in EBV-positive NPC.

MicroRNA-Related Polymorphisms in Infectious Diseases-Tiny Changes With a Huge Impact on Viral Infections and Potential Clinical Applications

MicroRNAs (miRNAs) are single-stranded sequences of non-coding RNA with approximately 22 nucleotides that act posttranscriptionally on gene expression. miRNAs are important gene regulators in physiological contexts, but they also impact the pathogenesis of various diseases. The role of miRNAs in viral infections has been explored by different authors in both population-based as well as in functional studies. However, the effect of miRNA polymorphisms on the susceptibility to viral infections and on the clinical course of these diseases is still an emerging topic. Thus, this review will compile and organize the findings described in studies that evaluated the effects of genetic variations on miRNA genes and on their binding sites, in the context of human viral diseases. In addition to discussing the basic aspects of miRNAs biology, we will cover the studies that investigated miRNA polymorphisms in infections caused by hepatitis B virus, hepatitis C virus, human immunodeficiency virus, Epstein–Barr virus, and human papillomavirus. Finally, emerging topics concerning the importance of miRNA genetic variants will be presented, focusing on the context of viral infectious diseases.

Prognostic value of pre-treatment 18F-FDG PET uptake for nasopharyngeal carcinoma

PURPOSE

To evaluate the prognostic value of maximal standardized uptake values (SUVmax) from serial fluor-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in patients with nasopharyngeal carcinoma (NPC).

MATERIALS AND METHODS

Fifty-two patients with NPC who underwent 18F-FDG PET/CT scan before radiotherapy with/without chemotherapy were reviewed retrospectively. Twenty-seven patients (52%) were applied 3-D conformal radiotherapy and 25 patients (48%) applied intensity-modulated radiotherapy (IMRT). Fourteen (27%) patients were given neoadjuvant chemotherapy and forty-four (84.6%) patients were given concomitant and adjuvant chemotherapy.

RESULTS

Median follow-up time was 34 months (range 5.6-66.4 months). Forty-four (84.6%) patients were alive at last follow-up and eight (15.4%) had died. The best cut-off value of the SUVmax for the primary tumor site (SUVmax-PT) was 13 and 9 for the lymph nodes (SUVmax-LN). Patients with SUVmax-PT ≥ 13.0 and SUVmax-LN ≥ 9 had a significantly higher risk for the development of the distant metastases (p = 0.044 and p = 0.038). DFS was affected in patients with SUVmax-PT ≥ 13 (log rank χ 2 = 2.54, p = 0.017) and was significantly lower in patients with SUVmax-LN ≥ 9 for the lymph nodes (log rank χ 2 = 5.81, p = 0.013). OS was not affected by SUV levels. A multivariate Cox proportional hazard model of DFS included age (≥ 40), SUVmax-LN (< 9), T stage (T1-2) and neoadjuvant chemotherapy are significantly better prognosis for the DFS.

CONCLUSION

18F-FDG PET/CT uptake before treatment, as determined by SUVmax, may be a valuable tool to evaluate prognosis in NPC patients.

Molecular profile of nasopharyngeal carcinoma: analysing tumour suppressor gene promoter hypermethylation by multiplex ligation-dependent probe amplification

Aims

To assess differences in methylation profiles, and thus pathogenesis, between Epstein-Barr virus (EBV)-positive and negative nasopharyngeal carcinomas (NPCs). Also, promoter hypermethylation is a common phenomenon in early carcinogenesis to inactivate tumour suppressor genes. Since epigenetic changes are reversible, the therapeutic application of methylation inhibitors could provide treatment options.

Methods

We evaluated promoter hypermethylation profiles of 22 common tumour suppressor genes in 108 NPCs using methylation-specific multiplex ligation-dependent probe amplification. Correlation between methylation, clinicopathological features (including EBV) and survival was examined. Cluster analysis was also performed.

Results

Hypermethylation of RASSF1A and ESR1 was significantly more frequent in EBV-positive NPC, while hypermethylation of DAPK1 was more frequent in EBV-negative NPC. In logistic regression, age, with EBV-positive NPC occurring at earlier age, and RASSF1, with RASSF1 hypermethylation being more frequent in EBV-positive NPC, remained significant. In EBV-positive NPC, hypermethylation of RASSF1A predicted worse overall survival (OS) (HR 3.058,95% CI 1.027 to 9.107). In EBV-negative NPC, hypermethylated adenomatous polyposis coli (APC) was a predictor of poor disease-free survival (DFS) (HR 6.868, 95% CI 2.142 to 22.022).

Conclusion

There are important epigenetic differences between EBV-negative and EBV-positive NPCs, with EBV-negative NPC having a more similar hypermethylation profile to other head and neck squamous cell carcinomas than EBV-positive NPC. Hypermethylation of RASSF1A might contribute to worse OS in EBV-positive NPC, and may be an important event in the pathogenesis of EBV-infected NPC. Hypermethylation of APC might contribute to worse DFS in EBV-negative NPC.

