Serum EBV DNA as a biomarker in primary nasopharyngeal carcinoma of Indian origin

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a unique tumor due to its etiology and endemic distribution. Ethnic and regional factors are found to strongly influence the risk of disease; however, there have been no well-conducted studies on Indian patients. The present study assesses the relationship between Epstein-Barr Virus (EBV) and sporadic Indian NPC and the role of serum EBV DNA in NPC detection. METHODS: Primers directed against non-polymorphic Epstein-Barr nuclear antigen-1 (EBNA-1) gene were used to detect the presence of EBV DNA from fresh tissue and serum in NPC, using PCR. RESULTS: EBV DNA was detected in 69% of the biopsies and 58% of the serum of the NPC patients. With respect to histology, WHO Type III NPC, WHO Type II tumors and WHO I tumors showed 100%, 72.2% and 33% EBV positivity, respectively. EBV positivity was also observed in 23% (6/26) of benign samples. All biopsies of patients with positive serum samples were positive for EBV DNA. CONCLUSION: EBV infection was found in sporadic NPC of South Indian origin, which confirms the etiological role of EBV in NPC. Detection of EBNA-1 in the serum and corresponding tissues of NPC patients suggests that the serum EBV DNA originates from NPC and also indicates the benefit of circulating viral DNA as an early marker in the diagnosis of NPC. Serum DNA-PCR methods can be extrapolated to follow-up studies involving tumor regression or to assess the response to various therapies.     

Association of Epstein-Barr virus with tumor cell proliferation: clinical implication in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is characterized by its association with Epstein-Barr virus (EBV) infection. Unlike other upper aerodigestive tract squamous cell carcinomas, clinical and pathologic features are unable to predict outcome in NPC. EBV has been demonstrated to have transforming potential in B-cell systems so that its infection can rapidly and efficiently induce sustained lymphocyte proliferation in vitro. However, the relationship between cell proliferation and EBV infection in NPC has not been previously reported. This study was designed to determine the association of EBV infection and NPC tumor cell proliferation. Cell proliferation index, as measured by two markers, PCNA and Ki-67, were moderately correlated (r=0.534, p=0.033). Quantitative analysis of EBV positivity was highly correlated with both cell proliferation indices (r=0.802, p=0.0039 and r=0.720, p=0.0174 for PCNA and Ki-67, respectively). TNM staging did not demonstrate prognostic significance. NPC patients whose tumors were EBV positive demonstrated increased survival compared with patients whose tumors were EBV negative (p=0.043). These results indicate that EBV infection may regulate cell proliferation in NPC and the presence of EBV can be used as a positive prognostic factor.     

Disparity of sensitivities in detection of radiation-na?ve and postirradiation recurrent nasopharyngeal carcinoma of the undifferentiated type by quantitative analysis of circulating Epstein-Barr virus DNA1,2.

PURPOSE: The purpose of this research was to compare the sensitivities of plasma EBV DNA in detection of postirradiation locally recurrent nasopharyngeal carcinoma (NPC), postirradiation distant metastatic NPC, and radiation-na?ve NPC. EXPERIMENTAL DESIGN: Twenty-four patients with postirradiation local recurrence of NPC were assessed for plasma EBV DNA levels by a real-time quantitative PCR system. The results were compared with those of a cohort of 140 patients with newly diagnosed NPC and with those of 25 patients with distant metastatic relapse. EBV-encoded RNA positivity was also assessed in locally recurrent tumors and newly diagnosed tumors with undetectable plasma EBV DNA levels. RESULTS: Postirradiation locally recurrent tumors were associated with a significantly lower rate of detectable plasma EBV DNA compared with radiation-na?ve tumors of comparable stage [stage I-II tumors: 5 of 12 (42%) versus 47 of 51 (92%), P = 0.0002; stage III-IV tumors: 10 of 12 (83%) versus 88 of 89 (99%), P = 0.01; Fisher's exact test], and compared with distant metastatic recurrences [15 of 24 (63%) versus 24 of 25 (96%), P < 0.02; Fisher's exact test]. The median EBV DNA level in patients with detectable EBV DNA was also significantly lower in locally recurrent tumors than in radiation-na?ve tumors. All of the tissue samples of tumors associated with undetectable EBV DNA levels, where available, were EBV-encoded RNA positive. CONCLUSIONS: The sensitivity of EBV DNA in the detection of tumors regrowing from an irradiated site is much lower than that from a radiation-na?ve site. Although plasma EBV DNA is very effective in detecting distant metastatic relapse of NPC, it cannot be relied on as the sole surveillance tool for detection of local relapse.     

