Fig. 1: ITGB1 phosphorylation supports efficient cancer cell invasion.
From: Dynamic regulation of integrin β1 phosphorylation supports invasion of breast cancer cells
a, A schematic highlighting the membrane-proximal and membrane-distal NPxY motifs of ITGB1. b, A schematic of the fibroblast-contracted 3D collagen matrix invasion assay platform. c, Left: representative images of MM231 triple-negative breast cancer cells expressing either ITGB1(WT or YYFF), invading into 3D fibroblast-contracted collagen I and stained with pan-cytokeratin (PanCK) to specifically detect the cancer cells and exclude fibroblasts from the analysis. Scale bars, 100 μm. Right: quantification of invasion beyond 100 μm, normalized to the total number of cells per region (n = 24 regions per cell line pooled from three biological replicates; unpaired two-tailed Student’s t-test with a Welch’s correction). d, Representative images (left) and quantification of cell shape (that is, solidity) (right) of MM231 cells (green is the actin staining) embedded in 3D collagen matrices overnight (magenta) (n = 104 (parental), 76 (shβ1), 84 (ITGB1(WT)) and 116 (ITGB1(YYFF)) cells pooled from three biological replicates; Kruskal–Wallis test with a Dunn’s correction for multiple comparisons). Scale bars, 20 μm. e, Representative H&E images (left) and quantification (right) of local invasion of MM231 ITGB1(WT or YYFF) cells into the mouse dermis from subcutaneous xenografts. Scale bars, 200 μm (n = 9 ITGB1(WT) or 11 ITGB1(YYFF) mice, respectively; unpaired two-tailed Student’s t-test with a Welch’s correction). The dotted line indicates the tumour boundary, where it meets the subcutaneous stromal cells. The boxplots represent the median and interquartile range (IQR). The whiskers extend to the minimum and maximum values. The grey areas on the boxplots highlight the IQR of the control conditions. NS, not significant. *P < 0.05, ***P < 0.001.