CORRELATION BETWEEN INTRACELLULAR HEAT SHOCK PROTEIN 70 EXPRESSION AND CERVICAL LYMPH NODES ENLARGEMENT IN NASOPHARYNGEAL CARCINOMA

Tumor growth and metastasis in NPC patients suspected role of several molecular biomarkers that have been identified in tumor specimens of patients with NPC. Recent research states intracellular Hsp70 is a stress protein that is a main factor for the growth, invasion and metastasis of NPC. The purpose of this study is to analyze intracellular Hsp70 protein expression of NPC patients which correlate with staging of NPC as clinical manifestation. This study used cross sectional design. In this study, formalin-fixed paraffin-embedded biopsy specimens were obtained from 18 NPCs with all of histopathology and clinically divided into N0, N1, N2, N3. The expression of intracellular Hsp70 was obtained with immunohistochemistry using monoclonal antibody Anti Human Hsp70 antibodi from Santa Cruz Biotechnology, California, USA. Assessment of the staining was performed with Remmele methode by Histopathologies doctor Consultant. The Spearman’s test was used to determine the relationship between expression of intracellular Hsp70 protein and enlargement cervical nodul of NPC. Statistical significance was defined as p <0,05. There were 18 patients NPC patients that met the inclusion and exclusion criteria. Showed negative intracellular Hsp70 expression by 16,67% for all sample in which consist 1 patient of N0, 1 patient of N1, 1 patient of N2, 0 patient of N3. Followed by 27,78% mild positive intracellular Hsp70 expression which consist 0 patient of N0, 2 patients of N1, 0 patient of N2, 3 patients of N3. Followed by 44,44% moderate positive intracellular Hsp70 expression which consist 0 patient of N0, 0 patient of N1, 1 patient of N2, 9 patients of N3. Followed by 11,11% strongly positive intracellular Hsp70 expression which consist 0 patient of N0, 0 patient of N1, 0 patient of N2, 2 patients of N3. Spearman test results test scores p = 0.01 with a correlation coefficient 0.606. Correlation of intracellular Hsp70 protein expression with enlargement cervical nodul of lymphe (N0, N1, N2, N3) in patients with NPC showed significant (p<0.05). In conclusion, there was correlation between increase of the intacellular Hsp70 expression and enlargement cervical nodul of lymphe in nasopharyngeal carcinoma.

Prevalence and significance of plasma Epstein-Barr Virus DNA level in nasopharyngeal carcinoma

Epstein-Barr virus (EBV) DNA has been recognized as a promising tumor marker for nasopharyngeal carcinoma (NPC). This study aims to demonstrate the prevalence of plasma EBV DNA and its temporal correlation with treatment outcomes in the modern era. A total of 204 patients with Stage I-IVB NPC treated with intensity-modulated radiotherapy (IMRT) were enrolled. Quantitative plasma EBV DNA measurement was performed before treatment (pre-IMRT), on the fifth week of radiation (mid-IMRT), at 3 months after radiation (post-IMRT), then every 6 months until disease relapse. Progression-free survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier method. Plasma EBV DNA was detected in 110 patients (53.9%), with a median pre-IMRT EBV DNA level of 8005 copies/ml. Significant correlation was noted between pre-IMRT EBV DNA level and disease stage, but not between pre-IMRT EBV DNA level and World Health Organization classification. With a median follow-up time of 35.1 months, the 3-year PFS and OS rates were higher in the group with undetectable pre-IMRT EBV DNA level compared with in the group in which it was detectable. When classified according to disease stage and pre-IMRT EBV DNA, patients with early disease and detectable pre-IMRT EBV DNA experienced poorer survival than those with locally advanced disease and undetectable pre-IMRT EBV DNA. According to the dynamic changes in EBV DNA level between pre-IMRT and mid/post IMRT, survival was significantly higher in patients who achieved an undetectable level following treatment. On multivariate analysis, post-IMRT EBV DNA level was the strongest predictor of all treatment outcomes (P < 0.001). Our study demonstrated the clinical significance of the plasma EBV DNA level at specific time points, as well as of the dynamic changes in the EBV DNA level. Disappearance of plasma EBV DNA after treatment was associated with better survival.

Virus-associated neoplasms of the nasopharynx and sinonasal tract: diagnostic problems

A significant fraction of nasopharyngeal and sinonasal tumors are associated with Epstein-Barr virus (EBV) or human papillomavirus (HPV). Nasopharyngeal carcinoma (NPC) and extranodal NK/T-cell lymphoma harbor EBV in practically all cases, although a small proportion of cases of the former harbor HPV. Sinonasal inverted papillomas harbor HPV in about 25% of cases. Sinonasal squamous cell carcinomas harbor transcriptionally active HPV in about 20% of cases, and limited data suggest that this subset has a better prognosis than the HPV-negative subset. This review addresses the diagnostic issues of the EBV-associated tumors. Difficulties in diagnosis of NPC may be encountered when there are prominent crush artifacts, many admixed lymphoid cells masking the neoplastic cells, or numerous interspersed granulomas, whereas benign cellular components (epithelial crypts and germinal centers) and reactive lymphoid hyperplasia can potentially be mistaken for NPC. Immunostaining for pan-cytokeratin and/or in situ hybridization for EBER can help in confirming or refuting a diagnosis of NPC. The main diagnostic problem of extranodal NK/T-cell lymphoma is recognition of the neoplastic nature of those examples predominated by small cells or showing a mixture of cells. The identification of a destructive infiltrate (dense expansile infiltrate; angiocentric growth) and definite cytologic atypia (clear cells; many medium-sized cells) would favor a diagnosis of lymphoma, which can be supported by immunohistochemistry (most commonly CD3+, CD5-, CD56+) and in situ hybridization for EBER. In conclusion, among nasopharyngeal and sinonasal neoplasms, demonstration of EBV may aid in diagnosis, particularly NPC and extranodal NK/T-cell lymphoma. Demonstration of HPV does not have a role yet in diagnosis, although this may change in the future.

