Differential contractility regulates cancer stem cell migration

Phosphoproteomic Changes Induced by Cell-Derived Matrix and Their Effect on Tumor Cell Migration and Cytoskeleton Remodeling

“…Moreover, the migration trajectories of individual cells indicated that some tumor cells on CDMs migrated similarly to tumor cells on glass, while others assumed migration characteristics unique to CDMs (Figure B,C). Changes in the proportion of cancer stem-like (CSC) phenotype may underlie this heterogeneity as fibrotic ECM can promote stem-like properties in tumor cells. , Interestingly, CSCs exhibit enhanced directional migration while exerting weaker contractile forces, , and the migratory mesenchymal-CSCs preferentially localize to the invasive edge of tumors . To determine whether CDMs are enriching the CSC phenotype in MDA-MB-231 cells, a previously validated reporter cell line in which GFP expression is controlled by the stem cell transcription factor NANOG was used .…”

Towards a More Objective and High-throughput Spheroid Invasion Assay Quantification Method

“…Using pixels is less subjective than segmenting cells because it can be difficult to automatically distinguish individual cells when they are clustered (Supplementary Fig. 7), and manual tracing of cell boundaries is user-dependent and time consuming and cannot be completed if the cell boundaries are not evident [8,30,[37][38][39][40][41][42][43]62]. Automated spheroid invasion quantification methods such as TASI segment the spheroid mass as one object and, as a result, are limited to assessing the distance of invasion from the spheroid centroid or core boundary to the edge of a dense invasion front [47,48].…”

“…Cell invasion and migration are driving factors for various biological events such as development [1,2], wound healing [3][4][5][6], tumor metastasis [7][8][9] and host cell infiltration of implanted scaffolds [10][11][12][13]. The effects of soluble and immobilized chemical gradients on cell migration on 2D surfaces and infiltration into 3D matrices and tissues is well established [9,14]; however, it is also becoming clear that mechanical cues play a large role in cell invasion and migration [7,15].…”

“…However, phase images of spheroid invasion are difficult to analyze with common automated software. Thus, this method often requires manual tracing of cell boundaries in programs such as ImageJ/FIJI to quantify the extent of invasion via measuring the distances and areas of migrating cells [8,30,[37][38][39][40][41][42][43]. This manual tracing is time consuming and introduces subjectivity and possible technical error.…”

“…Quantification metrics for cell invasion into 3D matrices commonly involve the overall invasion area and/or the distance travelled by cells at a given timepoint [30,34,37,38,41,43,44,[47][48][49]. The invasion area is used to represent the number of invaded cells [30,34,37,38,41,43,44,[49][50][51], and the distance travelled is often reported as either the mean or maximum distance travelled by cells [8,30,41,49,52]. Yet, these metrics are sensitive to changes in cell size and shape that occur as cells migrate through the matrix [53,54].…”