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Purpose: NF-E2-related factor 2 (Nrf2), a key transcription regulator for antioxidant and detoxification enzymes, is abundantly expressed in cancer cells. In this study, therefore, the role of Nrf2 in cancer cell proliferation and resistance to anticancer drugs was investigated.Experimental Design: We used three human lung cancer cell lines with different degrees of Nrf2 activation: Nrf2 was highly activated in A549 cells, slightly activated in NCI-H292 cells, and not activated in LC-AI cells under unstimulated conditions.Result: A549 cells showed higher resistance to cisplatin compared with NCI-H292 and LC-AI cells. The resistance to cisplatin was significantly inhibited in A549 but not in NCI-H292 or LC-AI cells by knockdown of Nrf2 with its specific small interfering RNA (Nrf2-siRNA). The cell proliferation was also most prominently inhibited in A549 cells by treatment with Nrf2-siRNA. In A549 cells, the expression of self-defense genes, such as antioxidant enzymes, phase II detoxifying enzymes, and drug efflux pumps, was significantly reduced by Nrf2-siRNA concomitant with a reduction of the cellular glutathione level. The degree of DNA crosslink and apoptosis after treatment with cisplatin was significantly elevated in A549 cells by Nrf2-siRNA. Knockdown of Nrf2 arrested the cell cycle at G1 phase with a reduction of the phosphorylated form of retinoblastoma protein in A549 and NCI-H292 cells but not in LC-AI cells.Conclusion: These results indicate that the Nrf2 system is essential for both cancer cell proliferation and resistance to anticancer drugs. Thus, Nrf2 might be a potential target to enhance the effect of anticancer drugs.

PDF file, 23K, Primers used in RT-PCR.

Invariant NKT (iNKT) cells play an important role in a variety of antimicrobial immune responses due to their ability to produce high levels of immune-modulating cytokines. Here, we investigated the role of iNKT cells in host defense against candidiasis using Jα18-deficient mice (Jα18(-/-) ), which lack iNKT cells. Jα18(-/-) mice were more resistant to the development of lethal candidiasis than wild-type (WT) mice. In contrast, treatment of WT mice with the iNKT cell activating ligand α-galactosylceramide markedly enhanced their mortality after infection with Candida albicans. Serum IL-10 levels were significantly elevated in WT mice in response to infection with C. albicans. Futhermore, IL-10 production increased after in vitro coculture of peritoneal macrophages with iNKT cells and C. albicans. The numbers of peritoneal macrophages, the production of IL-1β and IL-18, and caspase-1 activity were also significantly elevated in Jα18(-/-) mice after infection with C. albicans. The adoptive transfer of iNKT cells or exogenous administration of IL-10 into Jα18(-/-) reversed susceptibility to candidiasis to the level of WT mice. These results suggest that activation of iNKT cells increases the initial severity of C. albicans infection, most likely mediated by IL-10 induced modulation of macrophage antifungal activity.

Summary Background We demonstrated previously that GATA-3 overexpression markedly enhanced allergen-induced airway inflammation and airway remodelling, including subepithelial fibrosis, and smooth muscle cell hyperplasia, in transgenic mice. Objective Because cysteinyl leukotrienes (cysLTs) have been shown to be involved in such structural changes, the effects of a specific cysLT1 receptor antagonist, montelukast, were evaluated in a mouse model of chronic asthma. Methods GATA-3-overexpressing mice and wild-type Balb/c mice were sensitized and repeatedly challenged by ovalbumin (OVA) or saline. The effects of montelukast on the development of airway remodelling were compared between the two mouse genotypes. Results CysLTs in the lung were increased after repeated allergen challenges, and significantly enhanced in GATA-3-overexpressing mice. The enhanced cysLT levels were accompanied by the development of eosinophilia, smooth muscle cell hyperplasia, and increased stromal cell-derived factor-1 gene expression with a small increase in pro-collagen gene expression in OVA-challenged GATA-3-overexpressing mice, but not in wild-type mice. Montelukast significantly decreased lung cysLT levels and inhibited the GATA-3-overexpression-related airway remodelling, potently preventing smooth muscle cell hyperplasia, but partially suppressed the increased pro-collagen gene expression and eosinophilic inflammation. Increases in the levels of IL-4, IL-5, IL-13, and eotaxin in bronchial lavage and TGF-β gene expression in the lungs were induced by OVA in both mouse genotypes. Montelukast treatment also significantly reduced these levels to the levels seen after saline challenges in GATA-3-overexpressing mice. Conclusion Montelukast efficaciously prevented airway inflammation and remodelling in a GATA-3-overexpression antigen challenge mouse model by decreasing the cysLT-driven Th2 cytokine cycle of amplification of airway pathologies. Cite this as: T. Kiwamoto, Y. Ishii, Y. Morishima, K. Yoh, N. Kikuchi, N. Haraguchi, H. Masuko, M. Kawaguchi, A. Nomura, T. Sakamoto, S. Takahashi and N. Hizawa, Clinical & Experimental Allergy, 2011 (41) 116–128.

