Ceralasertib (AZD6738) is an ATR kinase inhibitor (IC50=1 nM) with selective and oral activity. Ceralasertib has antitumor activity.

ATR:1 nM

方法: 276 种不同的肿瘤细胞系用 Ceralasertib 处理 3 天，通过 MTS assay 检测细胞活力。
结果: 对于大多数细胞系，50% 生长抑制的中位数 GI50 (1.47 µmol/L) 高于 ATR 细胞 IC90，只有 13% 的细胞系的 GI50 低于中位数，30% 低于 1 µmol/L。与实体瘤细胞 (中位数GI50=1.68 µmol/L) 相比，血液细胞系 (中位数 GI50=0.82 µmol/L) 的敏感性普遍增强。[1]
方法: 结直肠癌细胞 HT29 用 trifluridine (70 µM) 和 Ceralasertib (0.5 µM) 处理 48 h，通过 Western Blot 检测靶点蛋白表达水平。
结果: 与 trifluridine 组相比，trifluridine+Ceralasertib 组在 48 h时抑制了 HT29 细胞中的 Chk1 磷酸化。因此，证实 Ceralasertib 抑制 Chk1 磷酸化。在 HT29 和 HCT116 细胞中，trifluridine+Ceralasertib 组的 DNA 损伤比 trifluridine 组更严重，这可以通过 γH2A 表达水平的增加来证实。[2]

方法: 为检测体内抗肿瘤活性，将 Ceralasertib (10-50 mg/kg，10% DMSO+40% Propylene Glycol+50% deionized water) 口服给药给携带 LoVo、Granta-519、NCI-H23 或 549 异种移植物的 athymic nude 小鼠，每天一次，持续 14-28 天。
结果: LoVo 和 Granta-519 显示出剂量依赖性疗效，50 mg/kg 时 TGI 显著，25 mg/kg 时活性中等，10 mg/kg 时无活性。在 NCI-H23 中也观察到显著的抗肿瘤活性，但在 A549 模型中没有。[1]

General procedure for the EC50 test: DDR1 is induced by 2 Gg/ml doxycycline for 48 hrs prior to DDR1 activation by rat tail collagen I. The DDR1 over-expressed U2OS is pre-treated by media containing each concentration of the compound for 1 hr and treated by changing the media to the EC50 test media containing 10 Gg/ml collagen and each concentration of the compound for 2 hrs. Each cells is washed with cold PBS three times and lysed with the lysis buffer (50 mMTris, pH 7.5, 1% Triton X-100, 0.1% SDS, 150 mM NaCl, 5 mM EDTA, 100 mMNaF, 2 mM Na3VO4, 1 mM PMSF, 10 Gg/ml aprotinin, and 10 Gg/ml leupeptin). The activation of DDR1 is quantified by density using program ImageJ to determine EC50 following Western blot using anti-activated human DDR1b (Y513).

Cells are treated in white walled, clear bottom 96-well plates with the indicated doses of AZD6738, cisplatin, gemcitabine, or combination for 48 h. ATP levels are assessed as surrogate measure of viability was assessed using the CellTiter-Glo Luminescent Cell Viability Assay and Safire 2 plate reader. Raw data are corrected for background luminescence prior to further analysis. For AZD6738 treatment, log dose response curves are generated in GraphPad Prism 6 by nonlinear regression (log(inhibitor) vs. response with variable slope) of log-transformed (x = log(x)) data normalized to the mean of untreated controls. GI values, defined as the dose X at which Y = 50%, were extrapolated from dose response curves.