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Autophagy has an important role in the pathogenesis of plasma cell development and multiple myeloma (MM); however, the prognostic role of autophagy-related genes (ARGs) in MM remains undefined. In the present study, the expression profiles of 234 ARGs were obtained from a Gene Expression Omnibus dataset (accession GSE24080), which contains 559 samples of patients with MM analyzed with 54,675 probes. Univariate Cox regression analysis identified 55 ARGs that were significantly associated with event-free survival of MM. Furthermore, a risk score with 16 survival-associated ARGs was developed using multivariate Cox regression analysis, including ATIC, BNIP3L, CALCOCO2, DNAJB1, DNAJB9, EIF4EBP1, EVA1A, FKBP1B, FOXO1, FOXO3, GABARAP, HIF1A, NCKAP1, PRKAR1A and SUPT20H, was constructed. Using this prognostic signature, patients with MM could be separated into high- and low-risk groups with distinct clinical outcomes. The area under the curve values for the receiver operating characteristic curves were 0.740, 0.741 and 0.712 for 3, 5 and 10 years prognosis predictions, respectively. Notably, the prognostic role of this risk score could be validated with another four independent cohorts (accessions: GSE57317, GSE4581, GSE4452 and GSE4204). In conclusion, ARGs may serve vital roles in the progression of MM, and the ARGs-based prognostic model may provide novel ideas for clinical applications in MM.

Aim The purpose of this study was to gain a better understanding of systemic lupus erythematosus (SLE) in Hakka populations. Methods We studied the demographic, clinical and laboratory characteristics in a cohort of 552 SLE patients diagnosed at the Rheumatology Department in MeiZhou People's Hospital from January 2008 to December 2012. There were 495 women and 57 men (8.7 : 1) with a mean age of 35.3 years (range 12–78 years). The mean age at disease onset and the mean disease duration were 31.8 ± 14.4 years and 3.3 ± 2.8 years, respectively. Results The most common clinical manifestations were arthritis (61.6%), followed by malar rash (52.7%), photosensitivity (22.8%), mouth ulcers (17.0%) and discoid lupus (14.7%). The prevalence was 46.7% for nephritis (by biopsy), 18.3% for pleuritis, 15.6% for pericarditis and 4.9% for neuropsychiatric manifestations. The most common hematological manifestations were anemia (63.8%), followed by leucopenia (29.0%) and thrombocytopenia (14.9%). Antinuclear antibodies were detected in 99.8% of patients, followed by anti-double-stranded DNA (81.3%), anti-SSA (Sjogren's syndrome antigen A)/Ro (58.7%), anti-ribonucleoprotein (36.8%), anti-Sm (35.7%), and anti-SSB/La (15.0%). Anti-cardiolipin immunoglobulin G (IgG) and IgM were detected in 18.3% and 14.1% of patients, respectively. Active disease and infections were the two major causes of death. Conclusion The clinical and immunological characteristics of the SLE patients in our study place our population in the middle of the spectrum between other Asian and Caucasian populations.

Recent studies showed that the canonical Wnt pathway and miR-29a play important roles in the pathogenesis of bone formation. We studied the levels of miR-29a and messenger RNA (mRNA) of bone turnover markers in the canonical Wnt pathway in ankylosing spondylitis (AS).The levels of miR-29a and mRNA of bone turnover markers in canonical Wnt pathway from peripheral blood mononuclear cells were determined by real-time quantitative polymerase chain reaction in 38 patients with AS and 32 healthy controls. Correlation analysis was conducted between the levels of miR-29a and mRNA and clinical measurements using Spearman's correlation test.Compared to healthy controls, the levels of miR-29a, Dickkopf (DKK)-1, β-catenin and Runx2 mRNA were significantly higher in AS patients (p0.05). In contrast, the levels of Gsk-3β mRNA was significantly lower in AS patients than that in healthy controls (p0.05). Gsk-3β mRNA was positively correlated with β-catenin mRNA expression (p0.05) and no other correlation was observed between any other markers (p0.05). Only DKK-1 mRNA expression was negatively correlated with disease course (p0.05) and no other correlation was observed between markers and clinical measurements (p0.05).The osteoblastic marker miR-29a and downstream mRNA of canonical Wnt signaling was upregulated in AS, suggesting their possible role in new bone formation in AS.

