鈴木 秀海

Orthotopic lung transplantation in rats was first reported by Asimacopoulos and colleagues in 1971 (1). Currently, this method is well accepted and standardized not only for the study of allo-rejection but also between syngeneic strains for examining mechanisms of ischemia-reperfusion injury after lung transplantation. Although the application of the rat and other large animal model (2) contributed significantly to the elucidation of these studies, the scope of those investigations is limited by the scarcity of knockout and transgenic rats. Due to no effective therapies for obliterative bronchiolitis, the leading cause of death in lung transplant patients, there has been an intensive search for pre-clinical models that replicate obliterative bronchiolitis. The tracheal allograft model is the most widely used and may reproduce some of the histopathologic features of obliterative bronchiolitis (3). However, the lack of an intact vasculature with no connection to the recipient's conducting airways, and incomplete pathologic features of obliterative bronchiolitis limit the utility of this model (4). Unlike transplantation of other solid organs, vascularized mouse lung transplants have only recently been reported by Okazaki and colleagues for the first time in 2007 (5). Applying the basic principles of the rat lung transplant, our lab initiated the obliterative bronchiolitis model using minor histoincompatible antigen murine orthotopic single-left lung transplants which allows the further study of obliterative bronchiolitis immunopathogenesis(6).

BACKGROUND: Direct allorecognition, i.e., donor lung-derived dendritic cells (DCs) stimulating recipient-derived T lymphocytes, is believed to be the key mechanism of lung allograft rejection. Myeloid (cDCs) and plasmacytoid (pDCs) are believed to have differential effects on T cell activation. However, the roles of each DC type on T cell activation and rejection pathology post lung transplantation are unknown. METHODS: Using transgenic mice and antibody depletion techniques, either or both cell types were depleted in lungs of donor BALB/c mice (H-2(d)) prior to transplanting into C57BL/6 mice (H-2(b)), followed by an assessment of rejection pathology, and pDC or cDC-induced proliferation and cytokine production in C57BL/6-derived mediastinal lymph node T cells (CD3+). RESULTS: Depleting either DC type had modest effect on rejection pathology and T cell proliferation. In contrast, T cells from mice that received grafts depleted of both DCs did not proliferate and this was associated with significantly reduced acute rejection scores compared to all other groups. cDCs were potent inducers of IFNγ, whereas both cDCs and pDCs induced IL-10. Both cell types had variable effects on IL-17A production. CONCLUSION: Collectively, the data show that direct allorecognition by donor lung pDCs and cDCs have differential effects on T cell proliferation and cytokine production. Depletion of both donor lung cDC and pDC could prevent the severity of acute rejection episodes.

OBJECTIVE: It is controversial whether lung regeneration contributes to compensatory lung growth after pulmonary resection in mature individuals. The objectives of this study were to clarify the molecular mechanisms that regulate the process of compensatory lung growth and investigate the influence of transplantation of lung cells enriched in alveolar type II cells on compensatory lung growth. METHODS: Serial changes of morphology and gene expression were examined in the remnant right lung after pneumonectomy in adult male Wistar rats. One day after surgery, animals received endotracheal transplants of rat lung cells enriched in alveolar type II cells at a dose of 2.5 × 10(6) cells. Serial morphologic changes were examined in comparison with pneumonectomy alone. Engraftment of lung cells was validated with a sex-mismatch model. RESULTS: The alveolar density with mean linear intercept was always lower in pneumonectomized rats than in sham surgical controls for 6 months after surgery. Microarray analysis revealed that multiple genes related to proliferation (but not specific alveolar development) were initially up-regulated and then returned to normal after 1 month. In the pneumonectomized rats with transplantation, the alveolar density was equivalent to that in the sham controls. Engraftment of the transplanted cells from male donors in the alveoli of female recipients was proven by detection of Y-chromosome positive cells and quantified by real-time polymerase chain reaction for the Sry gene. This occurred in pneumonectomized rats but not in sham controls. CONCLUSIONS: We postulate that lung cell transplantation stimulates lung regeneration in the remnant lung after pneumonectomy in mature rats.

