Treatment approaches to nasopharyngeal carcinoma: a review. Anticancer Drugs. 2010;21:471-477. [PMID: 20124988 DOI: 10.1097/cad.0b013e328337160e]

The role and mechanism of aerobic glycolysis in nasopharyngeal carcinoma

This review delves into the pivotal role and intricate mechanisms of aerobic glycolysis in nasopharyngeal carcinoma (NPC). NPC, a malignancy originating from the nasopharyngeal epithelium, displays distinct geographical and clinical features. The article emphasizes the significance of aerobic glycolysis, a pivotal metabolic alteration in cancer cells, in NPC progression. Key enzymes such as hexokinase 2, lactate dehydrogenase A, phosphofructokinase 1, and pyruvate kinase M2 are discussed for their regulatory functions in NPC glycolysis through signaling pathways like PI3K/Akt and mTOR. Further, the article explores how oncogenic signaling pathways and transcription factors like c-Myc and HIF-1α modulate aerobic glycolysis, thereby affecting NPC's proliferation, invasion, metastasis, angiogenesis, and immune evasion. By elucidating these mechanisms, the review aims to advance research and clinical practice in NPC, informing the development of targeted therapeutic strategies that enhance treatment precision and reduce side effects. Overall, this review offers a broad understanding of the multifaceted role of aerobic glycolysis in NPC and its potential impact on therapeutic outcomes.

Biocompatibility and potential anticancer activity of gadolinium oxide (Gd2O3) nanoparticles against nasal squamous cell carcinoma

Chemotherapy as a cornerstone of cancer treatment is slowly being edged aside owing to its severe side effects and systemic toxicity. In this case, nanomedicine has emerged as an effective tool to address these drawbacks. Herein, a biocompatible carrier based on bovine serum albumin (BSA) coated gadolinium oxide nanoparticles (Gd2O3@BSA) was fabricated for curcumin (CUR) delivery and its physicochemical features along with its potential anticancer activity against nasal squamous cell carcinoma were also investigated. It was found that the fabricated Gd2O3@BSA containing CUR (Gd2O3@BSA-CUR) had spherical morphology with hydrodynamic size of nearly 26 nm, zeta-potential of -36 mV and high drug (CUR) loading capacity. Drug release profile disclosed that the release of CUR from the prepared Gd2O3@BSA-CUR nanoparticles occurred in a sustained- and pH-dependent manner. Also, in vitro cytotoxicity analysis revealed that the fabricated Gd2O3@BSA nanoparticles possessed excellent biosafety toward HFF2 normal cells, while Gd2O3@BSA-CUR appeared to display the greatest anticancer potential against RPMI 2650 and CNE-1 cancer cell lines. The results also show that the Gd2O3@BSA nanoparticles were compatible with the blood cells with minor hemolytic effect (< 3%). The manufactured NPs were found to be completely safe for biological applications in an in vivo subacute toxicity study. Taken together, these finding substantiate the potential anticancer activity of Gd2O3@BSA-CUR nanoparticles against nasal squamous cell carcinoma, but the results obtained demand further studies to assess their full potential.

Multimodal treatment according to the NPC-GPOH trials in adult patients with nasopharyngeal cancer-Analysis based on a single-center experience

BACKGROUND AND AIM

The German NPC-GPOH trials introduced treatment including neoadjuvant chemotherapy, radiochemotherapy (RCT) and antiviral treatment in patients aged 25 years or younger with nasopharyngeal cancer (NPC). We conducted a retrospective study on outcomes of patients at the age of ≥26 years treated accordingly at our institution.

METHODS

Consecutive patients who received primary RCT for NPC were included. The Kaplan-Meier method was used to calculate survival probabilities, and the Cox regression analysis was used to test for an influence of the variables on outcomes. Acute and late toxicity were evaluated via CTCAE criteria and LENT/SOMA criteria, respectively.

RESULTS

In total, 30 patients were included. Diagnosis was made from 09/1994 to 11/2016. The median 5 year overall survival (OS), disease-free survival (DFS), cancer-specific survival (CSS) and locoregional recurrence-free survival (LRC) were 75%, 56%, 83%, and 85%, respectively. We found a negative impact on outcomes (p < .05) in case of older age (OS), history of smoking (OS), and T4 stage/ UICC stage IV (DFS). WHO histologic type significantly influenced outcomes, with best outcomes for type III and worst outcomes for type I. The rates of acute and late toxicities were acceptable.

CONCLUSION

We found excellent outcomes and good feasibility of the NPC-GPOH trials regimen in adult patients. Additionally, we identified patients with outcomes which need to be improved (smokers, histologic type I tumors) and with particularly excellent outcomes (histologic type III tumors). This stimulates further studies on treatment intensification or de-escalation aiming at reduced side effects with optimal tumor control in NPC.

Combining Nimotuzumab With Chemotherapy for Patients With Locally Advanced and Intermediate-Stage Nasopharyngeal Cancer: A Retrospective Comparison Study Using Five-Year, Real-World Survival Data

BACKGROUND

Nasopharyngeal carcinoma (NPC) is the most prevalent geographically-specific head and neck cancer. Its incidence was high in the Asian population, especially in certain parts such as Southern China and South East Asia. Most patients with NPC are presented with intermediate-stage or locally advanced disease requiring chemoradiation as the primary treatment of choice. Epidermal Growth Factor Receptor (EGFR) was found overexpressed in most patients with NPC associated with poor prognosis making its inhibitor one of the most plausible treatment options in addition to chemoradiation. In EGFR-positive NPC patients, nimotuzumab, a humanized anti-EGFR monoclonal antibody will bind the extracellular domain of EGFR leading to tumor growth suppressions. This study's objective was to assess the real-world clinical efficacy of nimotuzumab for patients with intermediate-stage and locally advanced NPC when in combination with concurrent chemoradiation.

METHODS

This retrospective real-world study examined a sample of intermediate-stage and locally advanced NPC patients who were treated with or without adding nimotuzumab to concurrent chemoradiation at Dr. Cipto Mangunkusumo General Hospital in Indonesia from January 2009 to December 2017. The outcomes were patients' real-world five-year overall survival (rwOS) and progression-free survival (rwPFS) compared using Kaplan-Meier analysis and Cox proportional hazard models adjusting for age, gender, comorbidities, clinical staging, staging based on Tumor status (T), staging based on Nodes status (N), and types of radiotherapy.  Results: A total of 407 patients were included in the analysis, 61 patients receiving concurrent nimotuzumab and chemoradiation and 346 patients receiving chemoradiation alone. Patients receiving concurrent nimotuzumab and chemoradiation tended to have less aggressive NPC than patients receiving chemoradiation alone. Multivariate-adjusted Cox models revealed that combining nimotuzumab with chemoradiation was associated with a statistically significant longer rwOS gain (hazard ratio (HR)=0.46 (95% CI: 0.26-0.82, p=0.008)) and a trend of longer rwPFS (hazard ratio (HR)=0.67 (95% CI: 0.41-1.09, p=0.109)) in comparison to chemoradiation alone.  Conclusion: In this retrospective real-world study, concurrent nimotuzumab and chemoradiation usage was associated with a significant overall survival benefit than chemoradiation alone for intermediate-stage and locally advanced NPC patients. Hence, adding nimotuzumab to patients' chemoradiation should be considered in patients with intermediate-stage and locally advanced NPC.

Targeted therapy for head and neck squamous cell carcinoma microenvironment

Head and neck squamous cell carcinoma (HNSCC) originates from the squamous epithelium of the oral cavity, oropharynx, larynx, and hypopharynx. HNSCC in the oral cavity and larynx is strongly associated with tobacco smoking and alcohol consumption, while oropharyngeal cancer is increasingly attributed to infection by human papillomavirus (HPV), particularly HPV-16. The tumor microenvironment (TME) is a complex network of cancer cells, immune cells, stromal cells, surrounding blood vessels, and signaling molecules, and plays a critical role in tumor cell survival, invasion, and recurrence. Therefore, it is critical to elucidate the molecular basis of the interaction between tumor cells and the TME in order to develop innovative anti-cancer therapeutic strategies.

