Insufficient autophagy promotes bronchial epithelial cell senescence in chronic obstructive pulmonary disease

Tobacco smoke-induced accelerated cell senescence has been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). Cell senescence is accompanied by the accumulation of damaged cellular components suggesting that in COPD, inhibition of autophagy may contribute to cell senescence. Here we look at whether autophagy contributes to cigarette smoke extract (CSE) - induced cell senescence of primary human bronchial epithelial cells (HBEC), and further evaluate p62 and ubiquitinated protein levels in lung homogenates from COPD patients. We demonstrate that CSE transiently induces activation of autophagy in HBEC, followed by accelerated cell senescence and concomitant accumulation of p62 and ubiquitinated proteins. Autophagy inhibition further enhanced accumulations of p62 and ubiquitinated proteins, resulting in increased senescence and senescence-associated secretory phenotype (SASP) with interleukin (IL)-8 secretion. Conversely, autophagy activation by Torin1, a mammalian target of rapamycin (mTOR inhibitor), suppressed accumulations of p62 and ubiquitinated proteins and inhibits cell senescence. Despite increased baseline activity, autophagy induction in response to CSE was significantly decreased in HBEC from COPD patients. Increased accumulations of p62 and ubiquitinated proteins were detected in lung homogenates from COPD patients. Insufficient autophagic clearance of damaged proteins, including ubiquitinated proteins, is involved in accelerated cell senescence in COPD, suggesting a novel protective role for autophagy in the tobacco smoke-induced senescence-associated lung disease, COPD.

Pulmonary Injury from Waterproofing Spray During a Hike

A 48-year-old man developed general fatigue, dyspnea, and fever at an altitude of 1562 m from the morning of the first day of a 3-day hike. Despite pharyngeal discomfort and mild general fatigue, he felt that the symptoms were not sufficient to abandon his plan. He usually required 1.5 hours to reach Tokusawa (6.4 km from the starting point at an altitude of 1500 m), but this time he required 2.5 hours and slept briefly upon arrival at Tokusawa due to extreme fatigue and respiratory discomfort. His symptoms became aggravated, so he presented at a mountain clinic with oxygen saturation at 80% and body temperature of 37.6ºC. He was diagnosed with hypoxemia due to pneumonia and/or other disease(s) and was evacuated to a hospital where a chest computed tomography scan revealed ground glass opacity and infiltrative shadows. He was treated for pneumonia, but another doctor discovered during follow-up that the patient had sprayed 300 mL of a waterproofing aerosol on mountain equipment in a nonventilated, enclosed area of his home on the night before starting out on the hike. Therefore, waterproofing spray was considered to have caused pulmonary damage. Self-reporting or appropriate questionnaires are the only means of identifying this type of injury. The differential diagnosis of pulmonary problems in an outdoor setting should include toxic aerosol exposure from waterproofing spray.

Identification of pathogens by comprehensive real-time PCR versus conventional methods in community-acquired pneumonia in Japanese adults

BACKGROUND

Community-acquired pneumonia (CAP) has high morbidity and mortality. Unfortunately, the pathogen detection rate using conventional culture methods is relatively low. We compared comprehensive real-time polymerase chain reaction (real-time PCR) analysis of nasopharyngeal swab specimens (NPS) and sputum samples against conventional methods for ability to detect causative pathogens of CAP.

METHODS

We prospectively enrolled adult CAP patients, including those with prior antibiotic use, from December 2012 to May 2014. For each patient, causative pathogens were investigated conventionally and by real-time PCR that can identify 6 bacterial and 11 viral pathogens.

RESULTS

Patients numbered 92 (mean age, 63 years; 59 male), including 30 (33%) with prior antibiotic use. Considering all patients, identification of causative pathogens by real-time PCR was significantly more frequent than by conventional methods in all patients (72% vs. 57%, p = 0.018). In patients with prior antibiotic use, identification rates also differed significantly (PCR, 77%; conventional, 50%; p = 0.027). Mixed infections were more frequent according to real-time PCR than conventional methods (26% vs. 4%, p < 0.001). By the real-time PCR, Streptococcus pneumoniae was most frequently identified (38%) as a causative pathogen, followed by Haemophilus influenzae (37%) and Mycoplasma pneumoniae (5%). PCR also identified viral pathogens (21%), with sensitivity enhanced by simultaneous examination of both NPS and sputum samples rather than only NPS samples.

