Epstein-Barr virus-associated gastric carcinoma: Evidence of age-dependence among a Mexican population

AIM： To investigate features of Epstein-Barr virus （EBV）associated gastric carcinoma （EBVaGC） among a Mexican population. METHODS： Cases of primary gastric adenocarcinoma were retrieved from the files of the Departments of Pathology at the Instituto Nacional de Cancerologia and the Instituto Nacional de la Nutrición in Mexico City. The anatomic site of the gastric neoplasia was identified, and carcinomas were histologically classified as intestinal and diffuse types and subclassified as proposed by the Japanese Research Society for Gastric Cancer. EBV-encoded small non-polyadenylated RNA-1 （EBER-1） in situ hybridization was conducted to determine the presence of EBV in neoplastic cells. RESULTS： We studied 330 consecutive, non-selected, primary gastric carcinomas. Among these, there were 173 male and 157 female patients （male/female ratio 1.1/1）. EBER-1 was detected in 24 （7.3%） cases （male/ female ratio： 1.2/1）. The mean age for the entire group was 58.1 years （range： 20-88 years）, whereas the mean age for patients harboring EBER-1-positive gastric carcinomas was 65.3 years （range： 50-84 years）. Age and histological type showed statistically significant differences, when EBER-1-positive and -negative gastric carcinomas were compared. EBER-1 was detected in hyperplastic- and dysplastic-gastric mucosa surrounding two EBER-1-negative carcinomas, respectively. CONCLUSION： Among Latin-American countries, Mexico has the lowest frequency of EBVaGC. Indeed, the Mexican population 〉50 years of age was selectively affected. Ethnic variations are responsible for the epidemiologic behavior of EBVaGC among the worldwide population.

Expression of Epstein-Barr virus genes in EBV-associated gastric carcinomas

AIM: To understand the expression of latent and lytic genes of Epstein-Barr virus (EBV) in EBV-associated gastric carcinoma (EBVaGC) and to explore the relationship between EBV-encoded genes and development of EBVaGC at molecular level, METHODS: One hundred and seventy-two gastric carcinoma tissues and 172 corresponding para-carcinoma tissues were tested for EBV genome by polymerase chain reaction (PCR)-Southern blotting. EBV-encoded small RNA (EBER) 1 of the PCR positive specimens was detected by in situ hybridization (ISH). Gastric carcinomas with positive EBER1 signals were classified as EBVaGCs. RT-PCR and Southern hybridization were applied to the detection of expression of nuclear antigen (EBNA) promoters (Qp, Wp and Cp), EBNA 1 and EBNA 2, latent membrane proteins (LMP) 1, 2A and 2B and lytic genes (immediate early genes BZLF1 and BRLF1, early genes BARF1 and BHRF1, late genes BcLF1 and BLLF1) in EBVaGCs. RESULTS: Eleven EBV positive samples existed in gastric carcinoma tissues (6.39%). No EBV positive sample was found in corresponding para-carcinoma tissues. The difference between EBV positivity in carcinoma tissues and corresponding para-carcinoma tissues was significant (x2 = 9.0909, P = 0.0026). Transcripts of Qp and EBNA1 were detected in all the 11 EBVaGCs, while both Wp and Cp were silent. EBNA2, LMP1 and LMP2B mRNA were absent in all the cases, while LMP2A mRNA was detected in 4 of the 11 cases. Of the 11 EBVaGCs, 7 exhibited BcLFl transcripts and 2 exhibited BHRF1 transcripts. The transcripts of BZLF1 and BARF1 were detected in 5 cases, respectively. No BLLF1 and BRLF mRNA were detected. CONCLUSION: The latent pattern of EBV in gastric carcinoma corresponds to the latency I/II. Some lytic infection genes are expressed in EBVaGCs tissues. BARF1 and BHRF1 genes may play an important role in tumorigenesis of gastric carcinoma.

