Eight-Signature Classifier for Prediction of Nasopharyngeal Carcinoma Survival

Prognostic nomogram for patients with Nasopharyngeal Carcinoma incorporating hematological biomarkers and clinical characteristics

Predictive models for survival prediction in individual cancer patients following the tumor, node, and metastasis (TNM) staging system are limited. The survival rates of patients who share TNM stage diseases are diversified. Therefore, we established a nomogram in which hematological biomarkers and clinical characteristics for predicting the overall survival (OS) of nasopharyngeal carcinoma (NPC) patients were incorporated. The clinicopathological and follow-up data of 690 NPC patients who were histologically diagnosed histologically at the Sun Yat-sen University Cancer Center between July 2007 and December 2011 were retrospectively reviewed. Data was randomly divided into primary (n = 460) and validation groups (n = 230). Cox regression analysis was used to identify prognostic factors for building the nomogram in primary cohorts. The predictive accuracy and discriminative ability of the nomogram were measured by the concordance index (C-index) and decision curve, and were compared with the TNM staging system, Epstein-Barr virus DNA copy numbers (EBV DNA), or TMN stage plus EBV DNA. The results were internally validated by assessment of discrimination and calibration using the validation cohorts at the same institution. Independent factors selected into the nomogram for OS included age [hazard ratio (HR): 1.765; 95% confidence interval (CI): 1.008-3.090)], TNM stage (HR: 1.899; 95% CI: 1.023-3.525), EBV DNA (HR: 1.322; 95% CI: 1.087-1.607), lactate dehydrogenase level (LDH) (HR: 1.784; 95% CI: 1.032-3.086), high sensitivity C-reactive protein (hs-CRP) (HR: 1.840; 95% CI: 1.039-3.258), high-density lipoprotein cholesterol (HDL-C) (HR: 0.503; 95% CI: 0.282-0.896), hemoglobin (HGB) (HR: 0.539; 95% CI: 0.309-0.939) and lymphocyte to lymphocyte ratio (LMR) (HR:0.531; 95% CI: 0.293-0.962). The C-index in the primary cohort and validation cohort were 0.800 and 0.831, respectively, and were statistically higher when compared to C-index values for TNM stage (0.672 and 0. 716), EBV DNA (0.668 and 0.688), and TNM stage+ EBV DNA (0. 732 and 0. 760), P < 0.001 for all. Moreover, the decision curve analyses demonstrated that the nomogram model had a higher overall net benefit compared to the TNM staging system, EBV DNA and TNM stage+ EBV DNA. Next, patients were divided into three distinct risk groups for OS based on total points (TPs) of the nomogram: a low-risk group (TPs ≤ 19.0), an intermediate risk group (19.0 < TPs ≤ 25.5) and a high risk group (TPs > 25.5), respectively. The nomogram predicting prognosis generated for NPC patients had a higher predictive power compared to the TNM staging system, EBV DNA, and TNM stage+ EBV DNA.

High-density lipoprotein cholesterol as a predictor of poor survival in patients with nasopharyngeal carcinoma

Purpose

We aimed to assess the prognostic value of pretreatment high density lipoprotein cholesterol (HDL-C) levels in patients with nasopharyngeal carcinoma (NPC) and investigate the possible biological effects of these lipoproteins on NPC cells in vitro.

Experimental Design

We examined the prognostic value of pretreatment HDL-C levels in 2443 patients with non-metastatic NPC from three independent institutions. The Cox proportional hazard model and log-rank test were used to analyze the correlation between HDL-C levels and overall survival (OS). Cell growth, colony formation, and apoptotic assays were used to determine the biological functions of HDL on NPC cells in vitro. All of the statistical tests were two-sided.

Results

OS was decreased in patients with high pretreatment HDL-C levels compared with those with low HDL-C levels (P < 0.05). Similarly, a decreased OS was noted in advanced stage (stage III-IV), NPC patients with high pretreatment HDL-C levels (P < 0.01). Multivariate analyses indicated that HDL-C was an independent prognostic factor associated with shorter OS in training cohorts. These findings were confirmed in both independent validation cohorts (P < 0.01). In vitro experiments demonstrated that HDL could increase cell proliferation, invasion, and colony formation, which were largely dependent on the expression of its receptor SR-B1. Finally, HDL could enhance chemoresistance by protecting cancer cells from apoptosis.

Conclusions

Pretreatment HDL-C is a poor prognostic factor for patients with NPC. This effect may be associated with the ability of HDL to enhance proliferation, colony formation, migration, and chemoresistance in NPC cells.

Role of regenerating gene IA expression on local invasion and survival in nasopharyngeal carcinoma

BACKGROUND

Regenerating gene IA (REGIA) plays an important role in tissue regeneration and tumors prognosis of epithelium origin. However, the role of REGIA in nasopharyngeal carcinoma (NPC) is unclear. This study aims to investigate the expression and function of REG1A in NPC.

RESULTS

We have found that there was 63 patients with REGIA positive expression of 155 patients in this study (40.65%). The positive expression rate of REGIA was 30.50, 44.44 and 47.83% in stage T2, T3 and T4 patients, respectively. The REGIA expression was significantly difference in T2 and T4 stage tumors or T2 and T3-T4 stage. The positive expression rate of REGIA was found to be higher in patients with cervical lymph node persistence than those with cervical lymph node complete regression. Patients with negative REGIA expression had a better overall survival and free survival than those with REGIA positive expression. In addition, according to the univariate and multivariate analysis, the REGIA expression was an independent adverse prognostic factor for NPC patients.

CONCLUSION

REGIA expression was a useful biomarker in NPC patients for assessing T stage and survival.

Nasopharyngeal carcinoma super-enhancer-driven ETV6 correlates with prognosis

Nasopharyngeal carcinoma (NPC) most frequently occurs in southern China and southeast Asia. Epidemiology studies link NPC to genetic predisposition, Epstein-Barr virus (EBV) infection, and environmental factors. Genetic studies indicate that mutations in chromatin-modifying enzymes are the most frequent genetic alterations in NPC. Here, we used H3K27ac chromatin immune precipitation followed by deep sequencing (ChIP-seq) to define the NPC epigenome in primary NPC biopsies, NPC xenografts, and an NPC cell line, and compared them to immortalized normal nasopharyngeal or oral epithelial cells. We identified NPC-specific enhancers and found these enhancers were enriched with nuclear factor κB (NF-κB), IFN-responsive factor 1 (IRF1) and IRF2, and ETS family members ETS1 motifs. Normal cell-specific enhancers were enriched with basic leucine zipper family members and TP53 motifs. NPC super-enhancers with extraordinarily broad and high H3K27ac signals were also identified, and they were linked to genes important for oncogenesis including ETV6. ETV6 was also highly expressed in NPC biopsies by immunohistochemistry. High ETV6 expression correlated with a poor prognosis. Furthermore, we defined the EBV episome epigenetic landscapes in primary NPC tissue.

Systemic immune-inflammation index predicts the clinical outcome in patients with nasopharyngeal carcinoma: a propensity score-matched analysis

Systemic immune-inflammation index (SII), based on peripheral lymphocyte, neutrophil, and platelet counts, was recently investigated as a prognostic marker in several tumors. However, SII has not been reported in nasopharyngeal carcinoma (NPC). We evaluated the prognostic value of the SII in 327 patients with NPC. Univariate and multivariate analyses were calculated by the Cox proportional hazards regression model. The time-dependent receiver operating characteristics (ROC) curve was used to compare the discrimination ability for OS. PSM (propensity score matching) was carried out to imbalance the baseline characteristics. Our results showed that SII, PLR, NLR and MLR were all associated with OS in NPC patients in the Kaplan-Meier survival analysis. SII (HR: 2.26; 95% CI: 1.40-3.66; P=0.001), NLR (HR: 1.66; 95% CI: 1.08-2.53; P=0.020), and MLR (HR: 1.99; 95% CI: 1.17-3.39; P=0.011) were identified to be the independent prognostic factors. The AUC for SII was bigger than NLR, PLR and MLR for predicting survival in patients with NPC in 3 or 5-years. In the PSM analysis, SII remained an independent predictor for OS in NPC patients (HR=2.08, CI 1.22-3.55, P=0.007). SII is a novel, simple and inexpensive prognostic predictor for patients with NPC. The prognostic value of SII is superior to PLR, NLR and MLR.