CONCLUSIONS

Real-time PCR of NPS and sputum samples could better identify bacterial and viral pathogens in CAP than conventional methods, both overall and in patients with prior antibiotic treatment.

Involvement of PARK2-Mediated Mitophagy in Idiopathic Pulmonary Fibrosis Pathogenesis

Fibroblastic foci, known to be the leading edge of fibrosis development in idiopathic pulmonary fibrosis (IPF), are composed of fibrogenic myofibroblasts. Autophagy has been implicated in the regulation of myofibroblast differentiation. Insufficient mitophagy, the mitochondria-selective autophagy, results in increased reactive oxygen species, which may modulate cell signaling pathways for myofibroblast differentiation. Therefore, we sought to investigate the regulatory role of mitophagy in myofibroblast differentiation as a part of IPF pathogenesis. Lung fibroblasts were used in in vitro experiments. Immunohistochemical evaluation in IPF lung tissues was performed. PARK2 was examined as a target molecule for mitophagy regulation, and a PARK2 knockout mouse was employed in a bleomycin-induced lung fibrosis model. We demonstrated that PARK2 knockdown-mediated mitophagy inhibition was involved in the mechanism for activation of the platelet-derived growth factor receptor (PDGFR)/PI3K/AKT signaling pathway accompanied by enhanced myofibroblast differentiation and proliferation, which were clearly inhibited by treatment with both antioxidants and AG1296, a PDGFR inhibitor. Mitophagy inhibition-mediated activation of PDGFR signaling was responsible for further autophagy suppression, suggesting the existence of a self-amplifying loop of mitophagy inhibition and PDGFR activation. IPF lung demonstrated reduced PARK2 with concomitantly increased PDGFR phosphorylation. Furthermore, bleomycin-induced lung fibrosis was enhanced in PARK2 knockout mice and subsequently inhibited by AG1296. These findings suggest that insufficient mitophagy-mediated PDGFR/PI3K/AKT activation, which is mainly attributed to reduced PARK2 expression, is a potent underlying mechanism for myofibroblast differentiation and proliferation in fibroblastic foci formation during IPF pathogenesis.

PARK2-mediated mitophagy is involved in regulation of HBEC senescence in COPD pathogenesis

Cigarette smoke (CS)-induced mitochondrial damage with increased reactive oxygen species (ROS) production has been implicated in COPD pathogenesis by accelerating senescence. Mitophagy may play a pivotal role for removal of CS-induced damaged mitochondria, and the PINK1 (PTEN-induced putative kinase 1)-PARK2 pathway has been proposed as a crucial mechanism for mitophagic degradation. Therefore, we sought to investigate to determine if PINK1-PARK2-mediated mitophagy is involved in the regulation of CS extract (CSE)-induced cell senescence and in COPD pathogenesis. Mitochondrial damage, ROS production, and cell senescence were evaluated in primary human bronchial epithelial cells (HBEC). Mitophagy was assessed in BEAS-2B cells stably expressing EGFP-LC3B, using confocal microscopy to measure colocalization between TOMM20-stained mitochondria and EGFP-LC3B dots as a representation of autophagosome formation. To elucidate the involvement of PINK1 and PARK2 in mitophagy, knockdown and overexpression experiments were performed. PINK1 and PARK2 protein levels in lungs from patients were evaluated by means of lung homogenate and immunohistochemistry. We demonstrated that CSE-induced mitochondrial damage was accompanied by increased ROS production and HBEC senescence. CSE-induced mitophagy was inhibited by PINK1 and PARK2 knockdown, resulting in enhanced mitochondrial ROS production and cellular senescence in HBEC. Evaluation of protein levels demonstrated decreased PARK2 in COPD lungs compared with non-COPD lungs. These results suggest that PINK1-PARK2 pathway-mediated mitophagy plays a key regulatory role in CSE-induced mitochondrial ROS production and cellular senescence in HBEC. Reduced PARK2 expression levels in COPD lung suggest that insufficient mitophagy is a part of the pathogenic sequence of COPD.