Clinical and pathological characterization of epstein-barr virus-associated gastric carcinomas in portugal

AIM To determine the prevalence of epstein-barr virus(eb V)-associated gastric carcinomas in the North Region of Portugal and to study its clinicopathological characteristics. METHODS We have performed a retrospective study including a total of 179 consecutive patients with gastric cancer(GC) submitted to gastrectomy during 2011 at the Portuguese Oncology Institute of Porto. Clinical and pathological data was collected from individual clinical records and inserted on a database with unique codification. Tumour tissues were collected from the institutional tumour bank. eb V was detected by in situ hybridization for the detection of eb V-encoded small RNAs(ebe Rs) and eb V latent proteins(LMP1 and LMP2 A) were detected by immunohistochemistry.RESULTS The analysis showed that eb V-associated gastric carcinomas(eb Va GC) represents 8.4%(15/179) of all GC cases, with a significant differential distribution among histological types(P < 0.001): 100%(3/3) of medullary carcinomas, 100%(1/1) of adenosquamous carcinoma, 8.7%(8/92) of tubular adenocarcinomas, 8.0%(2/25) of mixed carcinomas and 2%(1/51) in poorly cohesive carcinomas. The analysis revealed a higher predominance of eb Va GC in the upper third and middle(cardia, fundus and body) of the stomach(P = 0.041), a significant lower number of regional lymph nodes invasion(P = 0.025) and a tendency for better prognosis(P = 0.222). eb V latent protein expression revealed that all eb Va GC cases were LMP1-negative, nevertheless 6 cases(40%) expressed LPM2 A, which reveals that these cases show a distinct eb V-Latency profile(latency II-like).CONCLUSION eb Va GC represents 8.4% of all GC in the North Region of Portugal. The eb V-infected patients have specific clinic-pathological features that should be further explored to develop new strategies of management and treatment.

Epigenetic dysregulation in Epstein-Barr virus-associated gastric carcinoma: Disease and treatments

Epstein-Barr virus(EBV)-associated gastric carcinoma(EBVaGC)comprises nearly 10%of gastric carcinoma cases worldwide.Recently,it was recognised to have unique clinicopathologic characteristics,including male predominance,lower rates of lymph node involvement,and better prognosis.EBVaGC is further characterised by abnormal hypermethylation of tumour suppressor gene promoter regions,causing down-regulation of their expression.In the present review,we critically discuss the role of EBV in gastric carcinogenesis,summarising the role of viral proteins and microRNAs with respect to aberrant methylation in EBVaGC.Given the role of epigenetic dysregulation in tumourigenesis,epigenetic modifiers may represent a novel therapeutic strategy.

Epstein-Barr virus-associated lymphoepithelioma-like early gastric carcinomas and endoscopic submucosal dissection: Case series

Epstein-Barr virus (EBV)-associated lymphoepithelioma-like gastric carcinoma (LELC) is characterized by a lower lymph node (LN) metastasis rate and a higher survival rate than other forms of gastric cancer. Although current prognosis for LELC is favorable, the most common approach is radical gastrectomy involving an extensive D2 lymph node dissection. Here, we report four cases of EBV-associated early LELC that were treated by an alternative approach, endoscopic submucosal dissection (ESD). The long-term outcome of this procedure is discussed. All patients were treated by ESD en bloc, and all ESD specimens showed tumor-free lateral resection margins. None of the lesions showed lymphovascular invasion. A pathological examination of ESD specimens revealed submucosal invasion of more than 500 &#x003bc;m in all four cases. One patient underwent additional radical surgery post-ESD; no residual tumor or LN metastasis was noted in the surgical specimen. The other three patients did not undergo additional surgery, either because of severe comorbidity or their refusal to undergo operation, but were subjected to medical follow-up. None of the ESD-treated patients reported local recurrence or distant metastases during the 27-32 mo of follow-up after ESD.

