HhAntag

HhAntag is a specific, potent and orally active small molecule SMO antagonist of the Hh pathway^[1]. In Vitro: HhAntag (2-30 μM; 72?hours) demonstrates to be?10-times more potent than the natural product SMO antagonist, cyclopamine, at inhibiting Hh pathway activity and it inhibits Hh signalling pathway sensitivitive cells with IC₅₀ values ranging from 2?μM to >30?μM^[1].
HhAntag inhibits AsPC-1, BXPC-3, CFPAC, HPAC, HPAF-II, KP4, Panc 03.27, PA-TU-8902, PSN-1, SU.86.86 cells with IC₅₀ values of 30 μM, 5.4 μM, 5.8 μM, 2.7 μM, 6.2 μM,10.3 μM, 2.5 μM, 2.9 μM, 5.8 μM and 2.7 μM, respectively^[1].
HhAntag (100 nM) is needed to completely inhibit Hh signalling in a Hh-responsive human mesenchymal cell line (HEPM) expressing a?GLI?luciferase reporter construct (HEPM-rep), the IC₅₀?of 5?nM 400-times lower than that required to inhibit cell growth by 50% in the most sensitive cancer cell line (1.9?μM)^[1].
In Vivo: HhAntag (oral administraion; 75 mg/kg or 100 mg/kg; twice daily; 25 days) results in significant growth delay in HT55 and HT-29 colorectal cell line xenografts models, with average tumour growth inhibitions of 29% and 48%, respectively. Whereas HhAntag had no effect on the growth of DLD-1 xenografts^[1].