Activation of HER family signaling as a mechanism of acquired resistance to ALK inhibitors in EML4-ALK-positive non-small cell lung cancer

Junko Tanizaki, Isamu Okamoto, Takafumi Okabe, Kazuko Sakai, Kaoru Tanaka, Hidetoshi Hayashi, Hiroyasu Kaneda, Ken Takezawa, Kiyoko Kuwata, Haruka Yamaguchi, Erina Hatashita, Kazuto Nishio, Kazuhiko Nakagawa

研究成果: ジャーナルへの寄稿記事

101 引用 (Scopus)


Purpose: Anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKI) such as crizotinib show marked efficacy in patients with non-small cell lung cancer positive for the echinoderm microtubule-associated protein-like 4 (EML4)-ALK fusion protein. However, acquired resistance to these agents has already been described in treated patients, and the mechanisms of such resistance remain largely unknown. Experimental Design: We established lines of EML4-ALK-positive H3122 lung cancer cells that are resistant to the ALK inhibitor TAE684 (H3122/TR cells) and investigated their resistance mechanism with the use of immunoblot analysis, ELISA, reverse transcription and real-time PCR analysis, and an annexin V binding assay. We isolated EML4-ALK-positive lung cancer cells (K-3) from a patient who developed resistance to crizotinib and investigated their characteristics. Results: The expression of EML4-ALK was reduced at the transcriptional level, whereas phosphorylation of epidermal growth factor receptor (EGFR), HER2, and HER3 was upregulated, in H3122/TR cells compared with those in H3122 cells. This activation of HER family proteins was accompanied by increased secretion of EGF. Treatment with an EGFR-TKI induced apoptosis in H3122/TR cells, but not in H3122 cells. The TAE684-induced inhibition of extracellular signal-regulated kinase (ERK) and STAT3 phosphorylation observed in parental cells was prevented by exposure of these cells to exogenous EGF, resulting in a reduced sensitivity of cell growth to TAE684. K-3 cells also manifested HER family activation accompanied by increased EGF secretion. Conclusions: EGF-mediated activation of HER family signaling is associated with ALK-TKI resistance in lung cancer positive for EML4-ALK.

ジャーナルClinical Cancer Research
出版物ステータス出版済み - 11 15 2012


All Science Journal Classification (ASJC) codes

  • Oncology
  • Cancer Research