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Establishment and Characterization of Three Afatinib-resistant Lung Adenocarcinoma PC-9 Cell Lines Developed with Increasing Doses of Afatinib
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RAF1-MEK1-ERK/AKT axis may confer NSCLC cell lines resistance to erlotinib

Zhi-Hong Xu1, Jun-Biao Hang, Jia-An Hu

  • 1Department of Geriatrics, Ruijin Hospital affiliated to Shanghai JiaoTong University, Shanghai, China.

International Journal of Clinical and Experimental Pathology
|August 8, 2013
PubMed

Insights

Advanced non-small cell lung cancer (NSCLC) patients with wild-type EGFR may benefit from erlotinib. This study identified the RAF1-MEK1-ERK/AKT pathway activation as a resistance mechanism, offering potential biomarkers for patient selection.

Area of Science:

  • Oncology
  • Molecular Biology
  • Genetics

Background:

  • Advanced non-small cell lung cancer (NSCLC) patients with wild-type epidermal growth factor receptor (EGFR) can respond to erlotinib therapy.
  • Identifying predictive biomarkers is crucial for patient selection and optimizing erlotinib treatment efficacy.

Purpose of the Study:

  • To investigate molecular mechanisms underlying erlotinib resistance in NSCLC cell lines with wild-type EGFR.
  • To identify potential biomarkers for predicting response to erlotinib therapy.

Main Methods:

  • Microarray analysis of three NSCLC cell lines (U1752, Calu-6, NCI-H292) with wild-type EGFR and varying erlotinib sensitivities.
  • Differential gene expression analysis and Ingenuity Pathway Analysis (IPA) to identify enriched pathways.
  • Immunoblotting to validate the activation of key signaling molecules.

Main Results:

  • Differential gene expression analysis revealed 353 altered genes between erlotinib-sensitive and resistant cell lines.
  • IPA indicated enrichment in epithelial-mesenchymal transition (EMT), Wnt-β catenin, and Tec kinase signaling pathways.
  • Activation of the RAF1-MEK1-ERK/AKT signaling axis was predicted and confirmed in erlotinib-resistant cell lines.

Conclusions:

  • Activation of the RAF1-MEK1-ERK/AKT pathway is a potential mechanism of erlotinib resistance in NSCLC with wild-type EGFR.
  • This pathway activation may serve as a predictive biomarker for erlotinib therapy.
  • Targeting this axis could offer new therapeutic strategies for resistant NSCLC.
Keywords:
AKTEGFRERKMAP2K1NSCLCNon-small cell lung cancerRAF1erlotinibmicroarray

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