Vesicle-bound EBV-BART13-3p miRNA in circulation distinguishes nasopharyngeal from other head and neck cancer and asymptomatic EBV-infections

Cell-free microRNA (miRNA) in biofluids released by tumors in either protein or vesicle-bound form, represent promising minimally-invasive cancer biomarkers. However, a highly abundant non-tumor background in human plasma and serum complicates the discovery and detection of tumor-selective circulating miRNAs. We performed small RNA sequencing on serum and plasma RNA from Nasopharyngeal Carcinoma (NPC) patients. Collectively, Epstein Barr virus-encoded miRNAs, more so than endogenous miRNAs, signify presence of NPC. However, RNAseq-based EBV miRNA profiles differ between NPC patients, suggesting inter-tumor heterogeneity or divergent secretory characteristics. We determined with sensitive qRT-PCR assays that EBV miRNAs BART7-3p, BART9-3p and BART13-3p are actively secreted by C666.1 NPC cells bound to extracellular vesicles (EVs) and soluble ribonucleoprotein complexes. Importantly, these miRNAs are expressed in all primary NPC tumor biopsies and readily detected in nasopharyngeal brushings from both early and late-stage NPC patients. Increased levels of BART7-3p, BART9-3p and particularly BART13-3p, distinguish NPC patient sera from healthy controls. Receiver operating characteristic curve analysis using sera from endemic NPC patients, other head and neck cancers and individuals with asymptomatic EBV-infections reveals a superior diagnostic performance of EBV miRNAs over anti-EBNA1 IgA serology and EBV-DNA load (AUC 0.87–0.96 vs 0.86 and 0.66 respectively). The high specificity of circulating EBV-BART13-3p (97%) for NPC detection is in agreement with active secretion from NPC tumor cells. We conclude EV-bound BART13-3p in circulation is a promising, NPC-selective, biomarker that should be considered as part of a screening strategy to identify NPC in endemic regions.     

HHV-6感染在鼻咽癌发病中的意义

目的：探计鼻咽癌组织中人疱疹病毒6型(HHV—6)在鼻咽癌(Nasopharyngeal carcinoma，NPC)发病中的意义。方法：PCR检测27例正常鼻咽组织、21例异型增生及42例鼻咽癌组织中HHV一6DNA和EB病毒(Epstein—barr vims，EBV)DNA存在状况，用免疫组化检测36例NPC组织中EBVLMPl蛋白的表达及40例NPC组织中p53基因的表达。结果：异型增生和NPC组织中HHV一6 DNA的阳性率分别为4．7％和26．2％，EBV DNA分别为4．6％和95．2％；正常鼻咽组织不存在HHV一6DNA，EBVDNA为25．9％。NPC组织中EBV—LMPl蛋白阳性率为47．2％，HHV一6阳性NPC中LMN表达阳性率(81．8％)显著高于HHV一6阴性者(32．0％)。HHV一6阳性与阴性的NPC中p53表达的阳性率无显著性差异，但HHV—6阳性的NPC中p53表达强度显著性增高。结论：NPC组织中存在HHV—6的感染，与EBV—LMP1蛋白表达上调呈正相关。提示在NPC的发生中HHV—6可能直接参与和(或)通过上调EBV—LMP1的表达而起作用，并可能参与鼻咽癌发病中p53过表达的调控。     

