1275PD - Stemness characterization of tumorspheres from non-small cell lung cancer. Differential expression in CSC-related markers and signaling pathways.

Date 11 September 2017
Event ESMO 2017 Congress
Session Non-metastatic NSCLC and other thoracic malignancies
Topics Cancer in Adolescents
Non-Small-Cell Lung Cancer, Early Stage
Lung and other Thoracic Tumours
Translational Research
Presenter ALEJANDRO HERREROS POMARES
Citation Annals of Oncology (2017) 28 (suppl_5): v453-v456. 10.1093/annonc/mdx381
Authors A. HERREROS POMARES1, S. Calabuig Fariñas2, E. Escorihuela3, H. Amado1, R. Guijarro4, S. Gallach Garcia3, A. Navarro5, E. Jantus-Lewintre6, C. Camps Herrero7
  • 1Laboratorio De Oncología Molecular, Fundación de Investigación Hospital General Universitario de Valencia, 46014 - Valencia/ES
  • 2Laboratorio De Oncología Molecular; Fundación De Investigación Hospital General Universitario De Valencia-ciberonc, Departamento de Patología, Universitat de València;, 46014 - Valencia/ES
  • 3Laboratorio De Oncología Molecular, Fundación de Investigación Hospital General Universitario de Valencia-CIBERONC, 46014 - Valencia/ES
  • 4Departamento De Cirugía, Universidad De Valencia, Servicio de Cirugía Torácica, Hospital General Universitario de Valencia-CIBERONC;, 46014 - Valencia/ES
  • 5Servicio De Anatomía Patológica, Hospital General Universitario de Valencia, 46014 - Valencia/ES
  • 6Laboratorio De Oncología Molecular, Fundación Para La Investigación, Hospital General Universitario De Valencia-ciberonc, Departamento de Biotecnología, Universidad Politécnica de Valencia;, 46014 - Valencia/ES
  • 7Laboratorio De Oncología Molecular, Fundación Para La Investigación, Hospital General Universitario De Valencia-ciberonc, Departamento de Medicina, Universidad de Valencia; Servicio de Oncología Médica, Hospital Hospital General Universitario de Valencia, 46014 - Valencia/ES

Abstract

Background

Treatment resistance and relapse have been associated to cancer stem cells (CSCs), a highly tumorigenic subpopulation of cells with self-renewal properties and the ability to grow forming tumorspheres in non-adherent conditions. The aim of this study was to isolate and characterize CSCs from lung cancer cell lines and tumor-tissue from resectable non-small cell lung cancer (NSCLC).

Methods

The study was performed on tumour cells from 8 resected NSCLC patients and 12 NSCLC cell lines grown in monolayer and as spheroids. The expression of 60 genes, including CSC-markers, pluripotency inducers, cell cycle regulators, invasion promoters and components of Notch, Wnt and Hedgehog pathways was analysed by RTqPCR. In addition, protein levels of CSC-markers (ALDH1A1, CD133, CD166, CD44 and EpCAM), pluripotency inducers (Nanog, Oct-4 and Sox2), Wnt components (Wnt3 and β-catenin) and Notch1 were assessed by western blot and immunofluorescence.

Results

Lung tumorspheres had significantly higher expression levels of CSC-related genes EPCAM1, CD44, ALDH1A1, CDKN1A, CCND1, and KLF4 compared to their paired-adherent cells. Similarly, epithelial to mesenquimal transition (EMT) inducer SNAI1 and integrins ITGA2, ITGA6 and ITGB1 were overexpressed in lungspheres. Notch pathway ligands, JAG1 and DLL4, receptors, NOTCH1, NOTCH2 and NOTCH3, and the effector factor HES1 showed increased expression in spheroids. In Wnt, higher expression levels of WNT3, CTNNB1 and GSK3B were found in tumorspheres. No significant differences were found for the rest of genes analyzed. Western blot and immunofluorescence analyses revealed that CD44, CD133, Sox2 and β-catenin were highly expressed in spheroids from cell lines and patients’ samples. The expression of the rest of proteins evaluated differed among specimens.

Conclusions

Our results suggest four molecules which could act as markers for CSCs in NSCLC. Genes related to Notch and Wnt signaling pathways were more expressed in spheroids compared to the cells grown in adherence, suggesting that both pathways could be interesting targets against lung CSCs. Supported by grants RD12/0036/0025 from RTICC-FEDER, and PI12-02838 and PI15-00753 from ISCIII.

Clinical trial identification

Legal entity responsible for the study

Fundación de Investigación Hospital General Universitario de Valencia.

Funding

Supported by grants RD12/0036/0025 from RTICC-FEDER, and PI12-02838 and PI15-00753 from ISCIII.

Disclosure

All authors have declared no conflicts of interest.