The Role of Gammaherpesviruses in Cancer Pathogenesis

Worldwide, one fifth of cancers in the population are associated with viral infections. Among them, gammaherpesvirus, specifically HHV4 (EBV) and HHV8 (KSHV), are two oncogenic viral agents associated with a large number of human malignancies. In this review, we summarize the current understanding of the molecular mechanisms related to EBV and KSHV infection and their ability to induce cellular transformation. We describe their strategies for manipulating major cellular systems through the utilization of cell cycle, apoptosis, immune modulation, epigenetic modification, and altered signal transduction pathways, including NF-kB, Notch, Wnt, MAPK, TLR, etc. We also discuss the important EBV latent antigens, namely EBNA1, EBNA2, EBNA3’s and LMP’s, which are important for targeting these major cellular pathways. KSHV infection progresses through the engagement of the activities of the major latent proteins LANA, v-FLIP and v-Cyclin, and the lytic replication and transcription activator (RTA). This review is a current, comprehensive approach that describes an in-depth understanding of gammaherpes viral encoded gene manipulation of the host system through targeting important biological processes in viral-associated cancers.

Evaluation of serum granulysin as a potential biomarker for nasopharyngeal carcinoma

BACKGROUND

Granulysin (GNLY) is excreted from cytotoxic T lymphocytes and natural killer cells, and plays an important role in antitumor immunity. However, few studies have estimated serum GNLY concentrations in patients with nasopharyngeal carcinoma (NPC). We evaluated GNLY as a potential biomarker for NPC.

METHODS

Serum GNLY concentrations were measured in blood samples taken from 98 NPC patients, 56 nasopharyngitis (NPT) patients, and 99 healthy subjects. The clinical relevance of GNLY in NPC was also investigated. We also assessed the association between serum GNLY and serum immunoglobulin A antibodies against the Epstein-Barr virus (EBV) viral capsid antigen (VCA-IgA) and EBV DNA.

RESULTS

Serum GNLY levels were significantly lower in NPC patients and significantly higher in nasopharyngitis patients compared to healthy controls. Thus, serum GNLY performs well as a biomarker for distinguishing between NPC and NPT. The serum GNLY concentration is elevated with corresponding increases in clinical stage and shows a significant correlation with VCA-IgA and EBV DNA concentration.

CONCLUSIONS

Serum GNLY is closely associated with the clinical characteristics of NPC and may be a potential biomarker for NPC.

Sinonasal small round blue cell tumors: An approach to diagnosis

The differential diagnosis for small round cell tumors in the sinonasal tract is diverse and as the body of literature documenting not only uncommon presentations but also availability of ancillary studies grows, so does the need for a reminder to take a conservative and thorough approach before rendering a diagnosis. Small tissue samples are particularly problematic, with limitations that include volume of tumor cells available for studies, lack of architectural context and a non-specific gross description. Incorporation of patient history and presentation, radiologic findings, clinical impression and concurrent studies often guide the course of studies performed by the pathologist. If these are non-specific, the pathologist may need to perform ancillary studies, including a broad panel of immunohistochemical stains and molecular studies. If tissue is limited, a precise classification may not be achievable. Although the expectation to render a definitive diagnosis is high, the pathologist should never feel compelled to go further with a diagnosis than the tissue itself supports.

Disease control and toxicity outcomes for T4 carcinoma of the nasopharynx treated with intensity-modulated radiotherapy

BACKGROUND

Treatment of T4 nasopharyngeal carcinoma (NPC) is challenging because of the proximity of the tumor to the central nervous system. The purpose of this study was to present our evaluation of disease control and toxicity outcomes for patients with T4 NPC treated with intensity-modulated radiation therapy (IMRT) and chemotherapy.

METHODS

The medical records of 66 patients with T4 NPC treated from 2002 to 2012 with IMRT were reviewed. Endpoints included tumor control and toxicity outcomes (Common Terminology Criteria for Adverse Events [CTCAE v4.0]).

RESULTS

Median follow-up was 38 months. Five-year rates of locoregional control, distant metastasis-free survival, progression-free survival (PFS), and overall survival (OS) were 80%, 62%, 57%, and 69%, respectively. Nodal involvement was associated with worse PFS (p = .015). Gross target volume (GTV) volume >100 cm and planning target volume (PTV) volume >400 cm were associated with worse OS (p = .038 and p = .004, respectively). Four patients had significant cognitive impairment, and 9 had MRI evidence of brain necrosis.

CONCLUSION

For patients with T4 NPC treated with IMRT and chemotherapy, survival and locoregional disease control rates have improved; however, late treatment toxicity remains a concern. © 2015 Wiley Periodicals, Inc. Head Neck 38: E925-E933, 2016.

Polymorphisms of NFκB1 and IκBα and Their Synergistic Effect on Nasopharyngeal Carcinoma Susceptibility

Nasopharyngeal carcinoma (NPC) is a multifactoral and polygenic disease with high prevalence in Southeast Asia and Southern China. Environmental factors and genetic susceptibility play important roles in NPC pathogenesis. In the present study, we tested the hypothesis that single nucleotide polymorphisms (SNPs) in nuclear factor-kappa B (NFκB) and its inhibitor (IκBα) conferred consistent risks for NPC. Four putatively functional SNPs (NFκB1: rs28362491del>ins ATTG; NFκB2: rs12769316G>A; IκBα: rs2233406C>T and rs696G>A) were analyzed to evaluate their associations with NPC risk in total 1590 NPC cases and 1979 cancer-free controls. We found that the rs28362491 insATTG variants (ins/del + ins/ins) in NFκB1 conferred an increased risk of NPC (odds ratio [OR] = 1.30, 95% confidence interval [CI] = 1.09–1.55, and P = 2.80 × 10⁻³) compared with the del/del homozygous genotype. The rs696AA variant in IκBα had an increased risk of NPC (OR = 1.41, 95% CI = 1.20–1.66, and P = 2.28 × 10⁻⁵) by decreasing IκBα expression due to the modulation of microRNA hsa-miR-449a. Furthermore, both adverse genotypes of NFκB/IκBα and their interaction also exerted an increased risk on NPC. Taken together, Our findings indicated that genetic variants in NFκB1 (rs28362491del>ins ATTG) and IκBα (rs696G>A) and their synergistic effect might contribute to NPC predisposition.

