Dexamethasone suppresses the mucus production and muc-2 and muc-5ac
gene expression by nci-h292 cells.
Kai, Hirofumi, Kazuhisa Yoshitake, Akinori Hisatsune, Tomoyuki Kido,
Yoichiro Isohama, Kazuo Takahama, and Takeshi Miyata.
Department of Pharmacological Sciences, Faculty of Pharmaceutical
Sciences, Kumamoto University, 5-1 Oe-honmachi, Kumamoto 862,
Japan
APStracts 3:0106L, 1996.
Excessive production of airway mucus is a characteristic feature of
many chronic inflammatory lung diseases. Although current
pharmacological approaches to excessive mucus production are limited,
glucocorticoids appear to be most effective among a few useful drugs.
The exact evidence for the effectiveness of glucocorticoids on mucus
production has not been fully elucidated to date. The purpose of this
study is to clarify the effect of dexamethasone on mucus production
and mucin gene expression in a human pulmonary mucoepidermoid
carcinoma cell line (NCI-H292). NCI-H292 cells produced
hyaluronidase-resistant high-molecular weight glycoconjugates (HMWG),
which elute in the void volume on Sepharose CL-4B column
chromatography. Dexamethasone significantly suppressed the basal
production of [3H]glucosamine- or [3H]serine-labeled HMWG in NCI-H292
cells. In Northern blot analysis, dexamethasone attenuated steady
-state mRNA levels of MUC-2 and MUC-5AC mucin genes. These data
indicate that dexamethasone suppresses the basal production of HMWG
and decreases steady-state mRNA levels of mucin genes in airway
mucus-producing cancer cells.
Received 5 February 1996; accepted in final form 11 June 1996.
APS Manuscript Number L38-6.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 4 July 96