Impact of Epstein Barr Virus Infection on Treatment Opportunities in Patients with Nasopharyngeal Cancer

Chemical, physical, and infectious agents may induce carcinogenesis, and in the latter case, viruses are involved in most cases. The occurrence of virus-induced carcinogenesis is a complex process caused by an interaction across multiple genes, mainly depending by the type of the virus. Molecular mechanisms at the basis of viral carcinogenesis, mainly suggest the involvement of a dysregulation of the cell cycle. Among the virus-inducing carcinogenesis, Epstein Barr Virus (EBV) plays a major role in the development of both hematological and oncological malignancies and importantly, several lines of evidence demonstrated that nasopharyngeal carcinoma (NPC) is consistently associated with EBV infection. Cancerogenesis in NPC may be induced by the activation of different EBV "oncoproteins" which are produced during the so called "latency phase" of EBV in the host cells. Moreover, EBV presence in NPC does affect the tumor microenvironment (TME) leading to a strongly immunosuppressed status. Translational implications of the above-mentioned statements are that EBV-infected NPC cells can express proteins potentially recognized by immune cells in order to elicit a host immune response (tumor associated antigens). Three immunotherapeutic approaches have been implemented for the treatment of NPC including active, adoptive immunotherapy, and modulation of immune regulatory molecules by use of the so-called checkpoint inhibitors. In this review, we will highlight the role of EBV infection in NPC development and analyze its possible implications on therapy strategies.

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.

The Nasopharyngeal Carcinoma and Its Effect on the Infectious Eye Disease: A Nationwide Cohort Study

The purpose of this study is to investigate the potential correlation between nasopharyngeal carcinoma (NPC) and both infectious keratitis and orbital cellulitis. The retrospective cohort study used the National Health Insurance Research Database (NHIRD) as a data source. A total number of 4184 patients with NPC diagnosis were selected and matched to 16,736 non-NPC patients via the propensity-score matching (PSM). The main outcomes are the development of infectious keratitis and orbital cellulitis according to diagnostic codes and related medications. The Cox proportional hazard regression was adopted to estimate the adjusted hazard ratio (aHR) and 95% confidence interval (CI) of outcomes between the two groups. A total of 35 and 19 episodes of orbital cellulitis occurred in the NPC and non-NPC groups and the aHR was significantly higher in the NPC group (aHR: 1.34, 95% CI: 1.23−1.46, p = 0.0024). There were 2185 and 659 events of infectious keratitis in the NPC and non-NPC groups, and the NPC group revealed a significantly higher aHR than non-NPC group (aHR: 1.34, 95% CI: 1.23−1.46, p < 0.0001). Besides, the cumulative probability of infectious keratitis was significantly higher in the NPC group than the non-NPC group (p < 0.0001). The other risk factors of infectious keratitis include age from 20 to 30 years old, allergic respiratory diseases, allergic dermatological diseases, and external eye diseases (all p < 0.0001). In subgroup analyses, both the incidences of infectious keratitis (aHR: 1.33, 95% CI: 1.21−1.47) and orbital cellulitis (aHR: 2.36, 95% CI: 1.27−4.39) were significantly higher than the non-NPC group. The incidence of infectious keratitis was significantly higher in NPC patients without radiotherapy (aHR: 1.40, 95% CI: 1.26−1.55) compared to non-NPC population, while the rate of orbital cellulitis was similar between the NPC patients without radiotherapy (aHR: 0.76, 95% CI: 0.27−2.14) and non-NPC population. In conclusion, the existence of NPC associates with higher incidence of infectious keratitis which increases with NPC period, and the radiotherapy may be account for the higher rate of orbital cellulitis in NPC population.

Exosomal miR-106a-5p accelerates the progression of nasopharyngeal carcinoma through FBXW7-mediated TRIM24 degradation

Nasopharyngeal carcinoma (NPC) is prevalent in East Asia and causes increased health burden. Elucidating the regulatory mechanism of NPC progression is important for understanding the pathogenesis of NPC and developing novel therapeutic strategies. Nasopharyngeal carcinoma and normal tissues were collected. Nasopharyngeal carcinoma cell proliferation, migration, and invasion were evaluated using CCK-8, colony formation, wound healing, and transwell assays, respectively. A xenograft mouse model of NPC was established to analyze NPC cell growth and metastasis in vivo. The expression of miR-106a-5p, FBXW7, TRIM24, and SRGN was determined with RT-qPCR and Western blot. MiR-106a-5p, TRIM24, and SRGN were upregulated, and FBXW7 was downregulated in NPC tissues and cells. Exosomal miR-106a-5p could enter NPC cells, and its overexpression promoted the proliferation, migration, invasion, and metastasis of NPC cells, which were suppressed by knockdown of exosomal miR-106a-5p. MiR-106a-5p targeted FBXW7 to regulate FBXW7-mediated degradation of TRIM24. Furthermore, TRIM24 regulated SRGN expression by binding to its promoter in NPC cells. Suppression of exosomal miR-106a-5p attenuated NPC growth and metastasis through the FBXW7-TRIM24-SRGN axis in vivo. Exosomal miR-106a-5p accelerated the progression of NPC through the FBXW7-TRIM24-SRGN axis. Our study elucidates novel regulatory mechanisms of NPC progression and provides potential exosome-based therapeutic strategies for NPC.

Knockdown of Annexin A2 Enhances Radiosensitivity by Increasing G2/M-Phase Arrest, Apoptosis and Activating the p38 MAPK-HSP27 Pathway in Nasopharyngeal Carcinoma

Annexin A2 (ANXA2) has been found to be involved in cancer proliferation, metastasis and prognosis; however, its exact role in nasopharyngeal carcinoma (NPC) radioresistance remains unknown. We found that ANXA2 expression was correlated with prognosis in NPC patients, and longer overall survival in NPC patients with low ANXA2 expression than those with high ANXA2 expression. ANXA2 knockdown increased the radiosensitivity in radioresistant NPC cells, and ANXA2 overexpression decreased the radiosensitivity in NPC cells. Knocking-down ANXA2 expression increased the irradiation-induced apoptosis of radioresistant NPC cells, and ANXA2 overexpression decreased the irradiation-induced apoptosis of NPC cells. ANXA2 knockdown induced G2/M phase arrest in NPC cells post-irradiation, and ANXA2 overexpression abrogated G2/M phase arrest in NPC cells post-irradiation. ANXA2 overexpression resulted in inhibition of the p38 MAPK-HSP27 pathway, while ANXA2 knockdown resulted in activation of the p38 MAPK-HSP27 pathway. In addition, ANXA2 knockdown increased the radiosensitivity of the xenografted tumors in nude mice. Our data demonstrate that knockdown of Annexin A2 enhanced radiosensitivity in NPC by increasing G2/M-phase arrest, apoptosis and activating the p38 MAPK-HSP27 pathway. ANXA2 may be a promising target used to overcome radioresistance in NPC.

Kiss1 Inhibits the Proliferation of Nasopharyngeal Carcinoma Cells Via Activation of the LKB1/AMPK Pathway

Nasopharyngeal carcinoma (NPC) is a cancer that occurs in the nasopharynx. Infinite proliferation and distant metastasis are the main characteristics of NPC cells, and the main reason for the current failure of malignant tumor treatment. In this study, by integrating the immunohistochemical, cell transfection, western blot and real-time reverse transcriptase polymerase chain reaction (RT-PCR) analysis, we observed that the expression of KISS1 and its receptor gene (KISS1R) negatively related with the proliferation of NPC cells. Overexpression of the KISS1 genes in cells reduced cell proliferation, slow down the cell cycle, and increased apoptosis. Additionally, overexpression of these genes significantly increased Liver Kinase B1 (LKB1), phosphorylation of LKB1 and AMPK, indicated by Western blotting. Together, all of these results suggested for the first time that KISS1 and KISS1R suppress the proliferation of NPC cells by activating the LKB1/AMPK pathway, thus revealing a viable indicator for diagnosis of NPC in clinical practice.

Estimating the global burden of Epstein-Barr virus-related cancers

BACKGROUND

More than 90% of the adult population globally is chronically infected by the Epstein-Barr virus (EBV). It is well established that EBV is associated with a number of malignancies, and advances in knowledge of EBV-related malignancies are being made every year. Several studies have analysed the global epidemiology and geographic distribution of EBV-related cancers. However, most have only described a single cancer type or subtype in isolation or limited their study to the three or four most common EBV-related cancers. This review will present an overview on the spectrum of cancers linked to EBV based on observations of associations and proportions in the published literature while also using these observations to estimate the incidence and mortality burden of some of these cancers.

