Figure 6

Lipid raft disruption inhibits migration, invasion and angiogenesis of breast carcinoma cell lines. (A) Lipid raft disruption inhibits the migration of breast carcinoma cells. Intact MDA-MB-231 and ZR 751 cell spheroids of approximately the same diameter were selected. Spheroids were then transferred in serum-free medium, left untreated or treated with different concentrations of MβCD, and incubated for 48 hrs to allow for migration. Finally, cell migration was observed using a laser scanning microscope. (B) Lipid raft disruption inhibits the invasion of breast carcinoma cells. MDA-MB-231 cells (1 × 10⁶) were left untreated or pretreated with different concentrations of MβCD, washed, and allowed to migrate through Matrigel-coated transwell inserts (8-μM pores) for 24 hrs. The cells that invaded through the Matrigel-coated inserts were stained, counted and photographed under a light microscope. (C) Quantification of relative migration. (D) The percentage of invasion was quantified as described earlier. Values represented are mean ± S.D from three different experiments (**p < 0.001). (E) Lipid raft disruption inhibits angiogenesis of breast carcinoma cells. Conditioned media from MDA-MB-231 and ZR 751 cells, which were left untreated or pretreated with MβCD, were collected at 24 hr. 8 × 10³ human microvascular endothelial cells (HMEC) were cultured in the collected conditioned medium in 48-well plates for 24 hrs. After the incubation period, the medium was removed, and the cells stained with Hema-3 stain and examined under a microscope. (F) Quantification of angiogenesis in endothelial cells that were left untreated or pretreated with MβCD. Values are mean ± S.D. from three different experiments (*p < 0.01, **p < 0.001). (G) Lipid raft disruption increases the secretion of soluble uPAR. MDA-MB-231 and ZR 751 cells were left untreated or pretreated with MβCD, and conditioned medium was collected at the 48 hr. suPAR levels were measured and quantified by ELISA as per the manufacturer's instructions.