Fig. 4. YLT-11 induced mitotic defects and disturbed mitotic checkpoint function.

a MDA-MB-468 and MDA-MB-231 cells were treated with DMSO or 0.5 μM YLT-11 for 30 h and then stained with DAPI to detect the karyomorphism in different stages. Multinucleation, micronuclei, and chromosome mal-disjunction were marked by arrowheads. b Percentage of cells with mitotic catastrophe is quantified. Columns, means (n = 3); bars, standard deviation, (***p < 0.001). c Breast cancer cell lines were treated with an increasing concentration of YLT-11 for 30 h and stained with propidium iodide prior to analysis of DNA content by flow cytometry. Gating (>4N) indicated the percentage of aneuploid/polyploid cells. d Breast cancer cell lines were treated with YLT-11 (0.25 μM) for indicated times. Percentage of cancer cells in different stages. 2N, 4N, and >4N presented G1, G2/M, and aneuploid/polyploid cells, respectively. e Western analyses of key mitotic checkpoint protein. MDA-MB-468 cells were synchronized by nocodazole for 16 h and allowed to proceed in the presence or absence of 0.5 μM YLT-11. β-actin served as a loading control