METHOD

We have reviewed the literature on defining features, distribution and outcomes across six cancers with a relatively large EBV-related case burden: Nasopharyngeal carcinoma (NPC), Gastric carcinoma (GC), Hodgkin lymphoma (HL), Burkitt lymphoma (BL), Diffuse large B-cell lymphoma (DLBCL) and Extranodal NK/T-cell lymphoma, Nasal type (ENKTL-NT). We retrieved published region-specific EBV-related case proportions for NPC, GC, HL and BL and performed meta-analyses on pooled region-specific studies of EBV-related case proportions for DLBCL and ENKTL-NT. We match these pooled proportions with their respective regional incidence and mortality numbers retrieved from a publicly available cancer database. Additionally, we also reviewed the literature on several other less common EBV-related cancers to summarize their key characteristics herein.

CONCLUSION

We estimated that EBV-related cases from these six cancers accounted for 239,700-357,900 new cases and 137,900-208,700 deaths in 2020. This review highlights the significant global impact of EBV-related cancers and extends the spectrum of disease that could benefit from an EBV-specific therapeutic.

GADD45B induced the enhancing of cell viability and proliferation in radiotherapy and increased the radioresistance of HONE1 cells

This study aimed to investigate the key role and mechanism of GADD45B in the radiation resistance of nasopharyngeal carcinoma (NPC) cell lines. Radiotherapy-resistant HONE1 (HONE1-R) cells with stable genetic radioresistance were cultured under continuous radiation stimulation. CCK-8 and clone formation assays were used to verify the radioresistance of the cell line. Transcriptome sequencing was used to identify the most important differential signaling pathway in the cell line. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot analysis were used to verify the sequencing results. GADD45B-siRNA was used to knock down the key gene so as to verify the downstream gene expression and analyze its mechanism. The transcriptome analysis showed that 702 genes were upregulated and 772 genes were downregulated in the HONE1-R cell lines. The core differential signaling pathway was mitogen-activated protein kinase (MAPK) signaling pathway, and the core differential gene was GADD45B. After GADD45B was knocked down, the cell viability and proliferation ability of HONE1-R cell lines significantly decreased under radiation, and the expression of cyclin B1 and p-CDK1 decreased significantly. MAPK is the core signaling pathway in radioresistance of NPC. GADD45B plays an important role by affecting cell viability and proliferation in NPC radioresistance. GADD45B is a potential target of radioresistance in NPC.

Ophiopogonin B induces reactive oxygen species‑dependent apoptosis through the Hippo pathway in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a common malignant tumor in South China and is characterized by a high death rate. Ophiopogonin B (OP‑B) is a bioactive component of Radix Ophiopogon japonicus, which is frequently used in traditional Chinese medicine to treat cancer. The present study aimed to examine the anti‑cancer properties of OP‑B on NPC cells. Cell viability and cell proliferation were measured using MTT and EdU assays. Flow cytometry was used to measure cell apoptosis, reactive oxygen species and mitochondrial membrane potential. Western blotting was used to investigate the expression of apoptosis and Hippo signaling pathway proteins. OP‑B inhibited the proliferation of NPC cells by inducing apoptosis and disturbing the mitochondrial integrity. OP‑B enhanced ROS accumulation. In addition, OP‑B promoted the expression of mammalian STE20‑like kinase 1, large tumor suppressor 1 and phosphorylated yes‑associated protein (YAP) and suppressed the expression of YAP and transcriptional enhanced associate domain in NPC cells. OP‑B increased the expression of forkhead box transcription factor O1 in the nuclear fraction. In conclusion, OP‑B has therapeutic potential and feasibility in the development of novel YAP inhibitors for NPC.

ADORA1 promotes nasopharyngeal carcinoma cell progression through regulation of PI3K/AKT/GSK-3β/β-catenin signaling

AIMS

For most human cancers, the expression pattern and biological function of ADORA1 (Adenosine A1 Receptor) are largely unknown. This study has been designed to explore the clinical significance and the mechanism of ADORA1 in nasopharyngeal carcinoma (NPC) cells.

MATERIALS AND METHODS

The level of ADORA1 in NPC and its adjacent tissues was analyzed by IHC, real-time PCR and western blotting. MTT and colony formation assays were used to determine the cell viability post ADORA1 overexpression or knockdown. Wound-healing assay and Transwell assay were used to analyze the effect of ADORA1 on migration and invasion. Moreover, the effect of ADORA1 on tumor growth was also studied in vivo by using xenograft mouse model. The regulation of ADORA1 on PI3K/AKT/GSK-3β/β-catenin pathway was determined by western blotting and TOP-Flash luciferase assay.

KEY FINDINGS

Primary NPC exhibits overexpression of ADORA1, which is related to the overexpression of its mRNA. Ectopic expression of ADORA1 promotes the proliferation, invasion and migration in NPC cells. The apoptosis, however, is suppressed. ADORA1 silencing was found to exert opposite effects in in vitro studies and produced a significant inhibitory effect on murine xenograft tumor growth in vivo experiments. Besides, ADORA1 also triggers the PI3K/AKT/GSK-3β/β-catenin intracellular oncogenic pathway for signal transduction. Inhibition of this pathway by PI3K inhibitor LY294002 obstructed the impact of ADORA1 on tumor development in cells with ADORA1-overexpression.

SIGNIFICANCE

ADORA1 has been identified as an important oncoprotein, promoting tumor cell proliferation via PI3K/AKT/GSK-3β/β-catenin signaling pathway in NPC.

The Prognosis Value of PSPC1 Expression in Nasopharyngeal Cancer

Background

Paraspeckle component 1 (PSPC1) is overexpressed in various cancer and correlated with poor survival in the patients. However, little is known about its expression and role in the progression of nasopharyngeal carcinomas (NPC). The purpose of this study is to examine PSPC1 expression in NPC and explore its role in clinical prognosis of radiation therapy.

Methods

The association of PSPC1 expression with clinicopathological features of 109 NPC patients was examined using partial correlation analysis. Cancer tissues were obtained prior to clinical treatment. All cases were diagnosed and pathologically confirmed to be poorly differentiated or undifferentiated NPC without distant metastasis. The patients were then treated with radiation and followed-up. Survival analysis was performed.

Results

Partial correlation analysis revealed that the PSPC1 expression in NPC was correlated with N classification, recurrence, prognosis and radiosensitivity in NPC patients, but not with the gender, age, pathohistological pattern, clinical stage, and T classification. The overexpression of PSPC1 was detected in 64 samples (58.72%). Kaplan–Meier survival analysis revealed that the overall survival (OS) was longer in NPC patients with PSPC1 low expression than that in those with PSPC1 high expression. Moreover, patients with the overexpression of PSPC1 had a low progression-free survival and distant metastasis-free survival rate, compared to those who had a low expression of PSPC1. Although not statistically significant, patients with high expression of PSPC1 had a lower locoregional recurrence-free survival rate than those with low expression, and the curves between the two groups was well separated.

Conclusion

PSPC1 overexpression was associated with poor prognosis for NPC, which might be a novel useful biomarker to predict the response of NPC to radiation therapy and its clinical outcome.

Global, regional, and national burden of nasopharyngeal carcinoma from 1990 to 2017-Results from the Global Burden of Disease Study 2017

BACKGROUND

The aim of this study is to estimate the incidence, mortality, and disability-adjusted life years (DALYs) of nasopharyngeal carcinoma from 1990 to 2017.

METHODS

We collected detailed information on nasopharyngeal carcinoma from 1990 to 2017 based on data from Global Burden of Disease (GBD) study 2017. The global incidence, mortality, and DALYs attributable to nasopharyngeal carcinoma was reported, as well as the age-standardized rates (ASRs).

RESULTS

The ASR of nasopharyngeal carcinoma incidence decreased from 1.88 (95% UI: 1.76-2.00) in 1990 to 1.35 (95% UI: 1.28-1.42) in 2017. The ASR of mortality decreased from 1.19 (95% UI: 1.13-1.25) in 1990 to 0.86 (95% UI: 0.82-0.89) in 2017, while ASR-DALYs decreased from 38.2 (95% UI: 35.9-40.2) in 1990 to 25.4 (95% UI: 24.4-26.5) in 2017.

CONCLUSIONS

The ASR of incidence, mortality, and DALYs of nasopharyngeal carcinoma have decreased slightly worldwide. East Asia carried the heaviest burden of nasopharyngeal carcinoma. The majority of nasopharyngeal carcinoma burden was observed in men, especially among male aged 55 to 69 years.

