Scientific evidence suggests beneficial effects of olive oil compounds traditionally found within the Mediterranean diet. The health benefits of such diet include protection against a wide range of diseases including cardiovascular diseases and cancers. One of the well-known compound present within olive oil is called omega-9 mono-unsaturated oleic acid (OA). In this study, we explored if the OA compound can be involved in stimulating the production of molecules that suppress brain cancer. The most common and malignant cancers of the brain are called Glioblastoma multiforme. The median survival of patients with a glioblastoma is very low and even with the most extensive treatment, they survive for only about 15 months.
For years now scientists have been studying the role of small RNAs in regulation of gene expression. There are hundreds of small RNA molecules and one of them is called as miR-7. This particular one has been shown to have cancer suppressive properties. It does so by targeting oncogenes. Oncogenes are genes which, in certain circumstances, can transform a cell into a cancer cell.
miR-7 has been shown to target an oncogene called EGFR (Epidermal Growth Factor Receptor), which is responsible for accelerating cancer growth. Scientists have observed that low levels of miR-7 have been linked with poor survival of patients with glioblastoma. Our team previously found certain proteins (HuR and MSI2) that can suppress the production of miR-7 and this in turn speculatively lead to higher death rates of patients with glioblastoma.
Methods and findings
We reasoned that if we could inhibit the action of the proteins- HuR and MSI2 and enhance the production of miR-7, maybe this could lead to increased survival of glioblastoma patients. In our study, we found that OA interfered with binding of HuR and MSI2 and resulted in increased production of cancer-suppressing miR-7 molecule. We have performed a series of experiments in cell extracts and cultured cells in the lab to demonstrate that OA can directly influence the production of miR-7.
Our research revealed for the first time that the compound found in olive oil can modulate RNA processing events and hence may be implicated in keeping the cancer at bay.
Now we are planning to focus on establishing the specificity of OA in regulating miR-7 production in a human glioblastoma cell model. Another interesting avenue will be to use mouse models to evaluate if consumption of olive oil increases miR-7 production in the brain. Altogether, we are extremely excited about our finding as it provides an entry point towards designing potential drug molecules that target miR-7 deficiency in cancer.
Research Article: Oleic Acid Induces MiR-7 Processing through Remodeling of Pri-MiR-7/Protein Complex. Journal of Molecular Biology. Volume 429, Issue 11, 2 June 2017, Pages 1638–1649.