BACKGROUND: : Radiofrequency ablation (RFA) has emerged as a potential alternative for surgery in clinical oncology. This animal experiment was conducted to evaluate the feasibility, safety, and effectiveness of transbronchial RFA in the treatment of lung tumor. METHODS: : VX2 lung cancer model was established in Japanese white rabbits by transbronchial injection of tissue clot suspension. After waiting for tumor growth to approximately 10 to 20 mm in diameter, transbronchial RFA was performed on VX2 tumors using the Celon-ProCurve microprobe with a 12 mm active tip, a diameter of 1.3 mm, without cooled-tip electrode under the guidance of biplane x-ray scanning. At first, the power of delivery of RFA was increased in a stepwise manner beginning at 1 W/min up to a maximum of 4 W/min, to seek appropriate power deposition. Next, the extent of ablation under determined power deposition was examined for various time periods. The therapeutic efficacy was evaluated by grossly and pathologically 1 week after transbronchial RFA. RESULTS: : All rabbits tolerated the experimental procedures well. Transbronchial RFA at 2 W/min for 20 minute was the most effective setting in this study. Application of more than 2 W/min was not technically feasible using this equipment, leading to destruction of the probe due to high resistance. In transbronchial RFA at 2 W/min condition, the extent of ablation depended on the duration of ablation. CONCLUSIONS: : This study demonstrates the potential of transbronchial RFA therapy for treatment of lung tumors. Probe improvement and additional study will be required for further progress.

PURPOSE: In patients with lung cancer accompanied by idiopathic pulmonary fibrosis (IPF), acute exacerbation of the IPF often occurs after pulmonary resection; however, few studies have been done to identify its preexisting risk factors. METHODS: We analyzed the high-resolution computed tomography (HRCT) findings of IPF to identify the radiological characteristics of IPF susceptible to acute exacerbation after lung cancer surgery. We reviewed retrospectively 28 lung cancer patients with IPF who underwent pulmonary resection. Clinical data, respiratory function, HRCT findings, and historical features were compared between the acute exacerbation (n = 9) and nonexacerbation (n = 19) groups. The classification of radiological findings of IPF on HRCT was done using a scoring system of seven factors related to the interstitial shadow, including fibrosis, ground-glass opacity, and low-attenuation area. RESULTS: There were no significant differences in clinical background, respiratory function, composite physiologic index, or pathological features between the groups; however, the degree of fibrosis on preoperative HRCT was significantly higher in the exacerbation group (P < 0.003). The fibrosis score was higher on the opposite side to the lung cancer in the exacerbation group (P < 0.05). CONCLUSION: Although it is difficult to predict postoperative acute IPF exacerbation, the degree and laterality of co-existing fibrosis seem to be predictors.

Pulmonary sclerosing hemangioma is relatively rare and is usually considered a benign tumor. There have been no reports of pulmonary sclerosing hemangioma with pleural dissemination. This report presents an extremely rare case of pulmonary sclerosing hemangioma with pulmonary dissemination. A 57-year-old woman was found to have an abnormal shadow in the right lower lung field on chest X-ray. Chest computed tomography (CT) indicated a 2.5-cm mass in the right lower lobe. A bronchoscopic biopsy failed to identify malignant cells, which led to the patient undergoing an excisional lung biopsy. Intraoperative findings showed a tumor in the right lower lobe with multiple small nodules in the pleura. The pathological findings revealed that the tumor was sclerosing hemangioma with pleural dissemination. Annual follow-up CT showed irregular pleural thickness, which suggested progressive dissemination 3 years after the operation. Although pulmonary sclerosing hemangioma is regarded as a benign tumor, the potential for malignancy may be a consideration in this setting.

PURPOSE: The purpose of this study was to identify the risk factors for postoperative pulmonary complications and to develop a scoring system to predict the surgical outcomes in lung cancer patients. METHODS: Clinical data were collected from January 1990 to March 2007 for 1713 patients who underwent lung cancer surgery at Chiba University Hospital. Between January 1990 and December 2000, 1032 evaluation subjects' data were used to identify risk factors for postoperative pulmonary complications (PC). These factors were subclassified into grades to develop a scoring system to predict surgical outcomes. This scoring system was applied to 681 test patients between January 2001 and March 2007. RESULTS: Postoperative PC were present in 115 (11.1%) evaluation subjects. Multivariate analyses revealed six risk factors associated with postoperative PC: male, advanced age, preoperative interstitial pneumonia, high smoking index, combined resection, and vascular and/or bronchial reconstruction. Each risk factor was scored from 0 to 2 or 3, based on the frequency of the PC. The sum of these scores provided a total risk index (TRI: Sekine score). There was a significant correlation between the frequency of PC and the TRI (R (2) = 0.957, P < 0.0001). Fifty-one of the test subjects had PC (7.5%). They also showed a significant correlation between the PC and TRI (R (2) = 0.946, P < 0.0001). CONCLUSION: The TRI was a valuable scoring system for predicting postoperative pulmonary complications.

