Olive leaf extract impairs mitochondria by pro-oxidant activity in MDA-MB-231 and OVCAR-3 cancer cells

Area of Science:

• Oncology
• Natural Products Chemistry
• Cell Biology

Background:

• Breast and ovarian cancers are significant causes of cancer mortality in women.
• Natural compounds are increasingly explored for their antiproliferative effects against cancer.
• Olive Leaf Extract (OLE) is a natural product with potential therapeutic applications.

Purpose of the Study:

• To investigate the antitumor potential of Olive Leaf Extract (OLE) in triple-negative breast (MDA-MB-231) and ovarian (OVCAR-3) cancer cell lines.
• To elucidate the mechanisms underlying OLE's effects on cancer cell viability, proliferation, apoptosis, and mitochondrial function.

Main Methods:

• High-Performance Liquid Chromatography with Diode Array Detection (HPLC/DAD) for OLE composition analysis.
• Cell viability assays (MTS), cell cycle analysis, Western Blotting for apoptosis markers (cleaved-PARP, caspase 9).
• Mitochondrial function assays, reactive oxygen species (ROS) measurement, and antioxidant treatment (N-acetylcysteine).

Main Results:

• OLE, rich in oleuropein, demonstrated significant anti-proliferative and pro-apoptotic activity in MDA-MB-231 cells.
• OLE inhibited OVCAR-3 cell viability, induced cell cycle arrest, and promoted apoptosis.
• OLE treatment reduced mitochondrial membrane potential and functionality, increasing ROS levels and inducing oxidative stress, which was reversed by N-acetylcysteine.

Conclusions:

• Olive Leaf Extract (OLE) possesses significant antitumor properties against triple-negative breast and ovarian cancer cells.
• The primary mechanism of OLE's antitumor activity involves the induction of mitochondrial reactive oxygen species (ROS) generation, leading to cell cycle arrest and apoptosis.
• OLE represents a promising natural agent for further investigation in cancer therapy.