Polymorphism in mature microRNA-608 sequence is associated with an increased risk of nasopharyngeal carcinoma

Accumulative evidences indicated that microRNAs (miRNAs) can function as tumor suppressors and oncogenes, in which genetic variations are implicated in various cancer susceptibilities. However, it remains unclear whether single nucleotide polymorphisms (SNPs) in mature miRNA sequence alter nasopharyngeal carcinoma (NPC) susceptibility. In this study, we analyzed associations between eight SNPs in miRNA mature sequences (i.e., rs3746444T>C in hsa-mir-499, rs4919510C>G in hsa-mir-608, rs13299349G>A in hsa-mir-3152, rs12220909G>C in hsa-mir-4293, rs2168518G>A in hsa-mir-4513, rs8078913T>C in hsa-mir-4520a, rs11237828T>C in hsa-mir-5579, and rs9295535T>C in hsa-mir-5689) and NPC susceptibility in southern China with 906 NPC cases and 1072 cancer-free controls, and validated the significant findings in eastern China with 684 cases and 907 healthy controls. Functional assays were further performed to identify the biological effects of these polymorphisms. We found that rs4919510C>G polymorphism showed a consistent association with NPC risk in southern China (GC+GG versus CC genotype, odds ratio [OR]=1.36, 95% confidence interval [CI]=1.10-1.70) and eastern China (GC+GG versus CC: OR=1.37, 95% CI=1.08-1.74). After the two populations were merged, the ORs and 95% CI were 1.38 and 1.18 to 1.62, respectively. Moreover, the rs4919510C>G adverse genotypes significantly interacted with Epstein-Barr virus (EBV) infection on increasing NPC risk (P=0.001). The functional assay further showed that the CNE-2 cell lines that transfected with miR-608-rs4919510G allele expression vector exerted more colony number formations than cell lines that transfected with miR-608-rs4919510C allele expression vector (P=0.001). These data suggested that rs4919510C>G of miR-608 may be a susceptible biomarker of NPC in China.

Circulating Epstein-Barr virus microRNAs miR-BART7 and miR-BART13 as biomarkers for nasopharyngeal carcinoma diagnosis and treatment

More than 75% of nasopharyngeal carcinoma (NPC) patients have already developed local or regional spread at diagnosis, which hampers effective treatment and results in a poor prognosis. It is essential to characterize more sensitive and specific biomarkers for screening of high risk individuals and assessment of NPC treatment effectiveness. NPC is an Epstein-Barr virus (EBV) associated tumor in which only a few viral proteins but more than 20 BamHI A rightward transcripts (BART) microRNAs are detected, at abundant levels. We hypothesized that these BART microRNAs may be novel biomarkers for NPC. Systematic analysis of EBV BART microRNA expression profiles in EBV latently infected Mutu I and Mutu III cell lines, EBV-harboring NPC and noncancerous NP cells found that miR-BART3, miR-BART7 and miR-BART13 microRNAs are highly expressed and regularly secreted into the extracellular environment of NPC cells. These BART microRNAs were evaluated for used as potential NPC biomarkers. Analysis of plasma specimens obtained from NPC patients (n = 89), and healthy (n = 28) and non-NPC tumor patient controls (n = 18) found levels of both miR-BART7 and miR-BART13, but not miR-BART3, to be distinctly presence among NPC patients, with elevated levels being particularly apparent among patients with advanced disease. Receiver operating characteristic curve analysis combining miR-BART7 and miR-BART13 levels produces a 90% predictive value for the presence of NPC. Analysis of 41 NPC patients before and after radiotherapy showed that miR-BART7 and miR-BART13, but not miR-BART3, were diminished after treatment. These results indicate that EBV microRNAs, miR-BART7 and miR-BART13, may constitute useful new serological biomarkers for diagnosis of NPC and prediction of treatment efficacy.

Functional expression of chloride channels and their roles in the cell cycle and cell proliferation in highly differentiated nasopharyngeal carcinoma cells

We previously demonstrated that the growth of the poorly differentiated nasopharyngeal carcinoma cells (CNE‐2Z) was more dependent on the activities of volume‐activated chloride channels than that of the normal nasopharyngeal epithelial cells (NP69‐SV40T). However, the activities and roles of such volume‐activated chloride channels in highly differentiated nasopharyngeal carcinoma cells (CNE‐1) are not clarified. In this study, it was found that a volume‐activated chloride current and a regulatory volume decrease (RVD) were induced by 47% hypotonic challenges. The current density and the capacity of RVD in the highly differentiated CNE‐1 cells were lower than those in the poorly differentiated CNE‐2Z cells, and higher than those in the normal cells (NP69‐SV40T). The chloride channel blockers, 5‐nitro‐2‐(3‐phenylpropylamino) benzoic acid (NPPB) and tamoxifen inhibited the current and RVD. Depletion of intracellular Cl⁻ abolished the RVD. The chloride channel blockers reversibly inhibited cell proliferation in a concentration‐ and time‐dependent manner, and arrested cells at the G0/G1 phases, but did not change cell viability. The sensitivity of the three cell lines to the chloride channel blockers was different, with the highest in poorly differentiated cells (CNE‐2Z) and the lowest in the normal cells (NP69‐SV40T). ClC‐3 proteins were expressed in the three cells and distributed inside the cells as well as on the cell membrane. In conclusion, the highly differentiated nasopharyngeal carcinoma CNE‐1 cells functionally expressed the volume‐activated chloride channels, which may play important roles in controlling cell proliferation through modulating the cell cycle, and may be associated with cell differentiation. Chloride channels may be a potential target of anticancer therapy.