Pathogens in COPD exacerbations identified by comprehensive real-time PCR plus older methods

Respiratory infection is a major cause of exacerbation in chronic obstructive pulmonary disease (COPD). Infectious contributions to exacerbations remain incompletely described. We therefore analyzed respiratory tract samples by comprehensive real-time polymerase chain reaction (PCR) in combination with conventional methods. We evaluated multiple risk factors for prolonged hospitalization to manage COPD exacerbations, including infectious agents. Over 19 months, we prospectively studied 46 patients with 50 COPD exacerbations, collecting nasopharyngeal swab and sputum samples from each. We carried out real-time PCR designed to detect six bacterial species and eleven viruses, together with conventional procedures, including sputum culture. Infectious etiologies of COPD exacerbations were identified in 44 of 50 exacerbations (88%). Infections were viral in 17 of 50 exacerbations (34%). COPD exacerbations caused by Gram-negative bacilli, including enteric and nonfermenting organisms, were significantly associated with prolonged hospitalization for COPD exacerbations. Our results support the use of a combination of real-time PCR and conventional methods for determining both infectious etiologies and risk of extended hospitalization.

Autophagy induction by SIRT6 through attenuation of insulin-like growth factor signaling is involved in the regulation of human bronchial epithelial cell senescence

Cigarette smoke (CS)-induced cellular senescence has been implicated in the pathogenesis of chronic obstructive pulmonary disease, and SIRT6, a histone deacetylase, antagonizes this senescence, presumably through the attenuation of insulin-like growth factor (IGF)-Akt signaling. Autophagy controls cellular senescence by eliminating damaged cellular components and is negatively regulated by IGF-Akt signaling through the mammalian target of rapamycin (mTOR). SIRT1, a representative sirtuin family, has been demonstrated to activate autophagy, but a role for SIRT6 in autophagy activation has not been shown. Therefore, we sought to investigate the regulatory role for SIRT6 in autophagy activation during CS-induced cellular senescence. SIRT6 expression levels were modulated by cDNA and small interfering RNA transfection in human bronchial epithelial cells (HBECs). Senescence-associated β-galactosidase staining and Western blotting of p21 were performed to evaluate senescence. We demonstrated that SIRT6 expression levels were decreased in lung homogenates from chronic obstructive pulmonary disease patients, and SIRT6 expression levels correlated significantly with the percentage of forced expiratory volume in 1 s/forced vital capacity. CS extract (CSE) suppressed SIRT6 expression in HBECs. CSE-induced HBEC senescence was inhibited by SIRT6 overexpression, whereas SIRT6 knockdown and mutant SIRT6 (H133Y) without histone deacetylase activity enhanced HBEC senescence. SIRT6 overexpression induced autophagy via attenuation of IGF-Akt-mTOR signaling. Conversely, SIRT6 knockdown and overexpression of a mutant SIRT6 (H133Y) inhibited autophagy. Autophagy inhibition by knockdown of ATG5 and LC3B attenuated the antisenescent effect of SIRT6 overexpression. These results suggest that SIRT6 is involved in CSE-induced HBEC senescence via autophagy regulation, which can be attributed to attenuation of IGF-Akt-mTOR signaling.

Lung adenocarcinoma complicated by Trousseau's syndrome successfully treated by a combination of anticoagulant therapy and chemotherapy

A 63-year-old woman was diagnosed with advanced lung adenocarcinoma complicated by Trousseau's syndrome characterized by non-bacterial thrombotic endocarditis, asymptomatic brain infarction, deep venous thrombosis, and low-grade disseminated intravascular coagulation (DIC). The patient's DIC rapidly became widespread, and multiple micropulmonary embolisms led to severe respiratory failure. She received a blood transfusion and anticoagulant treatment with heparin and recombinant human soluble thrombomodulin, which modestly ameliorated her symptoms, and additional chemotherapy led to tumor shrinkage with concomitant resolution of Trousseau's syndrome. Although there are no established medical approaches for managing Trousseau's syndrome, intensive anticoagulant treatment may be effective for improving the patients' general condition in order for them to be able to undergo subsequent combination chemotherapy.