Advances in targeted therapy mainly based on signal pathways for nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant epithelial carcinoma of the head and neck region which mainly distributes in southern China and Southeast Asia and has a crucial association with the Epstein-Barr virus. Based on epidemiological data, both incidence and mortality of NPC have significantly declined in recent decades grounded on the improvement of living standard and medical level in an endemic region, in particular, with the clinical use of individualized chemotherapy and intensity-modulated radiotherapy (IMRT) which profoundly contributes to the cure rate of NPC patients. To tackle the challenges including local recurrence and distant metastasis in the current NPC treatment, we discussed the implication of using targeted therapy against critical molecules in various signal pathways, and how they synergize with chemoradiotherapy in the NPC treatment. Combination treatment including targeted therapy and IMRT or concurrent chemoradiotherapy is presumably to be future options, which may reduce radiation or chemotherapy toxicities and open new avenues for the improvement of the expected functional outcome for patients with advanced NPC.

Prognostic role of pre-treatment serum albumin in patients with nasopharyngeal carcinoma: A meta-analysis and systematic review

BACKGROUND

Pre-treatment serum albumin (ALB) is a novel index that was identified in recent years and is considered to be closely related to the prognosis of nasopharyngeal carcinoma (NPC). However, the association between ALB and NPC remains controversial.

OBJECTIVE OF REVIEW

To assess the prognostic significance of pre-treatment serum ALB in patients with NPC.

TYPE OF REVIEW

A systematic review and meta-analysis.

SEARCH STRATEGY

We searched PubMed, the Cochrane Library and the Web of Science for studies published up to August 2018. The keywords used were related to albumin, nasopharyngeal carcinoma and prognosis.

EVALUATION METHOD

We extracted the following data from all included studies: author, publication year, country, cancer centre, time points of randomisation, sample size, mean or median age, gender, TNM stage of NPC, cut-off value of pre-treatment serum albumin, number of high-grade cases and duration of follow-up. Then, we generated the pooled hazard ratios (HR) for overall survival (OS) and distant metastasis-free survival (DMFS) to perform this meta-analysis.

RESULTS

Ten studies comprising 7339 cases were included. Lower pre-treatment serum ALB levels were significantly associated with worse OS (HR = 1.32, 95% CI 1.17-1.48) and DMFS (HR = 1.40, 95% CI 1.08-1.80). In general, our findings were further verified in the subgroup analyses based on three features, including cancer stage, cut-off value and analysis type.

CONCLUSION

A decreased level of pre-treatment serum albumin implies a poor prognosis and can be detected to define the risk stratification of NPC patients.

CRISPR/Cas9-mediated double knockout of SRPK1 and SRPK2 in a nasopharyngeal carcinoma cell line

BACKGROUND

Serine-arginine protein kinase (SRPK) is a regulator of alternative splicing events via phosphorylation of splicing factor proteins. Oncogenic roles of SRPK1 and SRPK2 have been reported in various types of cancer. To date, only SRPK1/2 specific inhibitors and small interfering RNA (siRNA) have been used for halting their function momentarily; however, there is no attempt to generate SRPK1/2 stable knockout cancer cells as a tool to investigate their roles in tumorigenesis.

AIM

Our objective is therefore to establish a nasopharyngeal carcinoma (NPC) cell line with stable SRPK1 or SRPK2 knockout and SRPK1/2 double knockout as a model to investigate their potential roles in NPC.

METHODS AND RESULTS

CNE1 was selected as a representative of NPC cell lines to create single and double knockout of SRPK1/2 proteins. SRPK1/2 KO plasmid with cas9, green fluorescent protein (GFP), and gRNA expression was cotransfected with SRPK1/2 homology-directed repair (HDR) plasmid containing puromycin resistance, red fluorescent protein (RFP), and 5' and 3' arm sequence for homologous recombination to CNE1 cells. The transfected CNE1 cells with GFP and RFP expression were sorted through fluorescence-activated cell sorting for further treatment with puromycin containing medium. This step generated stable single knockout of SRPK1 and SRPK2. The SRPK2 knockout NPC cells were used as a precursor for double knockout generation via transfection with Cre plasmid for excision of inserted material to generate puromycin-sensitive SRPK2 knockout clone. The puromycin-sensitive SRPK2 knockout cells were transfected with SRPK1 KO/HDR plasmid and treated with puromycin-containing medium. The puromycin-resistant cells of SRPK1/2 stable double knockout were expanded, and the corresponding protein expression was confirmed by western immunoblotting analysis.

CONCLUSION

Single and double knockout of SRPK1/2 were established using clustered regularly interspaced short palindromic repeats (CRISPR)/ CRISPR-associated 9 (Cas9) system in an NPC cell line as a model for investigation of their splicing mechanism in NPC.

Crucifera sulforaphane (SFN) inhibits the growth of nasopharyngeal carcinoma through DNA methyltransferase 1 (DNMT1)/Wnt inhibitory factor 1 (WIF1) axis

BACKGROUND

Sulforaphane (SFN), a natural compound present in cruciferous vegetable, has been shown to possess anti-cancer activities. Cancer stem cell (CSC) in bulk tumor is generally considered as treatment resistant cell and involved in cancer recurrence. The effects of SFN on nasopharyngeal carcinoma (NPC) CSCs have not yet been explored.

PURPOSE

The present study aims to examine the anti-tumor activities of SFN on NPC cells with CSC-like properties and the underlying mechanisms.

METHODS

NPC cells growing in monolayer culture, CSCs-enriched NPC tumor spheres, and also the NPC nude mice xenograft were used to study the anti-tumor activities of SFN on NPC. The population of cells expressing CSC-associated markers was evaluated using flow cytometry and aldehyde dehydrogenase (ALDH) activity assay. The effect of DNA methyltransferase 1 (DNMT1) on the growth of NPC cells was analyzed by using small interfering RNA (siRNA)-mediated silencing method.

RESULTS

SFN was found to inhibit the formation of CSC-enriched NPC tumor spheres and reduce the population of cells with CSC-associated properties (SRY (Sex determining Region Y)-box 2 (SOX2) and ALDH). In the functional study, SFN was found to restore the expression of Wnt inhibitory factor 1 (WIF1) and the effect was accompanied with the downregulation of DNMT1. The functional activities of WIF1 and DNMT1 were confirmed using exogenously added recombinant WIF1 and siRNA knockdown of DNMT1. Moreover, SFN was found to inhibit the in vivo growth of C666-1 cells and enhance the anti-tumor effects of cisplatin.

CONCLUSION

Taken together, we demonstrated that SFN could suppress the growth of NPC cells via the DNMT1/WIF1 axis.

Blood Cadmium Level Is Associated with Short Progression-Free Survival in Nasopharyngeal Carcinoma

The prognosis of nasopharyngeal carcinoma (NPC) is poor with disease progression. Cadmium exposure is a risk factor for NPC. We aimed to investigate the effect of cadmium exposure, by measuring cadmium level, and clinicopathologic factors on NPC disease progression and prognosis. A total of 134 NPC cases were analyzed and venous blood samples were collected. Blood cadmium level was analyzed by graphite furnace atomic absorption spectrophotometry. Clinical data were collected at baseline for patients and tumor characteristics from medical records. Progression-free survival (PFS) was analyzed during follow-up. The effect of cadmium exposure and clinical factors on PFS was analyzed by the Kaplan-Meier method and Cox regression models. Blood cadmium level was associated with history of disease and smoking history and pack-years. On Kaplan-Meier analysis, a high blood cadmium level, male sex, smoking history and increasing pack-years, as well as advanced clinical stage were all associated with short PFS. On multivariate analysis, blood cadmium level was an independent risk factor and predictor of NPC prognosis and disease progression. Cadmium exposure and related clinical factors can affect the prognosis of NPC, which merits further study to clarify.

