Biological Activity
SPP86 is a potent cell permeable inihbitor of RET tyrosine kinase with an IC50 value of 8 nM and with some inhibitory activity at EphA1, FGFR1, Flt4, Lck and Yes. SPP86 does not inhibit p38, CSK, KIT, PDGF, Src or BCR-ABL. SPP86 inhibited RET-mediated activation of the PI3K/Akt and MAPK pathways at doses of 0.1- 1 μM in a cell line expressing oncogenic RET and inhibited RET-induced ERα phosphorylation and proliferation in MCF7 cells with an IC50 value of 1.0 μM, similar to tamoxifen.