Potentiation of Muscarinic M3 Receptor Activation through a New Allosteric Site with a Novel Positive Allosteric Modulator ASP8302.

Muscarinic M3 (M3) receptors mediate a wide range of acetylcholine (ACh)-induced functions, including visceral smooth-muscle contraction and glandular secretion. Positive allosteric modulators (PAMs) can avoid various side effects of muscarinic agonists with their spatiotemporal receptor activation control and potentially better subtype selectivity. However, the mechanism of allosteric modulation of M3 receptors is not fully understood, presumably because of the lack of a potent and selective PAM. In this study, we investigated the pharmacological profile of ASP8302, a novel PAM of M3 receptors, and explored the principal site of amino-acid sequences in the human M3 receptor required for the potentiation of receptor activation. In cells expressing human M3 and M5 receptors, ASP8302 shifted the concentration-response curve (CRC) for carbachol to the lower concentrations with no significant effects on other subtypes. In a binding study with M3 receptor-expressing membrane, ASP8302 also shifted the CRC for ACh without affecting the binding of orthosteric agonists. Similar shifts in the CRC of contractions by multiple stimulants were also confirmed in isolated human bladder strips. Mutagenesis analysis indicated no interaction between ASP8302 and previously reported allosteric sites; however, it identified threonine 230 as the amino acid essential for the PAM effect of ASP8302. These results demonstrate that ASP8302 enhances the activation of human M3 receptors by interacting with a single amino acid distinct from the reported allosteric sites. Our findings suggest not only a novel allosteric site of M3 receptors but also the potential application of ASP8302 to diseases caused by insufficient M3 receptor activation. SIGNIFICANCE STATEMENT: The significance of this study is that the novel M3 receptor positive allosteric modulator ASP8302 enhances the activation of human M3 receptor by interacting with a residue distinct from the reported allosteric sites. The finding of Thr230 as a novel amino acid involved in the allosteric modulation of M3 receptors provides significant insight into further research of the mechanism of allosteric modulation of M3 and other muscarinic receptors.

Phase II study of amrubicin plus erlotinib in previously treated, advanced non-small cell lung cancer with wild-type epidermal growth factor receptor (TORG1320).

Background Amrubicin (AMR) is a completely synthetic 9-aminoanthracycline and clinically active against non-small cell lung cancer (NSCLC). We conducted a phase I study of AMR and erlotinib (ERL) combination therapy in previously treated patients with advanced NSCLC and have already reported the safety and effectiveness. Methods We conducted a multi-center, single-arm phase II trial to evaluate the efficacy of AMR and ERL combination therapy in patients with previously treated, advanced NSCLC harboring wild-type EGFR, PS 0-1 and < 75 years of age. Patients were treated at 3-week intervals with AMR plus ERL. The primary endpoint was the PFS, and the secondary endpoints were the response rate (RR), disease control rate (DCR), overall survival (OS) and toxicity. The trough ERL concentration (Ctrough) was measured as an exploratory study to analyze the relationship between the efficacy/safety and pharmacokinetics. Results From June 2013 to July 2016, 25 patients were enrolled in this trial. The PFS according to the central test was 3.6 months (95% confidence interval 2.1-5.1). The RR and DCR were 24.0% and 64.0%, respectively. We had no treatment-related deaths in this study. Conclusions The PFS of AMR and ERL combination therapy was superior to that of AMR monotherapy in the historical setting, but the primary endpoint was not met in this trial. In our study, the pharmacokinetic analysis showed that the Ctrough of ERL was elevated with combination therapy. This combination therapy might be a viable treatment for previously treated NSCLC patients without a driver oncogene mutation. Clinical trial information UMIN 000010582.

Safety and effectiveness of alectinib in a real-world surveillance study in patients with ALK-positive non-small-cell lung cancer in Japan.

