Acquired Immunodeficiency Syndrome ; complications ; pathology ; Antigens, CD34 ; metabolism ; Gastrectomy ; methods ; Humans ; Male ; Middle Aged ; Sarcoma, Kaposi ; metabolism ; pathology ; surgery ; virology ; Stomach ; pathology ; Stomach Neoplasms ; metabolism ; pathology ; surgery ; virology ; Vimentin ; metabolism

BACKGROUND AND OBJECTIVEEBV BamHI fragment H rightward open reading frame 1 (BHRF1), the Epstein-Barr virus (EBV) early gene, is structurally and functionally homologous to the oncogene bcl-2 and may play an important role in the development of EBV-associated tumors. To characterize the polymorphisms of BHRF1 in EBV-associated tumors, we analyzed the sequences of BHRF1 in isolates from nasopharyngeal carcinoma (NPC) and EBV-associated gastric carcinoma (EBVaGC) biopsies as well as throat washing (TW) samples from healthy donors.

METHODSBHRF1 DNA sequences were analyzed by polymerase chain reaction (PCR) and sequencing for 39 NPC samples, 40 EBVaGC samples, and 53 EBV-positive TW samples from healthy donors. The variants of BHRF1 gene were classified according to the signature changes. The EBV types 1 and 2 at nuclear antigen (EBNA) 3C locus were determined by PCR.

RESULTSCompared with EBV standard cell line B95-8, all isolates carried a silent mutation at amino acid (AA) 80 (nucleotide 54616 T→C), the AA88 L→V mutation was found in most isolates, and the AA79 V→L mutation in a few isolates. Other mutations were sporadically distributed. Based on the mutations at AA88 and AA79, 3 distinct variants of BHRF1 genes, designated as 79V88V, 79L88L, and 79V88L, were identified. The 79V88V was the most common variant. The distribution of the BHRF1 variants among the NPC, EBVaGC, and TW samples was not significant. The corresponding regions of bcl-2 homologues were conserved in all isolates except for 3 samples. The distribution of BHRF1 variants in type 1 and type 2 strains was significant different (P < 0.001, contingency coefficient was 0.554).

CONCLUSIONSThe 79V88V is the dominant variant in NPC, EBVaGC, and TW samples from healthy donors and preferential linkages between BHRF1 and EBNA3C variants exist. Conserved BHRF1 in Bcl-2 homologous domains is helpful to remain the important role of BHRF1.

Carcinoma ; Herpesvirus 4, Human ; genetics ; Humans ; Nasopharyngeal Neoplasms ; genetics ; metabolism ; virology ; Polymorphism, Genetic ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Sequence Analysis, DNA ; Stomach Neoplasms ; genetics ; metabolism ; virology ; Viral Proteins ; genetics ; metabolism

BACKGROUND: Epstein-Barr virus (EBV) is associated with various lymphoproliferative disorders and nasopharyngeal carcinoma. Recently, some gastric cancer cells were observed to contain the EBV sequence. We detected EBV in gastric cancer by using PCR to determine the frequency of EBV-associated gastric cancer, and performed immunohistochemical staining for the latent membrane protein (LMP1), p53 and CD44 to investigate the possible mechanism in EBV-associated gastric cancer. METHODS: Eighty-seven formalin-fixed and paraffin-embedded blocks (40 gastric adenocarcinomas, 34 adjacent normal tissues, 13 metastatic lymph nodes) from 40 surgically resected gastric specimens were studied. All patients were diagnosed with gastric cancer at the Kang-Nam St. Mary's Hospital between April 1995 and April 1997. After DNA was extracted from each paraffin block, we performed PCR and immunohistochemical staining for the LMP1, p53 and CD44. RESULTS: EBV was detected in 4 of 40 cases (10%). In 1 of 4 EBV-positive cases, EBV was also detected in a metastatic lymph node. The immunohistochemical staining for the LMP1, p53 and CD44 were negative in all the EBV-positive cancer patients. Of the patients having these cancers, 2 had a poorly differentiated adenocarcinoma with a lymphoepithelioma-like morphology. DISCUSSION: The frequency of EBV-associated gastric cancer is about 10% in Korea. Considering the negative result of the immunohistochemical staining for the LMP1, p53 and CD44, EBV-associated gastric cancer seems to have a different mechanism of tumorigenesis from ordinary gastric cancer or other EBV-associated cancers. This specific mechanism must be determined by further large scale studies.
Adenocarcinoma/metabolism/*virology ; Adult ; Antigens, CD44/metabolism ; Female ; Herpesvirus 4, Human/*isolation & purification ; Human ; Immunohistochemistry ; Male ; Middle Aged ; Polymerase Chain Reaction ; Protein p53/metabolism ; Stomach Neoplasms/metabolism/*virology ; Viral Matrix Proteins/metabolism

