Kosuke Mizoguchi

CRTH2 Is A Critical Regulator of Neutrophil Migration and Resistance to Polymicrobial Sepsis

Although arachidonic acid cascade has been shown to be involved in sepsis, little is known about the role of PGD2 and its newly found receptor, chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2), on the septic response. Severe sepsis is associated with the failure of neutrophil migration. To investigate whether CRTH2 influences neutrophil recruitment and the lethality during sepsis, sepsis was induced by cecal ligation and puncture (CLP) surgery in mice. CRTH2 knockout (CRTH2−/−) mice were highly resistant to CLP-induced sepsis, which was associated with lower bacterial load and lower production of TNF-α, IL-6, and CCL3. IL-10, an anti-inflammatory cytokine, was higher in CRTH2−/− mice, blunting CLP-induced lethality in CRTH2−/− mice. Neutrophil accumulation in the peritoneum was more pronounced after CLP in CRTH2−/− mice, which was associated with higher CXCR2 levels in circulating neutrophils. Furthermore, sepsis caused a decrease in the level of acetylation of histone H3, an activation mark, at the CXCR2 promoter in wild-type neutrophils, suggesting that CXCR2 expression levels are epigenetically regulated. Finally, both pharmacological depletion of neutrophils and inhibition of CXCR2 abrogated the survival benefit in CRTH2−/− mice. These results demonstrate that genetic ablation of CRTH2 improved impaired neutrophil migration and survival during severe sepsis, which was mechanistically associated with epigenetic-mediated CXCR2 expression. Thus, CRTH2 is a potential therapeutic target for polymicrobial sepsis.

Cytokine profile of bronchoalveolar lavage fluid in patients with combined pulmonary fibrosis and emphysema

Background and objective:  Combined pulmonary fibrosis and emphysema (CPFE) is characterized by upper lobe emphysema together with lower lobe fibrosis. The aim of this study was to examine whether cytokine levels in the alveolar space are associated with emphysematous changes superimposed on pulmonary fibrosis.

Cytokine profiles of bronchoalveolar lavage fluid in patients with pneumocystis pneumonia

The clinical features of PCP differ according to the factors responsible for the predisposing immunosuppression. Although the diagnosis of PCP often requires BAL, the profiles of the inflammatory mediators in the BAL fluid are not thoroughly documented. The aim of the current study was to characterize the profiles of inflammatory mediators in BAL fluid during PCP in patients with underlying autoimmune diseases, malignancies, or AIDS. The medical records of 14 patients with autoimmune diseases, 10 with malignancies, and 8 with AIDS, all of whom had been diagnosed with PCP by microscopic examination of BAL fluid, were reviewed. The concentrations of TNF‐α, MCP‐1, HMGB1, IL‐8, IL‐6, IL‐10, and IFN‐γ in the BAL fluid that had been obtained for the diagnosis of PCP were measured. The concentrations of MCP‐1, IL‐8, and IL‐6 differed according to the underlying disease, tending to be higher in patients with autoimmune diseases and lower in those with AIDS. The concentrations of HMGB1, IL‐8, and IL‐6 were positively correlated with the proportion of neutrophils in BAL fluid and inversely with the oxygenation index. Although the serum concentrations of CRP and LDH were positively correlated with those of IL‐8 and MCP‐1, none of the mediators in BAL fluid was correlated with the serum β‐D‐glucan concentration. The production of inflammatory mediators in the lung differed between the patient groups with different underlying disorders. The modest upregulation of IL‐8 and IL‐6 might be associated with the milder clinical manifestations of PCP in AIDS patients.

Analysis of intratumor heterogeneity of EGFR mutations in mixed type lung adenocarcinoma.

BACKGROUND Epidermal growth factor receptor mutations are predictive of the success of EGFR tyrosine kinase inhibitor treatment in patients with advanced non--small-cell lung cancer. As with other solid tumors, lung cancer is thought to be the result of an accumulation of genetic alterations after exposure to carcinogens. The aim of the present study was to clarify the relationship between multistep carcinogenesis and the accumulation of EGFR mutations. PATIENTS AND METHODS The intratumor heterogeneity of EGFR mutations was analyzed in 38 patients with resected mixed-type lung adenocarcinoma according to histological patterns, and the clinical features of the patients harboring intratumor heterogeneity of EGFR mutations were evaluated. RESULTS Intratumor heterogeneity of EGFR mutations was detected in 9 of 38 tumors. EGFR mutations were more common in the bronchioloalveolar (lepidic) carcinoma pattern than in the papillary and acinar patterns, although this difference was not significant. However, there was a significant correlation between intratumor heterogeneity of EGFR mutations and smoking history (P < .043). CONCLUSION Intratumor heterogeneity of EGFR mutations correlates with the distribution of histological subtype in mixed type adenocarcinoma and is associated with smoking history.

