YO-01027 (DBZ) is a potent γ-secretase inhibitor.

γ-secretase (Notch):2.9 nM, γ-secretase (APPL):2.6 nM

YO-01027直接作用于γ-分泌酶复合体，针对N端的Preseenilin片段。随着YO-01027浓度的增加，对APPL-或Notch表达细胞进行处理会导致APPL CTF片段的逐步积累以及NICD产量的降低，且这种作用完全依赖于剂量。[1] 10 μM的YO-01027能够减少乳腺癌干细胞(BCSC)的数量和活性。[2] 最近的研究表明，YO-01027在未分化细胞中通过Notch抑制作用，以浓度依赖的方式，在未达到密集和密集阶段均能损害粘液蛋白MUC16的生物合成，但在后分裂成层细胞中则不会。[3]

YO-01027通过每隔3天一次的腹腔注射，剂量为1 mg/mL，在细胞注射当日及之后给药，显著降低MCF7肿瘤的生成，而对MDA-MB-231肿瘤无显著影响。形成的YO-01027处理过的MCF7肿瘤体积显著减小。[2] 在C57BL/6小鼠中，YO-01027的治疗能够依赖剂量抑制上皮细胞增殖，并在肠腺瘤中诱导杯状细胞分化。[4]

Pharmacological Inhibition of γ-secretase Activity: For YO-01027, pilot experiments are performed with different drug concentrations ranging from 0.1 nM to 250 nM to determine the effective linear range and maximal inhibition dose for YO-01027. YO-01027 is added at the required concentrations to the S2 cell medium upon induction of Notch or APPL expression, 6 hours before protein harvesting. For each sample, YO-01027 is also included at the corresponding concentration in the lysis buffer for protein extraction and immunoblot analysis.

Cells are resuspended at ≤1 × 106 in 100 μL sorting buffer (PBS containing 0.5% bovine serum albumin, 2 mM EDTA) and incubated with preconjugated primary antibodies BEREP4-FITC (1:10), CD44-APC (1:20), and CD24-PE (1:10) for 10 minutes at 4 °C. The cells are washed in PBS and centrifuged at 800 × g for 2 minutes. For analysis, cells are resuspended in 500 μL of sorting buffer and fluorescence is measured using FACSCalibur and analyzed using WinMIDI 2.8. For sorting, cells are resuspended in 1× HBSS after incubation with the primary antibodies. Cells are sorted, with HBSS as sheath fluid, at 16 p.s.i. using FACSAria. The CD24low cell population gated by FACS is the lowest quintile of CD24-positive cells plus all the CD24-negative cells.(Only for Reference)