A novel tumor suppressor function of Kindlin-3 in solid cancer

// Ibtissem Djaafri 1,2,* , Farah Khayati 1,2,3,* , Suzanne Menashi 4 , Jorg Tost 5,6 , Marie-Pierre Podgorniak 3 , Aurelie Sadoux 1,3 , Antoine Daunay 6 , Luis Teixeira 7 , Jean Soulier 2,8 , Ahmed Idbaih 9,10 , Niclas Setterblad 1,2 , Francoise Fauvel 1,2 , Fabien Calvo 1,2 , Anne Janin 2,11,12 , Celeste Lebbe 2,13,14 and Samia Mourah 1,2 1 Inserm UMR-S 940 Paris, France 2 Institute of Hematology (IUH), U niversite Paris-Diderot, Sorbonne Paris Cite, Paris, France 3 AP-HP, Hopital Saint-Louis, Laboratoire de Pharmacologie-Genetique, Paris, France 4 Universite Paris Est Creteil, CNRS-UMR; Creteil, France 5 Laboratory for Epigenetics, Centre National de Genotypage, CEA-Institut de Genomique, Evry, France 6 Laboratory for Functional Genomics, Fondation Jean Dausset - CEPH, Paris, France 7 AP-HP ; Hopital Saint-Louis, Service d’oncologie medicale, Paris, France 8 Hematology Laboratory APHP, Saint-Louis Hospital, Paris, France 9 AP-HP, Groupe Hospitalier Pitie-Salpetriere, Service de Neurologie 2-Mazarin, Paris, France 10 Inserm U 975, Paris, 75013 France, CNRS, UMR, Paris, France 11 Inserm, U728, Paris, France 12 AP-HP, Hopital Saint-Louis, Laboratoire de Pathologie, Paris, France 13 AP-HP, Hopital Saint-Louis, Departement de Dermatologie, Paris, France 14 Inserm U976, Paris, France * These Authors contributed equally to this work Correspondence: Samia Mourah, email: // Keywords : Tumor suppressor gene, Kindlin-3, Invasion/Migration, metastasis, Integrins Received : May 26, 2014 Accepted : June 18, 2014 Published : June 20, 2014 Abstract Kindlin-3 (FERMT-3) is known to be central in hemostasis and thrombosis control and its deficiency disrupts platelet aggregation and causes Leukocyte Adhesion Deficiency disease. Here we report that Kindlin-3 has a tumor suppressive role in solid cancer. Our present genetic and functional data show that Kindlin-3 is downregulated in several solid tumors by a mechanism involving gene hypermethylation and deletions. In vivo experiments demonstrated that Kindlin-3 knockdown in 2 tumor cell models (breast cancer and melanoma) markedly increases metastasis formation, in accord with the in vitro increase of tumor cell malignant properties. The metastatic phenotype was supported by a mechanism involving alteration in β3-integrin activation including decreased phosphorylation, interaction with talin and the internalization of its active form leading to less cell attachment and more migration/invasion. These data uncover a novel and unexpected tumor suppressor role of Kindin-3 which can influence integrins targeted therapies development.