Secreted frizzled-related proteins (SFRPs) are soluble proteins that have highly restricted tissue distribution. SFRPs are capable of binding to Wnts and frizzled (Fz) receptors to interfere with Wnt signaling, which plays a major role in cell fate determination through the regulation of cell proliferation, differentiation, and apoptosis. sFRP-1 contributes to the inhibition of apoptosis in fibroblast populations. sFRP-1 proteins are involved in apoptosis by negatively modulating wingless/int (WNT) signaling by interacting with either WNTs or Frizzled receptors. By sequestering WNTs, sFRP-1 removes the stimulus for β-catenin stabilization and mediates various biological processes. SFRP proteins modulate Wnt signalling by interacting with either Wnt or frizzled receptors and are reported to affect epithelial/stromal interactions in prostate cancer.
WAY 316606 is an inhibitor of the secreted protein sFRP-1, an endogenous antagonist of the secreted glycoprotein Wnt. The affinity of WAY-316606 for sFRP-1 is determined using the FP binding assay with IC50 of 0.5 μM.