Cytotoxic Activities of Certain Medicinal Plants on Different Cancer Cell Lines

Abstract

Objectives: In recent years, the use of plants for the prevention and treatment of cancer is gaining more attention due to their diverse range of phytochemical constituents and fewer adverse effects. In this study, four medicinal plant species from the Kars province of Turkey were investigated for their cytotoxic potential against six different cancer cell lines and one normal cell line.

Materials and methods: MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-dipenyltetrazolium bromide] assay was performed to assess cytotoxic activity and apoptotic effect was determined using flow cytometry and caspase-3 analyses.

Results: Significant cytotoxicity (≥70%) was observed with the leaf extract of Artemisia absinthium on A-549, CCC-221, K-562, MCF-7, PC-3 cells, whereas seed extracts caused significant cytotoxicity (≥70%) on CCC-221, K-562, MCF-7, PC-3 cells. Selective cytotoxicity was obtained with leaf extract on A-549 and K-562 cells; and with seed extract on K-562, MCF-7 and PC-3 cells compared with normal Beas-2B cells. The levels of cytotoxicity for both extracts were time- and dose-dependent at lower concentrations. Moreover, selective cytotoxicity (78%) was detected on A-549 cells with the seed extract of Plantago major. Cytotoxicity of extracts from Hyoscyamus niger and Amaranthus retrosa ranged between 10% and 30%.

Conclusion: A. absinthium extracts and P. major seed extract have potential for development as therapeutic agents for cytotoxicity on certain cancer cells following further investigation.

Keywords: Artemisia absinthium; Cytotoxicity; apoptosis; cancer cells; medicinal plants.

Figure 1

Cytotoxicity of plant extracts on different cancer cell lines. Cells were treated with leaf or seed extracts of plants at 4 mg/mL concentration for 72 hr. Cytotoxicity was determined using MTT assays and results expressed as percentages of cytotoxicity compared with untreated control. Data expressed as mean ± standard deviation, n=3

Figure 2

Time-based dose response curves of cancer cells. A-549 cells (a, b) or K-562 cells (c, d) were treated with leaf or seed extracts of A. absinthium at various concentrations ata are expressed as mean ± standard deviation, n=3 ----■----: 0.1 mg/mL, —■—: 0.2 mg/mL, ----▲----: 0.5 mg/mL, —▲— : 1 mg/mL, ----------: 2 mg/mL, ———: 5 mg/mL

Figure 3

Flow cytometric analysis of apoptosis. A-549 cells were treated with leaf or seed extracts of A. absinthium at various concentrations. Results showing cells in necrosis (Q1), late apoptosis (Q2), live cells (Q3) and early apoptosis (Q4), for control (a), 0.25 mg/mL (b), 0.5 (c), 2 mg/mL (d), 4 mg/mL (e)

Figure 4

The effects of A. absinthium leaf extract on caspase-3 activity in A-549 cells as detected using a colorimetric assay. Treatment of cells with A. absinthium leaf extract exhibited 4.5-fold higher OD values than untreated cells. Data expressed as mean ± standard deviation, n