MDM2 inhibitor RG7388 potently inhibits tumors by activating p53 pathway in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a high-risk head and neck cancer with poor clinical outcomes and insufficient treatments. The mouse double minute 2 homolog (MDM2) is the main molecular target in the clinical treatment of cancer. Indeed, MDM2 negatively regulates p53 through ubiquitin-dependent degradation. Thus, inhibition of MDM2-p53 interaction is a potential strategy for treating NPC. The latest generation MDM2 inhibitor, RG7388, shows increased potency and improved bioavailability compared to previous treatments. In this study, we investigated the efficacy and specificity of this inhibitor in NPC cell lines, and tumor-bearing mice were used to examine the therapeutic efficacy and effects of RG7388 treatment. The results showed that RG7388 potently decreased cell proliferation and activated p53-dependent pathway, resulting in cell cycle arrest and apoptosis. RG7388 significantly inhibited tumors in tumor-bearing mice. Activation of the p53 pathway-inhibited cell proliferation, as observed by detecting Ki67-positive cells. Additionally, the activity of apoptotic caspase family proteins was induced in the cleaved caspase-3-positive cells in vivo. Our results demonstrate that the MDM2 small-molecule inhibitor RG7388 is effective for NPC tumors, supporting further clinical investigation as a potential therapy for NPC.

Use of intensity-modulated radiation therapy for nasopharyngeal cancer in Japan: analysis using a national database

Background

Intensity-modulated radiation therapy (IMRT) yields better outcomes and fewer toxicities for radiation therapy (RT) of head and neck cancers (HNCs), including nasopharyngeal cancer (NPC). IMRT is the standard RT treatment and has been widely adopted in Western countries to treat HNCs. However, its uptake in clinical practice among NPC patients has never been studied.

Methods

We investigated the use of IMRT for NPC using data from a nationwide cancer registry to describe the use of IMRT among NPC patients in Japan. We analyzed the data of patients with HNC, including NPC, who underwent IMRT between 2012 and 2014, as recorded in the hospital-based cancer registries linked with insurance claims. We calculated the proportion of patients with NPC who underwent IMRT at each hospital. To evaluate the use of IMRT for NPC, the IMRT use for NPC was compared with the proportion of patients with prostate cancer who underwent IMRT.

Results

Among 508 patients with NPC who underwent RT at one of 87 hospitals, 348 (69%) underwent IMRT. This proportion gradually increased between 2012 and 2014 (62%, 64% and 77%). Meanwhile, 4790 patients with prostate cancer (90%) underwent IMRT. Although some hospitals where IMRT was performed treated many patients with NPC, the proportion of patients with NPC who were treated with IMRT was low.

Conclusions

IMRT has not been widely adopted in Japan for treating NPC. Barriers for adopting its use should be identified to close the gap between the standard and actual medical practice in Japan.

Management of recurrent nasopharyngeal carcinoma: current perspectives

Nasopharyngeal carcinoma is a rare disease in Western countries. Nevertheless, its incidence in China, Singapore, and other Eastern countries reaches 20 cases per 100,000 people. Being an extremely chemo- and radiosensitive disease, upfront treatment often consists in the association of intensity-modulated radiation therapy and concurrent cisplatin. Unfortunately, about 20% of the patients suffer from a radioresistant disease which recurs after upfront therapy. For these patients, mainly available therapeutic options consist in systemic therapy, in particular poly-chemotherapy. In those showing a single locoregional recurrence, chemotherapy is not considered to be the preferred approach and other different strategies may be employed. Re-irradiation and surgery are strategies that are always used more often, albeit related to high risk of morbidity. Immunotherapy and targeted therapy, such as heavy ions-based re-irradiations, are experimental but very intriguing options.

Trans-vaccenic acid inhibits proliferation and induces apoptosis of human nasopharyngeal carcinoma cells via a mitochondrial-mediated apoptosis pathway

Background

Intake of trans fatty acids (TFAs) from partially hydrogenated vegetable oil is associated with a variety of adverse outcomes, but little is known about the health effects of ruminant trans fats. Trans-vaccenic acid (TVA) is a naturally occurring TFA found in the fat of ruminants and in human dairy products. The present study was conducted to investigate the anticancer activity and underlying mechanisms of TVA on human nasopharyngeal carcinoma (NPC) 5-8F and CNE-2 cells.

Methods

A CCK8 assay was used to determine the effect of TVA and the Mcl-1 inhibitor S63845 on the proliferation of NPC cells. Apoptosis was measured using flow cytometry. Western blotting was used to detect the protein expression levels of factors associated with Bcl-2-family protein signaling and Akt signaling.

Results

TVA significantly inhibited cell proliferation in a dose-dependent manner. Mechanistic investigation demonstrated that TVA significantly decreased p-Akt levels and Bad phosphorylation on Ser-136 and Ser-112. More importantly, we discovered that the Mcl-1 inhibitor S63845 synergistically sensitized NPC cells to apoptosis induction by TVA.

Conclusion

TVA can inhibit NPC cell growth and induced apoptosis through the inhibition of Bad/Akt phosphorylation. The combined use of TVA and Mcl-1 inhibitors offers a potential advantage for nasopharyngeal cancer treatment.

High-Dose Static and Dynamic Intensity-Modulated Radiotherapy Combined with Chemotherapy for Patients with Locally Advanced Nasopharyngeal Carcinoma Improves Survival and Reduces Brainstem Toxicity

BACKGROUND Intensity-modulated radiotherapy (IMRT) is the standard treatment for patients with nasopharyngeal cancer (NPC). However, the dose-volume criteria for adjacent anatomically normal organs at risk (OARs) remain controversial. The aim of this study was to evaluate the effects of higher than conventional doses of static and dynamic IMRT on the locoregional control of NPC, patient survival, and brainstem radiation toxicity. MATERIAL AND METHODS Patients (n=186) with stage III and stage IVa NPC underwent high-dose static and dynamic IMRT treatment (68-76.96 Gy) with or without chemotherapy for 34-57 days. Overall survival (OS), the presence of distant metastases, and brainstem toxicity were assessed. One-year, three-year, and five-year follow-up was performed. RESULTS High-dose IMRT alone or in combination with chemotherapy resulted in a 100% objective response rate and significantly improved OS rates, with one-year, three-year, and five-year OS rates of 94.1%, 89.8%, and 88.2%, respectively. The local recurrence rate (17.6%), and distant metastasis to the lung, liver, and bone (17.2%), and mortality (n=22) were reduced. Chemotherapy was the only factor that was significantly correlated with patient survival. Brainstem toxicity was reduced in patients treated with static IMRT (0.07%) and dynamic IMRT (0.08%). There were 26 additional factors that were not found to significantly affect brainstem toxicity. CONCLUSIONS High-dose static or dynamic IMRT combined with chemotherapy improved survival and reduces distal metastasis with a very low occurrence of brainstem toxicity in patients with locally advanced NPC. These findings might provide therapeutic guidance for clinicians when planning optimal dose-volume IMRT parameters.

ABT-199-mediated inhibition of Bcl-2 as a potential therapeutic strategy for nasopharyngeal carcinoma

BACKGROUND

Aberrant overexpression of Bcl-2 protein has been detected in 80% of nasopharyngeal carcinoma (NPC), and Bcl-2 family proteins are implicated in both NPC oncogenesis and chemotherapy resistance. Previous studies have shown that while treatment of NPC cells with Bcl-2 family inhibitors alone is rarely effective, concomitant treatment with a cytotoxic reagent such as cisplatin can increase efficacy through a synergistic effect. The aim of the current work was to determine how we might increase the efficacy of Bcl-2 family inhibitors in the absence of cytotoxic reagents, which are associated with negative side effect profiles.

METHODS

We assessed cell proliferation in Bcl-2 high-expressing NPC cells by CCK-8 assay after treatment with the Bcl-2 inhibitor ABT-199 and/or the Mcl-1 inhibitor S63845. Apoptotic induction by ABT-199 was evaluated by Annexin V-FITC and PI double staining. We also evaluated Bcl-2 family protein expression (Bim, Mcl-1, Bcl-xL, Noxa) after treatment with ABT-199 by western blotting. Finally, xenografted Balb/c nude mice were used to test ABT-199 efficacy in vivo, H&E and immunohistochemistry assay were used to analyze tumor samples.

RESULTS

ABT-199 effectively induced NPC cell apoptosis in vitro and in the xenograft model. Following ABT-199 treatment in NPC cells, upregulation of Mcl-1 and Bcl-xL can lead to drug resistance, while concomitant Noxa overexpression partially neutralized the Mcl-1-caused resistance. Given that ABT-199 induces apoptosis in NPC cells through the Bcl-2/Noxa/Mcl-1 axis, treatment avenues further targeting this pathway should be promising. Indeed, the newly developed Mcl-1 inhibitor S63845 in combination with ABT-199 had a synergistic effect on NPC cell apoptosis.

