Cucurbitacin B

• CAS: 6199-67-3
• Catalog Number: ACM6199673
• Category: Inhibitors
• Molecular Weight: 558.70
• Molecular Formula: C32H46O8
• Description: Cucurbitacin B belongs to a class of highly oxidized tetracyclic triterpenoids and can repress cancer cell progression. Its IC50 value is indicative of its anticancer potential. In vitro, Cucurbitacin B inhibited growth and modulated the expression of cell-cycle regulators in SHSY5Y cells. At the molecular level, Cucurbitacin B suppressed AKT signaling activation through up-regulation of PTEN. Additionally, Cucurbitacin B induced apoptosis of lung cancer cells in a concentration-dependent manner, as determined by fluorescence microscopy, flow cytometry, and transmission electron microscopy. It also inhibited lung cancer cell proliferation in a dose-dependent manner, accompanied by cell cycle inhibition and downregulation of cyclin B1. Apoptosis induced by Cucurbitacin B was associated with cytochrome c release, B-cell lymphoma 2 downregulation, and inhibition of the STAT3 pathway. Cucurbitacin B inhibited the expression of integrin α6 (ITGA6) and integrin β4 (ITGB4), which are overexpressed in certain cancer types, while inducing the expression of integrin β1 (ITGB1) and integrin β3 (ITGB3), known to mediate integrin-related cell death. Treatment with Cucurbitacin B also caused DNA double-strand breaks (DSBs) without affecting STAT3, a potential molecular target for the compound. Cucurbitacin B triggered ATM-activated Chk1-Cdc25C-Cdk1 pathways, which could be reversed by both ATM siRNA and Chk1 siRNA. Furthermore, Cucurbitacin B activated ATM-initiated p53-14-3-3-σ pathways, also reversible by ATM siRNA.; In vivo, the efficacy of Cucurbitacin B was tested using two different orthotopic models of cancer. Cells were injected orthotopically into the mammary fat pad of female athymic nude mice or BALB/c mice, respectively. Results demonstrated that Cucurbitacin B administration inhibited tumor growth by 55% in one model and 40% in another. The second model represents advanced-stage cancer with highly aggressive tumor growth.
• IUPAC Name: [(E,6R)-6-[(2S,8S,9R,10R,13R,14S,16R,17R)-2,16-dihydroxy-4,4,9,13,14-pentamethyl-3,11-dioxo-2,7,8,10,12,15,16,17-octahydro-1H-cyclopenta[a]phenanthren-17-yl]-6-hydroxy-2-methyl-5-oxohept-3-en-2-yl] acetate
• SMILES: CC(=O)OC(C)(C)C=CC(=O)C(C)(C1C(CC2(C1(CC(=O)C3(C2CC=C4C3CC(C(=O)C4(C)C)O)C)C)C)O)O
• InChI: InChI=1S/C32H46O8/c1-17(33)40-27(2,3)13-12-23(36)32(9,39)25-21(35)15-29(6)22-11-10-18-19(14-20(34)26(38)28(18,4)5)31(22,8)24(37)16-30(25,29)7/h10,12-13,19-22,25,34-35,39H,11,14-16H2,1-9H3/b13-12+/t19-,20+,21-,22+,25+,29+,30-,31+,32+/m1/s1
• InChI Key: IXQKXEUSCPEQRD-DKRGWESNSA-N
• Appearance: White powder
• Storage: Powder-20°C, 3 years; 4°C, 2 years; In solvent-80°C, 6 months; -20°C, 1 month.
• Shipping: Can be shipped at room temperature, where not in use may vary.
• Source: PlantsCucurbitaceaeTrichosanthes cucumerina L.