Figure 1

DHA targets PDGFRα and selectively inhibits the growth and migration of PDGFRα-positive ovarian cancer cells. (a) The mRNA and protein expression of PDGFRα and PDGFRβ in human A2780, OVCAR3, SK-OV3 and OVCAR5 ovarian cancer cells, and the non-malignant ovarian epithelial cell line, IOSE144. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used as an internal control. (b) The results of the CCK-8 assay evaluating the viability of ovarian cancer cells and non-malignant cells after a 48-h exposure to DHA. (c) The results of the cell migration assay using A2780, OVCAR3 and SK-OV3 cells treated with DHA for 12 h. (d) The chemical structures of DHA and biotinylated DHA (DHA-biotin). (e) The viability of A2780 cells after incubation with various concentrations of DHA and biotinylated DHA (DHA-biotin) for 48 h. (f) The direct interaction of DHA with solubilized endogenous PDGFRα. A2780 cell lysates were incubated with free biotin or biotin-labeled DHA at various concentrations (0, 10, 50, 100 μM), which were then conjugated with neutroavidin-agarose beads in the presence or the absence of 50 μM of non-labeled DHA. The bound protein was detected using an anti-PDGFRα antibody. The data are representative of more than three experiments with similar results. (g) DHA-biotin directly binds the PDGFRα intercellular domain. The 293T cells transfected with full-length (FL) PDGFRα or c-KIT, or the chimera receptors, and the cell lysates were incubated with biotin-labeled DHA at indicated concentration followed by streptavidin pulldown and immunoblotting analysis. The data shown are the means±s.e.m. for three independent experiments. PDGFR, platelet-derived growth factor receptor; DHA, dihydroartemisinin.