A new study has found that a type of fat commonly found in seed oils and animal products may help a dangerous form of breast cancer grow faster.
The fat, called linoleic acid, is an omega-6 fatty acid found in soybean oil, safflower oil, pork, eggs, and many processed foods.
Researchers at Weill Cornell Medicine discovered that linoleic acid can speed up the growth of triple-negative breast cancer (TNBC) — a fast-growing and hard-to-treat type of breast cancer.
Their findings were published on March 14 in the journal Science.
Triple-negative breast cancer is different from other types of breast cancer because it doesn’t have the hormone receptors (estrogen, progesterone, or HER2) that most treatments target.
Because of this, it’s harder to treat and more aggressive.
In this study, scientists found that linoleic acid activates a key growth pathway in cancer cells called mTORC1. This pathway helps cancer cells grow and divide.
The researchers discovered that linoleic acid binds to a protein called FABP5, which is found in high amounts in triple-negative breast cancer cells. This combination turns on the mTORC1 pathway and promotes cancer growth.
To test this, the researchers fed mice (that had triple-negative breast cancer) a diet high in linoleic acid. These mice had higher levels of FABP5, more mTORC1 activity, and faster tumor growth. The same pattern was seen in blood and tumor samples from patients recently diagnosed with triple-negative breast cancer — they had higher levels of both linoleic acid and FABP5.
This study is the first to show exactly how a common dietary fat can make certain cancers grow faster.
The researchers believe that FABP5 could be used as a biomarker, helping doctors give more personalized advice to patients with triple-negative breast cancer — including diet recommendations or new treatments that block this pathway.
Although linoleic acid is an essential fat that the body needs in small amounts, its levels have gone up dramatically in Western diets over the past 70 years due to the increased use of seed oils in processed and fried foods.
The research team also found that the same fat-driven pathway might affect other types of cancer, such as some prostate cancers, and may even play a role in obesity and diabetes. More research is underway to better understand this.
For now, the study offers new hope for targeted strategies — possibly including dietary changes — to slow the growth of aggressive cancers like triple-negative breast cancer.
If you care about breast cancer, please read studies about a major cause of deadly breast cancer, and this daily vitamin is critical to cancer prevention.
For more information about cancer, please see recent studies that new cancer treatment could reawaken the immune system, and results showing vitamin D can cut cancer death risk.
Source: Cornell University.
