Abstract 4679: Novel pathway mutations in malignant mesothelioma revealed by high-throughput DNA and RNA sequencing

Background: Malignant mesothelioma (MM) is an aggressive neoplasm associated with asbestos exposure. Because MM is usually diagnosed at an advanced stage and is largely unresponsive to conventional therapy, it is necessary to identify the signal pathways driving MM and to develop therapeutics specifically targeting these pathways.

Materials and Methods: We carried out RNA sequencing of 12 MM cell lines and 4 clinical samples and exome sequencing of 6 MM cells using a so-called next-generation sequencer. We further performed pathway-targeted genome sequencing of 23 paired samples of MM tumor and normal tissue.

Results: We identified 15 novel fusion genes by RNA sequencing and confirmed them by conventional Sanger sequencing and FISH analyses. We showed that the novel gene was included in both LOH and a fusion gene, and the gene which was critical tumor-suppressor roles caused two hit and was down-regulated. The gene has been identified as a central player of the emerging signaling pathway. We further identified the accumulation of mutations in 35% of the MMs by pathway-targeted genome sequencing.

Conclusions: We indicated the need for the discovering molecular targets in the novel pathway in MMs. Our findings provide novel insights into the pathogenesis of MM and unequivocally demonstrate the power of sequencing technologies in cancer research.

Citation Format: Akihiko Miyanaga, Mari Masuda, Koji Tsuta, Yuka Nakamura, Hisao Asamura, Akihiko Gemma, Tesshi Yamada. Novel pathway mutations in malignant mesothelioma revealed by high-throughput DNA and RNA sequencing. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4679. doi:10.1158/1538-7445.AM2014-4679

Abstract 4062: Nestin regulates proliferation, migration, invasion and stemness of lung adenocarcinoma

Lung cancer is the most common cancer and the most common cause of cancer-related death in the world. Despite of the therapeutic advances in the treatment of non-small cell lung cancer (NSCLC) including molecular targeted therapy for lung adenocarcinoma (AD), the prognosis of the patients with NSCLC is dismal. Therefore, new treatment strategies are needed. Nestin, a class VI intermediate filament, is known to be a cancer stem cell (CSC) marker as well as a neuroepithelial stem cell marker. High expression levels of nestin are reported in various malignant tumors including lung, pancreas, cervical and prostate cancers, malignant melanomas and glioblastomas. Nestin is thought to regulate tumor cell proliferation, migration, invasion and CSC properties. Here we confirmed nestin expression in NSCLC: Immunohistochemical analysis in surgical specimens detected nestin protein expression in the cytoplasm of 20 of 48 AD cases (41.7%) and 25 of 47 squamous cell carcinoma cases (53.2%). Nestin immunoreactivity significantly correlated with not only tumor size and lymph node metastasis in NSCLC (p = 0.02, for both), but also poor survival in surgical patients with AD (p = 0.02). High and moderate expression levels of nestin were confirmed in several lung AD cell lines including H1975 and PC-3. Nestin inhibition by short hairpin RNA (shRNA) decreased proliferation, migration, invasion, and sphere formation in AD cell lines. Correspondingly, nestin upregulation by nestin gene transfection in these cells resulted in the opposite changes. Moreover, we performed screening analysis to clarify the upstream molecule that regulates nestin expression, using 95 chemical compounds that each inhibited a specific molecular target. Akt inhibitor IV led to a 72% reduction of nestin expression compared to in the DMSO-treated negative control in PC-3 cells. Akt is located downstream of the EGFR pathway, and Akt is reported to regulate SRY-box containing protein 2 (Sox2) expression and the self-renewal of CSC-like cells in NSCLC. Sox2 is also known to be a transcriptional factor for nestin. Immunohistochemically, we also confirmed co-expression of nestin, Akt, phosphorylated Akt, and Sox2 in serial tissue sections from AD cases. Thus, we performed further experiments using Akt inhibitor IV to clarify the relationship between Akt, Sox2, and nestin in AD cells. Akt inhibitor IV effectively decreased nestin expression via Sox2 downregulation and overcame the enhanced sphere formation induced by nestin upregulation. These findings suggest that nestin correlates to the aggressiveness and stemness of AD. Inhibition of nestin via Akt/Sox2 is thus a novel therapeutic approaches to eradicate lung AD and CSCs.

