Chapter Cellular Barriers for Nucleic Acid Delivery and Targeting
Gene transfer is the key technology in the genetic modication of organisms for experimental and therapeutic purposes. Gene therapy holds great promise in medicine, since the exploration of the human genome and post-genomic biology continues to reveal new mechanisms and intervention strategies about the diseases. This approach is a new paradigm in pharmaceutical therapy, since it avoids the extensive search for new pharmacologically active molecules against a target. In the case of gene therapy, the information about the mechanism of the disease reveals the endogenous drug (i.e., the under-expressed or inappropriate gene) in the disease state. The expression can be replenished by providing extra genetic material by gene transfer. For example, the vascular endothelial growth factor (VEGF) gene can be used to induce neo-vessel formation, neurotrophic growth factor genes to revive degenerated neural tissue, and the tyrosin kinase “suicide” genes for rendering the cancer cells susceptible to anticancer drugs.