Us Launches Cancer Gene Mapping Project

WASHINGTON (Reuters) - U.S. government researchers launched on Tuesday a pilot project to find all the genetic changes that cause cancer and hope it can open a whole new world of targeted cancer therapy.

They hope to lay the groundwork for replicating the successes of a few targeted cancer therapies such as Genentech Inc's Herceptin, useful against one type of breast cancer, and Novartis' Gleevec, a drug that revolutionized treatment of chronic myeloid leukemia.

Scientists know that cancer is a genetic disease, caused by mutations or other changes in the DNA of cells. But no one has done a systematic analysis of all the mutations in various tumors.

The Cancer Genome Atlas project launched by the National Cancer Institute and the National Human Genome Research Institute will try to make a start.

The word "cancer" describes a range of at least 200 different diseases, and even "lung cancer" or "breast cancer" are catchall terms for tumors that arise because of different genetic mistakes.

Cancer is the second leading killer in most industrialized countries, after heart disease, and about 60 percent of patients are alive five years after diagnosis.

"This cancer genome atlas project is all about the progress that is necessary for us to make cancer a chronic and manageable condition that no longer causes the suffering and death that we see all around us," Dr. Andrew von Eschenbach, director of the National Cancer Institute who is currently also acting commissioner of the U.S. Food and Drug Administration, told a news conference.

STARTING OUT SMALL

The researchers are not yet sure which cancers they will start with but say it will be a small number, perhaps two or three. They will seek hundreds of samples from hundreds of patients with the selected tumor types and then use the human genome map made at NHGRI to try and find all the changes that mark cancer.

Several cancer-causing mutations, called oncogenes, are known already.

Some of the best known are the BRCA1 and BRCA2 breast cancer genes, also implicated in some cases of ovarian cancer, the p53 gene involved in many different tumors, and the EGFR gene targeted by AstraZeneca Plc's Iressa and Genentech and OSI Pharmaceutical's Tarceva, which have remarkable effects against a small percentage of patients with lung cancer.

There must be many more, the researchers said.

"We are dealing with the tip of the iceberg," said Dr. Ron DePinho of Harvard Medical School and the Dana Farber Cancer Institute in Boston. "There are a staggering number of genetic alterations that occur."

DePinho said the project would "liberate the cancer community" from having to track down each gene one by one, and instead concentrate on what those genes do and which ones make the best targets for drugs.

"I think this is a turning point in biomedical research and I think it is a turning point for medicine," said Anna Barker, deputy head of the NCI.

It could be some drugs already used against one form of cancer may be useful against others. Gene testing will allow doctors to figure that out right away, instead of taking the trial-and-error approach now often used.

"We have in our armamentarium quite a few drugs. Only one of them can give you an advantage but not necessarily full survival," said National Institutes of Health Director Dr. Elias Zerhouni.

Identifying the precise genetic mutations in a tumor might make it easier to use intelligently designed combinations of drugs, Zerhouni said.