...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Molecular Carcinogenesis >Stable expression of EBERs in immortalized nasopharyngeal epithelial cells confers resistance to apoptotic stress.
【24h】

Stable expression of EBERs in immortalized nasopharyngeal epithelial cells confers resistance to apoptotic stress.

机译：EBERs在永生化的鼻咽上皮细胞中的稳定表达赋予对凋亡压力的抗性。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Epstein-Barr virus (EBV) infection is closely associated with the development of nasopharyngeal carcinoma (NPC). The EBV-encoded RNAs (EBERs) are the most abundant EBV transcripts (about 10(7) copies per cell) in EBV infected cells. However, the cellular function of EBER expression, particularly in nasopharyngeal epithelial cells, remains poorly understood. EBERs acquire secondary structures analogous to double-stranded RNA (dsRNA) and may bind to the double-stranded RNA-dependent protein kinase (PKR) and interfere with its function. Activation of PKR involves autophosphorylation resulting in protein synthesis inhibition and cellular apoptosis. Induction of cellular apoptosis by activation of PKR may be an antiviral response adopted by virally infected cells. We have examined the functional properties of EBER expression in an immortalized nasopharyngeal epithelial cell line (NP69). Expression of EBERs was achieved by transfecting the NP69 cells with an EBER-expressing plasmid, pESK10. The EBER-expressing NP69 cells attained a higher growth rate compared to cells transfected with control plasmid (pcDNA3). However, the EBER-expressing NP69 cells did not form colonies in soft agar and were non-tumorigenic in nude mice. To investigate if EBERs may protect the nasopharyngeal epithelial cells from apoptotic insults, we treated the EBER-expressing NP69 cells with a dsRNA analogue, poly(I).poly(C) (pIC), to activate PKR in cells and examined for their responses. Lower level of PKR phosphorylation and elevation of Bcl-2 were observed in EBER-expressing NP69 cells. In addition, other apoptotic markers including the cleaved forms of caspase-3 and poly(ADP)ribose polymerase (PARP) were found to be lower in EBER-expressing NP69 cells after treatment with pIC. Lower phosphorylation levels of p38 MAPK (mitogen-activated protein kinase) and c-jun were also observed in EBER-expressing NP cells. Our results suggest that EBER expression may confer an apoptotic-resistant phenotype in immortalized nasopharyngeal epithelial cells.
机译：爱泼斯坦巴尔病毒（EBV）感染与鼻咽癌（NPC）的发展密切相关。 EBV编码的RNA（EBER）是EBV感染细胞中最丰富的EBV转录本（每个细胞约10（7）拷贝）。但是，EBER表达的细胞功能，尤其是在鼻咽上皮细胞中，仍然知之甚少。 EBER具有类似于双链RNA（dsRNA）的二级结构，并且可能与双链RNA依赖性蛋白激酶（PKR）结合并干扰其功能。 PKR的激活涉及自磷酸化，导致蛋白合成抑制和细胞凋亡。通过激活PKR诱导细胞凋亡可能是被病毒感染的细胞采用的抗病毒应答。我们已经检查了永生的鼻咽上皮细胞系（NP69）中EBER表达的功能特性。通过用表达EBER的质粒pESK10转染NP69细胞来实现EBER的表达。与转染了对照质粒（pcDNA3）的细胞相比，表达EBER的NP69细胞获得了更高的生长速率。但是，表达EBER的NP69细胞在软琼脂中不形成菌落，并且在裸鼠中没有致瘤性。为了研究EBER是否可以保护鼻咽上皮细胞免受凋亡损害，我们用dsRNA类似物poly（I）.poly（C）（pIC）处理了表达EBER的NP69细胞，以激活细胞中的PKR并检查其反应。在表达EBER的NP69细胞中观察到较低的PKR磷酸化水平和Bcl-2的升高。此外，在用pIC处理后，在表达EBER的NP69细胞中发现其他凋亡标记物，包括caspase-3的切割形式和聚（ADP）核糖聚合酶（PARP）较低。在表达EBER的NP细胞中也观察到p38 MAPK（促分裂原激活的蛋白激酶）和c-jun的磷酸化水平较低。我们的结果表明，EBER表达可能在永生化的鼻咽上皮细胞中赋予抗凋亡的表型。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号