Fibroblast Compression and Tumor Cells Migration

Role of Compression in Metastasis
Our Human Pancreatic Fibroblasts play a key role in this study.

Pancreatic fibroblasts are continuously gaining ground as an important component of tumor microenvironment that dynamically interact with cancer cells to promote tumor progression. In addition, these tumor-infiltrated fibroblasts can acquire an activated phenotype and produce excessive amounts of extracellular matrix creating a highly dense stroma, a situation known as desmoplasia. Maria Kalli, Panagiotis Papageorgis, Vasiliki Gkretsi, Triantafyllos Stylianopoulos. (2018). Solid Stress Facilitates Fibroblasts Activation to Promote Pancreatic Cancer Cell Migration. Annals of Biomedical Engineering. https://doi.org/10.1007/s10439-018-1997-7.

FIGURE 1. A schematic of the in vitro transmembrane pressure device. (a) Fibroblasts were grown as a monolayer on the transmembrane of a 0.4 lm transwell insert and a piston of adjustable weight was applying a compressive stress. Control cells were covered with an agarose cushion only. (b) The experimental set-up of the co-culture system consisted of fibroblasts and pancreatic cancer cells (MIA PaCa-2 or CFPAC-1) in the upper and lower chamber of a transwell insert, respectively. A piston with adjustable weight, applying 4.0 mmHg of compressive stress on fibroblasts for 48 h is shown. A co-culture system consisting of fibroblasts and cancer cells without a compressive load was used as a control.

FIGURE 2. Neuromics'  Human Pancreatic Fibroblast in culture-Controls and Compressed.

FIGURE 1. A schematic of the in vitro transmembrane pressure device. (a) Fibroblasts were grown as a monolayer on the transmembrane of a 0.4 lm transwell insert and a piston of adjustable weight was applying a compressive stress. Control cells were covered with an agarose cushion only. (b) The experimental set-up of the co-culture system consisted of fibroblasts and pancreatic cancer cells (MIA PaCa-2 or CFPAC-1) in the upper and lower chamber of a transwell insert, respectively. A piston with adjustable weight, applying 4.0 mmHg of compressive stress on fibroblasts for 48 h is shown. A co-culture system consisting of fibroblasts and cancer cells without a compressive load was used as a control.

Solid stress developed within tumors is able by itself to activate normal fibroblasts, which in turn produce excessive amounts of ECM proteins leading to desmoplasia.

Cancer-Associated Fibroblasts and Cancer Cell Migration

Highway for Cancer Metastasis

Cancer Associated Fibroblasts provide the Matrices  (ECMs) serve as cancer’s assistants as it spreads throughout the body.

Cancer cells (red) migrate on a CAF-derived extracellular matrix (green). VANDERBILT UNIVERSITY; BEGUM ERDOGAN, DONNA WEBB

Unlike other ECMs, which normally form dense meshes, these arrange into parallel bundles forming the highway for tumor cell migration (The Scientist-December 15, 2015).

3-D Screens Predict Breast Cancer Metastasis

Cell-ECM Interactions

3-D culturing solutions and methods are increasingly being used to created more in vivo like assays.

Here researchers use our Human Collagen IV extracellular matrix protein (ECM) to develop a simple biomaterial platform with systematic control over the ECM protein density and composition to determine if integrin binding governs how metastatic cells differentiate between secondary tissue sites: L.E. Barney, E.C. Dandley, L.E. Jansen, N.G. Reich, A.M. Mercurio, and S.R. Peyton. A cell–ECM screening method to predict breast cancer metastasis. Integr Biol (Camb). 2015 Feb 10; 7(2): 198–212. doi: 10.1039/c4ib00218k.

This publication details the creation of an in vitro fingerprint that is predictive of in vivo metastasis.

Figure: Biomaterial platform for integrin-mediated phenotyping. (a) Breast cancer cell lines with their known in vivo metastatic tropisms.  (b) Three distinct ECM microenvironments regulate integrin binding. (c) Adhesion and motility phenotypes of the MDA-MB-231 cell line. Black: ECM 1; blue: ECM 2; green: ECM 3.

Figure: Correlations between adhesion and migration responses identify potent integrin antibodies in vitro. Pairwise comparisons between adhesion and migration measurements in the (a, b) MDA-MB-231 and (c, d) SkBr3 cell lines across normal, EGF-stimulated, and integrin antibody conditions. Arrows highlight conditions where integrin antibodies increased migration metrics. Spearman correlations are indicated on each plot with two-tailed p-values. Circle: ECM 1; square: ECM 2; triangle: ECM 3; black: normal; green: EGF; blue: anti-β1 integrin; red: anti-α2 integrin; orange: anti-α6 integrin. (e, f) SkBr3 migration mechanisms are displayed via 10 random cell paths under (e) normal and (f) anti-β1 conditions. Red paths identify cells detaching and adhering elsewhere on the surface. Inset: representative images of cell morphology. Scale bar is 25 μm. (g) Individual cells that invaded into an overlaid 3D collagen gel from the ECM 1 surface after 48 hours. Bar indicates mean distance invaded of all invading cells. Inset: schematic of cells invading upward from the ECM surface into an overlaid gel.

A richer understanding of cancer metastasis is important for the development of new, more potent chemotherapies. I am hopeful 3-D/ECM assays become more embraced as a way to more accuratly determine in vivo cell behaviors.