UK-101 is a potent and selective immunoproteasome β1i (LMP2) inhibitor with an IC 50 value of 104 nM, displays 144- and 10-fold selectivity over β1c ( IC 50 =15 μM) and β5 subunit ( IC 50 =1 μM), respectivey UK-101 induces cell apoptosis and can be used for the study of prostate cancer . In Vitro UK-101 (2-8 μM; 24 hours) induces cell cycle arrest and increases the number of the PC-3 cells arrest in G1 phase of the cell cycle. UK-101 (2-8 μM; 24 hours) induces cell apoptosis, shows a minimal increase in late apoptosis, but has no significant increase in early apoptosis. UK-101 (1-8 μM; 24 hours) induces cells accumulation in the G1 phase of the cell cycle, it increases p27 accumulation and significantly increases PARP cleavage as a dose-dependent manner. MCE has not independently confirmed the accuracy of these methods. They are for reference only. Cell Cycle AnalysisCell Line: PC-3 cells Concentration: 2 μM; 8 μM Incubation Time: 24 hours Result: Induced G1 cell cycle arrest in PC-3 cells. Apoptosis AnalysisCell Line: PC-3 cells Concentration: 2 μM; 8 μM Incubation Time: 24 hours Result: Increased cell apoptosis as a dose-dependent manner. Western Blot AnalysisCell Line: PC-3 cells Concentration: 1 μM; 2 μM; 8 μM Incubation Time: 24 hours Result: Increased PARP cleavage and p27 accumulation as a dose-dependent manner. In Vivo UK-101 (intraperitoneal injection; 1-3 mg/kg; twice a week; 3 weeks) decreases tumor volume as a dose-dependent manner, it significantly decreases tumor volume at a dose of 3 mg/kg. Additionally, UK-101-treated mice is suffering less systemic toxicity and the weights of mice treated with UK-101 remains steady over the 3-week treatment period. MCE has not independently confirmed the accuracy of these methods. They are for reference only. Animal Model: Subcutaneously implanted PC-3 cells in 6-week-old male BALB/c athymic nude miceDosage: 1 mg/kg; 3 mg/kg Administration: Intraperitoneal injection; twice a week; 3 weeks Result: Inhibited tumour growth in the prostate cancer mouse xenograft model. IC50& Target:IC50: 104 nM (LMP2) IC50: 15 μM (immunoproteasome β1c) IC50: 1 μM (immunoproteasome β5)