Kwan Hyoung Kim

Effect of Nilotinib on Bleomycin-Induced Acute Lung Injury and Pulmonary Fibrosis in Mice

Background: The tyrosine kinase inhibitor imatinib mesylate was developed as an inhibitor of the kinase activity of BCR-ABL. However, imatinib also has potent inhibitory activity against the platelet-derived growth factor receptor (PDGFR). Nilotinib is approved for treating patients with chronic myeloid leukemia showing resistance or intolerance to imatinib. Like imatinib, nilotinib selectively inhibits the tyrosine kinase activity of PDGFR. Objectives: We examined the effect of imatinib and nilotinib on acute lung injury and pulmonary fibrosis in a mouse model. Methods: Mice were treated by intratracheal instillation of bleomycin. Imatinib or nilotinib were administered by oral gavage. To study the early inflammatory and late fibrotic phases of lung injury, mice were sacrificed on days 3, 7, 14 and 21 after bleomycin instillation. Results: Histopathology showed that imatinib and nilotinib attenuated the extent of lung injury and fibrosis. The numbers of inflammatory cells and levels of IL-6, IL-1β and tumor necrosis factor-α were decreased in the imatinib and nilotinib groups on days 3 and 7. Imatinib and nilotinib therapy significantly reduced the levels of hydroxyproline on days 14 and 21, which was accompanied by decreased expression levels of transforming growth factor (TGF)-β1 and PDGFR-β. Imatinib and nilotinib also significantly reduced the expression levels of the genes for TGF-β1 and platelet-derived growth factor (PDGF). Imatinib and nilotinib treatment also significantly inhibited the PDGF-induced proliferation of lung fibroblasts in vitro. When imatinib or nilotinib was given 7 days after the instillation of bleomycin, only nilotinib attenuated pulmonary fibrosis. Conclusions: Imatinib and nilotinib attenuated bleomycin-induced acute lung injury and pulmonary fibrosis in mice. In a therapeutic model, nilotinib showed more potent antifibrotic effects than imatinib.

Expression of vascular endothelial growth factor and hypoxiainducible factor in the airway of asthmatic patients

BACKGROUND Vascular endothelial growth factor (VEGF) is a potent proangiogenic cytokine, and it also increases vascular permeability. It is well known that VEGF levels are increased in the airway of asthmatic patients. Hypoxia-inducible factor (HIF) induces a rapid and strong increase in VEGF expression. OBJECTIVES To evaluate the relationship between VEGF level and clinical characteristics and to determine whether VEGF expression is associated with HIF expression in asthmatic patients. METHODS Bronchoscopy was performed on 30 asthmatic patients and 14 control subjects. The concentration of VEGF in the bronchoalveolar lavage fluid (BALF) was examined using enzyme-linked immunosorbent assay. We measured VEGF, HIF-1alpha, and HIF-2alpha expression on biopsy specimens by means of immunoreactivity. RESULTS The VEGF level in the BALF was significantly higher in asthmatic patients than in controls. The VEGF level correlated with eosinophil counts in the BALF in asthmatic subjects (r = 0.501; P < .01). However, the VEGF level did not correlate with percentage of forced expiratory volume in 1 second and airway hyperresponsiveness. Asthmatic patients exhibited higher VEGF, HIF-1alpha, and HIF-2alpha immunoreactivity in the submucosa than did controls. Furthermore, VEGF expression correlated significantly with HIF-1alpha (r = 0.614; P = .02) and HIF-2alpha (r = 0.881; P = .001) expression. CONCLUSION These findings suggest that VEGF may play an important role in inflammation and that VEGF level is related to HIF in bronchial asthma.

Detection and comparison of EGFR mutations in matched tumor tissues, cell blocks, pleural effusions, and sera from patients with NSCLC with malignant pleural effusion, by PNA clamping and direct sequencing

Peptide nucleic acid (PNA)-mediated real-time PCR clamping has higher sensitivity than conventional direct sequencing for detecting mutations. Pleural effusion and serum may provide good samples in which to detect epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) patients. We studied 37 NSCLC patients with malignant pleural effusion. EGFR mutations were assessed by PNA clamping and direct sequencing using tumor tissues, cell blocks, pleural effusion, and serum. Concordance between PNA clamping and direct sequencing results, and the diagnostic performance of pleural effusion were investigated. The κ coefficients for the two methods were 0.68 (p = 0.0007), 0.91 (p < 0.0001), 0.75 (p < 0.0001) and -0.01 (p = 0.8639) for tissues, cell blocks, pleural effusion, and serum, respectively. The diagnostic performance of pleural effusion compared with the combination of tumor tissue and cell blocks showed 89% sensitivity, 100% specificity, positive predictive value of 100%, and negative predictive value of 95% by PNA clamping, and 67% sensitivity, 90% specificity, positive predictive value of 75%, and negative predictive value of 86% by directing sequencing. A patient in whom an EGFR mutation was identified in pleural effusion only by PNA clamping showed a significant response to EGFR tyrosine kinase inhibitor (EGFR-TKI) treatment. In contrast to the limited role of serum samples, pleural effusion had a diagnostic performance for the detection of EGFR mutations in NSCLC that was comparable to that of tumor tissues and cell blocks. The diagnostic performance of PNA clamping was good compared with that of direct sequencing. A more sensitive and accurate detection of EGFR mutations would benefit patients by allowing a better prediction of the response to EGFR-TKI treatment.

