Su Jung-Chen, Lin Kuei-Li, Chien Ching-Ming, Lu Chih-Ming, Chen Yeh-Long, Chang Long-Sen, Lin Shinne-Ren
Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 807, Taiwan, ROC.
Life Sci. 2009 Sep 23;85(13-14):505-16. doi: 10.1016/j.lfs.2009.08.006. Epub 2009 Aug 21.
This study was performed to elucidate whether mitogen-activated protein kinases (MAPKs) are involved in the modulation of apoptosis and cell-cycle arrest by N'-(11H-indolo[3,2-c]quinolin-6-yl)-N,N-dimethylethane-1,2-diamine (IQDMA), in human lung adenocarcinoma A549 cells.
The effect of IQDMA on cell-cycle arrest and apoptosis was measured by flow cytometry, and phosphorylation levels of mitogen-activated protein kinases (MAPKs) and its regulatory molecules were studied by immunoblots.
IQDMA-induced G(2)/M arrest was associated with a marked decrease in the protein expressions of cyclin A, cyclin B, and cyclin-dependent kinase (Cdk)1. IQDMA-induced apoptosis was accompanied with up-regulation of the protein expression of Bax and down-regulation of the protein levels of Bcl-2, Mcl-1, X-linked inhibitor of apoptosis (XIAP), and survivin, resulting in cytochrome c release and sequential activation of caspase-9 and caspase-3. IQDMA activated c-Jun N-terminal kinase (JNK), p38 MAPK (p38) and extracellular signal-regulated kinase (ERK) on A549 cells in a time-dependent manner. Unlike the ERK inhibitor (PD98059), inhibitors of JNK (SP600125) and p38 MAPK (SB203580) suppressed IQDMA-induced apoptosis and G(2)/M phase arrest in A549 cells. Both SP600125 and SB203580 attenuated the activation of Bax and cytochrome c release, and reversed down-regulation of Bcl-2, XIAP, survivin, cyclin A, cyclin B, and Cdk1 in IQDMA-treated cells.
These findings indicate that JNK/p38 MAPK pathways play an important role in IQDMA-induced G(2)/M arrest and apoptosis of A549 cells.
本研究旨在阐明丝裂原活化蛋白激酶（MAPKs）是否参与N'-(11H-吲哚并[3,2-c]喹啉-6-基)-N,N-二甲基乙烷-1,2-二胺（IQDMA）对人肺腺癌A549细胞凋亡和细胞周期阻滞的调节作用。
采用流式细胞术检测IQDMA对细胞周期阻滞和凋亡的影响，通过免疫印迹研究丝裂原活化蛋白激酶（MAPKs）及其调节分子的磷酸化水平。
IQDMA诱导的G(2)/M期阻滞与细胞周期蛋白A、细胞周期蛋白B和细胞周期蛋白依赖性激酶（Cdk）1的蛋白表达显著降低有关。IQDMA诱导的凋亡伴随着Bax蛋白表达上调以及Bcl-2、Mcl-1、X连锁凋亡抑制蛋白（XIAP）和生存素蛋白水平下调，导致细胞色素c释放以及半胱天冬酶-9和半胱天冬酶-3的顺序激活。IQDMA以时间依赖性方式激活A549细胞中的c-Jun氨基末端激酶（JNK）、p38丝裂原活化蛋白激酶（p38）和细胞外信号调节激酶（ERK）。与ERK抑制剂（PD98059）不同，JNK抑制剂（SP600125）和p38丝裂原活化蛋白激酶抑制剂（SB203580）可抑制IQDMA诱导的A549细胞凋亡和G(2)/M期阻滞。SP600125和SB203580均减弱了Bax的激活和细胞色素c的释放，并逆转了IQDMA处理细胞中Bcl-2、XIAP、生存素、细胞周期蛋白A、细胞周期蛋白B和Cdk1的下调。
这些发现表明JNK/p38 MAPK通路在IQDMA诱导的A549细胞G(2)/M期阻滞和凋亡中起重要作用。
