Stratification of malignant pleural mesothelioma prognosis using recursive partitioning analysis.

PURPOSE: Prognostic factors and complicated prognostic models have been proposed for malignant pleural mesothelioma (MPM). This study was designed to stratify MPM prognosis by using a simple model. METHODS: Patients diagnosed with MPM in the past 10 years (n = 122) were examined retrospectively. Data on the presence of chest pain, performance status (PS), asbestos exposure, smoking status, white blood cell count (WBC), haemoglobin (Hb) concentration, platelet count (PLT), lactate dehydronate (LD), histology, stage, and date of death or censored status were collected. After the factors were examined in the univariate analysis, recursive partitioning analysis was performed. RESULTS: Statistically significant factors related to survival were the type of histology, stage, PS, WBC, PLT, Hb concentration, and LD. Histology, stage, PS, and Hb concentration were used in multivariate analysis. Stage and Hb concentration showed good statistical significance, whereas PS was borderline significant. The survival analyses were stratified into five groups by PS, stage, Hb concentration, and chest pain using recursive partitioning analysis. Group A comprised patients showing the most favourable prognoses (PS 0-2 and Hb concentration >12.1 g dL(-1) or PS 0-2 and Hb concentration ≤12.1 g dL(-1) without pain), and group B comprised the remaining patients. The median overall survival in groups A and B was 563 days (95 % confidence interval [CI] 502-779) and 157 days (95 % CI 115-224), respectively (hazard ratio of 5.44 [3.46-8.53, P < 0.0001]). CONCLUSIONS: The MPM patients with PS 0-2 and Hb concentration >12.1 or ≤12.1 g dL(-1) without chest pain had favourable prognoses.

The relationship between tyrosine kinase inhibitor therapy and overall survival in patients with non-small cell lung cancer carrying EGFR mutations.

For patients with epidermal growth factor receptor (EGFR) mutation-positive lung cancer, the relationship between the dose or duration of treatment with tyrosine kinase inhibitor (TKI) and overall survival remains unclear. Here, we analyzed clinical data of 39 patients who were diagnosed with EGFR mutation-positive non-small cell lung cancer and treated with TKI, but subsequently died. Several parameters were measured in this study: overall survival; first, second, and overall TKI therapy durations; first TKI intensity (actual dose/normal dose); and TKI rate (overall TKI therapy duration/overall survival). The response rate to TKI therapy was 50%, and the median survival was 553 days. After TKI therapy failed, 38.5% patients were re-challenged with TKI. We observed a moderate relationship [r = 0.534, 95% confidential interval (CI) = 0.263 to 0.727, P < 0.001] between overall TKI therapy duration and overall survival. However, we found no relationship between overall survival and first TKI intensity (r = 0.073, 95% CI = -0.380 to 0.247, P = 0.657) or TKI rate (r = 0.0345, 95% CI = -0.284 to 0.346, P = 0.835). Non-small cell lung cancer patients with mutation-positive tumors remained on TKI therapy for, on average, 33% of the overall survival time. These findings suggest that patients with EGFR mutation-positive tumors should not stick to using TKIs.

Role of Nrf2 in host defense against influenza virus in cigarette smoke-exposed mice.

Influenza virus is a common respiratory tract viral infection. Although influenza can be fatal in patients with chronic pulmonary diseases such as chronic obstructive pulmonary disease, its pathogenesis is not fully understood. The Nrf2-mediated antioxidant system is essential to protect the lungs from oxidative injury and inflammation. In the present study, we investigated the role of Nrf2 in protection against influenza virus-induced pulmonary inflammation after cigarette smoke exposure with both in vitro and in vivo approaches. For in vitro analyses, peritoneal macrophages isolated from wild-type and Nrf2-deficient mice were treated with poly(I:C) and/or cigarette smoke extract. For in vivo analysis, these mice were infected with influenza A virus with or without exposure to cigarette smoke. In Nrf2-deficient macrophages, NF-κB activation and the induction of its target inflammatory genes were enhanced after costimulation with cigarette smoke extract and poly(I:C) compared with wild-type macrophages. The induction of antioxidant genes was observed for the lungs of wild-type mice but not those of Nrf2-deficient mice after cigarette smoke exposure. Cigarette smoke-exposed Nrf2-deficient mice showed higher rates of mortality than did wild-type mice after influenza virus infection, with enhanced peribronchial inflammation, lung permeability damage, and mucus hypersecretion. Lung oxidant levels and NF-κB-mediated inflammatory gene expression in the lungs were also enhanced in Nrf2-deficient mice. Our data indicate that the antioxidant pathway controlled by Nrf2 is pivotal for protection against the development of influenza virus-induced pulmonary inflammation and injury under oxidative conditions.

