Human astrocytes, human astrocytoma U373-MG and human hepatoma HepG2 cells were treated with IL-1α (10 ng/ml), OSM (25 ng/ml), or 1 μM dexamethasone (DEX) as indicated. RNA was isolated after 18 hours (left panel) or at indicated times (right panel, IL-1 and DEX treatment), and subjected to Northern blot analysis using ACT cDNA as a probe. The bottom panels show 28S rRNA stained with ethidium bromide on the membrane. Numbers correspond to fold-induction.