In this paper, we demonstrated that the volume‐activated chloride channels were involved in regulating CNE‐1 cells proliferation and cell cycle progress. Thus, volume‐activated chloride channels may be a potential target of anticancer therapy.

Expression of Epstein-Barr virus-encoded latent membrane protein (LMP-1), p16 and p53 proteins in nonendemic nasopharyngeal carcinoma (NPC): a clinicopathological study

BACKGROUND AND AIMS

Although the latent membrane protein type 1 (LMP1) is frequently expressed in Epstein-Barr virus (EBV) malignancies, its contribution to the pathogenesis of nasopharyngeal carcinoma (NPC) is not fully defined. LMP1 functions as a viral mimic of the TNFR family member engaging a number of signaling pathways that induce morphological and phenotypic alterations. This study aimed to investigate the LMP1 expression and EBV infection in relation to clinical outcome and survival in a series of Mexican NPC patients. We also studied expression of p16 and p53 proteins.

METHODS

We analyzed in 25 tumor specimens the expression of LMP1, p16 and p53 by immunohistochemistry (IHC) and EBV presence by IHC/in situ hybridization. Differences in clinical outcome and survival in relation to protein expression were correlated through χ(2) statistics and Kaplan-Meier survival curves.

RESULTS

Our results showed a rate of 92% (23/25) of EBV infection. The expressions of LMP-1, p16 and p53 proteins were 40.0, 44.0 and 40.0%, respectively. LMP-1 immunoexpression was more common in older patients (>50 vs. <50 years old, p = 0.02) and with parapharyngeal space invasion (p = 0.02). The presence of metastatic disease at diagnosis (p = 0.03), distant recurrence disease (p = 0.006) and shorter distance recurrence-free survival (p = 0.05) was associated with lack of p16.

CONCLUSIONS

In our series, EBV infection rates are particularly high for nonendemic NPC, although without a statistically significant difference in overall survival, LMP1 and p16 expression was correlated with poorer clinical prognosis. Probably, LMP1 and p16 detection identify a worse clinical prognosis in NPC patient subgroup.

Chemoprevention of head and neck squamous cell carcinoma through inhibition of NF-κB signaling

Nuclear factor-kappa B (NF-κB) transcription factors regulate cellular processes such as inflammation and cell survival. The NF-κB pathway is often activated with development and progression of head and neck squamous cell carcinoma (HNSCC). As such, NF-κB represents an attractive target for chemoprevention. HNSCC involves progression of lesions from premalignant to malignant, providing a window of opportunity for intervention with chemopreventive agents. Appropriate chemopreventive agents should be inexpensive, nontoxic, and target important pathways involved in the development of HNSCC. Several such agents that inhibit the NF-κB pathway have been investigated in HNSCC. Retinoids have been studied most extensively but have shown limited potential in human trials. Epidermal growth factor receptor inhibitors and PI3K-mTOR inhibitors may benefit a subset of patients. Other agents such as green tea extract and curcumin are appealing because they are generally regarded as safe. In contrast, there is evidence that Vitamin E supplementation may actually increase mortality of cancer patients. Repurposed drugs such as cyclooxygenase (COX) inhibitors and antidiabetic drugs are an emerging area of interest. Future research to develop agents with lower toxicity and higher specificity for the NF-κB pathway, and to target these therapies to individual patient genetic signatures should help to increase the utility of chemoprevention in HSNCC.

Uncommon presentation of a benign nasopharyngeal mass in an adolescent: comprehensive review of pediatric nasopharyngeal masses

Nasopharyngeal masses in the pediatric population are quite rare, and the majority of these are benign. In adolescent boys, there should be a high index of suspicion for juvenile nasopharyngeal angiofibromas. When malignant, the most common lesions encountered are rhabdomyosarcomas, carcinomas, and lymphomas. We report a single case from a tertiary care institution of an adolescent male with an unusual presentation of a benign nasopharyngeal mass and provide a comprehensive review of pediatric nasopharyngeal masses. Whenever possible, radiographic imaging should be obtained, in addition to biopsy, to assist in the diagnosis of pediatric nasopharyngeal masses.

Increased expression of annexin I is associated with drug-resistance in nasopharyngeal carcinoma and other solid tumors

Adjuvant chemotherapy alongside radiotherapy is one of the effective therapies in nasopharyngeal carcinoma (NPC) treatment. However, the appearance of drug resistance is a major obstacle for anti-cancer chemotherapy and often causes failure of the chemotherapy. In this study, a drug-resistant gene annexin I (ANX-I) was identified by comparing differentially expressed proteins between a cisplatin (CDDP)-resistant NPC cell line CNE2-CDDP and parental CNE2 cells using 2-DE. When ANX-I was transfected into CNE2 cells, the CDDP resistance of CNE2 cells was dramatically increased. The drug-resistant ability of ANX-I was demonstrated by both in vitro and in vivo assays. The association of ANX-I expression with clinical features was also investigated. Increased expression of ANX-I was significantly associated with disease relapse in NPC (p<0.05). In breast and gastric cancer, increased expression of ANX-I was significantly associated with drug resistance (p<0.001) and poor prognosis (p<0.001), respectively. Taken together, our findings suggest that ANX-I plays an important role in drug resistance.

