Granulocyte colony-stimulating factor has the potential to attenuate the therapeutic efficacy of chemo-immunotherapy for extensive-stage small-cell lung cancer.

BACKGROUND: Granulocyte colony-stimulating factor (G-CSF) has the potential to attenuate the anti-tumor immune responses of T-cells by increasing immune suppressive neutrophils and myeloid-derived suppressor cells. However, the clinical impact of G-CSF on the efficacy of immunotherapy remains unknown. This multi-center retrospective analysis evaluated the impact of G-CSF in patients with extensive-stage small-cell lung cancer (ES-SCLC) treated with chemo-immunotherapy. METHODS: We analyzed 65 patients with ES-SCLC who completed four cycles of induction chemo-immunotherapy and evaluated the effects of G-CSF on progression-free survival (PFS), overall survival (OS), and a durable response to immunotherapy (defined as PFS ≥ 12 months). RESULTS: Fifty patients (76.9%) received ≥ 1 dose of G-CSF. The PFS of the patients with G-CSF was poorer than that of the patients without G-CSF (median PFS 8.3 vs. 4.9 months, p = 0.009). The OS of the patients with G-CSF tended to be shorter, but not statistically significant, than that of the patients without G-CSF (median OS 24.3 vs. 16.4 months, p = 0.137). In the multivariate analysis, G-CSF administration was associated with poorer PFS (hazard ratio 2.78, 95% CI 1.36-5.69, p = 0.005) and was identified as a determinant of a durable response (odds ratio 0.18, 95% CI 0.04-0.80, p = 0.024). These results were consistent with other definitions of G-CSF administration (administration of ≥ 1 dose of pegfilgrastim, or either ≥ 5 doses of filgrastim or ≥ 1 dose of pegfilgrastim). CONCLUSIONS: G-CSF has the potential to attenuate the efficacy of immunotherapy; therefore, the indication for G-CSF during chemo-immunotherapy should be carefully considered for ES-SCLC.

A Case of Autoimmune Pulmonary Alveolar Proteinosis With Predominantly Peripheral Opacities Diagnosed by Transbronchial Lung Biopsy.

Although pulmonary alveolar proteinosis (PAP) showed various shadows, its shadows are usually distributed predominantly in the central lung area. We report a case of autoimmune PAP with localized subpleural ground-glass shadows in the bilateral upper lobes, which was diagnosed based on transbronchial lung biopsy (TBLB) specimen findings and anti-granulocyte macrophage colony PAP stimulating factor antibody positivity. PAP should be listed as a differential diagnosis for subpleural shadows. If subpleural shadows are observed, TBLB should be performed aggressively, and anti-granulocyte macrophage colony-stimulating factor (anti-GM-CSF) antibodies should be submitted.

Two Cases of Mycobacterium shinjukuense Pulmonary Disease With a Long-Term Response to Treatment With Clarithromycin, Rifampicin, and Ethambutol.

Mycobacterium shinjukuense is a nontuberculous mycobacterium, and standard treatment for the infection has not been established. We report two cases of M. shinjukuense pulmonary disease in which two patients were treated with clarithromycin (CAM), rifampicin (RFP), and ethambutol (EB). Based on computed tomography (CT) findings, the patients experienced improvement with treatment. Reports of multiple cases of M. shinjukuense pulmonary disease treated with clarithromycin, rifampicin, and ethambutol are valuable, and they suggest that this regimen may be a new treatment option.

Study on the Optimal Dose of Irinotecan for Patients with Heterozygous Uridine Diphosphate-Glucuronosyltransferase 1A1 (UGT1A1).

