Table 1

Inhibition of ERBB kinases by HKI-272a

EnzymeIC50 (nm)b
HER-259 ± 13 (n = 5)
Epidermal growth factor receptor92 ± 17 (n = 5)
  • a Purified recombinant COOH-terminal fragments of HER-2 and epidermal growth factor receptor were incubated with ATP in the absence or presence of a range of compound concentrations. Autophosphorylation of the receptors was determined using phospho-tyrosine antibodies. The concentration of compound that inhibits phosphorylation by 50% is shown.

  • b Mean and SE with the number of independent determinations in parentheses.