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951.
MASAMICHI NAKAI SHIGERU TAKAUCHI TOORU YAMAGUCHI TOSHIO KAWAMATA KIYOSHI MAEDA CHIKAKO TANAKA 《Pigment cell & melanoma research》1997,10(5):304-309
The A375 cell line, derived from human malignant melanoma, has characteristics of interleukin-6 (IL-6) production. By using this cell line, we have investigated a murine metastasis model of IL-6-producing tumors to the brain by injecting A375 cells directly into the left cardiac ventricle. Nude mice were anesthetized with intraperitoneal injection of pentobarbital sodium. Next, A375 cells suspended in phosphate-buffered saline (PBS) were injected into the left cardiac ventricle of mice. An intracardiac injection of 105 cells developed tumor colonies in the brain after 4 to 6 weeks. Metastatic cells were found in every lobe of the brain. An immunocytochemical study revealed IL-6 production by A375 cells at the metastatic sites in the brain. By the transfection of genes encoding proteins into A375 cells, a novel model of protein expression in the brain in vivo could be constructed. Our system does not require great skill. Our experimental model will facilitate future studies of the local effects of proteins in the brain. 相似文献
952.
Carmel Daly Seamus Coyle Shirley McBride Lorraine O'Driscoll Noel Daly Kevin Scanlon Martin Clynes 《Cytotechnology》1996,19(3):199-205
Anmdr1 hammerhead was introduced into two adriamycin-selected multi-drug resistant human lung cell lines both of which over-express p-glycoprotein. Expression of the ribozyme resulted in a decrease inmdr1 mRNA expression and an increase in drug sensitivity in both cell lines. This would suggest that the use of specific ribozymes may represent an effective and specific approach in order to restore cellular sensitivity towards anti-cancer drugs. 相似文献
953.
We have recently (Kawakami et al, Immunol. Lett. 1995;46: 143) demonstrated that unusual Mac-1+CD4?CD8? T cells bearing αβ antigen receptor (Mac-1+ αβ T cells) reside in a considerable proportion in murine lungs. The present study was performed to examine the dynamics of accumulation of these cells in the lungs following intravenous administration of Mycobacterium bovis BCG (BCG). Mac-1+ αβ T cells accumulated rapidly 24 hr after infection, followed by a gradual increase over the observation period of 15 days. Furthermore, the expression of Ia, ICAM-1 and FcγR II/III on their surface intensified dramatically after BCG infection. The kinetics of enhancement of Ia expression was slower than that of ICAM-1, with the maximum level attained in one day in the latter molecule but in two weeks in the former. Neutralization of endogenous IFN-γ by specific mAb completely blocked the augmented expression of Ia on Mac-1+ αβ T cells after BCG infection, but did not have any significant effect on that of ICAM-1. In contrast, in vivo administration of IFN-γ enhanced the expression of ICAM-1 as well as that of Ia. Our results indicate that accumulation of Mac-1 αβ T cells within the lung is associated with a differential change in the expression of surface antigens, and suggest that these cells may play a role in the host defense against mycobacterial infection. 相似文献
954.
OBJECTIVE: Fine needle aspiration cytology (FNAC) in combination with radiological examination has recently gained clinical recognition for evaluating skeletal lesions. We evaluated our experience with the use of FNA in diagnosing bone lesions with emphasis on areas of difficulty and limitations. MATERIALS AND METHODS: Over a period of 5 years FNA was performed in 66 cases of bone lesions. Aspirations were done by cytopathologists using 22-gauge needle. Out of 66 cases unsatisfactory aspirate was obtained in 12 cases. Cytohistological correlation was available in 19 cases. RESULTS: Adequate aspirates were categorized into neoplastic (27 cases) and non-neoplastic (27 cases) lesions. Of the 27 neoplastic aspirates, 20 were malignant (12 primary, 8 metastatic deposits) and 7 were benign. In the malignant group osteosarcoma was correctly diagnosed in 3 cases while other 3 were labeled as sarcoma NOS because of lack of osteoid. Metastatic deposits were sub-typed in 6 cases; from renal cell carcinoma (3 cases), proststic adenocarcinoma, follicular carcinoma thyroid, and squamous cell carcinoma. Neoplastic group comprised of 6 cases of cysts and 21 cases of chronic osteomyelitis. Thirteen cases were diagnosed as tuberculous osteomyelitis. CONCLUSIONS: FNA is a frequent indication in metastases in the bone where distinct cytologic features can even identify an unknown primary. However, diagnosis of primary tumours of the bone is limited by precise subtyping of the tumours. FNA has emerged as a cost effective tool for initial diagnosis of both neoplastic and non-neoplastic lesions of the bone. 相似文献
955.