E-cadherin and beta-catenin expression in Epstein-Barr virus-associated gastric carcinoma and their prognostic significance

AIM： To examine the role of E-cadherin and betacatenin in carcinogenesis and to assess their prognostic implication in Epstein-Barr virus-associated gastric carcinomas （EBV-GCs）. METHODS： We compared the frequency of E-cadherin and beta-catenin expression in 59 EBV-GCs and 120 non-EBV-GCs, and examined the association between patients＇ prognosis and the expressions of these proteins. RESULTS： Neither the cellular-membranous nor the cytoplasmic E-cadherin expression showed any difference between EBV-GCs and non-EBV-GCs. On the other hand, loss of membranous expression of beta- catenin occurred more frequently in non-EBV-GCs than EBV-GCs [odds ratio = 0.41; 950 confidence interval （CI）, 0.19-0.90]. Furthermore, the nuclear and/or cytoplosmic expression of beta-catenin was seen more frequently in EBV-GCs than non-EBV-GCs （odds ratio = 2.23; 95% CI, 0.97-5.09）, and was observed in a larger proportion of carcinoma cells of EBV-GCs than non-EBV-GCs （P = 0.024）. Survival analysis for non-EBV-GC revealed that lymph node metastasis was significantly associated with poor prognosis （P 〈 0.001）. Among EBV- GCs, the depth of invasion （P = 0.005）, lymph node metastasis （P = 0.004） and an intestinal type by Lauren classification （hazard ratio = 9.47; 95% CI, 2.67-33.6） were significantly associated with poor prognosis. On the other hand, nuclear and/or cytoplasmic expression of beta-catenin was associated with a better prognosis in patients with EBV-GC （hazard ratio = 0.32; 95% CI, 0.11-0.93）. CONCLUSION： We observed more frequent preservation of beta-catenin in cell membrane and accumulation in nuclei and/or cytoplasm in EBV-GCs than in non-EBV- GCs. Factors involved in the prognosis of EBV-GCs and non-EBV-GCs are different in the two conditions.

Epstein-Barr virus-associated gastric carcinoma in Kazakhstan

AIM: To investigate the incidence of Epstein-Barr virus-associated gastric cancer (EBV-GC) in Kazakhstan and to compare it with that in Russia, Western and Asian countries in order to evaluate the significance of epidemiopathologic and ethnic factors. METHODS: In situ hybridization (ISH) of EBV-encoded small RNA-1 (EBER-1) was used to identify the presence of EBER-1 signal in 139 formalin-fixed and paraffin-embedded GC tissues from Kazakhstan. RESULTS: EBER-1 expression was observed in the nuclei of 10% of the cases of GC (14/139), but not in the surrounding normal mucosa. The incidence of the diffuse type of EBV-GC was significantly higher in Kazakhstan (14%, 13/91) than that of the intestinal type (2%, 1/48). Furthermore, the incidence was significantly higher in males (14%, 12/89) than in females (3.7%, 2/53) from all countries. The overall incidence of EBV-GC increased from 6.7% in Asian countries to 8.7% in Russia, 10.1% in Kazakhstan and 16% in Western countries. CONCLUSION: Geographical differences in the incidence of EBV-GC may reflect the epidemiologic factors and/or dietary habits independent of histological type and sex.

Epstein-Barr virus is associated with gastric carcinoma: The question is what is the significance?

AIM: To examine the possible role of the Epstein- Barr Virus (EBV) in the development of gastric adenocarcinoma (GC). It is unclear whether EBV is involved in GC development or is a consequence of gastric inflammation secondary to immunosuppressive treatments. METHODS: A systematic review was carried out of all published observational studies on the temporal association between EBV and GC, with a view to determine a causal relationship. RESULTS: The present study showed that the worldwide crude prevalence of EBV in gastric adenocarcinoma was 8.29%. The prevalence varied from 7.08% for intestinal type and 9.82% for diffuse type of GC. It was observed that Western and Central Asian countries had a significantly higher frequency of EBV positive cases compared to South-Eastern countries. America had the highest EBV-GC prevalence whereas Europe had the lowest. CONCLUSION: The present review has demonstrated a high prevalence of EBV in gastric adenocarcinoma. However, studies designed to assess a temporal relationship and histological association using sensitive techniques should be carried out to establish the role of EBV in GC carcinogenesis.

