In order to elucidate the role of inflammatory cytokines in the central nervous system, we examined the production of two leukocyte chemoattractants, IL-8 and monocyte chemotactic and activating factor (MCAF) in brain tumor cell lines. The glioma cell lines tested exhibited high levels of IL-8 and MCAF mRNA expression upon stimulation with IL-1 or TNF-alpha, while none of the neuroblastoma cell lines expressed these cytokine mRNA. Both IL-8 and MCAF mRNA expression depended on the dose of IL-1 alpha and TNF-alpha and appeared very rapidly, reaching maximal levels at 3-6 hr, with substantial production of these cytokines in the culture supernatants. When various immunosuppressive drugs were tested, glucocorticoids but not other immunosuppressive drugs markedly inhibited the IL-1 or TNF-alpha-induced IL-8 and MCAF mRNA accumulation, suggesting that glucocorticoid is a potent regulator of these inflammatory cytokine production in the neural tissues. In addition, reverse transcription-polymerase chain reaction (RT-PCR) revealed the expression of IL-8 and MCAF mRNA expression in resected brain tumor tissues including glioblastoma, astrocytoma grade 2, ependymoma and medulloblastoma, indicating that these inflammatory cytokines are expressed in vivo.