• Tuberculosis and Respiratory Diseases
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• v.43 no.1
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• pp.46-53
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• 1996

Background: Endotoxin or lipopolysaccharide(LPS) can prime phagocytic cells such as polymorphonuclear leukocytes, monocytes or animal peritoneal macrophages to generate increased amounts of secretory products such as oxygen free radicals and tumor necrosis factor, which play an important role in developing adult respiratory distress syndrome in gram negative sepsis. Human alveolar macrophages(HAM) are continuously exposed to various stimuli inhaled into the alveoli, and the response to LPS might be different in HAM. Therefore, we investigated the effect of LPS pre-exposure on HAM adhered to plastic surface and A549 cell(type II human alveolar epithelial cell line) monolayer. Methods: HAM were isolated from bronchoalveolar lavage fluid from normal lung of the patients with localized lung cancer and esophageal cancer. LPS was exposed to HAM for 2hrs before or after adherence to plastic surface of 24-well Linbro plate and A549 cell monolayer. And then HAM was stimulated with PMA(phorbol myristate acetate) or fMLP(N-formyl-methionylleucyl-phenylalanine). The amount of hydrogen peroxide($H_2O_2$) production in the supernatant was measured on the principle of peroxidase-dependent oxidation of phenol red by hydrogen peroxide. Results: LPS pre-exposure could not enhance $H_2O_2$ production in neither HAM adhered to plastic surface nor one to A549 cell monolayer. But LPS even in the absence of PMA or fMLP stimulation directly increased $H_2O_2$ release in HAM if added after the adherence to A549 cell monolayer. Conclusion: Endotoxin does not prime HAM, but may directly activate HAM adhered to alveolar epithelial cells. Further investagation will be necessary.

• Radiation Oncology Journal
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• v.22 no.1
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• pp.1-10
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• 2004

Locally advanced (Stage III) non-small cell lung cancer (NSCLC) accounts for approximately one third of all cases of NSCLC. Few patients with locally advanced NSCLC present with disease amenable to curative surgical resection. Historically, these patients were treated with primary thoracic radiation therapy (RT) and had poor long term survival rates, due to both progression of local disease and development on distant metastases. Over the last two decades, the use of multidisciplinary approach has improved the outcome for patients with locally advanced NSCLC. Combined chemoradiotherapy is the most favored approach for treatment of locally advanced unresectable NSCLC. There are two basic treatment protocols for administering combined chemotherapy and radiation, sequential versus concurrent. The rationale for using chemotherapy is to eliminate subclinical metastatic disease while improving local control. Sequential use of chemotherapy followed by radiotherapy has improved median and long term survival compared to radiation therapy alone. This approach appears to decrease the risk of distant metastases,, but local failure rates remain the same as radiation alone. Concurrent chemoradiotherapy has been studied extensively. The potential advantages of this approach may include sensitization of tumor cells to radiation by the administration of chemotherapy, and reduced overall treatment time compared to sequential therapy; which is known to be important for improving local control in radiation biology. This approach Improves survival primarily as a result of improved local control. However, it doesn't seem to decrease the risk of distant metastases probably because concurrent chemoradiation requires dose reductions in chemotherapy due to increased risks of acute morbidity such as acute esophageal toxicity. Although multidisciplinary therapy has led to improved survival rates compared to radiation therapy alone and has become the new standard of care, the optimal therapy of locally advanced NSCLC continues to evolve. The current issues in the multidisciplinary management of locally advanced NSCLC will be reviewed in this report.