Takeru Kashiwada

β-Catenin-dependent transcription is central to Bmp-mediated formation of venous vessels.

β-catenin regulates the transcription of genes involved in diverse biological processes, including embryogenesis, tissue homeostasis and regeneration. Endothelial cell (EC)-specific gene-targeting analyses in mice have revealed that β-catenin is required for vascular development. However, the precise function of β-catenin-mediated gene regulation in vascular development is not well understood, since β-catenin regulates not only gene expression but also the formation of cell-cell junctions. To address this question, we have developed a novel transgenic zebrafish line that allows the visualization of β-catenin transcriptional activity specifically in ECs and discovered that β-catenin-dependent transcription is central to the bone morphogenetic protein (Bmp)-mediated formation of venous vessels. During caudal vein (CV) formation, Bmp induces the expression of aggf1, a putative causative gene for Klippel–Trenaunay syndrome, which is characterized by venous malformation and hypertrophy of bones and soft tissues. Subsequently, Aggf1 potentiates β-catenin transcriptional activity by acting as a transcriptional co-factor, suggesting that Bmp evokes β-catenin-mediated gene expression through Aggf1 expression. Bmp-mediated activation of β-catenin induces the expression of Nr2f2 (also known as Coup-TFII), a member of the nuclear receptor superfamily, to promote the differentiation of venous ECs, thereby contributing to CV formation. Furthermore, β-catenin stimulated by Bmp promotes the survival of venous ECs, but not that of arterial ECs. Collectively, these results indicate that Bmp-induced activation of β-catenin through Aggf1 regulates CV development by promoting the Nr2f2-dependent differentiation of venous ECs and their survival. This study demonstrates, for the first time, a crucial role of β-catenin-mediated gene expression in the development of venous vessels. Highlighted article: In the developing fish caudal vein, β-catenin is activated by BMP in a Wnt-independent manner and cooperates with Aggf1 to control venous endothelial cell differentiation.

Hypercytokinemia with 2009 pandemic H1N1 (pH1N1) influenza successfully treated with polymyxin B-immobilized fiber column hemoperfusion

In September 2009, a 16-year-old female with no medical history developed fever, general fatigue, and diarrhea. A rapid diagnosis kit at a local clinic showed type A influenza. She was given 10 mg zanamivir inhalation, twice daily. The following day, her body temperature rose to 41.7 C and she experienced respiratory distress. She was transported to our hospital by ambulance. On arrival, her blood pressure was 90/ 40 mmHg, heart rate 150/min, and respiratory rate 35/min. She was administered a large dose of crystalloid fluid and norepinephrine (0.3 lg/kg/min). Mechanical ventilation with endotracheal intubation was begun. Purulent sputum removed by suction contained Gram-positive cocci on a Gram-stained smear. Cultures of blood, urine, and stool testing for various pathogens were negative. Mechanical ventilation was performed in pressure control mode with PaO2/FiO2 (P/F) ratio of 148. Thereafter, a recruitment maneuver was performed, switching to airway pressure release ventilation (APRV) mode. P/F ratio temporarily improved to 224, but then deteriorated to 165. Oseltamivir (150 mg/day), sivelestat sodium hydrate (300 mg/day), and antibiotics (initially ampicillin/ sulbactam 6 g/day) were administered. On day 2, complicated by disseminated intravascular coagulation, no improvement in respiratory status was observed, prompting an increase in oseltamivir dosage to 300 mg/day. Type A influenza was confirmed as 2009 pandemic H1N1 (pH1N1) virus by polymerase chain reaction (PCR). On day 3, methicillin-resistant Staphylococcus aureus (MRSA) was identified in the sputum collected immediately after intubation. Antibiotics were changed to linezolid (12 g/day) plus clindamycin (1,800 mg/day) for MRSA. Serum cytokine levels were highly elevated (Fig. 1). We considered that the severe respiratory failure might be related to hypercytokinemia caused by pH1N1 and MRSA infection. With no improvement in oxygenation, polymyxin B-immobilized fiber column (PMX) hemoperfusion was begun in an attempt to reduce the inflammatory mediators and improve oxygenation. Oxygenation gradually improved; after 1 h, the P/F ratio increased from 144 to 184, and after 8 h to 308. PMX hemoperfusion was performed for 14 h; following cessation, oxygenation declined (P/F ratio 220). On days 4 and 5, PMX hemoperfusion was planned for 18 h on each day, and the P/F ratio increased to 407. Serum inflammatory mediators decreased to normal levels after the PMX treatments. She was extubated and discharged from the hospital. Respiratory failure accounts for a large proportion of pH1N1-related deaths. In influenza A (H5N1) virus infection, hypercytokinemia was observed in fatal cases [1]. We postulated that hypercytokinemia led to respiratory failure. A fatal case of

The parallel growth of motoneuron axons with the dorsal aorta depends on Vegfc/Vegfr3 signaling in zebrafish.