single nucleotide polymorphism in theEpstein-Barr virus genome is strongly associatedwith a high risk of nasopharyngeal carcinoma

Background Epstein-Barr virus （EBV） commonly infects the general population and has been associated withnasopharyngeal carcinoma （NPC）, which has a high incidence in certain regions.This study aimed to address how EBVvariations contribute to the risk of NPC.Methods： Using logistic regression analysis and based on the sequence variations at EBV-encoded RPMSh a multistageassociation study was conducted to identify EBV variations associated with NPC risk. A protein degradationassay was performed to characterize the functional relevance of the RPMS1 variations.Results： Based on EBV-encoded RPMS1 variations, a single nucleotide polymorphism （SNP） in the EBV genome（locus 155391： G〉A, named G155391 A） was associated with NPC in 157 cases and 319 healthy controls from an NPCendemic region in South China [P 〈 0.001, odds ratio （OR） = 4.47,95% confidence interval （Cl） 2.71-7.37].The resultswere further validated in three independent cohorts from the NPC endemic region （P 〈 0.001, OR = 5.20,95% Cl3.18-8.50 in 168 cases vs. 241 controls, and P 〈 0.001, OR = 5.27,95% Cl 4.06-6.85 in 726 cases vs. 880 controls） anda non-endemic region （P 〈 0.001, OR = 7.52,95% Cl 3.69-1532 in 58 cases vs. 612 controls）.The combined analysisin 1109 cases and 2052 controls revealed that the SNP G155391A was strongly associated with NPC （Pcomb/ned 〈 0.001,OR = 5.27,95% Cl 4.31-6.44）. Moreover, the frequency of the SNP G155391A was associated with NPC incidence butwas not associated with the incidences of other EBV-related malignancies. Furthermore, the protein degradation assayshowed that this SNP decreased the degradation of the oncogenic RPMS1 protein.Conclusions： Our study identified an EBV variation specifically and significantly associated with a high risk of NPCThese findings provide insights into the pathogenesis of NPC and strategies for prevention.

Gastric submucosa-invasive carcinoma associated with EpsteinBarr virus and endoscopic submucosal dissection: A case report

BACKGROUND Epstein-Barr virus(EBV)-associated carcinoma is a gastric cancer subtype with a morphology characterized by gastric carcinoma with lymphoid stroma(GCLS).Clinicopathological studies have indicated a better prognosis for GCLS than for common gastric carcinomas.Some previous cases of early gastric cancer associated with EBV had been diagnosed by endoscopic resection.CASE SUMMARY We present two GCLS cases subjected to endoscopic submucosal dissection(ESD)for a definitive diagnosis.A protruded gastric lesion was identified by routine endoscopic examination,but forceps biopsy showed no atypical cells before ESD.The resected specimen showed a poorly differentiated adenocarcinoma with lymphoid cells involving the mucosa and submucosa.The final diagnosis was submucosa-invasive poorly differentiated gastric adenocarcinoma.Accordingly,additional gastrectomy was recommended to obtain a complete cure.One patient underwent additional distal gastrectomy with lymph node dissection,but the other was refused because of cardiovascular complications.Both patients remained in remission for more than half a year.EBV positivity was determined by EBV-encoded RNA in situ hybridization.We also conducted a literature review of cases of early gastric cancer associated with EBV that had been diagnosed by ESD.CONCLUSION Submucosa-invasive GCLS could be dissected using ESD,and EBV positivity should be subsequently assessed to determine whether or not any additional curative surgery is required.Further prospective investigations on the prevalence of lymph node metastasis in EBV-associated carcinoma should be performed to expand the indications for endoscopic resection.

