• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1265-1276
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• 1998

Background : Nitric oxide(NO) is an endogenously produced free radical that plays an important role in regulating vascular tone, inhibition of platelet aggregation and white blood cell adhesion to endothelial cells, and host defense against infection. The highly reactive nature of NO with oxygen radicals suggests that it may either promote or reduce oxidant-induced cell injury in several biological pathways. Oxidant injury and interactions between pulmonary vascular endothelium and leukocytes are important in the pathogenesis of acute lung injury, including acute respiratory distress syndrome(ARDS). In ARDS, therapeutic administration of NO is a clinical condition providing exogenous NO in oxidant-induced endothelial injury. The role of exogenous NO from NO donor or the suppression of endogenous NO production was evaluated in oxidant-induced endothelial injury. Method : The oxidant injury in cultured rat lung microvascular endothelial cells(RLMVC) was induced by hydrogen peroxide generated from glucose oxidase(GO). Cell injury was evaluated by $^{51}$chromium($^{51}Cr$) release technique. NO donor, such as S-nitroso-N-acetylpenicillamine(SNAP) or sodium nitroprusside(SNP), was added to the endothelial cells as a source of exogenous NO. Endogenous production of NO was suppressed with N-monomethyl-L-arginine(L-NMMA) which is an NO synthase inhibitor. L-NMMA was also used in increased endogenous NO production induced by combined stimulation with interferon-$\gamma$(INF-$\gamma$), tumor necrosis factor-$\alpha$(TNF-$\alpha$), and lipopolysaccharide(LPS). NO generation from NO donor or from the endothelial cells was evaluated by measuring nitrite concentration. Result : $^{51}Cr$ release was $8.7{\pm}0.5%$ in GO 5 mU/ml, $14.4{\pm}2.9%$ in GO 10 mU/ml, $32.3{\pm}2.9%$ in GO 15 mU/ml, $55.5{\pm}0.3%$ in GO 20 mU/ml and $67.8{\pm}0.9%$ in GO 30 mU/ml ; it was significantly increased in GO 15 mU/ml or higher concentrations when compared with $9.6{\pm}0.7%$ in control(p < 0.05; n=6). L-NMMA(0.5 mM) did not affect the $^{51}Cr$ release by GO. Nitrite concentration was increased to $3.9{\pm}0.3\;{\mu}M$ in culture media of RLMVC treated with INF-$\gamma$ (500 U/ml), TNF-$\alpha$(150 U/ml) and LPS($1\;{\mu}g/ml$) for 24 hours ; it was significantly suppressed by the addition of L-NMMA. The presence of L-NMMA did not affect $^{51}Cr$ release induced by GO in RLMVC pretreated with INF-$\gamma$, TNF-$\alpha$ and LPS. The increase of $^{51}Cr$ release with GO(20 mU/ml) was prevented completely by adding 100 ${\mu}M$ SNAP. But the add of SNP, potassium ferrocyanate or potassium ferricyanate did not protect the oxidant injury. Nitrite accumulation was $23{\pm}1.0\;{\mu}M$ from 100 ${\mu}M$ SNAP at 4 hours in phenol red free Hanks' balanced salt solution. But nitrite was not detectable from SNP upto 1 mM The presence of SNAP did not affect the time dependent generation of hydrogen peroxide by GO in phenol red free Hanks' balanced salt solution. Conclusion : Hydrogen peroxide generated by GO causes oxidant injury in RLMVC. Exogenous NO from NO donor prevents oxidant injury, and the protective effect may be related to the ability to release NO. These results suggest that the exogenous NO may be protective on oxidant injury to the endothelium.

• Tuberculosis and Respiratory Diseases
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• v.41 no.4
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• pp.339-353
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• 1994

