Jump-starting cancer-gene discovery

A 'jumping gene' has been harnessed to identify the genes most commonly impaired in liver tumors. The approach, published this week in Nature Biotechnology, promises to be broadly applicable to identifying the genes that contribute to other types of cancer.

Although many of the key genes or sets of genes mutated in cancer cells have been identified, the search continues for mutations in culprit genes specific to a particular type of cancer?such as lung, breast or liver cancer. David Largaespada and colleagues previously demonstrated that mice engineered to express a jumping gene or 'transposon' develop tumors whenever the jumping gene lands in or near a cancer gene. They now fine-tune the system to disrupt genes only in certain cells. By restricting the transposon's movement to mouse liver cells, they can track its path in liver tumors to identify 19 genes also shown to often be defective in human liver cancers.

This strategy will augment other efforts to profile different types of human cancer, such as tumors of the brain, pancreas and colon. Ultimately, it could open the way for more effective cancer therapies.