last updated April 2013
Raising the screen on cancer genes
Random insertion of small chunks of DNA into the mouse genome reveals genes that could be linked to human pancreatic cancer
The identification of genes that cause cancer in mice when their expression is altered could inform the discovery of tumor-inducing genes in humans. Now, using a genetic screening tool in which small bits of DNA randomly insert themselves all over the mouse genome within pancreatic cells, an international team of researchers led by Neal Copeland at the Institute of Molecular and Cell Biology in Singapore has identified genes that drive pancreatic cancer in mice1.
When small chunks of DNA called transposons insert themselves into the genome, activation or inactivation of a gene can result. Overactivation of a gene that drives tumor induction can lead to cancer, as can inactivation of a gene that suppresses cancer. By examining the location of transposon insertion within genes, the researchers determined that gene inactivation was more likely to induce pancreatic tumors in the mice than gene activation. They argue, therefore, that most of the genes they identified were likely to suppress tumor formation.
Using their genetic screen, Copeland and colleagues identified a number of gene pairs that tended to be disrupted together within mouse tumors. They also found that some of the genes that were disrupted in the mouse tumors were also mutated within human pancreatic cancer, or were associated with lower patient survival.