GLA May Help Cancer Drugs Work More Efficiently

by | Aug 8, 2008 | 2005, Alternative Therapies, Cancer, Fats and Oils - General

Written by Susan Sweeny Johnson, PhD, Biochem. GLA treatment combined with tastuzumab, an anti cancer drug, increases the effectiveness of tastuzumab by 30-40 fold and works synergistically with other anticancer drugs like paclitaxel, docetaxel and vinorebine as well as antiestrogens, tamoxifen and ICI 182,780.

GLA (Gamma Linoleic Acid) is an omega-6 fatty acid found in evening primrose, borage and black currant oil that has been shown to promote good health on many levels. Now a number of studies have shown that GLA selectively kills cancer cells in vitro. (1-8) Researchers recently looked at the effects of GLA on a specific type of cancer, Her-2/neu positive, and tried to determine how it kills these cells.

Her-2/neu is a protein that is known to promote cancer cell growth. Although it is made in normal cells, in some cancer cells it is made in very large quantities. If a cancer tests positive for excess Her-2/neu, it is routinely treated with an antibody against this protein which will promote death of the cancer cells. (13)

In this study, two Her-2/neu positive cell lines, one breast and one ovarian cancer were treated with GLA alone.  The amount of Her-2/neu protein was significantly reduced in both types of cells. The amount of Her-2/neu mRNA was also reduced. Further experiments showed that GLA gets in the way of the signal to turn on Her-2/neu mRNA production in the cell (the promoter region).

Next, GLA treatment was combined with the commonly used antibody to Her-2/neu, trastuzumab. One breast cancer cell line and one ovarian cancer cell line were tested for apoptosis (cell death). In the breast cell line, 5% of cells died (as compared to no treatment) with GLA, 13% died with trastuzumab and 38% with GLA and tastuzumab used together. In the ovarian cell line, 3% died with GLA, 11% with trastuzumab and 43% with both. Use of GLA with trastuzumab increased its effectiveness 30-40 fold.

Other studies show that GLA works synergistically with other anticancer drugs like paclitaxel, docetaxel and vinorebine as well as antiestrogens, tamoxifen and ICI 182,780. (9-12)

Synergism between GLA and trastuzumab is good news for Her-2/neu positive cancer patients and may provide more effective treatment of their cancers. Taking GLA alone may help slow the growth of cancer cells.

Source: Zhang, Lisha, Ching-jer Chang, Sarah S. Bacus, and Mien-Chie Hung. “Suppressed transformation and induced differentiation of HER-2/neu-overexpressing breast cancer cells by emodin.” Cancer research 55, no. 17 (1995): 3890-3896.

©1995 American Association for Cancer Research

Posted August 8, 2008.

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