Citation Format: Kosuke Narita, Yoko Matsuda, Masahiro Seike, Zenya Naito, Akihiko Gemma, Toshiyuki Ishiwata. Nestin regulates proliferation, migration, invasion and stemness of lung adenocarcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4062. doi:10.1158/1538-7445.AM2014-4062

Abstract 784: Significance of osteopontin in the sensitivity of malignant pleural mesothelioma to pemetrexed

Background: Pemetrexed (PEM) is currently recommended as one of the standard anticancer drugs for malignant pleural mesothelioma (MPM). However, the mechanism of the sensitivity of MPM to PEM remains unclear.

Materials and Methods: We analyzed the antitumor effects of PEM in six MPM cell lines by MTS assay. To identify genes associated with drug sensitivity, we conducted gene expression profiling on the same set of cell lines using GeneChips and pathway analysis.

Results: Three cell lines were sensitive to PEM. Eighteen transcripts and fourteen genes identified by Gene-chips were significantly correlated with sensitivity to PEM. Pathway analysis revealed that osteopontin (SPP1/OPN) was an important target in PEM sensitivity. Overexpression of SPP1/OPN was observed in the sensitive cells by quantitative RT-PCR analysis and Western blotting. Introduction of SPP1/OPN by lentiviral vector significantly enhanced the invasion activities of MPM cells. PEM treatment with SPP1/OPN knockdown inhibited the PEM-induced cell growth-inhibitory effect in PEM-sensitive cells. Expression of SPP1/OPN and AKT phosphorylation significantly decreased after PEM treatment of the PEM sensitive cells. High immunohistochemical expression of SPP1/OPN was observed in two of three MPM patients who had a partial response to PEM-based chemotherapy.

Conclusion: PEM has anti-tumor effects in MPM cells dependent on SPP1/OPN overexpression resulting in AKT activation. Our results suggest that SPP1 may be used as a single predictive biomarker of the effectiveness of PEM treatment in MPM.

Citation Format: Susumu Takeuchi, Masahiro Seike, Rintaro Noro, Chie Soeno, Teppei Sugano, Fenfei Zou, Masaru Matsumoto, Akihiko Miyanaga, Yuji Minegishi, Kaoru Kubota, Akihiko Gemma. Significance of osteopontin in the sensitivity of malignant pleural mesothelioma to pemetrexed. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 784. doi:10.1158/1538-7445.AM2014-784

Senescence is involved in the pathogenesis of chronic obstructive pulmonary disease through effects on telomeres and the anti-aging molecule fibroblast growth factor 23

AIM

Fibroblast growth factor 23 knockout mice develop premature aging and emphysema, indicating that dysregulation of the normal aging process is involved in the pathobiology of chronic obstructive pulmonary disease. Thus, we explored the association among a coding single-nucleotide polymorphism of fibroblast growth factor 23, its protein concentration in serum and telomere length in patients with chronic obstructive pulmonary disease.

METHODS

The study involved 361 smokers; among whom, 244 were patients with chronic obstructive pulmonary disease. We genotyped a coding single-nucleotide polymorphism of fibroblast growth factor 23, rs7955866, and measured the telomere length of the peripheral blood cells. We also determined emphysema severity and airflow obstruction using computed tomography and pulmonary function tests, respectively. Furthermore, we analyzed the association between the disease phenotypes and fibroblast growth factor 23 genotypes or telomere length of peripheral blood leukocytes, as well as the association between the serum level of the studied protein and its genotypes.

RESULTS

The mice with A alleles on rs7955866 showed severe upper lung emphysema (P = 0.008). The serum concentration of the tested protein was lower in the mice with A allele than in the G homozygotes (P = 0.004). Telomere shortening was associated with airflow obstruction (P = 0.009), but not with upper lung emphysema.

CONCLUSIONS

A variation of fibroblast growth factor 23 with a reduced serum concentration appeared to promote emphysema formation. Telomere shortening in peripheral blood leukocytes was not associated with emphysema, but with airflow obstruction in chronic obstructive pulmonary disease through an independent mechanism.