Correlation of Epstein-Barr virus and its encoded proteins with Helicobacter pylori and expression of c-met and c-myc in gastric carcinoma

AIM： To investigate the interrelationship of Epstein-Barr virus （EBV） and EBV- encoded proteins with Helicobacter pylori （H pylor/~ infection and the expression of c-met and c-myc oncogene proteins in gastric carcinoma, and to explore their role in gastric carcinogenesis. METHODS： One hundred and eighty-five gastric carcinoma tissues were detected by polymerase chain reaction （PCR）-Southern blot for EBV genome and in situ hybridization （ISH） for EBV-encoded small RNA 1 （EBER1）. Gastric carcinoma with positive EBER1 signals was confirmed EBV-associated gastric carcinoma （EBVaGC）. The status of Hpylori infection in 185 gastric carcinomas was assessed by rapid urease test and PCR. The samples with positive PCR and urease test were defined as H pylorl infection. The expression of c-met and c-myc oncogene proteins in tissues of EBVaGC and matched EBV-negative gastric carcinoma （EBVnGC） were examined by immunohistochemistry. RT-PCR and Southern hybridization were used to detect the expression of nuclear antigens （EBNAs） 1 and 2, latent membrane protein （LMP） 1, early genes BARF1 and BHRF1 in EBVaGC cases. RESULTS： The positive rate of H pylori and EBV in 185 gastric carcinomas was 59.45% （110/185） and 7.03% （13/185） respectively. No difference was found in sex, age, pathological differentiation, clinical stages and lymph node metastasis between H pylori-positive and H pylori-negative gastric carcinomas. However, the positive rate of H pylori infection in the antrum gastric carcinomas was higher than that of cardia and body gastric carcinomas. In our series, age, pathological differentiation, clinical stages, lymph node metastasis and location of cancer were not different between EBVnGC and EBVaGC, while the positive rate of EBV in male patients was significantly higher than that of female patients. The positivity of Hpylori in EBV-associated and EBV-negative gastric carcinomas was 46.15% （6/13） and 81.40%（104/172） respectively. There was no significant correlation between EBV and H pylori infection. The c-met overexpression was significantly higher in the EBVaGC group than in the EBVnGC group. However, c-met and c-myc expression did not show significant difference between the two groups. Transcripts of EBNA1 were detected in all 13 EBVaGCs, while both EBNA2 and LMP1 mRNA were not detected. Six of the 13 cases exhibited BARF1 transcripts and 2 exhibited BHRF1 transcripts. CONCLUSION： The positivity of H pylori in EBVnGCs is higher than that of EBVaGCs, but no significant correlation is found between EBV infection and H pylori infection. H pylori-positive gastric carcinoma is predominant in antrum location, while EBVaGC has a tendency of predominance in cardia/body location. EBV infection is associated with c-met abnormal expression but not with c-myc protein in EBVaGC. c-met overexpression is not induced by LMP1. BARF1 and BHRF1 may play important roles in the tumorigenesis of EBVaGC through different pathways.

Relationship between Epstein-Barr virus-encoded proteins with cell proliferation,apoptosis,and apoptosis-related proteins in gastric carcinoma

AIM: To investigate the interrelationship between Epstein-Barr virus (EBV)-encoded proteins and cell proliferation, apoptosis and apoptosis-related proteins in gastric carcinoma, and to explore their role in gastric carcinogenesis. METHODS: Tissues from 13 cases of EBV-associated gastric carcinoma (EBVaGC) and 45 cases of matched EBV-negative gastric carcinoma (EBVnGC) were collected, and then subjected to analysis for apoptotic index (AI) using the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end-labeling (TUNEL) assay. Nuclear cell proliferation-associated antigen ki-67 index (KI), bcl-2, and p53 expression were examined by immunohistochemistry.p53 mutation in exons 5-8 of 13 EBVaGC cases was determined by single-strand conformation polymorphism (SSCP) and DNA sequencing.RT-PCR and Southern hybridization were used to detect the expression of nuclear antigens (EBNAs) 1 and 2, latent membrane protein (IMP) 1, immediately early gene BZLF1 and early genes BARF1 and BHRF1 in 13 EBVaGC cases. RESULTS: The percentage of AI, KI and p53 overexpression was significantly lower in the EBVaGC group than in the EBVnGC group. However, bcl-2 expression did not show significant difference between the two groups. p53 gene mutations were not found in 13 EBVaGCs. Transcripts of EBNA1 were detected in all 13 EBVaGCs, while both EBNA2 and LMP1 mRNA were not detected. Six of the thirteen cases exhibited BZLF1 transcripts and two exhibited BHRF1 transcripts. BARF1 mRNA was detected in six cases. CONCLUSION: Lower AI and KI may reflect a low biological activity in EBVaGC. EBV infection is associated with p53 abnormal expression but not bcl-2 protein in EBVaGC. BZLF1,BARF1,and BHRF1 may play important roles in inhibiting cell apoptosis and tumorigenesis of EBVaGC through different pathways.

