Yuko Toyoda

Bestatin, an inhibitor for aminopeptidases, modulates the production of cytokines and chemokines by activated monocytes and macrophages

The aim of this study was to clarify the effect of bestatin, an aminopeptidase inhibitor, on the production of cytokines from peripheral blood monocytes and alveolar macrophages (AM). Human monocytes isolated from peripheral blood of healthy volunteers were incubated with or without lipopolysaccharide (LPS) in the presence or absence of bestatin. AM obtained from patients with sarcoidosis were incubated in the presence or absence of bestatin. The concentration of cytokines in the culture supernatant was determined by enzyme-linked immunosorbent assay. The expression of mRNA was determined by reverse transcription polymerase chain reaction. Bestatin suppressed the production and expression of proinflammatory cytokines and chemokines, interleukin (IL)-6, CXCL8/IL-8, CCL3/macrophage inflammatory protein (MIP)-1alpha by LPS-stimulated monocytes. The mean percentage of the inhibition of IL-6, CXCL8/IL-8, CCL3/MIP-1alpha by bestatin at a concentration of 50 microg/mL was 71.2%, 29.7% and 61.0%, respectively. On the other hand, bestatin increased the production and mRNA expression of IL-10 by LPS-stimulated monocytes. The treatment with bestatin significantly inhibited the production of IL-6 and CXCL8/IL-8 by AM from patients with sarcoidosis. The data presented here indicate that bestatin suppresses the production of the pro-inflammatory cytokines and stimulates the anti-inflammatory cytokine by activated human monocytes. This study suggests that bestatin may be useful as an anti-inflammatory agent in various inflammatory diseases.

Thymidine Phosphorylase Regulates the Expression of CXCL10 in Rheumatoid Arthritis Fibroblast‐like Synoviocytes

Thymidine phosphorylase (TP) in rheumatoid arthritis (RA) fibroblast‐like synoviocytes (FLS) is induced by tumor necrosis factor α (TNFα) and other cytokines that have been reported to be major inflammation mediators in RA. We previously demonstrated that TP plays an important role in angiogenesis and tumor growth, invasion, and metastasis. The aim of this study was to investigate whether the role of TP in the pathogenesis of RA is similar to its role in tumors.

Clinical features and outcome of acute exacerbation of interstitial pneumonia associated with connective tissue disease.

Acute exacerbation (AE) of interstitial lung disease is reported to be developed in not only idiopathic pulmonary fibrosis but also connective tissue disease-associated interstitial pneumonia (CTD-IP). As the significance of AE of CTD-IP has not been so widely recognized, its clinical feature is not fully elucidated. In the present study, we investigated the incidence, clinical features and outcome of AE of CTD-IP. We retrospectively reviewed admitted cases in our department with medical record from 2011 to 2015. Among 155 patients with CTD-IP, 10 (6.5%) cases developed AE (6 rheumatoid arthritis, 2 polymyositis/dermatomyositis, 1 systemic lupus erythematosus, 1 Sjögren syndrome), and one died of AE within 30 days. Median survival time after the onset of AE was 169 days in all 10 patients. The treatment with immunosuppressant just before AE onset might improve the prognosis of AE. The median survival time after the onset of AE was significantly longer in patients showing good response to corticosteroid compared with those with poor response to corticosteroid (805 days and 45 days, respectively) (p <0.05), suggesting that there are some cases in CTD-IP, showing the good response to corticosteroid even when AE was complicated. J. Med. Invest. 63: 294-299, August, 2016.

Anti-fibrotic efficacy of nintedanib in pulmonary fibrosis via the inhibition of fibrocyte activity

BackgroundNintedanib, a tyrosine kinase inhibitor that is specific for platelet-derived growth factor receptors (PDGFR), fibroblast growth factor receptors (FGFR), and vascular endothelial growth factor receptors (VEGFR), has recently been approved for idiopathic pulmonary fibrosis. Fibrocytes are bone marrow-derived progenitor cells that produce growth factors and contribute to fibrogenesis in the lungs. However, the effects of nintedanib on the functions of fibrocytes remain unclear.MethodsHuman monocytes were isolated from the peripheral blood of healthy volunteers. The expression of growth factors and their receptors in fibrocytes was analyzed using ELISA and Western blotting. The effects of nintedanib on the ability of fibrocytes to stimulate lung fibroblasts were examined in terms of their proliferation. The direct effects of nintedanib on the differentiation and migration of fibrocytes were also assessed. We investigated whether nintedanib affected the accumulation of fibrocytes in mouse lungs treated with bleomycin.ResultsHuman fibrocytes produced PDGF, FGF2, and VEGF-A. Nintedanib and specific inhibitors for each growth factor receptor significantly inhibited the proliferation of lung fibroblasts stimulated by the supernatant of fibrocytes. Nintedanib inhibited the migration and differentiation of fibrocytes induced by growth factors in vitro. The number of fibrocytes in the bleomycin-induced lung fibrosis model was reduced by the administration of nintedanib, and this was associated with anti-fibrotic effects.ConclusionsThese results support the role of fibrocytes as producers of and responders to growth factors, and suggest that the anti-fibrotic effects of nintedanib are at least partly mediated by suppression of fibrocyte function.

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.

A Patient with Idiopathic Pleuroparenchymal Fibroelastosis Showing a Sustained Pulmonary Function due to Treatment with Pirfenidone.

