Conformational Switch of Benzanilide Derivative Induced by Acid; Effect of Pentafluorobenzoyl Group.

Amide-based molecular switches had its limitation on structural diversities. In this work, we designed and synthesized a series of pentafluorobenzoyl-based benzanilide compounds. The conformational ratio of these compounds in solution was correlated linearly with Hammett's σp value of the substituent on the anilide ring, reflecting the repulsive interaction between the carbonyl group and the electron-rich aryl group. The addition of acid into the solution of 6, bearing pentafluorobenzoyl group, switched the stable amide conformation. In addition, the sizeable rotational barrier of 6 induced by the pentafluorobenzoyl moiety enabled us to monitor the conformational transition by means of 1H NMR spectroscopy.

Eomesodermin promotes interaction of RelA and NFATc2 with the Ifng promoter and multiple conserved noncoding sequences across the Ifng locus in mouse lymphoma BW5147 cells.

The T-box transcription factor Eomesodermin (Eomes) regulates the lineage-dependent expression of interferon γ (IFN-γ). We previously showed that Eomes promotes IFN-γ production and interacts with multiple conserved noncoding sequences (CNS) across the Ifng locus in mouse lymphoma BW5147 cells. In the present study, we investigated the transcriptional regulation of IFN-γ by the nuclear factor κB (NF-κB) subunit RelA and nuclear factor of activated T cells c2 (NFATc2, also known as NFAT1) in Eomes-transfected BW5147 cells. Eomes promoted the interaction of RelA and NFATc2 with the Ifng promoter and five CNS, including CNS-22 and CNS+30 upon stimulation with phorbol 12-myristate 13-acetate (PMA) and ionomycin (IM). The dual NF-κB and STAT3 inhibitor TPCA-1 moderately reduced the PMA- and IM-induced IFN-γ transcription in Eomes-transfected BW5147 cells. TPCA-1 interfered with RelA binding to the Ifng promoter, CNS-22 and CNS+30. Moreover, TPCA-1 reduced the interaction of Eomes or NFATc2 with the Ifng promoter and CNS+30. The present results indicate that Eomes promotes the interaction of RelA and NFATc2 with the Ifng promoter and multiple CNS across the Ifng locus in BW5147 cells.

Quinacrine Inhibits ICAM-1 Transcription by Blocking DNA Binding of the NF-κB Subunit p65 and Sensitizes Human Lung Adenocarcinoma A549 Cells to TNF-α and the Fas Ligand.

Quinacrine has been used for therapeutic drugs in some clinical settings. In the present study, we demonstrated that quinacrine decreased the expression of intercellular adhesion molecule-1 (ICAM-1) induced by tumor necrosis factor (TNF)-α and interleukin-1 (IL-1) α in human lung adenocarcinoma A549 cells. Quinacrine inhibited ICAM-1 mRNA expression and nuclear factor κB (NF-κB)-responsive luciferase reporter activity following a treatment with TNF-α and IL-1α. In the NF-κB signaling pathway, quinacrine did not markedly affect the TNF-α-induced degradation of the inhibitor of NF-κB or the TNF-α-induced phosphorylation of the NF-κB subunit, p65, at Ser-536 and its subsequent translocation to the nucleus. In contrast, a chromatin immunoprecipitation assay showed that quinacrine prevented the binding of p65 to the ICAM-1 promoter following TNF-α stimulation. Moreover, TNF-α and the Fas ligand effectively reduced the viability of A549 cells in the presence of quinacrine only. Quinacrine down-regulated the constitutive and TNF-α-induced expression of c-FLIP and Mcl-1 in A549 cells. These results revealed that quinacrine inhibits ICAM-1 transcription by blocking the DNA binding of p65 and sensitizes A549 cells to TNF-α and the Fas ligand.

Eomesodermin promotes interferon-γ expression and binds to multiple conserved noncoding sequences across the Ifng locus in mouse thymoma cell lines.

The T-box transcription factors T-bet and eomesodermin (Eomes) have been shown to regulate the lineage-specific expression of interferon-γ (IFN-γ). However, in contrast to T-bet, the role of Eomes in the expression of IFN-γ remains unclear. In this study, we investigated the Eomes-dependent expression of IFN-γ in the mouse thymoma BW5147 and EL4 cells, which do not express T-bet or Eomes. The ectopic expression of Eomes induced BW5147 and EL4 cells to produce IFN-γ in response to phorbol 12-myristate 13-acetate (PMA) and ionomycin (IM). In BW5147 cells, Eomes augmented luciferase activity driven by the Ifng promoter encoding from -2500 to +113 bp; however, it was not increased by a stimulation with PMA and IM. A chromatin immunoprecipitation assay showed that Eomes bound to the Ifng promoter and conserved noncoding sequence (CNS) -22 kb across the Ifng locus with high efficacy in BW5147 cells. Moreover, Eomes increased permissive histone modifications in the Ifng promoter and multiple CNSs. The stimulation with PMA and IM greatly augmented Eomes binding to CNS-54, CNS-34, CNS+19 and CNS+30, which was inhibited by FK506. These results indicated that Eomes bound to the Ifng promoter and multiple CNSs in stimulation-dependent and stimulation-independent manners.