Sleeping beauty models of cancer

The many advantages of retroviral insertional mutagenesis have been discussed in the previous chapters, and this strategy has played a significant role in furthering our current understanding of the genetic basis of cancer. However, retroviral insertional mutagenesis has two main limitations that have prevented this approach from being applied to many forms of cancer. First, naturally-occurring slow transforming retroviruses have a restricted cellular tropism within the infected host, thus limiting the types of cells that can be mutagenized by these viruses [29]. Second, retroviruses require the host cell to undergo mitosis in order to gain access to the nuclear genome and integrate as a provirus. The combined effects of these drawbacks have limited the application of retroviral insertional mutagenesis to the study of hematopoietic malignancies and mammary cancer in mice.