MiR-379/411 cluster regulates IL-18 and contributes to drug resistance in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rapidly fatal malignancy that is increasing in incidence in Japan. In this study, we performed gene and microRNA (miRNA) expression profiling to identify novel therapeutic targets in MPM cells. Based on relative sensitivities to pemetrexed (PEM) and the histone deacetylase (HDAC) inhibitor, vorinostat (SAHA), 211H cells were determined to be the only sensitive MPM cell line out of the 6 tested. On the same series of cell lines, we performed whole genome transcriptomic profiling via DNA microarrays and pathway analysis of the derived data. Of particular note, IL-18 gene expression levels were significantly higher in the cell lines that were either drug resistant or displayed intermediate sensitivity, compared to the sensitive 211H cell line. Pathway analysis revealed IL-18 as an important gene associated with drug sensitivity of MPM cells. A relationship between IL-18 overexpression and drug resistance was also observed following targeted assessment of 10 cytokine genes using quantitative RT-PCR. miRNA expression profiles were evaluated in the MPM cell line panel in order to discern the mechanism of IL-18 induction in the drug-resistant lines. We found that miR-379 and miR-411 belonged to the same cluster of miRNAs located on chromosome 14q32 that commonly target the IL-18 gene. Luciferase reporter assays revealed that miR-379 and miR-411 directly target the IL-18 gene. Introduction of miR-379 plus miR-411, as well as IL-18 silencing, significantly suppressed the invasive capacity of MESO1 cells in vitro. Furthermore, the use of either PEM or SAHA together with miR-379 plus miR-411 mimics mediated increased sensitivity to these drugs in MESO1 cells. These results suggest that the miR-379/411 cluster may provide new therapeutic opportunities for advanced MPM patients, depending on the nature of IL-18 gene expression.

A phase II study of erlotinib monotherapy in pre-treated non-small cell lung cancer without EGFR gene mutation who have never/light smoking history: re-evaluation of EGFR gene status (NEJ006/TCOG0903)

OBJECTIVES

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors are particularly effective in non-small cell lung cancer (NSCLC) patients harboring active EGFR mutations. However, some studies have reported survival benefits in NSCLC patients with wild-type EGFR upon erlotinib treatment. This trial was conducted to evaluate the efficacy of erlotinib monotherapy and investigate the predictive values of several biomarkers.

PATIENTS AND METHODS

Patients with previously treated NSCLC but without EGFR gene mutations that had never or light smoked were eligible for this study. Gene status screening was performed using the PNA-LNA PCR clamp method. Erlotinib was administered until disease progression or unacceptable toxicities occurred. EGFR gene status was re-evaluated using the fragment method to detect exon 19 deletions and the Cycleave-PCR method to detect point mutations. Expression of hepatocyte growth factor (HGF), Met, and thymidylate synthase (TS) were evaluated using immunohistochemistry.

RESULTS

Forty-seven patients were enrolled in the study between March 2010 and November 2011. Objective response rate (ORR) and disease control rate (DCR) were 15.2% and 41.3%. Re-evaluations for EGFR gene were performed in 32 tumor samples. EGFR gene mutations were found in eight samples (5:exon 19 deletion, 2:G719X, 1:L858R). Six patients had PR and two had SD among these eight patients. A total of 24 patients were confirmed as wild-type EGFR using different methods. ORR and DCR were 4.2% and 41.7%. The median progression free survival (PFS) and median survival times were 2.0 and 6.0 months, respectively. Patients with tumors expressing HGF showed shorter PFS but not MET or TS.

CONCLUSIONS

Re-examination of EGFR gene status using different detecting method or different sample should be considered to grasp a chance of erlotinib treatment after first line treatment. In confirmed EGFR wild NSCLC, negative HGF staining could be a biomarker for longer PFS by erlotonib treatment.

Incidence and clinical features of drug-induced lung injury in patients with advanced colorectal cancer receiving cetuximab: results of a prospective multicenter registry

Objective

We investigated the incidence and clinical features of drug-induced lung injury during cetuximab therapy in Japanese patients with colorectal cancer in a prospective multicenter registry based on a central registration system.

Methods

We investigated and followed up patients with or suspected of having drug-induced lung injury among 2006 patients with cetuximab-treated colorectal cancer. A subcommittee of medical oncologists, pulmonologists and a radiologist evaluated and discussed each case of drug-induced lung injury that occurred during cetuximab therapy.

