Figure 6.

The 1,25-(OH)₂D₃-induced cell cycle arrest and apoptosis of breast cancer cells and the motility and invasive potential of 1,25-(OH)₂D₃-treated breast cancer were abrogated by Ras overexpression.

Notes: Breast cancer cells were treated with 1,25-(OH)₂D₃ alone or together with the overexpression of Ras by using plasmid for 48 hours. (A) The apoptosis rates of treated MCF-7 cells and MDA-MB-453 cells were measured by flow cytometry assay. Statistical analysis of apoptosis rates of MCF-7 (B) and MDA-MB-453 (C) cells. (D) The cell cycle of treated MCF-7 cells and MDA-MB-453 cells were measured by flow cytometry assay. Statistical analysis of cell cycles of MCF-7 (E) and MDA-MB-453 (F) cells. (G) Cell migration was determined using wound healing migration assay (×40). The width of wound was measured using a microscope. (H) Statistical analysis of relative migration indexes of MCF-7 and MDA-MB-453 cells during wound healing migration assay. (I) MCF-7 and MDA-MB-453 cells were plated in upper compartments of Matrigel invasion chambers and exposed to 1,25-(OH)₂D₃ alone or together with the overexpression of Ras. Then, invasive potential of treated cells was evaluated microscopically. (J) Numbers of invading cells were determined by counting using a microscope. Data are mean ± SD of three independent experiments. *P<0.05, **P<0.01 vs Control, ^#P<0.05 vs 0.1 µm.

Abbreviations: 1,25-(OH)₂D₃, 1,25-dihydroxy vitamin D₃; PI, propidium iodide.