M2-polarized tumour-associated macrophages in stroma correlate with poor prognosis and Epstein-Barr viral infection in nasopharyngeal carcinoma

OBJECTIVES

To assess the relationships between CD163 expression, localization of CD163⁺ macrophages, clinicopathological features and prognosis of NPC.

METHODS

A total of 110 cases of NPC specimens and 80 cases of nasopharyngitis specimens were analysed for CD163 expression by immunohistochemistry and EBERs expression in situ hybridization.

RESULTS

CD163 + macrophages in the tumour stroma were positively correlated with the tumour and nodal stage. Higher expression of Epstein-Barr virus-encoded RNAs (EBERs) in the nuclei of tumour cells was associated with higher density of CD163 + macrophages in the tumour stroma. More importantly, greater infiltration of CD163 + macrophages in the tumour stroma was associated with poor overall survival (OS) and poor progression-free survival (PFS). Multivariate analysis revealed that the density of CD163⁺ macrophages in the tumour stroma may be an independent risk factor for NPC prognosis.

CONCLUSIONS

Increased infiltration of CD163⁺ macrophages in the tumour stroma correlates with worse outcomes and with Epstein-Barr virus (EBV) infection status of tumour cells in nasopharyngeal carcinoma (NPC).

Radiomics Features of Multiparametric MRI as Novel Prognostic Factors in Advanced Nasopharyngeal Carcinoma

Purpose: To identify MRI-based radiomics as prognostic factors in patients with advanced nasopharyngeal carcinoma (NPC).Experimental Design: One-hundred and eighteen patients (training cohort: n = 88; validation cohort: n = 30) with advanced NPC were enrolled. A total of 970 radiomics features were extracted from T2-weighted (T2-w) and contrast-enhanced T1-weighted (CET1-w) MRI. Least absolute shrinkage and selection operator (LASSO) regression was applied to select features for progression-free survival (PFS) nomograms. Nomogram discrimination and calibration were evaluated. Associations between radiomics features and clinical data were investigated using heatmaps.Results: The radiomics signatures were significantly associated with PFS. A radiomics signature derived from joint CET1-w and T2-w images showed better prognostic performance than signatures derived from CET1-w or T2-w images alone. One radiomics nomogram combined a radiomics signature from joint CET1-w and T2-w images with the TNM staging system. This nomogram showed a significant improvement over the TNM staging system in terms of evaluating PFS in the training cohort (C-index, 0.761 vs. 0.514; P < 2.68 × 10^-9). Another radiomics nomogram integrated the radiomics signature with all clinical data, and thereby outperformed a nomogram based on clinical data alone (C-index, 0.776 vs. 0.649; P < 1.60 × 10^-7). Calibration curves showed good agreement. Findings were confirmed in the validation cohort. Heatmaps revealed associations between radiomics features and tumor stages.Conclusions: Multiparametric MRI-based radiomics nomograms provided improved prognostic ability in advanced NPC. These results provide an illustrative example of precision medicine and may affect treatment strategies. Clin Cancer Res; 23(15); 4259-69. ©2017 AACR.

Prognostic and Predictive Value of p21-activated Kinase 6 Associated Support Vector Machine Classifier in Gastric Cancer Treated by 5-fluorouracil/Oxaliplatin Chemotherapy

To determine whether p21-activated Kinase (PAK) 6 is a prognostic and predictive marker in gastric cancer (GC) and to construct a classifier that can identify a subset of patients who are highly sensitive to 5-fluorouracil/oxaliplatin chemotherapy. We retrospectively analyzed the expression levels of PAK6, cyclooxygenase 2, p21^WAF1, Ki-67, excision repair cross-complementing gene 1, and thymidylate synthase in 242 paraffin-embedded GC specimens of the training cohort by immunohistochemistry. Then, we used support vector machine (SVM)–based methods to develop a predictive classifier for chemotherapy (chemotherapy score – CS-SVM classifier). Further validation was performed in an independent cohort of 279 patients. High PAK6 expression was associated with poor prognosis and increased chemoresistance to 5-FU/oxaliplatin chemotherapy. The CS-SVM classifier distinguished patients with stage II and III GC into low- and high-CS-SVM groups, with significant differences in the 5-year disease-free survival (DFS) and overall survival (OS) in chemotherapy patients. Moreover, chemotherapy significantly prolonged the DFS and OS of the high CS-SVM patients in the training and validation cohorts. In conclusion, PAK6 was an independent prognostic factor and increased chemoresistance. The CS-SVM classifier distinguished a subgroup of stage II and III patients who would highly benefit from chemotherapy, thus facilitating patient counseling and individualizing the management.

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p21-activated Kinase 6 was a predictive biomarker and increased chemoresistance to 5-FU/oxaliplatin chemotherapy.

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The CS-SVM classifier distinguished a subgroup of stage II and III patients who would highly benefit from chemotherapy.

PAK6 was an independent prognostic factor and increased chemoresistance. The chemotherapy score – support vector machine classifier distinguished a subgroup of stage II and III patients who would highly benefit from chemotherapy. The model maybe useful for patient counseling and individualized treatment decision-making.

Plasma Epstein-Barr viral DNA complements TNM classification of nasopharyngeal carcinoma in the era of intensity-modulated radiotherapy

BACKGROUND

The objective of this study is to verify the prognostic value of pretreatment plasma Epstein-Barr viral deoxyribonucleic acid (pEBV DNA) levels in nasopharyngeal carcinoma (NPC) patients to complement TNM classification based on the application of the intensity-modulated radiotherapy (IMRT) technique.

METHODS

In total, 1467 patients staged at I-IVa-b (M0) and treated with IMRT were retrospectively analyzed at our cancer center from January 2007 to December 2010. Patient survival among different stages and EBV DNA levels were compared.

RESULTS

Outcome analyses of different stages and EBV DNA levels revealed that patients in stages II-III with low EBV DNA levels had similar survival as that of patients in stages IVa-b with low EBV DNA (5-yr overall survival (OS), 94.7% vs. 92.9% (P = 0.141), progression failure-free survival (PFS), 87.2% vs. 89.0% (P = 0.685), distant metastasis failure-free survival (DMFS), 93.5% vs. 92.4% (P = 0.394) and locoregional failure-free survival (LRFS), 93.8% vs. 96.3% (P = 0.523)). Conversely, patients in stages II-III with high EBV DNA had better survival than patients in stages IVa-b with high EBV DNA (5-yr OS, 82.7% vs. 71.7% (P = 0.001), PFS, 70.7% vs. 66.2% (P = 0.047), DMFS, 79.6% vs. 74.8% (P = 0.066) and LRFS, 89.3% vs. 87.6% (P = 0.425)) but poorer survival than patients in stages IVa-b with low EBV DNA (5-yr OS, 82.7% vs. 92.9% (P = 0.025), PFS, 70.7% vs. 89.0, (P < 0.001), DMFS, 79.6% vs. 92.4%, (P = 0.001), LRFS, 89.3% vs. 96.3%, (P = 0.022)).

CONCLUSIONS

pEBV DNA is a strong prognostic factor for patients with NPC when complemented with TNM staging in the era of IMRT application.

