Imagine a 60-year-old man recuperating at home after prostate cancer surgery, drawing comfort from the aged golden retriever beside him. This man might know that a few years ago the director of the National Cancer Institute issued a challenge to cancer re?searchers, urging them to find ways to "eliminate the suffering and death caused by cancer by 2015." What he probably does not realize, though, is that the pet at his side could be an important player in that effort.

Reaching the ambitious Cancer 2015 goal will require the application of everything in investigators' tool kits, including an openness to new ideas. Despite an unprecedented surge in researchers' understanding of what cancer cells can do, the translation of this knowledge into saving lives has been unacceptably slow. Investigators have discovered many drugs that cure artificially induced cancers in rodents, but when the substances move into human trials, they usually have rough sledding. The rodent models called on to mimic human cancers are just not measuring up. If we are going to beat cancer, we need a new path to progress.