Mitochondrial fragmentation in cigarette smoke-induced bronchial epithelial cell senescence

Mitochondria are dynamic organelles that continuously change their shape through fission and fusion. Disruption of mitochondrial dynamics is involved in disease pathology through excessive reactive oxygen species (ROS) production. Accelerated cellular senescence resulting from cigarette smoke exposure with excessive ROS production has been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). Hence, we investigated the involvement of mitochondrial dynamics and ROS production in terms of cigarette smoke extract (CSE)-induced cellular senescence in human bronchial epithelial cells (HBEC). Mitochondrial morphology was examined by electron microscopy and fluorescence microscopy. Senescence-associated β-galactosidase staining and p21 Western blotting of primary HBEC were performed to evaluate cellular senescence. Mitochondrial-specific superoxide production was measured by MitoSOX staining. Mitochondrial fragmentation was induced by knockdown of mitochondrial fusion proteins (OPA1 or Mitofusins) by small-interfering RNA transfection. N-acetylcysteine and Mito-TEMPO were used as antioxidants. Mitochondria in bronchial epithelial cells were prone to be more fragmented in COPD lung tissues. CSE induced mitochondrial fragmentation and mitochondrial ROS production, which were responsible for acceleration of cellular senescence in HBEC. Mitochondrial fragmentation induced by knockdown of fusion proteins also increased mitochondrial ROS production and percentages of senescent cells. HBEC senescence and mitochondria fragmentation in response to CSE treatment were inhibited in the presence of antioxidants. CSE-induced mitochondrial fragmentation is involved in cellular senescence through the mechanism of mitochondrial ROS production. Hence, disruption of mitochondrial dynamics may be a part of the pathogenic sequence of COPD development.

A survival case of invasive thymoma accompanied by acute fulminant myocarditis

Thymomas are associated with a wide spectrum of autoimmune paraneoplastic diseases. Here we report the case of 31-year-old male with invasive thymoma, myasthenia gravis, polymyositis, and acute fulminant myocarditis that presented with cardiogenic shock requiring intra-aortic balloon pumping and percutaneous cardiopulmonary support. Corticosteroid therapy was effective. To our knowledge, this is the first case of thymoma with acute fulminant cardiomyositis that was successfully treated by assisted circulation and corticosteroids, despite a poor prognosis.

Insufficient autophagy in idiopathic pulmonary fibrosis

Autophagy, a process that helps maintain homeostatic balance between the synthesis, degradation, and recycling of organelles and proteins to meet metabolic demands, plays an important regulatory role in cellular senescence and differentiation. Here we examine the regulatory role of autophagy in idiopathic pulmonary fibrosis (IPF) pathogenesis. We test the hypothesis that epithelial cell senescence and myofibroblast differentiation are consequences of insufficient autophagy. Using biochemical evaluation of in vitro models, we find that autophagy inhibition is sufficient to induce acceleration of epithelial cell senescence and myofibroblast differentiation in lung fibroblasts. Immunohistochemical evaluation of human IPF biospecimens reveals that epithelial cells show increased cellular senescence, and both overlaying epithelial cells and fibroblasts in fibroblastic foci (FF) express both ubiquitinated proteins and p62. These findings suggest that insufficient autophagy is an underlying mechanism of both accelerated cellular senescence and myofibroblast differentiation in a cell-type-specific manner and is a promising clue for understanding the pathogenesis of IPF.

Organizing pneumonia complicated by cyst and pneumothorax formation

We present a case of organizing pneumonia complicated by pneumothorax in association with cyst formation that developed during corticosteroid treatment. Although it has been reported that the check-valve mechanism is a plausible cause of cyst and pneumothorax formation in patients with organizing pneumonia, the details of the corresponding pathological changes that occur in air-trapping have not been elucidated. A pathological examination of lung specimens obtained with video-assisted thoracoscopic surgery suggested that granulation tissues plugging the bronchiole lumens might be a potential cause of the check-valve mechanism in this case. In this report, we also reviewed eight other cases of organizing pneumonia with pneumothorax or cyst formation.