Novel biomarkers of nasopharyngeal carcinoma metastasis risk identified by reverse phase protein array based tumor profiling with consideration of plasma Epstein-Barr virus DNA load

PURPOSE

In patients with Epstein-Barr virus (EBV) associated nasopharyngeal carcinoma (NPC), intertumor heterogeneity causes interpatient heterogeneity in the risk of distant metastasis. We aimed to identify novel biomarkers of metastasis risk using reverse phase protein array (RPPA) profiling of NPC patients at risk for metastasis and considering plasma EBV DNA load.

EXPERIMENTAL DESIGN

A total of 98 patients with NPC with and without metastasis after treatment, matched with respect to clinical parameters, are enrolled. Total protein expression is measured by RPPA, and protein functions are analyzed by pathway bioinformatics.

RESULTS

The RPPA analysis revealed a profile of 70 proteins that are differentially expressed in metastatic and nonmetastatic tumors. Plasma EBV DNA load after treatment correlated with protein expression level better than plasma EBV DNA load before treatment did. The biomarkers of NPC metastasis identified by proteomics regulate signaling pathways involved in cell cycle progression, apoptosis, and epithelial-mesenchymal transition. The authors identified 26 biomarkers associated with 5-year distant failure-free survival in univariate analysis; five biomarkers remained significant in multivariate analysis.

CONCLUSIONS AND CLINICAL RELEVANCE

A comprehensive RPPA profiling study is warranted to identify novel metastasis-related biomarkers and further examine the activation state of signaling proteins to improve estimation of metastasis risk for patients with EBV-associated NPC.

A chemotherapy response classifier based on support vector machines for high-grade serous ovarian carcinoma

Long-term outcome of high-grade serous epithelial ovarian carcinoma (HGSOC) remains poor as a result of recurrence and the emergence of drug resistance. Almost all the patients were given the same platinum-based chemotherapy after debulking surgery even though some of them are naturally resistant to the first-line chemotherapy. No method could verify this part of patients right after the surgery currently. In this study, we used 156 paraffin-embedded high-grade HGSOC specimens for immunohistochemical analysis with 37 immunology markers, and association between the expression levels of these markers and the chemoresponse were evaluated. A support vector machine (SVM)-based HGSOC prognostic classifier was then established, and was validated by a 95-patient independent cohort. The classifier was strongly predictive of chemotherapy resistance, and divided patients into low- and high-risk groups with significant differences progression-free survival (PFS) and overall survival (OS). This classifier may provide a potential way to predict the chemotherapy resistance of HGSOC right after the surgery, and then allow clinicians to make optimal clinical decision for those potentially chemoresistant patients. The potential clinical application of this classifier will benefit those patients with primary drug resistance.

Revalidation of a prognostic score model based on complete blood count for nasopharyngeal carcinoma through a prospective study

OBJECTIVE

In our previous work, we incorporated complete blood count (CBC) into TNM stage to develop a new prognostic score model, which was validated to improve prediction efficiency of TNM stage for nasopharyngeal carcinoma (NPC). The purpose of this study was to revalidate the accuracy of the model, and its superiority to TNM stage, through data from a prospective study.

METHODS

CBC of 249 eligible patients from the 863 Program No. 2006AA02Z4B4 was evaluated. Prognostic index (PI) of each patient was calculated according to the score model. Then they were divided by the PI into three categories: the low-, intermediate-and high-risk patients. The 5-year disease-specific survival (DSS) of the three categories was compared by a log-rank test. The model and TNM stage (7th edition) were compared on efficiency for predicting the 5-year DSS, through comparison of the area under curve (AUC) of their receiver-operating characteristic curves.

RESULTS

The 5-year DSS of the low-, intermediate-and high-risk patients were 96.0%, 79.1% and 62.2%, respectively. The low-and intermediate-risk patients had better DSS than the high-risk patients (P<0.001 and P<0.005, respectively). And there was a trend of better DSS in the low-risk patients, compared with the intermediate-risk patients (P=0.049). The AUC of the model was larger than that of TNM stage (0.726 vs. 0.661, P=0.023).

CONCLUSIONS

A CBC-based prognostic score model was revalidated to be accurate and superior to TNM stage on predicting 5-year DSS of NPC.

An inflammatory biomarker-based nomogram to predict prognosis of patients with nasopharyngeal carcinoma: an analysis of a prospective study

Chronic inflammation plays an important role in tumor progression. The aim of this analysis was to evaluate whether inflammatory biomarkers such as the Glasgow prognostic score (GPS), the neutrophil‐lymphocyte ratio (NLR), the platelet‐lymphocyte ratio (PLR), and the lymphocyte‐monocyte ratio (LMR) could predict the prognosis of nasopharyngeal carcinoma (NPC). In this analysis, pretreatment GPS, NLR, PLR, LMR of 388 patients who were diagnosed as nonmetastatic NPC and recruited prospectively in the 863 Program No. 2006AA02Z4B4 were assessed. Of those, the 249 cases enrolled between December 27th 2006 and July 31st 2011 were defined as the development set. The rest 139 cases enrolled between August 1st 2011 and July 31st 2013 were defined as the validation set. The variables above were analyzed in the development set, together with age, gender, Karnofsky performance score, T stage, and N stage, with respect to their impact on the disease‐specific survival (DSS) through a univariate analysis. The candidate prognostic factors then underwent a multivariate analysis. A nomogram was established to predict the DSS, by involving the independent prognostic factors. Its predction capacity was evaluated through calculating Harrell's concordance index (C‐index) in the validation set. After multivariate analysis for the development set, age (≤50 vs. >50 years old), T stage (T1–2 vs. T3–4), N stage (N0–1 vs. N2–3) and pretreatment GPS (0 vs. 1–2), NLR (≤2.5 vs. >2.5), LMR (≤2.35 vs. >2.35) were independent prognostic factors of DSS (P values were 0.002, 0.008, <0.001, 0.004, 0.018, and 0.004, respectively). A nomogram was established by involving all the factors above. Its C‐index for predicting the DSS of the validation set was 0.734 (standard error 0.056). Pretreatment GPS, NLR, and LMR were independent prognostic factors of NPC. The nomogram based on them could be used to predict the DSS of NPC patients.

Combining plasma Epstein-Barr virus DNA and nodal maximal standard uptake values of 18F-fluoro-2-deoxy-D-glucose positron emission tomography improved prognostic stratification to predict distant metastasis for locoregionally advanced nasopharyngeal carcinoma

Background

This study aimed to evaluate the value of combining the nodal maximal standard uptake values (SUVmax) of ¹⁸ F-fluoro-2-deoxy-D-glucose positron emission tomography with Epstein-Barr virus DNA(EBV DNA) levels to predict distant metastasis for nasopharyngeal carcinoma (NPC) patients

Patients and Methods

Eight hundred seventy-four patients with stage III-IVa-b NPC were evaluated for the effects of combining SUVmax and EBV DNA levels on distant metastasis-free survival (DMFS), disease-free survival (DFS) and overall survival (OS).

Results

The optimal cutoff value was 6,220 copies/mL for EBV DNA and 7.5 for SUVmax-N. Patients with lower EBV DNA levels or SUVmax-N had a significantly better 3-year DMFS, DFS, and OS. Patients were divided into four groups based on EBV DNA and SUVmax-N, as follows: low EBV DNA and low SUVmax-N (LL), low EBV DNA and high SUVmax-N (LH), high EBV DNA and low SUVmax-N (HL), and high EBV DNA and high SUVmax-N (HH). There were significant differences between the four mentioned groups in 3-year DMFS: 95.7%, 92.2%, 92.3%, and 80.1%, respectively (P^trend < 0.001). When looking at the disease stage, the 3-year DMFS in group LL, LH, HL, HH were 94.2%, 92.9%, 95.0%, and 81.1%, respectively, in stage III patients (P^trend < 0.001) and 92.7%, 87.2%, 86.3%, and 77.0% in stage IVa–b patients (P^trend = 0.026).