Candidaspecies are the most common source of nosocomial invasive fungal infections. Previous studies have indicated that T-helper immune response is the critical host factor for susceptibility toCandidainfection. The transcription factor GATA-3 is known as the master regulator for T-helper type 2 (Th2) differentiation. We therefore investigated the role of GATA-3 in the host defense against systemicCandidainfection using GATA-3-overexpressing transgenic mice. The survival of GATA-3-overexpressing mice afterCandidainfection was significantly lower than that of wild-type mice.Candidaoutgrowth was significantly increased in the kidneys of GATA-3-overexpressing mice, compared with wild-type mice. The levels of various Th2 cytokines, including interleukin-4 (IL-4), IL-5, and IL-13, were significantly higher while the level of Th1 cytokine gamma interferon was significantly lower in the splenocytes of GATA-3-overexpressing mice afterCandidainfection. Recruitment of macrophages into the peritoneal cavity in response toCandidainfection and their phagocytic activity were significantly lower in GATA-3-overexpressing mice than in wild-type mice. Exogenous administration of gamma interferon to GATA-3-overexpressing mice significantly reducedCandidaoutgrowth in the kidney and thus increased the survival rate. Administration of gamma interferon also increased the recruitment of macrophages into the peritoneal cavity in response toCandidainfection. These results indicate that overexpression of GATA-3 modulates macrophage antifungal activity and thus enhances the susceptibility to systemicCandidainfection, possibly by reducing the production of gamma interferon in response toCandidainfection.

Hypersensitivity pneumonitis (HP) is mediated by a Th1 immune response. Transcription factor GATA binding protein-3 (GATA-3) is believed to be a key regulator of Th2 differentiation and thus might play regulatory roles in the pathogenesis of hypersensitivity pneumonitis (HP).We examined the effect of GATA-3 overexpression on the development of HP in mice.Wild-type C57BL/6 mice and GATA-3-overexpressing mice of the same background were used in this study. HP was induced by repeated exposure to Saccharopolyspora rectivirgula, the causative antigen of farmer's lung.Antigen exposure resulted in a marked inflammatory response with enhanced pulmonary expression of T-bet and the Th1 cytokine interferon (IFN)-gamma in wild-type mice. The degree of pulmonary inflammation was much less severe in GATA-3-overexpressing mice. The induction of T-bet and IFN-gamma genes was suppressed, but a significant induction of Th2 cytokines, including IL-5 and IL-13, was observed in the lungs of GATA-3-overexpressing mice after antigen exposure. Supplementation with recombinant IFN-gamma enhanced lung inflammatory responses in GATA-3-overexpressing mice to the level of wild-type mice. Because antigen-induced IFN-gamma production predominantly occurred in CD4+ T cells, nude mice were transferred with CD4+ T cells from either wild-type or GATA-3-overexpressing mice and subsequently exposed to antigen. Lung inflammatory responses were significantly lower in nude mice transferred with CD4+ T cells from GATA-3-overexpressing mice than in those with wild-type CD4+ T cells, with a reduction of lung IFN-gamma level.These results indicate that overexpression of GATA-3 attenuates the development of HP by correcting the Th1-polarizing condition.

Oxidative stress plays an important role in the pathogenesis of acute lung injury and pulmonary fibrosis. Peroxiredoxin (Prx) I is a cellular antioxidant enzyme induced under stress conditions. In the present study, the protective effects of Prx I on the development of bleomycin-induced acute pulmonary inflammation and pulmonary fibrosis were investigated using Prx I-deficient mice. Survival of Prx I-deficient mice after bleomycin administration was significantly lower than that of wild-type mice, corresponding with enhanced acute pulmonary inflammation and fibrosis. The level of inflammatory cytokines and chemokines, such as TNF-α, macrophage inflammatory protein-2, and monocyte chemotactic protein-1, was significantly elevated in the bronchoalveolar lavage fluid of Prx I-deficient mice after bleomycin administration. Furthermore, the level of 8-isoprostane, an oxidative stress marker, and the concentration and alveolar macrophage expression of macrophage migration inhibitory factor were elevated in the lungs of Prx I-deficient mice after bleomycin administration. The exacerbation of bleomycin-induced pulmonary inflammation and fibrosis in Prx I-deficient mice was inhibited by treatment with N-acetyl-L-cysteine, a radical scavenger, or with (S,R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid methyl ester, a tautomerase inhibitor of macrophage migration inhibitory factor. These findings suggest that mice lacking Prx I are highly susceptible to bleomycin-induced pulmonary inflammation and fibrosis because of increases in pulmonary oxidant levels and macrophage migration inhibitory factor activity in response to bleomycin.