Involvement of creatine kinase B in cigarette smoke-induced bronchial epithelial cell senescence

Cigarette smoke induces damage to proteins and organelles by oxidative stress, resulting in accelerated epithelial cell senescence in the lung, which is implicated in chronic obstructive pulmonary disease (COPD) pathogenesis. Although the detailed molecular mechanisms are not fully understood, cellular energy status is one of the most crucial determinants for cell senescence. Creatine kinase (CK) is a constitutive enzyme, playing regulatory roles in energy homeostasis of cells. Among two isozymes, brain-type CK (CKB) is the predominant CK in lung tissue. In this study, we investigated the role of CKB in cigarette smoke extract (CSE)-induced cellular senescence in human bronchial epithelial cells (HBECs). Primary HBECs and Beas2B cells were used. Protein carbonylation was evaluated as a marker of oxidative protein damage. Cellular senescence was evaluated by senescence-associated β-galactosidase staining. CKB inhibition was examined by small interfering RNA and cyclocreatine. Secretion of IL-8, a hallmark of senescence-associated secretary phenotype, was measured by ELISA. CKB expression levels were reduced in HBECs from patients with COPD compared with that of HBECs from nonsmokers. CSE induced carbonylation of CKB and subsequently decreased CKB protein levels, which was reversed by a proteasome inhibitor. CKB inhibition alone induced cell senescence, and further enhanced CSE-induced cell senescence and IL-8 secretion. CSE-induced oxidation of CKB is a trigger for proteasomal degradation. Concomitant loss of enzymatic activity regulating energy homeostasis may lead to the acceleration of bronchial epithelial cell senescence, which is implicated in the pathogenesis of COPD.

Insulin-dependent phosphatidylinositol 3-kinase/Akt and ERK signaling pathways inhibit TLR3-mediated human bronchial epithelial cell apoptosis

TLR3, one of the TLRs involved in the recognition of infectious pathogens for innate and adaptive immunity, primarily recognizes viral-associated dsRNA. Recognition of dsRNA byproducts released from apoptotic and necrotic cells is a recently proposed mechanism for the amplification of toxicity, suggesting a pivotal participation of TLR3 in viral infection, as well as in lung diseases where apoptosis plays a critical role, such as asthma and chronic obstructive pulmonary disease. In addition to metabolic control, insulin signaling was postulated to be protective by inhibiting apoptosis. Therefore, we explored the role of insulin signaling in protecting against TLR3-mediated apoptosis of human bronchial epithelial cells. Significant TLR3-mediated apoptosis was induced by polyinosinic-polycytidylic acid, a dsRNA analog, via caspase-8-dependent mechanisms. However, insulin efficiently inhibited TLR3/polyinosinic-polycytidylic acid-induced human bronchial epithelial cell apoptosis via PI3K/Akt and ERK pathways, at least in part, via upregulation of cellular FLIPs and through protein synthesis-independent mechanisms. These results indicate the significance of TLR3-mediated dsRNA-induced apoptosis in the pathogenesis of apoptosis-driven lung disease and provide evidence for a novel protective role of insulin.

Neurally mediated syncope associated with small cell lung cancer: a case report and review

We encountered a case of limited-disease small cell lung cancer with episodic syncope. The frequency of the syncopal attacks increased with the increase in the tumor size, thus a relationship was suspected to exist between the SCLC and syncope. Syncope was evaluated by history taking, 24-hour ECG monitoring, and coronary angiography. As orthostatic hypotension and cardiac disease could be excluded, we finally diagnosed this case as neurally mediated syncope. Serum tests for anti-Hu and anti-Yo antibodies were negative. A temporary pacemaker was inserted for sick sinus syndrome. This patient showed good response to the chemotherapy. No further syncopal attacks were observed after the second course of chemotherapy. Here, in addition we review four cases of SCLC with episodic syncope. Interestingly, in all cases, the tumor was located in the left hilum in close vicinity of the afferent vagal nerve (C-fibers) and mechano-receptor. Therefore, we thought that the mechanism underlying the syncope was mechano-receptor hypersensitivity.

Accelerated epithelial cell senescence in IPF and the inhibitory role of SIRT6 in TGF-β-induced senescence of human bronchial epithelial cells