Prognostic factors in critically ill patients with hematologic malignancies admitted to the intensive care unit.

OBJECTIVE Despite an improvement in the prognosis of patients with hematologic malignancies, the mortality of such patients transferred to the intensive care unit (ICU) is high. This study determined the predictors of mortality in a cohort of critically ill patients with hematologic malignancies admitted to the ICU. METHODS We studied 227 critically ill patients with hematologic malignancies who were admitted to the ICU between April 2009 and December 2011. A cohort of consecutive patients with hematologic malignancies was reviewed retrospectively to identify clinically useful prognostic factors. RESULTS The ICU mortality rate was 84.1%, and the in-hospital mortality rate was 89.9%. The ICU mortality was significantly higher in patients with acute leukemia than in those with other malignancies. A significant difference between survivors and nonsurvivors was found in neutropenia and its recovery during the ICU stay, presence of cardiac dysfunction, the need for an invasive mechanical ventilator, use of inotropic/vasopressor agents, platelet count, aspartate transaminase level, pH, and Acute Physiology And Chronic Health Evaluation II score. In the multivariate analysis, acute leukemia, need for invasive mechanical ventilator, use of inotropic/vasopressor agents, and Acute Physiology And Chronic Health Evaluation II scores were independently associated with a worse outcome in patients with hematologic malignancies admitted to the ICU. CONCLUSION Higher mortality in patients with hematologic malignancies admitted to the ICU is associated with more severe illness, as reflected by higher organ failure scores or respiratory or hemodynamic instability. Mortality is higher in patients with acute leukemia as compared with other hematologic malignancies.

Vitamin D Receptor Gene TaqI, BsmI and FokI Polymorphisms in Korean Patients with Tuberculosis

Background The active metabolite (1, 25-dihydroxycholecalciferol) of vitamin D (25-hydroxycholecalciferol) leads to activation of macrophages and deficiency of vitamin D seems to be involved in the risk of tuberculosis. The effects of vitamin D are exerted by interaction with the vitamin D receptor (VDR) and may be influenced by polymorphism in the VDR gene. In this study, variation in the VDR gene was investigated in Korean population with tuberculosis. Methods We typed three VDR polymorphisms of restriction endonuclease sites for TaqI, BsmI and FokI in 155 patients with tuberculosis and 105 healthy volunteers. Results The frequencies of FokI genotypes determined from TB patients were 29.13% for FF, 56.31% for Ff, and 14.56% for ff. We observed 1.4-fold increased prevalence of the Ff genotype in TB patients compared with normal healthy groups (p=0.0857). However, there was no significant association between the genotype groups, TB patient and normal control, for FokI polymorphism. There was also no significant association between VDR gene and tuberculosis in another polymorphism (BsmI and TaqI). Conclusion Three polymorphisms (TaqI, BsmI and FokI) in the VDR gene do not appear to be responsible for host susceptibility to human tuberculosis in Korean population.

Inflammatory and Remodeling Events in Asthma with Chronic Exposure to House Dust Mites: A Murine Model

Although animal models with ovalbumin have been used to study chronic asthma, there are difficulties in inducing recurrence as well as in maintaining chronic inflammation in this system. Using a murine model of house dust mite (HDM)-induced bronchial asthma, we examined the airway remodeling process in response to the chronic exposure to HDM. During the seventh and twelfth weeks of study, HDM were inhaled through the nose for three consecutive days and airway responsiveness was measured. Twenty-four hours later, bronchoalveolar lavage and histological examination were performed. The degree of overproduction of mucus, subepithelial fibrosis, and the thickness of the peribronchial smooth muscle in the experimental group was clearly increased compared to the control group. In addition, HDM-exposed mice demonstrated severe airway hyperreactivity to methacholine. In the bronchoalveolar lavage fluid, the number of total cells and eosinophils was increased; during the twelfth week, the number of neutrophils increased in the experimental group. With regard to changes in cytokines, the concentrations of IL-4, IL-13, and transforming growth factor-beta (TGF-β) were increased in the experimental group. The data suggest that eosinophils, IL-4, IL-13, and TGF-β might play an important role in the airway remodeling process and that neutrophils may be involved with increased exposure time.