Conclusion

Pretreatment EBV DNA and SUVmax of neck lymph nodes were independent prognostic factors for distant metastasis in NPC patients. Combining EBV DNA and SUVmax-N led to an improved risk stratification for distant metastasis in advanced-stage disease.

EBV-LMP1 suppresses the DNA damage response through DNA-PK/AMPK signaling to promote radioresistance in nasopharyngeal carcinoma

We conducted this research to explore the role of latent membrane protein 1 (LMP1) encoded by the Epstein-Barr virus (EBV) in modulating the DNA damage response (DDR) and its regulatory mechanisms in radioresistance. Our results revealed that LMP1 repressed the repair of DNA double strand breaks (DSBs) by inhibiting DNA-dependent protein kinase (DNA-PK) phosphorylation and activity. Moreover, LMP1 reduced the phosphorylation of AMP-activated protein kinase (AMPK) and changed its subcellular location after irradiation, which appeared to occur through a disruption of the physical interaction between AMPK and DNA-PK. The decrease in AMPK activity was associated with LMP1-mediated glycolysis and resistance to apoptosis induced by irradiation. The reactivation of AMPK significantly promoted radiosensitivity both in vivo and in vitro. The AMPKα (Thr172) reduction was associated with a poorer clinical outcome of radiation therapy in NPC patients. Our data revealed a new mechanism of LMP1-mediated radioresistance and provided a mechanistic rationale in support of the use of AMPK activators for facilitating NPC radiotherapy.

Chemotherapy for Nasopharyngeal Cancer: Neoadjuvant, Concomitant, and/or Adjuvant

Nasopharyngeal cancers are unique among other head and neck cancers, not only in epidemiology and histological characteristics, but also on treatment strategies as well. Radiotherapy is the primary treatment due to its radiosensitivity. In locally advanced stages, concurrent chemoradiation has been established to be effective to eradicate the disease and improve survival, in favor of radiotherapy alone. While increasing studies have explored the potential benefit of adding more chemotherapy to the concurrent regimen, whether adjuvant or neoadjuvant, it is generally agreed that proper patient selection is needed to stratify high-risk groups to intensify treatment and to optimize the disease outcome. Future studies are ongoing, possibly with the addition of biomarkers such as EBV DNA for risk group stratification. Refinement of patient groups that should be selected for combined modality treatment in stage II disease is also warranted.

A new prognostic histopathologic classification of nasopharyngeal carcinoma

Background

The current World Health Organization (WHO) classification of nasopharyngeal carcinoma (NPC) conveys little prognostic information. This study aimed to propose an NPC histopathologic classification that can potentially be used to predict prognosis and treatment response.

Methods

We initially developed a histopathologic classification based on the morphologic traits and cell differentiation of tumors of 2716 NPC patients who were identified at Sun Yat-sen University Cancer Center (SYSUCC) (training cohort). Then, the proposed classification was applied to 1702 patients (retrospective validation cohort) from hospitals outside SYSUCC and 1613 patients (prospective validation cohort) from SYSUCC. The efficacy of radiochemotherapy and radiotherapy modalities was compared between the proposed subtypes. We used Cox proportional hazards models to estimate hazard ratios (HRs) with 95% confidence intervals (CI) for overall survival (OS).

Results

The 5-year OS rates for all NPC patients who were diagnosed with epithelial carcinoma (EC; 3708 patients), mixed sarcomatoid-epithelial carcinoma (MSEC; 1247 patients), sarcomatoid carcinoma (SC; 823 patients), and squamous cell carcinoma (SCC; 253 patients) were 79.4%, 70.5%, 59.6%, and 42.6%, respectively (P < 0.001). In multivariate models, patients with MSEC had a shorter OS than patients with EC (HR = 1.44, 95% CI = 1.27–1.62), SC (HR = 2.00, 95% CI = 1.76–2.28), or SCC (HR = 4.23, 95% CI = 3.34–5.38). Radiochemotherapy significantly improved survival compared with radiotherapy alone for patients with EC (HR = 0.67, 95% CI = 0.56–0.80), MSEC (HR = 0.58, 95% CI = 0.49–0.75), and possibly for those with SCC (HR = 0.63; 95% CI = 0.40–0.98), but not for patients with SC (HR = 0.97, 95% CI = 0.74–1.28).

Conclusions

The proposed classification offers more information for the prediction of NPC prognosis compared with the WHO classification and might be a valuable tool to guide treatment decisions for subtypes that are associated with a poor prognosis.

Identification of a microRNA signature associated with risk of distant metastasis in nasopharyngeal carcinoma

Purpose

Despite significant improvement in locoregional control in the contemporary era of nasopharyngeal carcinoma (NPC) treatment, patients still suffer from a significant risk of distant metastasis (DM). Identifying those patients at risk of DM would aid in personalized treatment in the future. MicroRNAs (miRNAs) play many important roles in human cancers; hence, we proceeded to address the primary hypothesis that there is a miRNA expression signature capable of predicting DM for NPC patients.

Methods and results

The expression of 734 miRNAs was measured in 125 (Training) and 121 (Validation) clinically annotated NPC diagnostic biopsy samples. A 4-miRNA expression signature associated with risk of developing DM was identified by fitting a penalized Cox Proportion Hazard regression model to the Training data set (HR 8.25; p < 0.001), and subsequently validated in an independent Validation set (HR 3.2; p = 0.01). Pathway enrichment analysis indicated that the targets of miRNAs associated with DM appear to be converging on cell-cycle pathways.

Conclusions

This 4-miRNA signature adds to the prognostic value of the current “gold standard” of TNM staging. In-depth interrogation of these 4-miRNAs will provide important biological insights that could facilitate the discovery and development of novel molecularly targeted therapies to improve outcome for future NPC patients.

Prognostic Indications of Elevated MCT4 and CD147 across Cancer Types: A Meta-Analysis

Background. Metabolism in the tumor microenvironment can play a critical role in tumorigenesis and tumor aggression. Metabolic coupling may occur between tumor compartments; this phenomenon can be prognostically significant and may be conserved across tumor types. Monocarboxylate transporters (MCTs) play an integral role in cellular metabolism via lactate transport and have been implicated in metabolic synergy in tumors. The transporters MCT1 and MCT4 are regulated via expression of their chaperone, CD147. Methods. We conducted a meta-analysis of existing publications on the relationship between MCT1, MCT4, and CD147 expression and overall survival and disease-free survival in cancer, using hazard ratios derived via multivariate Cox regression analyses. Results. Increased MCT4 expressions in the tumor microenvironment, cancer cells, or stromal cells were all associated with decreased overall survival and decreased disease-free survival (p < 0.001 for all analyses). Increased CD147 expression in cancer cells was associated with decreased overall survival and disease-free survival (p < 0.0001 for both analyses). Few studies were available on MCT1 expression; MCT1 expression was not clearly associated with overall or disease-free survival. Conclusion. MCT4 and CD147 expression correlate with worse prognosis across many cancer types. These results warrant further investigation of these associations.

Management of Nasopharyngeal Carcinoma: Current Practice and Future Perspective

Nasopharyngeal carcinoma of the undifferentiated subtype is endemic to southern China, and patient prognosis has improved significantly over the past three decades because of advances in disease management, diagnostic imaging, radiotherapy technology, and broader application of systemic therapy. Despite the excellent local control with modern radiotherapy, distant failure remains a key challenge. Advances in molecular technology have helped to decipher the molecular pathogenesis of nasopharyngeal carcinoma as well as its etiologic association with the Epstein-Barr virus. This in turn has led to the discovery of novel biomarkers and drug targets, rendering this cancer site a current focus for new drug development. This article reviews and appraises the key literature on the current management of nasopharyngeal carcinoma and future directions in clinical research.