Silica nanotubes were synthesized using multi-walled carbon nanotubes (MWCNTs) as template. The as-obtained samples were characterized by infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscope (FE-SEM) and photoluminescent (PL) spectroscopy. The results indicate that the thickness of the outer walls is about 10 nm and the inner diameter is completely dependent on the size of MWCNTs. The as-fabricated silica nanotubes emit a strong violet light under excitation of 250 nm.

There has been conflicting evidence concerning the best sequence of radiotherapy (RT) and chemotherapy (CT) for advanced non-small-cell-lung-cancer (NSCLC). To investigate whether current clinical trials can clarify this schedule and offer further bases for clinical decision making, we performed a systematic review of 11 trials (2,043 patients; concurrent-1,019, sequential-1,024) that compared concurrent RT-CT with sequential arm in advanced NSCLC patients. Primary end point was overall survival (OS). Pooled median ratios (MRs) and progression-free-survival ratios (FRs) for median survival and progression-free survival (PFS) were calculated using the weighted sum of the log ratio of MR and FR of individual study. Pooled odds ratios (ORs) for the objective response rate, relapse control rate, and toxic events were calculated using the Mantel-Haenszel estimate. Results confirmed that concurrent RT-CT determined a statistically significant increase in median survival time (16.3 vs. 13.9 months; MR = 1.17,95%CI:1.09-1.26), response rate (64.0% vs. 56.3%; OR = 1.38,95%CI:1.10-1.72), and tumor-relapse control (OR = 0.82,95%CI:0.69-0.97), though at the expense of increased hematological toxicity (neutropenia and thrombocytopenia) and non-hematological toxicity (nausea/vomiting, stomatitis, and esophagitis). Similar results were obtained from the sensitivity analysis of all Phase-III/trials designed to evaluate the primary end point of OS. Subgroup analysis revealed that concurrent strategy was mainly associated with improved loco-regional control (OR = 0.68,95%CI:0.52-0.87). However, no difference in PFS is shown. While careful interpretation of our conclusions is required because of potential bias, the present study, to some extent, exhibits the superiority of the concurrent arm over the sequential in the treatment of advanced NSCLC. Further improvements will be obtained by optimizing the conditions for a concurrent regimen.

Based on the elasto-/hydro-dynamic model the dynamic properties of the five-fold symmetry quasicrystals with point groups 5, [Formula: see text] are investigated, by using the finite difference method. The problems including dynamic initiation of crack growth and fast crack propagation of this material are studied. The results show that the phonon–phason coupling effect plays an important role to the dynamic properties of the quasicrystals.

To explore the effect of suppressing BCL-2 expression using RNA interference (RNAi) technique in nasopharyngeal carcinoma cell line CNE1. CNE1 cell lines stably expressing shRNAs targeted bcl-2 and GL3 gene were established and gene expression inhibition was assessed by Western blotting analysis. The effect of suppressing bcl-2 by RNAi on cell growth was studied, the apoptosis induction and the sensitization of CNE1 cells to cisplatin were quantified by MTT assay and flow cytometry. The results showed that: stable transfection of CNE1 cells with vectors expressing shRNAs against bcl-2 decreased the expression of BCL-2 protein; suppression of BCL-2 expression did not affect cell proliferation but could increase the chemosensitivity to cisplatin in CNE1 cells. This will help physicians to make some clinical trials of gene therapy on nasopharyngeal carcinoma by RNAi.

Pathogenesis of nasopharyngeal carcinoma (NPC) is a multistep and multipathway process that cannot be fully explained by a fixed linear progression model. We used distance-based and branching-tree methods to construct more general tree-like models for NPC carcinogenesis from 170 comparative genomic hybridization (CGH) samples previously published in five smaller studies. Imbalances were classified into "overlap regions," each containing the most commonly gained or lost band on each chromosome arm as well as adjacent bands that were gained or lost almost as often. The chromosome abnormalities associated with NPC were -3p26-13 (48.9%), -11q22-25 (38.1%), -16q12-24 (38.1%), -14q24-32 (32.4%), -13q21-32 (22.3%), -9p23-21(21.6%), +12p12 (46%), +12q13-15 (43.9%), +1q22-32 (33.1%), +3q13.1-26.2 (30.2%), and +8q22.1-24.2 (27.3%). NPC can be classified into two groups, one marked by +12p12 and +8q22.1-24.2 and the other by -3p26-13, -11q22-25, -14q24-32, and +1q22-32. The tree models predicted -3p26-13 and +12p12 as early events and +8q22.1-24.2 as a late event. The predictions for -3p26-13 and +8q22.1-24.2 were consistent with previous studies. The prediction for +12p12 is being reported for the first time. Many known NPC-related genes on chromosomal regions of these tree models are discussed, some of which may merit additional study. The potential applications of tree models are also discussed.

