Table 1.

Biochemical IC50 values for inhibition of KIT kinase activity in transfected cells

1° Mutation2° MutationImatinibSorafenibSunitinib
V560DNone<100<100<100
V560DV654A1,600560a<100
V560DT670I>5,000200a<100
V560DD816H1,9901,930>1,000
V560DD820A4,000<100ND
V560DD820G3,255480a>1,000
V560DN822K2,820480a>1,000
V560DY823D2,100280a>1,000
WTNone3,4002,700<100
D816VNone>5,000>5,000>1,000
KIT insAY502-503None3,9701,829a<100
KIT insAY502-503V654A3,100590a100
KIT insAY502-503D816H4,9301,820a>1,000
KIT insAY502-503D820G2,6401,380aND

NOTE: The values for imatinib, sorafenib, and sunitinib represent the biochemical IC50 expressed in nmol/L units for the listed single mutant or compound mutant kinases. WT indicates the results for wild-type (unmutated), KIT ligand-stimulated KIT kinase. The IC50 values for imatinib and sorafenib are from direct head-to-head comparison from a minimum of 3 replicate experiments. The IC50 values for sunitinib are from a previous publication from our group (6).

Abbreviation: ND, not determined.

  • aP < 0.05 sorafenib IC50 compared with imatinib IC50.