We conducted a large-scale surveillance study as a post-marketing commitment to investigate the safety and effectiveness of alectinib in patients with ALK-positive non-small-cell lung cancer (NSCLC) in Japan. Patients receiving 300 mg twice-daily alectinib (September 2014 to June 2015) were monitored until termination of alectinib or completion of 18 months of treatment at 519 Japanese study sites. The primary endpoint was the incidence of adverse drug reactions (ADR), which are important identified risks for alectinib in Japanese patients. Overall survival (OS), a key secondary endpoint, was assessed according to information on outcome. Overall, 1251 patients were enrolled. The median patient age was 62.0 years; 12.9% of patients were aged ≥75 years. At baseline, 63.0% of patients had received crizotinib and 40.6% had brain metastases. Altogether, 1512 ADR occurred in 654 patients (53.6%), with 164 grade ≥3 ADR in 123 patients (10.1%). Commonly occurring ADR were hepatic disorders (all grades, 19.8%; grade ≥3, 2.0%), decreased neutrophil and/or white blood cell count (all grades, 7.6%; grade ≥3, 1.1%), and interstitial lung disease (all grades, 3.8%; grade ≥3, .7%). Median OS was not estimable. The 18-month cumulative OS rate was longer in patients with ECOG performance status ≤1 (vs 2 or ≥3; 83.7% vs 44.5% or 27.2%), without prior crizotinib (vs with; 81.1% vs 73.4%), receiving first-line alectinib (vs second and third or later line; 83.0% vs 79.2% or 71.9%), without brain metastases (vs with; 79.5% vs 71.5%). These data confirm the favorable safety and effectiveness of alectinib in patients with ALK-positive NSCLC in Japan.

Effect of ASP2205 fumarate, a novel 5-HT2C receptor agonist, on urethral closure function in rats.

The pharmacological profile of ASP2205 fumarate (ASP2205), a novel 5-HT2C receptor agonist, was evaluated in vitro and in vivo. ASP2205 showed potent and selective agonistic activity for the human 5-HT2C receptor, with an EC50 of 0.85 nM in the intracellular Ca2+ mobilization assay. Rat 5-HT2C receptor was also activated by ASP2205 with an EC50 of 2.5 nM. Intraduodenal administration (i.d.) of ASP2205 (0.1-1 mg/kg) significantly elevated the leak point pressure (LPP) in anesthetized rats in a dose-dependent manner. This ASP2205 (0.3 mg/kg i.d.)-induced LPP elevation was inhibited by SB242084 (0.3 mg/kg i.v.), a selective 5-HT2C receptor antagonist. Urethral closure responses induced by intravesical pressure loading in rats were enhanced by ASP2205 (0.3 mg/kg i.v.), which was abolished by pretreatment with SB242084 (0.3 mg/kg i.v.) and bilateral transection of the pudendal nerve. In contrast, ASP2205 (0.3 mg/kg i.v.) did not change the resting urethral pressure in rats. These results indicate that ASP2205 can enhance the pudendal nerve-mediated urethral closure reflex via the 5-HT2C receptor, resulting in the prevention of involuntary urine loss.

Effect of ASP6432, a Novel Type 1 Lysophosphatidic Acid Receptor Antagonist, on Urethral Function and Prostate Cell Proliferation.

Current pharmacotherapies for lower urinary tract symptoms associated with benign prostate hyperplasia (LUTS/BPH) are in need of improvement. Lysophosphatidic acid (LPA) is a phospholipid with various biologic functions. However, its exact role in the lower urinary tract and its target receptor subtype have not been fully elucidated. We investigated the role of LPA and the type 1 LPA receptor (LPA1) in urethral/prostatic contractile function and prostate cell proliferation by pharmacologically characterizing ASP6432 (potassium 1-(2-{[3,5-dimethoxy-4-methyl-N-(3-phenylpropyl)benzamido]methyl}-1,3-thiazole-4-carbonyl)-3-ethyl-2,2-dioxo-2λ6-diazathian-1-ide), a novel LPA1 antagonist. ASP6432 exhibited potent and selective antagonistic activity against LPA1 in cells expressing LPA receptor subtypes. In isolated rat tissue strips and anesthetized rats, ASP6432 concentration-/dose-dependently inhibited LPA-induced urethra and prostate contractions. In addition, in anesthetized rats, ASP6432 maximally decreased the urethral perfusion pressure (UPP) in the absence of exogenous LPA stimulation by 43% from baseline, whereas tamsulosin, an α1-adrenoceptor antagonist, reduced UPP by 22%. Further, in human prostate stromal cells, ASP6432 significantly and concentration-dependently suppressed LPA-induced bromodeoxyuridine incorporation. These results demonstrate a pivotal role for LPA and LPA1 in the regulation of urethral tonus and prostate cell proliferation. The potent urethral relaxation and inhibition of prostatic stromal cell growth indicate the potential of ASP6432 as a novel therapeutic agent for LUTS/BPH.

