U.S. to Begin Mapping Cancerous Tumor Cells

In a bold but uncertain bid to spur cancer treatment, federal medical researchers announced a $100-million project Tuesday to begin cataloging the disease's molecular underpinnings.

The Cancer Genome Atlas, as the project is called, will start as a three-year pilot program to identify the genes behind two or three types of cancerous tumors. If the research proves promising and affordable, it would be expanded to study thousands of cancerous tumors.

Describing the effort as potentially "revolutionary," officials at the National Institutes of Health said the resulting knowledge could lead to the development of more effective cancer drugs and therapies.

"This is really the beginning of an era," said Dr. Elias A. Zerhouni, director of the NIH, the government's main medical research arm and a distributor of funding. "What I think we will see is an acceleration of discovery."

Often referred to as a single disease, cancer is a collection of more than 200. Cancers develop, scientists believe, after genetic changes cause cells to mutate and grow wildly.

The cancer project, NIH officials said, would find the common features underlying the genetic malfunctions — probably not a single glitch causing various cancerous cells to flourish, but a set of glitches that each lead to a number of diseases.

"It will be an important step in our understanding of the genetic components of cancer and the genetic susceptibilities of people affected by cancer," said Dr. Andrew C. von Eschenbach, director of the National Cancer Institute and acting head of the Food and Drug Administration.

In 2003, scientists finished mapping the human genome, the genetic code that guides a body's functions and characteristics. Sequencing cancer genes is a natural follow-up, as researchers can use the blueprint of normal human DNA to identify cancer genes.

Supporters of the cancer project contend that the vast diversity of cancer genes requires NIH involvement. They say more effective treatments can't be developed without the better understanding that sequencing cancer genes would provide.

"The more we learn about cancer at the molecular level, the more chance we have of being successful in treating cancer," said Dr. Bob Strausberg, vice president for human genomic medicine at the J. Craig Venter Institute in Rockville, Md., founded by the scientist who raced the government to be first to define the human genetic code.

The sequencing of cancer genes is challenging, and the work is costly. Because cancer causes the cells to mutate, each tumor cell has its own genome, so mapping every tumor would be equivalent to undertaking scores of human genome projects — 12,500 by one estimate.

Researchers must review many genes before distinguishing those that play important roles in causing mutations.

Another obstacle is that no two cells in a malignant tumor may be identical. So successful sequencing of some cancer genes might miss others. If a missed gene plays a key role in causing malignancy, treatment would suffer.

For that reason, Dr. Garth R. Anderson, a cancer geneticist at the Roswell Park Cancer Institute in Buffalo, N.Y., criticized the project for taking money from what he said was more worthwhile research promising early diagnosis of tumors and more lasting treatments.



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