Uridine 5'-diphospho-glucuronosyltransferase (UGT), a metabolic enzyme of irinotecan active metabolite, has two genetic polymorphisms (UGT1A1*6 and UGT1A1*28). In UGT1A1 homozygous or heterozygous patients, metabolism is delayed and the risk of developing adverse effects is increased, and therefore, dose reduction of irinotecan is considered. However, the specific dose reduction rate of irinotecan for heterozygous patients is uncertain. We studied the necessity of irinotecan dose reduction and its optimal dose in UGT1A1 heterozygous patients with lung cancer. Patients with lung cancer treated with irinotecan in the Tokushima University Hospital or Tokushima Municipal Hospital were included in this study. The dose of irinotecan was evaluated based on the relative dose intensity (RDI). The time to treatment failure (TTF) was defined as the period until treatment change, death, or progressive disease based on response evaluation criteria of solid tumors. We targeted 31 patients treated with irinotecan: 12 wild types (WT), 14 heterozygotes, and 1 complex heterozygote and 4 homozygotes. There was no significant difference in the TTF, but the mean RDI during the entire treatment period was significantly different in the wild type (79%), heterozygous (62%), and complex heterozygous and homozygous groups (46%). In addition, the proportion of patients who completed treatment without dose reduction in the WT group tended to be higher than that in the other groups. For lung cancer patients with UGT1A1 heterozygote types who start irinotecan therapy, reducing the initial dose by approximately 20% might be a safer chemotherapy without decreasing the therapeutic effect.

The clinical features of older patients with lung cancer in comparison with their younger counterparts.

BACKGROUND: Older patients with lung cancer have increased over the past decades. Several standard treatments for older patients were established, but their clinical features in real world clinics remain unknown. Thus, we performed a retrospective study to clarify the clinical features of them. METHODS: The patients with lung cancer who were admitted to our hospital between April 1, 2012 and March 31, 2015 were retrospectively analyzed. Patients older than 75 years were defined as older patients. Standard treatments were based on the guidelines. RESULTS: In total, 333 patients were analyzed. The older patients had a poor performance status (PS), more comorbidities, and fewer opportunities to receive standard treatments. The prognosis of the older patients who received standard treatments was superior to that of those who did not. The therapeutic efficacy of standard treatments for older patients with stages I and II diseases was similar to their younger counterparts. However, the prognosis of older patients with advanced stage, especially stage III disease, was poor. The tolerability of first-line chemotherapy by older patients was comparable with their younger counterparts, but the older patients had fewer opportunities to receive several chemotherapy regimens, even second line chemotherapy. CONCLUSIONS: We should positively consider standard treatments for older patients. However, not only their shorter life expectancy but also their poor PS and multiple comorbidities that sometimes render patients unable to receive standard treatments and several chemotherapy regimens, make their prognosis poor. The standard treatments for older patients, especially in locally advanced stages, require modification.

A multicenter, open-label, phase II trial of S-1 plus carboplatin in advanced non-small cell lung cancer patients with interstitial lung disease.

OBJECTIVES: The clinical benefit of chemotherapy and the appropriate regimen for non-small-cell lung cancer (NSCLC) patients with interstitial lung disease (ILD) remain unclear. To fulfill this unmet medical need, we conducted a phase II study to elucidate the efficacy of S-1 in combination with carboplatin (CBDCA) in NSCLC patients with ILD. MATERIALS AND METHODS: A total of 33 advanced or recurrent NSCLC patients with ILD were prospectively enrolled in this multicenter, open-label, phase II study. Every 4 weeks, CBDCA at a dose of AUC 5 on day 1 and S-1 at a dose of 80 mg/m2 daily for 14 days were administered. The primary endpoint was the investigator-assessed objective response rate. RESULTS: The median age at initiating chemotherapy was 70. Sixteen patients (48.5%) had squamous cell carcinoma histology. With respect to the types of ILD, the usual interstitial pneumonia pattern was dominant (66.7%). The median number of cycles administered was 3, and the overall response rate and disease control rate were 33.3% and 78.8%, respectively. The median progression-free survival, the median survival time and the 1-year survival rate were 4.8 months, 12.8 months and 51.4%, respectively. Acute exacerbation of ILD caused by chemotherapy was noted in 2 patients (6.1%). CONCLUSION: This is the first prospective study designed to evaluate the efficacy of a specific chemotherapeutic regimen as the primary endpoint in patients with advanced NSCLC with ILD. The combination of S-1 with CBDCA may be a treatment option for advanced NSCLC patients with ILD (The clinical trial registration number: UMIN000011046).

Phase II study of tailored S-1 monotherapy with a 1-week interval after a 2-week dosing period in elderly patients with advanced non-small cell lung cancer.