Phase I study of Nedaplatin, a platinum based antineoplastic drug, combined with nab-paclitaxel in patients with advanced squamous non-small cell lung cancer.

Background This study was designed to determine the recommended dose of a combination of nedaplatin (NED) and nab-paclitaxel (nab-PTX) in chemotherapy-naive patients with advanced squamous non-small-cell lung cancer (NSCLC). Methods Patients received escalating doses of NED on day 1 and nab-PTX on days 1, 8, and 15 every 4 weeks by an intravenous infusion for up to six cycles. Results A dose of 100 mg/m2 NED and 100 mg/m2 nab-PTX was determined to be the recommended dose for patients with advanced squamous NSCLC. The study had an overall response rate of 66.7% (95% confidence interval [CI]: 38.4-88.2) and disease control rate of 93.3% (95% CI: 68.1-99.8). The median progression-free survival time and survival time was 7.0 months (95% CI: 5.9-8.1) and 13.1 months (95% CI: 6.2-20.1), respectively. The most common adverse events were neutropenia (grade 3/4, 33%) and leukopenia (grade 3/4, 27%). Although peripheral neuropathy was observed in 5 patients (grade 1/2), non-hematological toxic effects were relatively mild. Febrile neutropenia, pneumonitis, and treatment-related death were not observed. Conclusions The combination of NED and nab-PTX was a tolerable and effective regimen and its recommended dose was 100 mg/m2 and 100 mg/m2, respectively, in chemotherapy-naive patients with advanced squamous NSCLC (UMIN000010963).

Phase II study of bevacizumab, cisplatin, and docetaxel plus maintenance bevacizumab as first-line treatment for patients with advanced non-squamous non-small-cell lung cancer combined with exploratory analysis of circulating endothelial cells: Thoracic Oncology Research Group (TORG)1016.

BACKGROUND: Preclinical studies have demonstrated that docetaxel and bevacizumab may act synergistically by decreasing endothelial cell proliferation and preventing circulating endothelial progenitor mobilization. The objective of this study was to assess the efficacy and safety of a combination therapy of bevacizumab, cisplatin, and docetaxel in chemotherapy-naive Japanese patients with advanced non-squamous non-small-cell lung cancer (NSCLC). METHODS: Eligible patients were chemotherapy-naive and had advanced/recurrent non-squamous NSCLC. The patients received 4 cycles of docetaxel (60 mg/m2), cisplatin (80 mg/m2), and bevacizumab (15 mg/kg) once every 3 weeks, followed by bevacizumab as maintenance therapy, every 3 weeks until disease progression or attainment of unacceptable toxicity level. The primary endpoint was objective response rate (ORR). The numbers of circulating endothelial cells (CEC) were also estimated on days 1 and 8 of the first cycle for the exploratory analysis of efficacy prediction. RESULTS: A total of 47 patients were enrolled from October 2010 to April 2012. Bevacizumab as maintenance therapy was administered to 41 patients (87.2%), and the median number of total treatment cycles was 9 (range: 1-36). ORR, median progression-free survival (PFS), and median overall survival of the patients were 74.5%, 9.0 months, and 27.5 months, respectively. The most common grade 3/4 adverse event was neutropenia (95.7%), followed by leukopenia (59.6%) and hypertension (46.8%). PFS was longer in patients with ≥10 count increase in CECs than that in patients with < 10 count increase in CECs (respective median PFS of 11.0 months versus 6.90 months) although the difference was not statistically significant (p = 0.074). CONCLUSIONS: A combination therapy of bevacizumab, cisplatin, and docetaxel, followed by bevacizumab as maintenance was highly effective in patients with non-squamous NSCLC despite the high incidence of grade 3/4 neutropenia. The increase in CEC count between days 1 and 8 may predict the efficacy of our bevacizumab-contained treatment regimen. TRIAL REGISTRATION: UMIN Clinical Trial Registry; UMIN000004368 . Registered date; October 11, 2010 (Retrospectively registered).