目的探讨小细胞肺癌患者发生脑转移的相关因素。方法回顾性分析118例病理确诊的小细胞肺癌患者,比较发生脑转移与未发生脑转移两组小细胞肺癌患者的临床特征。结果单因素分析发现诊断时转移器官数、NSE、LDH、一线化疗周期数、一线化疗疗效、是否接受预防性全脑放疗与患者是否发生肺癌脑转移相关。多因素分析结果显示转移器官数、NSE、一线化疗周期数与接受预防性全脑放疗是脑转移的独立影响因素。结论转移器官数≥2[OR:4.53,(95%CI:1.19~17.26),P=0.027]和NSE大于正常值4倍[OR:2.70,(95%CI:1.05~6.94),P=0.039]是小细胞肺癌患者发生脑转移的独立危险因素。一线化疗周期数≥6个周期[OR:0.28,(95%CI:0.11~0.68),P=0.005]与接受预防性全脑放疗[OR:0.49,(95%CI:0.01~0.42),P=0.006]是脑转移的保护因素。 相似文献
956.
Lung cancer is a clinically difficult disease with rising disease burden around the world. Unfortunately, most lung cancers present at a clinically advanced stage. Of these cancers, many also present with brain metastasis which complicates the clinical picture. This review summarizes current knowledge on the molecular basis of lung cancer brain metastases. We start from the clinical perspective, aiming to provide a clinical context for a significant problem that requires much deeper scientific investigation. We review new research governing the metastatic process, including tumor cell signaling, establishment of a receptive tumor niches in the brain and evaluate potential new therapeutic options that take advantage of these new scientific advances.Lung cancer remains the largest single cause of cancer mortality in the United States (Siegel et al., 2015). This continues to be the clinical picture despite significant advances in therapy, including the advent of targeted molecular therapies and newly adopted immunotherapies for certain subtypes of lung cancer. In the vast majority of cases, lung cancer presents as advanced disease; in many instances, this advanced disease state is intimately associated with micro and macrometastatic disease (Goldberg et al., 2015). For both non-small cell lung cancer and small cell lung cancer patients, the predominant metastatic site is the brain, with up to 68% of patients with mediastinal lymph node metastasis eventually demonstrating brain metastasis (Wang et al., 2009).The frequency (incidence) of brain metastasis is highest in lung cancers, relative to other common epithelial malignancies (Schouten et al., 2002). Other studies have attempted to predict the risk of brain metastasis in the setting of previously non-metastatic disease. One of the largest studies to do this, analyzing historical data from 1973 to 2011 using the SEER database revealed a 9% risk of patients with previously non-metastatic NSCLC developing brain metastasis over the course of their disease, while 18% of small cell lung cancer patients without previous metastasis went on to develop brain metastasis as their disease progressed (Goncalves et al., 2016).The reasons underlying this predilection for the central nervous system, as well as the recent increase in the frequency of brain metastasis identified in patients remain important questions for both clinicians and basic scientists. More than ever, the question of how brain metastasis develop and how they can be treated and managed requires the involvement of interdisciplinary teams—and more importantly—scientists who are capable of thinking like clinicians and clinicians who are capable of thinking like scientists. This review aims to present a translational perspective on brain metastasis. We will investigate the scope of the problem of brain metastasis and the current management of the metastatic disease process in lung cancer. From this clinical starting point, we will investigate the literature surrounding the molecular underpinnings of lung tumor metastasis and seek to understand the process from a biological perspective to generate new hypotheses. 相似文献
957.
