Figure 6.

Subpopulations exhibit differential morphologies, cell-ECM signaling, and contractility. a) Representative two-dimensional morphologies with red arrows pointing to parental cells with weakly motile-like morphologies and the green arrows pointing to parental cells with strongly motile-like morphologies; Scale bar: 50 μm. b) Quantification of cell area for subpopulations with and without E-cadherin. c) Western blot of pFAK, FAK, and GAPDH for MDA^PAR, MDA⁺, and MDA⁻. d) Western blot of pFAK, FAK, and GAPDH for MDA⁻ control and MDA⁻EcadKD. e) Western blot of pFAK, FAK, and GAPDH for MDA⁺, MDA⁺Ecad^Low, and MDA⁺Ecad^High. f) Quantification of FAK expression and activation from Western blot in (c) (n = 3). g) Quantification of FAK expression and activation from Western blot in (d) (n = 3). h) Quantification of FAK expression and activation from Western blot in (e) (n = 3). i) Quantification of focal adhesion area for subpopulations with and without E-cadherin. j) Total traction force magnitude, |F|, of MDA-MB-231 subpopulations with and without E-cadherin (n = 51–129). k) Percentage of bulk collagen matrix contraction for collagen gels seeded with MDA-MB-231 subpopulations with and without E-cadherin after 4 days (n = 4–14). Data from (f), (g), (h) and (k) display mean ± SEM. The box and whisker plots in (b), (i), and (j) shows medians, 25^th/75^th and minimum and maximum values. Statistical significance for (b), (i), and (j) were calculated using a Kruskal-Wallis H test. Statistical significance for (f), (h), and (k) were calculated using an ordinary, one-way ANOVA. Statistical significance for (g) was calculated using an unpaired, two-tailed Student’s t-test. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001, n.s. non-significant.