skip to main content


Title: Tunable 3D Hydrogel Microchannel Networks to Study Confined Mammalian Cell Migration
Abstract

Cells adapt and move due to chemical, physical, and mechanical cues from their microenvironment. It is therefore important to create materials that mimic human tissue physiology by surface chemistry, architecture, and dimensionality to control cells in biomedical settings. The impact of the environmental architecture is particularly relevant in the context of cancer cell metastasis, where cells migrate through small constrictions in their microenvironment to invade surrounding tissues. Here, a synthetic hydrogel scaffold with an interconnected, random, 3D microchannel network is presented that is functionalized with collagen to promote cell adhesion. It is shown that cancer cells can invade such scaffolds within days, and both the microarchitecture and stiffness of the hydrogel modulate cell invasion and nuclear dynamics of the cells. Specifically, it is found that cell migration through the microchannels is a function of hydrogel stiffness. In addition to this, it is shown that the hydrogel stiffness and confinement, influence the occurrence of nuclear envelope ruptures of cells. The tunable hydrogel microarchitecture and stiffness thus provide a novel tool to investigate cancer cell invasion as a function of the 3D microenvironment. Furthermore, the material provides a promising strategy to control cell positioning, migration, and cellular function in biological applications, such as tissue engineering.

 
more » « less
PAR ID:
10447311
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Healthcare Materials
Volume:
10
Issue:
23
ISSN:
2192-2640
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Abstract The collagen-rich tumor microenvironment plays a critical role in directing the migration behavior of cancer cells. 3D collagen architectures with small pores have been shown to confine cells and induce aggressive collective migration, irrespective of matrix stiffness and density. However, it remains unclear how cells sense collagen architecture and transduce this information to initiate collective migration. Here, we tune collagen architecture and analyze its effect on four core cell-ECM interactions: cytoskeletal polymerization, adhesion, contractility, and matrix degradation. From this comprehensive analysis, we deduce that matrix architecture initially modulates cancer cell adhesion strength, and that this results from architecture-induced changes to matrix degradability. That is, architectures with smaller pores are less degradable, and degradability is required for cancer cell adhesion to 3D fibrilar collagen. The biochemical consequences of this 3D low-attachment state are similar to those induced by suspension culture, including metabolic and oxidative stress. One distinction from suspension culture is the induction of collagen catabolism that occurs in 3D low-attachment conditions. Cells also upregulate Snail1 and Notch signaling in response to 3D low-attachment, which suggests a mechanism for the emergence of collective behaviors. 
    more » « less
  2. Abstract

    Cancer progression involves complex signals within the tumor microenvironment that orchestrate proliferation and invasive processes. The mechanical properties of the extracellular matrix (ECM) within this microenvironment has been demonstrated to influence growth and the migratory phenotype that precedes invasion. Here we present the integration of a label-free quantitative phase imaging technique, spatial light interference microscopy (SLIM)—with protein-conjugated hydrogel substrates—to explore how the stiffness of the ECM influences melanoma cells of varying metastatic potential. Melanoma cells of high metastatic potential demonstrate increased growth and velocity characteristics relative to cells of low metastatic potential. Cell velocity in the highly metastatic population shows a relative stability at higher matrix stiffness suggesting adoption of migratory routines that are independent of mechanics to facilitate invasion. The use of SLIM and engineered substrates provides a new approach to characterize the invasive properties of live cells as a function of microenvironment parameters. This work provides fundamental insight into the relationship between growth, migration and metastatic potential, and provides a new tool for profiling cancer cells for clinical grading and development of patient-specific therapeutic regimens.

     
    more » « less
  3. Abstract

    Bioprinting is an emerging approach for fabricating cell‐laden 3D scaffolds via robotic deposition of cells and biomaterials into custom shapes and patterns to replicate complex tissue architectures. Bioprinting uses hydrogel solutions called bioinks as both cell carriers and structural components, requiring bioinks to be highly printable while providing a robust and cell‐friendly microenvironment. Unfortunately, conventional hydrogel bioinks have not been able to meet these requirements and are mechanically weak due to their heterogeneously crosslinked networks and lack of energy dissipation mechanisms. Advanced bioink designs using various methods of dissipating mechanical energy are aimed at developing next‐generation cellularized 3D scaffolds to mimic anatomical size, tissue architecture, and tissue‐specific functions. These next‐generation bioinks need to have high print fidelity and should provide a biocompatible microenvironment along with improved mechanical properties. To design these advanced bioink formulations, it is important to understand the structure–property–function relationships of hydrogel networks. By specifically leveraging biophysical and biochemical characteristics of hydrogel networks, high performance bioinks can be designed to control and direct cell functions. In this review article, current and emerging approaches in hydrogel design and bioink reinforcement techniques are critically evaluated. This bottom‐up perspective provides a materials‐centric approach to bioink design for 3D bioprinting.

     
    more » « less
  4. This study aimed to understand extracellular mechanical stimuli’s effect on prostate cancer cells’ metastatic progression within a three-dimensional (3D) bone-like microenvironment. In this study, a mechanical loading platform, EQUicycler, has been employed to create physiologically relevant static and cyclic mechanical stimuli to a prostate cancer cell (PC-3)-embedded 3D tissue matrix. Three mechanical stimuli conditions were applied: control (no loading), cyclic (1% strain at 1 Hz), and static mechanical stimuli (1% strain). The changes in prostate cancer cells’ cytoskeletal reorganization, polarity (elongation index), proliferation, expression level of N-Cadherin (metastasis-associated gene), and migratory potential within the 3D collagen structures were assessed upon mechanical stimuli. The results have shown that static mechanical stimuli increased the metastasis progression factors, including cell elongation (p < 0.001), cellular F-actin accumulation (p < 0.001), actin polymerization (p < 0.001), N-Cadherin gene expression, and invasion capacity of PC-3 cells within a bone-like microenvironment compared to its cyclic and control loading counterparts. This study established a novel system for studying metastatic cancer cells within bone and enables the creation of biomimetic in vitro models for cancer research and mechanobiology.

     
    more » « less
  5. Abstract

    Glioblastoma (GBM), characterized by high infiltrative capacity, is the most common and deadly type of primary brain tumor in adults. GBM cells, including therapy‐resistant glioblastoma stem‐like cells (GSCs), invade the healthy brain parenchyma to form secondary tumors even after patients undergo surgical resection and chemoradiotherapy. New techniques are therefore urgently needed to eradicate these residual tumor cells. A thiol‐Michael addition injectable hydrogel for compatibility with GBM therapy is previously characterized and optimized. This study aims to develop the hydrogel further to capture GBM/GSCs through CXCL12‐mediated chemotaxis. The release kinetics of hydrogel payloads are investigated, migration and invasion assays in response to chemoattractants are performed, and the GBM‐hydrogel interactions in vitro are studied. With a novel dual‐layer hydrogel platform, it is demonstrated that CXCL12 released from the synthetic hydrogel can induce the migration of U251 GBM cells and GSCs from the extracellular matrix microenvironment and promote invasion into the synthetic hydrogel via amoeboid migration. The survival of GBM cells entrapped deep into the synthetic hydrogel is limited, while live cells near the surface reinforce the hydrogel through fibronectin deposition. This synthetic hydrogel, therefore, demonstrates a promising method to attract and capture migratory GBM cells and GSCs responsive to CXCL12 chemotaxis.

     
    more » « less