Pretreatment hematologic markers as prognostic factors in patients with nasopharyngeal carcinoma: Neutrophil-lymphocyte ratio and platelet-lymphocyte ratio

BACKGROUND

Pretreatment hematological markers of inflammatory response have emerged as prognostic factors for patients with cancer. In this study, we evaluated the prognostic significance of various hematologic parameters in patients with nasopharyngeal carcinoma (NPC).

METHODS

Clinical data from 251 patients with NPC were retrospectively collected. Neutrophil counts, lymphocyte counts, platelet counts, neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR) were adopted as potential prognostic biomarkers. The Kaplan-Meier method and log-rank test were adopted to calculate and compare the progression-free survival (PFS) and overall survival (OS) rates. The Cox proportional hazards model was used to carry out univariate and multivariate analyses.

RESULTS

NLR ≥2.7 (hazard ratio [HR] = 2.01; 95% confidence interval [CI] = 1.23-3.29; p = .005) and PLR ≥167.2 (HR = 2.12; 95% CI = 1.35-3.33; p = .001) were significantly associated with shorter PFS, whereas PLR ≥163.4 (HR = 2.64; 95% CI = 1.25-5.60; p = .011) was correlated with poor OS.

CONCLUSION

Pretreatment NLR and PLR can be independent prognostic factors for patients with NPC. © 2015 Wiley Periodicals, Head Neck 38: E1332-E1340, 2016.

Minimum absolute lymphocyte count during radiotherapy as a new prognostic factor for nasopharyngeal cancer

BACKGROUND

The purpose of this study was to investigate whether the minimum absolute lymphocyte count (ALC) during radiotherapy (RT) could predict clinical outcome in patients with nasopharyngeal cancer (NPC).

METHODS

We analyzed 70 patients with NPC including 63 patients treated with chemoradiotherapy and used multivariate analysis to determine whether minimum ALC affected clinical outcome.

RESULTS

Patients were grouped by minimum ALC, with a cutoff of 245 cells/μL. Five-year disease-specific survival (DSS) and progression-free survival (PFS) for patients with minimum ALC ≥245 versus minimum ALC <245 were 88.1% versus 60.8% (p = .004) and 71.2% versus 35.2% (p = .004). All 10 patients with minimum ALC <120 experienced disease progression. Four of 6 patients (67%) with ALC <120 who died experienced disease progression within 6 months.

CONCLUSION

Minimum ALC may predict poor 5-year DSS and should be evaluated by prospective studies. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1061-E1067, 2016.

Cancer Prevention Research in China

Although cancer incidence and mortality rates in the United States and some European countries have started to decrease, those in developing countries are increasing. China, the most populous developing country, is facing a serious challenge from cancer. Cancer incidence has been increasing for decades, and cancer is the leading cause of death in China. In 2012, the cancer incidence was 174.0 per 100,000, and the cancer mortality was 122.2 per 100,000 in China. In addition to the still-prevalent traditional Chinese cancers of the stomach, liver, esophagus, cervix, and nasopharynx, the incidence of "Western" cancers such those of the lung, breast, and colorectum has increased alarmingly in recent years. These increases are likely due to the lifestyle and environmental changes associated with rapid economic development and population aging. More importantly, a large portion of these cancers are preventable. Researchers in China have made important contributions to cancer prevention research, especially in the traditional Chinese cancers. More cancer prevention research and measures, especially on the major emerging cancers, are urgently needed. This review article highlights some of the past achievements and present needs in cancer prevention research in China and suggests important areas for future studies.

miR-29a/b enhances cell migration and invasion in nasopharyngeal carcinoma progression by regulating SPARC and COL3A1 gene expression

Nasopharyngeal carcinoma (NPC) is a malignant tumor associated with a genetic predisposition, Epstein-Barr virus infection and chromosomal abnormalities. Recently, several miRNAs have been shown to target specific mRNAs to regulate NPC development and progression. However, the involvement of miRNAs in processes leading to NPC migration and invasion remains to be elucidated. We predicted that miR-29a/b are associated with dysregulated genes controlling NPC through an integrated interaction network of miRNAs and genes. miR-29a/b over-expression in NPC cell lines had no significant effect on proliferation, whereas miR-29b mildly increased the percentage of cells in the G1 phase with a concomitant decrease in the percentage of cells in S phase. Furthermore, we demonstrated that miR-29a/b might be responsible for increasing S18 cell migration and invasion, and only COL3A1 was identified as a direct target of miR-29b despite the fact that both SPARC and COL3A1 were inhibited by miR-29a/b over-expression. Meanwhile, SPARC proteins were increased in metastatic NPC tissue and are involved in NPC progression. Unexpectedly, we identified that miRNA-29b expression was elevated in the serum of NPC patients with a high risk of metastasis. The 5-year actuarial overall survival rates in NPC patients with high serum miR-29b expression was significantly shorter than those with low serum miR-29b expression; therefore, serum miR-29b expression could be a promising prognostic marker.

Pretreatment platelet count improves the prognostic performance of the TNM staging system and aids in planning therapeutic regimens for nasopharyngeal carcinoma: a single-institutional study of 2,626 patients

INTRODUCTION

Thrombocytosis has been identified as an unfavorable prognostic factor in several types of cancer. This study aimed to evaluate the prognostic value of pretreatment platelet count in association with the TNM staging system and therapeutic regimens in patients with nasopharyngeal carcinoma (NPC).

METHODS

A total of 2,626 patients with NPC were retrospectively analyzed. Platelet count >300 × 10(9)/L was defined as thrombocytosis. Matched-pair analysis was performed between patients receiving chemoradiotherapy and radiotherapy.

RESULTS

Multivariate analysis showed that platelet count was an independent unfavorable prognostic factor for overall survival (OS) [hazard ratio (HR) = 1.810, 95% confidence interval (CI) = 1.531-2.140, P < 0.001] and distant metastasis-free survival (DMFS) (HR = 1.873, 95% CI = 1.475-2.379, P < 0.001) in the entire patient cohort. Further subgroup analysis revealed that increased platelet count was an independent unfavorable prognostic factor for OS and DMFS in patients with NPC stratified by early and advanced T category, N category, or TNM classification (all P ≤ 0.001). Receiver operating characteristic (ROC) curves verified that the predictive value of TNM classification for OS was improved when combined with pretreatment platelet count (P = 0.030). Matched-pair analysis showed that chemoradiotherapy significantly improved OS only in advanced-stage NPC with thrombocytosis (HR = 0.416, 95% CI = 0.226-0.765, P = 0.005).

CONCLUSIONS

Pretreatment platelet count, when combined with TNM classification, is a useful indicator for metastasis and survival in patients with NPC. It may improve the predictive value of the TNM classification and help to identify patients likely to benefit from more aggressive therapeutic regimens.

Ribonucleotide reductase M2 subunit expression and prognostic value in nasopharyngeal carcinoma

The ribonucleotide reductase M2 subunit (RRM2) modulates the enzymatic activity of ribonucleotide reductase, and is involved in tumor progression. Recently, high levels of RRM2 expression were reported to correlate with poor survival outcomes in patients with colorectal and bladder cancer. However, changes in RRM2 expression in nasopharyngeal carcinoma (NPC), and its effect on the prognosis of this disease remain unknown. The aim of the present study was to analyze the expression of RRM2 in NPC cell lines, and to identify whether RRM2 may serve as a biomarker with which to assess the prognosis of NPC. The present study found that RRM2 expression was higher in NPC cell lines and tissue samples than in noncancerous nasopharyngeal epithelial cell lines and noncancerous tissues, as shown by reverse transcription-quantitative polymerase chain reaction analysis, western blotting and immunohistochemistry staining. Kaplan-Meier survival analysis demonstrated that patients with higher RRM2 expression levels had poorer disease-free survival outcomes than those with lower expression levels of RRM2. Univariate analysis showed that a lower survival rate was significantly associated with high RRM2 expression levels [hazard ratio (HR), 6.424; 95% confidence interval (CI), 2.381-17.333; P<0.001]. Multivariate analysis indicated that RRM2 expression is an independent prognostic factor for patients with NPC (HR, 3.461; 95 % CI, 1.204-9.949; P=0.021). Overexpression of RRM2 led to increased cell proliferation, colony formation, migration and invasion in vivo. These results suggest that high levels of RRM2 expression may be a useful predictor for survival in patients with NPC and may serve as a novel prognostic indicator for these individuals.

