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EBV-encoded Small RNAs (EBV-encod + small_rna)
Selected AbstractsEpstein-Barr virus associated gastric carcinoma: Epidemiological and clinicopathological featuresCANCER SCIENCE, Issue 2 2008Suminori Akiba In this paper, the roles of Epstein-Barr virus (EBV) in gastric carcinogenesis are discussed, reviewing mainly epidemiological and clinicopathological studies. About 10% of gastric carcinomas harbor clonal EBV. LMP1, an important EBV oncoprotein, is only rarely expressed in EBV-associated gastric carcinoma (EBV-GC) while EBV-encoded small RNA is expressed in almost every EBV-GC cell, suggesting its importance for developing and maintaining this carcinoma. In addition, the hypermethylation-driven suppressor gene downregulation, frequently observed in EBV-GC, appears to give a selective advantage for carcinoma cells. EBV reactivation is suspected to precede EBV-GC development since antibodies against EBV-related antigens, including EBV capsid antigen (VCA), are elevated in prediagnostic sera. Interestingly, the average anti-VCA immunoglobulin G antibody titer in EBV-GC patients was significantly higher among men than among women, whereas EBV-negative GC cases did not show such a sex difference. A higher frequency of human leucocyte antigen-DR11 in EBV-GCs suggests that major histocompatibility complex-restricted EBV nuclear antigen 1 epitope recognition may enhance EBV reactivation. EBV infection of gastric cells by lymphocytes with reactivated EBV is suspected to be the first step of EBV-GC development. Male predominance of EBV-GC suggests the involvement of lifestyles and occupational factors common among men. The predominance of EBV with XhoI+ and BamHI type i polymorphisms in EBV-GC in Latin America suggests a possibility of some EBV oncogene expressions being affected by EBV polymorphism. The lack of such predominance in Asian countries, however, indicates an interaction between EBV polymorphism and the host response. In conclusion, further studies are necessary to examine the interaction between EBV infection, its polymorphisms, environmental factors, and genetic backgrounds. (Cancer Sci 2008; 99: 195 ,201) [source] Extranodal NK/T-cell lymphoma, nasal type, presenting after 5 years of remissionINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 3 2008Tomonobu Ito MD A 76-year-old woman with multiple edematous erythemas, erosions, and ulcers on the breast and abdomen was admitted to our hospital in June 2005. She had developed granulomatous bleeding lesions in the right nostril 6 years prior to her visit to our dermatology unit. She had been observed at the otorhinolaryngology department of our hospital, and a biopsy was taken from the nasal lesion. Computerized tomography and gallium scintigraphy (67Ga single-photon emission computed tomography) did not reveal any lesions corresponding to the diagnosis of malignant lymphoma. The histologic examination of the nasal specimen rendered a diagnosis of natural killer (NK)/T-cell lymphoma, nasal. Because imaging analysis indicated a small-sized tumor without metastases, oral prednisolone at 20 mg/day was administered for 1 month. The tumor decreased in size and disappeared after 19 months of low-dose steroid therapy. ,Five years after the initial treatment, the patient developed a fever of 38 °C with infiltrated erythemas and erosions on her breast. Erysipelas was initially suspected, but the antimicrobial agent did not show any effect and the multiple infiltrated erythemas and ulcers spread throughout her chest and abdomen (Fig. 1). The lymph nodes were not palpable. The right nasal cavity showed no granulomatous lesions or other signs of abnormality. The peripheral white blood cell count (3000/µL), red blood cell count (3.54 × 106/µL), and platelet count (112 × 103/µL) were reduced. Atypical lymphocytes were not observed. The serum lactic dehydrogenase (LDH; 1770 U/L; normal, 224,454 U/L), aspartate aminotransferase (AST; 140 U/L; normal, 10,30 U/L), and alanine aminotransferase (ALT; 57 U/L; normal, 3,29 U/L) levels were elevated. The soluble interleukin-2 (IL-2) receptor level was high (25,300 U/mL; normal, 167,497 U/mL). Epstein,Barr virus (EBV) serologic examination showed the immunoglobulin G (IgG) viral capsid antigen (VCA) at 1 : 320 and the EBV nuclear antigen (EBNA) at 1 : 40. IgM VCA and EBV early antigen-diffuse restricted antibody (EA) IgA and IgG were not detectable. Histologic findings from the left chest skin showed a distribution of atypical lymphocytes from the upper dermis to the subcutaneous tissue, and many foamy cells which had phagocytosed the hemocytes (Fig. 2a,b). Immunohistochemical analysis showed that the atypical lymphocytes were sCD3,, CD4,, CD8,, CD20,, CD56+, granzyme B+, and T-cell intracellular antigen (TIA-1) positive. Furthermore, EBV-encoded small RNAs (EBER), detected by in situ hybridization, exhibited a