Profiling of Epstein-Barr virus-encoded microRNAs in nasopharyngeal carcinoma reveals potential biomarkers and oncomirs

BACKGROUND:

Epstein‐Barr virus (EBV) microRNAs are abundant in nasopharyngeal carcinoma (NPC) tumors. With recent advances in serum microRNA detection, the distinct presence of EBV microRNAs in serum could aid in screening endemic regions for NPC. A proposed network of genes targeted by these microRNAs could also shed light on EBV‐associated tumorigenesis.

METHODS:

MicroRNA microarray profiling of 5 paired NPC biopsies was followed by validation of 12 up‐regulated EBV microRNAs (BART1‐3p, 2‐5p, 5, 6‐5p, 6‐3p, 7, 8, 9, 14, 17‐5p, 18‐5p, 19‐3p) in 15 additional cases by real‐time polymerase chain reaction. Tumor (cellular) and serum microRNA copy numbers from the same 15 patients were correlated. Expression of the same microRNAs were also examined in EBV‐positive cell lines C666 and NP460hTERT+EBV. Bioinformatic tools helped predict cellular target genes, which were later confirmed by gene expression analysis.

RESULTS:

The authors' high‐throughput approach shows that EBV microRNAs are generally more up‐regulated than microRNAs of human origin. Twenty‐nine of 39 EBV microRNAs were significantly up‐regulated in tumor versus their nontumor biopsies (P < .05). Upon successfully validating 12 selected EBV microRNAs in 15 additional paired NPC cases, the authors found that their distinct presence in the serum of NPC patients positively correlated with cellular copy numbers of EBV microRNAs. Further investigation of potential EBV microRNA target genes revealed inhibition of tumor suppressor genes (eg, PTEN) and extensive deregulation of several pathways frequently involved in NPC (eg, Wnt signaling).

CONCLUSIONS:

Increasing knowledge of host‐virus interaction via microRNAs may provide feasible explanations underlying NPC tumorigenesis along with the development of biomarkers for screening high‐risk populations. Cancer 2012;. © 2011 American Cancer Society.     

EGR-1与p53，p16，Cyclin D1在鼻咽癌中的表达及意义

 目的 探讨早期生长反应基因（EGR-1）与p53，p16，Cyclin D1在鼻咽癌中的表达及其意义。方法 应用免疫组化SABC法检测29例鼻咽黏膜慢性炎组织、45例鼻咽癌组织、24例鼻咽癌颈部淋巴结转移灶中EGR-1与p53，p16，Cyclin D1表达。结果 鼻咽癌原发灶及其颈部淋巴结转移灶中EGR-1表达较鼻咽黏膜慢性炎降低，p53，Cyclin D1表达则增高，差异有统计学意义（P＜0.05）；p16在三种病变中的表达差异无统计学意义（P＞0.05）。结论 EGR-1的表达降低与p53，Cyclin D1的高表达可能与鼻咽癌的发生、发展有关；p16可能在鼻咽癌的发生、发展中不起作用。     

EBV-miR-BART10-3p facilitates epithelial-mesenchymal transition and promotes metastasis of nasopharyngeal carcinoma by targeting BTRC

