Published ahead of print on September 15, 2005, doi:10.1165/rcmb.2005-0194OC
© 2006 American Thoracic Society DOI: 10.1165/rcmb.2005-0194OC Proliferative Stimulus of Lung Fibroblasts on Lung Cancer Cells Is Impaired by the Receptor for Advanced Glycation End-ProductsClinic of Cardio-Thoracic Surgery, Martin Luther University Halle-Wittenberg, Halle/Saale; and Institute of Immunology, Technical University Dresden, Dresden, Germany Correspondence and requests for reprints should be addressed to Dr. Babett Bartling, Klinik für Herz- und Thoraxchirurgie, Martin-Luther-Universität Halle-Wittenberg, Ernst-Grube-Str. 40, D-06120 Halle/Saale, Germany. E-mail: babett.bartling{at}medizin.uni-halle.de The receptor for advanced glycation end-products (RAGE) is highly expressed in lung tissue, especially at the site of the alveolar epithelium, but its expression is reduced in lung carcinomas. Because epithelial–mesenchymal interactions are suggested to contribute to cancer progression, we investigated the RAGE-dependent impact of fibroblasts on tumor cell growth. Cocultivation of human lung cancer cells (H358) with lung fibroblasts (WI-38) improved their proliferation in monolayer and spheroid culture models, the number of H358 cells in the S/G2 cell cycle phase increased, and there was less spontaneous cell death. Overexpression of full-length human RAGE reduced the proliferative stimulus of fibroblasts as seen in monolayers (cell number, cell cycle), spheroid cultures (spheroid size), and in a colony-forming assay compared with mock-transfected cells. Comparable results were observed by culturing H358 cells with and without RAGE overexpression in the presence of conditioned medium taken from WI-38 cells, or in response to selected growth factors, such as basic fibroblast growth factor. Moreover, we clearly showed that the fibroblast-induced proliferation correlates with activation of the p42/44 mitogen-activated protein kinase, but not with Akt kinase activation. On the basis of lung cancer as an age-related disease, we additionally proved the impact of senescent WI-38 fibroblasts. Here, we show that senescent fibroblasts improve H358 cell proliferation to the same extent as do presenescent fibroblasts. From our data, we conclude that re-expression of RAGE in lung cancer cells impairs the proliferative stimulus mediated by fibroblasts. Therefore, lung cancer progression may be enhanced by the RAGE downregulation in human lung carcinomas.
Key Words: coculture • fibroblast • lung cancer • receptor for advanced glycation end-products • senescence This article has been cited by other articles:
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