p37 peptide suppresses cell growth and induces apoptosis in breast cell lines.

<p>(A) Flow cytometric analysis of cell surface gp96 levels in breast cancer cells. (B) Cells were treated with 50 μg/ml of p37 for 48 h. Cellular apoptosis were analyzed by FACS, and the percentage of apoptotic cells (Annexin V single positive and Annexin V/PI double positive) was determined. (C) CCK-8 assay of cell proliferation upon treatment with various concentrations of p37 peptide for 48 h. Results are presented as means ± SD from three independent experiments. (D) SK-BR-3 cells were transfected with gp96 or control siRNA for 48 h. Cells were treated with 20 μg/ml of p37 or control peptide for additional 48 h. Cellular apoptosis were analyzed by FACS. Results are presented as means ± SD from three independent experiments. (E) Representative <i>in vivo</i> luciferase images of SK-BR-3 xenograft nude mice at day 21 after p37 (8 mg/kg) treatment. (F) T47D and Bcap-37 xenograft tumor volume in response to p37 (8 mg/kg) treatment. Data shown are the means and SDs of five mice. Data are representative of two independent experiments. **, <i>P</i> < 0.01 compared with controls.