Epstein-Barr virus (EBV) infection is closely associated with tumorigenesis and development of nasopharyngeal carcinoma (NPC), but the underlying molecular mechanisms remain poorly understood. It has been recently reported that EBV encodes 44 mature miRNAs, some of which were found to promote tumor development by targeting virus-infected host genes or self-viral genes. However, few targets of EBV encoded-miRNAs that are related to NPC development have been identified to date. In this study, we revealed that in NPC cells, EBV-miR-BART10-3p directly targets BTRC gene that encodes βTrCP (beta-transducin repeat containing E3 ubiquitin protein ligase). We found that EBV-miR-BART10-3p expression in clinical samples from a cohort of 106 NPC patients negatively correlated with BTRC expression levels. Over-expression of EBV-miR-BART10-3p and down-regulation of BTRC were associated with poor prognosis in NPC patients. EBV-miR-BART10-3p promoted the invasion and migration cabilities of NPC cells through the targeting of BTRC and regulation of the expression of the downstream substrates β-catenin and Snail. As a result, EBV-miR-BART10-3p facilitated epithelial-mesenchymal transition of NPC. Our study presents an unreported mechanism underlying EBV infection in NPC carcinogenesis, and provides a potential novel biomarker for NPC diagnosis, treatment and prognosis.     

Nasopharyngeal brush biopsies and detection of nasopharyngeal cancer in a high-risk population.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is an important tumor in many countries. Ethnic and regional factors strongly influence disease risk. NPC is usually diagnosed late in disease development, and 10-year survival rates are as low as 10%. Epstein-Barr virus (EBV), a possibly causative agent, is present in all cells of essentially all undifferentiated NPCs. We wished to determine the following: 1) whether an ambulatory nasopharyngeal brush biopsy could provide sufficient tumor cell DNA for the detection of EBV and 2) whether the detection of EBV in this locale reflects the presence of tumor cells or simply EBV carrier status. METHODS: We collected nasopharyngeal tissue via ambulatory brush biopsies from 21 patients with newly diagnosed NPC and from 157 subjects with other otolaryngologic complaints. The majority of study subjects were from high-risk populations. Sample DNA was analyzed for the presence of EBV genomic sequences by use of the polymerase chain reaction (PCR). RESULTS: Ninety-six percent of samples yielded sufficient DNA for PCR amplification. Nineteen of 21 patients with NPC brushed positive for EBV DNA, while all but two (1.3%) of 149 informative control subjects were negative for EBV (two-sided P<.0001). One of the EBV-positive control subjects had an EBV-positive inverted sinonasal papilloma; the other EBV-positive control subject exhibited no overt clinical disease. CONCLUSION: Demonstration of EBV DNA in nasopharyngeal brush biopsy specimens detects NPC with a sensitivity of at least 90% (95% confidence interval = 89.63%-91.32%) and a specificity of approximately 99% (95% confidence interval = 98.64%-98.68%). This technique merits further testing as a possible ambulatory screening strategy in high-risk populations.     

The use of Doppler ultrasound in evaluation of breast cancer metastasis to axillary lymph nodes

The formation of microvessels in tumors by angiogenesis is considered to be an important prognostic factor, and closely correlates with lymph node metastasis. We used color Doppler ultrasound to examine the relationship between the amount of blood vessels in tumors and pulsatility index (PI), and tumor size in breast cancers, with and without regional lymph node metastasis. Doppler ultrasound was performed on 80 patients with breast cancer prior to surgery. The concentration of vascular endothelial growth factor (VEGF) within the tumors was measured following surgery in 42 cases chosen at random. In the negative metastatic nodes group, the number of vessels in the tumor correlated positively with tumor diameter. In the positive metastatic nodes group, however, the number of blood vessels in the tumor did not correlate with tumor diameter. Differences in tumor vascularity between node positive and negative groups were useful in determining the status of node metastasis in subsequent analysis. Fifteen of 17 cases of tumors that measured <20 mm, and in which there were no blood vessels, were node-negative. There were no node-negative tumors measuring >20 mm in diameter (p=0.003). Conversely, in nodes with positive metastasis, blood vessels were observed in 5 of 7 tumors that measured <15 mm in diameter (p=0.019). These findings may be useful in estimating the likelihood of metastasis to regional lymph nodes. PI was directly proportional to tumor size in the negative nodes group (r=0.47). There was no such correlation in the positive nodes group. There was no correlation between VEGF concentration in the tumor and the number of blood vessels in that tumor. In conclusion color Doppler analysis of blood vessels appears to be useful in predicting lymph node metastasis, especially for small tumors.     

