Brain Cancer Could be Prevented with Olive Oil Compound

    The health benefits of olive oil are wide-ranging; studies have linked the fat to reduced risk of obesity and heart disease, as well as cognitive improvements. Now, new research suggests that olive oil may also help to prevent brain cancer.

    Scientists at the University of Edinburgh caution that we’re a long way from knowing whether brain cancer can be prevented by pouring olive oil on your dinner plate, but they do seem encouraged that olive oil’s main ingredient, oleic acid, can suppress the function of cancer-causing genes when it is “fed” to cells in a petri dish.

    These scientists report that oleic acid can influence the binding of proteins containing RNA recognition motifs. For example, oleic acid can prevent an RNA-binding protein from interfering with the production of a primary microRNA (pri-miR), called pri-miR-7, which helps prevent the formation of tumors.

    The findings appeared June 2 in the Journal of Molecular Biology, in a paper entitled “Oleic Acid Induces MiR-7 Processing through Remodeling of Pri-MiR-7/Protein Complex.” According to the article’s authors, the findings suggest that studies of oleic acid could lead to new tools for studying RNA processing. Moreover, such studies could lead to the development of small molecules capable of targeting the miR-7 biogenesis pathway.

    “We show that oleic acid (OA) inhibits the binding of proteins containing RNA recognition motifs (RRMs) to the conserved terminal loop of pri-miR-7,” wrote the article’s authors. “Using electrophoretic mobility shift assays in HeLa cell extracts, we show that OA treatment disrupts pre-miR/protein complexes.”

    The pre-miR/protein complexes involve Hu antigen R (HuR)-mediated binding of Musashi homolog2 (MSI2) to the conserved terminal loop of pri-miR-7, a process that regulates the levels of brain-enriched miR-7 formation in a tissue-specific manner. Disruption of these complexes, the authors indicated, rescues in vitro processing of pri-miR-7, which is otherwise blocked by HuR and MSI2 proteins.

    Curiously, oleic acid showed opposite effects on the in vitro processing of the pri-miR-7 and another pri-miR, pri-miR-16, which has been used in many studies as an internal control, as it is ubiquitously expressed and its level remains relatively stable during the cell life cycle.

    “This indicates various requirements for the trans-acting protein factors that play positive and negative roles in the control of their processing,” the article’s authors noted, adding the speculation that oleic acid may inhibit the binding of other RRM-containing protein/s necessary for miR-16 processing. “Further studies need to be performed to unravel the specific proteins necessary for the regulation of miR-16 biogenesis.”

    The study team, led by Gracjan Michlewski, Ph.D., says it is too soon to say whether dietary consumption of olive oil may help prevent brain cancer. The team’s findings, however, point toward possible therapies based on the oil to prevent brain cancer from occurring.

    “While we cannot yet say that olive oil in the diet helps prevent brain cancer,” said Dr. Michlewski, “our findings do suggest that oleic acid can support the production of tumor-suppressing molecules in cells grown in the lab. Further studies could help determine the role that olive oil might have in brain health.”