RNAi is a mechanism displayed by most eukaryotic cells to rid themselves of foreign double-strand RNA molecules. In the 11 years since the initial report, RNAi has now been demonstrated to function in mammalian cells to alter gene expression and used as a means for genetic discovery as well as a possible strategy for genetic correction and genetic therapy in cancer and other diseases. The aim of this review is to provide a general overview of how RNAi suppresses gene expression, examine some published RNAi approaches that have resulted in changes in stem cell function, and suggest the possible clinical relevance of this work in cancer therapy through targeting cancer stem cells.