H pylori (CagA) and Epstein-Barr virus infection in gastric carcinomas:Correlation with p53 mutation and c-Myc,Bcl-2 and Bax expression

AIM: To investigate the interrelationship between H pylori and Epstein-Barr virus (EBV) infection in the gastric carcinogenesis having in focus the p53 mutation and the c-Myc, Bcl-2 and Bax expression. METHODS: seventy-one gastric carcinoma tissues were assessed by polymerase chain reaction (PCR) for H pylori and in situ hybridization for EBV. c-Myc, Bcl-2 and Bax expression were detected by immunohistochemistry and single-stranded conformational polymorphism (SSCP) for p53 mutation. RESULTS: The positivity rates for H pylori and EBV were 94.4% and 8.45%, respectively. The majority of the cases displayed only the H pylori presence. All EBV positive cases were also H pylori positive. None infectious agent was observed in 5.55% of the cases. The intestinal type tumor was more frequent in the co-infected and non-infected groups. The female predominated in the non-infected group showing statistical significance (70.4% vs 29.6%, P=0.039). The Bcl-2 was only detected in the group exclusively infected by H pylori. However, c-Myc and Bax were detected in the three groups but with a low frequency in the co-infected group. Mutation of p53 was present in all groups, with the highest frequencies in the H pylori positive groups. CONCLUSION: The frequency of H pylori infection in gastric carcinomas was high. The presented data indicated that gastric carcinogenesis has different pathways depending of the presence of the two investigated infectious agents, suggesting a possible involvement of H pylori with apoptotic process. The low expression of c-Myc and Bax in the EBV-positive groups suggests that EBV may inhibit the expression of these proteins. Nevertheless, p53 mutation shows to be a relevant alteration, independent of both infectious agents.

Association of single nucleotide polymorphism rs2065955 of the filaggrin gene with susceptibility to Epstein-Barr virus-associated gastric carcinoma and EBV-negative gastric carcinoma

The relationship between the Filaggrin gene(FLG) rs2065955 polymorphism and susceptibility to Epstein-Barr virus(EBV)-associated gastric carcinoma(EBVa GC) and EBV-negative gastric carcinoma(EBVn GC) was investigated in Shandong Province,China.We detected the FLG rs2065955 genotype and allele distribution by using PCR and restriction fragment length polymorphism(RFLP) in 64 EBVa GC,82 EBVn GC,and 111 normal control samples.Immunohistochemistry was used to detect the level of FLG protein in 35 EBVa GC and 51 EBVn GC tumor tissues.Compared with normal controls,the genotype CC and allele C of FLG rs2065955 showed higher frequency in EBVa GC and EBVn GC.There was no significant difference between EBVa GC and EBVn GC in allele distribution of FLG rs2065955,but the genotype CC was found more frequently in EBVa GC than in EBVn GC.The risk of developing either EBVa GC or EBVn GC in genotype CC was higher than in other genotypes.Furthermore,genotype CC of FLG rs2065955 may contribute more to the risk of developing EBVa GC than EBVn GC.There was no significant difference in the expression level of FLG protein between EBVa GC and EBVn GC.In conclusion,the FLG rs2065955 polymorphism was significantly related to gastric carcinoma.Allele C of FLG rs2065955 could be a risk factor for EBVa GC or EBVn GC,while genotype CC of FLG rs2065955 was especially associated with EBVa GC.