Time Sequence of Airway Remodeling in a Mouse Model of Chronic Asthma: the Relation with Airway Hyperresponsiveness

During the course of establishing an animal model of chronic asthma, we tried to elucidate the time sequence of airway hyperresponsiveness (AHR), airway inflammation, airway remodeling, and associated cytokines. Seven-week-old female BALB/c mice were studied as a chronic asthma model using ovalbumin (OVA). After sensitization, mice were exposed twice weekly to aerosolized OVA, and were divided into three groups depending on the duration of 4 weeks, 8 weeks, and 12 weeks. At each time point, airway responsiveness, inflammatory cells, cytokines in bronchoalveolar lavage fluids (BALF), serum OVA-specific IgE, IgG1, IgG2a, and histological examination were carried out. AHR to methacholine, increased levels of OVA-specific IgG1 and IgG2a, and goblet cell hyperplasia were continuously sustained at each time point of weeks. In contrast, we observed a time-dependent decrease in serum OVA-specific IgE, BALF eosinophils, BALF cytokines such as IL-13, transforming growth factor-beta1, and a time-dependent increase in BALF promatrix metalloproteinase-9 and peribronchial fibrosis. In this OVA-induced chronic asthma model, we observed airway remodelings as well as various cytokines and inflammatory cells being involved in different time-dependent manners. However, increased airway fibrosis did not directly correlate with a further increase in airway hyperresponsiveness.

Co-administration of vaccination with DNA encoding T cell epitope on the Der p and BCG inhibited airway remodeling in a murine model of chronic asthma.

Therapeutic modalities of airway remodeling in asthma have proved to be unsuccessful regarding reversing the previously established chronic airway changes. Recently, the potential of plasmid DNA to inhibit the Th2 immune response has been demonstrated in animal models of asthma. Bacillus Calmette-Guerin (BCG) immunization also induced immunomodulation, which appeared to be reliant on the properties of the interferon-gamma that was produced. Mice were immunized with house dust mite extract (HDM). At the 3 week point, we injected BCG subcutaneously into mice on three successive weeks. One week after the BCG injection, we immunized mice with the DNA plasmid encoding for murine T-cell epitope on Dermatophagoide pteronyssinus 2 thrice weekly. At 9 weeks after immunization, we measured airway responsiveness. Twenty four hours later, we performed bronchoalveolar lavage and histological examinations. Co-administration of DNA vaccination and BCG resulted in a partial suppression of the overproduction of goblet cells and the thickness of the peribronchial smooth muscle in ongoing allergic responses. In the bronchoalveolar lavage fluid, the number of total cells and eosinophils was reduced, and regarding the change of cytokines, the concentration of IL-4 was also decreased, but interferon-gamma was increased in the co-administration group, opposed to the asthma group. These results suggest that co-administration of vaccination with the DNA encoding T-cell epitope and BCG are effective regarding ongoing allergic response and might constitute an ideal method for combating allergic disease in the future.

Protective effect of pravastatin on lipopolysaccharide-induced acute lung injury during neutropenia recovery in mice

ABSTRACT Although neutropenia recovery is associated with deterioration of preexisting acute lung injury (ALI), there are few reports of the preventive strategies. Statins have been found to attenuate inflammatory responses in murine models of lipopolysaccharide (LPS)-induced ALI. The aim of this study was to determine whether pravastatin could attenuate ALI during neutropenia recovery in mice. Cyclophosphamide was administered to mice to induce neutropenia. Mice were given intratracheal LPS 7 days after cyclophosphamide administration, after which pravastatin was administered by intraperitoneal injection. In order to study the effects of pravastatin, mice were killed on day 5. Pravastatin attenuated the pulmonary edema and histopathological changes of LPS-induced lung injury. The accumulation of neutrophils and the concentrations of TNF-α, IL-1β, IL-6, and MPO in BAL fluids were also effectively inhibited by pravastatin. The expression levels of Toll-like receptor 4, nuclear factor kappa B, tumor growth factor-β and matrix metalloproteinase-9 were significantly reduced by pravastatin. Taken together, pravastatin significantly attenuated LPS-induced ALI during neutropenia recovery. These results provide evidence for the potential of pravastatin in the treatment of ALI during neutropenia recovery.

A multicenter phase II study of belotecan, a new camptothecin analogue, as a second-line therapy in patients with small cell lung cancer.

Belotecan (Camtobell, CKD602) is a new camptothecin derivative antitumor agent that belongs to the topoisomerase inhibitors. The aim of this phase II study was to evaluate the efficacy and safety of single agent belotecan as a second-line therapy in patients with small cell lung cancer (SCLC). Patients who were previously treated for SCLC were entered into the study. Belotecan was given by daily intravenous infusion for five consecutive days, every three weeks. Twenty-five patients were enrolled in this study. On an intention-to-treat basis, belotecan induced an overall response rate of 24%, a median overall survival of 9.9 months, a median time to progression of 2.2 months, and a 1-year survival rate of 38.3%. Grade 3/4 neutropenia developed in 88.0% of patients and grade 3/4 thrombocytopenia in 40.0%. Nonhematologic toxicity of grade 3 or 4 was low. The results suggest that belotecan is relatively active and well tolerated as a second-line agent in patients with SCLC.