Figure 2.

Metastatic state of MDA-MB-231 cells dictates cellular adhesion strength revealed by fluidic-based SCFS. (a) Individual cell, and (b) cell in a cluster (cell adherent to at least two cells) detachment of MDA-MB-231 WT, shCx43, and Cx43D cells. Adhesion forces of single cells reflect cell–substrate adhesion, while those of a cell in a cluster reflect cell–cell adhesion. (c–g) Comparison of F–D curves characteristic parameters (F_adh, D_max, and F_adh/D_max ratio, referred to as spring coefficient (S_c)) between MDA-MB-231 cells with varying expression of Cx43 and different cell culture categories (single cells vs cells in a cluster). (c) Average adhesion force measured in MDA-MB-231 cells with varying Cx43 expression in single and cluster cell states. (d) Intercellular adhesion forces of MDA-MB-231 cells with varying Cx43 expression are represented by the relative force change between cells in cluster and single-cell states. (e) Average longest cantilever elongation before detachment (represented by D_max) in single and cluster cell states. (f) Spring coefficient (S_c) concept and an illustrative schematic (not to scale) showing the elastic deformation capability of the cell upon pulling it from the surface using a hollow FluidFM cantilever. The ratio of F_adh (maximum force) over D_max (longest elongation before detachment) when pulling the cell characterizes cell elasticity potential and can be interpreted from the F–D curves. Adapted with permission from ref (24) reference # 1488717-1. Copyright 2024 RSC. (g) Average cell elasticity represented by F_adh/D_max between MDA-MB-231 cells in different culture states. The concept of cell elasticity was adapted from ref (25). The values depicted are the mean ± SEM from three separate experiments, and at least 15 cells were evaluated per condition. *** denotes a p-value <0.001, ** denotes a p-value <0.01, and * denotes a p-value <0.05 compared to different conditions using ANOVA followed by the post hoc Tukey HSD test.