RESUMEN
The identification of a new series of RORc inverse agonists is described. Comprehensive structure-activity relationship studies of this reversed sulfonamide series identified potent RORc inverse agonists in biochemical and cellular assays which were also selective against a panel of nuclear receptors. Our work has contributed a compound that may serve as a useful in vitro tool to delineate the complex biological pathways involved in signalling through RORc. An X-ray co-crystal structure of an analogue with RORc has also provided useful insights into the binding interactions of the new series.
Asunto(s)
Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/agonistas , Sulfonamidas/química , Sitios de Unión , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Citocinas/biosíntesis , Agonismo Inverso de Drogas , Células HEK293 , Humanos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/efectos de los fármacos , Simulación de Dinámica Molecular , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/antagonistas & inhibidores , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/toxicidadRESUMEN
The authors describe the use of modified baculoviruses containing mammalian expression cassettes (BacMam technology) in steroid nuclear receptor reporter assays designed for screening and profiling agonist and antagonist compounds. Baculo-viruses were constructed that express full-length human genes for mineralocorticoid receptor (MR), glucocorticoid receptor (GR), progesterone receptor A (PR-A), and progesterone receptor B (PR-B) from the cytomegalovirus immediate early promoter. A virus carrying the mouse mammary tumor virus-firefly luciferase (MMTV-Luc) cassette was generated to provide a suitable reporter construct. Feasibility studies with BacMam-MR in single-dose tests of 1000 compounds showed high correlation to the standard transfection-based assay results. Likewise, in dose-response experiments, BacMam-based assays for GR and PR-B produced potency and efficacy values similar to transfection assay results. At various receptor/reporter ratios, the BacMam assays showed good flexibility, demonstrating consistent signal-to-background (S/B) ratios and compound potencies. Increasing transduction time from 24 to 48 h provided no benefit, actually reducing overall assay performance as measured by S/B and Z' values. The BacMam technology was applied in studies of isoforms PR-A and PR-B, which showed similar responses to a series of agonists. Taken together, the results demonstrate the utility of steroid nuclear receptor BacMam constructs for compound screening procedures with high reproducibility, reduced turnaround time, and lower cost.