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41.
42.
EBV-LMP1对鼻咽癌细胞系CNE1细胞转移相关因素的影响 总被引:10,自引:0,他引:10
背景与目的:已证实EB病毒(Epstein-Barrvirus,EBV)编码的潜伏膜蛋白1(latentmembraneprotein1,LMP1)能够诱导鼻咽癌细胞中基质金属蛋白酶9(matrixmetalloproteinase-9,MMP-9)的表达。本实验的目的是观察EB病毒潜伏膜蛋白1(EBV-LMP1)对鼻咽癌细胞系CNE1细胞转移相关因素的影响,探讨LMP1在鼻咽癌侵袭、转移过程中的作用。方法:用免疫组化法及Westernblot法检测CNE1-GL(转染LMP1基因的CNE1细胞)和CNE1细胞中MMP-9的表达情况;用细胞-基质粘附实验、细胞运动实验和肿瘤细胞重组基底膜侵袭实验检测LMP1对CNE1细胞粘附、运动及侵袭能力的影响。结果:免疫组化法及Westernblot法结果均显示CNE1-GL细胞中MMP-9的表达明显高于CNE1细胞(P<0.05);肿瘤细胞-基质粘附实验结果显示,CNE1-GL的粘附能力(平均吸光度值为1.2508±0.0711),高于CNE1细胞(平均吸光度值为0.9519±0.068),两者相比差异有显著性(P<0.01)。运动实验及重组基底膜侵袭实验结果均显示,穿过游离的聚乙烯吡咯烷酮膜(polyvinylpyrroli-done-free,PVP-F)的CNE1-GL细胞数明显高于CNE1细胞(P<0.01)。结论:LMP1能够诱导CNE1细胞中MMP-9的表达,且增强CNE1细胞与基底膜的粘附能力、运动能力及侵袭能力。 相似文献
43.
Ohshima K Muta K Nakashima M Haraoka S Tutiya T Suzumiya J Kawasaki C Watanabe T Kikuchi M 《International journal of cancer. Journal international du cancer》2001,93(1):91-96
RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is present in neoplastic cells, induces apoptosis of natural killer (NK)/T cells and plays a role in immune evasion. Fas ligand (FasL) is considered to have similar roles. The Epstein-Barr virus (EBV)-encoded latent membrane protein is expressed by malignant Hodgkin and Reed-Sternberg (H&RS) cells of EBV-associated Hodgkin's disease (HD) and considered to be a target of cytotoxic T lymphocytes (CTLs). However, CTL response is inadequate in HD. To determine whether RCAS1 and FasL are expressed in EBV-associated HD and participate in immune evasion, tissues of 20 EBV(-) and 15 EBV(+) HD cases were immunohistochemically stained for RCAS1, FasL and HLA classes I and II, whose deficiencies could explain CTL escape. Lymphocytes surrounding H&RS cells tended to be CD4(+) cells and rarely CD8(+), TIA-1(+) (cytotoxic marker) or NK cells. HLA class I and/or II were expressed in all EBV(+) HD cases, and RCAS1-expressing H&RS cells were found in 14/15 (93%) EBV(+) HD cases but only 8/20 (40%) EBV(-) HD cases (p < 0.05). FasL was detected in 9/15 (60%) and 7/20 (35%) EBV(+) and EBV(-) HD cases, respectively. ssDNA-positive (apoptotic) lymphocytes, surrounding H&RS cells, were rarely seen but were present in RCAS1(+) cases (20/22 cases, 91%) rather than negative cases (0/13 cases, 0%) (p < 0.005). Our findings suggest that EBV(+) H&RS cells might evade the host immune response by expressing RCAS1 rather than FasL. 相似文献
44.