Molecular markers to assess short-term disease local recurrence in nasopharyngeal carcinoma

An important challenge in nasopharyngeal carcinoma (NPC) research is to develop effective predictors of tumor recurrence following treatment to determine whether immediate adjuvant therapy is necessary. We retrospectively analyzed archived specimens collected from 45 patients with paired samples of primary NPC (pNPC) and recurrent NPC (rNPC). Clinical samples were collected from the Cancer Center Databases of the First People’s Hospital of Foshan and Shantou Central Hospital (affiliates of Sun Yat-Sen University) between 2001 and 2012. Expression levels of phosphor-Stat3 (p-Stat3), signalosome complex subunit 5 (Jab1/Csn5), Akt1, C/EBP homologous protein (CHOP), Ki-67, and apoptosis were determined by immunohistochemistry in pNPC and rNPC samples from the same patients. Differences in these markers between the short-term interval to recurrence (ITR) group (ITR <18 months) and long-term ITR group (ITR ≥18 months) were further analyzed. In Cox’s regression analysis, the ITR was significantly associated as an independent-negative prognostic factor for overall survival (hazard ratio, 0.211; 95% confidence interval, 0.053–0.841; P=0.027). p-Stat3 was increased in the short-term ITR group (ITR <18 months) and tended to be lower in the long-term ITR group (ITR ≥18 months). In the short-term ITR group, nuclear Akt expression was significantly increased in paired rNPC (P=0.028). In the long-term ITR group, the expression of nuclear Jab1/Csn5 (P=0.047) and assessment of apoptosis measured with TdT-mediated dUTP nick end-labeling (TUNEL) (P=0.003) was significantly increased in paired rNPC. The results suggest that differences between short- and long-term ITR may predict outcome in rNPC. Furthermore, the overexpression of Jab1/Csn5 and Akt may contribute to the carcinogenesis of rNPC, and Akt seems to promote the progression of short-term ITR. Intra-individual changes of Jab1/Csn5, Akt, and TUNEL may help to identify short-term ITR.

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.

Elevated levels of plasma D-dimer predict a worse outcome in patients with nasopharyngeal carcinoma

BACKGROUND

Hemostatic alterations occur during the development of cancer. Plasma D-dimer is a hypercoagulability and fibrinolytic system marker that is increased in patients with various solid tumours. The aim of this study was to evaluate the hemostatic status of nasopharyngeal carcinoma (NPC) patients by assessing plasma D-dimer levels to investigate its value as a prognostic marker.

METHODS

We retrospectively analysed 717 patients with nasopharyngeal carcinoma, and we applied Cox regression and log-rank tests to assess the association of D-dimer levels with disease-free survival (DFS), distant metastasis-free survival (DMFS), and overall survival (OS). D-dimer levels were measured using a quantitative D-dimer latex agglutination assay.

RESULTS

Using the 3rd quartile values (0.8 μg/L) as the optimal cut-offs, we found that patients with high D-dimer levels have a shorter 3-year DFS, (79%, 95%CI (73.1-84.9)) vs. (69%, 95%CI (59.2-78.8)), DMFS (87%, 95%CI (83.1-90.9)) vs. (77%, 95%CI (69.2-84.8)), and overall survival (82%, 95%CI (76.1-87.9)) vs. (76%, 95%CI (66.2-85.8)). Multivariate analysis revealed that pre-treatment D-dimer levels and EBV DNA were significant independent factors for DFS, DMFS, and OS in NPC patients. Subgroup analyses indicated that the plasma D-dimer levels could effectively stratify patient prognosis for early cancer, advanced stage cancer, and patients with EBV DNA ≥4000 copies/ml.

CONCLUSIONS

High D-dimer levels were associated with poor disease-free survival, distant metastasis-free survival, overall survival, and increased risk of mortality in NPC patients. Prospective trials are required to assess the prognostic value of D-dimer levels.

The impact of plasma Epstein-Barr virus DNA and fibrinogen on nasopharyngeal carcinoma prognosis: an observational study

BACKGROUND

The impact of combining plasma fibrinogen levels with Epstein-Barr Virus DNA (EBV DNA) levels on the prognosis for patients with nasopharyngeal carcinoma (NPC) was evaluated.

METHODS

In this observational study, 2563 patients with non-metastatic NPC were evaluated for the effects of circulating plasma fibrinogen and EBV DNA levels on disease-free survival (DFS), distant metastasis-free survival (DMFS), and overall survival (OS).

RESULTS

Compared with the bottom biomarker tertiles, TNM stage-adjusted hazard ratios (HR, 95% confidence intervals (CIs)) for predicting DFS in fibrinogen tertiles 2 to 3 were 1.26 (1.00 to 1.60) and 1.81 (1.45 to 2.26), respectively; HR for EBV DNA tertiles 2 to 3 were 1.49 (1.12 to 1.98) and 4.24 (3.27 to 5.49), respectively. After additional adjustment for established risk factors, both biomarkers were still associated (P for trend <0.001) with reduced DFS (HR: 1.79, 95% CI, 1.43 to 2.25 for top fibrinogen tertiles; HR: 4.04, 95% CI: 3.10 to 5.27 for top EBV DNA tertiles compared with the bottom tertiles). For patients with advanced-stage disease, those with high fibrinogen levels (3.34 g l(-1)) presented with worse DFS, regardless of EBV DNA 4000 or <4000 copies ml(-1) subgroup. Similar findings were observed for DMFS and OS.

CONCLUSIONS

Circulating fibrinogen and EBV DNA significantly correlate with NPC patients survival. Combined fibrinogen and EBV DNA data lead to improved prognostic prediction in advanced-stage disease.

CLIC4, ERp29, and Smac/DIABLO derived from metastatic cancer stem-like cells stratify prognostic risks of colorectal cancer

PURPOSE

Cancer stem-like cells have been well accepted to be involved in recurrence and metastasis of cancers, but the prognostic potential of biomarkers integrating with metastasis and cancer stem-like cells for colorectal cancer is unclear.

EXPERIMENTAL DESIGN

We identified three proteins, CLIC4, ERp29, and Smac/DIABLO, from metastatic cancer stem-like cells of colorectal cancer and verified the proteins' role in metastatic behaviors. The proteins were detected by IHC in colorectal cancer tumors and matched colonic mucosa from patients with colorectal cancer who underwent radical surgery in the training cohort. The associations between proteins expression levels and five-year disease-specific survival (DSS) were evaluated to predict the survival probability in the training cohort of 421 cases and the validation cohort of 228 cases.

RESULTS

A three-protein panel including CLIC4, ERp29, and Smac/DIABLO, which was generated from multivariate analysis by excluding clinicopathologic characteristics from the training cohort, distinguished patients with colorectal cancer into very low-, low-, middle-, and high-risk groups with significant differences in five-year DSS probability (88.6%, 63.3%, 30.4%, 11.4%; P < 0.001). The panel is independent from tumor-node-metastasis staging system and histologic grading to predict prognosis, and also enables classification of validation cohort into four risk stratifications (five-year DSS probability is 98.2%, 80.2%, 25.6%, and 2.7%; P < 0.001).

CONCLUSIONS

CLIC4, ERp29, and Smac/DIABLO integrated into a novel panel based on cancer stem-like cells in association with metastasis stratify the prognostic risks of colorectal cancer. Prediction of risks with molecular markers will benefit clinicians to make decisions of individual management with postoperative colorectal cancer patients.

