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bioRxiv · 10.1101/2021.02.19.431952

Small molecule allosteric inhibitors of RORγt block Th17-dependent inflammation and associated gene expression in vivo.

Abstract

Retinoic acid receptor-related orphan nuclear receptor (ROR) {gamma}t is a member of the RORC nuclear hormone receptor family of transcription factors. ROR{gamma}t functions as a critical regulator of thymopoiesis and immune responses. ROR{gamma}t is expressed in multiple immune cell populations including Th17 cells, where its primary function is regulation of immune responses to bacteria and fungi through IL-17A production. However, excessive IL-17A production has been linked to numerous autoimmune diseases. Moreover, Th17 cells have been shown to elicit both pro- and anti-tumor effects. Thus, modulation of the ROR{gamma}t/IL-17A axis may represent an attractive therapeutic target for the treatment of autoimmune disorders and some cancers. Herein we report the design, synthesis and characterization of three selective allosteric ROR{gamma}t inhibitors in preclinical models of inflammation and tumor growth. We demonstrate that these compounds can inhibit Th17 differentiation and maintenance in vitro and Th17-dependent inflammation and associated gene expression in vivo, in a dose-dependent manner. Finally, ROR{gamma}t inhibitors were shown to inhibit tumor formation in pancreatic ductal adenocarcinoma (PDAC) organoids.

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BibTeXRIS

Saenz, S. A., Local, A., Carr, T., Shakya, A., Koul, S., Hu, H., Chourb, L., Stedman, J., Malley, J., DAgostino, L. A., Shanmugasundaram, V., Malona, J., Schwartz, C. E., Beebe, L., Clements, M., Rajaraman, G., Cho, J., Jiang, L., Dubrovskiy, A., Kreilein, M., Shimanovich, R., Hamann, L. G., Escoubet, L., Ellis, J. M.. 2021-02-19. Small molecule allosteric inhibitors of RORγt block Th17-dependent inflammation and associated gene expression in vivo.. https://doi.org/10.1101/2021.02.19.431952

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