Tumor cells can engage in a process called collective invasion, in which cohesive groups of cells invade through interstitial tissue. Here, we identified an epigenetically distinct subpopulation of breast tumor cells that have an enhanced capacity to collectively invade. Analysis of spheroid invasion in an organotypic culture system revealed that these “trailblazer” cells are capable of initiating collective invasion and promote non-trailblazer cell invasion, indicating a commensal relationship among subpopulations within heterogenous tumors. Canonical mesenchymal markers were not sufficient to distinguish trailblazer cells from non-trailblazer cells, suggesting that defining the molecular underpinnings of the trailblazer phenotype could reveal collective invasion-specific mechanisms. Functional analysis determined that
Jill M. Westcott, Amanda M. Prechtl, Erin A. Maine, Tuyen T. Dang, Matthew A. Esparza, Han Sun, Yunyun Zhou, Yang Xie, Gray W. Pearson
Breast cancer cell lines contain subpopulations of invasive trailblazer and noninvasive opportunist cells.