• Tuberculosis and Respiratory Diseases
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• v.57 no.2
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• pp.160-168
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• 2004

Background : The role of second-line chemotherapy in the treatment of advanced non-small cell lung cancer (NSCLC) is known to be limited. Recently, ZD1839, the small molecule epidermal growth factor receptor-tyrosine kinase inhibitor, has been developed and has shown anti-tumor activity in patients with solid malignant tumors including lung cancer. We evaluated the response rate and toxicities of ZD1839 in patients with advanced NSCLC which has progressed after previous chemotherapy. Patients and Methods : We examined 83 patients with advanced NSCLC treated with ZD1839 for more than 1 month in Korea Cancer Center Hospital during the period from January 2002 to September 2003. All the patients were enrolled in the international expanded access program (EAP) with ZD1839 by AstraZeneca. The administered dose of ZD1839 was 250 mg once daily. Chest radiography and laboratory tests were followed-up. We evaluated the response rate, median survival, and toxicity after treatment. Results : Median age of the patients was 59 years (range 33-76). The most predominant cell type was adenocarcinoma and the most stage of the patients was IV. ECOG performance status was as follows; grade 0-1 in 10, grade 2 in 42, and grade 3 in 31 patients. Partial response was achieved in 12 patients (14.5%). Median overall survival was 9.2 (range 1.3-21.6+) months and median time to progression was 3.1 (range 1-21.2+) months. The most common adverse effect of ZD1839 was skin eruption which developed in 25 patients (25.8%). Significantly higher response rate and survival was found in patients with adenocarcinoma or good performance status. Conclusion : ZD1839 showed modest activity and tolerable toxicity in the treatment for patients with NSCLC which has progressed after previous chemotherapy.

• Tuberculosis and Respiratory Diseases
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• v.51 no.2
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• pp.122-134
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• 2001

Background : Some chemotherapeutic drugs induce NF-${\kappa}B$ activation by degrading the $I{\kappa}B{\alpha}$ protein in cancer cells which contributes to anticancer drug resistance. We hypothesized that inhibiting $I{\kappa}B{\alpha}$ degradation would block NF-${\kappa}B$ activation and result in increased tumor cell mortality in response to chemotherapy. Methods : The "superrepressor" form of the NF-${\kappa}B$ inhibitor was transferred by an adenoviral vector (Ad-$I{\kappa}B{\alpha}$-SR) to the human lung cancer cell lines (NCI H157 and NCI H460). With a MIT assay, the level of sensitization to cisplatin and paclitaxel were measured. To confirm the mechanism, an EMSA and Annexin V assay were performed. Results : EMSA showed that $I{\kappa}B{\alpha}$-SR effectively blocked the NF-${\kappa}B$ activation induced by cisplatin. Transduction with Ad-$I{\kappa}B{\alpha}$-SR resulted in an increased sensitivity of the lung cancer cell lines to cisplatin and paclitaxel by a factor of 2~3 in terms of $IC_{50}$. Annexin-V analysis suggests that this increment in chemosensitivity to cisplatin probably occurs through the induction of apoptosis. Conclusion : The blockade of chemotherapeutics induced NF-${\kappa}B$ activation by inducing Ad-$I{\kappa}B{\alpha}$-SR, increased apoptosis and increasing the chemosensitivity of the lung cancer cell lines tested, subsequently. Gene transfer of $I{\kappa}B{\alpha}$-SR appears to be a new therapeutic strategy of chemosensitization in lung cancer.

