Cat No.
CEI-0052
Description
Gefitinib (Iressa) can inhibit EGFR with IC50 of 33 nM.
Alias
ZD-1839
Synonyms
ZD-1839
CAS No.
184475-35-2
Targets
EGFR
Chemical Name
N-(3-chloro-4-fluorophenyl)-7-methoxy-6-(3-morpholinopropoxy)quinazolin-4-amine
M.Wt
446.9
Purity
>99%
Solubility
DMSO 89 mg/mL Water
Storage
2 years at -20centigrade Powder
In vitro
As a quinazoline tyrosine kinase inhibitor selective for the EGFR, Gefitinib (ZD1839) can inhibit EGFR with IC50 of 33 nM by binding to the adenosine triphosphate (ATP)-binding site of EGFR. For HER2, Gefitinib (ZD1839) does not show strong inhibition. Actually, Gefitinib (ZD1839) inhibits HER2 with IC50 more than 1000 nM. Even showing weekly inhibition to HER2, Gefitinib (ZD1839) still inhibits HER2 phosphorylation and growth in HER2-overexpressing breast tumor cells that coexpress EGFR. As EGFR is the upsteam target of Ras signaling pathway, blocking the EGFR with Gefitinib (ZD1839) can inhibit tumor cell proliferation. In a panel of human breast cancer and other epithelial tumor cell lines, HER2-overexpressing tumors were particularly sensitive to ZD1839. Growth inhibition of these tumor cell lines was associated with the dephosphorylation of EGFR, HER2, and HER3, accompanied by the loss of association of HER3 with phosphatidylinositol 3-kinase, and down-regulation of Akt activity.
In vivo
Treating cell lines (including SKBR-3, MDA-361, and BT-474 cells) with 1000nM ZD1839 induced substantial loss of HER2 tyrosine phosphorylation without a change in HER2 levels. Comparing to herceptin, which is a monoclonal antibody against the HER2, Gefitinib (ZD1839) shows greater inhibition.