PURPOSE: Long-acting bronchodilators are recommended as a first-line treatment for chronic obstructive pulmonary disease (COPD), although their effects for postoperative lung cancer patients with COPD are still not well known. A prospective randomized trial was used to examine the efficacy of bronchodilators on postoperative pulmonary function and quality of life (QOL). METHODS: Twenty lung cancer patients with COPD who had lobectomies were randomized. A control group (n = 10) did not receive bronchodilators. An experimental group (n = 10) received tiotropium and salmeterol. Patients were divided into two COPD grades: stage I COPD and stage II-III COPD. Results for pulmonary function, 6-minute walking test, and the St. George's Respiratory Questionnaire (SGRQ) were compared. Diaphragmatic motion on dynamic magnetic resonance imaging was also analyzed. RESULTS: The patient demographics were similar in the two groups. Except for pulmonary function results at 2 weeks, no other parameters were significantly different. However, in stage II-III COPD, forced expiratory volume in 1 second, forced vital capacity, inspiratory capacity, the total score of the SGRQ, and diaphragmatic motion in the experimental group (n = 5) were significantly better than those in the control group (n = 4) at various time points (all P < 0.05). CONCLUSION: The daily inhalation of bronchodilators was effective for maintaining the respiratory function and QOL in lung cancer patients with moderate to severe COPD.

BACKGROUND: This retrospective study investigated long-term graft patency and outcomes for malignant diseases with invasion of the superior vena cava (SVC). METHODS: From October 1995 to November 2008, 20 patients underwent combined surgical resection of malignant tumors and the SVC with vascular reconstruction using a ringed polytetrafluoroethylene graft (8 to 12 mm) Sigmoid-curved spatulation of the graft end at the right auricle was performed to obtain a wide orifice left graft. Anticoagulation therapy was routinely administered for 3 to 6 months. Postoperative graft patency was verified at 2 to 4 weeks, 3 months, and after 12 months. Indications were lung cancer in 9 patients, thymic tumors in 8, germ cell tumors in 2, and thyroid cancer in 1. RESULTS: Procedures were single graft replacement in 9 patients, bilateral grafts in 10, and bilateral SVC grafts and 1 pulmonary artery graft in 1. All grafts were patent over a short-term period, but 1 limb of the bilateral grafts became occluded in 2 patients who received bilateral grafts during long-term follow-up. Bronchial dehiscence after lung cancer resection caused 1 in-hospital death. Mean follow-up was 44.7 months. Median survival was 22.1 months. Overall survival was 66.4% and 41.5% at 1 and 5 years, respectively. Survival for lung cancer was significantly worse at 5 years (62.5%) than thymic tumor (18.8%, p = 0.04). CONCLUSIONS: Prosthetic reconstruction of the SVC for anterior mediastinal tumors and lung cancer is feasible. Reconstruction of the SVC using a single left graft to avoid total cross-clamping of the SVC is effective.

We report three cases of synchronous multiple thymoma diagnosed at a single hospital during the 10 years since 1999. Two were accompanied by myasthenia gravis (MG). In two patients, two thymomas were detected by preoperative computed tomography (CT), and in one, a microthymoma was found incidentally on pathologic examination of a resected specimen for gross thymoma and thymus. The multiple lesions were located in the thymus, and extended thymectomy was performed via median sternotomy in all three patients. The World Health Organization subtypes of the multiple thymomas were identical in each patient; however, all were considered to be primary lesions since the larger one was well encapsulated and each tumor was apparently separated. The Masaoka stage was classified as I/I, I/I, and I/II, respectively. Postoperative clinical courses were uneventful and no recurrence was observed in any of the patients. We reviewed 16 reported cases of synchronous multiple thymoma, and discuss the pathogenesis and treatment of this unusual entity.