Tumor microenvironment macrophage inhibitory factor directs the accumulation of interleukin-17-producing tumor-infiltrating lymphocytes and predicts favorable survival in nasopharyngeal carcinoma patients

The accumulation of an intratumoral CD4(+) interleukin-17-producing subset (Th17) of tumor-infiltrating lymphocytes (TILs) is a general characteristic in many cancers. The relationship between the percentage of Th17 cells and clinical prognosis differs among cancers. The mechanism responsible for the increasing percentage of such cells in NPC is still unknown, as is their biological function. Here, our data showed an increase of Th17 cells in tumor tissues relative to their numbers in normal nasopharynx tissues or in the matched peripheral blood of NPC patients. Th17 cells in tumor tissue produced more IFNγ than did those in the peripheral blood of matched NPC patients and healthy controls. We observed high levels of CD154, G-CSF, CXCL1, IL-6, IL-8, and macrophage inhibitory factor (MIF) out of 36 cytokines examined in tumor tissue cultures. MIF promoted the generation and recruitment of Th17 cells mediated by NPC tumor cells in vitro; this promoting effect was mainly dependent on the mammalian target of rapamycin pathway and was mediated by the MIF-CXCR4 axis. Finally, the expression level of MIF in tumor cells and in TILs was positively correlated in NPC tumor tissues, and the frequency of MIF-positive TILs was positively correlated with NPC patient clinical outcomes. Taken together, our findings illustrate that tumor-derived MIF can affect patient prognosis, which might be related to the increase of Th17 cells in the NPC tumor microenvironment.

Biomarkers for use in monitoring responses of nasopharyngeal carcinoma cells to ionizing radiation

Nasopharyngeal carcinoma (NPC) is a common head and neck cancer. The incidence rate is higher in southern China and Southeast Asia in comparison with the Western countries. Radiotherapy is the standard treatment of NPC as the cancer cells are sensitive to ionizing radiation. Radiation treatment has good local control to patients with early NPC. It is essential to monitor the response of the NPC cells to radiation treatment in advance in order to select suitable treatment choice for the patients. This review aims to discuss the potential use of biomarkers in monitoring the responsiveness of NPC cells to radiation treatment.

High expression of p300 is linked to aggressive features and poor prognosis of nasopharyngeal carcinoma

BACKGROUND

Increased expression of transcriptional coactivator p300 has been observed in a variety of human cancers. However, the expression status of p300 protein/mRNA in nasopharyngeal carcinoma (NPC) tissues and its clinicopathologic/prognostic implication are poorly understood.

METHODS

In our study, mRNA and protein expression levels of p300 was explored by reverse transcription-polymerase chain reaction (RT-PCR), Western blotting (WB) and immunohistochemistry (IHC) in nasopharyngeal mucosal and NPC tissues. The data were analyzed by receiver operating characteristic (ROC) curve analysis, spearman's rank correlation, Kaplan-Meier plots and Cox proportional hazards regression model.

RESULTS

Up-regulated expression of p300 mRNA/p300 protein was detected in NPC tissues by RT-PCR and WB, when compared to nasopharyngeal mucosal tissues. Based on ROC curve analysis, the cutoff score for p300 high expression was defined when more than 35% of the tumor cells were positively stained. High expression of p300 was observed in 127/209 (60.7%) of NPCs. In NPCs, high expression of p300 was positively associated with later T classification, later N classification, distant metastasis and later clinical stage (P < 0.05). In univariate survival analysis, overexpression of p300 was found to be an indicator of progression-free (P = 0.002) and overall survival (P = 0.001) in NPCs. More importantly, p300 expression was evaluated as an independent prognostic factor for NPC in multivariate analysis (P = 0.036).

CONCLUSIONS

Our findings support that high expression of p300 protein might be important in conferring a more aggressive behavior, and is an independent molecular marker for shortened survival time of patients with NPC.

Undifferentiated carcinoma of the oropharynx: a human papillomavirus-associated tumor with a favorable prognosis

Undifferentiated carcinoma (undifferentiated carcinoma, nasopharyngeal type, or lymphoepithelial carcinoma) is an uncommon and histologically distinct tumor in the oropharynx, which in Western countries, has been clearly shown not to harbor Epstein Barr virus (EBV). We sought to analyze these tumors for human papillomavirus (HPV) and to examine their clinical outcomes. All cases of oropharyngeal carcinoma diagnosed as 'undifferentiated' or 'lymphoepithelial' were retrieved from the department files at Barnes-Jewish Hospital. After consensus review by all three study pathologists, 16 were found to have diagnostic histological features and to lack distinguishing characteristics of other oropharyngeal cancers. Immunohistochemistry for p16 and p53 and in-situ hybridization for HPV and EBV encoded small RNA were performed. p16-positive but HPV in situ hybridization-negative cases were analyzed by polymerase chain reaction for high-risk HPV types. The results were correlated with pathological findings and clinical follow up. There were 16 patients. The average age was 59.2 years, 14 patients (88%) were smokers, and 13 (81%) had nodal metastases. In all, 14 cases (88%) were p16 positive and 15 (94%) were HPV positive by in situ hybridization and/or polymerase chain reaction. All cases were negative for EBV, and p53 was overexpressed in five (33%), four of which were HPV positive. Disease recurred in only three patients and two of these died with disease at 38 and 136 months, respectively. Three year overall, disease-free, and disease-specific survival rates were 54, 78, and 100%, respectively. In summary, in our patient population, the majority of oropharyngeal undifferentiated carcinomas harbor transcriptionally active HPV but not EBV. Almost all overexpress p16, and few have p53 overexpression. Disease-specific survival is comparable to published rates for other HPV-related oropharyngeal squamous cell carcinoma variants and is better than that of HPV-negative carcinomas.