Purpose: NF-E2-related factor 2 (Nrf2), a key transcription regulator for antioxidant and detoxification enzymes, is abundantly expressed in cancer cells. In this study, therefore, the role of Nrf2 in cancer cell proliferation and resistance to anticancer drugs was investigated. Experimental Design: We used three human lung cancer cell lines with different degrees of Nrf2 activation: Nrf2 was highly activated in A549 cells, slightly activated in NCI-H292 cells, and not activated in LC-AI cells under unstimulated conditions. Result: A549 cells showed higher resistance to cisplatin compared with NCI-H292 and LC-AI cells. The resistance to cisplatin was significantly inhibited in A549 but not in NCI-H292 or LC-AI cells by knockdown of Nrf2 with its specific small interfering RNA (Nrf2-siRNA). The cell proliferation was also most prominently inhibited in A549 cells by treatment with Nrf2-siRNA. In A549 cells, the expression of self-defense genes, such as antioxidant enzymes, phase II detoxifying enzymes, and drug efflux pumps, was significantly reduced by Nrf2-siRNA concomitant with a reduction of the cellular glutathione level. The degree of DNA crosslink and apoptosis after treatment with cisplatin was significantly elevated in A549 cells by Nrf2-siRNA. Knockdown of Nrf2 arrested the cell cycle at G1 phase with a reduction of the phosphorylated form of retinoblastoma protein in A549 and NCI-H292 cells but not in LC-AI cells. Conclusion: These results indicate that the Nrf2 system is essential for both cancer cell proliferation and resistance to anticancer drugs. Thus, Nrf2 might be a potential target to enhance the effect of anticancer drugs.

Background The proportion of tumor disappearance rate (TDR) on conventional computed tomography (CT) is associated with less aggressive biology, and patients with small peripheral adenocarcinoma accompanied by the TDR component showed better prognosis. These findings led us to the idea that even advanced-stage adenocarcinomas with a higher TDR in the primary lesion on CT might suggest slowly progressing cancer. This study was designed to determine the value of the TDR area in the primary site of advanced-stage lung adenocarcinoma with CT and correlate the CT findings with clinical outcome. Patients and Methods In 103 patients with stage IIIB and IV lung adenocarcinoma, CT appearances and clinical data were reviewed retrospectively. Three methods were used in the evaluation of the TDR area: method I, consolidation on mediastinal windows/mass on lung windows > 75% or not; method II, maximum diameter on mediastinal windows/maximum diameter on lung windows (diameter ratio) > 75% or not; and method III, TDR area on lung windows > 25% or not. Results In univariate analysis, patients with lung adenocarcinoma with TDR have a more favorable prognosis than those without TDR in all 3 methods (method I, P = 0.001; method II, P = 0.024; method III, P = 0.014; log-rank test). In multivariate analysis, a favorable prognosis in patients with adenocarcinoma with TDR was shown in method I ( P = 0.015) and method III ( P = 0.006). Conclusion As shown in patients with small peripheral lung adenocarcinoma, those with TDR on CT tended to have a good prognosis in contrast to those without TDR, even in patients with advanced-stage lung adenocarcinoma. Prospective study to confirm these results will be required.

Since the time that antibiotics have come into common use, pseudoaneurysms in the pulmonary artery resulting from infectious conditions have been extremely rare. We herein present the case of a patient with familial diabetes mellitus, who had lung suppuration with a pseudoaneurysmal cyst in his pulmonary artery. Only use of enhanced (as opposed to plain) computed tomography (CT) could provide us with the clue that led us to presume this rare condition as a provisional diagnosis prior to surgery.

We described a 70 years old patient with pericardial effusion due to adenocarcinoma of the lung, in whom gefitinib, which is an oral selective inhibitor of the epidermal growth factor receptor of tyrosine kinase, demonstrated a marked antitumor effect. We recommend possible consideration of a treatment with gefitinib for female patients with pericarditis carcinomatosa due to lung adenocarcinoma, even if they have a poor performance status and are not indicated for other intensive therapy.

Plasmacytoma is an uncommon tumor and is rarely encountered as a primary pulmonary neoplasm. Herein we describe the conventional radiographic and computed tomographic findings in a patient with a primary pulmonary plasmacytoma.

Background Pulmonary fibrosis is a progressive and lethal disorder. Although the precise mechanisms of pulmonary fibrosis are not fully understood, oxidant/antioxidant and Th1/Th2 balances may play an important role in many of the processes of inflammation and fibrosis. The transcription factor Nrf2 acts as a critical regulator for various inflammatory and immune responses by controlling oxidative stress. We therefore investigated the protective role of Nrf2 against the development of pulmonary fibrosis. Methods To generate pulmonary fibrosis, both wild-type C57BL/6 mice and Nrf2-deficient mice of the same background were administered bleomycin intratracheally. Results The survival of Nrf2-deficient mice after bleomycin administration was significantly lower than that of wild-type mice. The degree of bleomycin-induced initial pulmonary inflammation and pulmonary fibrosis was much more severe in Nrf2-deficient mice than in wild-type mice. The expression of antioxidant enzymes and phase II detoxifying enzymes was significantly reduced in the lungs of Nrf2-deficient mice, concomitant with an elevation of lung 8-isoprostane level, compared with wild-type mice. The expression of Th2 cytokines, such as interleukin-4 and interleukin-13, was significantly elevated in the lungs of Nrf2-deficient mice with an increase in the number of Th2 cells that express GATA-binding protein 3. Conclusions The results indicated that Nrf2 protects against the development of pulmonary fibrosis by regulating the cellular redox level and lung Th1/Th2 balance. Thus, Nrf2 might be an important genetic factor in the determination of susceptibility to pulmonary fibrosis.