In the study, published Monday (May 1) in Nature Biotechnology, Luo and colleagues set their sights on two fusions genes they had previously found to be associated with prostate cancer and various forms of rapid and invasive cancer, including liver tumors. Using a modified CRISPR-Cas9 tool that creates a single- rather than double-stranded break in DNA, they targeted the chromosomal breakpoints that form these fusion genes and replaced fusion DNA with a gene encoding the enzyme HSV1-tk.
This enzyme effectively kills tumor cells by converting the drug ganciclovir into its active form, which then blocks DNA synthesis and leads to cell death. (Ganciclovir is used to treat cytomegalovirus in humans.)
Scientists have discovered that the newly found Tapanuli
orangutan of Sumatra is more closely related to its cousins in
Borneo than it is to its fellow Sumatran apes. The Tapanuli
population numbers only around 800 individuals.