Corrupt lifestyles and vices go hand in hand; each feeds the other. But even the worst miscreant needs customary societal amenities to get by. It's the same with cancer cells. While they rely on vices in the form of genetic mutations to wreak havoc, they must sustain their activity, and that requires equal parts vice and virtue.

According to a new study in the May 29 issue of Cell, cancer cells rely heavily on many normal proteins to deal with stress and maintain their deviant state. Researchers at Harvard Medical School and Brigham and Women's Hospital used a technique called RNA interference (RNAi) to dial down the production of thousands of proteins and determine which were required for cancer cell survival.

"Cancer cells actually leverage many genes that don't harbor mutations to maintain their malignant lifestyles," says first author and postdoctoral researcher Ji Luo. "These genes probably help them deal with the problems that develop as a result of the inappropriate presence of growth and survival signaling in tumor cells."

Being a cancer cell isn't easy. Think of all the DNA replication and protein production involved, not to mention the abnormal architecture of a tumor, which deprives cells of oxygen. Survival requires a complete kit of stress response tools.

"Researchers often characterize cancer cells as oncogene addicts, but they're just as reliant on normal genes that alleviate stress," explains senior author Stephen Elledge, a professor at HMS and Brigham and Women's Hospital. "These stress management genes deserve attention as potential therapeutic targets."

In recent years, the National Cancer Institute has supported an ambitious effort to understand the molecular basis of cancer by sequencing cancer genomes. Elledge and Luo note that this Cancer Genome Atlas project would miss the stress management genes.

"If these genes are intact, they won't stand out when you compare the DNA sequences of cancer cells with normal cells," says Luo.