NAD(P)H:quinine oxidoreductase 1 (NQO1) is a two-electron reductase that catalyzes quinine to hydroquinone. Variant genotypes of NQO1 Pro187Ser may be related to low enzyme activity and thus are suggested as affecting the risk of lung cancer. Our purpose was to study the NQO1 Pro187Ser polymorphism and the risk of lung cancer.We conducted a PubMed search and a China National Knowledge Infrastructure search using "NAD(P)H quinine reductase 1" ,"lung cancer", and " polymorphism" for articles published from January 1997 to March 2010. For each study, we calculated the crude odds ratios (OR) and 95% confidence intervals (CI) for lung cancer. Summary estimates for crude as well as adjusted OR were calculated with the statistical program stata.The summary OR for carrying one variant allele and the homozygous variant genotype was 1.04 (95%CI, 0.97-1.13). In the Asian population, the summary OR for carrying one variant genotype was 1.09 (95%CI, 0.95-1.25).Through our meta-analysis, we found that the Pro/Ser and Ser/Ser genotypes involving NQO1 were non-significantly associated with lung cancer. In the Asian population, the combined genotype was marginally associated with increased risk of lung cancer. When stratified on gender and smoking, the meta-analysis showed that there was no statistically significant difference between men and women, smokers and non-smokers, respectively.

The role of Chlamydia pneumoniae in the cause of lung cancer is controversial. In this study, we investigated the association between C. pneumoniae immunoglobulin (Ig) G antibodies and risk of lung cancer among non-smoking women. C. pneumoniae IgG antibody levels were compared between 192 adult Chinese women who met the diagnostic criteria of lung cancer and 90 healthy controls. C. pneumoniae IgG antibodies were tested with the use of an enzyme-linked immunosorbent assay. The prevalence of C. pneumoniae IgG seropositivity was 61.98% of cases and 28.89% of controls (P0.05). According to the results of the multiple logistic analysis model, the odds ratios for C. pneumoniae IgG antibody seropositivity, body mass index, and educational levels were 3.919 (P0.001), 0.731 (P= 0.274), and 1.646 (P= 0.069), respectively. C. pneumoniae infection may be a risk factor for lung cancer.

To explore the difference of lingual arterial CT angiography images(CTA) between obstructive sleep apnea hypopnea syndrome (OSAHS) patients and normal subjects, and to investigate the safety of partial glossectomy guided by lingual arteria CT angiography.Seventy-four patients with OSAHS and 10 control adults were included in the study. The lingual upper airway and lingual arterial CT angiography were obtained. The area and the dimensions of lingual upper airway, and the length and thickness of lingua, length of lingual arteria, depth and bilateral lingual arteria spacing were studied. The CT measuring data of OSAHS patients and normal adults were compared. The multinomial logistic regression analysis was used to investigate the main factors which affects the lingual arterial measuring results. Guided by the lingual arterial CT angiography and measuring results, glossectomy was performed in 23 OSAHS patients with lingua hypertrophy.The area and dimensions of lingual airway of OSAHS patients were less than those of control adults, and the length and thickness of lingua of OSAHS were more than those of control adults (t test, P0.05 or P0.01). There were no difference in length of lingual arteria and bilateral lingual arteria spacing between OSAHS patients and control adults. The 3 measured points' depth (x(-) +/- s) of lingual arteria of OSAHS patients were (29.1 +/- 5.5) mm, (26.9 +/- 5.1) mm and (25.6 +/- 5.2) mm, respectively, and those of control adult were (23.0 +/- 3.8) mm, (22.6 +/- 2.7) mm and (21.5 +/- 2.6) mm, the depth of lingual arteria of OSAHS was more than that of control adults (t test, P0.05 or P0.01). The main factors affects lingual arterial depth were body mass index (BMI), lingual length and lingual thickness, unstandardized regression coefficient were 0.255, 0.11 and 0.03, respectively (analysis of variance, F = 6.216, P0.05). No damage of lingual arteria and nerve in 23 patients who had expanded glossectomy.The study showed statistical difference significance of lingual arterial CTA measurements between OSAHS patients and control adults. Guided with lingual arteria CTA data, the expanded glossectomy in OSAHS patients has proved good safety and high cure rate.

