Cathepsin G, a Neutrophil Protease, Induces Compact Cell-Cell Adhesion in MCF-7 Human Breast Cancer Cells
Figure 4
Rap1 activation is involved in induction of cell condensation by cathepsin G. (a) MCF-7 cells were cultured in dishes coated with fibronectin. After 24 hours, the adherent cells were incubated in serum-free medium with 0.5 mU/mL cathepsin G for the indicated periods. Active Rap1 was analyzed by the pull-down assay. Western blotting of whole cell lysates was used to assess total levels of Rap1 (Total Rap1). The densitometric units represent Rap1 activity relative to cathepsin G-untreated cells (0 hour) taken as 1.0. (b) The adherent MCF-7 cells were treated with cathepsin G in the absence or presence of a Rap1 inhibitor GGTI-298 (5 M) for 5 hours. Cells were then analyzed by phase-contrast microscopy （original magnification: 200）.