Gahn B Siller-Lopez F Pirooz AD Yvon E Gottschalk S Longnecker R Brenner MK Heslop HE Aguilar-Cordova E Rooney CM 《International journal of cancer. Journal international du cancer》2001,93(5):706-713
The EBV-encoded LMP2A protein is consistently expressed in EBV(+) Hodgkin's lymphoma and can be targeted by CTLs. CTLs stimulated conventionally by LCLs have little activity against LMP2A(+) target cells. Here, we describe an alternative approach, based on the in vitro stimulation of CTLs with DCs genetically modified with 2 E1/E3-deleted recombinant adenoviruses, AdGFPLMP2A, encoding a fusion gene of GFP and LMP2A, and AdLMP2A, encoding LMP2A only. Transduction of DCs with AdGFPLMP2A at MOI 1,000 resulted in LMP2A expression in up to 88% of DCs. LMP2A protein was expressed in 40% of DCs transduced with AdLMP2A at an MOI of 100. Higher MOI resulted in DC death. CTL lines activated by transduced DCs had a higher frequency of LMP2A tetramer-specific CTLs than CTL lines activated by LCLs. CTLs stimulated with transduced DCs lysed both autologous fibroblasts infected with vaccinia virus LMP2A (FBvaccLMP2A) and autologous LCLs, which express LMP2A at lower levels. In contrast, CTLs generated from the same donors by stimulation with autologous LCLs showed minimal lysis of FBvaccLMP2A. Moreover, 1 donor who did not respond to LMP2A when CTLs were stimulated with LCLs became a responder when LMP2A was expressed by transduced DCs. Hence, recombinant adenoviruses encoding LMP2A effectively transduce DCs and direct the generation of LMP2A-specific CTLs. This approach will be a potent strategy in Hodgkin's lymphoma immunotherapy. 相似文献
45.
Successful renal transplantation for Epstein syndrome 总被引:2,自引:0,他引:2
B M Alving P G Tarassoff J Moore C A Leissenger C Fernandez-Bueno 《American journal of hematology》1986,21(1):111-113
Successful cadaveric renal transplantation was accomplished in a patient with Epstein syndrome, a triad of macrothrombocytopenia, partial high-frequency hearing loss, and nephritis, which often progresses to complete renal failure. The success of the transplant demonstrates that the macrothrombocytopenia which occurs in this syndrome is not a contraindication to aggressive management of end-stage renal disease. 相似文献
46.
The Epstein‐Barr virus (EBV) is the aetiological agent of classical infectious mononucleosis. This review article describes the antigenicity of the virus, the specific antibody response and the stimulated polyclonal heterophile antibody production in the host. The diagnostic tests for EBV infection are discussed, with particular attention drawn to the pitfalls of the Monospot test. Complications are listed and management strategies are outlined. The uses and complications of steroids are discussed. The importance of avoidance of contact sport and the association with splenic rupture is described. 相似文献
47.
48.
49.
Michael C. Lee Fei Dong Andrew J. Stephenson J. Stephen Jones Cristina Magi-Galluzzi Eric A. Klein 《European urology》2010
Background
Few reports attempt to validate the role of Epstein criteria in selecting patients for an active surveillance protocol.Objective
To determine the performance of the Epstein biopsy criteria for predicting pathologic end points and biochemical relapse-free survival (bRFS) in men with early stage prostate cancer (PCa) treated by radical prostatectomy (RP).Design, setting, and participants
Between October 1999 and January 2007, 746 consecutive patients were biopsied, and then underwent RP at our tertiary care institution. Two hundred sixty-eight patients met the entry criteria of Gleason 6 disease only on initial biopsy with complete pathologic information.Measurements
Primary end point was insignificant disease. Insignificant disease was defined using a classical (organ-confined, Gleason score <6, and tumor volume <0.5 cm3) and more liberal (organ-confined, Gleason <6 tumor of any volume) formulation. Secondary end points included organ-confined disease and bRFS.Results and limitations
One hundred thirty-six men (51%) met the Epstein biopsy criteria, and 167 (62%) had organ-confined cancer. Insignificant disease by the classical and liberal definitions was present in 68 (25%) and 92 (34%) patients, respectively. Cases meeting Epstein biopsy criteria were more likely to have insignificant disease by either definition (p < 0.001) and more likely to have organ-confined tumors (p < 0.001). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) varied widely among the end points, with sensitivity (74%) and NPV (86%) best for the classical definition of insignificant disease and specificity (74%) and PPV (92%) best for organ-confined disease. The estimated 5-yr bRFS was 100% for those meeting Epstein biopsy criteria compared to 83% for those not meeting these criteria.Conclusions
The Epstein biopsy criteria predict for a high likelihood of organ-confined disease and the absence of biochemical failure up to 5 yr after RP. These criteria are insufficiently robust to predict the presence of biologically insignificant disease. 相似文献50.