Janina Kulka Borbála Székely Lilla V. Lukács Orsolya Kiss Anna-Mária T?kés Eszter Vincze Eszter Turányi János Fillinger Zoltán Hanzély Gabriella Arató Miklós Szendr?i Balázs Gy?rffy A. Marcell Szász 《The journal of histochemistry and cytochemistry》2016,64(4):256-267
Parallel studies of primary breast carcinomas and corresponding distant metastases samples reveal considerable differences. Our aim was to highlight this issue from another perspective and provide further data based on 98 patient samples: 69 primary breast carcinoma and 85 distant metastases from bone, central nervous system (CNS) and lung (56 paired). Two independent series of immunohistochemical reactions with different antibodies for estrogen receptor (ER), progesterone receptor (PgR) and human epidermal growth factor receptor 2 (Her2), along with HER2 fluroscence in situ hybridization (FISH) were performed on tissue microarrays to classify breast carcinoma and distant metastases samples into Luminal A, Luminal B-proliferating, Luminal B-HER2+, HER2+ and triple negative (TNBC) surrogate breast cancer groups. Correlation and agreement between the two assessments of ER and PgR were fair-to-moderate, and almost perfect for HER2 and Ki67. There was 40% discordance concerning immunophenotype between breast carcinomas and distant metastases. Most common metastatic site of ER+ breast carcinoma was the skeletal system (59.2%), whereas that of TNBCs was the CNS (58.8%) and lungs (23.5%). Distant metastases in bones were mostly luminal (54.3%), in the CNS, Luminal B (53.2%), and in the lung, TNBC (37.5%). The change of drugable properties of primary breast cancers in the respective bone and CNS metastases suggests that characterization of the metastasis is necessary for appropriate treatment planning. 相似文献
958.
Ming-Hui Fan Qiang Zhu Hui-Hua Li Hyun-Jeong Ra Sonali Majumdar Dexter L. Gulick Jacob A. Jerome Daniel H. Madsen Melpo Christofidou-Solomidou David W. Speicher William W. Bachovchin Carol Feghali-Bostwick Ellen Puré 《The Journal of biological chemistry》2016,291(15):8070-8089
Idiopathic pulmonary fibrosis is a disease characterized by progressive, unrelenting lung scarring, with death from respiratory failure within 2–4 years unless lung transplantation is performed. New effective therapies are clearly needed. Fibroblast activation protein (FAP) is a cell surface-associated serine protease up-regulated in the lungs of patients with idiopathic pulmonary fibrosis as well as in wound healing and cancer. We postulate that FAP is not only a marker of disease but influences the development of pulmonary fibrosis after lung injury. In two different models of pulmonary fibrosis, intratracheal bleomycin instillation and thoracic irradiation, we find increased mortality and increased lung fibrosis in FAP-deficient mice compared with wild-type mice. Lung extracellular matrix analysis reveals accumulation of intermediate-sized collagen fragments in FAP-deficient mouse lungs, consistent with in vitro studies showing that FAP mediates ordered proteolytic processing of matrix metalloproteinase (MMP)-derived collagen cleavage products. FAP-mediated collagen processing leads to increased collagen internalization without altering expression of the endocytic collagen receptor, Endo180. Pharmacologic FAP inhibition decreases collagen internalization as expected. Conversely, restoration of FAP expression in the lungs of FAP-deficient mice decreases lung hydroxyproline content after intratracheal bleomycin to levels comparable with that of wild-type controls. Our findings indicate that FAP participates directly, in concert with MMPs, in collagen catabolism and clearance and is an important factor in resolving scar after injury and restoring lung homeostasis. Our study identifies FAP as a novel endogenous regulator of fibrosis and is the first to show FAP''s protective effects in the lung. 相似文献
959.
《Peptides》2016
Excessive inflammatory response induced by lipopolysaccharide (LPS) plays a critical role in the development of acute lung injury (ALI). Paralemmin-3 (PALM3) is a novel protein that can modulate LPS-stimulated inflammatory responses in alveolar epithelial A549 cells. However, it remains unclear whether it is involved in the progression of ALI in vivo. Therefore, we studied the role of PALM3 in the pathogenesis of ALI induced by LPS. ALI was induced by LPS peritoneal injection in C57BL/6J mice. Lentivirus-mediated small interfering RNA (siRNA) targeting the mouse PALM3 gene and a negative control siRNA were intranasally administered to the mice. We found that the expression of PALM3 was up-regulated in the lung tissues obtained from the mouse model of LPS-induced ALI. The LPS-evoked inflammatory response (neutrophils and the concentrations of proinflammatory cytokines [IL-6, IL-1β, TNF-α, MIP-2] in the bronchoalveolar lavage fluid [BALF]), histologic lung injury (lung injury score), permeability of the alveolar capillary barrier (lung wet/dry weight ratio and BALF protein concentration) and mortality rates were attenuated in the PALM3 siRNA-treated mice. These results indicate that PALM3 contributes to the development of ALI in mice challenged with LPS. Inhibiting PALM3 through the intranasal application of specific siRNA protected against LPS-induced ALI. 相似文献
960.