The role of prophylactic cranial irradiation for patients with small-cell lung cancer.

Small-cell lung cancer (SCLC) has a particular propensity to metastasize to the brain, affecting ~10% of SCLC patients at diagnosis, but may occur in more than 50% of 2-year survivors. Most cytotoxic drugs have limited ability to cross the blood-brain barrier, and the effectiveness of chemotherapy for brain metastasis is limited. Therefore, prophylactic cranial irradiation (PCI) has been proposed to treat SCLC. A meta-analysis revealed that PCI significantly decreased the risk of brain metastasis and increased the 3-year survival rate; it has been established as a standard therapy for limited-disease SCLC. However, certain aspects of PCI remain unclarified, including the roles in resected SCLC and extensive-disease SCLC, and its neurotoxicities. In addition, information on PCI has been obtained from old clinical trials without the use of new imaging devices, such as magnetic resonance imaging. Evidence from advanced imaging techniques is needed in this era.

Basigin expression as a prognostic indicator in stage I pulmonary adenocarcinoma.

We established the KU-Lu-8 monoclonal antibody (MoAb) using a lung cancer cell line as an antigen and a random immunization method. The KU-Lu-8 MoAb recognizes basigin (BSG), which is a transmembrane-type glycoprotein that is strongly expressed on the cell membranes of lung cancer cells. This study aimed to clarify the relationships between BSG expression and clinicopathological parameters and determine the prognostic significance of BSG expression in pulmonary adenocarcinoma (AC) patients. To evaluate the significance of BSG expression in lung cancer, we immunohistochemically analyzed 113 surgically resected pulmonary adenocarcinomas, and the associations between BSG expression and various clinicopathological parameters were evaluated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to investigate the effects of BSG expression on survival. Clinicopathologically, BSG expression was significantly associated with tumor differentiation, vascular invasion, lymphatic invasion, and a poor prognosis. In particular, BSG expression was significantly correlated with poorer survival in patients with stage I AC. The high BSG expression group (compared with the low BSG expression group) exhibited adjusted hazard ratios for mortality of 4.694. BSG expression is indicative of a poor prognosis in AC patients, particularly in those with stage I disease.

Phase II study of Amrubicin monotherapy in elderly or poor-risk patients with extensive disease of small cell lung cancer.

Background Previous study indicated that an optional anti-cancer drug for the treatment of small-cell lung cancer (SCLC) is amrubicin. However, no prospective studies have evaluated amrubicin in chemo-naive elderly or poor-risk patients with SCLC. Therefore, this study aimed to evaluate the efficacy of amrubicin as first-line chemotherapy for elderly or poor-risk patients with extensive-disease SCLC (ES-SCLC). Methods Patients with chemotherapy-naive ES-SCLC received multiple cycles of 40 mg/m2 amrubicin for 3 consecutive days every 21 days. The primary endpoint was the overall response rate (ORR), and the secondary endpoints were progression-free survival (PFS), overall survival (OS), and safety. Results Between March 2011 and August 2015, 36 patients were enrolled in this study. Each patient received a median of four treatment cycles (range, 1-6 cycles). ORR was 52.8% [95% confidence interval (CI), 37-69%]. The median PFS and OS periods were 5.0 months (95% CI, 3.4-6.6 months) and 9.4 months (95% CI, 5.2-13.6 months), respectively. Neutropenia was the most common grade 3 or 4 adverse event (69.4%), with febrile neutropenia developing in 13.9% of patients. No treatment-related death occurred. At the time of starting second-line chemotherapy, 19 of 22 patients (86%) had significantly improved or maintained their performance status (PS) relative to their PS at the time of starting amrubicin monotherapy as first-line chemotherapy (P = 0.027). Conclusions The results of the present study suggest that amrubicin could be considered as a viable treatment option for chemotherapy-naive elderly or poor-risk patients with ES-SCLC (Clinical trial registration number: UMIN000011055 www.clinicaltrials.gov ).