MR imaging prediction of local control of nasopharyngeal carcinoma treated with radiation therapy and chemotherapy

OBJECTIVE

To retrospectively evaluate the association of MRI findings with local control of nasopharyngeal carcinoma (NPC) treated with radiation therapy and chemotherapy (chemoradiotherapy).

METHODS

Pre-treatment MRIs of 101 patients (78 males and 23 females, 23-79 years of age) who had NPC treated with chemoradiotherapy were retrospectively reviewed to evaluate tumour involvement of nasopharyngeal anatomic subsites, tumour volume and MRI appearance. Local control rates were evaluated with respect to these MRI findings.

RESULTS

Univariate analysis (using the Kaplan-Meier method) showed that invasion of the skull base as determined by MRI was a significant predictor of local control. In terms of clinical characteristics, T stage and pathological subtype were significant predictors of local control. Multivariate analysis (Cox regression model) of the radiologic findings and clinical characteristics revealed that invasion of the skull base (p = 0.003) and pathological subtype (p < 0.001) were independent prognostic factors for local control.

CONCLUSION

Invasion of the skull base as determined by MRI predicts the likelihood of local failure and may be helpful in identifying a subset of patients with tumours at risk of local recurrence within 3 years after primary chemoradiotherapy.

ADVANCES IN KNOWLEDGE

It has now become common practice to use MRI for pre-treatment evaluation of patients with NPC. The potential role for MRI findings in predicting local control and prognosis in patients with NPC has implications for treatment planning.

MicroRNA-30a promotes invasiveness and metastasis in vitro and in vivo through epithelial-mesenchymal transition and results in poor survival of nasopharyngeal carcinoma patients

Although microRNA-30a (miR-30a) has been shown to regulate cancer metastasis, the molecular mechanism has not yet been clearly elucidated in nasopharyngeal carcinoma (NPC). The present study was to investigate the miR-30a expression pattern and its potential functions and further to identify its target gene and corresponding clinical applications in NPC. MiR-30a was identified to be down-regulated in NPC primary tumors compared with metastatic tumors using quantitative real-time PCR. Furthermore, over-expression of miR-30a transfected with precursor increased the ability of metastasis and invasion of NPC tumor cells in vivo and in vitro. E-cadherin was screened as a putative target gene of miR-30a by computational algorithms. Luciferase reporter assays showed that over-expression of miR-30a directly reduced the activity of a luciferase transcript combined with the 3'-untranslated region (3'-UTR) of E-cadherin. Kaplan-Meier survival analysis and log-rank test were analyzed for 1077 NPC patients for overall survival, indicating that a high expression of E-cadherin was beneficial for NPC prognosis (P = 0.001). Importantly, NPC patients with high expression of E-cadherin had much lower risk of poor prognosis (hazard ratio = 0.757, P = 0.017) using multivariate analysis. In conclusion, miR-30a could play an important role in regulating NPC metastasis and potentially provide useful guidelines for individualized therapy.

Profiling Plasma MicroRNA in Nasopharyngeal Carcinoma with Deep Sequencing

BACKGROUND

The goal of this study was to establish a plasma microRNA profile by use of next-generation sequencing that could aid in assessment of patient prognosis in nasopharyngeal carcinoma (NPC).

METHODS

Two panels of NPC patients and healthy controls (HCs) were recruited for this study. We used deep sequencing to screen plasma microRNAs. Differentially expressed microRNAs were verified by quantitative real-time PCR (qPCR). Kaplan–Meier survival analysis with the log-rank test was used to compare overall survival (OS) and progression-free survival (PFS) between groups.

RESULTS

Twenty-three plasma miRNAs with differential expression levels were selected for qPCR analysis on an independent set including 100 NPC patients and 55 HCs. NPC patients with low concentrations of miR-483–5p and miR-103 had better prognosis for 5-year OS than those with high concentrations (87.5% vs 55.8%, P &lt; 0.001; 80.9% vs 62.3%, P = 0.031). Those with low concentrations of miR-29a and let-7c had poorer prognosis (54.8% vs 82.8%, P = 0.002; 56.3% vs 84.6%, P = 0.001). A 3-signature miRNA integrated with clinical stage was further identified in an independent set. We calculated a prognostic index score and classified patients into low-, medium-, and high-risk groups. Five-year OS among the 3 groups was significantly different (90.9%, 66.7%, and 23.8%; P &lt; 0.001). By multivariate analysis, a high-risk score was the most significantly unfavorable prognostic factor independent of other clinical variables (P &lt; 0.001, hazard ratio = 15.1, 95% CI = 5.2–43.9).

CONCLUSIONS

Differentially expressed plasma miRNAs as identified by next-generation sequencing can be helpful for predicting survival in NPC patients.

Knockdown of miR-214 promotes apoptosis and inhibits cell proliferation in nasopharyngeal carcinoma

MicroRNA-214 (MiR-214) is aberrantly expressed in several human tumors such as ovarian cancer and breast cancer. However, the role of miR-214 in nasopharyngeal carcinoma (NPC) is still unknown. In this study, we report that miR-214 was overexpressed in NPC cell lines and tissues. Silencing of miR-214 by LNA-antimiR-214 in NPC cells resulted in promoting apoptosis and suppressing cell proliferation in vitro, and suppressed tumor growth in nude mice in vivo. Luciferase reporter assay was performed to identify Bim as a direct target of miR-214. Furthermore, this study showed that low Bim expression in NPC tissues correlated with poor survival of NPC patients. Taken together, our findings suggest that miR-214 plays an important role in NPC carcinogenesis.

Epstein-Barr virus induction of the Hedgehog signalling pathway imposes a stem cell phenotype on human epithelial cells

Nasopharyngeal carcinoma (NPC) is a cancer common in southern China and South East Asia that is causally linked to Epstein-Barr virus (EBV) infection. Here, we demonstrate that NPC displays frequent dysregulation of the Hedgehog (HH) pathway, a pathway implicated in the maintenance of stem cells, but whose aberrant activation in adult tissues can lead to cancer. Using authentic EBV-positive carcinoma-derived cell lines and nasopharyngeal epithelial cell lines latently infected with EBV as models for NPC in vitro, we show that EBV activates the HH signalling pathway through autocrine induction of SHH ligand. Moreover, we find that constitutive engagement of the HH pathway induces the expression of a number of stemness-associated genes and imposes stem-like characteristics on EBV-infected epithelial cells in vitro. Using epithelial cells expressing individual EBV latent genes detected in NPC, we show that EBNA1, LMP1, and LMP2A are all capable of inducing SHH ligand and activating the HH pathway, but only LMP1 and LMP2A are able to induce expression of stemness-associated marker genes. Our findings not only identify a role for dysregulated HH signalling in NPC oncogenesis, but also provide a novel rationale for therapeutic intervention.

Prognostic role of epidermal growth factor receptor in nasopharyngeal carcinoma: a meta-analysis

BACKGROUND

Various studies have assessed the prognostic value of epidermal growth factor receptor (EGFR) overexpression in nasopharyngeal carcinoma (NPC), but their results remain controversial.

METHODS

Studies published up to January 2013 were collected. A total of 16 studies involving 1179 patients were reviewed. A meta-analysis was performed to clarify the prognostic role of EGFR in patients with NPC. The combined hazard ratio (HR) and 95% confidence interval (CI) were estimated using fixed-effects or random-effects models.

RESULTS

EGFR overexpression had significantly poor effect on overall survival (OS; HR, 1.86; 95% CI, 1.25-2.77), disease-free survival (DFS; HR, 2.25; 95% CI, 1.66-3.04) and locoregional control (HR, 2.93; 95% CI, 1.71-5.02). However, the association between EGFR overexpression and distant metastasis-free survival was not statistically significant (HR, 1.39; 95% CI, 0.72-2.67).

CONCLUSION

EGFR overexpression can be a prognostic factor for patients with NPC.

