Description
Cucurbitacin B is a tetracyclic triterpenoid that has been shown to have a strong antitumor activity.
Chemical Properties
White solid
Uses
Cucurbitacin B hydrate has been used:
- as a signal transducer and activator of transcription 3 (stat3) inhibitor to determine its effect on the expression of human lysosomal acid lipase (hLAL) in myeloid-derived suppressor cells (MDSCs).
- as an ecdysone receptor (EcR) antagonist injection to lower the levels of 20-hydoxyecdysone (20E) signaling in butterflies.
- to determine its effect on the cell viability of pancreatic cancer cell lines.
Definition
ChEBI: A cucurbitacin in which a lanostane skeleton is multi-substituted with hydroxy, methyl and oxo substituents, with unsaturation at positions 5 and 23; a hydroxy function at C-25 is acetylated.
Biochem/physiol Actions
Cucurbitacin B is a triterpenoid constituent of Cucurbitaceae plant species. Cucurbitacin B inhibits proliferation in a wide variety of tumor cell lines (IC50 15-30 nM) by inducing apoptosis and inducing cell cycle arrest at G2/M phase. Although the mechanism of action is unclear, Cucurbitacin B inhibits STAT 3 phosphorylation and expression levels and has been shown to block JAK2 activity. Curcubitacin B also inhibits the transcriptional activity of HIF1a and Nf-KB. Curcubitacin B is structurally similar to the JAK inhibitor Curcubitacin I.