Impact of PD-L1 Expression in Patients with Surgically Resected Non-Small-Cell Lung Cancer.

BACKGROUND: Immunotherapy can become a crucial therapeutic option to improve the prognosis of patients with non-small-cell lung cancer (NSCLC). Here, we evaluated the impact of programmed cell death ligand-1 (PD-L1) expression in surgically resected NSCLCs. METHODS: We estimated PD-L1 expression in 229 consecutive NSCLC specimens using rabbit polyclonal antibodies to human PD-L1 in a SP263 immunohistochemical assay and evaluated PD-L1 expression for potential associations with clinicopathological parameters and survival time. RESULTS: PD-L1 expression was significantly higher in tumors from men or current smokers. Squamous cell carcinoma histology was independently associated with high PD-L1 expression according to multivariate analysis (p = 0.015). The 5-year survival rate of patients was 70%, and the difference in the 5-year survival rate according to PD-L1 expression was not statistically significant (high expression group [67%] vs. low expression group [68%]); however, the squamous cell carcinoma group exhibited significantly lower 5-year survival rates as compared to the non-squamous cell carcinoma group (53 and 71%, respectively; p = 0.026). CONCLUSION: Here, we revealed high PD-L1 expression and poor prognosis observed in patients with surgically resected squamous NSCLC as compared with non-squamous NSCLC. Our results support the identification of patient subsets that most likely respond to anti-PD-1 therapy as the first step in precision medicine.

Phase I/II study of induction chemotherapy using carboplatin plus irinotecan and sequential thoracic radiotherapy (TRT) for elderly patients with limited-disease small-cell lung cancer (LD-SCLC): TORG 0604.

BACKGROUND: The role of irinotecan for elderly patients with LD-SCLC has been unclear, and the timing of TRT combined with chemotherapy has not been fully evaluated. METHODS: Patients aged > 70 years with untreated, measurable, LD-SCLC, performance status (PS) 0-2, and adequate organ function were eligible. Treatment consisted of induction with carboplatin on day 1 and irinotecan on days 1 and 8, every 21 days for 4 cycles, and sequential TRT (54Gy in 27 fractions). Carboplatin doses were based on AUC of 4 and 5 (levels 1 and 2, respectively), with a fixed irinotecan dose (50 mg/m2). Primary objective of the phase II study was overall responce rate. RESULTS: Forty-three patients were enrolled and forty-one were finally analyzed (median age: 75 years [range 70-86 years); males 31; PS 0/1/2, n = 22/18/1]. Two patients were excluded because of protocol violation (ascertained to be extensive disease). Twelve patients were accrued at phase I and the number of patients with carboplatin dose-limiting toxicities at levels-1 (n = 6) and -2 (n = 6) were 1(grade 3 hypertension) and 2 (grade 4 thrombocytopenia), respectively. The phase II trial was expanded to 29 additional patients receiving the level 1 carboplatin dose, total of 35 patients. The median number of chemotherapy cycles was 4 (range 1-4), and the median radiation dose was 54Gy (range 36-60). Toxicities were generally mild. There were 4 complete and 27 partial responses (response rate 88.6%). With a median follow-up of 52 months, the median progression-free and overall survival times of phase II were 11.2 and 27.1 months, respectively. CONCLUSIONS: Induction chemotherapy of carboplatin plus irinotecan and sequential TRT was well tolerated and effective for elderly patients with LD-SCLC. Additional confirmatory studies are warranted. TRIAL REGISTRATION: Trial registration number: UMIN000007352 Name of registry: UMIN. Date of registration: 1/Dec/2006. Date of enrolment of the first participant to the trial: 6/Feb/2007. Clinical trial registration date: 1/Feb/2006 (prospective).

