These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Addition of S-1 to the epidermal growth factor receptor inhibitor gefitinib overcomes gefitinib resistance in non-small cell lung cancer cell lines with MET amplification.
    Author: Okabe T, Okamoto I, Tsukioka S, Uchida J, Hatashita E, Yamada Y, Yoshida T, Nishio K, Fukuoka M, Jänne PA, Nakagawa K.
    Journal: Clin Cancer Res; 2009 Feb 01; 15(3):907-13. PubMed ID: 19188161.
    Abstract:
    PURPOSE: Most non-small cell lung cancer (NSCLC) tumors with activating mutations in the epidermal growth factor receptor (EGFR) are initially responsive to EGFR tyrosine kinase inhibitors (EGFR-TKI) such as gefitinib and erlotinib, but they almost invariably develop resistance to these drugs. A secondary mutation in EGFR (T790M) and amplification of the MET proto-oncogene have been identified as mechanisms of such acquired resistance to EGFR-TKIs. We have now investigated whether addition of the oral fluoropyrimidine derivative S-1 to gefitinib might overcome gefitinib resistance in NSCLC cell lines. EXPERIMENTAL DESIGN: The effects of gefitinib on EGFR signaling and on the expression both of thymidylate synthase and of the transcription factor E2F-1 in gefitinib-resistant NSCLC cells were examined by immunoblot analysis. The effects of S-1 (or 5-fluorouracil) and gefitinib on the growth of NSCLC cells were examined in vitro as well as in nude mice. RESULTS: Gefitinib induced down-regulation of thymidylate synthase and E2F-1 in gefitinib-resistant NSCLC cells with MET amplification but not in those harboring the T790M mutation of EGFR. The combination of 5-fluorouracil and gefitinib synergistically inhibited the proliferation of cells with MET amplification, but not that of those with the T790M mutation of EGFR, in vitro. Similarly, the combination of S-1 and gefitinib synergistically inhibited the growth only of NSCLC xenografts with MET amplification. CONCLUSIONS: Our results suggest that the addition of S-1 to EGFR-TKIs is a promising strategy to overcome EGFR-TKI resistance in NSCLC with MET amplification.
    [Abstract] [Full Text] [Related] [New Search]