Reepithelialization of remodeled air spaces with bronchial epithelial cells is a prominent pathological finding in idiopathic pulmonary fibrosis (IPF) and is implicated in IPF pathogenesis. Recent studies suggest that epithelial senescence is a risk factor for development of IPF, indicating such reepithelialization may be influenced by the acceleration of cellular senescence. Among the sirtuin (SIRT) family, SIRT6, a class III histone deacetylase, has been demonstrated to antagonize senescence. We evaluated the senescence of bronchiolization in association with SIRT6 expression in IPF lung. Senescence-associated β-galactosidase staining and immunohistochemical detection of p21 were performed to evaluate cellular senescence. As a model for transforming growth factor (TGF)-β-induced senescence of abnormal reepithelialization, we used primary human bronchial epithelial cells (HBEC). The changes of SIRT6, p21, and interleukin (IL)-1β expression levels in HBEC, as well as type I collagen expression levels in fibroblasts, were evaluated. In IPF lung samples, an increase in markers of senescence and SIRT6 expression was found in the bronchial epithelial cells lining cystically remodeled air spaces. We found that TGF-β induced senescence in primary HBEC by increasing p21 expression, and, whereas TGF-β also induced SIRT6, it was not sufficient to inhibit cellular senescence. However, overexpression of SIRT6 efficiently inhibited TGF-β-induced senescence via proteasomal degradation of p21. TGF-β-induced senescent HBEC secreted increased amounts of IL-1β, which was sufficient to induce myofibroblast differentiation in fibroblasts. These findings suggest that accelerated epithelial senescence plays a role in IPF pathogenesis through perpetuating abnormal epithelial-mesenchymal interactions, which can be antagonized by SIRT6.

[A case of small cell lung cancer with dermatomyositis that deteriorated with leukocytopenia due to chemotherapy]

A 64-year-old woman presented skin lesions on her face, upper extremities and finger erythema (heliotropism and Gottron's sign). She had weakness in her lower extremities. She was given a diagnosis of dermatomyositis (DM), because the serum examination showed that a myositis-specific antibody was positive whereas Jo-1 antibody was negative. The findings of chest X-ray and computed tomography showed that she had limited small cell lung cancer, but no interstitial pneumonia. She was treated with standard chemotherapy consisting of cisplatin and etoposide with accelerated hyperfractionation radiotherapy. She showed partial response to the treatment, whereas the skin lesions and muscle weakness deteriorated accompanied with bone marrow suppression due to chemotherapy. Skin and muscle biopsy were performed and pathological findings showed typical perivasculitis infiltrated with lymphocytes in muscle and skin. With the recovery of bone marrow suppression and partial response due to chemotherapy, the skin lesions improved and creatine kinase became normalized. She was given a diagnosis of paraneoplastic DM. Since severe leukocytopenia paralleled the deterioration of DM, the decrease of peripheral white blood cell counts, especially regulatory T cell counts, may be associated with DM activity.

Response of a thymic mucoepidermoid carcinoma to combination chemotherapy with cisplatin and irinotecan: A case report

A chemotherapeutic regimen for advanced thymic carcinoma has not yet been established. We describe a patient with advanced thymic mucoepidermoid carcinoma who achieved a complete response to combination chemotherapy with cisplatin (Randa) and irinotecan hydrochloride (Campto). A 74-year-old man was admitted to our hospital because of chest pain, general fatigue, appetite loss and weight loss. Chest computed tomography examinations revealed an anterior mediastinal tumour (5.5cmx3.5cmx9.5cm) that had invaded the subcutis through the sternum. The patient was treated with three courses of cisplatin and irinotecan hydrochloride followed by radiotherapy; he has since exhibited a complete response for 3 months.

Detection of epidermal growth factor receptor mutations in serum as a predictor of the response to gefitinib in patients with non-small-cell lung cancer

Cases of non-small-cell lung cancer (NSCLC) carrying the somatic mutation of epidermal growth factor receptor (EGFR) have been shown to be hyperresponsive to the EGFR tyrosine kinase inhibitor gefitinib (IRESSA). If EGFR mutations can be observed in serum DNA, this could serve as a noninvasive source of information on the genotype of the original tumor cells that could influence treatment and the ability to predict patient response to gefitinib. Serum genomic DNA was obtained from Japanese patients with NSCLC before first-line gefitinib monotherapy. Scorpion Amplified Refractory Mutation System technology was used to detect EGFR mutations. Wild-type EGFR was detected in all of the 27 serum samples. EGFR mutations were detected in 13 of 27 (48.1%) patients and two major EGFR mutations were identified (E746_A750del and L858R). The EGFR mutations were seen significantly more frequently in patients with a partial response than in patients with stable disease or progressive disease (P = 0.046, Fisher's exact test). The median progression-free survival was significantly longer in patients with EGFR mutations than in patients without EGFR mutations (200 versus 46 days; P = 0.005, log-rank test). The median survival was 611 days in patients with EGFR mutations and 232 days in patients without EGFR mutations (P > 0.05). In pairs of tumor and serum samples obtained from 11 patients, the EGFR mutation status in the tumors was consistent with those in the serum of 8 of 11 (72.7%) of the paired samples. Thus, EGFR mutations were detectable using Scorpion Amplified Refractory Mutation System technology in serum DNA from patients with NSCLC. These results suggest that patients with EGFR mutations seem to have better outcomes with gefitinib treatment, in terms of progression-free survival, overall survival, and response, than those patients without EGFR mutations.

