Antitumor Activity of Ethanolic Extract from <i>Thymbra Spicata L.</i> aerial Parts: Effects on Cell Viability and Proliferation, Apoptosis Induction, STAT3, and NF-kB Signaling

Abstract

Thyme-like plants including <i>Thymbra spicata L</i>. are widely used as food and folk medicinal remedies in the Mediterranean area. This study aimed to explore the in vitro antitumor potential of polyphenol-enriched extracts from aerial parts of <i>T. spicata</i>. The ethanolic extract significantly inhibited proliferation of different human tumor cell lines, without significant effects on non-neoplastic cells. A deeper investigation of the molecular mechanism sustaining the in vitro antitumor activity of the extract was carried on the human breast cancer cells MCF-7 in comparison with the normal breast cells MCF-10A. The effects on MCF-7 cells were associated with the following: <i>(i)</i> production of reactive oxygen species (ROS) and release of nitric oxide; <i>(ii)</i> apoptosis induction; and <i>(iii)</i> reduction in STAT3 and NF-kB phosphorylation. The ethanolic extract from <i>T. spicata</i> leaves might represent a novel therapeutic tool in combination with conventional chemotherapy to reduce the adverse side effects and drug resistance.