Direct comparison of 3 PCR methods in detecting EGFR mutations in patients with advanced non-small-cell lung cancer

BACKGROUND Epidermal growth factor receptor (EGFR) mutations are predictive of response to EGFR tyrosine kinase inhibitors (TKIs) in NSCLC. Several methods have been used to detect EGFR mutations; however, it is not clear which is the most suitable for use in the clinic. In this study, we directly compare the clinical sensitivity and specificity of 3 PCR methods. PATIENTS AND METHODS We compared the 3 PCR methods (mutant-enriched PCR, PNA-LNA PCR, and PCR clamp) in patients with advanced NSCLC. A patient who showed sensitive mutations by at least 1 PCR method was treated with gefitinib. A patient who showed no sensitive mutations was treated with chemotherapy with cytotoxic agents. RESULTS Fifty patients with advanced NSCLC previously untreated with EGFR-TKIs were enrolled in this trial. Seventeen patients were harboring EGFR mutations, 5 of whom showed discrepancies between the results of different PCR methods. All 5 patients responded to gefitinib. All patients harboring EGFR mutations received gefitinib treatment and 21 of 33 EGFR-mutation-negative patients received chemotherapy with cytotoxic agents. Median progression-free survival of the gefitinib group and the chemotherapy group were 8.2 and 5.9 months, respectively. CONCLUSION We considered that all the discrepancies might be false negatives because the patients responded to gefitinib. To clarify the reason for the false negatives of each PCR method, and establish the clinical sensitivity and specificity of each PCR method, a large prospective clinical trial is warranted.

Histone Deacetylase Inhibition Protects Mice Against Lethal Postinfluenza Pneumococcal Infection

Objectives:Secondary bacterial pneumonia following influenza virus infection is associated with high mortality, but the mechanism is largely unknown. Epigenetic gene regulation appears to play key roles in innate and adaptive immunity. We hypothesized that histone acetylation, a major epigenetic mechanism associated with transcriptionally active chromatin, might contribute to the poor outcome of postinfluenza pneumonia. Design:Prospective experimental study. Setting:University research laboratory. Subjects:C57BL/6 male mice. Interventions:Mice were infected intranasally with 1.0 × 104 colony-forming units of Streptococcus pneumoniae, 7 days after intranasal inoculation with five plaque-forming units of influenza virus A/H1N1/PR8/34. The mice were intraperitoneally injected with the histone deacetylase inhibitor trichostatin A (1 mg/kg) or vehicle once a day from 1 hour after pneumococcal infection throughout the course of the experiment. The primary outcome was survival rate. Measurements and Main Results:Trichostatin A significantly suppressed histone deacetylase activity and significantly improved the survival rate of mice (56.3%) after postinfluenza pneumococcal infection when compared with vehicle-treated mice (20.0%), which was associated with a significant decrease in the total cell count of the bronchoalveolar lavage fluid. The interleukin-1&bgr; level in the serum and the number of natural killer cells in the lungs were significantly lower in the trichostatin A-treated group. Conclusions:The histone deacetylase inhibitor trichostatin A protects mice against postinfluenza pneumonia possibly through multiple factors, including decreasing local cell recruitment into the lungs and suppressing systemic inflammation.

Secondary EML4–ALK-positive Lung Adenocarcinoma in a Patient Previously Treated for Acute Lymphoblastic Leukemia in Childhood: A Case Report

It is widely recognized that the risk of secondary neoplasms increases as childhood cancer survivors progress through adulthood. These are mainly hematological malignancies, and recurrent chromosome translocations are commonly detected in such cases. On the other hand, while secondary epithelial malignancies have sometimes been reported, chromosome translocations in these epithelial malignancies have not. A 33-year-old man who had been diagnosed with acute lymphoblastic leukemia and treated with chemotherapy almost 20 years earlier was diagnosed with lung adenocarcinoma. After chromosomal rearrangement of echinoderm microtubule-associated protein-like 4 gene and the anaplastic lymphoma kinase gene was detected in this adenocarcinoma, he responded to treatment with crizotinib. It was therefore concluded that this echinoderm microtubule-associated protein-like 4 gene-anaplastic lymphoma kinase gene-positive lung adenocarcinoma was a secondary epithelial malignancy.

Severe, but manageable hypoxia caused by bronchospasm induced by bevacizumab.

Bevacizumab has a lower risk of treatment‐related infusion reactions than other humanized monoclonal antibodies, and bronchospasm induced by bevacizumab has not been reported. We administered bevacizumab 15 mg/kg over 90 min infusion to a 34 year‐old man with lung adenocarcinoma and childhood asthma. Then, grade 3 hypoxia developed and improved spontaneously. This reversible obstructive lung disorder was confirmed using a flow‐volume loop, and the patient was diagnosed as having a bronchospasm due to infusion reaction of bevacizumab. This bronchospasm was easily manageable and preventable using an oral bronchodilator and an inhalant combination product, and the patient continued with bevacizumab therapy until the disease progression.

Phase I/II study of amrubicin and nedaplatin in patients with untreated, advanced, non-small cell lung cancer.

A phase I/II study of combination chemotherapy with amrubicin and nedaplatin for patients with untreated, advanced, non-small cell lung cancer (NSCLC) was conducted. Amrubicin was given on days 1-3, with nedaplatin given on day 1. The treatment was repeated every 3 weeks. In the phase I trial, the initial amrubicin dose of 25 mg/m2 was escalated in 5-mg/m2 increments until the maximum tolerated dose was reached, with the dose of nedaplatin fixed at 100 mg/m2. In the phase II trial, the primary endpoint was the overall response rate (ORR), assuming 20% for a standard therapy and 40% for a target therapy (α = 0.05 and β = 0.20), and the estimated required total number of patients was 35. In the phase I study, nedaplatin 100 mg/m2 and amrubicin 25 mg/m2 was recommended. In the phase II study, 17 out of 35 patients achieved a partial response, and the ORR was 48.6%. Grade 3/4 neutropenia, grade 3 anemia and grade 3/4 thrombocytopenia occurred in 62.9, 11.4 and 11.4% of cycles, respectively. Febrile neutropenia occurred in 5 cycles (3.9%) and all cases were manageable. The recommended dose of this combination is well tolerated and effective in patients with advanced NSCLC.