The main obstacle to siRNA therapy is in delivering RNA across the cell membrane. Furthermore, new methods for monitoring therapeutic responses are highly desirable. Here we report the development of a multifunctional nanomedicine platform for siRNA targeted delivery to cancerous tumors as well as the use of magnetic resonance imaging (MRI) to monitor the drug therapy outcome. To develop efficient, multifunctional, and nontoxic siRNA delivery agents for cancer therapy, we fabricated different sizes of SPIO nanoparticles, which are good MRI contrast agents. We demonstrated that 5nm SPIO nanoparticles are more efficient in siRNA packaging than the larger ones (10nm) and even fifth generation of polypropyleneimine dendrimers(PPI G5). To integrate targeting groups in the formed siRNA nanoparticles, the condensation efficiency of SPIO nanoparticles mixed with PPI G5 has been studied. The confocal microscopy was used to evaluate the ability of these multifunctional delivery agents in facilitating the siRNAs internalization into cancer cells. More importantly, SPIO nanoparticles and their mixture with PPI G5 significantly suppressed the expression of the corresponding mRNA. We envision that siRNA nanoparticles condensed from SPIO can be used as multifunctional siRNA delivery agents for effective cancer therapy, with the ability to real time monitor the siRNA therapeutic outcome.
Journal: TechConnect Briefs
Volume: 2, Nanotechnology 2008: Life Sciences, Medicine & Bio Materials – Technical Proceedings of the 2008 NSTI Nanotechnology Conference and Trade Show, Volume 2
Published: June 1, 2008
Pages: 49 - 52
Industry sector: Medical & Biotech
Topicss: Biomaterials, Cancer Nanotechnology