By Craig Weatherby
Breast cancer is the most common form of cancer in women worldwide.
Behaviors appear to affect cancer risk, with about one-third of cases linked to poor diet and lifestyle choices.
And growing evidence suggests that early exposure to omega-3 fatty acids from fish (DHA and EPA) may curb breast cancer risks (MacLennan M et al. 2010).
For more on that, see “Omega-3s: Start ‘em Early to Stop Breast Cancer”, and our “Foods and breast risk” sidebar.
Conversely, diets high in omega-6 fats from vegetable oils appear to raise the risk … see “Breast Cancer and Omega-3s: More Encouraging Evidence” and “Breast Cancer Tied to Omega Imbalance … Again”.
Breast cancers differ in dangerousness
Breast cancers fall into two major classes ... both dangerous, but one inspires dread.
Tumors that feature cells with estrogen receptors are call “ER-positive”. They’re potentially deadly, but often treatable or curable.
The one-third of breast tumors that lack estrogen receptors are called “ER-negative”. These aggressive cancers resist treatment and have poor prognoses.
About 15 percent of ER-negative cancers are “triple-negative” tumors, whose cells lack receptors for any of the three hormones that fuel ER-positive cancers: estrogen (ER), progesterone (PR), and human epidermal growth factor.
Based on very preliminary research, targeted nutrition may help prevent and/or treat triple-negative tumors. For example, see “Vitamin D Lack Linked to Killer Breast Cancer” and “Does Coffee Curb Breast Cancer?”.
Now, a cell study suggests that omega-3 fatty acids from fish may be allies against these tough-to-treat breast tumors.
Foods and breast risk
We’ve covered a good deal of the research into the effects of diet on breast cancer risk:
Toughest tumors may respond to omega-3s
Scientists from Fox Chase Cancer Center set out to see whether fish-source omega-3s would work better or worse against triple-negative breast cancer cells, versus cells from other types of the disease (Pogash T et al 2013).
Specifically, they wanted to test whether omega-3s from fish (EPA and DHA) and their metabolites would slow or stop the creation of new cells (proliferation) in different kinds of tumors.
(When omega-3s get absorbed into a cancer cell, they’re broken down into smaller molecules called metabolites.)
So the Fox team tested the effect of omega-3 EPA and DHA and their metabolites on three ER-positive cell lines and seven triple-negative cell lines.
The omega-3s worked against all types of cancer cells. But as the Fox Center said, the impact of omega-3s was “dramatically more pronounced” against triple-negative tumor cells.
Encouragingly, fish-derived omega-3s curbed cell-proliferation in triple-negative tumors by up to 90 percent.
In addition, omega-3 metabolites cut the triple-negative breast cancer cells’ ability to move by 20 to 60 percent.
This study is part of a collaboration between Fox Chase Cancer Center and Pennsylvania State University under a five-year grant awarded by the Komen Foundation.
Andrea Manni, M.D., leader of the Pennsylvania State University team, is currently testing the effects of omega-3s and its metabolites on triple-negative breast cancer in rodents.
We’ll let you know how those studies turn out.
Positive results may lead to human clinical trials … the only way to be certain that omega-3s can help fight triple-negative breast cancers.
- Cazzaniga M, Bonanni B. Prevention of ER-negative breast cancer: where do we stand? Eur J Cancer Prev. 2012 Mar;21(2):171-81. doi: 10.1097/CEJ.0b013e32834c9c26. Review.
- Fox Chase Cancer Center (FCCC). Omega-3 Fatty Acids More Effective at Inhibiting Growth of Triple-Negative Breast Cancer than of Luminal Breast Cancers. April 9, 2013. Accessed at https://www.fccc.edu/information/news/press-releases/2013/2013-04-09-aacr-omega3-fatty-acids.html
- Gierach GL, Burke A, Anderson WF. Epidemiology of triple negative breast cancers. Breast Dis. 2010;32(1-2):5-24. doi: 10.3233/BD-2010-0319.
- Huynh KT, Chong KK, Greenberg ES, Hoon DS. Epigenetics of estrogen receptor-negative primary breast cancer. Expert Rev Mol Diagn. 2012 May;12(4):371-82. doi: 10.1586/erm.12.26. Review.
- Pogash T et al. Polyunsaturated omega-3 fatty acids and their metabolites preferentially inhibit cell proliferation and motility in triple negative over luminal breast cancer cells. American Association for Cancer Research (AACR) Annual Meeting 2013. Presentation Abstract Number 2600. PO.PR01.01. Epidemiology / Molecular Targets. Tuesday, Apr 9. 2600/30 - Accessed at http://www.abstractsonline.com
- Putti TC, El-Rehim DM, Rakha EA, Paish CE, Lee AH, Pinder SE, Ellis IO. Estrogen receptor-negative breast carcinomas: a review of morphology and immunophenotypical analysis. Mod Pathol. 2005 Jan;18(1):26-35.
- Secreto G, Zumoff B. Role of androgen excess in the development of estrogen receptor-positive and estrogen receptor-negative breast cancer. Anticancer Res. 2012 Aug;32(8):3223-8. Review.