Soluble Fas in malignant pleural effusion and its expression in lung cancer cells

• Published in: Cancer science Vol. 94; no. 3; pp. 302 - 307
• Main Authors: Mitani, Kayo, Nishioka, Yasuhiko, Yamabe, Kazue, Ogawa, Hirohisa, Miki, Toyokazu, Yanagawa, Hiroaki, Sone, Saburo
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01-03-2003; Blackwell; John Wiley & Sons, Inc
• Subjects: Actins - genetics; Apoptosis; Base Sequence; Biological and medical sciences; Cell culture; Cell surface; Cell Survival - immunology; Cytotoxicity; DNA Primers; DNA, Complementary - genetics; Effector cells; fas Receptor - analysis; fas Receptor - genetics; Flow cytometry; Humans; Immunosuppression; Jurkat Cells; Lung cancer; Lung Neoplasms - genetics; Lung Neoplasms - immunology; Lung Neoplasms - pathology; Medical sciences; mRNA; Pleural effusion; Pleural Effusion - genetics; Pleural Effusion - immunology; Pleural Effusion - pathology; Pneumology; RNA, Messenger - genetics; Tuberculosis; Tuberculosis - genetics; Tumor cell lines; Tumor cells; Tumors of the respiratory system and mediastinum; Human; Transmembrane protein; Lung disease; Fas antigen; Respiratory disease; Soluble form; Gene expression; Bronchopulmonary malignant tumor; Malignant effusion; Bronchus disease; Genetics; Pleural disease; Pleura; Biological receptor
• ISSN: 1347-9032; 1349-7006
• DOI: 10.1111/j.1349-7006.2003.tb01437.x

Soluble Fas (sFas) has the ability to block Fas‐mediated apoptosis, suggesting that sFas at tumor sites might inhibit tumor cell‐killing by immune effector cells. We examined the sFas level in pleural effusion associated with lung cancer. The level of sFas in malignant pleural effusion was significantly higher than those in transudate and tuberculous pleural effusion. There was no significant difference in the sFas concentration among various histological types of lung cancer. The cytotoxicity mediated by anti‐Fas agonistic antibody against Jurkat cells was inhibited by the addition of malignant pleural effusion, being inversely correlated with the sFas concentration. When Fas expression was examined using flow cytometry, eight of ten (80%) lung cancer cell lines expressed cell surface Fas. On the other hand, sFas protein and mRNA were detected in six of ten (60%) lung cancer cell lines, but there was no correlation between Fas and sFas expression. Furthermore, although the expressions of Fas and sFas were clearly detected in tumor cells derived from malignant effusion, the sFas expression was down‐regulated in an in vitro culture. These results suggest that sFas in malignant pleural effusion is at least in part produced by lung cancer cells, and might play a role in local immunosuppression by tumor cells. (Cancer Sci 2003; 94: 302–307)