SD-208 (ALK5 Inhibitor V), a selective TGF-βRI (ALK5) inhibitor (IC50: 48 nM), is >100-fold selectivity over TGF-βRII.

TGFβRI:48 nM

SD-208（1 mg/mL,p.o.）使负荷SMA-560胶质瘤小鼠的中值存活率显著延长.在同源129S1小鼠体内,SD-208（60 mg/kg,p.o.）抑制初级R3T肿瘤生长,并使肺转移的数量及大小减少.在小鼠大动脉同种移植模型中,SD-208可有效减少移植动脉硬化内膜增生的形成.

在体外,SD-208阻断TGF-β诱导的受体相关Smads,Smad/3磷酸化,且对上皮细胞到间叶细胞的分化转化、迁移及侵袭到基底膜具有刺激作用。在体外,SD-208还可阻断TGF-β对新生内膜平滑肌样细胞迁移与增殖的保护作用。在小鼠SMA-560和人SMA-560胶质瘤细胞中,SD-208抑制细胞生长、组成及转化生长因子-β诱发的迁移和浸润,并使免疫原性增强。

Kinase assay: Various kinase activities are assayed by measuring the incorporation of radiolabeled ATP into a peptide or protein substrate. The reactions are performed in 96-well plates and included the relevant kinase, substrate, ATP, and appropriate cofactors. The reactions are incubated and then stopped by the addition of phosphoric acid. Substrate is captured onto a phosphocellulose filter, which is washed free of unreacted ATP. The counts incorporated are determined by counting on a microplate scintillation counter. The ability of SD-208 to inhibit the respective kinase is determined by comparing counts incorporated in the presence of compound with those incorporated in the absence of compound.

Glioma cells are cultured in the absence or presence of SD-208 (1 μM) for 48 hours. The cells are pulsed for the last 24 hours with [methyl-3H]thymidine (0.5 μCi) and harvested, and incorporated radioactivity is determined in a liquid scintillation counter.(Only for Reference)