The discovery of a tumor-protecting role for a fatty acid found in fish oil has sparked debate about the product’s safety.
Emile Voest, a professor of medical oncology and medical director of The Netherlands Cancer Institute, has spent his career studying the tumor microenvironment—cancer’s cellular backdrop, implicated in everything from a tumor’s structural support to its protection from the immune system and its resistance to cancer-treating drugs.
But it came as some surprise, Voest says, when, in the mid-2000s, he and his colleagues identified two obscure polyunsaturated fatty acids—16:4(n-3) and KHT—that seemed to induce chemoresistance in tumor-bearing mice. “It was not what I was expecting at all,” says Voest. “We had no clue what fatty acids were [or] how they worked.”
The researchers found that human mesenchymal stem cells (multipotent stromal cells already implicated in drug resistance) injected into tumor-bearing mice began secreting these fatty acids when the animals were administered cisplatin—a platinum-based drug used to treat various types of cancer. These platinum-induced fatty acids (PIFAs) had no effect on tumor growth, but neutralized the cytotoxic effects of cisplatin on tumor cells, hinting at a possible mechanism of chemoresistance in human patients receiving platinum-based therapies.