New research in mice suggests that a compound commonly found in palm oil may promote cancer metastasis. Taylor Weidman/Bloomberg via Getty ImagesFatty acids are essential for health, but altered metabolism and absorption of fatty acids is a hallmark of metastasis.Saturated fatty acids such as palmitic acid, found in palm oil, can promote the expression of genes associated with tumor metastasis.Cancer cells have a “memory” of exposure to palmitic acid and remain highly disseminated.
Fatty acids (FAs) are the main building blocks of fat in our bodies and the food we eat. They can serve as fuel for metabolic pathways.
There are three main types of FA, categorized according to their chemistry:
monounsaturated FAs, which are associated with a reduced risk of coronary heart disease polyunsaturated FAs, which are protective against the risk of dementia and coronary heart disease saturated FAs and trans fats, which are associated with an increased risk of coronary heart disease
More than 20 types of FAs are found in foods, and according to the American Heart Association (AHA), “For good health, the majority of the fats you eat should be monounsaturated or polyunsaturated,” as opposed to saturated or trans fats, which people need to eat. avoid.
Cancer cells can rewire their metabolism to produce the energy needed for their growth and eventual survival. FA metabolism plays an important role in providing energy and macromolecules for cancer development.
A study has now shown that palmitic acid, an FA found in palm oil, a common ingredient in cakes, cookies and chocolate, may increase the metastasis or spread of cancer.
According to a previous study, from 2019, more than 65% of deaths from solid tumor cancer had metastases as a recorded contributing cause. Metastasis occurs when cancer cells move away from the main tumor mass and enter the blood or lymphatics, allowing them to travel and grow into tumors in other parts of the body.
The new study, published in Nature, sought to understand whether different FAs cause changes that increase the risk of cancer metastasis — and if so, how?
dr. Salvador Aznar-Benitah, of the Institute for Research in Biomedicine, in Barcelona, led the study. The team exposed human oral and skin cancer cells to three dietary FAs: palmitic acid, oleic acid and linoleic acid. After 4 days of exposure, the researchers transferred the cells to where they would belong in mice. They were fed a typical diet.
None of the FAs promoted cancer formation, but palmitic acid, the major saturated FA in palm oil, promoted the increased expression of genes associated with metastasis and the size of existing metastatic lesions.
The effects of FAs may differ depending on the tumor type. For example, in this study, oleic acid inhibited the spread of both mouth and skin cancers, but previous studies showed that it promoted cervical cancer.
In a separate experiment, the group tested the “memory” of cells exposed to palmitic acid. They exposed human oral cancer cells to palmitic acid for 4 days and then grew the cells for another 14 days without palmitic acid. The team then implanted the cells, as before, in mice fed a typical diet.
The researchers found that the tumor cells exposed to palmitic acid were still highly spreading.
According to the authors of the study, this “memory” is associated with epigenetic changes — reversible changes, caused by environmental factors, that alter the way genes work without changing the DNA sequence.
dr. Aznar-Benitah notes that a study completed in 2017 showed an increased risk of metastasis, but the mechanism behind this was unknown. “In this study, we detail the process and reveal the involvement of a metastatic capacity ‘memory’ factor, and point out a therapeutic approach to reverse it. This is promising.”
The senior study author also mentions his hopes to move the technology into clinical trials. “If everything goes as planned, we can begin the first clinical trial in a few years.”
Prof. dr. Ali Shilatifard, co-author of the study and director of the Simpson Querrey Institute for Epigenetics, says: “Control of metastasis is the last frontier for cancer therapy,” indicating the findings could lead to a generation of new therapies targeting the FA- metabolism.
Worldwide Cancer Research chief executive, Dr. Helen Rippon, echoed these thoughts. It’s worth noting that worldwide cancer research funded the study.
dr. Rippon tweeted: “Metastasis is such a gap in our understanding of #cancer, but it is the cause of cancer deaths. Preventing/limiting metastasis could save millions of lives.” She explained this in an interview, saying:
“This discovery is a major breakthrough in our understanding of how diet and cancer are related, and perhaps more importantly, how we can use this knowledge to initiate new treatments for cancer. [….] We are all very excited to see the results of this clinical trial and the future impact these findings may have on people with metastatic cancer.”