The project aims at studying the combined effect of anti-miRNAs delivered by nanoparticles and ionizing radiation on cancer cells. Polymeric nanoparticles will be synthesized and loaded with an antisense oligonucleotide that will act as an inhibitor of an overexpressed miRNA involved in tumorigenesis and prostate cancer development. The cellular uptake and the effect of such nanoparticles in cell viability will be evaluated as a novel therapeutic approach to prostate cancer. The performance of the deliver y system developed when subjected to radiation will be subsequently studied as well as the cellular response to the integrated approach anti-miRNA / radiation. The design of a nanoparticle-based anti-miRNA delivery system and its combination with radiatio n for cancer therapy are the innovative aspects of the current proposal.