To explore the mechanism underlying glucocorticoids' inhibition of EGF signaling, we tested the effect of glucocorticoids on the expression of HB-EGF, an EGFR ligand that is known to be de novo induced in patients with RPGN but not non crescentic glomerulonephritis (18). The gene discussed is EGFR; the disease is rapidly progressive glomerulonephritis.