Article Figures & Data
Figures
- Figure 1.
Cytotoxicity of artesunate (ART) towards cancer cell lines. J16, J-Jhan, H69, DU145, SK-Mel-28, HCT116, and U251 cells were treated with artesunate (0-286 μM) for 72 h and subjected to the XTT-assay. Mean±SEM (standard error of the mean) of at least three independent experiments are shown. IC50 values were determined from the fitted-dose response curves. The leukaemia cell line J-Jhan was the most sensitive and the melanoma cell line SK-Mel-28 was the least sensitive towards artesunate.
- Figure 2.
Cell cycle distribution after artesunate (ART) treatment. J-Jhan, H69, HCT116, and U251 cells were treated with artesunate (0.26-260 μM), incubated at 37°C for 6 h to 96 h, and stained with propidium iodide. The fluorescence intensity, representing the amount of cellular DNA, was measured by flow cytometry. Cell cycle distributions of untreated cells after 24 h were used as control. All depicted cell lines showed G2/M arrest after incubation with 26 μM artesunate for 48 h (J-Jhan and H69) or with 78 μM artesunate for 24 h (HCT116 and U251). Further incubation led to increased apoptosis.
- Figure 3.
Ploidy determination of cancer cells. The cell cycle phase distribution of untreated U251, HCT116, DU145 and SK-Mel-28 cells (dark) as well as healthy lymphocytes (light gray) was analysed by propidium iodide staining and flow cytometry in parallel. The ploidy of the lymphocytes in G1 phase was set to 2n. The ploidy of the cancer cell lines was calculated from the G1 marker means. All analysed cancer cell lines were aneuploid and possessed additional chromosomes.
- Figure 4.
Mitotic phenotypes of untreated and artesunate-treated U251 and HCT116 cells as assessed by confocal microscopy. Microtubules (red), centrosomes (green), and DNA (blue) were stained. A: Normal mitosis in untreated U251 cells. B: U251 cells showing abnormal cell phenotypes (predominantly observed in artesunate-treated cells). For quantitative analysis, the categories `remote centrosomes', `two connected nuclei per cell' and `two separated nuclei per cell' were summarised as `defect in cytokinesis'. Additionally, the categories `more than two centrosomes, one nucleus per cell' and `more than two centrosomes, multiple nuclei per cell' were grouped as `multiple centrosomes'. C: Quantification of mitotic phenotypes shown in A and B. U251 cells were either untreated (gray) or treated with 78 μM artesunate (red) for 24 h (unshaded) or 48 h (shaded); 100-400 cells per sample were analysed by fluorescence microscopy. D: Normal mitosis in untreated HCT116 cells and an additional phenotype of two connected cells. E: HCT116 cells showing abnormal cell phenotypes (predominately observed in artesunate-treated cells) comprising few microtubules and one or multiple nuclei per cell. F: Quantification of mitotic phenotypes shown in D and E. HCT116 cells were either untreated (gray) or treated with 78 μM artesunate (red) for 24 h (unshaded) or 48 h (shaded); 100-400 cells per sample were analysed by fluorescence microscopy. The data represent the sum of two independent experiments.
- Figure 5.
Growth inhibition by artesunate in wild-type and knockout strains of S. cerevisiae. Wild-type, Δbub1, Δbub2, Δbub3, Δmad1, Δmad2, and Δmad3 yeast cells were treated with artesunate (0-600 μM) and incubated for 24 h. The OD600 was determined and normalised to 100% for untreated cells. The IC30 was calculated from the fitted dose-response curves. Mean±SEM (standard error of the mean) of at least two independent experiments are shown. The Δbub3 mutant was the most sensitive and the Δmad2 mutant was the least sensitive towards artesunate.