Induction therapy of locally-advanced nasophayngeal cancer

Unlike most head and neck tumors, nasophayngeal cancer (NPC) is characterized by such ep-idemiological and histological features as massive lympho- and hematogenic metastasizing and enhanced sensitivity to conservative therapy. More than 80% of diagnosed tumors are grade III-IV and, therefore, are more resistant to irradiation; they have a worse prognosis. Our method of induction chemotherapy (docetaxel, doxorubicin, cisplatin) was used in treating 50 patients with locally-advanced NPC: complete response--88% (44) [complete resorption--48% (24)]. Lymphadenectomy was carried out in 12 cases of primary metastatic lesions N2-3 in the elymph nodes of the neck on completion of all stages of combined (induction + radiation) therapy. Metastases to the regional lymph nodes were detected in 10 patients.     

血管内皮生长因子C、D在鼻咽癌组织中的表达及其临床意义

背景与目的:血管内皮生长因子C(vascular endothelial growth factor-C,VEGF-C)和D(vascular endothelial growth factor-D,VEGF-D)是目前已鉴定出的淋巴管生长因子,有研究表明肿瘤组织中VECF-C或VEGF-D过表达与淋巴转移有关.本研究旨在探讨鼻咽癌组织中VEGF-C和VEGF-D的表达情况及其临床意义.方法:采用免疫组化SP法检测66例鼻咽癌组织中VEGF-C和VEGF-D的表达情况,同时检测血管内皮生长因子受体3(vascular endotheliaI growth factor receptor-3,VEGFR-3)和CD34染色情况并计数微淋巴管密度(lymphatic microvessel density,LMVD)和微血管密度(microvessel density,MVD).结果:VEGF-C高表达率在鼻咽癌组织中(54.5%)较鼻咽非肿瘤组织中(26.3%)高(P＜0.05);鼻咽癌伴区域淋巴结转移或T分期晚者,VEGF-C高表达率增高,单因素及多因素Logistic回归分析均表明区域淋巴结转移与VEGF-C高表达相关(P＜0.05),但VEGF-C高表达与性别、年龄、5年生存率、LMVD、MVD等因素无关(P＞0.05).VEGF-D阳性表达率在鼻咽癌组织中(69.7%)较鼻咽非肿瘤组织中(42.1%)高(P＜0.05);鼻咽癌中VEGF-D阳性表达与性别、年龄、T分期、区域淋巴结转移、LMVD、MVD等因素无关(P＞0.05),但与VEGF-C高表达显著正相关(P＜0.01),VEGF-D阳性表达者5年生存率(50.0%)显著低于VEGF-D不表达者(85.0%)(P＜0.01).结论:鼻咽癌中VEGF-C高表达与区域淋巴结转移密切相关;VEGF-D阳性表达与区域淋巴结转移无关,但与VEGF-C高表达正相关,且与5年生存率密切相关.     

NO期鼻咽癌颈淋巴结区域预防照射方式的探讨

背景与目的:鼻咽癌一侧或双侧颈部淋巴结阴性者颈部的区域预防照射范围及剂量尚无定论。本研究通过回顾性分析,探讨鼻咽癌影像学诊断N0期患者颈部预防野照射方式,并分析颈部淋巴结复发因素及预后因素。方法:收集2002年1月至2004年12月205例N0期鼻咽癌患者资料,治疗前均行鼻咽部和颈部影像学检查。采用直线加速器产生的6～8MV高能X线,以面颈联合野为主的放疗技术,鼻咽原发灶照射剂量为60～80Gy,颈部剂量为46～64Gy。常规分割、连续照射。按颈部预防照射范围将患者分为两组,半颈预防组和全颈预防组。60例进行了化疗。随访时间3～68个月,中位随访时间44个月。累积生存率采用Kaplan-Meier计算,对生存率的差异采用log-rank进行显著性检验,多因素分析采用Cox风险比例模型前进法。结果:205例N0期鼻咽癌患者,3年总生存率及无瘤生存率分别为92.9%、91.9%。半颈、全颈预防组淋巴结复发率分别为2.27%、0,T1、T2、T3、T4期患者的颈部复发率分别为0、3.08%、0、0,鼻咽无复发时、复发时的颈部淋巴结复发率分别为1.03%、0,各组淋巴结复发率比较差异均无统计学意义(P>0.05)。半...     

