Plasma hydrogenated cationic detonation nanodiamonds efficiently deliver to human cells in culture functional siRNA targeting the Ewing sarcoma junction oncogene

Jean-Rémi Bertrand (1) , Catherine Pioche-Durieu (2) , Juan A. Ayala (1) , Tristan Petit (3) , Hugues Girard (3) , Claude Malvy (1) , Eric Le Cam (2) , François Treussart (4) , Jean-Charles Arnault (3)

1 UMR 8203 - Vectorologie et thérapeutiques anti-cancéreuses [Villejuif]
2 IMC (UMR 8126) - Interactions moléculaires et cancer
3 LCD (CEA, LIST) - Laboratoire Capteurs Diamant (CEA, LIST)
4 LPQM - Laboratoire de Photonique Quantique et Moléculaire

The expression of a defective gene can lead to major cell dysfunctions among which cell proliferation and tumor formation. One promising therapeutic strategy consists in silencing the defective gene using small interfering RNA (siRNA). In previous publications we showed that diamond nanocrystals (ND) of primary size 35 nm, rendered cationic by polyethyleneimine-coating, can efficiently deliver siRNA into cell, which further block the expression of EWS/FLI-1 oncogene in a Ewing sarcoma disease model. However, a therapeutic application of such nanodiamonds requires their elimination by the organism, particularly in urine, which is impossible for 35 nm particles. Here, we report that hydrogenated cationic nanodiamonds of primary size 7 nm (ND-H) have also a high affinity for siRNA and are capable of delivering them in cells. With siRNA/ND-H complexes, we measured a high inhibition efficacy of EWS/FLI-1 gene expression in Ewing sarcoma cell line. Electron microscopy investigations showed ND-H in endocytosis compartments, and especially in macropinosomes from which they can escape before siRNA degradation occurred. In addition, the association of EWS/FLI-1 silencing by the siRNA/ND-H complex with a vincristine treatment yielded a potentiation of the toxic effect of this chemotherapeutic drug. Therefore ND-H appears as a promising delivery agent in anti-tumoral gene therapy.

Mots clés: Nanodiamond; diamond; Plasma hydrogenation; siRNA; Ewing sarcoma; Gene therapy; Drug delivery; Nanomedicine; VINCRISTINE; STABILITY; THERAPY; PATHWAY; diamond biomedical applications

Domaines: Biomatériaux; Micro et nanotechnologies/Microélectronique; Biologie cellulaire

Jean-Rémi Bertrand, Catherine Pioche-Durieu, Juan A. Ayala, Tristan Petit, Hugues Girard, et al.. Plasma hydrogenated cationic detonation nanodiamonds efficiently deliver to human cells in culture functional siRNA targeting the Ewing sarcoma junction oncogene. Biomaterials, 2015, 45, pp.93 - 98. ⟨10.1016/j.biomaterials.2014.12.007⟩. ⟨cea-01807460⟩