Meta-analysis of the relationship between Epstein-Barr virus infection and clinicopathological features of patients with gastric carcinoma

Epstein-Barr virus (EBV) infection has been causally associated with occurrence of many malignant neoplasms. EBV-encoded small RNAs (EBERs) have been detected from about 10% of gastric carcinoma tissue cells, suggesting that EBV infection is associated with the development of gastric carcinoma. The present study pooled the data from the papers concerning EBV-related gastric cancers and performed a meta-analysis of 22 research papers. Among these papers, a total of 5475 cases with gastric cancer were enrolled, of whom 411 cases were found EBV-positive, with the EBV-positive rate being 7.5%. Among the EBV-positive gastric cancer cases, the detection rate was 11.1% in males and 3.0% in females. Compared with EBV-negative gastric cancer, EBV-positive gastric cancer had less lymph node metastasis. Based on the histological typing, of the EBV-positive gastric cancers, the diffuse type was 8.1%, and intestinal type was 8.0%. The examined specimen types included stored paraffin blocks and fresh surgically removed specimens, their EBV positive rates were 7.9% and 6.5% respectively. In terms of geographical distribution, the detection rate of EBV-positive gastric cancer was 9.4% in America, 6.1% in Asia and 9.1% in Europe. Meta-analysis showed that EBV infection occurred only in gastric cancer tissue cells and was significantly associated with the patients’ gender, lymph node metastases, and the location where tumor tissue generated and geographical distribution (P【0.05), but was not significantly associated with the patients’ histological types of tumor and the types of specimens (P】0.05). These results suggested that EBV-positive gastric cancer has distinct clinicopathological features.

Relationship between abnormality of FHIT gene and EBV infection in gastric cancer

AIM: To examine the aberrant expression of fragile histidine triad (FHIT) gene and protein in gastric cancer, and to evaluate the role of FHIT gene and the relationship between FHIT gene and EBV infection in gastric carcinogenesis. METHODS: FHIT transcripts were detected by nested RT-PCR in 30 cases of gastric cancer and their products were sequenced.FHIT protein was detected by Western blot. EBV infection was detected by PCR method in 50 cases of gastric cancer. RESULTS: The wild type transcripts were detected in all 30 matched normal tissues of gastric cancer.Aberrant transcripts were found in 11/30 (36.7%) gastric cancerous tissues. Sequencing analysis of the aberrant fragments found an RT-PCR product missing exons 5-7 in one case of gastric cancer, and another product missing exons 4-7. Four of ten (40.0%) cases of primary gastric cancer showed absent or decreased expression of FHIT protein as compared with their matched normal tissues.EBV was detected in 5/50 (10%) gastric cancers,among which 4/5 (80%) had aberrant transcripts of FHIT gene. CONCLUSION: Loss of FHIT gene or FHIT protein plays an important role in carcinogenesis,development and progression of gastric cancer.EBV infection might influence carcinogenesis of gastric cancer by inducing the abnormality of FHIT gene.

EB病毒与相关性胃癌研究进展

EB病毒(Epstein-Barr virus,EBV)于40年前从1个伯基特淋巴瘤活组织切片中发现,是发现的第1个与人类癌症直接相关的病毒.他是一个常见的人类病原体,与宿主保持平衡的状态,在极少数情况下,宿主一病毒之间的平衡被打乱.从而造成不同群体的恶性肿瘤.EBV与上皮细胞肿瘤特别是鼻咽癌和EBV阳性胃癌相关性还不是太清楚,目前认为是病毒在上皮细胞中显示癌前病变病变的基因变化的后果.约10%的胃癌中有克隆的EBV.本文对EBV在胃癌发生发展中的作用进行了讨论,包括流行病学和临床研究.