CONCLUSION

Bcl-2 inhibition in NPC cells with ABT-199 triggers apoptosis through the Bcl-2/Noxa/Mcl-1 axis, and dual inhibition of the anti-apoptotic Bcl-2 family proteins Bcl-2 and Mcl-1 provided a strong synergistic effect without the need for adjunctive cytotoxic agent treatment with cisplatin.

Drug-like dietary vanilloids induce anticancer activity through proliferation inhibition and regulation of bcl-related apoptotic proteins

In this study, a series of 20 structurally similar vanilloids (Vn) were tested for their antiproliferative effects against 12 human cancer cells: human breast (MCF-7 and MDA-MB-231), cervical (HeLa), ovarian (Caov-3), lung (A549), liver (HepG2), colorectal (HT-29 and HCT116), nasopharyngeal (CNE-1 and HK-1), and leukemic (K562 and CEM-SS) cancer cells. Among all the tested vanilloids, Vn16 (6-shogaol) exhibited the most potent cytotoxic effects against human colorectal cancer cells (HT-29). The apoptotic induction effects exhibited by Vn16 on HT-29 cells were confirmed using dual staining fluorescence microscopy and enzyme-linked immunosorbent assay. The effects of Vn16 on regulation of 43 apoptotic-related markers were determined in HT-29. The results suggested that 8 apoptotic markers (caspase 8, BAD, BAX, second mitochondrial-derived activator, caspase 3, survivin, bcl-2, and cIAP-2) were either upregulated or downregulated. These results further support the chemopreventive properties of foods that contain vanilloids.

Camptothecin inhibits the progression of NPC by regulating TGF-β-induced activation of the PI3K/AKT signaling pathway

Nasopharyngeal carcinoma (NPC) is a type of cancer that is characterized by increased invasiveness, metastatic potential and tumor recurrence. Camptothecin has been demonstrated to exhibit anticancer activity. However, the potential underlying molecular mechanisms mediated by camptothecin in NPC cells remain elusive. In the present study, the efficacy of camptothecin for NPC was investigated in vitro and in vivo. Additionally, the potential signaling pathway mediated by camptothecin in NPC cells was also examined. The results indicated that the viability and aggressiveness of NPC cells were suppressed by camptothecin treatment in a dose-dependent manner. Camptothecin administration downregulated the expression levels of cell-cycle-associated proteins including cyclin 1, cyclin-dependent kinase (CDK)1 and CDK2 in NPC cells. Expression levels of migration-associated proteins including vimentin, fibronectin and epithelial cadherin were regulated by camptothecin treatment in NPC cells. Additionally, camptothecin inhibited the expression of transforming growth factor-β (TGF-β), phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT), whereas TGF-β overexpression abrogated camptothecin-mediated inhibition of PI3K and AKT expression and camptothecin-mediated inhibition of the viability and aggressiveness of NPC cells. Camptothecin significantly inhibited tumor growth and increased survival times in a mouse model of cancer. In conclusion, these results indicate that camptothecin treatment may inhibit the viability of NPC cells and aggressiveness by regulating the TGF-β-induced PI3K/AKT signaling pathways, which in turn may be a potential molecular target for the treatment of NPC.

Metastasis-associated protein 2 promotes the metastasis of non-small cell lung carcinoma by regulating the ERK/AKT and VEGF signaling pathways

Non-small cell lung carcinoma (NSCLC) is the most common cause of cancer‑associated mortality in the world and accounts for ~85% of human lung cancers. Metastasis‑associated protein 2 (MTA2) is a component of the histone deacetylase complex and serves a role in tumor progression; however, the mechanism through which MTA2 is involved in the progression of NSCLC remains unclear. The aim of the present study was to investigate the expression and function of MTA2 and the MTA2‑mediated signaling pathway in NSCLC cells. Expression of MTA2 and its target genes was analyzed in MTA2‑overexpressing and anti‑MTA2 antibody (AbMTA2)‑treated NSCLC cells, as well as growth, migration, invasion and apoptotic‑resistance. The inhibitory effects on tumor formation were analyzed using AbMTA2‑treated NSCLC cells and in a mouse model. Histological assessment was conducted to analyze the expressions levels of extracellular signal‑regulated kinase (ERK), RAC‑α serine/threonine protein kinase (AKT) and vascular endothelial growth factor (VEGF) in experimental tumors. Results of the present study demonstrated that MTA2 was overexpressed in NSCLC cells. The growth, migration and invasion of NSCLC cells were markedly inhibited by AbMTA2. In addition, it was observed that the ERK/AKT and VEGF signaling pathways were both upregulated in MTA2‑overexpressing NSCLC cells, and downregulated following silencing of MTA2 activation. ERK and AKT phosphorylation levels were downregulated in NSCLC cells and tumors following MTA2 silencing. The in vivo study demonstrated that tumor growth was markedly inhibited following siRNA‑MTA2 treatment. In conclusion, the results of the present study suggested that MTA2 silencing may significantly inhibit the growth and aggressiveness of NSCLC cells. Results from the present study indicated that the mechanism underlying the MTA2‑mediated invasive potential of NSCLC cells involved the ERK/AKT and VEGF signaling pathways, which may be a potential therapeutic target for the treatment of NSCLC.

Annexin A2-mediated cancer progression and therapeutic resistance in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a head and neck cancer with poor clinical outcomes and insufficient treatments in Southeast Asian populations. Although concurrent chemoradiotherapy has improved recovery rates of patients, poor overall survival and low efficacy are still critical problems. To improve the therapeutic efficacy, we focused on a tumor-associated protein called Annexin A2 (ANXA2). This review summarizes the mechanisms by which ANXA2 promotes cancer progression (e.g., proliferation, migration, the epithelial-mesenchymal transition, invasion, and cancer stem cell formation) and therapeutic resistance (e.g., radiotherapy, chemotherapy, and immunotherapy). These mechanisms gave us a deeper understanding of the molecular aspects of cancer progression, and further provided us with a great opportunity to overcome therapeutic resistance of NPC and other cancers with high ANXA2 expression by developing this prospective ANXA2-targeted therapy.

Impact of diabetes mellitus on the risk and survival of nasopharyngeal carcinoma: a meta-analysis

Background

Diabetes mellitus (DM) has been identified to be both a risk factor and a prognostic factor in a variety of malignancies, but its association with the risk and outcome of nasopharyngeal carcinoma (NPC) is still unclear. To elucidate this issue, we systematically reviewed the evidence concerning the association between DM status and NPC.

Materials and methods

We identified studies by a literature search of PubMed, Embase, and ISI Web of Knowledge through May 31, 2017, and by searching the reference lists of pertinent articles. Odds ratios (ORs) and hazard ratios (HRs) with 95% CIs were used to estimate the effect size. Heterogeneity across studies was evaluated by the Cochran’s Q and I² statistics.

Results

A total of nine studies were included. Four studies with a total sample size of 221,611 reported the effect of DM on NPC risk, and the other five studies with a sample size of 9,442 reported the impact of DM on survival in NPC patients. All included studies were retrospective, and mostly conducted in Asian populations. Meanwhile, condition of metformin usage was not considered in all studies. A pooled OR of 0.65 (95% CI: 0.43–0.98, P=0.04) revealed an inverse association between DM and NPC. Additionally, pooled analyses of studies investigating the prognosis value of DM revealed that preexisting DM had no effect on overall survival (HR =1.17, 95% CI: 0.94–1.46, P=0.16), local recurrence-free survival (HR =1.16, 95% CI: 0.80–1.67, P=0.44), and distant metastasis-free survival (HR =1.14, 95% CI: 0.92–1.40, P=0.22).

Conclusion

Our results suggested that DM patients might have decreased NPC risk, and have little impact on prognosis of NPC patients. This conclusion should be limited to Asian population. Our results also suggest that more attention should be paid to metformin medication in further studies in order to clarify whether the effects of DM on NPC risk and prognosis are influenced by the anticancer effect of metformin.

