Is gastric lymphoepithelioma-like carcinoma a special subtype of EBV-associated gastric carcinoma? New insight based on clinicopathological features and EBV genome polymorphisms.

BACKGROUND: Gastric lymphoepithelioma-like carcinoma (LELC) is a rare entity that is closely associated with Epstein-Barr virus (EBV). However, the EBV latency pattern and genome polymorphisms in gastric LELC have not been systematically explored. METHODS: The clinicopathological features, EBV latency pattern and genome polymorphisms of EBV-positive gastric LELC in Guangzhou, southern China were investigated and compared with those of ordinary EBV-associated gastric carcinoma (EBVaGC) in the same area. RESULTS: Ten (1.42%) of 702 gastric carcinoma cases were identified as gastric LELC, in which eight (80%) cases were EBV-positive. The clinicopathological characteristics and EBV latency pattern of EBV-positive gastric LELC were similar to those of ordinary EBVaGC. In EBV genotype analysis, type A strain, type F, I, mut-W1/I, XhoI- and del-LMP1 variants were predominant among EBV-positive gastric LELCs, accounting for eight (100%), six (75%), eight (100%), seven (87.5%), five (62.5%) and six (75%) cases, respectively, which are similar to those in ordinary EBVaGC. For EBNA1 polymorphisms, the V-leu and P-ala subtypes were predominant in EBV-positive gastric LELC, which is different from the predominant V-val subtype in ordinary EBVaGC. EBV-positive gastric LELC has a favorable prognosis when compared to ordinary EBVaGC (median survival time 43.0 vs. 18.0 months). CONCLUSIONS: Gastric LELC is strongly associated with EBV and EBV-positive gastric LELC should be regarded as a special subtype of EBVaGC. This, to our best knowledge, is the first time in the world that the EBV latency pattern and genome polymorphisms of EBV-positive gastric LELC are systematically revealed.

Association of distinctive Epstein-Barr virus variants with gastric carcinoma in Guangzhou, southern China.

To investigate the clinicopathologic features, Epstein-Barr virus (EBV) latency pattern and genome polymorphism of EBV-associated gastric carcinoma (EBVaGC) in Guangzhou, an endemic area of nasopharyngeal carcinoma (NPC), an in situ hybridization assay of EBV-encoded small RNA-1 (EBER-1) was used to identify the presence of EBV in 676 consecutive gastric carcinoma cases. EBV-encoded proteins EBNA1, EBNA2, LMP1, and ZEBRA were detected by immunohistochemistry. EBV genome polymorphism was also analyzed by PCR and DNA sequencing. Of the 676 cases, 45 EBV-positive cases (6.7%) were identified, including 37 (8.5%) male and 8 (3.3%) female cases. EBNA1 was detected in 42 cases (93.3%), while EBNA2, LMP1, and ZEBRA were all negative. In the EBV genome polymorphism analysis, type A strain, prototype F, type I, XhoI-, and del-LMP1 variants were predominant among EBVaGC patients, accounting for 44 (97.8%), 37 (82.2%), 45 (100%), 34 (75.6%), and 42 (93.3%) cases, respectively. Moreover, a new hotspot mutation in the BamHI-W1/I1 boundary region (148,972 T --> C) was found in 39 (86.7%) of the 45 cases. The predominant EBV variants in EBVaGC in Guangzhou are prototype F, type I, and XhoI-, which are different from those in NPC in this area (predominant variant-type "f") and in EBVaGC in Latin American countries (predominant type "i" and XhoI+), suggesting that the EBV variants are not only geographically distributed but also disease restricted, and the pathogenic role of EBV in different EBV associated epithelial malignancies in different areas may be distinct.

[Clinicopathologic features and protein expression study of Epstein-Barr virus-associated gastric carcinoma in Guangzhou].

OBJECTIVE: To 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. METHOD: A 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. RESULTS: Forty-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). CONCLUSIONS: EBV 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.

Frequency of IL-10-producing regulatory B cells associated with disease activity in thyroid-associated orbitopathy.

