Figure 1.
High PS Expression Predicts Sensitivity to PC-SA in Cancer Cell Lines
(A and B) Size distribution (A) and zeta potential (B) of PC-SA liposomes (7:2 molar ratio). (C) Viability of 19 cancerous and non-cancerous cells and cell lines after incubation with increasing concentrations of PC-SA for 2 hr. All data points represent the mean of at least three experiments, with error bars indicating the SEM. (D) PS exposure (percent of annexin V binding) of different cancer and non-cancer cells (flow cytometric analysis, 3 independent experiments for each cell line). (E) PS expression as assessed by flow cytometry and plotted against the corresponding PC-SA EC50 for each cell line (n = 19 lines). A significant correlation was observed between PS expression and PC-SA EC50 values (Spearman’s rank correlation, p < 0.0001 by two-tailed t test). (F) Hemolytic assay in the presence of different concentrations of PC-SA (20–140 μg/mL). All concentrations show 0% hemolysis. (G) Interaction of Rhodamine B-PC-SA liposomes with B16F10 cancer cells in the presence or absence of annexin V or anti-PS antibodies, visualized under a confocal microscope (Leica TCS SP8, software LAS-X). Scale bars, 10 μm.