Results

Sixty-six patients were identified and further examinations of drug-induced lung injury were conducted during the registration period. We analyzed time to onset, patient characteristics and factors associated with mortality. Cetuximab-related drug-induced lung injury occurred in 24 (1.2%) patients, and was rated as Grade 3 or worse in 15 (0.7%) patients. Fourteen patients received steroid pulse therapy. Ten patients with drug-induced lung injury died, of whom eight received steroid pulse therapy. The incidence of drug-induced lung injury was significantly higher in elderly patients, and in patients with prior interstitial lung disease. There was no particular trend in the time to onset. Patients with early onset of drug-induced lung injury (within 90 days) after starting cetuximab therapy had higher mortality than patients with later onset (over 90 days).

Conclusions

The incidence of drug-induced lung injury in cetuximab-treated patients was 1.2%. Because drug-induced lung injury is potentially serious, it is important to promptly initiate appropriate treatments. Considering that early onset drug-induced lung injury during cetuximab therapy is associated with a poor prognosis, close monitoring is mandatory for these patients.

Association of serum interleukin-27 with the exacerbation of chronic obstructive pulmonary disease

We have previously demonstrated that chronic obstructive pulmonary disease (COPD) patients who do not have Siglec‐14 are less prone to exacerbation of the disease. Siglec‐14 is a myeloid cell protein that recognizes bacteria and triggers inflammatory responses. Therefore, soluble mediators secreted by myeloid cells responding to Siglec‐14 engagement could be involved in the pathogenesis of exacerbation and could potentially be utilized as biomarkers of exacerbation. To find out, we sought genes specifically induced in Siglec‐14⁺ myeloid cells and evaluated their utility as biomarkers of COPD exacerbation. Using DNA microarray, we compared gene expression levels in Siglec‐14⁺ and control myeloid cell lines stimulated with or without nontypeable Haemophilus influenzae to select genes that were specifically induced in Siglec‐14⁺ cells. The expressions of several cytokine and chemokine genes were specifically induced in Siglec‐14⁺ cells. The concentrations of seven gene products were analyzed by multiplex bead array assays in paired COPD patient sera (n = 39) collected during exacerbation and stable disease states. Those gene products that increased during exacerbation were further tested using an independent set (n = 32) of paired patient sera. Serum concentration of interleukin‐27 (IL‐27) was elevated during exacerbation (discovery set: P = 0.0472; verification set: P = 0.0428; combined: P = 0.0104; one‐sided Wilcoxon matched‐pairs signed‐rank test), particularly in exacerbations accompanied with sputum purulence and in exacerbations lasting more than a week. We concluded that IL‐27 might be mechanistically involved in the exacerbation of COPD and could potentially serve as a systemic biomarker of exacerbation.

e12069

Chronic obstructive pulmonary disease (COPD) patients who do not have Siglec‐14 (a myeloid cell protein that triggers inflammatory responses) are less prone to exacerbation of the disease. We tested whether soluble mediators secreted by myeloid cells responding to Siglec‐14 engagement could be utilized as biomarkers of exacerbation, and found serum concentration of interleukin‐27 (IL‐27) was elevated during exacerbation, particularly in exacerbations accompanied with sputum purulence. We concluded that IL‐27 might be mechanistically involved in the exacerbation of COPD and could potentially serve as a systemic biomarker of exacerbation.

An autopsy study of combined pulmonary fibrosis and emphysema: correlations among clinical, radiological, and pathological features

Background

Clinical evaluation to differentiate the characteristic features of pulmonary fibrosis and emphysema is often difficult in patients with combined pulmonary fibrosis and emphysema (CPFE), but diagnosis of pulmonary fibrosis is important for evaluating treatment options and the risk of acute exacerbation of interstitial pneumonia of such patients. As far as we know, it is the first report describing a correlation among clinical, radiological, and whole-lung pathological features in an autopsy cases of CPFE patients.

Methods

Experts retrospectively reviewed the clinical charts and examined chest computed tomography (CT) images and pathological findings of an autopsy series of 22 CPFE patients, and compared these with findings from 8 idiopathic pulmonary fibrosis (IPF) patients and 17 emphysema-alone patients.

