UM-164 (DAS-DFGO-II), a highly potent c-Src inhibitor with a dissociation constant (Kd) of 2.7 nM, also effectively inhibits p38α and p38β.

c-Src:2.7 nM

UM-164 是一种高效的c-Src抑制剂，其结合常数与Dasatinib相当（UM-164 Kd=2.7 nM，Dasatinib Kd=0.7 nM），在生化实验中得以证实。为验证UM-164能够在体外抑制c-Src的活化，研究了UM-164对两种TNBC细胞系（MDA-MB 231 和 SUM 149）中c-Src自磷酸化作用的影响。观察到c-Src自磷酸化的抑制依赖于浓度和时间。在120分钟时，50 nM的UM-164能完全抑制c-Src自磷酸化，证明UM-164是一种在体外强效的c-Src抑制剂。流式细胞术实验显示，UM-164处理MDA-MB 231和SUM 149后，G0-G1期细胞的比例分别增加了25%和28%，同时S期细胞的比例分别减少了16%和19%[1]。

在使用NCr裸鼠植入MDA-MB 231和SUM 149细胞株进行异种移植研究后，当肿瘤变得可触摸时，将小鼠随机分为对照组和治疗组。随后，这些小鼠通过腹腔注射方式接受化合物（在所有异种移植研究中，剂量为10和20 mg/kg；在SUM 149异种移植研究中还增加了15 mg/kg剂量）或载体的治疗，每两天一次（每组5只小鼠）。选定剂量的UM-164治疗后，即使经过52天的治疗，也没有在受治疗动物中观察到显著的体重减轻或明显畸形。然而，与接受载体治疗的组相比，10 mg/kg和20 mg/kg剂量组的肿瘤生长显著受到抑制（分别是P<0.026和P<0.004）[1]。

MDA-MB 231 and SUM 149 cells are plated in triplicate on 60 mm dishes at a density of 1×106 cells/flask. After 24 h, a final concentration of 1 μM UM-164 is added to the cells and incubated for 24 h. Growth medium is then removed and cells are washed with PBS. The remaining cells are trypsinized, harvested, and placed together with growth medium and PBS. Cells are pelleted and re-suspended in 3 mL of 75% ethanol, followed by overnight storage at - 20°C. After incubation, cells are centrifuged at 1,500 rpm for 5 min and the cell pellets are re-suspended in 0.05 mg/mL propidium iodide (10 μg/mL) containing 300 μg/mL RNase. Cell clumps are filtered. Cell DNA content is measured on flow cytometer and cell cycle distribution is calculated from 10,000 cells using FACS analysis[1] .

Mice[1]