SKI-178 is a selective inhibitor of sphingosine kinase 1 which is active in vitro and in vivo. SKI-178 is a competitive inhibitor of sphingosine binding to SPHK1 (Ki = 1.3 uM) and shows no inhibition of SPHK2 up to 25 uM. SKI-178 is cytotoxic to numerous cancer cell lines (MCF-7, A549, Panc-1, etc) at low to sub-micromolar concentrations.
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