BACKGROUND: Lung cancer patients with chronic obstructive pulmonary disease (COPD) have a high risk of developing postoperative pneumonia (POP). This study aims to investigate the impact of COPD on POP and the trends for perioperative bronchial colonisation by micro-organisms. METHODS: A retrospective chart review was made for 626 patients who underwent lung cancer surgeries at the Chiba University Hospital between 1996 and 2005. The patients were categorised as non-COPD (n=475) and COPD (forced expiratory volume in 1s/forced vital capacity (FEV1/FVC) <70%; n=151). All the patients had sputum and bronchial bacterial cultures examined for potentially pathogenic micro-organisms (PPMs). Risk factors for POP and mortality were analysed. RESULTS: Patients with COPD had a significantly higher incidence of POP (23/151, 15.2%) than those without COPD (17/475, 3.6%) (p<0.0001). Preoperative bronchial bacterial examinations showed that 50 of 475 patients without COPD (10.5%) had positive cultures, while the results for 30 of 151 patients with COPD (19.9%) were positive (p=0.0111). Only 31 of 548 patients (5.7%) who did not show any preoperative PPMs had POP, while nine of 78 patients (11.5%) who presented preoperative PPMs had POP (p=0.0469). The PPMs that emerged postoperatively were primarily Staphylococcus aureus (and Gram-negative bacilli (94.4% of PPMs), while they were seen less frequently preoperatively (46.5% of PPMs). Multivariate analysis demonstrated that advanced age and FEV1/FVC were independent risk factors for POP. Patients with POP had significantly worse long-term survivals than those without POP (p=0.0004). CONCLUSION: COPD was a risk factor for POP. Staphylococcus aureus and Gram-negative bacilli should be targets for postoperative prophylactic antibiotic selection. Patients with POP had poor long-term survivals.

BACKGROUND: The aim of this study was to evaluate the molecular influence of chronic obstructive pulmonary diseases (COPD) on the pathogenesis of non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: The methylation profiles of 12 genes, and the epidermal growth factor receptor (EGFR) and KRAS mutations were determined for samples from 229 NSCLC patients. In addition, protein expression of EGFR and HER2 in 116 NSCLCs was analyzed based on the presence or absence of COPD. RESULTS: IL-12Rbeta2 and Wif-1 methylation and HER2 overexpression were more frequent events in the COPD group. Eighty nonmalignant lung tissues had no correlation with any molecular changes between the COPD and the non-COPD group. EGFR mutation was significantly higher in the non-COPD group, while EGFR expression was inversely correlated with %FEV1.0. In the COPD group, unmethylated SPARC and sFRP-2 genes or a negative CpG island methylator phenotype (CIMP) was a negative prognostic factor, while methylation of p16(INK4A) and WNT antagonist genes was a negative prognostic factor in the non-COPD group. CONCLUSIONS: Novel characteristics of COPD-related NSCLC were identified by examination of methylation profiles and alterations of EGFR signaling. In consideration of the high sensitivity to smoking in patients with COPD, NSCLC with COPD might be a distinct population of smoke-related NSCLC, the genetic profile of which is quite different from non-COPD NSCLC.

We report a case of a mediastinal teratoma associated with acute mediastinitis that required an emergency operation. These tumors cause a variety of complications, but reports of acute mediastinitis are rare. A 24-year-old woman was admitted to our hospital for complaints of chest pain and fever and was subsequently diagnosed as having an anterior mediastinal tumor. Follow-up computed tomography showed rapidly progressing acute mediastinitis, which was diagnosed as a perforation of the teratoma. We performed emergency surgical extirpation of the tumor and mediastinal drainage. The histopathologic diagnosis was a mature teratoma that included pancreatic tissue. Although the apparent site of the rupture was not obvious, there was a wide area of acute inflammation in the mediastinal adipose tissue. The patient did well and was discharged from the hospital without major complications.