EB病毒与胃癌发生的研究进展

全球恶性肿瘤发病率中胃癌居第2位,近年来的研究不断证实Epstein-Barr(EB)病毒存在于胃癌细胞中,EB病毒相关胃癌(Epstein-Barr virus-associated gastric carcinoma,EBVaGC)逐渐被人们所了解和认知.全球胃癌患者中平均有7.5%是EBVaGC,预计每年有80000新增EBVaGC患者.EBVaGC具有自己独特的临床病理学特性,EB病毒编码的小RNA在肿瘤细胞中表达而不在正常上皮细胞中表达,说明EB病毒在胃癌的发生中起着重要的作用.本文对EB病毒及EBVaGC做一综述.

EBVaGC临床病理因素分析及其微血管、微淋巴管生成的机制研究

目的检测EB病毒相关性胃癌(EBVaGC)的阳性率及分析其临床病理特征,探讨EBVaGC微血管生成、微淋巴管生成的可能机制。方法利用原位分子杂交技术检测EBV编码小RNA1,从600例胃癌组织标本中,筛选出EB病毒相关性胃癌组织标本,对其采用免疫组化方法检测LMP1、BHRF1、VEGF-C、LYVE-1和CD34的表达水平,分析其可能存在的关系。结果在600例胃癌标本中EBVaGC的阳性率为5.0%,临床病理因素分析发现EBVaGC与性别、病理类型、发生部位及淋巴结转移有关(P<0.05),而与年龄无关(P>0.05)。在30例EBVaGC标本中LMP1呈低表达,与性别、分期及周围淋巴结转移无关(P>0.05),而BHRF1、VEGF-C高表达,均与TNM分期和周围淋巴结转移有明显的关系(P<0.05);EBVaGC中MVD与性别及周围淋巴结转移无关,而与TNM分期显著有关(P<0.05);MLVD与TNM分期和周围淋巴结转移密切相关(P<0.05)。BHRF1的表达与MVD无显著关系,而与MLVD有明显差异(P<0.05)。VEGF-C阳性表达的19例EBVaGC组织中,MVD和MLVD均明显高于阴性组,两组比较其差异具有显著的统计学意义(P<0.05)。结论 EBVaGC与性别、病理类型、发生部位及淋巴结转移有关,而与年龄无关。EBVaGC中LMP1的表达率低,BHRF1的表达率高,可能与EBVaGC较少发生淋巴结转移有关。VEGF-C可能参与EBVaGC的微血管和微淋巴管生成,其高表达间接促进肿瘤细胞沿新生的淋巴管迁徙和转移。

EBV相关性伴淋巴样间质胃癌4例临床病理分析

目的探讨EBV相关性伴淋巴样间质胃癌(Epstein-Barr virus-associated gastric carcinoma with lymphoid stroma,EBVaGCLS)的临床病理学特征、免疫表型、分子遗传学特征及预后。方法收集4例EBVaGCLS的临床病理学资料,采用免疫组化EnVision两步法及原位杂交法标记肿瘤细胞,分析其临床、病理形态学特征,及与预后的关系,并复习相关文献。结果4例均为男性,年龄60~66岁,平均62岁。肿瘤位于近端胃,最大径4.2~8.7 cm,平均6.8 cm。癌组织浸润性生长,一般呈梁状、条索状、片状或不规则腺管状。肿瘤细胞较大,合体样多角形。间质伴大量成熟淋巴细胞浸润,可形成淋巴滤泡。免疫表型:肿瘤细胞CKpan、CK-L、CK7、错配修复蛋白(MLH1、PMS2、MSH2、MSH6)均阳性,间质淋巴细胞CD3、CD20均阳性,AFP、Heppar-1均阴性,Ki-67增殖指数为20%~80%。4例EBER原位杂交均呈阳性。4例患者平均随访9个月,其中1例死亡。结论EBVaGCLS多发生于中老年人,临床症状相较于分化型胃癌无特殊,诊断和鉴别诊断依赖于其特征性形态学表现并辅以免疫组化、原位杂交检测。EBVaGCLS预后好于EBV阴性胃癌,治疗以手术完整切除为主。