Abstract
BACKGROUND/OBJECTIVES: Perilla frutescens Britton leaves are a commonly consumed vegetable in different Asian countries including Korea. Cancer is a major cause of human death worldwide. The aim of the current study was to investigate the inhibitory effects of ethanol extract of perilla leaf (PLE) against important characteristics of cancer cells, including unrestricted growth, resisted apoptosis, and activated metastasis, using human cancer cells. MATERIALS/METHODS: Two human cancer cell lines were used in this study, HCT116 colorectal carcinoma cells and H1299 non-small cell lung carcinoma cells. Assays using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide were performed for measurement of cell growth. Soft agar and wound healing assays were performed to determine colony formation and cell migration, respectively. Nuclear staining and cell cycle analysis were performed for assessment of apoptosis. Fibronectin-coated plates were used to determine cell adhesion. RESULTS: Treatment of HCT116 and H1299 cells with PLE resulted in dose-dependent inhibition of growth by 52-92% (at the concentrations of 87.5, 175, and 350 µg/ml) and completely abolished the colony formation in soft agar (at the concentration of 350 µg/ml). Treatment with PLE at the 350 µg/ml concentration resulted in change of the nucleus morphology and significantly increased sub-G1 cell population in both cells, indicating its apoptosis-inducing activity. PLE at the concentration range of 87.5 to 350 µg/ml was also effective in inhibiting the migration of H1299 cells (by 52-58%) and adhesion of both HCT116 and H1299 cells (by 25-46%). CONCLUSIONS: These results indicate that PLE exerts anti-cancer activities against colon and lung cancers in vitro. Further studies are needed in order to determine whether similar effects are reproduced in vivo.