Fig. 2From: Mitochondrially targeted vitamin E succinate efficiently kills breast tumour-initiating cells in a complex II-dependent mannerBreast TICs are resistant to chemotherapeutic drugs but sensitive to MitoVES. Adherent and sphere NeuTL (A) and MCF7 cells (B) were exposed to different concentrations of the agents for 24 h and viability assessed by the MTT assay. (C) NeuTL adherent and sphere cells were exposed to 50 μM α-TOS or 2 μM MitoVES for 24 h and inspected by light microscopy. Adherent or sphere NeuTL (D) or MCF7 cells (E) were exposed to α-TOS (50 μM), MitoVES (2 μM) or parthenolide (PTL; 10 μM) for 12 h and apoptosis evaluated using the annexin V/PI method. (F) Adherent NeuTL cells were exposed to 2 μM MitoVES for 24 h and evaluated for cell cycle distribution. (G) NeuTL sphere and adherent cells were exposed to 5 μM MitoVES for 12 h and full length and cleaved PARP, caspase-9 (C9), caspase-3 (C3) and caspase-8 assessed using WB with actin as loading control. The level of full length and cleaved proteins was evaluated by densitometry and related to actin. Data are mean values ± S.D. (n = 3). The symbol ‘*’ in panels A, B, D-F indicates statistically significant differences for adherent and sphere cells with p < 0.05. The symbol ‘*’ in panel G indicates statistically significant differences in the expression of the full length and cleaved protein with p < 0.05. Images in panel C are representative of three independent experimentsBack to article page