Oligonucleotides Targeted Against a Junction Oncogene Are Made Efficient by Nanotechnologies
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Purpose. Antisense oligonucleotides (AON) against junction EWS-Fli-1 oncogene (which is responsible for the Ewing Sarcoma) are particularly interesting for targeting chromosomal translocations that are only found in tumor cells. However, these AON have proved in the past to be ineffective in vivo because of their susceptibility to degradation and their poor intracellular penetration. The aim of this study was to improve the delivery of these molecules through the use of nanotechnologies.
Method. Two different AONs, and their controls, both targeted against the junction area of the fusion gene EWS-Fli-1 were used. Nanocapsules were employed to deliver a phosphorothioate AON and its control. The nanospheres were used to deliver a chimeric phosphorothioate, phosphodiester AON, with 5 additional bases in 5′ which allow this AON to be structured with a loop. These formulations were injected intratumorally to nude mice bearing the experimental EWS-Fli-1 tumor. The tumour volume was estimated during the experiments by two perpendicular measurements length (a) and width (b) of the tumour and was calculated as ab2/2. Northern blot analysis was also performed after removing the tumors 24 h after the treatment with a single dose of AON either free or associated with nanotechnologies.
Results. This study shows for the first time that AON against EWS-Fli-1 oncogene may inhibit with high specificity the growth of an EWS-Fli-1 dependent tumor grafted to nude mice provided they are delivered by nanocapsules or nanospheres. In this experience, the antisense effect was confirmed by the specific down regulation of EWS-Fli-1 mRNA.
Conclusion. Thus, both nanocapsules and nanospheres may be considered as promising systems for AON delivery in vivo.
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- 1.K. Tanaka, T. Iwakuma, K. Harimaya, H. Sato, and Y. Iwamoto. EWS-Fli1 antisense oligodeoxynucleotide inhibits proliferation of human Ewing's sarcoma and primitive neuroectodermal tumor cells. J. Clin. Invest. 99:239-247 (1997).Google Scholar
- 2.A. V. Maksimenko, M. B. Gottikh, V. Helin, Z. A. Shabarova, and C. Malvy. Physico-chemical and biological properties of antisense phosphodiester oligonucleotides with various secondary structures. Nucleosides Nucleotides 18:2071-2091 (1999).Google Scholar
- 3.C. Chavany, T. Le Doan, P. Couvreur, F. Puisieux, and C. Hélène. Polyalkylcyanoacrylate nanoparticles as polymeric carriers for antisense oligonucleotides. Pharm. Res. 9:441-449 (1992).Google Scholar
- 4.G. Lambert, J. R. Bertrand, E. Fattal, F. Subra, H. Pinto-Alphandary, C Malvy, C. Auclair, and P. Couvreur. EWS Fli-1 antisense nanocapsules inhibit Ewing sarcoma-related tumor in mice. Biochem. Biophys. Res. Com. 279:401-406 (2000).Google Scholar
- 5.G. Lambert, E. Fattal, H. Pinto-Alphandary, A. Gulik, and P. Couvreur. Polyisobutylcyanoacrylate nanocapsules containing an aqueous core as a novel colloidal carrier for the delivery of oligonucleotides. Pharm. Res. 17:707-714 (2000).Google Scholar