A new study in cancer cell lines has found that the gamma-linolenic acid (GLA)--a polyunsaturated fatty acid found in several plant oils that has been used as an herbal medicine--affects the expression of the Her-2/neu oncogene. The study found that GLA inhibited Her-2/neu in a different way from that of trastuzumab (Herceptin), the monoclonal antibody approved for treatment of breast cancer patients with high levels of Her-2/neu.
The Her-2/neu oncogene is involved in the development of many types of cancer, including breast cancer. Javier A. Menendez, Ph.D., of Evanston Northwestern Healthcare Research Institute in Illinois, and colleagues found that treating cancer cell lines that overexpressed Her-2/neu with GLA reduced Her-2/neu protein levels. In addition, GLA exposure in these cell lines led to a decrease in Her-2/neu promoter activity and an increase in the levels of a transcriptional repressor of Her-2/neu.
The researchers also found that treating the cancer cell lines with both GLA and trastuzumab led to a synergistic increase in apoptosis and reduced cell growth.
The Journal of the National Cancer Institute is published by Oxford University Press and is not affiliated with the National Cancer Institute. Visit the Journal online at jncicancerspectrum.oxfordjournals.org.