Aggravation of bleomycin-induced pulmonary inflammation and fibrosis in mice lacking peroxiredoxin I.

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.

Nrf2 enhances cell proliferation and resistance to anticancer drugs in human lung cancer.

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 G(1) 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.

Gefitinib-sensitive EGFR lacking residues 746-750 exhibits hypophosphorylation at tyrosine residue 1045, hypoubiquitination, and impaired endocytosis.

Gefitinib-sensitive nonsmall cell lung cancers (NSCLC) are characterized by somatic mutations in the kinase domain of epidermal growth factor receptor (EGFR). The mutant EGFR forms are reported to mediate characteristic signal transduction pathways that are different from those mediated by the wild-type EGFR and are involved in transformation in vivo. We have examined signal transduction pathways initiated from a frequently identified gefitinib-sensitizing mutant EGFR lacking residues 746-750 by employing a mouse fibroblast cell line that is free of endogenous EGFR and transiently transfected COS-7 cells. Upon EGF stimulation, the deletion-mutant EGFR mediated prolonged downstream signals. The analysis of the phosphotyrosine patterns of the receptor revealed that the deletion-mutant EGFR lacked phosphorylation at tyrosine residue 1045, which is the major binding site of Cbl. The EGF-induced endocytosis of the deletion-mutant EGFR was impaired. The ubiquitination and downregulation of the deletion-mutant EGFR were also reduced. On the other hand, another mutant, EGFR, possessing a L858R substitution, exhibited phosphorylation at 1045 and its downstream signalings were not prolonged. These data suggest that the signal transduction pathways initiated from these mutant forms are different, and that impaired endocytosis might be responsible for the prolonged signals mediated by the deletion-mutant EGFR.

The gefitinib-sensitizing mutant epidermal growth factor receptor enables transformation of a mouse fibroblast cell line.

A specific inhibitor of the Epidermal Growth Factor Receptor (EGFR), Gefitinib, displays significant antitumor effects against non-small cell lung cancers (NSCLC) that express EGFR with mutations in their tyrosine kinase domain. Although previous reports have already demonstrated that oncogenic transformation can be induced by some mutant EGFR forms, the precise differences between mutant and wild-type EGFR in terms of mechanisms of transformation have not been fully elucidated. We show here that a murine fibroblast cell line, NR6 becomes transformed by an expression level of the mutant EGFR form lacking E746-A750 that is far less than that needed with transfected wild-type EGFR. However, the mutant EGFR was unable to transform NR6 in a ligand-independent manner, as was seen with the wild-type EGFR. The consequent biological features after transformation, including DNA synthesis or cell cycle progression and biochemical characteristics such as MAPK activation mediated by the mutant EGFR are comparable and equivalent to those mediated by wild-type EGFR. These data suggest that the mutant EGFR possesses greater ligand-dependent transformation when compared with wild-type EGFR, although the exact mechanisms to account for this characteristic remain to be defined.

[A case of adenocarcinoma of lung with idiopathic pulmonary fibrosis, showing 1 8-fluorodeoxyglucose uptake in positron emission tomograhy].

A 61-year-old man consulted our hospital because of bloody sputum. Cells of Class V (adenocarcinoma) were found on sputum cytologic examination. Chest computed tomography (CT) showed reticular shadows but no obvious mass was detected. Positron emission tomography with 18-fluorodeoxyglucose (FDG-PET) revealed FDG uptake in both lower lung fields and more increased FDG uptake in a small area of the left lung field. Repeated chest CT, bronchial brushing, bronchial washing, and lung-imaging fluorescence endoscopy were performed, however, resulting in no detection of the primary site of lung cancer. Six months after initial consultation, chest CT showed an enlargement of the shadow in left S6 corresponding to the area of the more increased FDG uptake in PET. On the other hand, the shadow in right S10 did not change in size. Bronchial brushing of the left S6 was performed again, and class IV cells (adenocarcinoma) were found. After left lower lobectomy, diagnoses of well differentiated adenocarcinoma and usual interstitial pneumonia (UIP) were established histologically. There has been no report demonstrating the efficacy of FDG-PET for diagnosis of lung cancer with idiopathic pulmonary fibrosis (IPF).However, combination of lung cancer should be considered if PET shows spots of high FDG uptake in the lung fields of IPF.