Flow cytometry as a prognostic predictor in gastric linitis plastica

Gastric linitis plastica (GLP) is a diffusely infiltrating carcinoma of the stomach that is usually diagnosed in an advanced stage and associated with poor prognosis. Recent studies to evaluate ploidy of these tumors are not conclusive. We undertook a retrospective study of 43 surgically treated patients with GLP (27 males, 16 females, mean age 65 years) to see if ploidy could be used to predict outcome. Flow cytometric DNA analysis was performed on paraffin-embedded tissue using the modified Hedley technique. Mean follow-up interval was 11 months (1–72 months) with 18 (42%) alive at end of study. The remaining 25 (58%) died with a mean survival of 7 months. Lymph node status was positive in 31 (70%) and negative in 12 (30%) of patients. Twenty-nine (67%) of tumors were diploid; 14 (33%) were aneuploid. Statistical analysis revealed overall surcvival correlated significantly (P = 0.04) only with lymph node status. Diploid tumors had 18 (60%) positive and 11 (40%) negative lymph nodes, whereas aneuploid tumors had 13 (93%) positive and 1 (7%) negative nodes. DNA content correlated significantly (P = 0.05) with lymph node status, but not with overall survival. Tumors with positive lymph nodes were 18 (51%) diploid and 13 (42%) aneuploid; tumors with negative nodes were 11 (92%) diploid and 1 (8%) aneuploid. Conclusions: The majority of GLP tumors manifest diploid characteristics, and the presence or absence of lymph node metastasis is a major determinant in overall survival. © 1994 Wiley-Liss, Inc.     

Plasma Epstein-Barr virus DNA and residual disease after radiotherapy for undifferentiated nasopharyngeal carcinoma

BACKGROUND: Epstein-Barr virus (EBV) DNA can be detected and quantified in the plasma of patients with EBV-related tumors, such as nasopharyngeal carcinoma (NPC). Although NPC at early stages can be cured by radical radiotherapy, there is a high recurrence rate in patients with advanced NPC. The pretreatment level of circulating EBV DNA is a prognostic factor for NPC, but the prognostic value of post-treatment EBV DNA has not been studied. We designed a prospective study in Hong Kong, China, to investigate the value of plasma EBV DNA as a prognostic factor for NPC. METHODS: One hundred seventy NPC patients, without metastatic disease at presentation, were treated with a uniform radiotherapy protocol. Circulating EBV DNA was measured by real-time quantitative polymerase chain reaction before treatment and 6-8 weeks after radiotherapy was completed. Risk ratios (RRs) were determined with a Cox regression model, and associations of various factors with progression-free and overall survival and recurrence rates were determined with a stepwise Cox proportional hazards model. All statistical tests were two-sided. RESULTS: Ninety-nine percent of patients achieved complete clinical remission. Levels of post-treatment EBV DNA dominated the effect of levels of pretreatment EBV DNA for progression-free survival. The RR for NPC recurrence was 11.9 (95% confidence interval [CI] = 5.53 to 25.43) for patients with higher post-treatment EBV DNA and 2.5 (95% CI = 1.14 to 5.70) for patients with higher pretreatment EBV DNA. Higher levels of post-treatment EBV DNA were statistically significantly associated with overall survival (P<.001; RR for NPC recurrence = 8.6, 95% CI = 3.69 to 19.97). The positive and negative predictive values for NPC recurrence for a higher level of post-treatment EBV DNA were 87% (95% CI = 58% to 98%) and 83% (95% CI = 76% to 89%), respectively. CONCLUSION: Levels of post-treatment plasma EBV DNA in patients with NPC appear to strongly predict progression-free and overall survival and to accurately reflect the post-treatment residual tumor load.     

