Su Mei Cao

Fluctuations of Epstein-Barr Virus Serological Antibodies and Risk for Nasopharyngeal Carcinoma: A Prospective Screening Study with a 20-Year Follow-Up

Background The impact of variation of Epstein-Barr virus (EBV) antibody titers before the development of nasopharyngeal carcinoma (NPC) is still unclear. We analyzed the fluctuations of antibodies against EBV before histopathological diagnosis to assess the risk of NPC and aimed to provide a reliable basis for screening in high risk populations. Methods This study was based on a population-based screening program in Sihui County in Guangdong Province of China. A total of 18,986 subjects were recruited in 1987 and 1992, respectively. Baseline and repeated serological tests were performed for IgA antibodies against EBV capsid antigen (VCA/IgA) and early antigen (EA/IgA). Follow-up until the end of 2007 was accomplished through linkage with population and health registers. Cox proportional hazards regression model was used to estimate the relative risk of NPC in association with EBV antibodies. Time-dependent receiver operating characteristic curve (ROC) analysis was used to further evaluate the predictive ability. Results A total of 125 NPCs occurred during an average of 16.9 years of follow-up. Using baseline information alone or together with repeated measurements, serological levels of VCA/IgA and EA/IgA were significantly associated with increased risks for NPC, with a striking dose-response relationship and most prominent during the first 5 years of follow-up. Considering the fluctuant types of serological titers observed during the first three tests, relative risk was highest among participants with ascending titers of EBV VCA/IgA antibodies with an adjusted hazard ratio (HR) of 21.3 (95% confidence interval [CI] 7.1 to 64.1), and lowest for those with decreasing titers (HR = 1.5, 95% CI 0.2 to 11.4), during the first 5 years of follow-up. Time-dependent ROC analysis showed that VCA/IgA had better predictive performance for NPC incidence than EA/IgA. Conclusion Our study documents that elevated EBV antibodies, particularly with ascending titers, are strongly associated with an increased risk for NPC.

Centromere Protein H Is a Novel Prognostic Marker for Nasopharyngeal Carcinoma Progression and Overall Patient Survival

Purpose: The aim of the present study was to analyze the expression of Centromere protein H (CENP-H), one of the fundamental components of the human active kinetochore, in nasopharyngeal carcinoma (NPC) and to correlate it with clinicopathologic data, including patient survival. Experimental Design: Using reverse transcription-PCR and Western blot, we detected the expression of CENP-H in normal nasopharyngeal epithelial cells, immortalized nasopharyngeal epithelial cell lines, and NPC cell lines. Using immunohistochemistry, we analyzed CENP-H protein expression in 160 clinicopathologically characterized NPC cases. Statistical analyses were applied to test for prognostic and diagnostic associations. Results: Reverse transcription-PCR and Western blot showed that the expression level of CENP-H was higher in NPC cell lines and in immortalized nasopharyngeal epithelial cells than in the normal nasopharyngeal epithelial cell line at both transcriptional and translational levels. By immunohistochemical analysis, we found that 76 of 160 (47.5%) paraffin-embedded archival NPC biopsies showed high expression of CENP-H. Statistical analysis showed that there was a significant difference of CENP-H expression in patients categorized according to clinical stage (P = 0.024) and T classification (P = 0.027). Patients with higher CENP-H expression had shorter overall survival time, whereas patients with lower CENP-H expression had better survival. A prognostic value of CENP-H was also found of the subgroup of N0-N1 tumor classification. Multivariate analysis showed that CENP-H expression was an independent prognostic indicator for patients survival. Conclusions: Our results suggest that CENP-H protein is a valuable marker of NPC progression. High CENP-H expression is associated with poor overall survival in NPC patients.

Two Epstein-Barr Virus–Related Serologic Antibody Tests in Nasopharyngeal Carcinoma Screening: Results From the Initial Phase of a Cluster Randomized Controlled Trial in Southern China

A nasopharyngeal carcinoma (NPC) mass screening trial using a combination of immunoglobulin A antibodies to Epstein-Barr virus capsid antigen and nuclear antigen-1 by enzyme-linked immunosorbent assay in addition to indirect mirror examination in the nasopharynx and/or lymphatic palpation (IMLP) was conducted in southern China. Cantonese aged 30-59 years residing in 2 cities randomly selected by cluster sampling, Sihui and Zhongshan, were invited to participate in this screening from May 2008 through May 2010. Participants were offered fiberoptic endoscopy examination and/or pathologic biopsy if their serologic tests reached our predefined level of high risk or if results from the physical examination indicated possible cancer (i.e., were IMLP positive). A total of 28,688 individuals were voluntarily screened in the initial round. The overall NPC detection rate was 0.14% (41/28,688) with an early diagnosis rate of 68.3% (28/41) during the first year of follow-up. Thirty-eight of 41 cases (92.7%) were detected among the high-risk group, and 7 of 41 cases (17.1%) were detected among the IMLP-positive group. The 2 Epstein-Barr virus serologic tests by enzyme-linked immunosorbent assay could be a feasible alternative for NPC screening in endemic areas. Further follow-up is needed to examine whether screening has an effect on decreasing mortality from NPC in these areas.