Second malignant tumors after treatment of nasopharyngeal carcinoma: four case reports and literature review

The purpose of this study was to identify the histopathology, location, and latency interval for the development of second malignant tumors (SMT) after successful treatment for nasopharyngeal carcinoma (NPC). Of 55 patients, four developed SMT after successful treatment of NPC in a single institutional series for an incidence of 7%. An additional 31 patients with SMT after treatment for NPC were identified from the literature. At minimum, all patients were treated with radiotherapy to the primary site. The histopathology of SMT included sarcoma (69%), squamous cell carcinoma (17%), adenocarcinoma (6%), meningioma (6%), and lymphoma (3%). SMT occurred at various sites in the head and neck, but most (51%) arose in the sinonasal cavity. For the entire group, the mean latency interval between treatment for NPC and the development of SMT was 11.8 years. These findings indicate that the development of SMT in patients achieving long-term survival after treatment for NPC may be radiation induced. Long-term follow-up for these patients is important to assess for this potentially late complication.

Arsenic mediated disruption of promyelocytic leukemia protein nuclear bodies induces ganciclovir susceptibility in Epstein-Barr positive epithelial cells

Promyelocytic leukemia protein nuclear bodies (PML NBs) have been implicated in host immune response to viral infection. PML NBs are targeted for degradation during reactivation of herpes viruses, suggesting that disruption of PML NB function supports this aspect of the viral life cycle. The Epstein-Barr virus (EBV) Latent Membrane Protein 1 (LMP1) has been shown to suppress EBV reactivation. Our finding that LMP1 induces PML NB immunofluorescence intensity led to the hypothesis that LMP1 may modulate PML NBs as a means of maintaining EBV latency. Increased PML protein and morphometric changes in PML NBs were observed in EBV infected alveolar epithelial cells and nasopharyngeal carcinoma cells. Treatment with low dose arsenic trioxide disrupted PML NBs, induced expression of EBV lytic proteins, and conferred ganciclovir susceptibility. This study introduces an effective modality to induce susceptibility to ganciclovir in epithelial cells with implications for the treatment of EBV associated pathologies.

Metastatic retropharyngeal lymph nodes in nasopharyngeal carcinoma: imaging criteria

Evaluation of: Zhang GY, Liu LZ, Wei WH, Deng YM, Li YZ, Liu XW. Radiologic criteria of retropharyngeal lymph node metastasis in nasopharyngeal carcinoma treated with radiation therapy. Radiology 255(2), 605-612 (2010). Nasopharyngeal carcinoma (NPC) is the most common nasopharyngeal neoplasm and has a high propensity for developing regional neck adenopathy. NPC arises most often in the fossa of Rosenmüller, and differs significantly from other head and neck cancers with respect to its incidence, etiology, clinical behavior and treatment. NPC is commonly associated with retropharyngeal nodes. As retropharyngeal nodes are anatomically difficult to approach for biopsy/fine-needle aspiration cytology, imaging plays a critical role in their detection and staging. The paper by Zhang et al. reports data on 303 NPC patients from a large center in China and highlights specific radiologic criteria for assessing retropharyngeal nodal metastases in nasopharyngeal carcinoma.

Nasopharyngeal carcinoma in a south European population: epidemiological data and clinical aspects in Portugal

The incidence of nasopharyngeal carcinoma (NPC) varies worldwide, with higher rates in southern Asia, intermediate rates in Mediterranean basin countries as well as in Greenland and Alaska populations, and low rates in most of the western countries. The percentage of NPC types seems to vary according to the WHO classification. Portugal is also a Mediterranean basin country. The NPC patterns in Portuguese population is comparatively analyzed with a review of the related literature, concerning the overall incidence, male/female ratio, age of incidence, WHO type frequency, Epstein-Barr virus relationship and genetic susceptibility. The particular findings in the Portuguese population can be discussed in the light of genetic background and close relationships with potential exogenous oncogenic factors.

Stable expression of EBV-gp350 on the surface of NC37 cells confers natural killer (NK)-cell susceptibility or resistance, depending on the assay used to assess NK-mediated function

NC37 cells containing the Epstein-Barr virus (EBV) genome do not express the viral glycoprotein-350 (gp350) on the cell surface. Despite being a cancer cell line, NC37 cells show resistance to natural killer (NK) cell cytotoxicity by the standard chromium ((51)Cr) release assay (CRA). EBV-gp350 has been identified as a ligand for antibody dependent cell-mediated cytotoxicity (ADCC). The stable expression of gp350 on the NC37 cell surface membrane could make this cell line a suitable target for measuring ADCC antibody. The pcDNA3.1-gp350 was transfected into the stably expressing enhanced green fluorescent protein (EGFP)-NC37 cell line. The transfected cells were then selected for expression of gp350 on the cell surface using immunomagnetic bead-based sorting. The gp350-EGFP-NC37 cell line was then re-examined for resistance to NK cytotoxicity, and compared with the standard K562 and EGFP-K562 cell lines using the CRA and a flow cytometric method, respectively. Surprisingly, the gp350-EGFP-NC37 cells, like the parental NC37 cell line, showed comparable resistance to NK cell-mediated cytotoxic activity by the CRA, while demonstrating susceptibility to NK cell cytotoxicity comparable to EGFP expressing K562 cells by the flow cytometric method. The susceptibility of gp350-EGFP-NC37 cells to NK cell cytotoxic activity is dependent on the type of assay.

