点击显示 收起
Nov. 1, 2005 -- Could oil from tiny seeds help bring a big, bad cancer gene to its knees?
Maybe, but it's going to take a lot more work to find out, according to a new study in The Journal of the National Cancer Institute.
Keep that in mind before you delve into the details of the study, which involved cancer cells, not people or animals.
The scientists included Javier Menendez, PhD, and Ruth Lupu, PhD.
Menendez is a research assistant professor of medicine at Northwestern University's Feinberg School of Medicine. Lupu is a professor of medicine at Northwestern University and a researcher at Northwestern's Robert H. Lurie Comprehensive Cancer Center.
In One Corner: A Cancer Gene
The study focuses on the Her-2/neu cancer gene. It's involved in some (but not all) cancers, including more than a fifth of breast cancers.
The gene has been linked to particularly aggressive breast tumors, and cancer patients with this gene often have a poor prognosis, Lupu says in a news release.
The gene orders the overproduction of a protein called the Her-2/neu protein. Some cancer cells grow when exposed to Her-2/neu protein.
In the Other Corner: A Seed Oil
The researchers tested gamma-linolenic acid against cancer cells with the Her-2/neu gene.
Gamma-linolenic acid, or "GLA," is found in oil from the seeds of evening primrose, borage, and black currant. Some studies have suggested that GLA might target cancer cells without affecting healthy cells, write the scientists.
Round One: GLA vs. the Gene
The researchers studied human breast cancer cells with the Her-2/neu gene. They exposed some of those cells to GLA for 48 hours. For comparison, they left other cancer cells alone.
Afterward, they checked the surfaces of the cells for the Her-2/neu protein.
The GLA-exposed cancer cells showed "substantially" less of that protein than the cancer cells that hadn't been exposed to GLA, the researchers write.
Round Two: The Rematch
Next, the researchers exposed more breast cancer cells to various doses of GLA for 48 hours. Then, they poked around in part of those cells' genetic material.
The higher the GLA dose, the higher the odds that those cells didn't copy the Her-2/neu gene. GLA may have been a stumbling block in the copying of that cancer gene.
Round Three: Tag-Team With Cancer Drug
GLA has been shown to make cells more sensitive to the effects of some cancer drugs, write the researchers.
So they teamed GLA with the breast cancer drug Herceptin in some lab tests. Herceptin targets breast cancer cells that grow when exposed to the Her-2/neu protein.
The combination made breast cancer cells 30 to 40 times more sensitive to Herceptin. That was a significant difference, write the researchers.
GLA and Herceptin work differently on Her-2/neu, says Menendez in a news release.
Not a Knockout
The researchers call for more studies of GLA and cancers with the Her-2/neu gene. But they caution that extensive preliminary studies are necessary before GLA can be tested in clinical trials.
In January, the same team of researchers reported in the Annals of Oncology that a . That study, too, was based on lab tests of breast cancer cells.
SOURCES: Menendez, J. Journal of the National Cancer Institute, Nov. 2, 2005; vol 97: pp 1611-1615. WebMD Medical Reference from Healthwise: "Herceptin." News release, Northwestern University.