A randomized trial of induction chemotherapy plus concurrent chemoradiotherapy versus induction chemotherapy plus radiotherapy for locoregionally advanced nasopharyngeal carcinoma

The aim of this randomized study was to compare the efficacy of induction chemotherapy plus concurrent chemoradiotherapy (IC+CCRT) versus induction chemotherapy plus radiotherapy (IC+RT) for patients with locoregionally advanced nasopharyngeal carcinoma. From August 2002 to April 2005, 408 patients were randomly divided into two groups: an IC+CCRT group and an IC+RT group. Patients in both groups received the same induction chemotherapy: two cycles of floxuridine (FuDR)+carboplatin (FuDR, 750 mg/m(2), d1-5; carboplatin, area under the curve [AUC]=6). The patients received radiotherapy 1 week after they finished the induction chemotherapy. The patients in the IC+CCRT group also received carboplatin (AUC=6) on days 7, 28, and 49 of radiotherapy. Eight patients did not meet the inclusion criteria, and the remaining 400 cases were analyzed. Grade III or IV toxicity was found in 28.4% of the patients in the IC+CCRT group and 13.1% of those in the IC+RT group (P<.001). Five-year overall survival rates were 70.3% and 71.7% (P=0.734) in the IC+CCRT and IC+RT groups, respectively. No significant differences in failure-free survival, locoregional control, and distant control were found between the two groups. Compared with the IC+RT program, the IC+CCRT program used in the present study did not improve the overall survival and failure-free survival in patients with locoregionally advanced nasopharyngeal carcinoma. Using carboplatin in the concurrent chemoradiotherapy was not suitable for nasopharyngeal carcinoma.

Evaluation of plasma Epstein‐Barr virus DNA load to distinguish nasopharyngeal carcinoma patients from healthy high‐risk populations in Southern China

The utility of circulating Epstein‐Barr Virus (EBV) DNA as a tumor marker for nasopharyngeal carcinoma (NPC) detection suggests that it might improve the diagnostic performance of anti‐EBV antibody markers in NPC screening. In this study, the authors evaluated whether circulating EBV DNA load is capable of distinguishing NPC patients from high‐risk individuals who have positive anti‐EBV antibodies.

Prospective validation of the prognostic value of elevated serum vascular endothelial growth factor in patients with nasopharyngeal carcinoma: more distant metastases and shorter overall survival after treatment.

The purpose of this prospective study was to investigate the prognostic value of serum vascular endothelial growth factor (sVEGF) in patients with nasopharyngeal carcinoma (NPC).

Nasopharyngeal carcinoma risk prediction via salivary detection of host and Epstein-Barr virus genetic variants

Genetic susceptibility and Epstein-Barr virus (EBV) infection are important etiological factors in nasopharyngeal carcinoma (NPC). In this study, in southern China, where NPC is endemic, a single nucleotide polymorphism (SNP) in the EBV-encoded RPMS1 gene (locus 155391: G > A [G155391A]) and seven host SNPs (rs1412829, rs28421666, rs2860580, rs2894207, rs31489, rs6774494, and rs9510787) were confirmed to be significantly associated with NPC risk in 50 NPC cases versus 54 hospital-based controls with throat washing specimens and 1925 NPC cases versus 1947 hospital-based controls with buffy coat samples, respectively. We established a strategy to detect the NPC-associated EBV and host SNPs using saliva samples in a single test that is convenient, noninvasive, and cost-effective and displays good compliance. The potential utility of this strategy was tested by applying a risk prediction model integrating these EBV and host genetic variants to a population-based case-control study comprising 1026 incident NPC cases and 1148 controls. Receiver operating characteristic (ROC) curve analysis revealed an area under the curve of the NPC risk prediction model of 0.74 (95% CI: 0.71−0.76). Net reclassification improvement (NRI) analysis showed that inclusion of the EBV SNP significantly improved the discrimination ability of the model (NRI = 0.30, P < 0.001), suggesting the promising value of EBV characteristics for identifying high-risk NPC individuals in endemic areas. Taken together, we developed a promising NPC risk prediction model via noninvasive saliva sampling. This approach might serve as a convenient and effective method for screening the population with high-risk of NPC.