Background : The p53 gene codes for a DNA-binding nuclear phosphoprotein that appears to inhibit the progression of cells from the G1 to the S phase of the cell cycle. Mutations of the p53 gene are common in a wide variety of human cancers, including lung cancer. In lung cancers, point mutations of the p53 gene have been found in all histological types including approximately 45% of resected NSCLC and even more frequently in SCLC specimens. Mutant forms of the p53 protein have transforming activity and interfere with the cell-cycle regulatory function of the wild-type protein. The majority of p53 gene mutations produce proteins with altered conformation and prolonged half life; these mutant proteins accumulate in the cell nucleus and can be detected by immunohistochemical staining. But protein overexpression has been reported in the absence of mutation. p53 protein overexpression or gene mutation is reported poor prognostic factor in breast cancer, but in lung cancer, its prognostic significance is controversial. Method : We investigated the p53 abnormalities by nucleotide sequencing, polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP), and immunohistochemical staining. We correlated these results with each other and survival in 75 patients with NSCLC resected with curative intent. Overexpression of the p53 protein was studied immunohistochemically in archival paraffin- embedded tumor samples using the D07(Novocastra, U.K.) antibody. Overexpression of p53 protein was defined by the nuclear staining of greater than 25% immunopositive cells in tumors. Detection of p53 gene mutation was done by PCR-SSCP and nucleotide sequencing from the exon 5-9 of p53 gene. Result: 1) Of the 75 patients, 36%(27/75) showed p53 overexpression by immunohistochemical stain. There was no survival difference between positive and negative p53 immunostaining(overall median survival of 26 months, disease free median survival of 13 months in both groups). 2) By PCR-SSCP, 27.6%(16/58) of the patients showed mobility shift. There was no significant difference in survival according to mobility shift(overall median survival of 27 in patients without mobility shift vs 20 months in patients with mobility shift, disease free median survival of 8 months vs 10 months respectively). 3) Nucleotide sequence was analysed from 29 patients, and 34.5%(10/29) had mutant p53 sequence. Patients with the presence of gene mutations showed tendency to shortened survival compared with the patients with no mutation(overall median survival of 22 vs 27 months, disease free median survival of 10 vs 20 months), but there was no statistical significance. 4) The sensitivity and specificity of immunostain based on PCR-SSCP was 67.0%, 74.0%, and that of the PCR-SSCP based on the nucleotide sequencing was 91.8%, 96.2% respectively. The concordance rate between the immunostain and PCR-SSCP was 62.5%, and the rate between the PCR-SSCP and nucleotide sequencing was 95.3%. Conclusion : In terms of detection of p53 gene mutation, PCR-SSCP was superior to immunostaining. p53 gene abnormalities either overexpression or mutation were not a significant prognostic factor in NSCLC patients resected with curative intent. However, patients with the mutated p53 gene showed the trends of early relapse.

• Tuberculosis and Respiratory Diseases
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• v.42 no.6
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• pp.846-854
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• 1995

Background: Cytokeratin 19 is a subunit of cytokeratin intermediate filament expressed in simple epithelia such as respiratory epithelial cells and their malignant counterparts. An immunoradiometric assay is available to detect a fragment of the cytokeratin, referred to as Cyfra 21-1 in the serum. This study was conducted to evaluate the clinical utility of this new marker in the diagnosis of lung cancer compared with established markers of squamous cell carcinoma antigen (SCC Ag) and carcino-embryonic antigen(CEA). In addition, we compared the diagnostic sensitivity and specificity of Cyfra 21-1 with those of SCC Ag in squamous cell carcinoma of the lung. We also measured the level of Cyfra 21-1 in the different stages of squamous cell carcinoma of the lung. Method: We measured Cyfra 21-1(ELSA-CYFRA 21-1), SCC Ag(ABBOTT SCC RIABEAD) and CEA(ELSA2-CEA) in 79 patients with primary lung cancer and in 78 persons as a comparison group including 32 patients with pulmonary tuberculosis, 23 patients with benign lung disease and 23 cases with healthy individual. Cyfra 21-1 is measured by a solid-phase immunoradiometric assay(CIS Bio International, France) based on the two-site sandwich method. SCC Ag is measured by a radioimmunoassay(Abbott Laboratories, USA). CEA is measured by a immunoradiometric assay(CIS Bio International, France). All data were expressed as the mean$\pm$standard deviation. Results: 1) The mean value of Cyfra 21-1 was $18.38{\pm}3.65\;ng/mL$ in the lung cancer and $1.l6{\pm}0.53\;ng/mL$ in the comparison group(p<0.0001). SCC Ag was $3.53{\pm}6.06\;ng/mL$ in the lung cancer and $1.19{\pm}0.5\;ng/mL$ in the comparison group(p<0.01). CEA was $35.03{\pm}13.9\;ng/mL$ in the lung cancer and $2.89{\pm}1.01\;ng/mL$ in the comparison group(p<0.0001). 2) Cyfra 21-1 level in squamous cell carcinoma($31.52{\pm}40.13\;ng/mL$) was higher than that in adenocarcinoma($2.41{\pm}1.34\;ng/mL$)(p<0.0001) and small cell carcinoma($2.15{\pm}2.05\;ng/mL$)(p=0.007). SCC Ag level in squamous cell carcinoma($5.1{\pm}7.68\;ng/mL$) was higher than that in adenocarcinoma($1.36{\pm}0.69\;ng/mL$)(p=0.009) and small cell carcinoma($1.1{\pm}0.24\;ng/mL$) (p=0.024). 3) The level of Cyfra 21-1 was not correlated with the progression of stage in squamous cell carcinoma of the lung. 4) Using the cut-off value of 3.3ng/mL, the diagnostic sensitivity of Cyfra 21-1 was 83% in squamous cell carcinoma, 22% in adenocarcinoma and 17% in small cell carcinoma. The sensitivity of SCC Ag and CEA were 39% and 20%, respectively in squamous cell carcinoma, 11% and 39% in adenocarcinoma, and 0% and 33% in small cell carcinoma. 5) Comparison of the receiver operating characteristics curves(ROC curve) for Cyfra 21-1, SCC Ag and CEA revealed that Cyfra 21-1 showed highest diagnostic sensitivity among them in the diagnosis of lung cancer. Conclusion: Cyfra 21-1 is thought to be a better tumor marker for the diagnosis of lung cancer than SCC Ag and CEA, especially in squamous cell carcinoma of the lung.

• 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.