Dexamethasone inhibits invasion of murine T cells through cultured fibroblastic monolayers

Despite the wide clinical use of glucocorticoids in the chemotherapy of leu kaemia and lymphoma. there have been limited efforts at understanding the e ffects of these hormones on metastasis formation. The purpose of this study was to investigate the effects of glucocorticoids on the tissue-infiltrati ng capability of lymphoid cells. Using an in vitro invasion assay, we found that dexamethasone, a synthetic glucocorticoid analogue, inhibited the inv asion of a murine T-cell hybridoma through a monolayer of fibroblast-like c ells. Even low doses of dexamethasone were effective at inhibiting cellular transmigration (EC50 = 0.4 nM). A maximal decrease was observed after an o vernight culture in the presence of dexamethasone. The effect persisted for at least 24 h after removal of the drug and required the binding of the ho rmone to its intracellular glucocorticoid receptor. Our results suggest tha t the decreased invasiveness of dexamethasone-treated cells is not the cons equence of reduced motility or deficient production of an autocrine factor required for cell migration. This in vitro study suggests that glucocortico ids may act to reduce dissemination of lymphoma cells in vivo. (C) 2001 Els evier Science B.V. All rights reserved.