BACKGROUND: S-1 is an oral fluoropyrimidine that is active in the treatment of non-small cell lung cancer (NSCLC); however, an optimal treatment schedule and appropriate dose adjustments of S-1 in elderly patients have not yet been established. METHODS: We conducted a phase II trial to evaluate the efficacy and safety of a 2-week S-1 monotherapy treatment followed by a 1-week interval as a first-line treatment of elderly NSCLC patients, by adjusting the dose based on the individual creatinine clearance (Ccr) and body surface area (BSA). The primary endpoint was the disease control rate. RESULTS: Forty patients were enrolled. The disease control and response rates were 89.5% (95% confidence interval [CI] = 79.8-99.2) and 7.9% (95% CI = 0.0-16.4), respectively. The median progression-free survival and overall survival times were 4.4 months (95% CI = 4.2-8.5) and 17.0 months (95% CI = 11.2-18.7), respectively. Neutropenia, anorexia, hyponatremia, hypokalemia, and pneumonia of grade ≥ 3 occurred in 5.0%, 7.5%, 5.0%, 2.5%, and 2.5% of patients, respectively. Among the patient-reported outcomes, most of the individual factors in the patients' quality of life, including upper intestine-related symptoms improved with the treatment, except for dyspnea, which slightly albeit continuously worsened throughout the study. CONCLUSIONS: In elderly patients with previously untreated advanced NSCLC, a 2-week S-1 monotherapy treatment, tailored to both the Ccr and BSA, with a 1-week interval was well tolerated and demonstrated promising efficacy. This study was registered at the University Hospital Medical Information Network (UMIN) Center (ID: UMIN000002035), Japan.

Analysis of acute exacerbation of interstitial lung disease associated with chemotherapy in patients with lung cancer: A feasibility of S-1.

BACKGROUND: Interstitial lung disease (ILD) is commonly concomitant with lung cancer, and its acute exacerbation (AE) is the most serious complication in patients receiving treatment for lung cancer. METHODS: To investigate the incidence and characteristic features of AE of ILD, we conducted a retrospective study of 665 consecutive patients with lung cancer who were treated at our institute between 2008 and 2014. RESULTS: Among the 665 patients, 74 (11.1%) had preexisting ILD, and 64 of them received chemotherapy. Four of the 64 patients (6.3%) had experienced AE of ILD, and two (3.1%) died of respiratory failure during first-line chemotherapy. The use of a combination of carboplatin with tegafur-gimeracil-oteracil potassium (S-1) or paclitaxel as a first-line chemotherapy for non-small cell lung cancer led to a lower frequency of AE, at 8.3% (1/12) and 9.1% (1/11), respectively. The incidence of AE rose to 12.8% (5/39) during second-line treatment, and 14 (total: 15 times) of the 64 patients (21.9%) experienced AE from the time of diagnosis to the end of treatment. The incidence of AE was 17.7% (6/34), 15.8% (3/19), 5.0% (2/40), and 4.2% (1/24) in the paclitaxel-, vinorelbine-, etoposide-, and S-1-containing regimens, respectively. No difference in clinical features and laboratory data was detected between the AE and non-AE groups. CONCLUSIONS: Although this was a small retrospective study, its findings showed that S-1 and etoposide may be relatively safe options for the treatment of patients with lung cancer and concomitant ILD.

Analysis of the Prognostic Factors of Extensive Disease Small-Cell Lung Cancer Patients in Tokushima University Hospital.

BACKGROUND: Small-cell lung cancer (SCLC) presents aggressive clinical behavior, and its prognosis is still poor. Previously, performance status (PS), or the existence of brain, bone, or liver metastasis were reported to be unfavorable prognostic factors. Given the recent progress of treatment modalities such as radiotherapy techniques and bone modifying agents, the prognostic factors might be different from previous findings. Therefore, we analyzed the prognostic factors of extensive disease SCLC (ED-SCLC) in recent years. METHODS: ED-SCLC patients treated in Tokushima University Hospital between 2010 and 2016 were analyzed. Log-rank test and the Cox proportional hazards regression model was used in univariate and multivariate analysis, respectively. RESULTS: Totally, 79 patients were analyzed. In the univariate analysis, age, PS, interstitial pneumonia (IP), liver metastasis, pleural dissemination, neutrophil counts, hypoalbuminemia, hypercalcemia and several liver and biliary enzymes were identified as poor prognostic factors. In the multivariate analysis, age, PS, IP, and liver and biliary enzymes were identified. Moreover, the PS in patients with liver metastasis was significantly worsened. CONCLUSIONS: In this study, we newly demonstrated that IP was a significant poor prognostic factor of ED-SCLC. Although liver metastasis was not extracted in multivariate analysis, it may have an impact on the prognosis of ED-SCLC. J. Med. Invest. 63: 286-293, August, 2016.