Relationship between progression-free survival and overall survival in patients with advanced non-small cell lung cancer treated with anticancer agents after first-line treatment failure.

AIM: The hazard ratio of progression-free survival (PFS-HR) generally does not reflect that of overall survival (OS-HR) in advanced non-small cell lung cancer (NSCLC) patients treated with first-line therapy. Short survival post-progression (SPP) better reflects the PFS-HR and OS-HR in simulations. We aimed to evaluate whether the PFS-HR reflects the OS-HR in NSCLC clinical trials for post-first-line treatments. METHOD: We reviewed clinical studies of post-first-line anticancer agents for NSCLC. We examined the sample size of the experimental arm (EA), median PFS (mPFS) or median time to progression in the EA, median overall survival (mOS) in the EA, the PFS-HR and the OS-HR. SPP was defined as the difference between mOS and mPFS. The association between mPFS and SPP, mPFS and mOS, and the PFS-HR and OS-HR was tested. We sought for the optimal point of correlation of PFS-HR and OS-HR by every 1 month of SPP. RESULTS: We identified 32 trials (34 arms). mPFS and mOS were weakly correlated (correlation coefficient [r] = 0.376; P = 0.0286). The PFS-HR and OS-HR were also moderately correlated (r = 0.415; P = 0.015). The maximum r value was 0.770 (SPP < 6 months; P < 0.0001) when we tested the associations between the PFS-HR and OS-HR for SPP using 1-month increments. The estimated regression equation at this point was OS-HR = 0.679 × (PFS-HR) + 0.349. CONCLUSION: The PFS-HR and OS-HR were strongly correlated in advanced NSCLC patients treated with post-first-line anticancer agents, with a SPP of less than 6 months.

[The salvage regimen for patients with advanced non-small cell lung cancer who failed prior chemotherapy: once-daily single oral agent Iressa].

BACKGROUND: To summarize the effect of Iressa for refractory patients with advanced non small cell lung cancer (NSCLC) failed to prior chemotherapy. METHODS: Thirty-one patients, with unresectable stage IIIB or IV NSCLC who had disease progression or relapse after prior chemotherapy using platinum-based regimen for at least 2 cycles, were admitted to the Osaka Prefectural Hobikino Hospital. Iressa 250 mg was administered once a day until disease progression was noted. Weekly chest x-ray and monthly CT scan were performed for response assessment each month. RESULTS: Among the 31 patients, one complete response (CR) and 7 partial responses (PR) were observed. CR rate was 3.2% (95% confidence interval: 0-17%), PR rate 22.6% (95% confidence interval: 10%-41%), disease control rate including both tumor responses and stable disease was 80.6% (95% confidence interval: 52%-92%). The rate of symptoms relieves was 51.6% (95% confidence interval: 33%-70%), the most effective symptoms being cough and pain. The median time to improved symptoms was 14 days. The most common adverse events were grade I or II skin rash and diarrhea which were readily manageable and reversible. No patients were withdrawn due to the adverse events CONCLUSIONS: Monotherapy using Iressa is effective and tolerable for the patients with advanced NSCLC who failed prior chemotherapy.

Important factors for achieving survival of five years or more in non-small cell lung cancer patients with distant metastasis.

In order to examine which factors were important for achieving a ≥5 year survival time in non-small cell lung cancer (NSCLC) patients with distant metastasis, 268 NSCLC patients who received first-line chemotherapy between January 2004 and December 2007 were retrospectively examined. The median survival time of the patients was 14 months, with 22 surviving for ≥5 years, 48 for ≥2 years, but <5 years, and 198 surviving <2 years. Multivariate analysis determined that never having smoked, a good performance status, relapse following thoracic surgery and intra-thoracic metastasis were significantly favorable prognostic factors, while abdominal metastasis was a significantly poor prognostic factor. The ≥5 years and ≥2-5 years groups had significantly more favorable prognostic factors than the <2 years group. The never-smoked status was a particularly important factor for ≥5 years of survival. The ≥5 years and ≥2-5 years groups achieved a significantly more favorable response to first-line chemotherapy, and a greater number of regimens, total months of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) treatment and cytotoxic agent treatment cycles compared with the <2 years group. In total, ~50% of the patients received palliative radiotherapy. In the ≥5 years group, patients with EGFR drug-sensitive mutations achieved ≥5 years of survival mainly by EGFR-TKI therapy, while those without EGFR mutations achieved ≥5 years of survival by continuing effective cytotoxic agents. Achievement of >5 years of survival was found to correlate with the presence of favorable prognostic factors, response to first-line chemotherapy, provision of appropriate EGFR-TKI therapy according to genetic testing results, continuing effective cytotoxic regimens and the use of radiotherapy as local therapy.