Results

All patients had a history of heavy smoking. Forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC%) was significantly lower in the emphysema-alone group than the CPFE and IPF-alone groups. The percent predicted diffusing capacity of the lung for carbon monoxide (DLCO%) was significantly lower in the CPFE group than the IPF- and emphysema-alone groups. Usual interstitial pneumonia (UIP) pattern was observed radiologically in 15 (68.2%) CPFE and 8 (100%) IPF-alone patients and was pathologically observed in all patients from both groups. Pathologically thick-cystic lesions involving one or more acini with dense wall fibrosis and occasional fibroblastic foci surrounded by honeycombing and normal alveoli were confirmed by post-mortem observation as thick-walled cystic lesions (TWCLs). Emphysematous destruction and enlargement of membranous and respiratory bronchioles with fibrosis were observed in the TWCLs. The cystic lesions were always larger than the cysts of honeycombing. The prevalence of both radiological and pathological TWCLs was 72.7% among CPFE patients, but no such lesions were observed in patients with IPF or emphysema alone (p = 0.001). The extent of emphysema in CPFE patients with TWCLs was greater than that in patients without such lesions. Honeycombing with emphysema was also observed in 11 CPFE patients.

Conclusions

TWCLs were only observed in the CPFE patients. They were classified as lesions with coexistent fibrosing interstitial pneumonia and emphysema, and should be considered an important pathological and radiological feature of CPFE.

A descriptive analysis of post-chemotherapy development of interstitial lung disease using spontaneous reporting data in Japan

This descriptive study used the Japanese spontaneous reporting data to investigate the time taken (TTILD) to development of interstitial lung disease (ILD) after initiation of chemotherapy and the death rates attributed in part to post-chemotherapy ILD (i.e., DR) for anticancer drugs. We evaluated TTILD and DR endpoints for 36 anticancer drugs, which are widely used for treating 11 solid and 3 hematological cancers, and are suspected of causing ILD, by using 8- year spontaneous reporting data recording for 2,553 patients in the reporting system of the relevant Japanese regulatory agency. The median TTILD and overall DR attributable to post-chemotherapy ILD for the drugs were 1.8 months and 29%, respectively. For most drugs, the median TTILDs were between 1 to 4 months, and the DRs attributable to postchemotherapy ILD were <40%; however, TTILDs were as long as 4 to 6 months and DRs attributable to postchemotherapy ILD were ≥40% for several other drugs. Of the 36 drugs, we identified those that may trigger postchemotherapy late-onset ILDs or result in high DRs. The anticancer drugs that may have triggered late-onset ILDs were defined as those that caused ILD development after approximately 4 months from the initial drug administration.

Significance of osteopontin in the sensitivity of malignant pleural mesothelioma to pemetrexed

Pemetrexed (PEM) is currently recommended as one of the standard anticancer drugs for malignant pleural mesothelioma (MPM). However, the mechanism of the sensitivity of MPM to PEM remains unclear. We analyzed the antitumor effects of PEM in six MPM cell lines by MTS assay. To identify genes associated with drug sensitivity, we conducted gene expression profiling on the same set of cell lines using GeneChips and pathway analysis. Three cell lines were sensitive to PEM. A total fo 18 transcripts and 14 genes identified by GeneChips were significantly correlated with sensitivity to PEM. Pathway analysis revealed that osteopontin (SPP1/OPN) was an important target in PEM sensitivity. Overexpression of SPP1/OPN was observed in the sensitive cells by quantitative PCR and western blot analysis. Introduction of SPP1/OPN by lentiviral vector significantly enhanced the invasion activities of MPM cells. PEM treatment with SPP1/OPN knockdown inhibited the PEM-induced cell growth-inhibitory effect in PEM-sensitive cells. Expression of SPP1/OPN and AKT phosphorylation significantly decreased after PEM treatment of the PEM-sensitive cells. High immunohistochemical expression of SPP1/OPN was observed in two of three MPM patients who had a partial response to PEM-based chemotherapy. PEM has antitumor effects in MPM cells dependent on SPP1/OPN overexpression resulting in AKT activation. Our results suggest that SPP1 may be used as a single predictive biomarker of the effectiveness of PEM treatment in MPM.

Evaluation of right ventricular function in patients with COPD

BACKGROUND

Pulmonary hypertension is an independent risk factor for death in patients with COPD. Current prognostic models of COPD do not include sufficient indicators of right ventricular (RV) function to enable accurate assessment of changes in RV function over time. The aim of the present study was to test the hypothesis that it would be useful to include noninvasive markers of RV function in the routine assessment and prognostic models of early stage COPD with or without pulmonary hypertension.

