Figure 6.

Anticancer effects of Mito-FF in relation with oxidative stress. (A) Quantification of mitochondrial ROS levels of Huh7 cells according to the increasing concentration of sorafenib by flow cytometric analysis. Mitochondrial ROS was determined by quantification of the red fluorescence that emits when MitoSOX Red reagent (a mitochondrial superoxide indicator) is oxidized by superoxide in the mitochondria. (B) Quantification of mitochondrial ROS levels of Huh7 cells according to the increasing concentration of Mito-FF by flow cytometric analysis. (C) [Top] Determination of mitochondrial membrane potential (MMP) using JC-1 dye in Huh7 S/R cells following sorafenib treatment. In normal cells, JC-1 fluorescent dyes can accumulate in the matrix of mitochondria, producing red fluorescence. However, when the MMP declined, JC-1 cannot gather in the matrix so that JC-1 exist in the matrix as monomer, producing green fluorescence. [Bottom] The ratio of the red (OD1) and green (OD2) optical density. As the concentration of sorafenib increased, the ratio in the Huh7-S cells declined; the ratio in the Huh7-R cells was unchanged. (D) [Top] Determination of MMP using JC-1 dye in Huh7 S/R cells following Mito-FF treatment. [Bottom] The ratio of the red and green optical density. As the concentration of Mito-FF increased, the ratios declined in both Huh7-S/R cells. Values are presented as mean ± standard deviation of three independent experiments. *P < 0.05. Abbreviation: Huh7-S cell; sorafenib-sensitive Huh7 cell; Huh7-R cell; sorafenib-resistant Huh7 cell; Mito-FF; mitochondria-accumulating phenylalanine dipeptide with triphenyl phosphonium.