Blood vessels and neurons grow often side by side. However, the molecular and cellular mechanisms underlying their parallel development remain unclear. Here, we report that a subpopulation of secondary motoneurons extends axons ventrally outside of the neural tubes and rostrocaudally as a fascicle beneath the dorsal aorta (DA) in zebrafish. We tried to clarify the mechanism by which these motoneuron axons grow beneath the DA and found that Vegfc in the DA and Vegfr3 in the motoneurons were essential for the axon growth. Forced expression of either Vegfc in arteries or Vegfr3 in motoneurons resulted in enhanced axon growth of motoneurons over the DA. Both vegfr3 morphants and vegfc morphants lost the alignment of motoneuron axons with DA. In addition, forced expression of two mutant forms of Vegfr3 in motoneurons, potentially trapping endogenous Vegfc, resulted in failure of growth of motoneuron axons beneath the DA. Finally, a vegfr3 mutant fish lacked the motoneuron axons beneath the DA. Collectively, Vegfc from the preformed DA guides the axon growth of secondary motoneurons.

Pulmonary embolism and deep vein thrombosis in eosinophilic granulomatosis with polyangiitis successfully treated with rivaroxaban

A 41-year-old woman presented complaining of cough and purpura for one month. On her first visit, a blood test demonstrated peripheral blood eosinophilia, but chest radiography showed no abnormalities. However, 2 days after the first visit, she went to the emergency room because of fever and right-sided chest pain. Contrast-enhanced computed tomography of the chest showed pulmonary embolism and air space consolidation. Thrombosis was present in the popliteal vein. Bronchoscopy revealed alveolar hemorrhage and increased eosinophils in the bronchoalveolar lavage fluid, and a skin biopsy demonstrated a perivascular eosinophilic infiltrate. The patient was diagnosed with eosinophilic granulomatosis with polyangiitis (EGPA). We started steroid therapy and low-molecular-weight heparin (LMWH). The chest pain and fever disappeared, and the peripheral eosinophil count normalized. However, the thrombosis in the leg worsened. It was dramatically improved by changing from LMWH to oral rivaroxaban. The thrombogenic risk of eosinophilia should be recognized. This case suggests that oral rivaroxaban is useful when thrombosis is uncontrolled by LMWH in a patient with EGPA.

Pembrolizumab-induced agranulocytosis in a pulmonary pleomorphic carcinoma patient who developed interstitial lung disease and ocular myasthenia gravis

Abstract An 82-year-old man with a recurrence of pulmonary pleomorphic carcinoma was treated with pembrolizumab. He achieved partial response after three cycles of pembrolizumab. However, he developed febrile neutropenia. A bone marrow aspiration sample revealed a decrease of mature neutrophils, and anti-neutrophil antibody was detected in blood. Computed tomography scans revealed consolidation in the right lung. Pathological findings in lung biopsy tissue revealed organizing pneumonia. Pembrolizumab-induced agranulocytosis and interstitial lung disease (ILD) were diagnosed. We initiated antibacterial therapy and granulocyte colony-stimulating factor (G-CSF). The neutrophil count immediately increased, and the fever decreased. The improvement of ILD was achieved without using systemic steroids. Moreover, the patient developed ocular myasthenia gravis induced by pembrolizumab. This is the first case report of pembrolizumab-induced agranulocytosis. Agranulocytosis was improved by administration of G-CSF without using systemic steroids. However, further studies are needed to determine the optimal treatment for patients with anti-neutrophil antibody whose tumor has progressed.

