The lung extracellular matrix (ECM) maintains the structural integrity of the tissue and regulates the phenotype and functions of resident fibroblasts. Lung‐metastatic breast cancer alters these cell‐ECM interactions, promoting fibroblast activation. There is a need for bio‐instructive ECM models that match the ECM composition and biomechanics of the lung to study these cell‐matrix interactions in vitro. Here, a synthetic, bioactive hydrogel is synthesized that mimics the native lung modulus and includes a representative distribution of the most abundant ECM peptide motifs responsible for integrin‐binding and matrix metalloproteinase (MMP)‐mediated degradation in the lung, which enables quiescent culture of human lung fibroblasts (HLFs). Stimulation with transforming growth factor β1 (TGF‐β1), metastatic breast cancer conditioned media (CM), or tenascin‐C‐derived integrin‐binding peptide activated hydrogel‐encapsulated HLFs demonstrates multiple environmental methods to activate HLFs in a lung ECM‐mimicking hydrogel. This lung hydrogel platform is a tunable, synthetic approach to studying the independent and combinatorial effects of ECM in regulating fibroblast quiescence and activation.
Accurately replicating and analyzing cellular responses to mechanical cues is vital for exploring metastatic disease progression. However, many of the existing in vitro platforms for applying mechanical stimulation seed cells on synthetic substrates. To better recapitulate physiological conditions, a novel actuating platform is developed with the ability to apply tensile strain on cells at various amplitudes and frequencies in a high‐throughput multi‐well culture plate using a physiologically relevant substrate. Suspending fibrillar fibronectin across the body of the magnetic actuator provides a matrix representative of early metastasis for 3D cell culture that is not reliant on a synthetic substrate. This platform enables the culturing and analysis of various cell types in an environment that mimics the dynamic stretching of lung tissue during normal respiration. Metabolic activity, YAP activation, and morphology of breast cancer cells are analyzed within one week of cyclic stretching or static culture. Further, matrix degradation is significantly reduced in breast cancer cell lines with metastatic potential after actuation. These new findings demonstrate a clear suppressive cellular response due to cyclic stretching that has implications for a mechanical role in the dormancy and reactivation of disseminated breast cancer cells to macrometastases.
more » « less- NSF-PAR ID:
- 10449757
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 31
- Issue:
- 1
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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