BACKGROUNDTo study the difference in gene expression between the EBV associated gastric carcinoma (EBVaGC) tissues. To explore the mechanism of gastric carcinoma pathogenesis initiated by EBV.

METHODSIn situ hybridization was used to study the frequencies of EBV small RNA expression in 155 cases of gastric carcinoma tissues. The expression levels of P53 protein and P21WAF1 protein were detected by immunohistochemistry in all gastric carcinoma tissues.

RESULTSThe expression of EBV small RNA was positive in 10 out of 155 cases (6.45%). The expression of P53 protein was weakly positive in 4 of the 10 cases. The expression level of P53 protein in EBVaGC was much lower than that in EBVnGC and was weakly positive in 30 of 145 cases with EBVnGC). P21WAF1 expression was detected in 7 of 10 cases with EBVaGC, but in 55 out of 145 cases with EBVaGC, P21WAF1 expression in EBVaGC was much higher than that in EBVnGC.

CONCLUSIONThere seems existing a special mechanism of pathogenesis in EBVaGC. In which P53 gene mutation may not play an important role.

Epstein-Barr Virus Infections ; metabolism ; pathology ; virology ; Herpesvirus 4, Human ; genetics ; physiology ; Host-Pathogen Interactions ; Humans ; Immunohistochemistry ; In Situ Hybridization ; Proto-Oncogene Proteins c-met ; metabolism ; RNA, Viral ; genetics ; Stomach Neoplasms ; metabolism ; pathology ; virology ; Tumor Suppressor Protein p53 ; metabolism

OBJECTIVES: Research on how the risk of gastric cancer increases with Epstein-Barr virus (EBV) infection is lacking. In a systematic review that investigated studies published until September 2014, the authors did not calculate the summary odds ratio (SOR) due to heterogeneity across studies. Therefore, we include here additional studies published until October 2015 and conduct a meta-analysis with meta-regression that controls for the heterogeneity among studies. METHODS: Using the studies selected in the previously published systematic review, we formulated lists of references, cited articles, and related articles provided by PubMed. From the lists, only case-control studies that detected EBV in tissue samples were selected. In order to control for the heterogeneity among studies, subgroup analysis and meta-regression were performed. RESULTS: In the 33 case-control results with adjacent non-cancer tissue, the total number of test samples in the case and control groups was 5280 and 4962, respectively. In the 14 case-control results with normal tissue, the total number of test samples in case and control groups was 1393 and 945, respectively. Upon meta-regression, the type of control tissue was found to be a statistically significant variable with regard to heterogeneity. When the control tissue was normal tissue of healthy individuals, the SOR was 3.41 (95% CI, 1.78 to 6.51; I-squared, 65.5%). CONCLUSIONS: The results of the present study support the argument that EBV infection increases the risk of gastric cancer. In the future, age-matched and sex-matched case-control studies should be conducted.
Case-Control Studies ; DNA, Viral/analysis/metabolism ; Databases, Factual ; Epstein-Barr Virus Infections/*pathology/virology ; Herpesvirus 4, Human/genetics/isolation & purification/*pathogenicity ; Humans ; Odds Ratio ; Stomach Neoplasms/*pathology/virology

OBJECTIVETo evaluate the H. pylori and Epstein-Barr virus infection in cardiac and distal gastric adenocarcinoma tissues in residents in Cixian county, a high risk area of esophageal cancer in Hebei province, and to explore the putative role of H. pylori and Epstein-Barr virus infection in the carcinogenesis of adenocarcinoma at different subsites of stomach.