• Tuberculosis and Respiratory Diseases
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• v.47 no.5
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• pp.618-628
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• 1999

Background: Cell growth is a balance between cell proliferation and cell death. Insulin-like growth factor-I(IGF-I), which binds IGF-I receptor(IGF-IR), mediates cellular proliferation as a potent mitogen. IGF binding protein-3(IGFBP-3) as a circulating major IGFBP can inhibit or enhance the effects of IGF-I on cellular growth by binding IGFs. Methods: We investigated the expressions of mRNA of IGF-I and IGF-IR by northern blot and phosphorylation of IGF-IR with the treatment of IGF-I by western blot in 3T3 fibroblast cells. The cellular proliferations of 3T3 cells with the treatments of IGF-I were evaluated using $^3H$-thymidine incorporation and MTT assay. Also to observe the effect of IGFBP-3 on cellular proliferation, 3T3 cells were treated with anti-IGFBP-3 and ${\alpha}IR_3$(monoclonal antibody to IGF-IR) alone or in combination. Results: Our results demonstrated that 3T3 cells showed mRNA expressions of IGF-I and IGF-IR and the IGF-I increased phosphorylation of IGF-IR. The treatments of 3T3 cells with IGF-I increased cellular proliferation in 5 % and 1 % seruma-containing media, not in serum-free media. The addition of anti-IGFBP-3 to neutralize IGFBP-3 showed 2-fold increase of cellular proliferation, and also co-incubation of anti-IGFBP-3 and ${\alpha}IR_3$ together showed similar increase of cellular proliferation in 3T3 cells. Interestingly, when the cells were pretreated with ${\alpha}IR_3$ for 4 hr, prior to the simultaneous addition of ${\alpha}IR_3$ and anti-IGFBP-3, anti-IGFBP-3-mediated cellular proliferation was decreased to control level. All of these results suggest that free IGF-I released from IGF-I/IGFBP-3 complex would be involved in the cellular proliferation. Conclusion: IGF-I is a mitogen through the activation of IGF-IR in 3T3 cells, and IGFBP-3 could be a potent inhibitor for IGF-I action by binding IGF-I.

• Tuberculosis and Respiratory Diseases
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• v.55 no.1
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• pp.21-30
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• 2003

Background : Mucin synthesis in airways has been reported to be regulated by the epidermal growth factor receptor (EGFR) system. Epidermal growth factor receptor transactivation was identified as a critical element in G-protein-coupled receptors (GPCRs)-induced mitogenic signaling. EGF receptor transactivation by G-protein-coupled receptors requires metalloproteinase cleavage of proHB-EGF. This study was hypothesized that lipopolysaccharide (LPS)-induced mucin production associates with epidermal growth factor receptor transactivation, and MUC5AC production associates with epidermal growth factor receptor transactivation by G-protein-coupled receptors that regulates by metalloproteinase. Method : MUC5AC mucin production was examined in NCI-H292 cells and MUC5AC protein synthesis was assessed using ELISA. For the evaluation of mechanism of LPS-induced MUC5AC production, $TNF{\alpha}$ was measured using ELISA with or without pretreatment of heterotrimeric G-protein inhibitor, mastoparan. MUC5AC protein was measure with pretreatment of polyclonal $TNF{\alpha}$ antibody or mastoparan on LPS-induced MUC5AC production. For the evaluation of relation of G-protein and MUC5AC production, G-protein stimulant, mastopara-7, or matrix metalloproteinase, ADAM10, was added to NCI-H292 cells. MUC5AC protein was measure with pretreatment of polyclonal EGF antibody on mastoparan-7-induced MUC5AC production. Results : LPS alone did not increase significantly MUC5AC production. LPS with $TNF{\alpha}$ induced dose-dependently MUC5AC production in NCI-H292 cells. LPS increased dose-dependently $TNF{\alpha}$ secretion, which was inhibited by mastoparan. LPS with $TNF{\alpha}$-induced MUC5AC production was inhibited by neutralizing polyclonal $TNF{\alpha}$ antibody, mastoparan or AG 1472. Mastoparan-7 or ADAM10 increased dose-dependently MUC5AC production, which was inhibited by polyclonal neutralizing EGF antibody. Conclusion : In LPS-induced MUC5AC synthesis, LPS causes $TNF{\alpha}$ secretion, which induces EGFR expression. EGFR tyrosine kinase phosphorylation result in MUC5AC production. EGF-R transactivation by G-protein-coupled receptors requires matrix metalloproteinase cleavage of proHB-EGF.

