Advances in the Molecular Biology of Malignant Mesothelioma

Malignant mesothelioma (MM) is a highly aggressive tumor with a dismal prognosis. The incidence of MM is increasing as a result of widespread exposure to asbestos. As for the molecular alterations that occur in MM, chromosome alterations including homo-deletion of the P16 and P14 genes located in the 9p21 are well known. Mutations are rare in the P53 and Ras genes, which are frequently present in epithelial solid tumors. However, mutations are frequently present in the neurofi bromatosis type 2 gene. Epigenetic alterations including DNA methylation have been found in the MM, the profi le of which is diff erent from that of lung cancer, although differential diagnosis is sometimes clinically difficult. As in other malignant tumors, genes that are related to immortalization, proliferation, metastasis, angiogenesis, and anti-apoptosis are also overexpressed in MM, contributing to its malignant phenotype. It is of interest that simian virus 40 has been implicated to be one of the causative factors of MM in western countries. Although the causative role of asbestos is well-known in MM, much less information is available for MM than for other malignant tumors regarding the molecular alterations that occur in the disease. In terms of future tasks, it will be necessary to apply the knowledge that is learned about molecular alterations to clinical practice and to further elucidate the pathogenesis of MM with extensive research.</p

Dry Small Pleural Dissemination of Adenocarcinoma of the Lung Preoperatively Detected by PET/CT: A Report of Two Cases

Dry pleural dissemination in non-small cell lung cancer, defined as solid pleural metastasis of lung cancer without pleural eff usion, is a condition occurring in T4 lung cancer. Positron emission tomography (PET) has been reported to be useful for the diagnosis and staging of lung cancer. It has been reported that positive findings on PET scans of indeterminate pleural abnormalities at computed tomography (CT) are sensitive to malignancy. We encountered two cases of dry small pleural dissemination of adenocarcinoma of the lung preoperatively detected by PET/CT. A 75-year-old man and a 66-year-old man underwent CT scan, which demonstrated solitary tumor in the lung, an enlarged mediastinal lymph node, and a small pleural nodule less than 10 mm in size, all of which were positive findings on the fluorine 18 fluorodeoxyglucose (FDG) PET portion of an integrated PET/CT. Both patients underwent thoracoscopic biopsy of the dry pleural nodule revealing dissemination of adenocarcinoma of the lung (T4). Whereas histological thoracoscopic diagnosis remains mandatory before planning treatment, our cases may suggest that PET/CT will be useful as a screening modality for dry pleural dissemination of lung cancer.</p

Optimal Temperature of Graft Preservation after ex Vivo Gene Transfer in Lung Isografts

The aim of this study was to determine the optimal temperature of graft preservation after ex vivo gene transfer to rat lung isografts. Left lungs were harvested and infused with cationic lipid/LacZ-DNA complex via the pulmonary artery, and the grafts were stored for 4h. The grafts (n＝7) were allocated into groups IﾝIV according to the storage temperature:4℃, 10℃, 16℃, and 23℃, respectively. Forty-eight h after orthotopic transplantation, the arterial blood gas was analyzed and the peak airway pressure (PAP) and the level of LacZ protein production in the grafts were measured by reverse transcription polymerase chain reaction. After reperfusion, the grafts were stained with hematoxylin and eosin. The grafts in groups III and IV showed more deterioration as evidenced by decreased arterial oxygen tension, increased PAP, and predominant infiltration of inflammatory cells compared with groups I and II. The level of LacZ production was significantly lower in group I than in groups IIﾝIV. The optimal temperature of lung graft preservation after ex vivo gene transfer was determined to be 10℃, balancing considerations of lung injury and efficiency of transgene expression.</p

Effects of adenoviral-mediated hepatocyte growth factor on liver regeneration after massive hepatectomy in rats

Resection is the only curative treatment for liver metastasis of colorectal cancers. Despite the supreme regenerative potential of the liver, major hepatectomy sometimes leads to liver failure, and the limitation of resectable liver volumes makes advanced tumors inoperable. This study was attempted to promote liver regeneration using hepatocyte growth factor (HGF) gene transfection by venous-administered adenovirus and to improve the survival of rats after massive hepatectomy. The adenovirus that encodes HGF was administered to rats before 85%-hepatectomy. The administration of HGF gene improved the survival of rats after massive hepatectomy, while the administration of control adenovirus deteriorated their survival. Gene transfection of HGF showed up-regulation of serum HGF, stimulation of hepatocellular proliferation and rapid liver regeneration. Moreover, HGF administration reduced apoptosis of hepatocytes. The administration of HGF gene prevented liver dysfunction after major hepatectomy and may be a new assist for surgery.</p

Functional evaluation of lung by Xe-133 lung ventilation scintigraphy before and after lung volume reduction surgery (LVRS) in patients with pulmonary emphysema.

We evaluated the respiratory functions of patients with pulmonary emphysema who underwent lung volume reduction surgery (LVRS) by the mean transit time (MTT) with Xe-133 lung ventilation scintigraphy, forced expiration volume in 1 sec (FEV1.0), residual volume (RV), distance walked in 6 min (6-min walk), and the Hugh-Jones classification (H-J classification) before and after LVRS. In 69 patients with pulmonary emphysema (62 men, 7 women; age range, 47-75 years; mean age, 65.4 years +/- 6.1, preoperative H-J classification, III (two were II)-V) who underwent LVRS, all preoperative and postoperative parameters (MTT 3 weeks after LVRS and the others 3 months after LVRS) were judged statistically by the Wilcoxon signed-ranks test and Odds ratio. Every postoperative parameter was improved with a significant difference (P &#60; 0.05) compared to preoperative parameters. MTT at 3 weeks after LVRS was not associated with %FEV1.0 and the H-J classification at 3 months after LVRS, but was associated with RV and a 6-min walk at 3 months after LVRS. MTT was useful for the clinical evalution of aerobic capability after LVRS.</p

Sleeve basal segmentectomy with pulmonary artery division for lung cancer: how to do it.

Sleeve segmentectomy was originally developed to preserve the lung volume in patients who were unable to tolerate lobectomy. We herein report an immunocompromised patient with potentially curable peripheral squamous cell carcinoma in whom sleeve basal segmentectomy was performed for a 1.8-cm tumor with endobronchial growth that occluded B7 and invaded the inlet of the middle lobar bronchus and B6. To provide sufficient surgical exposure for complex double-barrel reconstruction after segmentectomy, A6 was divided and reconstructed after the anastomosis was complete. This technique may be applicable to other peripheral bronchial reconstructions to minimize blood flow disruption to bronchial anastomosis