In this paper, we focus on current–voltage (I–V) characteristics in several kinds of quasi-one-dimensional (quasi-1D) nanofibers to investigate their electronic transport properties covering a wide temperature range from 300 down to 2 K. Since the complex structures composed of ordered conductive regions in series with disordered barriers in conducting polymer nanotubes/wires and CdS nanowires, all measured nonlinearI–V characteristics show temperature and field-dependent features and are well fitted to the extended fluctuation-induced tunneling and thermal excitation model (Kaiser expression). However, we find that there are surprisingly similar deviations emerged between theI–V data and fitting curves at the low bias voltages and low temperatures, which can be possibly ascribed to the electron–electron interaction in such quasi-1D systems with inhomogeneous nanostructures.

To obtain allelic loss mapping and define the minimal lost region on chromosome 1q21 in gastric carcinomas, and explore role of 1q21 loss of heterozygosity (LOH) in the development and progression of gastric carcinogenesis.Using 7 high-density microsatellite markers and PCR method, lq21 LOH was analyzed in 30 paired specimens of fresh gastric carcinoma, and the relation between 1q21 LOH and the clinicopathological features of the malignancy was tested.The LOH frequency on chromosome 1q21 from these gastric carcinoma tissues reached 60% (18/30). The LOH frequencies of the microsatellite markers D1S514, D1S2696, D1S498, D1S305, D1S2624, D1S2635 and D1S2702 were 13.3%, 10%, 20%, 23.3%, 33.3%, 40% and 23.3%, respectively. The minimal lost region on 1q21 LOH in the gastric carcinoma tissues was located in the region between D1S2624 and D1S2707, in the vicinity of D1S2635. No significant relations of 1q21 LOH to the patients' age, gender, location of the primary foci, clinical staging, or the tumor differentiation were noted (P0.05), but 1q21 LOH was correlated to lymph node metastases of the malignancy (P0.05).Higher frequency of 1q21 LOH occurs in gastric carcinoma cells, suggesting the presence of potential tumor suppressor genes closely associated with gastric carcinogenesis near the region of D1S2635.

To construct hu-PBL/SCID chimeras and to investigate the development of lymphoma and oncogenicity of the Epstein-Barr virus (EBV).Human peripheral blood lymphocytes (PBLs) were isolated from healthy adult donors and transplanted intraperitoneally into severe combined immunodeficient (SCID) mice. Mice with hu-PBL engraftment from healthy EBV seronegative donors were injected intraperitoneally with EBV-containing supernatant from suspension culture of B95-8 cell line (active infection), whereas mice receiving lymphocytes from healthy EBV seropositive donors were not re-infected with B95-8 derived EBV (latent infection). Pathological examination and molecular analysis were performed on experimental animals and induced neoplasms.In the early stage of this experiment, 12 mice died of acute graft-versus-host disease, mortality was 34.3% (12/35 mice) with an average life span of 17.5 days. In 19 survival hu-PBL/SCID chimeric recipients from 12 healthy donors, tumor incidence was 84.2% (16/19 mice). The average survival time of tumor-bearing mice was 65.5 days. EBV-related neoplasms in SCID mice were nodular tumors with aggressive and fatal features. Histological morphology of tumors exhibited diffuse large cell lymphomas. Immunohistochemistry revealed that LCA (CD45) and L26 (CD20) were positive, but both PS1 (CD3) and UCHL-1 (CD45RO) were negative, and EBV products ZEBRA, LMP1, and EBNA2 were expressed in a small number of tumor cells. EB virus particles were seen in the nuclei of some tumor cells by electron microscopy, and EBV DNA could be amplified in the tumor tissues by PCR. In situ hybridization indicated that the nuclei of tumor cells contained human-specific Alu sequence.EBV-induced tumors were human B-cell malignant lymphomas. We obtained direct causative evidence dealing with EBV-associated tumor deriving from normal human cells.

