Treatment of quiescent primary human fibroblasts with tumor necrosis factor (TNF) alpha, TNF-beta, interleukin-1, interferon (IFN) alpha, IFN beta, or IFN gamma induced Egr-1 mRNA. In primary human fibroblasts TNF-alpha and TNF-beta were mildly mitogenic and IFN alpha and IFN gamma were growth inhibitory. However, in HeLa cells TNF but not IFN induced the expression of Egr-1 mRNA, while both cy...