Smoking History as a Predictor of Pemetrexed Monotherapy in Patients with Non-Squamous Non-Small Cell Lung Cancer.

BACKGROUND: Pemetrexed monotherapy has come to be recognized as the standard of care for second-line therapy of non-squamous non-small cell lung cancer (NSCLC). Thymidylate synthase (TS) expression is recognized as a potential predictor of the response to pemetrexed-based chemotherapy in patients with advanced NSCLC. The purpose of this study was to identify useful predictors of the response to pemetrexed other than TS expression. METHODS: The records of non-squamous NSCLC patients without driver mutations who received pemetrexed monotherapy as a second or later line of chemotherapy at Kitasato University Hospital between March 2009 and October 2015 were retrospectively reviewed, and the treatment outcomes were evaluated. RESULTS: In the 116 patients with non-squamous NSCLC, the overall response rate and progression-free survival (PFS) were 10.3% and 2.1 months, respectively. The disease control rate and PFS differed significantly among current smokers and never-smokers/former light smokers (44.9 vs. 65.8%, and 1.8 vs. 4.0 months, respectively). Furthermore, multivariate analysis identified Eastern Cooperative Oncology Group Performance Status and smoking status as independent predictors of the PFS. CONCLUSION: The clinical data obtained in this study may provide a valuable basis for the use of smoking status as a predictor of pemetrexed monotherapy in wild-type NSCLC patients.

Prognostic factors affecting the risk of thoracic progression in extensive-stage small cell lung cancer.

BACKGROUND: The efficacy of combined modality therapy is evaluated for patients with extensive-stage (ES) small cell lung cancer (SCLC). This study evaluated prognostic factors affecting the risk of thoracic progression in ES-SCLC patients likely to undergo thoracic radiotherapy combined chemotherapy. METHODS: A retrospective review of ES-SCLC patients who had received systemic chemotherapy at our hospital was performed. Tumor size, metastatic sites, and laboratory data at diagnosis were evaluated as potential prognostic factors. In ES-SCLC patients without pleural dissemination, the rate of thoracic progression after initial chemotherapy was assessed. RESULTS: Eighty-three of 96 consecutive ES-SCLC patients were analyzed. The overall response rate was 55 %, median progression free survival was 5.0 months (mo), and overall survival (OS) was 9.2 mo. Tumor size (19.4 mo for ≤3 cm vs. 8.5 mo for >3 cm, p = 0.017) and the number of metastatic sites (12.9 mo for single sites vs. 7.1 mo for multiple sites, p = 0.015) were prognostic factors, in addition to known prognostic factors such as performance status and the levels of LDH and sodium. Cox proportional hazard model showed that the OS was significantly worse in patients with large (>3 cm) primary tumor size {HR 2.44 [95 % confidential interval (CI) 1.05-5.68], p = 0.038} and multiple metastatic sites [HR 1.81 (95 % CI 1.08-3.04), p = 0.026]. In 51 cases without pleural dissemination, the number of metastatic sites was associated with thoracic progression after initial chemotherapy (65 % for single sites vs. 36 % for multiple sites, p = 0.036). CONCLUSION: Large tumor size and multiple metastatic sites at diagnosis significantly predicted poor survival in ES-SCLC patients. Based on the high rate of thoracic progression in ES-SCLC patients with single site of distant metastasis, we should consider thoracic radiotherapy combined with chemotherapy for this population.

Actions of cAMP on calcium sensitization in human detrusor smooth muscle contraction.