RNA interference (RNAi) technique is now widely used in studies of gene function, signal transduction pathway, and gene therapy because it can effectively and specifically inhibit gene expression. This study was designed to synthesize small interfering RNA (siRNA) by in vitro transcription, and construct retrovirus vectors to express small hairpin RNA (shRNA), detect RNAi in nasopharyngeal carcinoma cell lines, and to develop a RNAi technique platform.siRNAs targeting green fluorescent protein (GFP) and luciferase (Luc) were synthesized by in vitro transcription, while shRNAs targeting GFP and Luc were constructed from pSUPER.retro. Cervical cancer cell line HeLa, nasopharyngeal carcinoma cell lines CNE1, CNE2, and 5-8F were co-transfected with siRNAs or shRNAs and reporter gene pEGFP-N1 or pGL3. The expression of GFP was detected by fluorescent microscopy and Western blot. The activity of luciferase was measured by Luciferase Enzyme Assay System.siRNA duplexes with 3' UU overhangs and shRNA specifically silenced GFP expression, while antisense RNA and siRNA without 3' UU overhangs did not trigger RNA interference of GFP. Quantitative luciferase activity analysis showed that siRNA inhibited Luc expression in HeLa, CNE1, CNE2, and 5-8F cell lines with inhibition rates of 91.43%, 78.01%, 90.30%, and 62.85%, respectively. Similarly, the inhibition rate was 78.22% when shRNA targeting Luc was co-transfected into HeLa cell line.Both siRNAs and shRNAs can induce RNAi. 3' UU overhangs of siRNA may play a role in RNAi. RNAi can be triggered in both nasopharyngeal carcinoma cell lines and HeLa cell line.

Human embryonic stem (hES) cells have the capability of unlimited undifferentiated proliferation, yet maintain the potential to form perhaps any cell type in the body. Based on the high efficiency of the Epstein-Barr virus-based episomal vector in introducing exogenous genes of interest into mammalian cells, we applied this system to hES cells, expecting that this would resolve the problem of poor transfection efficiency existing in current hES cell research. Therefore, the first step was to establish EBNA1-positive hES cells. Using the Fugene 6 transfection reagent, we transfected hES cells with the EBNA1 expression vector and subsequently generated hES cell clones that stably expressed EBNA1 under drug selection. These clones were confirmed to express EBNA1 mRNA by RT-PCR and to express EBNA1 protein by Western blotting. Furthermore, luciferase reporter gene analysis was performed on the EBNA1 clones and revealed that the expressed EBNA1 protein was functional. When the EBNA1-positive cells were injected into severe combined immunodeficient (SCID) mice, they formed teratoma tissues containing all three embryonic germ layers and EBNA1 protein was detected in these teratoma tissues by Western blotting. All the results show that we have successfully created stable EBNA1-hES cells, thus laying a good foundation for further research.

To construct tree models for nasopharyngeal carcinoma (NPC)and explore the oncogenesis process of NPC.Based on the software which Desper et al developed, tree models were constructed for colorectal carcinoma (CC) from the comparative genomic hybridization (CGH) data of 118 CC patients and for NPC from the CGH data of 140 southern Chinese patients, respectively.Tree models for CC suggested that changes in -18q and +20q were important early events in colorectal carcinogenesis. As changes in -18q occurred prior to those in -17p, there might be some cause-effect relationship. Tree models for NPC suggested that change in -3p was an important early event in nasopharyngeal carcinogenesis, and those in -11q, -14q, -16q, -9p were also non-random genetic events in carcinogenesis, suggesting that there might be tumor-associated genes existing on these chromosome arms. The tree model also suggested the existence of oncogene on the short arm of chromosome 12.Constructing tree models based on the CGH data to demonstrate the initiation and progression of NPC might help elucidate its multigene, multistep and multipathway development. It may provide valuable clues to explore the mechanism of tumorigenesis.