[Problems associated with molecular targeted drugs for cancer]

Molecular targeted drugs have been developed and have come to play a part in the standard treatment of cancers. However, issues such as the optimum dose, selection of patients, and verification of the molecular targets remain to be discussed, because unexpected clinical problems related to the clinical efficacy, adverse events, and development of resistance have appeared. Therefore, proof of principle (POP) studies and pharmacodynamic or pharmacogenomic research to explore new bio-markers for the drugs are essential for clinical progress. On the other hand, the higher cost of development and care must also be discussed as new problems.

A randomized phase II study of sequential carboplatin/paclitaxel (CP) and gefitinib (G) in chemotherapy-naïve patients with advanced non-small-cell lung cancer (NSCLC): Preliminary results

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Background: G has been shown to exhibit antitumor activity against NSCLC, however, the optimal timing of its administration remains unclear. We conducted a randomized phase II study of CP followed by G or G followed by CP in chemotherapy-naïve advanced NSCLC patients in order to select the candidate arm for a subsequent phase III study. Methods: Chemotherapy-naïve patients with histologically or cytologically confirmed NSCLC, stage IIIB or IV, aged between 20 to74 years, performance status 0–1, were randomized to either Arm A (carboplatin (AUC 6, day 1) plus paclitaxel (200 mg/m2, day 1) every 3 weeks for 4 courses followed by daily G (250 mg/day)) or Arm B (daily G until disease progression followed by CP every 3 weeks for 4 courses). The primary endpoint was overall survival, and the planned sample size for this randomized phase II study was 96 patients (Liu’s selection design for pilot studies on survival). Results: From June 2003 to October 2005, 97 patients were enrolled, and 96 of these patients were treated in this study. Forty-nine patients (males/females: 28/21, median age: 63 years, adeno/non-adeno: 43/6, stageIII/IV: 11/38, smoker/non-smoker: 27/22) were randomized to Arm A and 48 patients (males/females: 28/20, median age: 61 years, adeno/non-adeno: 42/6, stageIII/IV: 11/37, smoker/non-smoker: 28/20) to Arm B. The response rate to CP in Arm A was 32.7% (16/49), and that to G in Arm B was 29.8% (14/47). The median survival was not yet reached, and the 1-year survival rates were 64.5% and 70.5% in Arm A and arm B, respectively. As of January 2006, one patient had died of treatment-related perforative peritonitis and two patients had developed interstitial lung disease. Conclusions: G exhibits similar antitumor activity to CP in chemotherapy-naïve patients with advanced NSCLC. The preliminary survival analysis is proposed to be conducted in April 2006.

No significant financial relationships to disclose.

[Comparison of five guidelines of community-acquired pneumonia]

The aim of this retrospective study was to elucidate the characteristics of five guidelines of community-acquired pneumonia: ATS (1993), ATS (2001), IDSA (1998), IDSA (2000) and the guidelines of the Japan Respiratory Society (2000). One hundred community-acquired pneumonia patients admitted to the International Medical Center of Japan were investigated in accordance with each set of guidelines based on the physical, laboratory, and chest radiography findings on the first day of treatment. According to the ATS (1993) guidelines, 33% of the cases were classified as "severe" pneumonia. On the other hand, according to the ATS (2001) guidelines, only 8% of the cases were classified as "severe" pneumonia. According to the IDSA guidelines, 35% of the patients were classified as "outpatients". Fluoroquinolone appears to be a very important antibiotic drug in the new guidelines of both ATS and IDSA. The scoring system of IDSA suggested a correlation between the patient's score and the pathogenic bacteria. According to the guidelines of the Japan Respiratory Society, 42% of the cases were classified as "severe" pneumonia. There are evident differences between these guidelines, and clinicians need to have a full understanding of their respective characteristics.