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

DATE: FRIDAY, April 8, 1994                   TAG: 9404080186
SECTION: VIRGINIA                    PAGE: A-5   EDITION: METRO 
SOURCE: Associated Press
DATELINE: SAN FRANCISCO                                LENGTH: Medium

STUDY FINDS AIDS CAUSES CANCER

Researchers have found that the AIDS virus directly causes cancer, and the discovery offers a possibility of better treatment for both diseases. It also raises doubts about the safety of some new forms of gene therapy.

The results, being announced today, could lead to safer ways to treat certain forms of cancer in AIDS victims, said the study's authors, University of California, San Francisco, Drs. Michael McGrath and Bruce Shiramizu.

"This is the first direct evidence that we have a human virus causing cancer through some mechanism - not just indirectly by immunosuppression," McGrath said.

Cancers, including lymphoma and Kaposi's sarcoma, long have been associated with AIDS. But most researchers have thought the cancers were opportunistic, taking advantage of AIDS' weakening of the immune system rather than being caused by the virus itself.

The study, however, found that when the AIDS virus inserted its genetic material into a cell's DNA, it apparently switched on a nearby cancer-causing gene, starting up a less common variety of lymphoma called non-B-cell lymphoma.

The scientists spent two years reviewing 30 lymphoma cases, and found four in which the AIDS virus inserted itself into the same spot in a cell's DNA. McGrath said the researchers now have additional examples, and estimated that up to a third of non-B-cell lymphomas in AIDS patients show similar results.

The study is to be published April 15 in Cancer Research, the journal of the American Association for Cancer Research.

Dr. William A. Blattner, chief of the viral epidemiology branch of the National Cancer Institute, hailed the finding as an important step in understanding how a retrovirus, the class of virus that includes the AIDS virus, can cause cancer.

"This has been seen in animal retrovirus, but it's the first example of an insertional retroviral situation in man," he said.

Dr. Dawn Willis, a virologist and scientific program director for the American Cancer Society, called the study "a very exciting finding."

She said the link between AIDS and cancer always was considered indirect because no one had ever found HIV, the AIDS virus, in a cancer cell before. The discovery could suggest research in tracing the role of viruses in other cancers.

But the study also casts a cloud over the goal of creating an AIDS vaccine from a form of the live HIV virus. Scientists fear such a vaccine could trigger cancer genes while halting AIDS.

\ KEY FINDINGS\ IN RECENT AIDS RESEARCH\ \ In two years of examining 30 non-B-cell lymphoma cases in AIDS patients, investigators found four in which the virus directly inserted itself into the cancer cell's DNA.\ \ The insertion site was the same in all cases, and was close to a known cancer-causing oncogene.\ \ Based on the data, researchers say as many as one-third of non-B-cell lymphomas in AIDS patients may be directly caused by the virus.\ \ The link raises questions about future AIDS vaccines that use the live virus, and for gene therapy employing retroviruses.

by CNB