Wnt3-frizzled 1 chimera as a model to study canonical Wnt signaling.

Wnt proteins initiate signaling by binding to seven transmembrane spanning receptors of the frizzled (Fz) family together with the members of the low-density lipoprotein receptor-related protein (LRP) 5 and 6. A chimera of human Wnt3 and Fz1 receptor was developed that efficiently activated the TCF-luciferase reporter. Deletion of the cytoplasmic tail and point mutations in the PDZ binding region in the chimera resulted in the loss of Wnt signaling, suggesting a critical role for the Fz cytoplasmic region in Wnt signaling.

Identification of iminooxothiazolidines as secreted frizzled related protein-1 inhibitors.

Secreted frizzled related protein-1 (sFRP-1) inhibitors have the potential to be used for the treatment of osteoporosis or other bone related disorders, since the level of sFRP-1 affects osteoblast apoptosis and proliferation. From high throughput screening, we have identified a class of iminooxothiazolidines as sFRP-1 inhibitors. Structure-activity relationships were established for various regions of the scaffold along with the biochemical characterization of this class to probe selectivity, binding and ex vivo activity.

A small molecule inhibitor of the Wnt antagonist secreted frizzled-related protein-1 stimulates bone formation.

Canonical Wnt signaling has been demonstrated to increase bone formation, and Wnt pathway components are being pursued as potential drug targets for osteoporosis and other metabolic bone diseases. Deletion of the Wnt antagonist secreted frizzled-related protein (sFRP)-1 in mice activates canonical signaling in bone and increases trabecular bone formation in aged animals. We have developed small molecules that bind to and inhibit sFRP-1 in vitro and demonstrate robust anabolic activity in an ex vivo organ culture assay.

Identification of diarylsulfone sulfonamides as secreted frizzled related protein-1 (sFRP-1) inhibitors.

Inhibitor of secreted frizzled related protein-1 (sFRP-1) would be a novel potential osteogenic agent, since loss of sFRP-1 affects osteoblast proliferation, differentiation, and activity, resulting in improved bone mineral density, quality, and strength. We have identified small molecule diarylsulfone sulfonamide derivatives as sFRP-1 inhibitors. Structure-activity relationship generated for various regions of the scaffold was utilized to improve the biochemical profile, resulting in the identification of potent selective analogues, such as 16 with desirable pharmaceutical profile.

[Attainment of generic therapy goals in a specialized group psychotherapy for phobic outpatients].

Individual therapy goals of psychotherapy patients either focus on symptom relief (disorder specific) or on improvements also in other functional areas (generic). The present study with 62 outpatients in a cognitive behavioral group psychotherapy (CBGT) investigated whether patients attain their disorder specific goals better than their generic therapy goals. Results indicated that patients reached disorder specific goals to a higher degree than the generic goals, although the group treatment specifically targeted the disorder specific goals.

Structure-function analysis of secreted frizzled-related protein-1 for its Wnt antagonist function.

Secreted frizzled-related proteins (sFRPs) are glycoproteins that are recognized as Wnt antagonists. To identify the functional domains that are involved in Wnt antagonist function, several sFRP-1 mutants and sFRP-1/sFRP-2 chimeras were generated. These mutants were characterized in an optimized T-cell factor (TCF)-luciferase based assay in U2OS human osteosarcoma cells.

The Wnt antagonist secreted frizzled-related protein-1 controls osteoblast and osteocyte apoptosis.

Mechanisms controlling human bone formation remain to be fully elucidated. We have used differential display-polymerase chain reaction analysis to characterize osteogenic pathways in conditionally immortalized human osteoblasts (HOBs) representing distinct stages of differentiation. We identified 82 differentially expressed messages and found that the Wnt antagonist secreted frizzled-related protein (sFRP)-1 was the most highly regulated of these.

Regulated expression of sFRP-1 protein by the GeneSwitch system.

The GeneSwitch system is a mifepristone-inducible expression system that provides exceptionally low uninduced and high-induced protein expression in mammalian cells. We have developed an adenovirus recombinant containing GeneSwitch protein driven by the GAL4-tk promoter, as well as recombinants containing sFRP-1 and luciferase reporter under the control of the GAL4-E1b promoter. Luciferase activity in A549 cells infected with the GeneSwitch and Luciferase viruses is very low in ethanol-treated cells, while the level of luciferase activity increases 200-fold in cells treated with mifepristone.

Molecular determinants of ER alpha and ER beta involved in selectivity of 16 alpha-iodo-7 beta estradiol.

The two known estrogen receptors, ER alpha and ER beta, are hormone inducible transcription factors that have distinct roles in regulating cell proliferation and differentiation. The natural ligand, 17 beta-estradiol (E2), binds with high affinity to both ER alpha and ER beta. However, a close analogue, 16 alpha-iodo-17 beta-estradiol (16 alpha IE2) showed about 10-fold selectivity for ER alpha over ER beta.