The patient was a 68-year-old man presenting with body weight loss and exertional dyspnea. High-resolution computed tomography of the chest showed dense subpleural consolidation with traction bronchiectasis and volume loss predominantly in bilateral apical lesions and upper lobes. A histopathological analysis of a specimen of the right upper lobe showed histological patterns which were consistent with idiopathic pleuroparenchymal fibroelastotis (IPPFE). Treatment with pirfenidone was introduced with the expectation of its potential benefit. The effect of pirfenidone was satisfactory, and a decline in forced vital capacity was inhibited during treatment. This is the first case report suggesting the efficacy of pirfenidone for patients with IPPFE.

An analysis of the clinical features of lung cancer in patients with connective tissue diseases

BACKGROUND Patients with connective tissue diseases (CTDs) are at increased risk for lung cancer (LC); interstitial lung disease (ILD) is a common form of organ dysfunction in cases of CTD. However, the influence of ILD on the treatment and prognosis in LC patients with CTD is unclear. METHODS Between January 2010 and December 2014, 27 patients among all patients with CTD at our institution were diagnosed with primary LC. We retrospectively analyzed the clinical features, treatment modalities, and outcomes of these patients, and evaluated the potential prognostic factors. Forty-four LC patients without CTD were also analyzed as a control cohort. RESULTS LC patients with CTD had a significantly higher incidence of ILD as a complication compared with those without CTD (52% and 14%, respectively). CTD-associated ILD (CTD-ILD) at diagnosis was associated with significantly worse survival in LC patients with CTD. Multivariate analysis demonstrated that the complication of CTD-ILD was an independent poor prognostic factor in LC patients with CTD. The incidence of acute exacerbation (AE) of CTD-ILD was 21% among LC patients with CTD, and all of these patients died despite intensive treatment including high-dose corticosteroids. The restrictions in curative therapy for LC due to the presence of ILD and AE of CTD-ILD were thought to be the major reasons for the poor outcome. CONCLUSIONS LC patients with CTD had a high prevalence of ILD, and the presence of CTD-ILD was significantly associated with poor prognosis.

A case of interstitial pneumonia associated with anti‐PL‐7 antibody in a patient with rheumatoid arthritis

A 65-year-old female had been treated rheumatoid arthritis (RA), interstitial pneumonia (IP) and nephrotic syndrome with prednisolone and cyclosporine. She was emergently admitted to our hospital due to the worsening exertional dyspnea and severe hypoxemia. Chest computed tomography (CT) showed new diffuse ground-glass opacities (GGOs) with slight consolidations along with bronchovascular bundle were observed in addition to pre-existing reticular shadows in both lungs with lower lobe-predominance. An acute exacerbation (AE) of pre-existing IP triggered by an infection was suspected, and the treatment with antibiotics and corticosteroid pulse therapy improved her general condition and chest radiological findings. Because some auto-antibodies associated with acute/subacute onset IP have recently become available in clinic, we examined those including anti-aminoacyl tRNA synthetase (ARS) antibodies, and found that she was positive for anti-PL-7 antibody. We diagnosed her anti-synthetase syndrome (ASS) without symptom of myositis, and her IP was considered to be ASS-related. The careful consideration is necessary to precisely diagnose and treat the patients with RA-associated interstitial lung diseases as the several etiologies may be overlapped in the same patient. J. Med. Invest. 65:147-150, February, 2018.

Thymidine catabolism promotes NADPH oxidase-derived reactive oxygen species (ROS) signalling in KB and yumoto cells

Thymidine phosphorylase (TP) is a rate-limiting enzyme in the thymidine catabolic pathway. TP is identical to platelet-derived endothelial cell growth factor and contributes to tumour angiogenesis. TP induces the generation of reactive oxygen species (ROS) and enhances the expression of oxidative stress-responsive genes, such as interleukin (IL)-8. However, the mechanism underlying ROS induction by TP remains unclear. In the present study, we demonstrated that TP promotes NADPH oxidase-derived ROS signalling in cancer cells. NADPH oxidase inhibition using apocynin or small interfering RNAs (siRNAs) abrogated the induction of IL-8 and ROS in TP-expressing cancer cells. Meanwhile, thymidine catabolism induced by TP increased the levels of NADPH and intermediates of the pentose phosphate pathway (PPP). Both siRNA knockdown of glucose 6-phosphate dehydrogenase (G6PD), a rate-limiting enzyme in PPP, and a G6PD inhibitor, dihydroepiandrosterone, reduced TP-induced ROS production. siRNA downregulation of 2-deoxy-D-ribose 5-phosphate (DR5P) aldolase, which is needed for DR5P to enter glycolysis, also suppressed the induction of NADPH and IL-8 in TP-expressing cells. These results suggested that TP-mediated thymidine catabolism increases the intracellular NADPH level via the PPP, which enhances the production of ROS by NADPH oxidase and activates its downstream signalling.

A case of pulmonary pleomorphic carcinoma with malignant phenotypes induced by ZEB1-associated epithelial-mesenchymal transition

A 60-year-old man was admitted to our hospital with non-small cell lung cancer (NSCLC). Imaging and pathological studies revealed NSCLC, not otherwise specified (NOS), at clinical stage T3N1M0 stage IIIA. We started radiotherapy alone because of obstructive pneumonia and end-stage renal disease, but the tumors progressed rapidly and resulted in death due to air obstruction by pharyngeal metastasis. The cancer was diagnosed as pleomorphic carcinoma in an autopsy. Viable lung tumor cells, which were resistant to radiotherapy, and the pharyngeal metastasis had mesenchymal phenotypes and expressed ZEB1 but not SNAI1. These observations indicated that ZEB1-associated epithelial-mesenchymal transition has malignant features including resistance to radiotherapy and aggressive metastatic potential. ZEB1-associated EMT may be an important mechanism to understand the pathophysiology of pleomorphic carcinoma.