Thai perilla (Perilla frutescens) leaf extract inhibits human breast cancer invasion and migration

Abstract

© 2018 by Maejo University, San Sai, Chiang Mai, 50290 Thailand. Thai perilla (Perilla frutescens), also called Nga-mon, contains a substantial quantity of bioactive substances including phenolics and flavonoids. These phytochemicals have been linked to various bioactivities of P. frutescens such as in vitro and in vivo anti-inflammatory, anti-oxidative and anti-cancer capacities. In this study we evaluated anti-invasive and anti-migratory activities of Thai perilla leaf extract (PLE) on human breast cancer cells, MDA-MB-231. Our results demonstrate that rosmarinic acid is the main constituent of PLE. In vitro cytotoxicity analysis shows that PLE, at 24-hr exposure, is not toxic to MDA-MB-231 cells. A Boyden chamber-based transmembrane assay shows that PLE at a non-toxic dose (12.5-50 µg/mL) dramatically exhibits an inhibitory effect on cell invasion and migration. Gelatin zymography shows that PLE at a concentration of 100-400 µg/mL dose-dependently decreases matrix metalloproteinase-9 (MMP-9) secretion (p < 0.05-0.001) and activity (p < 0.001). Our data indicate that PLE can inhibit breast cancer cell invasion and migration through the reduction in activity and availability of MMP-9. Our observations also suggest that rosmarinic acid in PLE may account for the anti-invasion and anti-migration activities. In particular, rosmarinic acid as a food-derived chemotherapeutic agent can potentially be used in cancer chemotherapy.