FIGURE 7.

CXCR3 ligand chemokines promote invasion ability of MDA-MB-231 cells through induction of MMP-9 expression. A and B, a cell suspension containing MDA-MB-231 cells in serum-free medium containing CXCL9 (100 ng/ml), CXCL10 (20 ng/ml), or CXCL11 (50 ng/ml) in the absence or presence of anti-CXCR3 antibody (5 μg/ml) was seeded onto a basement membrane-coated filter and allowed to invade for 24 h. Invasive cells on the bottom of the insert were stained (A) and extracted for measurement of the OD at 560 nm in a plate reader (B). Cont, control. C, MDA-MB-231 cells were stimulated with CXCL9 (100 ng/ml), CXCL10 (20 ng/ml), or CXCL11 (50 ng/ml) for 24 h. Total RNA was isolated and assessed for MMP-2 or MMP-9 mRNA expression by real time-PCR. Values were normalized for GAPDH mRNA levels. The data shown represent the mean ± S.D. of three independent experiments performed in triplicate. ns, not significant; **, p < 0.01 compared with unstimulated control.