Oral hygiene and risk of nasopharyngeal carcinoma - a population-based case-control study in China

Background: The association between oral health and risk of nasopharyngeal carcinoma (NPC) is largely unknown. Further understanding could shed light on potential pathogenic mechanisms and preventive measures. Methods: We conducted a population-based case–control study in southern China between 2010 and 2014. We enrolled 2,528 incident NPC cases, aged 20–74 years, and 2,596 controls, randomly selected from the total population registers, with frequency matching to the 5-year age and sex distribution of the cases by geographic region. We interviewed subjects using a structured questionnaire inquiring about oral health indicators and potential confounding factors. We used unconditional logistic regression to estimate multivariate-adjusted ORs with 95% confidence intervals (CI). Results: A higher number of filled teeth was associated with an elevated risk of NPC. Individuals with 1 to 3 and more than 3 teeth filled versus none had adjusted ORs of 1.25 (95% CI, 1.06–1.49) and 1.55 (95% CI, 1.13–2.12), respectively (Ptrend = 0.002). Conversely, the adjusted OR for those who brushed teeth twice or more per day versus once or less per day was 0.62 (95% CI, 0.55–0.70). We detected a borderline significant positive association with earlier age at first adult tooth loss. Conclusion: Our study suggested a positive association between some indicators of poor oral health and risk of NPC. Further studies are needed to confirm whether the findings are causal and, if so, to further explain the underlying mechanisms. Impact: Improvement of oral hygiene might contribute to reducing NPC risk. Cancer Epidemiol Biomarkers Prev; 25(8); 1201–7. ©2016 AACR.

Hepatitis B Virus Infection and Risk of Nasopharyngeal Carcinoma in Southern China

Background: Whether or not hepatitis B virus (HBV) infection plays a role in the development of nasopharyngeal carcinoma (NPC) is largely unknown. Our study aimed to assess the association between HBV infection and the risk of NPC in Southern China. Methods: We conducted a case–control study including 711 NPC cases and two groups of controls. The first control group consisted of 656 individuals with other benign tumors unrelated to HBV infection and the second group consisted of 680 healthy population controls. Multivariable ORs and corresponding 95% confidence intervals (CI) for NPC were estimated by logistic regression. Results: Patients with NPC had higher prevalence of antibodies against hepatitis B core antigen–positive [anti-HBc-(+); 47.26%] compared with either benign tumor controls (39.33%; P < 0.01) or healthy controls (41.18%; P = 0.04). In multivariable models adjusting for a set of risk factors for NPC, anti-HBc-(+) was significantly associated with a higher risk of NPC [adjusted OR (AOR), 1.40; 95% CI, 1.12–1.74 compared with the benign tumor controls and AOR, 1.48; 95% CI, 1.05–2.08 compared with the healthy controls]. The association was not modified by hepatitis B surface antigen (HBsAg) status. Finally, compared with the healthy controls, individuals with both anti-HBc-(+) and EBV antibodies had largely increased risk of NPC (AOR, 141.82; 95% CI, 68.73–292.62). Conclusion: Our study suggests that HBV infection is associated with NPC risk in Southern China. Impact: Prevention for HBV infection may play a role in the development of NPC. Cancer Epidemiol Biomarkers Prev; 24(11); 1766–73. ©2015 AACR.

[Significance of cell-free Epstein-Barr virus DNA in monitoring prognosis of nasopharyngeal carcinoma].

ObjectiveIt has been reported that cell-free Epstein-Barr virus (EBV-DNA) in plasma was useful in diagnosing and monitoring nasopharyngeal carcinoma (NPC). The current study was designed to evaluate the significance of EBV-DNA in monitoring the prognosis of nasopharyngeal carcinoma and comparing its significance with that of plasma VCA/lgA and EA/lgA levels.MethodsE8V -DNA, VCA/lgA, and EA/lgA levels in plasma were determined in NPC patients with different prognosis after radiotherapy, including 30 distant metastatic patients, 22 local recurrence patients and 24 individuals with remission who had been followed-up for more than 2 years after treatment. EBV-DNA was determined using a real-time quantitative PCR system, and levels of VCA/lgA and EA/lgA were measured using standard immunofluorescence. In a cohort study, the indexes were determined after different radiation periods for the 20 new cases of nasopharyngeal carcinoma.ResultsThe median plasma EBV-DNA concentration was 135,100 copies/ ml (interquartile range: 5,525-1,003 750) in metastatic group, 20,500 copies/ ml (interquartile range: 0 -58,500) in the local recurrence group and 0 copies/ml (interquartile range: 0-0) in the continuous remission group (P< 0.05). The levels of VCA/lgA and EA/lgA showed no significant differences among the different groups. The high level of EBV-DNA concentration in the metastatic group was more than that in the local recurrence group. A level of 1,000,000 copies/ml of EBV DNA was an indication of distant metastasis of the NPC patients with a sensitivity of 27.3%. However, the sensitivity was 0 in the local recurrence group. For the 20 new patients, EBV -DNA concentration gradually decreased during the radiation period. Before radiation there were 32,050 copies/ml (interquartile range: 3,880-317,750), 0 copies/ml (interquartile range: 0-14 375) after a 40 Gy radiation dose and 0 copies/ml (interquartile range: 0-2940) after the radiation was finished (P< 0.05). However, the levels of VCA/lgA and EA/lgA showed no significant difference.ConclusionDetermination of plasma cell -free EBV -DNA level is more valuable than evaluation of VCA/lgA and EA/lgA for monitoring the prognosis of NPC patients.