Multidrug transporter ABCG2 prevents tumor cell death induced by the epidermal growth factor receptor inhibitor Iressa (ZD1839, Gefitinib).
Iressa (ZD1839, Gefitinib), used in clinics to treat non-small cell lung cancer patients, is a tyrosine kinase receptor inhibitor that leads to specific decoupling of epidermal growth factor receptor (EGFR) signaling. Recent data indicate that Iressa is especially effective in tumors with certain EGFR mutations; however, a subset of these tumors does not respond to Iressa. In addition, certain populations have an elevated risk of side effects during Iressa treatment. The human ABCG2 (BCRP/MXR/ABCP) transporter causes cancer drug resistance by actively extruding a variety of cytotoxic drugs, and it functions physiologically to protect our tissues from xenobiotics. Importantly, ABCG2 modifies absorption, distribution, and toxicity of several pharmacologic agents. Previously, we showed that ABCG2 displays a high-affinity interaction with several tyrosine kinase receptor inhibitors, including Iressa. Here, we show that the expression of ABCG2, but not its nonfunctional mutant, protects the EGFR signaling-dependent A431 tumor cells from death on exposure to Iressa. This protection is reversed by the ABCG2-specific inhibitor, Ko143. These data, reinforced with cell biology and biochemical experiments, strongly suggest that ABCG2 can actively pump Iressa. Therefore, variable expression and polymorphisms of ABCG2 may significantly modify the antitumor effect as well as the absorption and tissue distribution of Iressa.
Elkind
N Barry
NB
National Medical Center, Institute of Haematology and Immunology, Membrane Research Group of the Hungarian Academy of Sciences, Budapest, Hungary.
Szentpétery
Zsófia
Z
Apáti
Agota
A
Ozvegy-Laczka
Csilla
C
Várady
György
G
Ujhelly
Olga
O
Szabó
Katalin
K
Homolya
László
L
Váradi
András
A
Buday
László
L
Kéri
György
G
Német
Katalin
K
Sarkadi
Balázs
B
D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D018432:Drug Resistance, Multiple / Q000187:drug effects; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000077156:Gefitinib; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D011799:Quinazolines / Q000627:therapeutic use*; D014407:Tumor Cells, Cultured
C116614:ABCG2 protein, human; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D000970:Antineoplastic Agents; D009363:Neoplasm Proteins; D011799:Quinazolines; D000255:Adenosine Triphosphate; D066246:ErbB Receptors; D000077156:Gefitinib