The SAR for this series is summarized in Figure 4.

Ovatodiolide promoted catenin degradation through the 26S Bosutinib proteosome pathway but not lysosome associated protein degradation pathway. The interaction between E cadherin, catenin, TCF4, and catenin was further compared by coimmunoprecipitation. TCF4 catenin interaction but not E cadherin catenin interaction was remarkably reduced in each cell. Despite the Caki 1, 786 O, and A498 being socalled E cadherin negative cells, the faintly immunoprecipitated E cadherins were unchanged after ovatodiolide treatment. Catenins phosphorylated by GSK3at residues T41, S37, and S33 are recognized by the TrCP E3 ubiquitin ligase complex, ubiquitinylated, and ultimately degraded by the 26S proteosome. GSK3phosphorylated by active AKT inhibits GSK3kinase activity. Otherwise, catenin phosphorylated at S552 by active AKT enhances catenin protein levels and nuclear signaling. We addressed these possible regulators and catenin Papillary thyroid cancer phosphorylation status with ovatodiolide treatment. Ovatodiolide dose and time dependently reduced both phosphorylated AKT and GSK3levels. Therefore, phosphorylated catenin S552 forms were decreased but phosphorylated S33/37/T41 forms were increased. Treatment with the AKT inhibitor VIII induced similar effects, and constitutively active AKT abrogated the ovatodiolide induced inhibition of catenin signaling. The effect of constitutively active Akt also partially rescued the OVA induced cell death. Besides, ovatodiolide treatment did not modify other downstream molecules of AKT, including p Foxo3a, p mTOR, and p p70S6K levels. Therefore, ovatodiolide Cilengitide inhibited catenin signaling by reducing catenin activity and stability. With ovatodiolide treatment of xenografted mice, levels of phosphorylated catenin, cell cycle markers Ki 67 and cyclin D1, and survival marker survivin were decreased as compared with controls and 4 and levels of phosphorylated AKT and GSK3were decreased. Thus, ovatodiolide reduced catenin signaling in vivo and reduced RCC cell tumorigenicity. The physical binding between ovatodiolide and catenin was simulated on the molecular docking website PATCH DOCK with the 3D structure files for ovatodiolide and catenin. As in Figure S6B, the ovatodiolide inserted into the catenin molecule enclosing by the AKT phosphorylation site, Ser 552 residue, and may result in a stereochemical change to reduce its activation. However, there is no proper 3D structure including N terminus of catenin and it is uneasy to evaluate whether ovatodiolide also bound to theGSK3targeting Ser33, Ser37, orThr41 residues. We cultured sorafenib resistant or sunitinib resistant 786 O and ACHN cell lines to determine whether ovatodiolide could resensitize drug resistant cells towards these chemotherapeutic agents. On treatment with 5 ??M sorafenib or sunitinib for 48 hr, all drug resistant 786 O and ACHN cells showed at least 2.