• Tuberculosis and Respiratory Diseases
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• v.52 no.5
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• pp.485-496
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• 2002

Background : The NF-${\kappa}B$ transcription factors control various biological processes including the immune response, acute phase reaction and cell cycle regulation. NF-${\kappa}B$ complexes are retained in the cytoplasm in the basal state and various stimuli cause a translocation of the NF-${\kappa}B$ complexes into the nucleus where they bind to the ${\kappa}B$ elements and regulate the transcription of the target genes. Recent reports also suggest that NF-${\kappa}B$ proteins are involved in oncogenesis, tumor growth and metastasis. High expression of NF-${\kappa}B$ expression was reported in many cancer cell lines and tissues. The constitutive activation of NF-${\kappa}B$ was also reported in several cancer cell lines supporting its role in cancer development and survival. The anti-apoptotic action of NF-${\kappa}B$ is important for cancer survival. NF-${\kappa}B$ also controls the expression of several proteins that are important for cellular adhesion (ICAM-1, VCAM-1) suggesting a role in cancer metastasis. In lung cancer, high expression levels of the NF-${\kappa}B$ subunit p50 and c-Rel were reported. In fact, high expression does not mean a high activity, and the activation pattern of NF-${\kappa}B$ in lung cancer has not been reported. Materials and Methods : In this study, the NF-${\kappa}B$ nuclear binding activity in the basal and TNF-${\alpha}$ stimulated states were exmined in various lung cancer cell lines and compared with the normal bronchial epithelial cell line. Twelve lung cancer cell lines including the non-small cell and small cell lung cancer cell lines (A549, NCI-H358, NCI-H441, NCI-H552, NCI-H2009, NCI-H460, NCI-H1229, NCI-H1703, NCI-H157, NCI-H187, NCI-H417, NCI-H526) and BEAS-2B bronchial epithelial cell line were used. To evaluate the NF-${\kappa}B$ expression and DNA binding activity, western blot analysis and an electrophoretic mobility shift assay with the nuclear protein extracts. Results : The basal expressions of the p65 and p50 subunits were observed in the BEAS-2B cell line and all lung cancer cell lines except for NCI-H358 and NCI-H460. The expression levels of p65 and p50 were increased 30 minutes after stimulation with TNF-${\alpha}$ in BEAS-2B and in 10 lung cancer cell lines. In the NCI-H358 and NCI-H460 cell lines, p65 expression was not observed in the basal and stimulated states and the two p50 related protein levels were higher after stimulation with TNF-${\alpha}$ These new proteins were smaller than p50 and are thought to be variants of p50. In the basal state, NF-${\kappa}B$ was nearly activated in the BEAS-2B and all lung cancer cell lines. The DNA binding activity of the NF-${\kappa}B$ complexes was markedly higher after stimulation with TNF-${\alpha}$ In the BEAS-2B and all lung cancer cell line except for NCI-H358 and NCI-H460, the activated NF-${\kappa}B$ complex was a p65/p50 heterodimer. In the NCI-H358 and NCI-H460 lung cancer cell lines, the NF-${\kappa}B$ complex was variant of a p50/p50 homodimer. Conclusion : The NF-${\kappa}B$ activation pattern in the lung cancer cell lines and the normal bronchial epithelial cell lines was similar except for the activation of a variant of the p50/p50 homodimer in some lung cancer cell linse.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.846-860
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• 1998

Background: Endotoxin (LPS : lipopolysaccharide), a potent activator of immune system, can induce acute and chronic inflammation through the production of cytokines by a variety of cells, such as monocytes, endothelial cells, lymphocytes, eosinophils, neutrophils and fibroblasts. LPS stimulate the mononucelar cells by two different pathway, the CD14 dependent and independent way, of which the former has been well documented, but not the latter. LPS binds to the LPS-binding protein (LBP), in serum, to make the LPS-LBP complex which interacts with CD14 molecules on the mononuclear cell surface in peripheral blood or is transported to the tissues. In case of high concentration of LPS, LPS can stimulate directly the macrophages without LBP. We investigated to detect the generation of proinflammatory cytokines such as interleukin 1 (IL-1), IL-6 and TNF-$\alpha$ and fibrogenic cytokine, TGF-$\beta$, by peripheral blood mononuclear cells (PBMC) after LPS stimulation under serum-free conditions, which lacks LBPs. Methods : PBMC were obtained by centrifugation on Ficoll Hypaque solution of peripheral venous bloods from healthy normal subjects, then stimulated in the presence of LPS (0.1 ${\mu}g/mL$ to 100 ${\mu}g/mL$ ). The activities of IL-1, IL-6, TNF, and TGF-$\beta$ were measured by bioassaies using cytokines - dependent proliferating or inhibiting cell lines. The cellular sources producing the cytokines was investigated by immunohistochemical stains and in situ hybridization. Results : PBMC started to produce IL-6, TNF-$\alpha$ and TGF-$\beta$ in 1 hr, 4 hrs and 8hrs, respectively, after LPS stimulation. The production of IL-6, TNF-$\alpha$ and TGF-$\beta$ continuously increased 96 hrs after stimulation of LPS. The amount of production was 19.8 ng/ml of IL-6 by $10^5$ PBMC, 4.1 ng/mL of TNF by $10^6$ PBMC and 34.4 pg/mL of TGF-$\beta$ by $2{\times}10^6$ PBMC. The immunoreactivity to IL-6, TNF-$\alpha$ and TGF-$\beta$ were detected on monocytes in LPS-stimulated PBMC. Some of lymphocytes showed positive immunoreactivity to TGF-$\beta$. Double immunohistochemical stain showed that IL-1$\beta$, IL-6, TNF-$\alpha$ expression was not associated with CD14 postivity on monocytes. IL-1$\beta$, IL-6, TNF-$\alpha$ and TGF-$\beta$mRNA expression were same as observed in immunoreactivity for each cytokines. Conclusion: When monocytes are stimulated with LPS under serum-free conditions, IL-6 and TNF-$\alpha$ are secreted in early stage of inflammation. In contrast, the secretion of TGF-$\beta$ arise in the late stages and that is maintained after 96 hrs. The main cells releasing IL-1$\beta$, IL-6, TNF-$\alpha$ and TGF-$\beta$ are monocytes, but also lymphocytes can secret TGF-$\beta$.