Fibrocyte-like cells mediate acquired resistance to anti-angiogenic therapy with bevacizumab.

Bevacizumab exerts anti-angiogenic effects in cancer patients by inhibiting vascular endothelial growth factor (VEGF). However, its use is still limited due to the development of resistance to the treatment. Such resistance can be regulated by various factors, although the underlying mechanisms remain incompletely understood. Here we show that bone marrow-derived fibrocyte-like cells, defined as alpha-1 type I collagen-positive and CXCR4-positive cells, contribute to the acquired resistance to bevacizumab. In mouse models of malignant pleural mesothelioma and lung cancer, fibrocyte-like cells mediate the resistance to bevacizumab as the main producer of fibroblast growth factor 2. In clinical specimens of lung cancer, the number of fibrocyte-like cells is significantly increased in bevacizumab-treated tumours, and correlates with the number of treatment cycles, as well as CD31-positive vessels. Our results identify fibrocyte-like cells as a promising cell biomarker and a potential therapeutic target to overcome resistance to anti-VEGF therapy.

Pemetrexed-Induced Rash May Be Prevented by Supplementary Corticosteroids.

Pemetrexed, a chemotherapeutic drug, is highly active in non-small cell lung cancer and malignant pleural mesothelioma. Unfortunately, rashes are more commonly associated with pemetrexed than other chemotherapies, and it is recommended that patients receive corticosteroids (8 mg/d of dexamethasone) for 3 d, including the day of pemetrexed administration (day 1). However, the efficacy of corticosteroids in this context has not been fully verified. In this retrospective study, we evaluated the medical records of 78 patients who received pemetrexed between April 2009 and March 2014, to confirm whether supplementary corticosteroids prevented rash development. The incidence of rash was lower in the 47 patients who received supplementary corticosteroids (after day 1) compared with the incidence among the 31 patients who did not receive supplementary corticosteroids (19.1% vs. 38.7%). The average cutoff dosage of supplementary corticosteroids on day 2 and day 3 was 1.5 mg/d of dexamethasone, as calculated using the receiver operating characteristic curve, and the odds ratio was 0.33 (95% confidence interval: 0.12-0.94). Administration of ≥1.5 mg of corticosteroids on day 2 and day 3 significantly reduced the severity of the rash compared to no supplementary treatment (grades 2/3, 13.3% vs. 33.3%, p<0.05). However, increasing the dose of corticosteroids had no additional effect on rash development. These results suggest that ≥1.5 mg of supplementary dexamethasone on day 2 and day 3 (in addition to day 1) may be necessary for preventing pemetrexed-induced rash, but high doses of dexamethasone (e.g., 8 mg/d) are unnecessary.

Characteristics of and risk factors for interstitial lung disease induced by chemotherapy for lung cancer.

BACKGROUND: Drug-induced interstitial lung disease (DILD) is generally a serious adverse effect and almost always necessitates the discontinuation of the offending drug. Cancer pharmacotherapy is strongly associated with DILD, and the risk of DILD has been suggested to be higher in patients with lung cancer because of preexisting pneumonic disease. OBJECTIVE: The aim of this retrospective study was to identify the risk factors and prognostic factors for early death from interstitial lung disease (ILD) induced by chemotherapy for lung cancer. METHODS: The medical records of 459 patients who underwent chemotherapy for lung cancer between April 2007 and March 2013 were analyzed with regard to patient background and DILD development, initial symptoms, and prognosis. RESULTS: A total of 33 patients (7.2%) developed chemotherapy-induced ILD. The most frequently observed initial symptom was dyspnea (94.3%). Preexisting ILD was identified as a risk factor for DILD (odds ratio [OR] = 5.38; 95% CI = 2.47-11.73; P < 0.01). Among the 33 patients who developed DILD, 10 patients suffered an early death despite steroid therapy. Poor prognostic factors included epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) use (OR = 9.26; 95% CI = 1.05-82.0; P < 0.05) and 2 or more prior chemotherapy regimens (OR = 6.95; 95% CI = 1.14-42.3; P < 0.05). CONCLUSIONS: Many lung cancer patients have coexisting ILD, and these patients have a high risk of developing chemotherapy-induced ILD. In addition, patients with DILD who underwent EGFR-TKI therapy and 2 or more prior chemotherapy regimens had a higher risk of fatal outcome.

