Dynamic Switch Between Two Adhesion Phenotypes in Colorectal Cancer Cells

Abstract

The hematogenous metastatic cascade is mediated by the interaction of cancer cells and the endothelial cell lining of blood vessels. In this work, we examine the colon cancer cell line COLO 205, which grows simultaneously in both adherent and suspended states in culture and can serve as a good model for studying tumor heterogeneity. The two subpopulations of cells have different molecular characteristics despite being from the same parent cell line. We found that the ratio of adherent to suspended cells in culture is maintained at 7:3 (equilibrium ratio). The ratio was maintained even when we separate the two populations and culture them separately. After 8 h in culture the equilibrium was achieved only from either adherent or suspended population. The adherent cells were found to express less E-selectin binding glycans and demonstrated significantly weaker interaction with E-selectin under flow than the suspended cells. Manipulation of the epithelial–mesenchymal transition (EMT) markers β-catenin and E-cadherin expression, either by siRNA knockdown of β-catenin or incubation with E-cadherin antibody-coated microbeads, shifted the ratio of adherent to suspended cells to 9:1. Interestingly, human plasma supplemented media shifted the ratio of adherent to suspended cells in the opposite direction to 1:9, favoring the suspended state. The dynamic COLO 205 population switch presents unique differential phenotypes of their subpopulations and could serve as a good model for studying cell heterogeneity and the EMT process in vitro.

CellTrans: An R Package to Quantify Stochastic Cell State Transitions

“…This equilibrium solution well corresponds to the experimental findings. The predictions of CellTrans and the ad hoc ODE in the work by Geng et al 7 are in good accordance with the original data (RMSD CellTrans vs ODE: 0.0219 vs 0.0278 for the experiment starting with pure adherent cultures and RMSD CellTrans vs ODE: 0.02709 vs. 0.02407 for the experiment starting with pure suspended cultures) (see also Figure 2B).…”

“…Typically, the dynamics between different cell states is described by formulating ODEs incorporating parameters which describe detailed cell properties such as symmetrical/asymmetrical division rates and transition rates between cell states. 5,7 Another possibility to model the evolution of cell state proportions is discrete-time Markov models. Discrete-time Markov models are particular stochastic processes which can be understood as sequences of random variables indexed by discrete time points, where the next state only depends on the current state of the process but is independent of earlier states.…”

“…Summary. It remains unclear in which way the "best-fit" solution in the introduced ODE approach in the work by Geng et al 7 has been obtained. Instead of fitting parameters, our approach offers a transparent estimation of the underlying transition matrix yielding good predictions.…”

Intestinal Epithelial HuR Modulates Distinct Pathways of Proliferation and Apoptosis and Attenuates Small Intestinal and Colonic Tumor Development

“…The observation that tumor burden in perinatal Apc min/+ HuR IKO mice was indistinguishable from control mice suggest that perinatal small intestinal epithelial HuR is not essential for adenoma initiation. Further studies focusing on mesenchymal/stromal HuR deletion will be required to examine the contribution of non-epithelial intestinal HuR in tumorigenesis and the cross talk between stromal and epithelial compartments in tumor initiation and progression (40–42). …”

Tumacrophage: macrophages transformed into tumor stem-like cells by virulent genetic material from tumor cells

“…To test this speculation, we isolated monocyte/macrophages from cancer patients and interrogated them for the presence of tumor marker gene expression by PCR. Colorectal and breast cancer patients were selected for this analysis in light of their hematogenous metastatic propensity [ 57 , 58 ]. To enrich for monocyte/macrophage and reduce the presence of CTCs (circulating tumor cells), we employed immunomagnetic beads [ 2 , 3 ].…”