tcsc0135 SB-431542

SB-431542 is a potent and selective inhibitor of ALK5 with an IC₅₀ value of 94 nM, and is also an inhibitor of TGF-β Receptor.

IC50 & Target: IC50: 94 nM (ALK5)^[2]

In Vitro: SB-431542 (1 μM) significantly reduces the TGF-β-induced nuclear accumulation of Smad proteins in A498 cells. SB-431542 inhibits TGF-β1-induced collagen Iα1 and PAI-1 mRNA with IC₅₀ values of 60 and 50 nM, respectively. In addition, SB-431542 inhibits TGF-β1-induced fibronectin mRNA and protein with IC₅₀ values of 62 and 22 nM, respectively^[1]. SB-431542 (10 μM) is a selective inhibitor of endogenous activin and TGF-β signaling but has no effect on BMP signaling in NIH 3T3 cells^[2]. TRKI, SB-431542, inhibits TGF-beta-induced transcription, gene expression, apoptosis, and growth suppression. SB-431542 attenuates the tumor-promoting effects of TGF-beta, including TGF-beta-induced EMT, cell motility, migration and invasion, and vascular endothelial growth factor secretion in human cancer cell lines. SB-431542 induces anchorage independent growth of cells that are growth-inhibited by TGF-beta, whereas it reduces colony formation by cells that are growth-promoted by TGF-beta^[3]. SB-431542 (0.3 μM) inhibits cell proliferation induced by TGF-β in MG63 cells^[4].

In Vivo: SB-431542 (10 mg/kg, i.p.) decreases lung metastasis but does not significantly alter growth of the primary tumor 4T1 xenograft^[5].