Figure 1.
FBA-TPQ preferentially decreases cell viability and growth of A2780 and OVCAR-3 cells but not normal IOSE-144 cells.
A, Chemical structure and molecular formula of FBA-TPQ; B, Cell viability (MTS) assay of human ovarian carcinoma cells (A2780 and OVCAR-3) and nontumorigenic OSE cells (IOSE144) after a 48 h incubation with FBA-TPQ; C&D&E, Cell growth inhibition after 0, 24, 48 or 72 h exposure of A2780 (C), OVCAR-3 (D) and IOSE-144 (E) cells to FBA-TPQ(at concentrations of 0, 0.5, 0.75 and 1.0 µM). All values are representative of at least three independent experiments with similar results, and are presented as the percentage of cell growth inhibition, where vehicle-treated cells were regarded as 100% viable (0% growth inhibition).
Figure 2.
FBA-TPQ induces dose-dependent apoptosis and G2/M cell cycle arrest in OVCAR-3 cells.
A, Apoptosis of OVCAR-3 cells treated with serial concentrations of FBA-TPQ for 24 hr; B, Data summary and analysis of the apoptotic index (Q1 reflects necrosis, Q2 reflects late apoptosis, Q3 reflects healthy cell population not affected by apoptosis or necrosis while Q4 reflects early apoptosis). C, Cell cycle evaluation of OVCAR-3 cells treated with serial concentrations of FBA-TPQ for 12 hr; D, Data analysis of cells presented as the percent distribution of a specific phase (*, p<0.05 versus the control, **, p<0.01 versus the control, respectively). Data are representative of values from at least three independent experiments with similar results.
Figure 3.
FBA-TPQ induces cellular ROS and regulates the p53-MDM2, and PI3K-Akt mediated pathways.
A&B, FBA-TPQ induces dose-dependent ROS stress in OVCAR-3 cells (A, the dose-dependent increase in the ROS as indicated by CM-H2DCFDA; B, Data summarized as the percentage compared with the control). C, Western blot analysis of cellular protein expression levels of the related pathway, indicating FBA-TPQ may take effects through the ROS-accompanied, and PI3K-Akt-mediated/p53-MDM2-related cell proliferation, apoptosis and cell cycle progression associated pathway on OVCAR-3 ovarian cancer cell lines after 24 h exposure (at 250,750 and 1000 nM concentrations).
Figure 4.
FBA-TPQ causes dissipation of the mitochondrial membrane potential and exerts potent tumor growth inhibition.
A and B, Fluorescence intensity (JC-1 produces red fluorescence within the mitochondria as JC-1-aggregates while emits green fluorescence when leaks into the cytoplasm as JC-1-monomers; Fluorescence intensity shift between green and red is proportional to the ΔΨm change) values of JC-1 dye at specific excitation wavelengths and the corresponding ratio of Red/Green change (% of the control) after exposure to FBA-TPQ for 24 h (*, p<0.05 versus the control). C&D, Inhibition of tumor growth in mice bearing OVCAR-3 xenograft tumors (*, p<0.05 versus the control; **, p<0.01 versus the control), and the corresponding body weight changes during the treatments (p>0.05); E, Western-blot analysis of proteins (of the mice xenograft tumors after FBA-TPQ treatment of 0, 1 or 10 mg/kg dosage) involved in the FBA-TPQ-triggered, and PI3K-Akt mediated/p53-MDM2-related pathway.
Figure 5.
Cartoon of the possible mechanisms of action by which FBA-TPQ excerts its anticancer activities.