AIM: To investigate the association between IL-10-producing regulatory B (B10) cells and the clinical features of thyroid-associated orbitopathy (TAO). METHODS: A total of 30 patients with TAO were recruited at Zhongshan Ophthalmic Center from May 2015 to December 2015. Peripheral blood mononuclear cells (PBMCs) were separated from blood samples of 30 TAO patients and 16 healthy controls and stimulated with CD40 ligand and CpG for 48h. The frequency of IL-10+ B cells was examined by flow cytometry and the correlation between the frequency of IL-10+ B cells and clinical features of TAO was analyzed by SPSS. RESULTS: The frequency of IL-10+ B cells among CD19+ B cells in TAO patients was significantly lower than in healthy controls (TAO: 4.66%±1.88% vs healthy control: 6.82%±2.40%, P<0.01). The frequency of IL-10+ B cells showed a positive correlation with disease activity of TAO measured by Clinical Activity Score (CAS) (r=0.50, P<0.01), and became higher in TAO patients with family history of Graves' disease (GD) (P=0.04). CONCLUSION: The decrease of the frequency of IL-10+ B cells in TAO patients indicates the deficiency of B10 cells in TAO, and the positive association with disease activity suggests its important role in TAO inflammation regulation.

Clinical characteristics and prognosis of patients with retinoblastoma: 8-year follow-up.

BACKGROUND/AIM: The aim of this study was to investigate the potential correlation between clinical characteristics and prognosis of patients with retinoblastoma (Rb). MATERIALS AND METHODS: This retrospective study included 314 Rb patients. Clinical data including laterality of eyes, sex, age, presenting signs, lag time, and survival were recorded and analyzed. RESULTS: Leukocoria is the most common clinical presentation of Rb. Patients with isolated leukocoria had shorter lag time and exhibited a high survival rate (85%, 5 years). Patients with strabismus and blurred vision, and who were older and had longer lag time, exhibited an excellent survival rate (100% and 92.3%, respectively, 5 years). Patients with exophthalmos had the longest lag time and the lowest survival rate (17.8%, 5 years). The 5-year survival rate of patients with a lag time of 6 months was 84.7%, which was significantly higher than that of patients with a lag time of > 6 months (64.7%). CONCLUSION: Leukocoria, strabismus, and blurred vision are mild clinical manifestations of Rb that are associated with better disease prognosis, whereas exophthalmos is an indicator of poor prognosis. Long lag time is a risk factor for the survival of Rb, which can be avoided. Early detection and treatment can greatly improve the survival of Rb patients.

Sequence variations of latent membrane protein 2A in Epstein-Barr virus-associated gastric carcinomas from Guangzhou, southern China.

Latent membrane protein 2A (LMP2A), expressed in most Epstein-Barr virus (EBV)-associated malignancies, has been demonstrated to be responsible for the maintenance of latent infection and epithelial cell transformation. Besides, it could also act as the target for a CTL-based therapy for EBV-associated malignancies. In the present study, sequence variations of LMP2A in EBV-associated gastric carcinoma (EBVaGC) and healthy EBV carriers from Guangzhou, southern China, where nasopharyngeal carcinoma (NPC) is endemic, were investigated. Widespread sequence variations in the LMP2A gene were found, with no sequence identical to the B95.8 prototype. No consistent mutation was detected in all isolates. The immunoreceptor tyrosine-based activation motif (ITAM) and PY motifs in the amino terminus of LMP2A were strictly conserved, suggesting their important roles in virus infection; while 8 of the 17 identified CTL epitopes in the transmembrane region of LMP2A were affected by at least one point mutation, which may implicate that the effect of LMP2A polymorphisms should be considered when LMP2A-targeted immunotherapy is conducted. The polymorphisms of LMP2A in EBVaGC in gastric remnant carcinoma (GRC) were for the first time investigated in the world. The LMP2A sequence variations in EBVaGC in GRC were somewhat different from those in EBVaGC in conventional gastric carcinoma. The sequence variations of LMP2A in EBVaGC were similar to those in throat washing of healthy EBV carriers, indicating that these variations are due to geographic-associated polymorphisms rather than EBVaGC-associated mutations. This, to our best knowledge, is the first detailed investigation of LMP2A polymorphisms in EBVaGC in Guangzhou, southern China, where NPC is endemic.

Variations of Epstein-Barr virus nuclear antigen 1 in Epstein-Barr virus-associated gastric carcinomas from Guangzhou, southern China.

Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is the only viral protein consistently expressed in all EBV-associated malignancies, and play a critical role in the onset, progression, and/or maintenance of these tumors. Based on the signature changes at amino acid residue 487, EBNA1 is classified into five distinct subtypes: P-ala, P-thr, V-leu, V-val and V-pro. In the present study, the sequence variations of EBNA1 in EBV-associated gastric carcinoma (EBVaGC) and throat washing (TW) samples of healthy EBV carriers in Guangzhou, southern China, where nasopharyngeal carcinoma (NPC) is endemic, were analyzed by PCR and DNA sequencing. V-val subtype was the most predominant (53.6%, 15/28) in EBVaGC, followed by P-ala (42.9%, 12/28) and V-leu (32.1%, 9/28) subtypes. In TWs of healthy EBV carriers, V-val subtype was also predominant (85.7%, 18/21). The sequence variations of EBNA1 in EBVaGC were similar to those in TW of healthy EBV carriers (p>0.05), suggesting that the EBV strains in EBVaGC might originate from the viral strains prevalent within the background population. The predominance of V-val subtype in EBVaGC in Guangzhou was similar to that in EBVaGC in northern China and Japan, but was different from that in EBVaGC in America, suggesting that the variations of EBNA1 in EBVaGC represent geographic-associated polymorphisms rather than tumor-specific mutations. In addition, the EBNA1 variations in EBVaGC in gastric remnant carcinoma were also determined. V-leu subtype was detected in all 4 (100%) cases, although 2 cases occurred as mixed infection with P-ala subtype. This is different from the predominant V-val subtype in EBVaGC in conventional gastric carcinoma, suggesting that V-leu might be a subtype that adapts particularly well to the microenvironment within the gastric stump and enters the remnant gastric mucosa epithelia easily. This, to our best knowledge, is the first investigation of EBNA1 polymorphisms in EBVaGC from endemic area of NPC.

Low expression of Beclin 1, associated with high Bcl-xL, predicts a malignant phenotype and poor prognosis of gastric cancer.

Recent studies have suggested that dysregulation of autophagy plays a pivotal role in tumorigenesis. Here, we determined the prognostic value of autophagy-related protein Beclin 1 in gastric cancer. A total of 153 primary gastric cancer patients were subjected to analysis of Beclin 1 expression and survival prognosis. Among them, 68 patients were assigned randomly and used as a training set to generate a cutoff score for Beclin 1 expression by receive operating characteristic (ROC) curve analysis. The ROC-generated cutoff score was subjected to analyze the association of Beclin 1 with clinical characteristics and patient outcome. In a testing set (n = 85) and overall patients (n = 153), both univariate and multivariate analysis found that low expression of Beclin 1 predicted adverse overall survival and progression-free survival for gastric cancer patients. Furthermore, in each stage of gastric cancer patients, Beclin 1 expression was a prognostic indicator in patients with stage II, III and IV. Importantly, a reverse relationship between Beclin 1 and Bcl-xL expression was demonstrated. In patients of elevated Bcl-xL expression, a subset with lower Beclin 1 expression displayed an inferior overall survival and progression-free survival than those with higher Beclin 1 expression. Thus, our data demonstrated that low expression of Beclin 1, associated with high Bcl-xL, played as an independent biomarker, contributing to a more aggressive cancer cell phenotype and poor prognosis for gastric tumor.

Epstein-Barr virus genome polymorphisms of Epstein-Barr virus-associated gastric carcinoma in gastric remnant carcinoma in Guangzhou, southern China, an endemic area of nasopharyngeal carcinoma.

Epstein-Barr virus (EBV) is associated with a subset of gastric carcinoma which was defined as EBV-associated gastric carcinoma (EBVaGC). The proportion of EBVaGC in gastric remnant carcinoma (GRC) was apparently higher than that in conventional gastric carcinoma (CGC) which occurs in the intact stomach. To clarify the possible mechanisms, 26 GRC cases from Guangzhou were investigated for the presence of EBV, and the EBV genome polymorphisms of EBVaGC in GRC were analyzed. Besides, the clinicopathologic characteristics, EBV latency pattern of EBVaGC in GRC were also investigated. Eight (30.8%) out of 26 cases were identified as EBVaGCs. Type A strain, prototype F, type I, mut-W1/I1, XhoI- and del-LMP1 variants were predominant among EBVaGC patients, accounting for 7 (87.5%), 7 (87.5%), 8 (100%), 6 (75%), 5 (62.5%) and 8 (100%) cases, respectively. All EBVaGC cases were male and with the histology of diffuse-type carcinoma. The tumor cells expressed EBNA1 (87.5%) and LMP2A (62.5%) but not LMP1, EBNA2 and ZEBRA. Thus, the EBV latency pattern was latency I. These were similar to those in CGC, except for the significantly higher proportion of EBVaGC in GRC than in CGC, suggesting that there is no more aggressive EBV variant in EBVaGC in GRC, and the injuries of gastric mucosa and/or changes of the microenvironment within the remnant stomach may be involved in the development of EBVaGC in GRC. This, to our knowledge, is the first study concerning about the EBV genome polymorphisms of EBVaGC in GRC in the world.