METHODSH. pylori and Epstein-Barr virus latent membrane protein 1 (EBV-LMP1) immunopositivities were determined by Elivision(TM) plus immunohistochemical staining in 190 gastric adenocarcinoma tissues including 144 cases of cardiac adenocarcinoma and 46 cases of distal gastric adenocarcinoma. The relationship between H. pylori and Epstein-Barr virus infection and the subsite, Laurén type as well as other clinicopathological features of gastric adenocarcinoma were analyzed.

RESULTSNo significant difference was found between the H. pylori detection rates in cardiac and distal gastric adenocarcinomas(56.9% vs. 65.2%, P > 0.05). The detection rate of H. pylori in intestinal type was significantly higher than that in the diffuse type distal gastric adenocarcinomas (71.8% vs. 28.6%, P < 0.05). No positive expression of EBV-LMP1 was found in the gastric adenocarcinomas in this study.

CONCLUSIONSNo significant differences in H. pylori and EBV-LMP1 infections were found between cardiac and distal gastric adenocarcinomas in Cixian county. H. pylori infection is related with the intestinal type of distal gastric adenocarcinoma.

Adenocarcinoma ; microbiology ; pathology ; virology ; Aged ; Cardia ; China ; Epstein-Barr Virus Infections ; pathology ; Female ; Helicobacter Infections ; pathology ; Helicobacter pylori ; isolation & purification ; Humans ; Male ; Middle Aged ; Stomach Neoplasms ; microbiology ; pathology ; virology ; Viral Matrix Proteins ; metabolism

Activated beta-catenin is suggested to inhibit NF-kappaB activation, and we previously demonstrated that NF-kappaB nuclear positivity was more frequent in Epstein-Barr virus (EBV)-infected gastric carcinomas. It is controversial that beta-catenin and E-cadherin are prognostic markers in gastric carcinomas. To define a relationship between beta-catenin and EBV, and the prognostic value of beta-catenin and E-cadherin, we analyzed in situ hybridization for EBV-encoded small RNAs, betacatenin, and E-cadherin immunohistochemistry, and clinicophatological features in 111 gastric carcinomas. EBV infection was detected in seven carcinomas (6.3%); none of seven showed beta-catenin nuclear accumulation, and five out of seven revealed beta-catenin membranous loss or cytoplamic expression. Eighty cases (72.1%) showed beta-catenin alteration; i.e., loss of membrane staining in 65 (58.6 %), cytoplasmic expression in 35 (31.5%), and nuclear accumulation in 15 (13.5%). E-cadherin alteration was observed in 34 cases (30.6%) and correlated with betacatenin alteration. On multivariate analysis, the combined immunoexpression group of beta-catenin nuclear accumulation/ E-cadherin alteration and the advanced TNM cancer stage group showed poor patient's survival (p<0.05). In conclusion, betacatenin activation through nuclear accumulation hardly occurred in EBV-infected gastric carcinomas. The combined immunoexpression pattern of beta-catenin and E-cadherin can be used as a prognostic marker in gastric carcinomas.
Adult ; Aged ; Cadherins/*metabolism ; Carcinoma/*metabolism/*virology ; Cell Nucleus/metabolism ; Female ; *Gene Expression Regulation, Neoplastic ; *Gene Expression Regulation, Viral ; Herpesvirus 4, Human/*metabolism ; Humans ; Immunohistochemistry/methods ; In Situ Hybridization ; Male ; Middle Aged ; NF-kappa B/metabolism ; Prognosis ; Stomach Neoplasms/*metabolism/*virology ; beta Catenin/*metabolism

OBJECTIVETo investigate the prevalence of Epstein-Barr virus (EBV)-associated gastric carcinomas in Guangzhou, their clinicopathologic features and related protein expressions including DNMT1, p16, and cyclin D1.

METHODA total of 676 cases of EBV-associated gastric carcinoma were included in the study. The presence of EBV-encoded small RNA1 (EBER1), a marker for EBV infection, was analyzed by in-situ hybridization using formalin-fixed and paraffin-embedded tumor samples. Expression of EBV-encoded proteins, DNMT1, p16 and cyclin D1 were detected by immunohistochemistry.

