Objective: This study aimed to evaluate the cytotoxic effects of Arctium minus (Hill) Bernh. ssp. minus methanol extract derived from aerial parts on cancer cell lines

Material and Method: For cytotoxicity assays, two different human breast cancer cell lines (MCF-7 and MDA-MB-231) and healthy human fibroblast cell line (MRC-5)as a control were used. Cell viability determination was performed using the CellTiter-Blue method. One-Way ANOVA and Tukey post test were used for statistical analysis.

Result and Discussion:Cell viability has been detected between ratios of 27.8-38.7% for MCF-7 cancer cell line, and a significant cytotoxic activity was observed via the analysis (1 mg/mL extract treatment p< 0.022). However, 47.8-59.7% cell viability was observed for MDA-MB-231 cancer cell line, and MRC-5 healthy fibroblast cell line did not demonstrate any cell viability (92.4-105.4% cell viability). Depending on these data, MCF-7 cancer cell line and MRC-5 fibroblast healthy cell line were treated with Arcitum minus extract, then cell viability was detected by flow cytometry technique. The ratio of the cell death was higher in MCF-7 cancer
cell line (98%) compared with the MRC-5 fibroblast healthy cell line (25%) after the Arctium minus extract treatment. In conclusion, Arctium minus ssp. minus extract has significantly decreased the cell viability in MCF7 cancer cell line when compared with the MCR-5 fibroblast normal cell line.