• Tuberculosis and Respiratory Diseases
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• v.58 no.5
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• pp.473-479
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• 2005

Background : Gefitinib targets the epidermal growth factor receptor r(EGFR), and Gefitinib has antitumor activity in patient with non-small cell lung cancer (NSCLC). However, only 10 to 20 percent of patients show a clinical response to this drug, and the molecular mechanisms underlying patient sensitivity to gefitinib are unknown. PTEN (Phosphatase and tensin homolog deleted on chromosome Ten) plays a role for the modulation of the phosphatidylinositol 3-kinase pathway (PI3K), which is involved in cell proliferation and survival, so that it can inhibit cell cycle progression and induce G1 arrest. Therefore, we analyzed the relationship between PTEN expression and gefitinib's responsiveness in patients having advanced non small cell lung cancer that had progressed after previous chemotherapy. Methods : The expression of PTEN was studied by immunohistochemistry in paraffin-embedded tumor blocks that were obtained from 22 patients who had been treated with gefitinib from JAN, 2001 to AUG. 2004. For the evaluation of the relationships between the PTEN expression, the clinical stage and the basal characteristics, those cases that showed the respective antigen expression in >50% of the tumor cells were considered positive. Results : The positive rate of PTEN staining was 55% of the total of 22 patients. There was a significant relationship between the increased expression of PTEN and the response group (p=0.039). However, there was no significant relationship between the expression of PTEN and other clinicopathologic characteristics. Conclusion: The expression of PTEN in patients with advanced non small cell lung cancer that has progressed after previous chemotherapy may play a role in gefitinib's responsiveness.

• Tuberculosis and Respiratory Diseases
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• v.60 no.3
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• pp.304-313
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• 2006

Background : Heme oxygenase-1 (HO-1) is an inducible enzyme that catalyzes the oxidative degradation of heme to form biliverdin, carbon monoxide (CO), and free iron. The current evidence has indicated a critical role of HO-1 in cytoprotection and also in other, more diverse biological functions. It is known that the high expression of HO-1 occurs in various tumors, and that HO-1 has an important role in rapid tumor growth because of its antioxidative and antiapoptotic effects. Therefore, the role of HO-1 was analyzed in human lung cancer cell lines, and especially in the A549 cell line. Material and Methods : Human lung cancer cell lines, i.e., A549, NCI-H23, NCI-H157 and NCI-H460, were used for this study. The expression of HO-1 in the untreated state was defined by Western blotting. ZnPP, which is the specific HO inhibitor we used, and the viability of cells were tested for by conducting MTT assaysy. The HO enzymatic activity, as determined via the bilirubin level, was also indirectly measured. Moreover, the generation of intracellular hydrogen peroxide (H2O2) was monitored fluorimetrically with using a scopoletin-horse radish peroxidase (HRP) assay and 2',7'-dichlorofluorescein diacetate (DCFH-DA). We have also transfected small HO-1 interfering RNA (siRNA) into A549 cells, and the apoptotic effects were evaluated by flow cytometric analysis and Western blotting. Results : The A549 cells had a greater expression of HO-1 than the other cell lines, whereas ZnPP significantly decreased the viability of the A549 cells more than the viability of the other lung cancer cells in a dose-dependant fashion. Consistent with the viability, the HO enzymatic activity also was decreased. Moreover, intracellular H2O2 generation via ZnPP was induced in a dose-dependent manner. Apoptotic events were, then induced in the HO-1 siRNA transfected A549 cells. Conclusion : HO-1 provides new important insights into the possible molecular mechanism of the antitumor therapy in lung cancer.