Usefulness of high suction pressure for sufficient tissue collection during endobronchial ultrasound guided transbronchial needle aspiration.

INTRODUCTION: The optimal suction pressure during endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) remains to be determined. The aim of this study was to compare suction pressures for performance in collecting sufficient tissue specimens from mediastinal and hilar lymph nodes during EBUS-TBNA. METHODS: Retrospective analysis of consecutive patients with mediastinal and hilar lymphadenopathy who underwent EBUS-TBNA over a 3-year period. Results from patients who underwent EBUS-TBNA using a dedicated 20-mL VacLoc (Merit Medical Systems, Inc, South Jordan, UT) syringe (conventional method, group C) were compared with results from patients in whom a disposable 30-mL syringe (high pressure group, group H) was used. The yield for sufficient histologic specimen retrieval and amount of tissue obtained were compared between the 2 groups. RESULTS: Of 178 patients who underwent EBUS-TBNA, 131 had lung cancer confirmed by EBUS-TBNA: 35 in group C and 96 in group H. There were 7 patients in group C and 6 in group H who received final diagnoses by cytology alone. There were 28 in group C and 90 in group H who were diagnosed by both cytology and histology. There was a statistically significant difference between the groups in terms of the rate of sufficient sampling for histological specimens (p = 0.04). The H group revealed a tissue area approximately twice that of the C group (p = 0.003). There were no major procedure-related complications in either group. CONCLUSION: Higher suction pressures with larger syringe volumes during EBUS-TBNA may be useful for safely collecting sufficient tissue specimens.

Phase2 study of bevacizumab with carboplatin-paclitaxel for non-small cell lung cancer with malignant pleural effusion.

Vascular endothelial growth factor (VEGF) is involved in non-small cell lung cancer (NSCLC) with malignant pleural effusion (MPE), but little is known regarding the efficacy of bevacizumab (Bev) with carboplatin-paclitaxel (CP) for NSCLC with MPE. Chemotherapy-naive non-SQ NSCLC patients with MPE were eligible to participate. Pleurodesis before chemotherapy was not allowed. In the first cycle, the treated patients received only CP to prevent Bev-induced wound healing delayed after chest drainage. Subsequently, they received 2-6 cycles of CP with Bev. Patients who completed more than 4 cycles of CP and Bev without disease progression or severe toxicities continued to receive Bev alone as a maintenance therapy. The primary end point was overall response, although an increase in MPE was allowed in the first cycle. The VEGF levels in plasma and MPE were measured at baseline, and the VEGF levels in plasma were measured after 3 cycles of chemotherapy. Between September 2010 and June 2012, 23 patients were enrolled. The overall response rate was 60.8 %; the disease control rate was 87.0 %. Sixteen patients received maintenance therapy, following a median of 3 cycles. Median progression-free and overall survival times were 7.1 months (95 % confidence interval [CI], 5.6-9.4 months) and 11.7 months (95 % CI, 7.4-16.8 months), respectively. Most patients experienced severe hematological toxicities, including ≥grade 3 neutropenia; none experienced severe bleeding events. The MPE control rate improved on combining CP with Bev (CP, 78.3 %; CP with Bev, 91.3 %; P = 0.08). The median baseline VEGF level in MPE was 1798.6 (range 223.4-35,633.4) pg/mL. Plasma VEGF levels significantly decreased after 3 chemotherapy cycles (baseline, 513.6 ± 326.4 pg/mL, post-chemotherapy, 25.1 ± 14.1 pg/mL, P < 0.01). CP plus Bev was effective and tolerable in chemotherapy-naïve non-squamous NSCLC patients with MPE.