February 8, 2012

Personalizing Cancer Therapy

(Ivanhoe Newswire)-- When fighting tumors it is essential doctors target the metabolic reactions that fuel their growth. A new study shows that a one-size-fits-all metabolism-specific cancer therapy will not fight every type of cancer.

Researchers say that metabolic profiling will be imperative for defining each type of cancer and choosing the best treatment option for a patient.

Their evidence comes from observing mice that exhibit how tumors metabolic profiles vary. The variations depended on the genes behind a certain cancer and on the tissue of origin.

"Cancer research is dominated now by genomics and the hope that genetic fingerprints will allow us to guide therapy,” J. Michael Bishop, University of California, San Francisco, was quoted as saying. "The issue is whether that is sufficient. We argue that it isn't because metabolic changes are complex and hard to predict. You may need to have the metabolome as well as the genome."

Just as a cancer genome refers to a full set of genes, the metabolome refers to the complete set of metabolites in a particular tumor.

The team led by Bishop and Mariia Yuneva was curious as to how metabolism might vary with the underlying genetic causes of cancer.

The team found that in mice, liver cancers driven by different cancer-causing genes showed differences in the metabolism of two major nutrients: glucose and glutamine.

"Our work shows that different tumors can have very different metabolisms," Yuneva was quoted as saying. "You can't generalize."

Bishop and Yuneva say their findings also highlight glutamine metabolism as a potential new target for therapy in some tumors, noting that the focus has been primarily on glucose metabolism. They also found that the data shows a form of a glutaminase enzyme typically found in kidney cells is also observed in cancerous liver cells. Meaning there may be a way to target the metabolism of the cancer without damaging normal liver tissue.
"We shouldn't lose sight of the rather immediate therapeutic potential," Bishop said.

The researchers plan to continue researching metabolic variations in mice. They say it will be important to document the metabolic variation in a more in-depth, human setting.

SOURCE: Cell Metabolism, February 7, 2012