METHODS

We reviewed the clinical records of 49 male subjects who had COPD but no other conditions that might affect physical status or prognosis, who underwent cardiac ultrasonography. Various echocardiographic parameters of pulmonary circulation and RV function were compared with indices of physical status and prognosis.

RESULTS

The Medical Research Council dyspnea score was higher in subjects with echocardiographic findings suggestive of pulmonary hypertension than those without (mean ± SD 3.17 ± 1.23 vs 2.26 ± 0.81, P = .02). RV ejection time, RV isovolumetric relaxation time, RV isovolumetric contraction time + RV isovolumetric relaxation time, and RV total ejection isovolume index differed significantly between subjects with echocardiographic findings suggestive of pulmonary hypertension and those without. The RV total ejection isovolume index was strongly correlated with the MRC score (P < .001), and was significantly correlated with the overall survival rate (hazard ratio 5.31, 95% CI 1.91-14.77) and hospital-free survival rate (hazard ratio 3.26, 95% CI 1.48-7.16).

CONCLUSIONS

It may be valuable to add assessment of RV function to the routine evaluation of physical status in patients with COPD.

Randomized phase II trial comparing carboplatin plus weekly paclitaxel and docetaxel alone in elderly patients with advanced non-small cell lung cancer: north japan lung cancer group trial 0801

BACKGROUND

Standard first-line chemotherapy for elderly non-small cell lung cancer (NSCLC) patients has been monotherapy with vinorelbine or gemcitabine. Docetaxel has also been considered as an alternative option for the elderly population in Japan. We have previously demonstrated the high efficacy of carboplatin plus weekly paclitaxel for elderly NSCLC patients. Consequently, we conducted a randomized phase II study to select the proper regimen for a future phase III trial.

METHODS

Eligible patients were aged 70 years or older with newly diagnosed advanced NSCLC. Patients were randomly assigned either to a combination of carboplatin (area under the curve: 6 mg/mL per minute) with weekly paclitaxel (70 mg/m²) (CP regimen) or to single-agent docetaxel (60 mg/m²). The primary endpoint of this study was objective response rate. Secondary endpoints were progression-free survival, overall survival, and toxicity profile.

RESULTS

Among 83 eligible patients (41 to CP, 42 to docetaxel), the objective response rates were 54% (95% confidence interval: 39%-69%) and 24% (95% confidence interval: 11%-37%) and median progression-free survival was 6.6 months and 3.5 months in the CP arm and the docetaxel arm, respectively. Severe neutropenia, febrile neutropenia, and nausea were significantly frequent in the docetaxel arm, whereas toxicities in the CP arm were generally moderate. One treatment-related death was observed in the docetaxel arm.

CONCLUSION

The CP regimen achieved higher activity with less toxicity than single-agent docetaxel. Considering the results of this phase II trial and the IFCT-0501 trial, we have selected the CP regimen for a future phase III trial in elderly patients with advanced NSCLC.

Panitumumab in Japanese patients with unresectable colorectal cancer: a post-marketing surveillance study of 3085 patients

Objective

Panitumumab was approved in Japan in April 2010 for the treatment of Kirsten rat sarcoma-2 virus oncogene wild-type unresectable and recurrent colorectal cancer. We conducted a post-marketing surveillance study to evaluate the safety and effectiveness of panitumumab.

Methods

After panitumumab was commercially available in Japan, all patients to be treated with panitumumab were enrolled. Data on baseline characteristics, treatment outcome, and incidence and severity of adverse drug reactions were collected.

Results

In total, 3091 patients were registered. In the safety analysis set (n = 3085), panitumumab was administered as monotherapy (40.7%) or combination therapy (59.4%). The median treatment duration was 113 days (range: 1–559 days), and 451 (14.6%) patients received panitumumab for ≥10 months. The overall incidence rate of adverse drug reactions was 84.1%, and the most common adverse drug reaction was skin disorders (78.4%). The incidence rates (all grades) of interstitial lung disease, infusion reaction, electrolyte abnormalities and cardiac disorders were 1.3% (mortality rate: 0.6%), 1.5, 19.3 and 0.2%, respectively. The median survival time of patients treated with panitumumab monotherapy as the third-line, or later, therapy was 10.3 months.

Conclusion

This post-marketing survey in clinical practice confirmed the safety and effectiveness of panitumumab. The benefit/risk balance for panitumumab in Japanese patients with unresectable colorectal cancer remains favorable.