RESULTSForty-five of 676 gastric carcinomas showed EBER intranuclear positivity in all tumor cells. EBV involvement was significantly more frequent among the male than the female patients, especially in tumors of less differentiated types (diffuse type) and involving the upper stomach (P < 0.05). EBNA1 and LMP2A expression were detected in 42 (93.3%) and 24 (53.3%) cases, respectively. None expressed EBNA2, LMP1, and ZEBRA. Among 45 cases of EBV associated gastric carcinomas, DNMT1, p16 and cyclin D1 expression were seen in 35 (77.8%), 10 (22.2%), and 29 (64.4%) cases, respectively. In contrast, among 40 EBV negative gastric carcinomas, expression of the three proteins were 20 (50.0%), 25 (62.5%) and 12 (30.0%), respectively. The difference of expression of the three proteins between the two groups was significant (P < 0.05). Expression of p16 correlated with the depth of the tumor invasion. Correlated protein expression was seen between LMP2A and DNMT1, between DNMT1 and p16, and between p16 and cyclin D1 (P < 0.05).

CONCLUSIONSEBV associated gastric carcinoma accounts for 6.7% of gastric carcinomas in Guangzhou with the Latency I pattern in some cases and between Latency I and II in others. The correlated expression of LMP2A, DNMT1, p16 and cyclin D1 may contribute to the pathogenesis of EBV associated gastric carcinomas.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; China ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; DNA (Cytosine-5-)-Methyltransferase 1 ; DNA (Cytosine-5-)-Methyltransferases ; metabolism ; Epstein-Barr Virus Infections ; virology ; Epstein-Barr Virus Nuclear Antigens ; metabolism ; Female ; Herpesvirus 4, Human ; isolation & purification ; Humans ; Male ; Middle Aged ; Neoplasm Invasiveness ; RNA, Viral ; metabolism ; Sex Factors ; Stomach Neoplasms ; metabolism ; pathology ; virology ; Viral Matrix Proteins ; metabolism ; Young Adult

OBJECTIVETo study the regulatory effect of Helicobacter pylori CagA protein on gastrin promoter and the related signaling pathways as to further elucidate the mechanism of the development and progression of human gastric carcinoma.

METHODSAfter pcDNA3.1ZEO(-)/CagAand PGL/GP were identified by double restriction enzyme digestion, PCR and sequencing, the gastric cancer cell lines AGS and SGC-7901 cells were co-transfected with pcDNA3.1ZEO(-)/CagA and PGL/GP for 48 h. Alternatively, AGS and SGC-7901 cells were transfected by PGL/GP for 36 h later, and infected with Helicobacter pylori for additional 12 h. Meanwhile, the transfected and infected cells were treated using the JAK2 signaling pathway inhibitor AG490 and the ERK signaling pathway inhibitor U0126. The untreated cells and empty-vector-transfected cells were used as the control. Finally, luciferase activity was detected using the luciferase reporter assay system in transfected and infected cells. The levels of gastrin mRNA was determined by TaqMan® real-time quantitative PCR.

RESULTSAfter co-transfection with pcDNA3.1ZEO(-)/CagA and PGL/GP, the activities of luciferase were increased by 251.3, 106.1 and 2.4 times in AGS cells and 35.8, 22.7 and 13.4 times in SGC-7901 cells, respectively, as compared with that of the control, pcDNA3.1 ZEO(-)/CagA + PGL3/Basic and pcDNA3.1 ZEO(-) + PGL/GP groups. The activities of luciferase in PGL/GP transfection and HP infection group were also increased by 1673.2, 33.5, 1.4 times in AGS cells and 1180.2, 72.2 and 1.5 times in SGC-7901 cells, respectively, as compared with that of the control, PGL3/Basic + HP and PGL/GP groups. There were statistically significant differences between them (P < 0.05), which suggested that the transcription activity of gastrin promoter increased significantly. But after adding the inhibitor AG490 and U0126, respectively, the activities of luciferase were significantly decreased by 95.7% (U0126) and 33.0% (AG490) in co-transfected AGS cells and 94.8% (U0126) and 86.2% (AG490) in co-transfected SGC-7901 cells with pcDNA3.1ZEO(-)/CagA and PGL/GP (P < 0.05). In the PGL/GP transfection and HP infection group, the activities of luciferase were significantly decreased by 24.6% (U0126) and 25.8% (AG490) in AGS cells and 57.3% (U0126) and 14.1% (AG490) after adding the inhibitor AG490 and U0126, respectively (P < 0.05). The results showed that the gastrin promoter activities were significantly inhibited. The gastrin mRNA levels were 3.0 and 4.5 times higher in HP-infected AGS and SGC-7901 cells, respectively, than that in the control groups. In the cells transfected with pcDNA3.1ZEO(-)/CagA, the gastrin mRNA levels were raised 10.8 and 2.3 times (AGS cells) and 10.9 and 16.2 times (SGC-7901 cells), respectively, as compared with that of control and pcDNA3.1ZEO(-) groups. All of the differences were statistically significant (P < 0.05).