strong signal. The nasal lesions biopsied 6 years previously showed an identical staining pattern with the skin lesions immunohistochemically. Analysis of the T-cell receptor-, (TCR-,), TCR-,, and TCR-, gene did not reveal any clonal rearrangements, but the EBV gene was detected from the skin specimens by Southern blotting. Our patient's condition was diagnosed as a case of extranodal NK/T-cell lymphoma, nasal type, but the patient had concomitantly developed hemophagocytic syndrome (HPS). She was treated with a combination of steroid pulse therapy and chemotherapy (pirarubicin hydrochloride 30 mg/m2, cyclophosphamide 500 mg/m2, vincristine 1 mg/m2, prednisolone 30 mg/m2, etoposide 80 mg/m2). After the first session of chemotherapy, the lesions on the chest and abdomen diminished, but, 2 weeks later, the skin lesions recurred, and disseminated intravascular coagulation (DIC) induced by HPS supervened. The patient died as a result of multiple organ failure induced by HPS. Figure 1. Multiple infiltrated erythemas, erosions, and ulcers on the breast and abdomen Figure 2. Histologic findings of a skin biopsy specimen from the left chest (hematoxylin and eosin staining). (a) Dense infiltration of atypical lymphocytes from the upper dermis to the subcutaneous tissue (×40). (b) Many foamy cells had phagocytosed the hemocytes (×400) [source] Epstein-Barr Virus (EBV) Latent Membrane Protein 1 Induces Interleukin-8 through the Nuclear Factor-,B Signaling Pathway in EBV-Infected Nasopharyngeal Carcinoma Cell LineTHE LARYNGOSCOPE, Issue 5 2004Qingchun Ren MD Abstract Background/Objectives: Nasopharyngeal carcinoma (NPC) is a highly invasive and metastatic malignant tumor and is associated with Epstein-Barr virus (EBV) infection that exhibits type II latency. Angiogenesis is essential for tumor growth, invasion, and metastasis. Our previous studies have indicated that interleukin (IL)-8 was over-expressed in many NPC tissues and was found to be significantly correlated with angiogenesis by immunohistochemistry. Study Design: In vitro design. Methods: The influence of the EBV genome for IL-8 gene expression was studied using the EBV,genome-positive and -negative epithelial/NPC hybrid cell line NPC-KT. The EBV-positive and -negative clones were selected by polymerase chain reaction and in situ hybridization. Results: EBV-positive clones expressed abundant IL-8 mRNA compared with EBV-negative clones. This result indicated that over-expression of IL-8 depended on the presence of EBV genomes in NPC-KT cells. Two encoded genes, latent membrane protein (LMP)1 and EBV-encoded small RNAs (EBERs), expressed in NPC were transfected in EBV-negative NPC-KT cells. LMP1 transactivated the IL-8 promoter, whereas EBERs did not. Moreover, the nuclear factor (NF)- ,B binding site in the IL-8 promoter was essential for the response to LMP1, and the activator protein (AP)-1 binding site played only a partial role. Conclusions: LMP1 induces IL-8 mainly through the activation of NF-,B and partly through AP-1 in NPC model cell lines, NPC-KT, and this suggests that LMP1 plays an important role in the angiogenesis of NPC. [source] Epstein-Barr virus persistence and reactivation in myasthenia gravis thymusANNALS OF NEUROLOGY, Issue 6 2010Paola Cavalcante PhD Objective Increasing evidence supports a link between Epstein-Barr virus (EBV), a ubiquitous B-lymphotropic human herpesvirus, and common B-cell,related autoimmune diseases. We sought evidence of EBV infection in thymuses from patients with myasthenia gravis (MG), an autoimmune disease characterized by intrathymic B-cell activation. Methods Seventeen MG thymuses (6 follicular hyperplastic, 6 diffuse hyperplastic, 5 involuted) and 6 control thymuses were analyzed using in situ hybridization for EBV-encoded small RNAs (EBERs), immunohistochemistry for EBV latent and lytic proteins, and polymerase chain reaction for EBV DNA and mRNA. Results All 17 MG thymuses showed evidence of active EBV infection, whereas none of the control thymuses were infected. Cells expressing EBERs (12 of 17) and EBV latency proteins (EBNA2, LMP1, and LMP2A) (16 of 17) were detected in medullary infiltrates and in germinal centers. Cells expressing early (BFRF1, BMRF1) and late (p160, gp350/220) lytic phase EBV proteins were present in 16 MG thymuses. Latency (EBNA1, LMP2A) or lytic (BZLF1) transcripts (often both) were present in all MG thymuses, and EBV DNA (LMP1 gene) was detected in 13 MG thymuses. We also found CD8+ T cells, CD56 + CD3-natural killer cells, and BDCA-2+ plasmacytoid dendritic cells in immune infiltrates of MG thymuses, but not germinal centers, suggesting an attempt of the immune system to counteract EBV infection. Interpretation Dysregulated EBV infection in the pathological thymus appears common in MG and may contribute to the immunological alterations initiating and/or perpetuating the disease. ANN NEUROL 2010;67:726,738 [source] | ||||||||||