Delivery of nanoparticulate drug delivery systems via the intravenous route for cancer gene therapy.

While the systemic route of administration enables therapeutic genes to spread through the bloodstream and access target cells, it is a challenge to achieve this. Several studies demonstrate that systemic administration of therapeutic genes or other nucleic acid-based constructs such as siRNA to solid tumors as well as cancer metastases are better with nanoparticulate systems compared to administration of free (uncomplexed) nucleic acids. Nanoparticle-based nucleic acid delivery systems might be more pertinent, due to the several privileges in terms of enhanced tissue penetrability, improved cellular uptake and to a lesser extent, targeted gene delivery to the cells of interest provided targeting ligands are used. Systemic delivery of nanoplexes has already been reported with different nanoparticles containing DNA via various routes of administration. The goal of the present article is to review the current state of intravenous delivery of nanoparticles for gene therapy of cancer.