CONCLUSIONThese results suggest that CagA may activate the gastrin promoter and up-regulate the expression of gastrin gene, and CagA is one of the important proteins in regulating gastrin gene expression. The ERK/MAPK and JAK/STAT signaling pathways may be involved in the controlling of gastrin gene expression by CagA.

Antigens, Bacterial ; genetics ; metabolism ; Antineoplastic Agents ; pharmacology ; Bacterial Proteins ; genetics ; metabolism ; Butadienes ; pharmacology ; Cell Line, Tumor ; Enzyme Inhibitors ; pharmacology ; Gastrins ; biosynthesis ; genetics ; Gene Expression Regulation, Neoplastic ; Genetic Vectors ; Helicobacter Infections ; Helicobacter pylori ; isolation & purification ; Humans ; Nitriles ; pharmacology ; Promoter Regions, Genetic ; RNA, Messenger ; metabolism ; Stomach Neoplasms ; metabolism ; pathology ; virology ; Transfection ; Tyrphostins ; pharmacology ; Up-Regulation

BACKGROUND AND OBJECTIVEEpstein-Barr virus (EBV) has been detected in about 10% of gastric carcinomas. However, the pathogenetic role of EBV in gastric carcinoma is uncertain. This study was to explore the correlation of Fas/FasL expression to the apoptosis of tumor cells and tumor-infiltrating lymphocytes (TIL) in EBV-associated gastric carcinoma (EBVaGC).

METHODSFas/FasL expression in 49 specimens of EBVaGC, 20 specimens of EBV-negative gastric carcinoma (EBVnGC) and 12 specimens of normal gastric mucosa was detected by immunohistochemistry. The apoptotic index (AI) of cells was determined by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL).

RESULTSThe positive rates of Fas were 91.7% in normal gastric mucosa and 76.8% in gastric carcinoma (P < 0.05); those of FasL were 16.7% in normal gastric mucosa and 58% in gastric carcinoma (P < 0.05). The positive rate of Fas was significantly lower in EBVaGC than in EBVnGC (71.4% vs. 90.0%, P < 0.05). The positive rate of FasL in EBVaGC was significantly higher than that in EBVnGC (63.2% vs. 45%, P < 0.05). The AI of EBVaGC cells was significantly lower than that of EBVnGC cells (P = 0.002). The number and AI of TIL in EBVaGC were higher than those in EBVnGC (P < 0.05). The AI of TIL was positively correlated with the level of FasL expression in tumor cells (r=0.237, P = 0.028).

CONCLUSIONUp-regulation of FasL expression and decrease of TIL apoptosis in EBVaGC may facilitate the escape of tumor cells from the host immunosurveillance, and it might contribute to the development and progression of carcinoma.

Adult ; Apoptosis ; Epstein-Barr Virus Infections ; Fas Ligand Protein ; metabolism ; Female ; Herpesvirus 4, Human ; isolation & purification ; Humans ; Immunohistochemistry ; Immunologic Surveillance ; In Situ Nick-End Labeling ; Lymphocytes, Tumor-Infiltrating ; pathology ; Male ; Middle Aged ; Stomach Neoplasms ; metabolism ; pathology ; virology ; Tumor Escape ; fas Receptor ; metabolism