GDC0084 (RG7666) is a PI3K inhibitor with potential antineoplastic activity. GDC0084 (RG7666) specifically inhibits PI3K in the PI3K/AKT kinase (or protein kinase B) signaling pathway, thereby inhibiting the activation of the PI3K signaling pathway. This may result in the inhibition of both cell growth and survival in susceptible tumor cell populations.

PI3Kβ:46 nM(Ki app), PI3Kα:2 nM(Ki app), PI3Kδ:3 nM(Ki app), mTOR:70 nM(Ki app), PI3Kγ:10 nM(Ki app)

GDC-0084对小鼠脑中的PI3K信号通路有明显抑制效果,可抑制高达90%的pAkt信号.在U87和GS2原位移植瘤模型中,GDC-0084对肿瘤生长分别具有70%和40%的抑制作用.GDC-0084的疗效正处于临床患者检测评估阶段,暴露的耐受剂量与小鼠模型中的有效剂量一致.

在人微粒体及干细胞培养中,GDC-0084显示出良好的代谢稳定性,能抑制正常脑组织中PI3K通路的关键信号pAKT。GDC-0084抑制多种神经胶质瘤细胞的增殖（IC50：0.3-1.1 μM）。GDC-0084与血浆蛋白结合率较低,在CD-1小鼠血浆中游离分数为29.5±2.7%（n=3,5 μM）,而在CD-1小鼠中与脑组织结合率较高,游离分数只有6.7±1%(n=3)。

For transport studies, cells are seeded on 24-well Millicell plates 4 days prior to use(polyethylene terephtalate membrane, 1 μm pore size) at a seeding density of 1.3×105 cells/ml). GDC-0084 is tested at 5 μM in the apical-tobasolateral (A-B) and basolateral-to-apical (B-A) directions. The compound is dissolved in transport buffer consisting of Hanks' balanced salt solution with 10 mM HEPES. Lucifer Yellow is used as the paracellular and monolayer integrity marker. GDC-0084 concentrations in the donor and receiving compartments are determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The apparent permeability (Papp), in the apical to A-B and B-A directions, is calculated after 2-hour incubation.(Only for Reference)