Background: The functional criteria for curative surgery for patients with non-small cell lung cancer (NSCLC) and coexisting chronic obstructive pulmonary disease (COPD) remain controversial. We aimed to clarify long-term outcomes after resection. Methods: Between January 1990 and April 2005, 36 consecutive patients with NSCLC and severe COPD underwent pulmonary resection. All had severe (30-50% pred FEV1) or very severe COPD (30% &gt; pred FEV1) preoperatively. Survival, short- and long-term complications were analyzed retrospectively. Prognostic factors were also analyzed. Results: The 5-year survival rate of these patients was significantly worse than that of patients with better pulmonary function (50% &lt; pred FEV1) (p &lt; 0.0001). Patients with interstitial pneumonia (1P) had a significantly poorer prognosis (p = 0.0099). With regard to long-term complications three months after surgery, 30% of patients reported worsening of dyspnea, and 20% experienced pneumonia recurrence. No deaths were related to COPD progression. Conclusion: Patients with stage IA NSCLC and severe COPD may undergo curative surgical resection; however, postoperative complications and long-term survival remain unsolved problems. IP is a contraindication for surgery in patients with severe COPD.

Several studies have described p16INK4A and prostaglandin E2 (PGE2) co-alterations in various solid tumors, including non-small cell lung cancer (NSCLC). In this study, we examined the correlation between PGE2 receptor 2 (EP2) expression and p16INK4A methylation in NSCLC, and the association with clinicopathological features and prognostic significance. We retrospectively reviewed 88 NSCLC patients who underwent resection from July 1993 to May 1997. The tumors included 43 adenocarcinomas, 39 squamous cell carcinomas, and 6 large cell carcinomas. EP2 expression was determined by immunostaining, and p16INK4A methylation was analyzed by methylation specific PCR. EP2 was overexpressed in 44% of NSCLC patients, 61% of adenocarcinoma cases, 28% of squamous cell carcinoma cases, and 33% of large cell carcinoma cases. EP2 expression positively correlated with lymph node metastasis (P=0.034), especially in patients with squamous cell carcinoma (P<0.009). Methylation of p16INK4A was detected in 34% of NSCLC patients, 23% of adenocarcinoma cases, 44% of squamous cell carcinoma cases, and 50% of large cell carcinoma cases. In patients with squamous cell carcinoma, EP2 overexpression correlated with poor prognosis with a relative risk of 2.4 (confidence interval 2.1-51.8, P<0.003), and positively correlated with p16INK4A methylation (P<0.024). Adenocarcinoma patients with p16INK4A methylation had poor prognosis with a relative risk of 2.4 (confidence interval 1.8-69.7, P<0.009), but this was not correlated with EP2 expression. In conclusion, EP2 overexpression was common in NSCLCs, especially in adenocarcinomas. Synchronous alteration of p16INK4A and EP2 may accelerate progression of squamous cell carcinomas. These two alterations may differentially affect pathogenesis among subtypes of NSCLC.

Chemokines play an important role in the pathogenesis of non-small cell lung cancer (NSCLC). However, aberrant methylation of CXCL12 has not been examined in NSCLC. CXCL12 mRNA expression and methylation were examined in 17 NSCLC cell lines by RT-PCR and methylation-specific PCR (MSP). MSP was performed on 236 tumor specimens from NSCLC patients who received curative intent surgery. CXCL12 and CXCR4 protein expression was examined in 90 of the 236 NSCLC specimens by immunohistochemistry. Down-regulation of CXCL12 expression was found in 10 of 17 (59%) NSCLC cell lines compared with normal bronchial cells. Treatment of 8 expression-negative cell lines with a demethylating agent restored expression in all cases. Twelve cell lines (71%) showed aberrant methylation, and good concordance between methylation and expression was present. Aberrant methylation occurred in 85 out of 236 (36%) primary NSCLCs in a tumor-specific manner. In multivariate analysis, CXCL12 methylation correlated strongly and independently with prognosis both in all patients with NSCLCs and in those with stage I NSCLCs (hazard ratio=1.68, P=0.015 and hazard ratio=3.58, P=0.017). Secreted protein CXCL12 and its receptor CXCR4 were abundant in NSCLC cells (72 out of 90, 80%; 57 out of 90, 63%) and correlated with the progression of NSCLCs. In conclusion, epigenetic silencing of CXCL12 is a frequent event in NSCLCs, and could be an independent and powerful prognostic marker in patients with NSCLCs and those with stage I disease. Analysis for CXCL12 may provide novel opportunities for prognosis and therapy of resected NSCLCs.