Identification of pregnancy-associated plasma protein A as a migration-promoting gene in malignant pleural mesothelioma cells: a potential therapeutic target.

Despite recent advances in treatment, malignant pleural mesothelioma (MPM) remains a deadly disease. Targeted therapy generated broad interests and is highly expected for the treatment of MPM, yet promising preclinical results have not been translated into substantial clinical benefits for the patients. In this study, we tried to identify the genes which play functional roles in cell migration as well as to test whether they can be used as novel targets for molecular targeted therapy for MPM in preclinical model. In our study, pregnancy-associated plasma protein A (PAPPA) was identified as a gene whose expression level is correlated with MPM cell migration by correlation analysis combining MPM cell migration ability and their gene expression profiles. Highly migratory cells were selected from MPM cell lines, MSTO-211H, NCI-H290 and EHMES-1 in vitro and up-regulation of PAPPA in these cells were confirmed. In vitro, PAPPA was demonstrated to stimulate the MPM cell migration via cleavage of insulin-like growth factor-binding protein-4 and subsequent release of IGF-1. Gene silencing of PAPPA in MPM cells led to reduced migration, invasion and proliferation. Furthermore, PAPPA shRNA transfected NCI-H290 when orthotopically inoculated into pleural cavity of severe combined immunodeficiency recipient mice, failed to develop tumors and produce bloody pleural effusion as control shRNA transfected cells did. Our study suggests that PAPPA plays a functional role in promoting MPM cell migration and it might serve as a potential therapeutic target for the treatment of MPM.

A novel targeting therapy of malignant mesothelioma using anti-podoplanin antibody.

Podoplanin (Aggrus), which is a type I transmembrane sialomucin-like glycoprotein, is highly expressed in malignant pleural mesothelioma (MPM). We previously reported the generation of a rat anti-human podoplanin Ab, NZ-1, which inhibited podoplanin-induced platelet aggregation and hematogenous metastasis. In this study, we examined the antitumor effector functions of NZ-1 and NZ-8, a novel rat-human chimeric Ab generated from NZ-1 including Ab-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity against MPM in vitro and in vivo. Immunostaining with NZ-1 showed the expression of podoplanin in 73% (11 out of 15) of MPM cell lines and 92% (33 out of 36) of malignant mesothelioma tissues. NZ-1 could induce potent ADCC against podoplanin-positive MPM cells mediated by rat NK (CD161a(+)) cells, but not murine splenocytes or human mononuclear cells. Treatment with NZ-1 significantly reduced the growth of s.c. established tumors of MPM cells (ACC-MESO-4 or podoplanin-transfected MSTO-211H) in SCID mice, only when NZ-1 was administered with rat NK cells. In in vivo imaging, NZ-1 efficiently accumulated to xenograft of MPM, and its accumulation continued for 3 wk after systemic administration. Furthermore, NZ-8 preferentially recognized podoplanin expressing in MPM, but not in normal tissues. NZ-8 could induce higher ADCC mediated by human NK cells and complement-dependent cytotoxicity as compared with NZ-1. Treatment with NZ-8 and human NK cells significantly inhibited the growth of MPM cells in vivo. These results strongly suggest that targeting therapy to podoplanin with therapeutic Abs (i.e., NZ-8) derived from NZ-1 might be useful as a novel immunotherapy against MPM.

Surfactant protein A suppresses lung cancer progression by regulating the polarization of tumor-associated macrophages.

