Go Back Gefitinib Purity: 99,0 percent

Product Detail

Gefitinib, or IRESSATM as it is more commonly called, is an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). EGFR is part of the ERBB receptor family, which has four closely related members: EGFR (ERBB1), HER2 (ERBB2), HER3 (ERBB3) and HER4 (ERBB4). These receptors consist of an extracellular ligand-binding domain, a transmembrane domain and an intracellular tyrosine kinase domain. Ligand binding induces dimerization which activates the tyrosine kinase activity. This leads to receptor autophosphorylation and the initiation of signal transduction cascades involved in cell proliferation and survival. EGFR activation has been implicated in processes involved in tumor growth and progression including cell proliferation, inhibition of apoptosis, angiogenesis and metastasis. Gefitinib is an ATP competitive inhibitor of EGFR tyrosine kinaseactivity with an IC50 value of 0.033 ?M (EGFR/HER1) and was shown to effectively inhibit HER1-HER2 heterodimers. HER2 (ErbB2) is inhibited with an IC50 > 3,7 ?M. Gefitinib is widely investigated in non-small cancer of the lung, colon cancer, breast cancer and cancer of the head and neck. In non-small cell lung cancer recent data show its benefit to be limited mostly to adenocarcinoma subsets, patients carrying activating HER1-mutations, nonsmokers and patients of japanese origin. Gefitinib shows extensive tissue distribution. Its concentration in tumor tissue was shown to reach 16 ?M which exceeds its HER1 IC50 by a factor of 500.