Glioma-initiating cells support glioblastoma heterogeneity at the level of integrin α5β1

Transcription

1 Glioma-initiating cells support glioblastoma heterogeneity at the level of integrin α5β1 MERCIER Marie-Cécile, 2th year PhD student Laboratoire de Biophotonique et Pharmacologie, UMR7213 CNRS Faculty of Pharmacy, University of Strasbourg, Team Tumoral signaling and therapeutic targets (Monique DONTENWILL)

2 Glioblastoma (GBM) - The most aggressive brain tumor - Standard treatment (protocol Stupp) Surgery TMZ adjuvant * * * * * * weeks TMZ + RT - Survival < 15months - Highly invasive and resistant to apoptosis - Recurrence Treatment failure due to heterogeneity?

3 Intertumoral heterogeneity different therapeutic responses GBM heterogeneity Mesenchymal subgroup the most agressive Verhaak et al, 2010 Intratumoral heterogeneity From sensitive to resistant clones Mesenchymal subclone the most resistant Segerman et al, 2016

4 α5β1 integrin in GBM Preclinical data Implicated in resistance to chemotherapy, in migration/invasion Renner et al, 2016; Blandin et al, 2016; Janouskova et al, 2012 Intertumoral heterogeneity Intratumoral heterogeneity Integrin α5 expression (mrna) is a marker of resistance (TCGA dataset) Integrin α5 expression (protein) is heterogenous in one single tumor Is α5 expression heterogeneity linked to GIC heterogeneity?

5 Glioma Initiating Cells (GIC) = stem-like cells Is α5 expression heterogeneity linked to GIC heterogeneity?

6 α5β1 integrin expression in GIC Stem condition / undifferentiated After Differentiation (FBS) Neurospheres NCH421k Adherent cells NCH N13 SRA5 SRB1 SRC3 SB7 ITGA5 GFA P GAPDH FBS - + Heidelberg Paris Toulouse + α5 expression after differentiation is heterogenous in different GICs

7 Role of α5 in GIC (in vitro) m R N A fo ld in c re a s e ns G IC * N C H k N C H No α5 expression α5 expression NCH421k 3731 NCH FBS α5 expression after differentiation associated with high level of a5 RNA in GIC fo ld in c re a s e v ia b le c e lls a t d a y 7 (v s d a y 0 ) P r o life r a tio n * ** N C H k N C H k m ig ra tin g c e lls M ig r a tio n N C H k N C H * α5 programmation in GIC induces an increased capacity of proliferation and migration of cells after differentiation

8 Role of α5 in GIC (in vitro) α5 NCH421k NCH421kα5 Forced expression of α5 integrin in NCH421k GIC GAPDH FBS NCH421kα5 α5 GAPDH Siα5 (25nM) - + NCH421k NCH421kα5 NCH421kα5 GIC GIC differentiated fo ld in c re a s e v ia b le c e lls a t d a y 7 (v s d a y 0 ) 8 0 **** ** P r o life r a tio n N C H k m o c k N C H k 5 N T N C H k 5 s i 5 α5 integrin in NCH421k cells increases proliferation which is inhibited by si-rna α5

9 Role of α5 in GIC (in vivo) 104 cells 5weeks NCH421k NCH421k-α5 control + α5 antagonist Hematoxylin/eosin Human cell specific marker Ab Stem121 α5 integrin Ab IIA1 α5 integrin expression in GIC confers tumorigenic potential which is inhibited by α5 antagonist

10 α5 expression involves in GBM aggressiveness NCH421k m R N A fo ld in c re a s e PN s te m m a r k e r s MES N C H k N C H k 5 PN PN NCH421kα5 0.0 m R N A fo ld in c re a s e C D * n e s tin s o x 2 o c t4 C D o lig 2 P D G F R a C D 4 4 si-rna α5 increases CD133 Si-RNA α5 decreased CD44 m R N A fo ld in c re a s e C D 4 4 ** 0 N T 2 4 h 4 8 h 0.0 N T 2 4 h 4 8 h s i-r N A 5 (2 5 n M ) s i-r N A 5 (2 5 n M ) α5 integrin expression induces a switch from proneural to mesenchymal stem cells

11 α5 expression involves in GBM aggressiveness NCH421k m R N A fo ld in c re a s e s te m m a r k e r s MES N C H k N C H k 5 PN PN PN NCH421kα n e s tin Proneural marker s o x 2 o c t4 C D o lig 2 P D G F R a C D 4 4 Mesenchymal markers NCH421K NCH421kα OLIG2 ASCL1 NCAM1 GALNT13 SOX8 SC63 SerpinE1 TGFBI FOSL2 TAGLN2 MYL9 α5 integrin expression induces a switch from proneural to mesenchymal stem cells

12 Conclusion Integrin α5β1 programmation in GIC confers agressive properties to GBM Integrin α5β1 is associated with mesenchymal subtype Therapy against α5β1 is a potentiel therapy for a subpopulation of GBM patients with high α5β1 integrin expression α5 antagonist

13 «Integrins and cancer» team Collaborations Xénogreffes D. GUENOT D. (Strasbourg) Stem cells Dr HEROLD-MENDE C. (Heidelberg) Dr LEMARIE A. (Toulouse) Dr IDBAIH A. (Paris) Sophie MARTIN Isabelle LELONG-REBEL Maxime LEHMANN Laurence CHOULIER Nelly ETIENNE-SELLOUM Fanny NOULET Florence SCHAFFNER Marie-Cécile MERCIER Anne-Florence BLANDIN Guillaume RENNER