• Tuberculosis and Respiratory Diseases
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• v.52 no.5
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• pp.441-452
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• 2002

Background : Anti-apoptotic proteins may be involved in tumor development, progression and the response to treatment, Bcl-2 is by far the most studied anti-apoptotic protein. A novel inhibitor of apoptosis, designated survivin, and the heat shock proteins (HSPs) have recently been found in many human cancers. Immunohistochemical methods were used to determine the expression level of survivin, HSP70 and bcl-2 in non-small cell lung cancer (NSCLC) to evaluate their clinical significance. Materials and Methods : Tissue array slides were obtained from 99 surgically resected NSCLCs. Immunohistochemical staining was performed by an immuno-peroxidase technique using an avidin-biotinylated horseradish peroxidase complex. Anti-survivin rabbit polyclonal antibodies, anti-HSP70 mouse monoclonal antibodies and anti-bcl-2 mouse monoclonal antibodies were used as the primary antibodies. Results : Positive staining of survivin was detected in 33.3% of the cases. Survivin positivity is associated with to females and recurrence. A nonstatistically significant trend toward increased survivin expression was observed in non-smokers, and its expression inversely correlated with the number of cigarettes smoked in smokers. HSP70 was detected in 84.8% but this did not correlated with the clinicopathologic characteristics. Bcl-2 was detected in 18.2% and its expression correlated to tumor recurrence. No significant difference in the median survival time was noted in a comparison of all cases with survivin expression and those without. There was no association between HSP70 or bcl-2 expression and survival. Conclusion : Survivin expression was significantly associated with females and tumor recurrence. In addition its expression was inversely associated with the number of cigarettes smoked. However, HSP70 and bcl-2 expression were not associated with the clinical parameters or survival. This suggests that measuring the survivin levels may be useful in identifying patients at high risk for disease recurrence. Therefore, survivin might be a new diagnostic/therapeutic target in cancer.

• Tuberculosis and Respiratory Diseases
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• v.66 no.4
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• pp.280-287
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• 2009

Background: The epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), became an attractive therapeutic option for advanced non-small-cell lung cancer (NSCLC). Several studies suggested that there might be some different efficacy or response predictors between gefitinib and erlotinib. We compared the efficacy and toxicity of gefitinib and erlotinib in Korean patients with advanced NSCLC and evaluated specific predictors of response for both gefitinib and erlotinib. Methods: We collected the clinical information on patients with advanced NSCLC, who were treated with gefitinib or erlotinib at the Ewha Womans University Hospital, between July 2003 and February 2009. Median survival times were calculated using the Kaplan-Meier method. Results: Eighty-six patients (52 gefitinib vs. 34 erlotinib) were enrolled. Patient median age was 64 years; 53 (62%) subjects were male. Out of the 86 patients treated, 83 received response evaluation. Of the 83 patients, 35 achieved a response and 12 experienced stable disease while 36 experienced progressive disease, resulting in a response rate of 42% and a disease control rate of 57%. After a median follow-up of 502 days, the median progression-free and overall survival time was 129 and 259 days, respectively. Comparing patients by treatment (gefitinib vs erlotinib), there were no significant differences in the overall response rate (44% vs. 39%, p=0.678), median survival time (301 days vs. 202 days, p=0.151), or time to progression (136 days vs. 92 days, p=0.672). Both EGFR-TKIs showed similar toxicity. In a multivariate analysis using Cox regression model, adenocarcinoma was an independent predictor of survival (p=0.006; hazard ratio [HR], 0.487; 95% confidence interval [CI], 0.292-0.811). Analyses of subgroups did not show any difference in response predictors between gefitinib and erlotinib. Conclusion: Comparing gefitinib to erlotinib, there were no differences in the response rate, overall survival, progression-free survival, or toxicity. No specific predictor of response to each EGFR-TKI was identified.

