Figure 4

CXCR2 inhibition attenuates dHL-60 cell-promoted invasion of PANC-1 tumor spheroids in the “contact” scenario but not in the “separated” scenario. (a) Representative brightfield images showing invasion of tumor spheroids (boundary circled in yellow) into the surrounding collagen matrix at t = 0 h and 24 h after dHL-60 cells or culture medium ± 1 μM AZD-5069 were loaded into the central channel (“separated”) or along with tumor spheroids into the tumor gel channel (“contact”) of the NTI-chip. Scale bar, 50 µm. (b) Normalized invasion area (i), defined by the ratio of increase in the projected area of the invaded spheroids over 24 h to the initial projected area at t = 0 h, and normalized circularity (ii), defined by the ratio of spheroid circularity at t = 24 h to that at t = 0 h, in specified conditions. Each data point represents a spheroid and n = 57–100 spheroids per condition. Bars show mean ± SD with the mean values written above the points. At least three independent experiments were performed. ns: ≥ 0.05, ****: p < 0.0001, Brown-Forsythe and Welch ANOVA with Dunnett’s T3 multiple comparisons test.