CFTR is a potential marker for nasopharyngeal carcinoma prognosis and metastasis

While there is an increasing interest in the correlation of cystic fibrosis transmembrane conductance regulator (CFTR) and cancer incidence, the role of CFTR in nasopharyngeal carcinoma (NPC) development remains unknown. In this study, we aimed to explore the prognostic value of CFTR in NPC patients. The expression of CFTR was determined in NPC cell lines and tissues. Statistical analysis was utilized to evaluate the correlation between CFTR expression levels and clinicopathological characteristics and prognosis in 225 cases of NPC patients. The results showed that CFTR was down-regulated in NPC tissues and cell lines. Low expression of CFTR was correlated with advanced stage (p = 0.026), distant metastasis (p < 0.001) and poor prognosis (p < 0.01). Multivariate analysis identified CFTR as an independent prognostic factor (p = 0.003). Additionally, wound healing and transwell assays revealed that overexpression of CFTR inhibited NPC cell migration and invasion, whereas knockdown of CFTR promoted cell migration and invasion. Thus, the current study indicates that CFTR, as demonstrated to play an important role in tumor migration and invasion, may be used as a potential prognostic indicator in NPC.

Simultaneously Targeting Bcl-2 and Akt Pathways Reverses Resistance of Nasopharyngeal Carcinoma to TRAIL Synergistically

Aims and Background

Despite progress in treatment techniques, the five-year survival rate of nasopharyngeal carcinoma (NPC) is disappointing. Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) can selectively induce apoptosis in most tumor cells while sparing normal cells. Given the antiapoptotic functions of Bcl-2 and Akt, we examined the effects of targeting these pathways alone or simultaneously on TRAIL apoptosis in NPC cell lines.

Methods and Study Design

We first tested the cytotoxic effect of TRAIL and the expression of death receptors, Bcl-2, Akt, and p-Akt on four NPC cell lines by MTT and Western blotting, respectively. Small interfering RNAs (siRNAs) targeting Bcl-2 and PI3–K inhibitor (LY294002) were used alone or combined with TRAIL in the cell lines and cytotoxicity was examined by MTT. Apoptosis rates, mitochondrial transmembrane potential, and apoptotic pathway signals were detected by flow cytometric analysis, DiOC6(3) assays, and Western blotting after the various combination treatments on CNE-2, the cell line that was most resistant to TRAIL.

Results

Although no direct correlation between the sensitivity to TRAIL and the relative expression levels of Bcl-2 and activated Akt was found in the NPC cell lines examined, siRNA mediated the downregulation of Bcl-2 and LY294002-induced inactivation of Akt, increasing the sensitivity of all examined NPC cell lines to TRAIL. Synergistic enhancement of TRAIL-mediated cytotoxicity was observed in combination treatment of Bcl-2 siRNA and LY294002 compared to cells treated with each treatment alone. The synergistic effects were mediated through increased apoptotic signaling of the mitochondrial pathway, as was evident from the more increased mitochondrial depolarization, activation of caspase-9 and caspase-3, and suppression of XIAP.

Conclusions

This study provides proof of principle that TRAIL combined with simultaneously targeting the Bcl-2 and Akt signaling pathways may have potential as a novel future treatment strategy for NPC.

FM807, a curcumin analogue, shows potent antitumor effects in nasopharyngeal carcinoma cells by heat shock protein 90 inhibition

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy usually associated with overexpression of both epidermal growth factor receptor (EGFR) and β-catenin. FM807 is a novel curcumin analogue with antitumor activity against both poorly and well-differentiated NPC cell lines as well as good selectivity for tumor cells. FM807 actions were shown to include inhibition of cell growth, induction of necrotic/late apoptotic cell death, and G1 arrest in NPC cells. Crucially, it exhibited potent antitumor effects both in vitro and in vivo. Binding of FM807 to the N-terminus of Hsp90 disrupted Hsp90/client complexes, resulting in degradation of the Hsp90 client protein EGFR and inhibition of the downstream Raf/MEK/ERK and PI3K/AKT pathway. FM807 also depleted levels of the intranuclear transcription factors β-catenin, Cyclin D1 and c-Myc levels by inhibiting Hsp90 chaperoned nuclear transport. In conjunction with its low toxicity in NPC xenograft mice, these results provide a sound preclinical basis for further development of FM807 as a novel therapeutic agent in the treatment of NPC.

Therapeutic effect of TMZ-POH on human nasopharyngeal carcinoma depends on reactive oxygen species accumulation

Nasopharyngeal carcinoma (NPC) is a common head and neck malignancy without efficient chemotherapeutic agents for it. In our current study, we demonstrated the cytotoxicity effects of a newly patented compound temozolomide–perillyl alcohol (TMZ-POH) on NPC in vitro and in vivo, and the possible mechanisms involved. Human NPC cell lines CNE1, CNE2, HNE2, and SUME-α were treated with control (DMSO), TMZ, POH, TMZ plus POH, and TMZ-POH. Our data indicated that TMZ-POH could inhibit NPC cell proliferation, cause G₂/M arrest and DNA damage. TMZ-POH triggered apoptosis in NPC cells via significant activation of caspase-3 and poly(ADP-ribose) polymerase (PARP). Importantly, TMZ-POH-induced cell death was found to be associated with (i) the loss of inner mitochondrial membrane potential (ΔΨm) and release of mitochondrial Cytochrome c, (ii) the increase in ROS generation, and (iii) the activation of stress-activated protein kinases (SAPK)/c-Jun N-terminal kinases (JNK) signaling pathway. The generation of ROS in response to TMZ-POH seems to play a crucial role in the cell death process since the blockage of ROS production using the antioxidant N-acetyl-L-cysteine or catalase reversed the TMZ-POH-induced JNK activation, DNA damage, and cancer cell apoptosis. These results provide the rationale for further research and preclinical investigation of the antitumor effect of TMZ-POH against human NPC.

Ionizing radiation promotes advanced malignant traits in nasopharyngeal carcinoma via activation of epithelial-mesenchymal transition and the cancer stem cell phenotype

Post-irradiation residual mass and recurrence always suggest a worse prognosis for nasopharyngeal carcinoma (NPC). Our study aimed to investigate the malignant behaviors of post-irradiation residual NPC cells, to identify the potential underlying mechanisms and to search for appropriate bio-targets to overcome this malignancy. Two NPC cell lines were firstly exposed to 60 Gy irradiation, and residual cells were collected. In our previous study, colony formation assay detected the radioresistance of these cells. Here, the CCK-8 assay examined the cell sensitivity to paclitaxel and cisplatin. Wound-healing and Transwell assays were performed to investigate cell motility and invasion capabilities. Inverted phase-contrast microscopy was used to observe and photograph the morphology of cells. Expression levels of epithelial-mesenchymal transition (EMT)-related proteins were detected by western blot assay in NPC cells and tissues. The mRNA levels of cancer stem cell (CSC)-related genes were detected via qRT-PCR. The results revealed that residual NPC cells exhibited enhanced radioresistance and cross-resistance to paclitaxel and cisplatin. Higher capacities of invasion and migration were also observed. An elongated morphology with pseudopodia formation and broadening in the intercellular space was observed in the residual cells. Downregulation of E-cadherin and upregulation of vimentin were detected in the residual NPC cells and tissues. CSC-related Lgr5 and c-myc were significantly upregulated in the CNE-2-Rs and 6-10B-Rs radioresistance cells. Higher proportions of Lgr5+ cells were observed in radioresistant cells via immunofluorescent staining and flow cytometry. In conclusion, our study demonstrated that residual NPC cells had an advanced malignant transition and presented with both EMT and a CSC phenotype. This provides a possible clue and treatment strategy for advanced and residual NPC.

Long-Term Outcomes of Nasopharyngeal Carcinoma in 148 Children and Adolescents

The aim of this study was to investigate the survival and long-term morbidities of nasopharyngeal carcinoma (NPC) in children and adolescents.We retrospectively reviewed children and adolescents with NPC treated at Sun Yat-sen University Cancer Center from February 1991 to October 2010, where the prognostic factors and long-term effects of therapy were analyzed.A total of 148 patients were identified. The median age was 15 years old (range, 5-18 years) and the male to female ratio was 3.6:1. Most of the tumor histopathology was undifferentiated nonkeratinizing carcinoma (97.3%). The number of patients staged with IVa, IVb, IVc, III, and II were 45 (30.4%), 12 (8.1%), 5 (3.4%), 70 (47.3%), and 16 (10.8%), respectively. For the whole series with a median follow-up of 81 months (range, 6-282 months), the 5-year overall survival (OS) and disease-free survival (DFS) ratios were 79.3% and 69.7%, respectively. We observed significant differences in the 5-year OS (81.1% vs 25.0%, P = 0.002) and the DFS rates (72.2% vs 0.0%, P = 0.000) between patients with stage II to IVb disease and stage IVc disease. For patients with stage II, III, IVa, and IVb disease, we found a high radiation dose (dose > 66 Gy to the primary lesion) would not significantly improve the survival compared to the sub-high radiation dose group (dose = 60-66 Gy to the primary lesion), even considering the type of radiation therapy technologies. However, the incidences of sequelae (grades I-IV) in patients with high radiation dose were apparently higher than those in patients with low radiation dose.Considering the late sequelae, a dose of 60 to 66 Gy to the primary lesions seems to be enough for children and adolescents with NPC.

