Ontology highlight
ABSTRACT: Background
The sensitivity of non-small cell lung cancer (NSCLC) patients to EGFR tyrosine kinase inhibitors (TKIs) is strongly associated with activating EGFR mutations. Although not as sensitive as patients harboring these mutations, some patients with wild-type EGFR (wtEGFR) remain responsive to EGFR TKIs, suggesting that the existence of unexplored mechanisms renders most of wtEGFR-expressing cancer cells insensitive.Methodology/principal findings
Here, we show that acquired resistance of wtEGFR-expressing cancer cells to an EGFR TKI, gefitinib, is associated with elevated expression of breast cancer resistance protein (BCRP/ABCG2), which in turn leads to gefitinib efflux from cells. In addition, BCRP/ABCG2 expression correlates with poor response to gefitinib in both cancer cell lines and lung cancer patients with wtEGFR. Co-treatment with BCRP/ABCG2 inhibitors enhanced the anti-tumor activity of gefitinib.Conclusions/significance
Thus, BCRP/ABCG2 expression may be a predictor for poor efficacy of gefitinib treatment, and targeting BCRP/ABCG2 may broaden the use of gefitinib in patients with wtEGFR.
SUBMITTER: Chen YJ
PROVIDER: S-EPMC3121773 | biostudies-literature | 2011
REPOSITORIES: biostudies-literature
Chen Yun-Ju YJ Huang Wei-Chien WC Wei Ya-Ling YL Hsu Sheng-Chieh SC Yuan Ping P Lin Heather Y HY Wistuba Ignacio I II Lee J Jack JJ Yen Chia-Jui CJ Su Wu-Chou WC Chang Kwang-Yu KY Chang Wen-Chang WC Chou Tse-Chuan TC Chou Chao-Kai CK Tsai Chang-Hai CH Hung Mien-Chie MC
PloS one 20110623 6
<h4>Background</h4>The sensitivity of non-small cell lung cancer (NSCLC) patients to EGFR tyrosine kinase inhibitors (TKIs) is strongly associated with activating EGFR mutations. Although not as sensitive as patients harboring these mutations, some patients with wild-type EGFR (wtEGFR) remain responsive to EGFR TKIs, suggesting that the existence of unexplored mechanisms renders most of wtEGFR-expressing cancer cells insensitive.<h4>Methodology/principal findings</h4>Here, we show that acquired ...[more]