Selective unresponsiveness to the inhibition of p38 MAPK activation by cAMP helps L929 fibroblastoma cells escape TNF-alpha-induced cell death.
Selective unresponsiveness to the inhibition of p38 MAPK activation by cAMP helps L929 fibroblastoma cells escape TNF-alpha-induced cell death.
复制标题
DOI：
10.1186/1476-4598-9-6
复制
发表时间：
2010-01-13
期刊：
影响因子：
37.3
通讯作者：
Shen B
中科院分区：
文献类型：
--
作者：
Wang J;Tang R;Lv M;Zhang J;Shen B
环腺苷酸（cAMP）信号通路已被报道促进或抑制细胞死亡，在细胞环境依赖性的方式。我们的前期研究表明，cAMP反应元件结合蛋白（CREB）诱导动力蛋白轻链（DLC）的表达是cAMP抑制成纤维细胞丝裂原活化蛋白激酶（MAPK）p38活化的必要条件，从而抑制NF-κB活性，促进肿瘤坏死因子-α（TNF-α）诱导的细胞死亡。然而，目前尚不清楚这一规定是否也适用于成纤维细胞瘤细胞。在用各种cAMP升高剂处理细胞后，在L929成纤维细胞瘤细胞中测定细胞内cAMP。通过碘化丙啶（PI）染色和随后的流式细胞术测量在存在或不存在RNA合成抑制剂放线菌素D或针对CREB的小干扰RNA（siRNAs）的情况下，cAMP对TNF-α诱导的L929细胞细胞死亡的影响。用免疫印迹法分析p38和MAPK超家族的另一成员c-Jun N-末端蛋白激酶（JNK）的活化。JNK选择性抑制剂D-JNKi 1和p38选择性抑制剂SB 203580被用来检测JNK和p38在这个过程中的作用。通过免疫印迹分析DLC或cAMP的其他介质的表达。在转染标记GFP的DLC异位表达后，通过PI染色和随后的流式细胞术测量cAMP对GFP+细胞中TNF-α诱导的细胞死亡的影响。cAMP升高通过CREB介导的转录抑制TNF-α诱导的L929成纤维细胞瘤细胞的坏死性细胞死亡。cAMP的促生存作用与L929细胞对cAMP抑制p38激活的选择性无反应性有关，即使cAMP在相同条件下显著抑制JNK的激活。进一步的研究表明，在L929细胞中，cAMP抑制p38的主要介质DLC的诱导受损。用p38特异性抑制剂或DLC异位表达抑制p38的活化，可逆转cAMP对TNF-α诱导的L929细胞死亡的保护作用。这些数据表明，肿瘤细胞中缺乏促凋亡途径导致cAMP的净存活效应。
The cyclic AMP (cAMP) signaling pathway has been reported to either promote or suppress cell death, in a cell context-dependent manner. Our previous study has shown that the induction of dynein light chain (DLC) by cAMP response element-binding protein (CREB) is required for cAMP-mediated inhibition of mitogen-activated protein kinase (MAPK) p38 activation in fibroblasts, which leads to suppression of NF-κB activity and promotion of tumor necrosis factor-α (TNF-α)-induced cell death. However, it remains unknown whether this regulation is also applicable to fibroblastoma cells. Intracellular cAMP was determined in L929 fibroblastoma cells after treatment of the cells with various cAMP elevation agents. Effects of cAMP in the presence or absence of the RNA synthesis inhibitor actinomycin D or small interfering RNAs (siRNAs) against CREB on TNF-α-induced cell death in L929 cells were measured by propidium iodide (PI) staining and subsequent flow cytomety. The activation of p38 and c-Jun N-terminal protein kinase (JNK), another member of MAPK superfamily, was analyzed by immunoblotting. JNK selective inhibitor D-JNKi1 and p38 selective inhibitor SB203580 were included to examine the roles of JNK and p38 in this process. The expression of DLC or other mediators of cAMP was analyzed by immunoblotting. After ectopic expression of DLC with a transfection marker GFP, effects of cAMP on TNF-α-induced cell death in GFP+ cells were measured by PI staining and subsequent flow cytomety. Elevation of cAMP suppressed TNF-α-induced necrotic cell death in L929 fibroblastoma cells via CREB-mediated transcription. The pro-survival role of cAMP was associated with selective unresponsiveness of L929 cells to the inhibition of p38 activation by cAMP, even though cAMP significantly inhibited the activation of JNK under the same conditions. Further exploration revealed that the induction of DLC, the major mediator of p38 inhibition by cAMP, was impaired in L929 cells. Enforced inhibition of p38 activation by using p38 specific inhibitor or ectopic expression of DLC reversed the protection of L929 cells by cAMP from TNF-α-induced cell death. These data suggest that the lack of a pro-apoptotic pathway in tumor cells leads to a net survival effect of cAMP.
登录
查看更多内容
DOI：
10.1111/j.1749-6632.2002.tb04327.x
发表时间：
2002-01-01
期刊：
PROTEIN KINASE A AND HUMAN DISEASE
影响因子：
--
作者：
Rosenberg, D;Groussin, L;Bertherat, J
通讯作者：
Bertherat, J
影响因子：
56.9
作者：
HAN, J;LEE, JD;ULEVITCH, RJ
通讯作者：
ULEVITCH, RJ
影响因子：
64.5
作者：
ROUSE, J;COHEN, P;NEBREDA, AR
通讯作者：
NEBREDA, AR
DOI：
10.4049/jimmunol.0900801
发表时间：
2009-07-15
期刊：
Journal of immunology (Baltimore, Md. : 1950)
影响因子：
--
作者：
Kunisch E;Jansen A;Kojima F;Löffler I;Kapoor M;Kawai S;Rubio I;Crofford LJ;Kinne RW
通讯作者：
Kinne RW
影响因子：
4.8
作者：
Nishihara, H;Hwang, M;Insel, PA
通讯作者：
Insel, PA