N-substituted benzamides inhibit nuclear factor-kappa B and nuclear factorof activated T cells activity while inducing activator protein 1 activity in T lymphocytes

N-substituted benzamides are compounds that have recently been reported to inhibit nuclear factor-kappaB (NF-kappaB) activity and induce apoptosis in a pre-B cell line. In this study. we focused on the effects of N-substitute d benzamides on transcriptional regulation in Jurkat T cells. We used a mod el system where the cells can be stimulated either through TCR/CD28 or by t reatment of the cells with PMA and ionomycin to induce transcription factor s typical for T lymphocyte activation. Treatment of the Jurkat cells with p rocainamide did not influence the transcription factor profile of stimulate d cells, while treatment with a derivative having an acetyl group in positi on 4 of the aromatic ring inhibited NF-kappaB and nuclear factor of activat ed T cells (NFAT) activity. Declopramide, which contains a chloride in posi tion 3 of the aromatic ring, was inactive in this system, whereas also the acetylated derivative of this compound inhibited NF-kappaB and NFAT activit y. In contrast, the transcriptional activity and nuclear expression of acti vator protein I induced by TCR/CD28 stimulation or PMA and ionomycin treatm ent was enhanced by the acetylated variants of the N-substituted benzamides . Finally, we investigated the effect of N-substituted benzamides on intact promoters for two genes central in immune regulation; the CD40 ligand (CD4 0L) and IL-2 promoters. The transcriptional activity of the CD40L promoter as well as surface expression of the CD40L induced by signaling through TCR /CD28 was inhibited by addition of acetylated N-substituted benzamides, whi le the transcriptional activity of the IL-2 promoter was enhanced. Taken to gether, these data indicate that derivatives of N-substituted benzamides ar e potential drug candidates for quantitative as well as qualitative modulat ion of immune functions. (C) 2001 Elsevier Science Ltd. All rights reserved .