Jordi Codony-Servat1, Carles Codony-Servat2, Andrés Felipe Cardona3, Ana Giménez-Capitán2, Ana Drozdowskyj4, Jordi Berenguer2, Jillian Wilhelmina Paulina Bracht2, Masaoki Ito5, Niki Karachaliou6, Rafael Rosell7. 1. Pangaea Oncology, Laboratory of Molecular Biology, Quirón-Dexeus University Institute, Barcelona, Spain. Electronic address: jcodony@panoncology.com. 2. Pangaea Oncology, Laboratory of Molecular Biology, Quirón-Dexeus University Institute, Barcelona, Spain. 3. Clinical and Translational Oncology Group, Thoracic Oncology Unit, Institute of Oncology, Clínica del Country, Bogotá, Colombia; Foundation for Clinical and Applied Cancer Research (FICMAC), Bogotá, Colombia. 4. Institut d'Investigació en Ciències Germans Trias i Pujol, Badalona, Spain. 5. Pangaea Oncology, Laboratory of Molecular Biology, Quirón-Dexeus University Institute, Barcelona, Spain; Department of Surgical Oncology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan. 6. Pangaea Oncology, Laboratory of Molecular Biology, Quirón-Dexeus University Institute, Barcelona, Spain; Instituto Oncológico Dr Rosell (IOR), University Hospital Sagrat Cor, Quiron Salud Group Barcelona, Barcelona, Spain. 7. Pangaea Oncology, Laboratory of Molecular Biology, Quirón-Dexeus University Institute, Barcelona, Spain; Instituto Oncológico Dr Rosell (IOR), Quirón-Dexeus University Institute, Barcelona, Spain; Institut d'Investigació en Ciències Germans Trias i Pujol, Badalona, Spain; Institut Català d'Oncologia, Hospital Germans Trias i Pujol, Badalona, Spain. Electronic address: rrosell@iconcologia.net.
Abstract
INTRODUCTION: Epidermal growth factor receptor (EGFR) pathway deregulation promotes the acquisition of stemlike properties in non-small-cell lung cancer. EGFR inhibition through NOTCH enriches lung cancer stem cells (CSCs). Src through Yes-associated protein 1 (YAP1) activates NOTCH. Signal transduction and activator of transcription 3 (STAT3) activation occurs upon EGFR blockade and regulates the generation of CSCs. PATIENTS AND METHODS: Using the Aldefluor assay kit, we investigated the enrichment of aldehyde dehydrogenase (ALDH)-positive cells in EGFR-mutation-positive cells treated with gefitinib, afatinib, and osimertinib. Western blot analysis was performed to evaluate changes in CSC marker expression upon EGFR blockade. We performed gene expression analysis in a cohort of EGFR-mutation-positive non-small-cell lung cancer patients. We evaluated the association of gene expression with treatment outcomes. RESULTS: The cell subpopulation surviving EGFR inhibition had high ALDH activity and elevated CSC marker expression. Concurrent inhibition of EGFR, STAT3, and Src diminished the CSC subpopulation in an EGFR-mutation-positive cellular model. In a cohort of 64 EGFR-mutation-positive patients, 2 ALDH1 isoforms and the NOTCH target hairy and enhancer of split 1 (HES1), when highly expressed, were predictive of worse outcome to EGFR blockade. The gene expression of B-cell-specific Moloney murine leukemia virus integration site 1 (Bmi-1) that maintains the self-renewal of stem cells was also related to treatment outcome. CONCLUSION: Single EGFR inhibitors increase the population of CSCs. Combinatory therapy targeting STAT3 and Src may be of potential benefit. ALDH1, HES1, and Bmi-1 are essential biomarkers in the initial assessment of EGFR-mutation-positive patients.
INTRODUCTION:Epidermal growth factor receptor (EGFR) pathway deregulation promotes the acquisition of stemlike properties in non-small-cell lung cancer. EGFR inhibition through NOTCH enriches lung cancer stem cells (CSCs). Src through Yes-associated protein 1 (YAP1) activates NOTCH. Signal transduction and activator of transcription 3 (STAT3) activation occurs upon EGFR blockade and regulates the generation of CSCs. PATIENTS AND METHODS: Using the Aldefluor assay kit, we investigated the enrichment of aldehyde dehydrogenase (ALDH)-positive cells in EGFR-mutation-positive cells treated with gefitinib, afatinib, and osimertinib. Western blot analysis was performed to evaluate changes in CSC marker expression upon EGFR blockade. We performed gene expression analysis in a cohort of EGFR-mutation-positive non-small-cell lung cancerpatients. We evaluated the association of gene expression with treatment outcomes. RESULTS: The cell subpopulation surviving EGFR inhibition had high ALDH activity and elevated CSC marker expression. Concurrent inhibition of EGFR, STAT3, and Src diminished the CSC subpopulation in an EGFR-mutation-positive cellular model. In a cohort of 64 EGFR-mutation-positive patients, 2 ALDH1 isoforms and the NOTCH target hairy and enhancer of split 1 (HES1), when highly expressed, were predictive of worse outcome to EGFR blockade. The gene expression of B-cell-specific Moloney murine leukemia virus integration site 1 (Bmi-1) that maintains the self-renewal of stem cells was also related to treatment outcome. CONCLUSION: Single EGFR inhibitors increase the population of CSCs. Combinatory therapy targeting STAT3 and Src may be of potential benefit. ALDH1, HES1, and Bmi-1 are essential biomarkers in the initial assessment of EGFR-mutation-positive patients.