Description
SB-505124 inhibits the TGF-β1 receptor serine/threonine kinase ALK5 with an IC50 value of 47 nM. Though it is a less potent antagonist of ALK4 (IC50 = 129 nM) and ALK7, SB-505124 selectively and concentration-dependently inhibits ALK4-, ALK5-, and ALK7-dependent activation of downstream SMAD2 and SMAD3 and TGF-β–induced MAP kinase pathway components without altering ALK1-3 or ALK6-induced SMAD signaling. In an assay determining in vitro phosphorylation of SMAD3, SB-505124 is more potent than SB-431452 with IC50 values of 47 versus 94 nM, respectively.
Uses
SB-505124 inhibits the TGF-β1 receptor serine/threonine kinase ALK5 with an IC50 value of 47 nM. Though it is a less potent antagonist of ALK4 (IC50 = 129 nM) and ALK7, SB-505124 selectively and concentration-dependently inhibits ALK4-, ALK5-, and ALK7-dependent activation of downstream SMAD2 and SMAD3 and TGF-β–induced MAP kinase pathway components without altering ALK1-3 or ALK6-induced SMAD signaling. In an assay determining in vitro phosphorylation of SMAD3, SB-505124 is more potent than SB-431452 with IC50 values of 47 versus 94 nM, respectively.
Uses
SB-505124 is a selective inhibitor of transforming growth factor-beta type I receptor ALK5 and as well as being a selective inhibitor of ALK4 but with less potency. SB-505124 blocks TGF-β–induced apoptosis of FaO cells and NRP 154 cells in a concentration-dependent manner. SB-505124 has been shown to suppress the migration and invasion of breast cancer MCF-7-M5 cells.
Definition
ChEBI: SB 505124 is a member of the class of imidazoles carrying tert-butyl, 1,3-benzodioxol-5-yl and 6-methylpyridin-2-yl substituents at positions 2, 4 and 5 respectively. It has a role as a TGFbeta receptor antagonist. It is a member of imidazoles, a benzodioxole and a member of methylpyridines.
Biochem/physiol Actions
SB-505124 selectively inhibits TGF-β type I receptors, activin receptor-like kinases (ALK) 4, 5 and 7. It inhibits ALK4-, 5- and 7-mediated activation of Smad2, Smad3 and MAPK pathway induced by TGF-β.1 SB-505124 inhibits the human fibroblast trans-differentiation induced by the co-culture with Esophageal squamous cell carcinoma.2
References
[1] STACEY DACOSTA BYFIELD. SB-505124 is a selective inhibitor of transforming growth factor-beta type I receptors ALK4, ALK5, and ALK7.[J]. Molecular Pharmacology, 2004, 65 3: 744-752. DOI:
10.1124/mol.65.3.744[2] JENNIFER SAPITRO. Suppression of transforming growth factor-β effects in rabbit subconjunctival fibroblasts by activin receptor-like kinase 5 inhibitor.[J]. Molecular Vision, 2010: 1880-1892.