Surfactant protein A (SP-A) is a large multimeric protein found in the lungs. In addition to its immunoregulatory function in infectious respiratory diseases, SP-A is also used as a marker of lung adenocarcinoma. Despite the finding that SP-A expression levels in cancer cells has a relationship with patient prognosis, the function of SP-A in lung cancer progression is unknown. We investigated the role of SP-A in lung cancer progression by introducing the SP-A gene into human lung adenocarcinoma cell lines. SP-A gene transduction suppressed the progression of tumor in subcutaneous xenograft or lung metastasis mouse models. Immunohistochemical analysis showed that the number of M1 antitumor tumor-associated macrophages (TAMs) was increased and the number of M2 tumor-promoting TAMs was not changed in the tumor tissue produced by SP-A-expressing cells. In addition, natural killer (NK) cells were also increased and activated in the SP-A-expressing tumor. Moreover, SP-A did not inhibit tumor progression in mice depleted of NK cells. Taking into account that SP-A did not directly activate NK cells, these results suggest that SP-A inhibited lung cancer progression by recruiting and activating NK cells via controlling the polarization of TAMs.

Macrophage stimulating protein promotes liver metastases of small cell lung cancer cells by affecting the organ microenvironment.

The organ microenvironment significantly affects the processes of cancer metastasis. Elucidating the molecular mechanisms of interaction between tumor cells and the organ microenvironment is crucial for the development of effective therapeutic strategies to eradicate cancer metastases. Macrophage stimulating protein (MSP), an activator of macrophages, regulates a pleiotropic array of effects, including proliferation, cellular motility, invasiveness, angiogenesis, and resistance to anoikis. However, the role of MSP in cancer metastasis is still largely unknown. In this study, the action of MSP on the production of metastases was determined in a multiple-organ metastasis model. The murine MSP gene was transfected into two human SCLC cell lines, SBC-5 and H1048, to establish transfectants secreting biologically active MSP. MSP gene transduction did not affect cell proliferation and motility in vitro. Intravenously inoculated MSP transfectants produced significantly larger numbers of liver metastases than parental cells or vector control clones, while there were no significant differences in bone or lung metastases among them. Immunohistochemical analyses of liver metastases revealed that tumor-associated microvessel density and tumor-infiltrating macrophages were significantly increased in lesions produced by MSP transfectants. MSP could stimulate the migration of murine macrophages and endothelial cells in vitro. Consequently, MSP may be one of the major determinants that affects the properties of tumor stroma and that produces a permissive microenvironment to promote cancer metastasis.

Dll4-Fc, an inhibitor of Dll4-notch signaling, suppresses liver metastasis of small cell lung cancer cells through the downregulation of the NF-κB activity.

Notch signaling regulates cell-fate decisions during development and postnatal life. Little is known, however, about the role of Delta-like-4 (Dll4)-Notch signaling between cancer cells, or how this signaling affects cancer metastasis. We, therefore, assessed the role of Dll4-Notch signaling in cancer metastasis. We generated a soluble Dll4 fused to the IgG1 constant region (Dll4-Fc) that acts as a blocker of Dll4-Notch signaling and introduced it into human small cell lung cancer (SCLC) cell lines expressing either high levels (SBC-3 and H1048) or low levels (SBC-5) of Dll4. The effects of Dll4-Fc on metastasis of SCLC were evaluated using a mouse model. Although Dll4-Fc had no effect on the liver metastasis of SBC-5, the number of liver metastasis inoculated with SBC-3 and H1048 cells expressing Dll4-Fc was significantly lower than that injected with control cells. To study the molecular mechanisms of the effects of Dll4-Fc on liver metastasis, a PCR array analysis was conducted. Because the expression of NF-κB target genes was affected by Dll4-Fc, we conducted an electrophoretic mobility shift assay and observed that NF-κB activities, both with and without stimulation by TNF-α, were downregulated in Dll4-Fc-overexpressing SBC-3 and H1048 cells compared with control cells. Moreover, Dll4-Fc attenuates, at least in part, the classical and alternative NF-κB activation pathway by reducing Notch1 signaling. These results suggest that Dll4-Notch signaling in cancer cells plays a critical role in liver metastasis of SCLC by regulating NF-κB signaling.