Detection of cell free Epstein-Barr virus DNA in sera from patients with nasopharyngeal carcinoma

BACKGROUND: The detection of tumor-derived DNA within the circulation of patients with malignant disease using polymerase chain reaction (PCR)-based strategies has opened a new avenue for the diagnosis and monitoring of these patients. Because of the universal association of Epstein-Barr virus (EBV) with the nonsquamous type of nasopharyngeal carcinoma (NPC; World Health Organization types II and III), the detection of cell free EBV DNA in sera from patients with NPC may be a valuable tool for monitoring the progress of tumors or to provide advanced warning of tumor recurrence. METHODS: Serum samples were obtained from different patients, and cell free EBV DNA was detected with a conventional PCR approach. A total of 134 patients were sampled, including 36 patients with primary NPC, 28 control patients, 18 patients suffering from locoregional recurrence, 7 patients with distant metastasis, and 45 patients with NPC in clinical remission. A conventional PCR approach employing standard 35-cycle and 50-cycle reactions was used to detect cell free EBV genomes. Results from the two PCR cycles were compared to provide a semiquantitative picture of the relative quantity of EBV genome in each serum sample. RESULTS: The EBV DNA detection rates, i.e., the rates of positive detection, for 35-cycle and 50-cycle PCR analyses, respectively, were 38.9% and 75% for patients with primary NPC, 3.5% and 10.7% for control patients, 27.8% and 88.9% for patients with locoregional disease recurrence, 71.4% and 100% for patients with distant metastasis, and 7.1% and 36.5% for patients with disease in clinical remission. The rates of positive detection among patients with active disease all appeared to be significantly greater compared with the rates among patients with disease in clinical remission. Longitudinal data for six patients with recurrent tumors revealed a close correlation between the relative quantity of circulating cell free EBV genomes and the disease course of these patients. The sensitivity, specificity, positive predictive value, and negative predictive value of the 50-cycle PCR analysis for detecting recurrent disease were 92%, 63.5%, 42.6%, and 96.4%, respectively. CONCLUSIONS: This study demonstrated that, by using a 50-cycle PCR-based approach, high sensitivity and high negative predictive value for detecting recurrent disease can be obtained from the detection of the cell free EBV genome in sera from patients with NPC. The 50-cycle PCR analysis, therefore, may provide a simple, clinically useful adjuvant method for monitoring patients with NPC.     

As Evidence-Based Tumorigenic Role of Epstein-Barr Virus miR-BART1-3p in Neurological Tumors

Introduction: Central nervous system tumors are a diverse group of tumors that account for 2% of all adult cancers and 17% of childhood malignancies. Several internal and external risk factors are involved in the development of this cancer such as viral infections. The aim of this study was to the determination of the EBV infection frequency and the expression level of miR-122 and miR-BART in CNS tumors samples. Methods: One hundred and thirty-eight  fresh tissue sample (106 case and 32 control) was collected from CNS specimens. The presence of Epstein-Barr virus (EBV) DNA was examined by PCR assay and the expression level of miR-122 and miR-BART were evaluated by using real-time PCR assay in CNS tissue samples. Results: EBV DNA was detected in 17% (18 of 106) of tumors tissue samples and 6.4% (2 of 32) of control samples. according to results, there was a significant relationship between the presence of EBV-DNA with CNS tumors. Additionally, the expression level of miR-122 was significantly downregulated in the EBV-positive sample compared to that of the EBV-negative sample. Also, the level of EBV-BART1-3p expression was significantly higher in EBV-positive tumors samples than EBV-positive normal samples. Conclusion: The results of this study suggest that the EBV could change the condition of cancer cells by altering the expression of miR-122 and EBV-BART1-3p and maybe contribute to the development of cancer cells. However, the role of viral infections in CNS cancer requires further studies.     

