FIGURE 7.

Effect of VRK2 down-regulation on invasion of breast cancer MDA-MB-231 cells. A, MDA-MB-231 cells were transfected in p60 dishes with control siRNA (siControl) or VRK2-specific siRNA (siVRK2-06). After 3 days, cells were treated as control or stimulated with PMA/Io for 30 min; afterward, 50,000 cells were placed in serum-free medium in the upper chamber of a Transwell coated with Matrigel (1 mg/ml). Medium with 10% FBS was added in the lower chamber. The invasion assay was performed for 42 h. Invasive cells were fixed with 4% paraformaldehyde and stained with 0.5% crystal violet dye. The microscopic image of the invasive cells is shown to the left. The mean values from duplicate samples of three independent experiments are shown to the right. ***, p < 0.0005. At the bottom is shown the level of COX-2 protein (left) and the level of VRK2 mRNA by quantitative RT-PCR (right). B, protein levels of VRK2 and NFAT1 in human cell lines of different origins. Jurkat (T-cells), SW-620 (colon carcinoma), MDA-MB-435 (melanoma), and MDA-MB-231 (breast cancer). The antibodies used are indicated under “Experimental Procedures.” Error bars, S.D.