
                         Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: WEDNESDAY, March 28, 1990                   TAG: 9003280488
SECTION: NATIONAL/INTERNATIONAL                    PAGE: A/3   EDITION: EVENING 
SOURCE: Associated Press
DATELINE: DAYTONA BEACH, FLA.,                                LENGTH: Medium

STUDY SUGGESTS BODY ATTACKS CANCERS CELLS

Scientists have found evidence that people with breast or pancreatic cancer naturally mount an attack on their tumors, raising hopes for a treatment that might make the reaction more powerful.

Patients with those diseases produce tumor-killing white blood cells that healthy people lack, researcher Olivera Finn said.

She and colleagues have identified a substance on cancer cells that appears to be the target of the attack, and they hope that a vaccine-like treatment might boost the anti-cancer response, she said Tuesday.

Finn, an assistant professor in the department of microbiology and immunology at the Duke University Medical Center in Durham, N.C., spoke at a science writers seminar sponsored by the American Cancer Society.

More than 150,000 cases of breast cancer and 28,000 cases of pancreatic cancer are expected to be diagnosed this year.

Finn, with graduate students Donna Barnd and Keith Jerome, found that patients with either cancer produced immune system cells that could kill cancer cells while ignoring normal ones. That occurred in all 14 pancreatic cancer patients and all six breast cancer patients studied, Finn said.

Since no such cells could be found in healthy patients, they seem to come from a natural response to the tumors, she said.

The target of the killer cells was found to be epithelial cell mucin, which is found on the tumor cells, Finn said.

Tumors probably survive the attack by growing faster than killer cells can destroy them, she said. Or perhaps killer cells go after mucin that tumor cells secrete in large amounts into the bloodstream, instead of concentrating their attack on the tumor cells themselves.

A vaccine based on mucin might boost the immune system response and make it more effective against the cancer, she said.

The next step is to do large studies of patients with breast or pancreatic cancer to see how strong the natural immune system response is. A vaccine may be ready for testing within a few years, she said.

In another presentation, Patricia Steeg of the National Cancer Institute reported the discovery of a gene that appears to suppress a cancer cell's ability to spread within the body.

In several kinds of cancer, the more active the gene was, the less ability the cancer had to spread, she said.

Upcoming studies will see if the level of activity of the gene, called nm23, can predict the spreading behavior of breast, lung, bladder and prostate cancer cells, she said.

If the gene does suppress spreading, called metastasis, it may be useful as a tool to find drugs that can hinder that process, she said.

by CNB