• Tuberculosis and Respiratory Diseases
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• v.55 no.5
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• pp.488-498
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• 2003

Background : Activation of the transcription factor NF-${\kappa}B$ has been shown to protect cells from tumor necrosis factor-alpha, chemotherapy, and radiation-induced apoptosis. NF-${\kappa}B$-dependent cIAP expression is a major antiapoptotic mechanism for that. NF-${\kappa}B$ activation and cIAP expression in A549 lung cancer cells which is relatively resistant to radiation-induced cell death were investigated for the mechanism of radioresistance. Materials and methods : We used A549 lung cancer cells and Clinac 1800C linear accelerator for radiation. Cell viability test was done by MTT assay. NF-${\kappa}B$ activation was tested by luciferase reporter gene assay, Western blot for $I{\kappa}B{\alpha}$ degradation, and electromobility shift assay. For blocking ${\kappa}B$, MG132 and transfection of $I{\kappa}B{\alpha}$-superrepressor plasmid construct were used. cIAP expression was analyzed by RT-PCR and cIAP2 promoter activity was performed using luciferase assay system. Results : MTT assay showed that cytotoxicity even 48 hr after radiation in A549 cells were less than 20%. Luciferas assay demonstrated weak NF-${\kappa}B$ activation of $1.6{\pm}0.2$ fold compared to PMA-induced $3.4{\pm}0.9$ fold. Radiation-induced $I{\kappa}B{\alpha}$ degradation was observed in Western blot and NF-${\kappa}B$ DNA binding was confirmed by EMSA. However, blocking NF-${\kappa}B$ using MG132 and $I{\kappa}B{\alpha}$-superrepressor transfection did not show any sensitizing effect for radiation-induced cell death. The result of RT-PCR for cIAP1 & 2 expression was negative induction while TNF-${\alpha}$ showed strong expression for cIAP1 & 2. The cIAP2 promoter activity also did not show any change compared to positive control with TNF-${\alpha}$. Conclusion : We conclude that activation of NF-${\kappa}B$ does not determine the intrinsic radiosensitivity of cancer cells, at least for the cell lines tested in this study.

• Tuberculosis and Respiratory Diseases
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• v.60 no.1
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• pp.57-64
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• 2006

Background : Recently, there have been several studies showing that irinotecan hydrochloride, a topoisomerase I inhibitor, is effective against extensive disease(ED) small cell lung cancer (SCLC). We conducted a phase II trial to evaluate the efficacy and toxicity of irinotecan plus cisplatin as a 1st line therapy for both limited and extensive disease SCLC. Methods : The study was conducted between January 2002 and June 2004. Patients were treated with $60mg/m^2$ irinotecan on day 1, 8, 15 and $60mg/m^2$ cisplatin on day 1, every 4 weeks. During concurrent thoracic irradiation for limited disease (LD)-SCLC patients, dose of irinotecan was reduced to $40mg/m^2$. Prophylactic cranial irradiation was given to patients with complete remission (CR) after chemotherapy. Results : Median ages of LD- and ED- SCLC were 64 years and performance status (PS) was 0-2. In patients with LD-SCLC, the response rate after concurrent chemoradiotherapy was 85% (CR, 6; Partial response [PR], 11). The median survival was 20 months (95% CIs, 15.6 to 24.4) with 1-and 2-year survival rates of 85% and 35%, respectively. Median progression free survival (PFS) was 12 months (95% CIs, 6.2 to 18.1) with 1- year PFS of 36%. In ED-SCLC, the response rate was 83.4% (CR, 1; PR, 14). The median survival was 14.5 months (95% CIs, 8.8 to 20.1) with 1-year survival rates of 75%. Median PFS was 6.3 months (95% CIs, 5.6 to 7.1) with 1- year PFS of 20%. The major toxicities (grade 3 or 4) of this regimen included leukopenia, anemia, thrombocytopenia, nausea/vomiting, and diarrhea without life threatening complication. Conclusion : Our data shows that the combination of irinotecan plus cisplatin as a first line therapy is effective and tolerable in the treatment of both LD- and ED- SCLC.