SU6668, a multiple tyrosine kinase inhibitor, inhibits progression of human malignant pleural mesothelioma in an orthotopic model.

BACKGROUND AND OBJECTIVE: Malignant pleural mesothelioma (MPM) is an aggressive neoplasm of the mesothelium with high chemotherapeutic resistance. In this study, the preclinical therapeutic activity of the multiple tyrosine kinase inhibitor, SU6668, against MPM was examined. METHODS: Two human MPM cell lines with different pro-angiogenic cytokine expression, Y-MESO-14 cells that express high levels of vascular endothelial growth factor (VEGF) and MSTO-211H cells that express high levels of basic fibroblast growth factor (bFGF), were orthotopically inoculated into the thoracic cavities of mice with severe combined immunodeficiency. The mice with MPM were treated or not treated with SU6668 (200 mg/kg/day). RESULTS: SU6668 abrogated the proliferation of endothelial cells stimulated by VEGF or bFGF, but did not directly affect the growth of human MPM cells in vitro. In this orthotopic implantation model, treatment with SU6668 effectively reduced tumour weight and pleural effusion volumes, in association with inhibition of the growth of tumour vasculature. More importantly, treatment with SU6668 significantly prolonged survival time in mice with MPM. CONCLUSIONS: These findings suggest that SU6668 has a promising therapeutic effect on the progression of MPM in vivo through its anti-angiogenic effects.

Epidermal growth factor receptor-tyrosine kinase inhibitor (gefitinib) augments pneumonitis, but attenuates lung fibrosis in response to radiation injury in rats.

BACKGROUND: Gefitinib, an inhibitor of epidermal growth factor receptor (EGFR) tyrosine kinase, has been reported to be associated with interstitial lung disorders, and their high incidence and mortality have become a matter of great concern, especially in Japan. In this study, we investigated the effect of gefitinib on different phases of radiation-induced lung disorders in an experimental model. METHODS: The thoraxes of Wistar rats were irradiated on day 1 with a single X-ray dose of 20 Gy, and gefitinib (50 mg/kg/day) was orally administered from day 1 to 14. The rat lungs were harvested on days 15 and 57 and the bronchoalveolar lavage (BAL) was performed. RESULTS: Gefitinib treatment increased the infiltration of inflammatory cells, which produced more pro-inflammatory cytokines (IL-6, IL-1ß), in the lungs of the irradiated rats on days 15 and 57, while gefitinib treatment reduced collagen content of the lungs in irradiated rats and decreased proliferation and EGFR expression in the lung fibroblasts from irradiated rats on day 57. CONCLUSIONS: In irradiated rats, gefitinib treatment augmented lung inflammation, including inflammatory cell infiltration and pro-inflammatory cytokine expression, while gefitinib treatment attenuated fibrotic lung remodeling due to the inhibition of lung fibroblast proliferation.

Identification of genes potentially involved in bone metastasis by genome-wide gene expression profile analysis of non-small cell lung cancer in mice.

Lung cancer is commonly associated with multi-organ metastasis, and the bone is a frequent metastatic site for lung cancer. However, the molecular mechanism of organ-specific metastasis remains poorly understood. To elucidate this issue, we analyzed in this study genome-wide gene expression profiles of 15 metastatic lesions from three organs (bone, lung and liver) in a mouse model with multi-organ metastasis properties of human non-small cell lung cancer cells (ACC-LC319/bone2), using a combination of laser-microbeam microdissection and DNA microarrays. We identified 299 genes that could potentially be involved in the organ-selective nature of lung cancer metastasis. Among them, 77 were bone-specifically expressed elements, including genes involved in cell adhesion, cytoskeleton/cell motility, extracellular matrix remodeling and cell-cell signaling as well as genes already known to be involved in the bone metastasis of breast cancers. Quantitative RT-PCR confirmed the specific upregulation of eight genes in bone metastasis tumors, suggesting that these genes may be involved in bone metastasis. Our findings should be helpful for a better understanding of the molecular aspects of the metastatic process in different organs, and could lead to molecular target-based anticancer drugs and prevention of metastasis, especially bone metastasis.