Molecular diagnosis of nasopharyngeal carcinoma using detection of Epstein-Barr virus latent membrane protein-1 gene in cervical metastatic lymph nodes

BACKGROUND

Cervical lymphadenopathy could be a manifestation of occult nasopharyngeal carcinoma (NPC). Epstein-Barr virus (EBV) is frequently detected in NPC, and its malignant transformation is associated through the action of the oncoprotein latent membrane protein-1 (LMP-1).

PURPOSE

The aim of this study was to investigate whether a primary nasopharyngeal origin could be localized by detection of EBV LMP-1 gene in cervical metastatic lymph nodes.

MATERIALS AND METHODS

In this prospective study, 32 paraffin-embedded tissues of various head and neck carcinomas and 20 normal tonsil specimens were examined for the presence of LMP-1 gene, using polymerase chain reaction.

RESULTS

Ten of 12 nasopharyngeal biopsies and 8 of 10 metastatic lymph nodes of the same NPC were positive for LMP-1 gene. The LMP-1 gene was detected in metastatic lymph nodes of NPC, with a sensitivity of 80%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 91%. On the contrary, the LMP-1 gene was not detected in any of the samples of other head and neck carcinomas and their metastatic nodes as well as in tonsillar specimens. There was a significant association between the presence of LMP-1 gene and tumor location in the nasopharynx (P < .0001).

CONCLUSION

The presence of LMP-1 gene in metastatic cervical lymph nodes is significantly associated with nasopharyngeal origin of the carcinoma. Meanwhile, EBV has no role in the tumorigenesis of carcinomas arising from other head and neck regions.

Nasopharyngeal carcinoma--review of the molecular mechanisms of tumorigenesis

Nasopharyngeal carcinoma (NPC) is a head and neck cancer rare throughout most of the world but common in certain geographic areas, such as southern Asia. While environmental factors and genetic susceptibility play important roles in NPC pathogenesis, the Epstein-Barr virus in particular has been implicated in the molecular abnormalities leading to NPC. There is upregulation of cellular proliferation pathways such as the Akt pathway, mitogen-activated protein kinases, and the Wnt pathway. Cell adhesion is compromised due to abnormal E-cadherin and beta-catenin function. Aberrations in cell cycle are due to dysregulation of factors such as p16, cyclin D1, and cyclin E. Anti-apoptotic mechanisms are also upregulated. There are multiple abnormalities unique to NPC that are potential targets for novel treatments.

Genetic polymorphisms of TLR3 are associated with Nasopharyngeal carcinoma risk in Cantonese population

Background

Nasopharyngeal carcinoma is endemic in Southern China, displays a strong relationship with genetic susceptibility and associates with Epstein-Barr virus infection. Toll-like receptor 3 (TLR3) plays an important role in the antivirus response. Therefore, we examined the association between TLR3 gene polymorphisms and NPC susceptibility.

Methods

We performed a case-control study of 434 NPC cases and 512 healthy controls matched on age, sex and residence. Both cases and controls are of Cantonese origin from Southern China. Genetic variants in TLR3 were determined by polymerase chain reaction (PCR)-based DNA direct sequencing and four SNPs were genotyped in all samples.

Results

Our results showed that allele C for SNP 829A/C increased NPC risk significantly ((p = 0.0068, OR = 1.49, 95%CI:1.10–2.00). When adjusted for age, gender and VCA-IgA antibody titers, the NPC risk was reduced significantly among individuals who carried the haplotype "ATCT" compared to those who carried the most common haplotype "ACCT" (p = 0.0054, OR = 0.028; 95% CI (0.002–0.341).

Conclusion

The TLR3 polymorphisms may be relevant to NPC susceptibility in the Cantonese population, although the reduction in NPC risk is modest and the biological mechanism of the observed association merits further investigation.

No evidence of Epstein-Barr virus association with Merkel cell carcinoma

BACKGROUND

Merkel cell carcinoma (MCC) is an aggressive tumor of cutaneous neuroendocrine cells with a reported 13-fold increased incidence in immunocompromised patients, raising the possibility that it is driven by an oncogenic virus. Additionally, Merkel cell hyperplasia is seen in the Epstein-Barr virus (EBV)-driven process oral hairy leukoplakia, and EBV is known to be involved in the pathogenesis of several other malignancies.

OBJECTIVE

We tested the hypothesis that EBV is involved in MCC.

METHODS

We employed EBV-encoded RNA in situ hybridization (ISH), lytic EBV ISH, latent membrane protein 1 immunohistochemistry, and BamH1Z leftward reading frame 1 immunohistochemistry to detect and localize EBV in paraffin sections of MCC from five patients as well as seven other cutaneous tumors and positive controls for EBV infection.

RESULTS

Positive controls reacted appropriately. However, there was no evidence of latent or lytic EBV in any of the MCC biopsies or other cutaneous tumors.

CONCLUSION

Our findings suggest that EBV is not associated with MCC.