Immunoproteasomeinhibitor 1 is a highly potent and reversible inhibitor of both immunoproteasome and proteasome activity. It exhibits time-independent inhibitory effects on immunoproteasome subunits β5c, β1i, and β5i, with respective Ki values of 1.18 μM, 0.27 μM, and 1.91 μM. This compound shows promising potential for the treatment of select neoplastic diseases [1].
SNIPER(BRD)-1 is a chemical compound composed of a derivative of the IAP antagonist LCL-161 and the BET inhibitor (+)-JQ-1, linked together. It promotes the degradation of BRD4 through the ubiquitin-proteasome pathway and effectively degrades cIAP1, cIAP2, and XIAP with IC50 values of 6.8 nM, 17 nM, and 49nM, respectively[1].
C6 urea ceramide is an inhibitor of neutral ceramidase.1 It increases total ceramide levels in wild-type mouse embryonic fibroblasts (MEFs) and in HT-29 colon cancer cells but not in MEFs lacking neutral ceramidase. It inhibits proliferation of, and induces apoptosis and autophagy in HT-29, but not non-cancerous RIE-1, cells when used at concentrations of 5 and 10 μM. C6 urea ceramide decreases total β-catenin, increases phosphorylated β-catenin, and induces colocalization of β-catenin with the 20S proteasome in HT-29 and HCT116, but not RIE-1, cells. It reduces tumor growth and increases C16, C18, C20, and C24 ceramide levels in tumor tissue in an HT-29 mouse xenograft model when administered at doses of 1.25, 2.5, and 5 mg/kg for five days. |1. García-Barros, M., Coant, N., Kawamori, T., et al. Role of neutral ceramidase in colon cancer. FASEB J. 30(12), 4159-4171 (2016).
KZR-616, a first-in-class inhibitor of the immunoproteasome, selectively targets the LMP7 (IC50: 39/57 nM=hLMP7/mLMP7) and LMP2 (IC50: 131/179 nM=hLMP7/mLMP7) subunits of the immunoproteasome. KZR-616 has the potential for the research of multiple autoimmune diseases[1][2]. KZR-616 also inhibits MECL-1 subunit (IC50=623 nM) and constitutive proteasome β5 subunit (IC50=688 nM). KZR-616 maintains LMP7 and LMP2 selective inhibition in MOLT-4 cells. KZR-616 (250 nM) shows a comparable cytokine inhibition profile peripheral blood mononuclear cells (PBMC)[1].KZR-616 is an immunoproteasome-selective inhibitor identified based on the optimization of ONX-0914 and PR-924 [3]. KZR-616 (5 mg/kg; i.v.; dosing was repeated on days 6, 8, 11, and 13) shows efficacy in the anticollagen antibody induced arthritis (CAIA) model[1]. [1]. Johnson HWB, et al. Required Immunoproteasome Subunit Inhibition Profile for Anti-Inflammatory Efficacy and Clinical Candidate KZR-616 ((2 S,3 R)- N-(( S)-3-(Cyclopent-1-en-1-yl)-1-(( R)-2-methyloxiran-2-yl)-1-oxopropan-2-yl)-3-hydroxy-3-(4-methoxyphenyl)-2-(( S)-2-(2-morpholinoacetamido)propanamido)propenamide). J Med Chem. 2018 Dec 27;61(24):11127-11143. [2]. Muchamuel T, et al. FRI0296 Kzr-616, a selective inhibitor of the immunoproteasome, blocks the disease progression in multiple models of systemic lupus erythematosus (SLE). Annals of the Rheumatic Diseases 2018;77:685. [3]. Xi J, et al. Immunoproteasome-selective inhibitors: An overview of recent developments as potential drugs for hematologic malignancies and autoimmune diseases. Eur J Med Chem. 2019;182:111646.
VCP p97 inhibitor-1, a highly effective compound, inhibits VCP p97 (also known as Cdc48, CDC-48, or Ter94) with an IC 50 of 54.7 nM. This inhibitor induces a disruption in protein homeostasis and interferes with the degradation process of misfolded polypeptides by the ubiquitin-proteasome system (UPS).