Howard : A Proteomics Based Approach for Material Selection in a Model of the Pre-Metastatic Niche
A Proteomics Based Approach for Material Selection in a Model of the Pre-Metastatic Niche
Madison Howard1, Evelyn Nonamaker1, Luis Solorio1,2
1 Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907
2 Purdue Center for Cancer Research, Purdue University, West Lafayette, IN 47907
Fibronectin (FN) is an essential extracellular matrix protein commonly used in tissue engineered models due to its attractive cell attachment properties. FN has been found to increase during pre-metastatic niche formation, making it of particular interest for use in in vitro models. Our lab has developed various breast cancer pre-metastatic niche models but found varying levels of fibrillar formation across different commercial brands of FN, thereby potentially altering the efficacy of the model.
Here, we compared five commercially available human-derived FN products used for cell culture. We evaluated fibrillar FN formation and coating efficiency on 3D SU-8 scaffolds using confocal microscopy. Proteomic analysis was performed on each product to determine the overall protein composition and peptide expression levels for the FN1 gene.
We found only two of the commercial brands analyzed (Corning and Sigma Aldrich) formed FN fibrils on the scaffolds and our proteomic analysis revealed all the brands had unique compositional signatures. EMD showed high levels of blood clotting proteins, while Advanced Biomatrix had upregulated levels of immune response proteins. Examination of amino acid sequence domains demonstrated domains associated with fibrillogenesis were significantly upregulated in Sigma and Corning.
These data indicate the choice of commercial FN products could affect how well in vitro models mimic the pre-metastatic niche. Future work will compare FN secreted by human lung fibroblasts and Ca1h breast cancer cells to the commercial products to determine which product most accurately represents the pre-metastatic niche.
Translational/Human Health Impact:
Metastasis is the single greatest driver of breast cancer related mortalities, where the five-year survival rate drops almost 75% when the disease progresses into a metastatic state. There is a critical need to model the breast cancer pre-metastatic niche to probe how cancer cells remodel their environment and how the extracellular matrix (ECM) affects cancer cell growth and drug sensitivity. To develop this model, we must first determine which materials, including FN, are most representative of the pre-metastatic niche. Our work will aid researchers in their material selection process and help ensure the models being produced are as physiologically relevant as possible and can be used to help create better treatments for patients.