Distinct phenotypes of cancer cells on tissue matrix gel

Abstract

Background: Breast cancer cells invading the connective tissues outside the mammary lobule or duct immerse in a reservoir of extracellular matrix (ECM) that is structurally and biochemically distinct from that of their site of origin. The ECM is a spatial network of matrix proteins, which not only provide physical support but also serve as bioactive ligands to the cells. It becomes evident that the dimensional, mechanical, structural, and biochemical properties of ECM are all essential mediators of many cellular functions. To better understand breast cancer development and cancer cell biology in native tissue environment, various tissue-mimicking culture models such as hydrogel have been developed. Collagen I (Col I) and Matrigel are the most common hydrogels used in cancer research and have opened opportunities for addressing biological questions beyond the two-dimensional (2D) cell cultures. Yet, it remains unclear whether these broadly used hydrogels can recapitulate the environmental properties of tissue ECM, and whether breast cancer cells grown on CoI I or Matrigel display similar phenotypes as they would on their native ECM. Methods: We investigated mammary epithelial cell phenotypes and metabolic profiles on animal breast ECMderived tissue matrix gel (TMG), Col I, and Matrigel. Atomic force microscopy (AFM), fluorescence microscopy, acini formation assay, differentiation experiments, spatial migration/invasion assays, proliferation assay, and nuclear magnetic resonance (NMR) spectroscopy were used to examine biological phenotypes and metabolic changes. Student's t test was applied for statistical analyses. Results: Our data showed that under a similar physiological stiffness, the three types of hydrogels exhibited distinct microstructures. Breast cancer cells grown on TMG displayed quite different morphologies, surface receptor expression, differentiation status, migration and invasion, and metabolic profiles compared to those cultured on Col I and Matrigel. Depleting lactate produced by glycolytic metabolism of cancer cells abolished the cell proliferation promoted by the non-tissue-specific hydrogel. Conclusion: The full ECM protein-based hydrogel system may serve as a biologically relevant model system to study tissue-and disease-specific pathological questions. This work provides insights into tissue matrix regulation of cancer cell biomarker expression and identification of novel therapeutic targets for the treatment of human cancers based on tissue-specific disease modeling.

Coupled Source-Sink Habitats Produce Spatial and Temporal Variation of Cancer Cell Molecular Properties as an Alternative to Branched Clonal Evolution and Stem Cell Paradigms

“…In line with this, secondary tumors in different tissue types from the primary tumor will evolve cancer cells with quite distinctive phenotypes appropriate to the specific tissue type (Klein et al, 2002;Quinn et al, 2021). Such divergences have also been seen in 3-D cancer cell culture experiments (Ruud et al, 2020).…”

Human Breast Extracellular Matrix Microstructures and Protein Hydrogel 3D Cultures of Mammary Epithelial Cells

“…The staining was performed as we previously reported [ 29 ] with modifications. Briefly, for staining of type I collagen (Col I) in HB-TMG, pig breast tissue matrix gel (PB-TMG; homemade as previously reported [ 28 ]), human Col I (Advanced BioMatrix, #5007), or Matrigel (Corning, #356230), silicone wells attached to Silane-Prep slides (Sigma) were coated with 10 µL of the hydrogels at the concentrations that will have elastic moduli similar to those of native tissue ECM upon polymerization as reported [ 29 ] or defined in the current study.…”

“…To explore a resolution of this question, we have recently generated ECM hydrogels from mouse or pig breast tissues that preserved the majority of the tissues’ ECM proteins essential for mimicking the native breast tissue microenvironment [ 11 , 28 ]. In addition to supporting normal or cancerous mammary epithelial cell survival and growth within a 3D space [ 11 , 28 , 29 ], the breast tissue ECM hydrogels induced the expression of epithelial cell membrane receptors and other biomarkers distinct from that of the cells grown on collagen or Matrigel. Additionally, human breast cancer cells exhibited distinguishable morphologies, differentiation, migration, invasion, and metabolic profiles when cultured on the different matrices [ 29 , 30 ].…”

“…In addition to supporting normal or cancerous mammary epithelial cell survival and growth within a 3D space [ 11 , 28 , 29 ], the breast tissue ECM hydrogels induced the expression of epithelial cell membrane receptors and other biomarkers distinct from that of the cells grown on collagen or Matrigel. Additionally, human breast cancer cells exhibited distinguishable morphologies, differentiation, migration, invasion, and metabolic profiles when cultured on the different matrices [ 29 , 30 ]. These observations highlight the importance of using tissue-related culture materials for tissue-specific cell cultures.…”

Mechanical Considerations of Bioprinted Tissue

“…Similarly, different imbalances in the "matrisome" of the liver are thought to contribute to the variety of different liver diseases (Arteel and Naba, 2020). Breast cancer cells grown on matrices of similar stiffness yet providing different matrix-derived biochemical cues displayed different morphologies, differentiation states, and metabolic profiles (Ruud et al, 2020). Thus, a key challenging aspect of tissue fabrication and bioprinting is packaging enough matrix mechanics and biological signals in a form that is printable and amenable to manipulation.…”