Cancer stem-like cell characteristics induced by EB virus-encoded LMP1 contribute to radioresistance in nasopharyngeal carcinoma by suppressing the p53-mediated apoptosis pathway

Emerging evidence confirms that cancer stem cells (CSCs) are responsible for the chemoradioresistance of malignancies. EBV-encoded latent membrane protein 1 (LMP1) is associated with tumor relapse and poor prognosis of nasopharyngeal carcinoma (NPC). However, whether LMP1 induces the development of CSCs and the mechanism by which this rare cell subpopulation leads to radioresistance in NPC remain unclear. In the present study, LMP1-transformed NPC cells showed significant radioresistance compared to the empty vector control. We found that LMP1 up-regulated the expression of several stemness-related genes, increased the cell number of side population (SP) by flow cytometry analysis, enhanced the self-renewal properties of the cells in a spherical culture and enhanced the in vivo tumor initiation ability. We also found that LMP1 positively regulated the expression of the CSC marker CD44. The CD44(+/High) subpopulation of the LMP1-transformed NPC cells displayed more significant CSC characteristics than the CD44(-/Low) subpopulation of the LMP1-transformed NPC cells; these characteristics included the upregulation of stemness-related genes, in vitro self-renewal and in vivo tumor initiation ability. Importantly, the CD44(+/High) subpopulation displayed more radioresistance than the CD44(-/Low) subpopulation. Our results also demonstrated that phosphorylation of the DNA damage response (DDR) proteins, ATM, Chk1, Chk2 and p53, was inactivated in the LMP1-induced CD44(+/High) cells in response to DNA damage, and this was accompanied by a downregulation of the p53-targeted proapoptotic genes, which suggested that the inactivation of the p53-mediated apoptosis pathway was responsible for the radioresistance in the CD44(+/High) cells. Taken together, we found that LMP1 induced an increase in CSC-like CD44(+/High) cells, and we determined the molecular mechanism underlying the radioresistance of the LMP1-activated CSCs, highlighting the need of CSC-targeted radiotherapy in EBV-positive NPC.

Epstein-Barr Virus_Encoded LMP1 upregulates microRNA-21 to promote the resistance of nasopharyngeal carcinoma cells to cisplatin-induced Apoptosis by suppressing PDCD4 and Fas-L

Approximately 30% of patients with Epstein-Barr virus (EBV)-positive advanced nasopharyngeal carcinoma (NPC) display chemoresistance to cisplatin-based regimens, but the underlying mechanisms are unclear. The Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1), a functional homologue of the tumor necrosis factor receptor family, contributes substantially to the oncogenic potential of EBV through the activation of multiple signaling pathways, and it is closely associated with a poorer prognosis for NPC. Recent studies show that EBV infection can induce the expression of many cellular miRNAs, including microRNA-21, a biomarker for chemoresistance. However, neither a link between LMP1 expression and miR-21 upregulation nor their cross talk in affecting chemoresistance to cisplatin have been reported. Here, we observed that stable LMP1-transformed NPC cells were less sensitive to cisplatin treatment based on their proliferation, colony formation, the IC₅₀ value of cisplatin and the apoptosis index. Higher levels of miR-21 were found in EBV-carrying and LMP1-positive cell lines, suggesting that LMP1 may be linked to miR-21 upregulation. These data were confirmed by our results that exogenous LMP1 increased miR-21 in both transiently and stably LMP1-transfected cells, and the knock down of miR-21 substantially reversed the resistance of the NPC cells to cisplatin treatment. Moreover, the proapoptotic factors programmed cell death 4 (PDCD4) and Fas ligand (Fas-L), which were negatively regulated by miR-21, were found to play an important role in the program of LMP1-dependent cisplatin resistance. Finally, we demonstrated that LMP1 induced miR-21 expression primarily by modulating the PI3K/AKT/FOXO3a signaling pathway. Taken together, we revealed for the first time that viral LMP1 triggers the PI3K/Akt/FOXO3a pathway to induce human miR-21 expression, which subsequently decreases the expression of PDCD4 and Fas-L, and results in chemoresistance in NPC cells.

Functional polymorphisms of matrix metalloproteinase-9 and survival in patients with locoregionally advanced nasopharyngeal carcinoma treated with chemoradiotherapy

To investigate the prognostic role of major matrix metalloproteinase (MMP) gene polymorphisms in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) treated with chemoradiotherapy. Four hundred twenty-one consecutive NPC patients were prospectively recruited. Two hundred patients were randomly selected as the training cohort, and the remaining 221 patients were the validation cohort. Twelve polymorphisms in the MMP-1, 2, 3, 7, 8, and 9 genes were genotyped by ligase detection reaction-PCR. MMP-9 rs2250889 PR/RR (HR = 2.287, 95% CI 1.400-3.735) and rs17576 RQ/QQ (HR = 2.347, 95% CI 1.431-3.849) genotypes were significantly related with increased death risk in the training cohort. Analysis of the validation cohort confirmed these results (rs2250889: HR = 2.231, 95% CI 1.281-3.886; rs17576: HR = 2.987, 95% CI 1.674-5.330). Multivariate analysis showed that rs17576 (HR = 2.284, 95% CI 1.123-4.643, P = 0.023) was still an independent prognostic factor. The MMP-9 rs17576 is a novel independent prognostic marker in patients with locoregionally advanced NPC treated with chemoradiotherapy.

Staging of nasopharyngeal carcinoma--the past, the present and the future

This article reviews the evolution of the International Union Against Cancer/American Joint Committee on Cancer staging system for nasopharyngeal carcinoma. With the increasing availability of newer imaging methods, more sophisticated radiotherapy techniques and rapidly evolving molecular assays, we also examine newer clinical features that might have impact on staging. A new version of the staging system taking into account of some of these factors is also proposed.

Protein tyrosine kinase 6 is associated with nasopharyngeal carcinoma poor prognosis and metastasis

Background

The aim of this study was to analyze the expression of protein tyrosine kinase 6 (PTK6) in nasopharyngeal carcinoma (NPC) samples, and to identify whether PTK6 can serve as a biomarker for the diagnosis and prognosis of NPC.

Methods

We used quantitative RT-PCR and Western blotting analysis to detect mRNA and protein expression of PTK6 in NPC cell lines and immortalized nasopharyngeal epithelial cell lines. 31 NPC and 16 non-tumorous nasopharyngeal mucosa biopsies were collected to detect the difference in the expression of mRNA level of PTK6 by quantitative RT-PCR. We also collected 178 NPC and 10 normal nasopharyngeal epithelial cases with clinical follow-up data to investigate the expression of PTK6 by immunohistochemistry staining (IHC). PTK6 overexpression on cell growth and colony formation ability were measured by the method of cell proliferation assay and colony formation assay.

Results

The expression of PTK6 was higher in most of NPC cell lines at both mRNA and protein levels than in immortalized nasopharyngeal epithelial cell lines (NPECs) induced by Bmi-1 (Bmi-1/NPEC1, and Bmi-1/NPEC2). The mRNA level of PTK6 was high in NPC biopsies compared to non-tumorous nasopharyngeal mucosa biopsies. IHC results showed the expression of PTK6 was significantly correlated to tumor size (P<0.001), clinical stage (P<0.001), and metastasis (P=0.016). The patients with high-expression of PTK6 had a significantly poor prognosis compared to those of low-expression (47.8% versus 80.0%, P<0.001), especially in the patients at the advanced stages (42.2% versus 79.1%, P<0.001). Multivariate analysis indicated that the level of PTK6 expression was an independent prognostic factor for the overall survival of patients with NPC (P <0.001). Overexpression of PTK6 in HNE1 cells enhanced the ability of cell proliferation and colony formation.

Conclusions

Our results suggest that high-expression of PTK6 is an independent factor for NPC patients and it might serve as a potential prognostic biomarker for patients with NPC.