JW74 antagonizes LiCl-induced activation of the canonical Wnt signaling (IC50: 420 nM).

Ki-67 expression is reduced from 97.5% in DMSO-treated cells to 86.7% in JW74-treated cells. Relative to DMSO-treated cells, the cellular viability of U2OS cells treated for 72 h treatment with 10 μM JW74 is reduced to 80%. The effect of tankyrase inhibition on cellular viability is tested by performing an MTS assay. Flow cytometry is also performed to determine the expression marker Ki-67 in U2OS following 48 h treatment with DMSO or 10 uM JW74 [2]. JW74 displays a reduction of canonical Wnt signaling in the ST-Luc assay (IC50: 790 nM) [1].

The in vivo efficacy of JW74 is tested using SW480 cell xenografts. A relatively high dose of JW74 (150 or 300 mg/kg) is used because of a rapid compound degradation in the organism as indicated in the human liver microsome analysis (t1/2=2.5 minutes) and in pharmacokinetic analyses (after peroral injections: t1/2=30 minutes and intravenous injections: t1/2=15 minutes). JW74 concentration in tumors is in the range 4.2 to 72.1 μmol/kg for JW74 150 mg/kg, 1.9 to 11.1 μmol/kg for JW74 300 mg/kg, and 2.8 μM in plasma for both doses [1].