OBJECTIVES: To clarify the effect of cAMP on the Ca(2+) -sensitized smooth muscle contraction in human detrusor, as well as the role of novel exchange protein directly activated by cAMP (Epac) in cAMP-mediated relaxation. MATERIALS AND METHODS: All experimental protocols to record isometric tension force were performed using α-toxin-permeabilized human detrusor smooth muscle strips. The mechanisms of cAMP-mediated suppression of Ca(2+) sensitization activated by 10 µm carbachol (CCh) and 100 µm GTP were studied using a selective rho kinase (ROK) inhibitor, Y-27632, and a selective protein kinase C (PKC) inhibitor, GF-109203X. The relaxation mechanisms were further probed using a selective protein kinase A (PKA) activator, 6-Bnz-cAMP and a selective Epac activator, 8-pCPT-2'-O-Me-cAMP. RESULTS: We observed that CCh-induced Ca(2+) sensitization was inhibited by cAMP in a concentration-dependent manner. GF-109203X (10 µm) but not Y-27632 (10 µm) significantly enhanced the relaxation effect induced by cAMP (100 µm). 6-Bnz-cAMP (100 µm) predominantly decreased the tension force in comparison with 8-pCPT-2'-O-Me-cAMP (100 µm). CONCLUSIONS: We showed that cAMP predominantly inhibited the ROK pathway but not the PKC pathway. The PKA-dependent pathway is dominant, while Epac plays a minor role in human detrusor smooth muscle Ca(2+) sensitization.

Impact of Smoking History on the Efficacy of Gefitinib in Patients with Non-Small Cell Lung Cancer Harboring Activating Epidermal Growth Factor Receptor Mutations.

BACKGROUND: Gefitinib treatment has come to be recognized as the standard therapy for patients with non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations. However, resistance to gefitinib has been observed in certain subpopulations of these patients. The purpose of this study was to evaluate the impact of smoking status on the efficacy of gefitinib in patients with NSCLC harboring EGFR mutations. METHODS: The records of NSCLC patients harboring EGFR mutations who were treated with gefitinib at Kitasato University Hospital were retrospectively reviewed, and the treatment outcomes were evaluated. RESULTS: In 153 patients with NSCLC harboring EGFR mutations, the overall response rate and progression-free survival (PFS) were 66.7% and 9.0 months, respectively. PFS differed significantly among the current smokers and never-smokers/former light smokers (10.7 vs. 5.4 months, p=0.0002), and the response rate was significantly higher in the never-smokers/former light smokers than in the current smokers (72.3 vs. 55.8%, p=0.04). Multivariate analysis identified smoking status as an independent predictor of PFS. CONCLUSION: The clinical data obtained in this study provide a valuable rationale for considering smoking status as a predictor of the efficacy of gefitinib in patients with NSCLC harboring activating EGFR mutations.

Aminophylline increases respiratory muscle activity during hypercapnia in humans.

BACKGROUND: Theophylline is an old drug traditionally used as a bronchodilator, although it was recently shown to possess anti-inflammatory properties, enhance the actions of corticosteroid actions, and stimulate the respiratory neuronal network. Theophylline has been recognized as an important drug for not only asthma but also corticosteroid-insensitive chronic obstructive pulmonary disease (COPD). To clarify the role of theophylline in hypercapnic ventilatory responses in humans, we analyzed the effects of aminophylline administered at the usual clinical therapeutic doses on ventilation and augmentation of respiratory muscle contractility in room air and under 3 conditions of hypercapnia. STUDY DESIGN: We performed electromyography (EMG) of the parasternal intercostal muscle (PARA) and transversus abdominis muscle (TA) in 7 healthy subjects and recorded both ventilatory parameters and EMG data in room air and under 3 conditions of hypercapnia before (control) and during aminophylline administration. RESULTS: Before aminophylline administration (control), hypercapnic stimulation elicited ventilatory augmentation in a hypercapnia intensity-dependent manner. Ventilatory parameters (tidal volume, frequency of respiration, and minute ventilation) showed significant increases from lower PaCO2 levels during aminophylline administration when compared with the corresponding values before aminophylline administration. EMG activity of both PARA and TA increased significantly at each level of hypercapnia, and those augmentations were shown from lower PaCO2 levels during aminophylline administration. CONCLUSION: Aminophylline administered at the usual clinical therapeutic dose increases ventilation and EMG activity of both inspiratory and expiratory muscles during hypercapnia in healthy humans.