A case of interstitial lung disease with alveolar hemorrhage induced by pembrolizumab

We herein describe the case of a 67-year-old woman with advanced lung adenocarcinoma who developed interstitial lung disease (ILD) with alveolar hemorrhage induced by pembrolizumab. She received four courses of pembrolizumab therapy and achieved a partial response. She had no respiratory symptoms; however, chest radiography and computed tomography (CT) revealed ground-glass opacities (GGOs) and crazy-paving pattern. Based on findings of bloody bronchoalveolar lavage fluid and transbronchial lung biopsy samples, pembrolizumab-induced ILD with alveolar hemorrhage was diagnosed. Corticosteroid therapy rapidly improved alveolar hemorrhage and regressed GGOs on CT scan. This is the first report on ILD with alveolar hemorrhage induced by pembrolizumab.

Pembrolizumab and salvage chemotherapy in EGFR T790M-positive non-small-cell lung cancer with high PD-L1 expression

Immuno-checkpoint inhibitors (ICI) have become an effective treatment option for non-small-cell lung cancer patients. However, ICI therapy was reported to be less effective in patients with epidermal growth factor receptor (EGFR) mutations than in those with wild-type EGFR. We report here that an non-small-cell lung cancer patient with the EGFR mutant T790M showed a programmed cell death ligand 1 (PD-L1) expression level that increased from <25% to >90% after eighth-line osimertinib therapy. He was treated with pembrolizumab as a ninth-line treatment, and attained stable disease. After the pembrolizumab therapy, he was treated with gemcitabine, which produced a good response despite being the 10th-line treatment. We should consider administering ICI and chemotherapy even to EGFR mutant patients after failure of EGFR tyrosine kinase inhibitor, especially in cases with high PD-LI expression.

Prognostic Factors in the Acute Exacerbation of Idiopathic Pulmonary Fibrosis: A Retrospective Single-center Study

Objectives Acute exacerbation of idiopathic pulmonary fibrosis (IPF-AE) has been recognized as a fatal pulmonary disorder, but the exact prognostic factors are unknown. The aim of the present study was to analyze the clinical characteristics of patients with IPF-AE and identify the prognostic factors. Methods The medical records of 59 cases of IPF-AE were retrospectively reviewed. Clinical data, laboratory data, radiographic findings, treatment, and time from the onset of symptoms to the initiation of corticosteroid pulse therapy, i.e. symptom duration, and outcome were analyzed. Results The IPF Stage, Gender-Age-Physiology (GAP) Index, symptom duration, and the high-resolution computed tomography (HRCT) score were significantly related to the prognosis in the univariate analysis. In the multivariate analysis, the symptom duration remained a significant prognostic factor (hazard ratio of 1-day increase, 1.11; 95% confidence interval, 1.01-1.15; p=0.0427). The area under the receiver operating characteristics curve of symptom duration was statistically significant for survivors versus non-survivors (area under the curve, 0.73; p=0.012). The survival period was significantly shorter in the late-treatment groups (≥5 days; n=30) than in the early-treatment groups (<5 days; n=29; log-rank test; p<0.0001). Conclusion The time interval between the onset of symptoms and the initiation of corticosteroid pulse therapy may be an independent prognostic factor in patients with IPF-AE.

Granuloma-forming interstitial pneumonia induced by nivolumab: a possible immune-related adverse event of the lung

Nivolumab, a monoclonal antibody targeting the PD-1, has recently been used as a standard treatment for lung cancer, melanoma and renal cell carcinoma. We herein report the case of a patient undergoing treatment for non-small cell lung cancer (NSCLC) who developed interstitial pneumonia which featured nivolumab-induced granuloma formation. An 82-year-old male patient with NSCLC was initially treated with radiation therapy and chemotherapy. Five years later, however, he developed metastatic carcinoma in a hilar lymph node accompanied by ground glass opacity (GGO), suggesting tumor cell invasion. Treatment with nivolumab was initiated. At 21 days after the first dose of nivolumab, he complained of cough and dyspnea. Chest computed tomography scans demonstrated tumor progression and newly formed GGO in the area surrounding the primary tumor. Fibrosing active alveolitis with granuloma formation and organizing pneumonia findings were observed in the pathological examination of a transbronchial lung biopsy (TBLB) specimen. No malignant cells were found in TBLB. A bacteriological analysis of cultures, a PCR, and special staining did not reveal any infections. The patient’s pneumonitis improved after treatment with systemic corticosteroids. Granuloma-forming interstitial pneumonia may be a feature of nivolumab-associated pneumonitis.