Olive Leaf Extract Health-Promoting and Anti-Tumor Properties: An Adjunct Therapy in Pediatric Oncology?

Modern scientific research increasingly views olive leaf extract (OLE) not merely as a simple supplement, but as a sophisticated chemical orchestra where a wide array of phytochemicals works in natural harmony to provide therapeutic benefits. While olive oil is the most famous product of the Olea europaea tree, it is important to emphasize that the leaves are actually a far richer and more concentrated reservoir of bioactive molecules, often containing phenolic levels several times higher than those found in the fruit or oil. This whole plant extract often proves more biologically effective than isolated compounds because its components target multiple cellular pathways simultaneously. Many beneficial effects have been ascribed to OLE including anti-inflammatory, anti-oxidant, anti-microbial, anti-viral, neuroprotective, and anti-tumoral effects. In this review, we focused on the latter activity, especially in the field of pediatric tumors such as acute leukemias and neuroblastoma. This issue was discussed starting from the definition of OLE and its components describing the main biological activities, passing through the OLE roles on the immune system, moving on to the anti-cancer functions, and ending with future perspectives.