[A Case Strongly Suspected of Being Pulmonary Toxocariasis Showing Multiple Pulmonary Nodules with a Disappearing and Reappearing Halo Sign].

We report herein on a case strongly suspected of being pulmonary toxocariasis. A 22-year-old Indonesian man referred to our hospital presented with abnormal chest shadows upon medical examination. He had no symptoms. He did not have any pets nor did he eat raw beef or chicken. Hematological examination revealed eosinophilia and elevation of IgE. Chest computed tomography revealed 3 pulmonary nodules with the halo sign. We suspected a parasite infection and performed antiparasite antibody testing. Ascaris suum was slightly positive on the screening test. As specific antibody against the larval excretory-secretory products of Toxocara canis, measured at the National Institute of Infectious Diseases, was positive (level 3 up to 8). Subsequently, the abnormal chest shadows disappeared. However, two months later, 2 pulmonary nodules with the halo sign reappeared in other places. Diagnostic therapy with albendazole was performed for 8 weeks. Mild hepatic impairment emerged during therapy, but it was within the allowed range. Thereafter, the results improved for the imaging findings, eosinophilia, serum IgE level, and specific antibody. The antibody level became negative two months after the treatment had ended. We should consider toxocariasis in the differential diagnosis of migratory nodular shadows with the halo sign on chest computed tomography, and immunoserological testing is useful for the diagnosis.

[Two Cases of Rapidly Progressive Community-acquired Pneumonia Due to Pseudomonas aeruginosa].

Pseudomonas aeruginosa is a significant causative bacterium in hospital-acquired pneumonia and nursing and healthcare-associated pneumonia, but it seems to be rare in community-acquired pneumonia (CAP). We report two cases of severe CAP due to P. aeruginosa. Case 1: A 52-year-old man was referred to our hospital for chest and back pain. He was being treated for diabetes mellitus and had a long history of smoking. Chest images showed consolidation in the right upper lobe. Soon after hospitalization, he developed sepsis shock and died seven hours later. Case 2: A 73-year-old man with a history of heavy smoking was referred to our hospital for right chest pain. Chest images showed right upper lobe pneumonia. Although wide-spectrum antimicrobial agents were administrated, he died ten hours after admission. In both cases, there was a rapid progression to death, despite administration of a broad spectrum of antibiotics and treatment for sepsis. In cases of CAP involving the right upper lobe, the possibility of bacteremia and rapid progress should be considered.

Comparison of the efficacy of gefitinib in patients with non-small cell lung cancer according to the type of epidermal growth factor receptor mutation.

BACKGROUND: Exon 19 deletion and L858R point mutation of the epidermal growth factor receptor (EGFR) are the most commonly encountered EGFR mutations in non-small cell lung cancer (NSCLC), and predict higher clinical outcomes following treatment with gefitinib. The objective of this study was to evaluate the differential clinical outcomes of gefitinib in patients with NSCLC according to the type of active EGFR mutation, i.e. exon 19 deletion or L858R point mutation. METHODS: We identified patients with advanced NSCLC harboring the exon 19 deletion or the L858R point mutation of EGFR who were on gefitinib treatment. The clinical outcomes were evaluated. RESULTS: Of the 124 patients with NSCLC harboring active EGFR mutations, the overall response rate, progression-free survival and overall survival were 60.5%, 11.3 and 27.3 months, respectively, and did not differ significantly between patients with the exon 19 deletion (61.8%, 11.3 and 32.2 months, respectively) and those with the L858R point mutation (58.9%, 9.0 and 27.7 months, respectively). CONCLUSION: It may be considered that there is no difference in the clinical efficacy of gefitinib between NSCLC patients who harbor the exon 19 deletion and those with the L858R point mutation.