Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.

Butein, a specific protein tyrosine kinase inhibitor.

Yang E.B., Zhang K., Cheng L.Y., Mack P.

Butein, a plant polyphenol, was shown to be a specific protein tyrosine kinase inhibitor. This compound inhibited not only the epidermal growth factor (EGF)-stimulated auto-phosphotyrosine level of EGF receptor in HepG2 cells but also tyrosine-specific protein kinase activities of EGF receptor (IC50 = 65 microM) and p60c-src (IC50 = 65 microM) in vitro. The inhibition was competitive to ATP and non-competitive to the phosphate acceptor, poly (Glu, Ala, Tyr) 6:3:1 for EGF receptor tyrosine kinase. In contrast, butein non-significantly inhibited the activities of serine- and threonine-specific protein kinases, such as protein kinase C (PKC) and cAMP-dependent protein kinase (PKA).

Biochem. Biophys. Res. Commun. 245:435-438(1998) [PubMed] [Europe PMC]