Epstein-Barr virus infection and nasopharyngeal carcinoma: the other side of the coin

Oncogenic viruses may have a significant impact on the therapeutic management of several malignancies besides their well-known role in tumor pathogenesis. Epstein-Barr virus (EBV) induces neoplastic transformation of epithelial cells of the nasopharynx by various molecular mechanisms mostly involving activation of oncogenes and inactivation of tumor-suppressor genes. EBV infection can also induce the expression of several immunogenic peptides on the plasma membrane of the infected cells. Importantly, these virus-related antigens may be used as targets for antitumor immunotherapy-based treatment strategies. Two different immunotherapy strategies, namely adoptive and active immunotherapy, have been developed and strongly improved in the recent years. Furthermore, EBV infection may influence the use of targeted therapies for nasopharyngeal carcinoma (NPC) considering that the presence of EBV can induce important modifications in cell signaling. As an example, latent membrane protein type 1 is a viral transmembrane protein mainly involved in the cancerogenesis process, which can also mediate overexpression of the epidermal growth factor receptor (EGFR) in NPC cells, rendering them more sensitive to anti-EGFR therapy. Finally, EBV may induce epigenetic changes in the infected cells, such as DNA hypermethylation and histone deacetylation, that can sustain tumor growth and can thus be considered potential targets for novel therapies. In conclusion, EBV infection can modify important biological features of NPC cells, rendering them more vulnerable to both immunotherapy and targeted therapy.

Identification and analysis of the promoter region of the STGC3 gene

INTRODUCTION

Nasopharyngeal carcinoma (NPC) is a common malignant tumor of the head and neck. The STGC3 gene is related to development of nasopharyngeal cancer. The aim of this study is to explore the promoter region of the STGC3 gene.

MATERIAL AND METHODS

The bioinformatic technique was applied to predict its promoter region and construct the gene promoter region luciferase for the gene vector and transfection of the human embryonic kidney epithelial 293T cell line, human nasopharyngeal carcinoma CNE2 cell line and immortalized nasopharyngeal epithelial NP69 cell line. The recombinant plasmid pGL3-en283, pGL3-en281, pGL3-en571, empty plasmid pGL3-control, negative control pGL3-enhance and internal control of marine intestine luciferase expression vector pRL-SV40 were transfected into NP69 cells, 293T cells and CNE2 cells. Dual luciferase activity detection showed luciferase luminescence values and marine intestine luciferase luminescence values. Relative luciferase activity (RLA) in each cell was calculated.

RESULTS

We observed strong promoter activity of plasmid pGL3-en283, pGL3-en281 and pGL3-en571 in NP69, 293T and CNE2 cells compared with the negative control pGL3-enhance plasmid. Among them, pGL3-en281 showed the strongest promoter activity, and these three kinds of recombinant plasmids showed stronger promoter activity in 293T cells than in CNE2 cells.

CONCLUSIONS

The pGL3-en281 plasmid showed stronger promoter activity than pGL3-en571 in the three cells, indicating that -11048 bp to -653 bp might be the core promoter region.

Nasopharyngeal carcinoma

Nasopharyngeal carcinoma is uncommon in the United States, with only 0.2 to 0.5 cases per 100,00 people; this is in contrast to southern China and Hong Kong, where the incidence is 25 to 50 per 100,000 people. There is a potential link between Epstein-Barr virus and the development of nasopharyngeal carcinoma. Radiotherapy alone as a single modality leads to similar 10-year survival rates in United States, Denmark, and Hong Kong (34%, 37%, and 43%, respectively). Multiple studies have shown an advantage to concurrent chemoradiation in the treatment of advanced disease. Radiation therapy remains the mainstay of salvage therapy, and modern techniques have allowed clinicians to achieve adequate local control without excessive toxicity.

Safety and efficacy study of nasopharyngeal cancer stem cell vaccine

In this trial, nasopharyngeal cancer stem cells (CSCs) were separated and cultured to produce a vaccine; its safety and efficacy were prospectively evaluated in low-, medium-, and high-dose groups. Between April and September 2014, we enrolled 90 patients who met the enrolment criteria, and assigned them to three groups (n=30). Throughout the trial, injection site reaction was the most common reaction (81%), and fever was least common (31%); however, there was no difference among the three groups. When the immune responses pre- and post-vaccination were compared, we found that the CSC-specific and -nonspecific response in the medium- and high-dose groups were both significantly enhanced. This study is the first clinical trial of a nasopharyngeal CSC vaccine and preliminarily proves its safety and efficacy.

Therapeutic implications of Epstein-Barr virus infection for the treatment of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is highly endemic in certain regions including the People’s Republic of China and Southeast Asia. Its etiology is unique and multifactorial, involving genetic background, epigenetic, and environment factors, including Epstein–Barr virus (EBV) infection. The presence of EBV in all tumor cells, aberrant pattern of antibodies against EBV antigens in patient sera, and elevated viral DNA in patient circulation as well as nasopharyngeal site underline the role of EBV during NPC development. In NPC tumors, EBV expresses latency type II, where three EBV-encoded proteins, Epstein–Barr nuclear antigen 1, latent membrane protein 1 and 2 (LMP1, 2), are expressed along with BamH1-A rightward reading frame 1, Epstein–Barr virus-encoded small nuclear RNAs, and BamH1-A rightward transcripts. Among all encoded proteins, LMP1 plays a central role in the propagation of NPC. Standard treatment of NPC consists of radiotherapy with or without chemotherapy for early stage, concurrent chemoradiotherapy in locally advanced tumors, and palliative systemic chemotherapy in metastatic disease. However, this standard care has limitations, allowing recurrences and disease progression in a certain proportion of cases. Although the pathophysiological link and molecular process of EBV-induced oncogenesis are not fully understood, therapeutic approaches targeting the virus may increase the cure rate and add clinical benefit. The promising results of early phase clinical trials on EBV-specific immunotherapy, epigenetic therapy, and treatment with viral lytic induction offer new options for treating NPC.

Hotspot mutations in common oncogenes are infrequent in nasopharyngeal carcinoma

Oncogene mutations contribute to carcinogenesis and can provide potential therapeutic targets for clinical anticancer management. However, oncogene mutation patterns in nasopharyngeal carcinoma (NPC) have yet to be fully elucidated. To gain insight into mutation patterns in NPC, a high-throughput OncoCarta panel assay was used to determine 238 hotspot mutations across 19 common oncogenes in 8 NPC cell lines and 160 NPC patient samples from southern China. Statistical analyses were further conducted to identify associations between oncogene mutations and selected clinicopathological characteristics. In total, we identified 24 mutations across 11 oncogenes in 17 (10.6%) NPC patients. Four patients exhibited mutations in at least one oncogene. We also identified a PIK3CA H1047R mutant in 7 NPC cell lines. In addition, oncogene mutations showed no correlation with either risk habits (smoking and drinking) or other clinical characteristics except for TNM stage. KIT mutations were associated with poorer overall and relapse-free survival. Furthermore, KIT mutations together with age and N stage were independent prognostic factors in NPC. Taken together, the present study is the first report on mutations in multiple oncogenes in NPC. We found that hotspot oncogene mutations are infrequent in NPC patients from southern China. The lack of hotspot mutations requires a comprehensive characterization of gene mutations in NPC for developing new therapeutic targets in the future.

Optimal management of a patient with recurrent nasopharyngeal carcinoma

Nasopharyngeal carcinoma is rare in western countries, accounting for less than 1% of all malignancies. Despite prognosis is satisfactory for newly diagnosed, non-metastatic disease, management of recurrent disease is challenging, with a survival expectancy of approximately 6 mo with the use of chemotherapy as the sole salvage treatment. We report a case of recurrent nasopharyngeal carcinoma treated with a combination of chemotherapy, radiotherapy and surgery in the context of a multidisciplinary approach. A durable complete response was achieved.