Prognostic role of Ebstein-Barr virus latent membrane protein-1 and interleukin-10 expression in patients with nasopharyngeal carcinoma

PURPOSE: We aimed to investigate Ebstein-Barr virus (EBV) latent membrane protein-1 (LMP-1) and Interleukine-10 (IL-10) expression in nasopharyngeal carcinoma (NPC) patients and to evaluate their prognostic significance. MATERIAL AND METHODS: Between 1993 and 1999, 166 patients were treated with the diagnosis of nonmetastatic NPC at our department. The expression of LMP-1 and IL-10 was investigated by using an immunohistochemical approach in 74 (53 male, 21 female) patients whose paraffin embedded tissue samples were available. A detailed histopathological analysis including degree of apoptosis and lymphocyte infiltration was made and all patients were reclassified according to the World Health Organization (WHO) classification. Univariate, multivariate, and logistic regression analyses were performed using all clinical and pathological prognostic factors. All patients were treated with radiotherapy +/- chemotherapy. Follow-up ranged between 12 and 80 months (median: 32). RESULTS: The histopathological diagnosis was WHO-I in 1 (1.3%), WHO-II in 15 (20.2%), and WHO-III in 58 (79.5%) patients. There were 38 (51%) patients with IL-10 expression and 44 (61%) patients with LMP-1 expression. Twenty-seven (36.4%) patients were found to be both IL-10 and LMP-1 positive. There were significantly more N0 disease in patients without LMP-1 expression compared to LMP-1 positive patients (65% vs. 35%, p = 0.01). The logistic regression analysis showed advanced nodal involvement to be the major parameter affecting the expression of IL-10 (p = 0.03). Three-year overall survival (OS), locoregional relapse free survival (LRRFS), and distant metastasis free survival (DMFS) rates were 67.8%, 84.4%, and 74.3%, respectively, for the whole group. On univariate analysis, LRRFS was significantly lower in WHO-III patients, DMFS was significantly lower in advanced nodal disease and IL-10 negative patients, and OS was significantly lower in WHO-III patients. Multivariate analysis showed that WHO-III and T2 patients were significantly associated with lower OS and N3 patients were significantly associated with lower DMFS. CONCLUSION: We observed a high rate (61%) of EBV (LMP-1 positive) and NPC association in our patients. LMP-1 positive tumors were found to be more prone to invade lymph nodes. Patients with negative IL-10 expression had more advanced N disease. We did not find a prognostic significant role of IL-10 and EBV LMP-1 on survival in multivariate analysis.     

原发鼻咽癌及颈部淋巴结转移灶中VEGF-C和E-cadherin的表达

目的 探讨血管内皮生长因子C（vascular endothelial growth factor C,VEGF-C）和E-cadherin在鼻咽癌组织及其淋巴结转移灶中的表达及意义.方法 采用免疫组化SP法检测45例鼻咽癌组织及28例相应淋巴结转移灶中VEGF-C和E-cadherin的表达.结果 VEGF-C和E-cadherin在45例鼻咽癌组织中阳性率分别为40.00%和55.56%,在28例淋巴结转移灶中阳性率分别为78.57%和25.00%,两者在鼻咽癌组织和鼻咽癌淋巴结转移组织中阳性率比较均有显著性差异（P＜0.05）;淋巴结转移的鼻咽癌组织中VEGF-C阳性率明显高于无淋巴结转移组;淋巴结转移的鼻咽癌组织中E-cadherin阳性率明显低于无淋巴结转移组织.结论 VEGF-C高表达或E-cadherin低表达可能与鼻咽癌淋巴结转移密切相关.