Pirfenidone inhibits fibrocyte accumulation in the lungs in bleomycin-induced murine pulmonary fibrosis

BACKGROUND

Bone marrow-derived fibrocytes reportedly play important roles in the pathogenesis of idiopathic pulmonary fibrosis. Pirfenidone is an anti-fibrotic agent; however, its effects on fibrocytes have not been investigated. The aim of this study was to investigate whether pirfenidone inhibits fibrocyte pool size in the lungs of bleomycin-treated mice.

METHODS

Bleomycin (100 mg/kg) was infused with osmotic pumps into C57BL/6 mice, and pirfenidone (300 mg/kg/day) was orally administered daily for 2 wk. The lungs were removed, and single-cell suspensions were subjected to fluorescence-activated cell sorter (FACS) analysis to detect fibrocytes, which were defined as CD45 and collagen-I double-positive cells. Immunohistochemistry was performed on the lung specimens to quantify fibrocytes. Chemokines in the lung digests were measured with enzyme-linked immunosorbent assay. The effect of pirfenidone on alveolar macrophages was evaluated with bronchoalveolar lavage (BAL). In a therapeutic setting, pirfenidone administration was initiated 10 days after bleomycin treatment. For chemotaxis assay, lung fibrocytes were isolated with immunomagnetic selection (CD45-positive mesenchymal cells) after culture and allowed to migrate toward chemokines in the presence or absence of pirfenidone. Moreover, the effect of pirfenidone on the expression of chemokine receptors on fibrocytes was evaluated.

RESULTS

Pirfenidone significantly ameliorated bleomycin-induced pulmonary fibrosis as assessed with quantitative histology and collagen measurement. Fibrocyte pool size in bleomycin-treated mice lungs was attenuated from 26.5% to 13.7% by pirfenidone on FACS analysis. This outcome was also observed in a therapeutic setting. Immunohistochemistry revealed that fibrocytes were significantly decreased by pirfenidone administration compared with those in bleomycin-treated mice (P = 0.0097). Increased chemokine (CC motif) ligand-2 (CCL2) and CCL12 production in bleomycin-treated mouse lungs was significantly attenuated by pirfenidone (P = 0.0003 and P < 0.0001, respectively). Pirfenidone also attenuated macrophage counts stimulated by bleomycin in BAL fluid. Fibrocyte migration toward CCL2 and chemokine (CC motif) receptor-2 expression on fibrocytes was significantly inhibited by pirfenidone in vitro.

CONCLUSIONS

Pirfenidone attenuated the fibrocyte pool size in bleomycin-treated mouse lungs via attenuation of CCL2 and CCL12 production in vivo, and fibrocyte migration was inhibited by pirfenidone in vitro. Fibrocyte inhibition is considered a mechanism of anti-fibrotic action of pirfenidone.

Bortezomib therapy-related lung disease in Japanese patients with multiple myeloma: incidence, mortality and clinical characterization

Because of the potentially high mortality rate (6.5%) associated with bortezomib-induced lung disease (BILD) in Japanese patients with relapsed or refractory multiple myeloma, we evaluated the incidence, mortality and clinical features of BILD in a Japanese population. This study was conducted under the Risk Minimization Action Plan (RMAP), which was collaboratively developed by the pharmaceutical industry and public health authority. The RMAP consisted of an intensive dissemination of risk information and a recommended countermeasure to health-care professionals. All patients treated with bortezomib were consecutively registered in the study within 1 year and monitored for emerging BILD. Of the 1010 patients registered, 45 (4.5%) developed BILD, 5 (0.50%) of whom had fatal cases. The median time to BILD onset from the first bortezomib dose was 14.5 days, and most of the patients responded well to corticosteroid therapy. A retrospective review by the Lung Injury Medical Expert Panel revealed that the types with capillary leak syndrome and hypoxia without infiltrative shadows were uniquely and frequently observed in patients with BILD compared with those with conditions associated with other molecular-targeted anticancer drugs. The incidence rate of BILD in Japan remains high compared with that reported in other countries, but the incidence and mortality rates are lower than expected before the introduction of bortezomib in Japan. This study describes the radiographic pattern and clinical characterization of BILD in the Japanese population. The RMAP seemed clinically effective in minimizing the BILD risk among our Japanese population.