To identify molecular features of neoplasms associated with EB virus, human peripheral blood lymphocytes (huPBL) were isolated from healthy volunteer donors and were transplanted intraperitoneally into SCID mice, and then huPBL/SCID mice were infected with EB virus. Serum levels of human IgG were measured by unidirectional immunodiffusion assay. Human Alu sequence and EBER-1 in tumor tissues were detected with PCR and in situ hybridization. Immunohistochemical staining was used to examine leukocyte differentiation antigens (LCA, L26, UCHL1, PS1), viral gene products (LMP1, EBNA2, BZLF1) and cellular oncoproteins (p53, C-myc, Bcl-2 and Bax). The experiments showed that tumors developed in 24 of 34 surviving huPBL/SCID mice by EBV infection. Histopathological and immunohistochemical observations demonstrated that all of the induced tumors in SCID mice were malignant lymphomas derived from human B-lymphocytes. In situ hybridization showed that tumor cells had EBV-encoded small RNA-1 (i.e. EBER-1). Alu sequence could be amplified by PCR from human genome of tumor tissues. Immunohistochemistry detected positive staining of BZLF1-encoded protein in a small population of tumor cells of almost all cases, and positive staining of LMP1 and EBNA2 only in small number of tumor cells. Human IgG could be found in the serum of 12 SCID mice on the 15th day after huPBL engraftment, and then increased with time and with the development of induced tumors in 6 mice. Positive rates of p53, C-myc, Bcl-2 and Bax expression were 83.33%, 100%, 95.83%, 91.67%, respectively, in 24 cases of the EBV-induced lymphomas. The results indicate that molecular lesions associated with the induced B-cell lymphoma involved EBV infection, expression of oncogenic viral genes, and abnormal expression of cellular oncogenes in human xenografts. Human IgG level in the serum of huPBL/SCID mice can be considered as a useful index for tumor development.

We previously constructed human peripheral blood lymphocyte (hu-PBL)/severe combined immunodeficiency mouse (SCID) chimeras and induced human B-cell lymphomas associated with Epstein-Barr virus (EBV) in SCID mice. However, a number of SCID mice died of graft-versus-host disease (GVHD) during the early experimental course. The aim of this study was to test the efficacy of cyclosporine A (CSA) for prevention of GVHD and to define how CSA inhibits the occurrence of GVHD and the production of soluble interleukin (IL) 2 receptor (sIL-2R) in hu-PBL/SCID mice. No mouse died in the active EBV infection group with CSA administration, while 17 mice in three groups without CSA administration died of GVHD. Mortalities in these three groups were 55.56% (5/9), 30.43% (7/23), and 27.78% (5/18), and the medium life span was 17 days. Over the first 33 days after hu-PBL transplantation, serum level of human sIL-2R in hu-PBL/SCID chimeras was stable in the active EBV infection plus CSA group, while sIL-2R concentration gradually increased in the sera of mice with active EBV infection without CSA administration and peaked at 22 days. Thirty-two mice developed tumors among the 43 surviving SCID mice. There was no significant difference of tumor incidence between the active EBV infection groups with CSA and without CSA administration (P > 0.05). From their morphological and immunohistochemical features, as well as detection of human Alu-sequence and EBV in tumor cells, these EBV-induced tumors were identified as human B-cell lymphomas. Thus, CSA can strikingly inhibit GVHD in hu-PBL/SCID chimeras, and should therefore be effective to establish a stable SCID mouse model of human lymphoma associated with EBV. Treatment with CSA had no effect on the tumor incidence in hu-PBL/SCID chimeras after active EBV infection. Accordingly, serum level of sIL-2R is a valuable indicator of GVHD occurrence in hu-PBL/SCID chimeras.

We examined the promoter hypermethylation of tumor-suppressor genes RASSF1A and TSLC1, quantitated EBV DNA load in nasopharyngeal carcinoma (NPC) tissues (T tissues), and matched tumor-adjacent tissues outside 0.5 cm (P tissues) and outside 1.0 cm (Z tissues) to evaluate the role of promoter hypermethylation of RASSF1A and TSLC1 as well as viral load in the pathogenesis of NPC. Methylation-specific polymerase chain reaction (PCR) for RASSF1A and TSLC1 and quantitative real-time PCR analysis of EBV DNA were performed on matched T, P, and Z tissues (n = 28) as well as chronic nasopharyngitis tissues (n = 8). Hypermethylated RASSF1A was frequently detected in the T (82%) and P tissues (75%), but less frequently in Z tissues (46%). he average quantities of EBV DNA (copies/microg DNA) in matched T, P, and Z tissues were 673,000, 90,000, and 7000. The differences of promoter hypermethylation of RASSF1A and EBV viral load among T, P, and Z tissues were statistically significant, with more frequent methylation and higher viral load detected when tissues examined were nearer to the NPC tissues. Our results suggest that aberrant hypermethylation of RASSF1A and high EBV load might be important events in NPC pathogenesis, and they may be useful molecular diagnostic markers for this cancer.