And suppression of cell growthTo investigate whether NSC-741909-mediated ROS generationAnd suppression of cell growthTo investigate

And suppression of cell growthTo investigate whether NSC-741909-mediated ROS generation
And suppression of cell growthTo investigate whether NSC-741909-mediated ROS generation was correlated with NSC-741909-mediated cell growth suppression, we measured cell viability and ROS generation after NSC-741909 treatment in two sensitive (H460 and H157) and two resistant (H322, H1299) lung cancer cell lines. Normal bronchial epithelial cells (HBEC), which is resistant to NSC-741909, were alsoincluded in the studies. The cells were treated with 0.03 10 M NSC-741909 for 24 h and then cell viability was determined by using the SRB assay. To test for the generation of ROS, the cells were treated with 1 M NSC741909 for 6 h and then stained with H2DCF-DA, as described buy Lixisenatide earlier. The results showed that treatment with NSC-741909 markedly suppressed cell growth PubMed ID: in a dosedependent manner in both the H460 and H157 cells, with a 50 growth-inhibitory concentration of 0.2 M and 0.1 M respectively. In comparison, H322, H1299 and HBEC were resistant to NSC-741909, with a 50 growth-inhibitory concentration of more than 10 M, the highest concentration tested (Fig. 2A). The NSC-741909-induced ROS production paralleled the results of the cell viability experiment; ROS generation increased markedly after exposure of H460 and H157 cells to NSC-741909 (1 M) for 6 h as compared with the solvent-treated controls (data not shown). In contrast, we did not detect any ROS in H322 and H1299 cells 6 h after NSC-741909 treatment, even at a concentration of 10 M, although a mild ROS increase (<0.6 fold) was observed in HBEC under the same treatment (Fig. 2B). These data show that the increased ROS production coincides with the suppression of cell growth after NSC-741909 treatment.Antioxidant blocks NSC-741909-induced ROS production and suppression of cell growthROS, such as hydrogen peroxide (H2O2), superoxide (O2), and hydroxyl radical (OH?, are generated in cells byWei et al. Journal of Translational Medicine 2010, 8:37 5 ofFigure 2 Antitumor cell activity of NSC-741909 is associated with ROS generation. (A) Two sensitive (H460 and H157 cells) and two resistant lung cancer cell lines (H322 and H1299) were treated with different concentrations of NSC-741909 (0.03 - 10 M). Cell viability was determined 24 h after treatment. Cells treated with solvent (dimethylsulfoxide) alone were used as controls, and their viability was set to 100 . Each data point represents the mean ?SD of three independent experiments. (B) The five cell lines were treated with 1 M NSC-741909 for 6 h and then stained with 2', 7'dichlorofluorescein diacetate. Fluorescence intensity in cell samples was determined by flow cytometry analysis. Shown here are representative FACS graphs, which show the shift in the fluorescent cell population after NSC-741909 treatment (dark lines) when compared with control cells (light lines).several pathways. Most cellular O2- is generated during electron transport through the mitochondrial respiratory chain reactions mediated by the coenzyme Q and ubiquinone complexes. O2- is also generated by NADPH cytochrome P450 reductase, hypoxanthine/xanthine oxidase, NADPH oxidase, lipoxygenase (LOX), and cyclooxygenase [17]. Superoxide dismutase converts O2- into H2O2, and H2O2 is mostly converted into H2O by glutathione (GSH) peroxidase and catalase. H2O2 produces the highly reactive OH?by the Fenton/Haber-Weiss reaction in the presence of iron [17]. To further examine the role of the ROS generated by treatment of c.