RNA Interference with siRNA

Over the last decade, RNA interference has emerged as an effective mechanism for silencing gene expression. This ancient cellular antiviral response can be used to allow specific inhibition of the function of any chosen target gene, including those involved in diseases such as cancer, AIDS and hepatitis. It has become an invaluable research tool to aid in the identification of novel genes involved in disease processes. It has advanced from the use of synthetic RNA for the endogenous production of small hairpin RNA by plasmid and viral vectors, and from transient inhibition in vitro to longer-lasting effects in vivo. However, as with antisense and ribozymes, the efficient delivery of siRNA into cells is currently the limiting factor to successful gene expression inhibition in vivo. This review gives an overview of the mechanism of action of siRNA and its use in cancer research. It also discusses the successes and shortcomings of this new gene knockdown tool.