Overexpression of Telomerase Protects Human and Murine Lung Epithelial Cells from Fas- and Bleomycin-Induced Apoptosis via FLIP Upregulation.
Overexpression of Telomerase Protects Human and Murine Lung Epithelial Cells from Fas- and Bleomycin-Induced Apoptosis via FLIP Upregulation.
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DOI：
10.1371/journal.pone.0126730
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发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Wallach-Dayan SB
中科院分区：
文献类型：
--
作者：
Arish N;Cohen PY;Golan-Gerstl R;Fridlender Z;Dayan MR;Zisman P;Breuer R;Wallach-Dayan SB
给患有淋巴瘤和其他肿瘤的患者施用高剂量的博来霉素通常会导致显着的肺毒性，特别是导致上皮细胞凋亡。肺泡上皮细胞凋亡是博莱霉素诱导的肺纤维化发病机制中的重要一步。 Fas-FasL 途径是主要的细胞凋亡途径之一。端粒酶是一种核糖核蛋白RNA依赖性DNA聚合酶复合物，由RNA模板和催化蛋白端粒酶逆转录酶(TERT)组成。端粒酶还具有端粒外作用，包括调节抗凋亡基因的转录、分化信号等。我们假设端粒酶过度表达通过端粒外作用（例如调节抗凋亡基因，特别是 FLICE 样抑制蛋白（FLIP））影响 Fas 诱导的上皮细胞凋亡。通过使用 cDNA hTERT 表达载体瞬时转染，小鼠 (MLE) 和人 (A549) 肺上皮细胞系中的端粒酶上调。使用基于实时 PCR 的系统检测端粒酶活性。通过膜联蛋白 V 染色、FACS 分析和共聚焦显微镜评估用抗 Fas 激活 mAb 或对照 IgG 处理后博莱霉素和博莱霉素诱导的 Fas 介导的细胞凋亡；通过蛋白质印迹检测半胱天冬酶裂解；通过蛋白质印迹和流式细胞术检测 FLIP 或 Fas 分子。肺上皮细胞的 hTERT 转染导致其端粒酶活性增加 100%。在所有实验中，与对照组相比，hTERT 转染细胞中 Fas 诱导的肺上皮细胞凋亡显着减少。端粒酶活性增加的肺上皮细胞的FLIP表达水平较高，但膜Fas表达没有变化。人肺上皮细胞中 hTERT+ 的上调以及随后 shFLIP-RNA 对 FLIP 的下调消除了 hTERT 介导的细胞凋亡抵抗。端粒酶介导的 FLIP 过表达可能是一种新机制，可以保护暴露于博来霉素的人肺上皮细胞免于凋亡。
High doses of bleomycin administered to patients with lymphomas and other tumors lead to significant lung toxicity in general, and to apoptosis of epithelial cells, in particular. Apoptosis of alveolar epithelium is an important step in the pathogenesis of bleomycin-induced pulmonary fibrosis. The Fas-FasL pathway is one of the main apoptotic pathways involved. Telomerase is a ribonucleoprotein RNA-dependent DNA polymerase complex consisting of an RNA template and a catalytic protein, telomerase reverse transcriptase (TERT). Telomerase also possess extra-telomeric roles, including modulation of transcription of anti-apoptotic genes, differentiation signals, and more. We hypothesized that telomerase overexpression affects Fas-induced epithelial cell apoptosis by an extra-telomeric role such as regulation of anti-apoptotic genes, specifically FLICE-like inhibitory protein (FLIP). Telomerase in mouse (MLE) and human (A549) lung epithelial cell lines was upregulated by transient transfection using cDNA hTERT expression vector. Telomerase activity was detected using a real-time PCR-based system. Bleomycin, and bleomycin-induced Fas-mediated apoptosis following treatment with anti-Fas activating mAb or control IgG, were assessed by Annexin V staining, FACS analysis, and confocal microscopy; caspase cleavage by Western blot; FLIP or Fas molecule detection by Western blot and flow cytometry. hTERT transfection of lung epithelial cells resulted in a 100% increase in their telomerase activity. Fas-induced lung epithelial cell apoptosis was significantly reduced in hTERT-transfected cells compared to controls in all experiments. Lung epithelial cells with increased telomerase activity had higher levels of FLIP expression but membrane Fas expression was unchanged. Upregulation of hTERT+ in human lung epithelial cells and subsequent downregulation of FLIP by shFLIP-RNA annulled hTERT-mediated resistance to apoptosis. Telomerase-mediated FLIP overexpression may be a novel mechanism to confer protection from apoptosis in bleomycin-exposed human lung epithelial cells.
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一种新型的端粒酶激活剂在特发性肺纤维化的鼠模型中抑制肺损伤。
影响因子：
3.7
作者：
Le Saux CJ;Davy P;Brampton C;Ahuja SS;Fauce S;Shivshankar P;Nguyen H;Ramaseshan M;Tressler R;Pirot Z;Harley CB;Allsopp R
通讯作者：
Allsopp R
影响因子：
24.3
作者：
Fridlender, Z. G.;Cohen, P. Y.;Breuer, R.
通讯作者：
Breuer, R.
DOI：
10.1165/rcmb.2005-0252oc
发表时间：
2006-05-01
影响因子：
6.4
作者：
Liu, T;Hu, B;Phan, SH
通讯作者：
Phan, SH
影响因子：
1.7
作者：
Degryse AL;Xu XC;Newman JL;Mitchell DB;Tanjore H;Polosukhin VV;Jones BR;McMahon FB;Gleaves LA;Phillips JA 3rd;Cogan JD;Blackwell TS;Lawson WE
通讯作者：
Lawson WE
DOI：
10.1165/ajrcmb.16.1.8998084
发表时间：
1997-01-01
影响因子：
6.4
作者：
Hagimoto, N;Kuwano, K;Hara, N
通讯作者：
Hara, N