Subject(s)
Coated Materials, Biocompatible/chemistry , Nanostructures/chemistry , Osteoblasts/metabolism , Phosphorus/chemistry , Titanium/chemistry , Animals , Cell Adhesion , Coated Materials, Biocompatible/metabolism , Electrochemical Techniques , Electrodes , Hydrophobic and Hydrophilic Interactions , Mice , Osteoblasts/cytology , Oxides/chemistry , Porosity , Surface Properties , Titanium/metabolismABSTRACT
It is well recognized that one of the major drawbacks of using traditional two dimensional cultures to model the living systems is inaccurately reflecting the physiological manner in which modulators, nutrients, oxygen, and metabolites are applied and removed. Moreover, the two dimensional culture system poorly reflects how different cell types interact with each other in the same microenvironment. Since the first global development of three dimensional (3D) cell culture techniques in the late 1960s, this last decade has seen an explosion of studies to promote 3D models in the fields of regenerative medicine and cancer. The recent surge of interest in 3D cell culture in cancer research is attributable to the interest in developing closer to real life models. The ability to include various cell types and extracellular components reflect more the physiological conditions of tumor microenvironment. In this short review, we will discuss different approaches of 3D culture system models and techniques with a focus on the 3D interactions of cancer cells with stromal cells in the goal to reevaluate old and develop new therapeutics.
Subject(s)
Cell Culture Techniques , Neoplasms/pathology , Drug Evaluation, Preclinical/methods , Humans , Lab-On-A-Chip Devices , Neoplasms, Connective Tissue/pathology , Neoplasms, Glandular and Epithelial/pathology , Research Design , Spheroids, Cellular , Tissue Scaffolds , Tumor Cells, Cultured , Tumor MicroenvironmentABSTRACT
To improve treatment of obesity, a contributing factor to multiple systemic and metabolic diseases, a better understanding of metabolic state and environmental stress at the cellular level is essential. This work presents development of a three-dimensional (3D) in vitro model of adipose tissue displaying induced lipid accumulation as a function of fatty acid supplementation that, subsequently, investigates cellular responses to a pro-inflammatory stimulus, thereby recapitulating key stages of obesity progression. Three-dimensional spheroid organization of adipose cells was induced by culturing 3T3-L1 mouse preadipocytes on an elastin-like polypeptide-polyethyleneimine (ELP-PEI)-coated surface. Results indicate a more differentiated phenotype in 3D spheroid cultures relative to two-dimensional (2D) monolayer analogues based on triglyceride accumulation, CD36 and CD40 protein expression, and peroxisome proliferator-activated receptor-γ (PPAR-γ) and adiponectin mRNA expression. The 3T3-L1 adipocyte spheroid model was then used to test the effects of a pro-inflammatory microenvironment, namely maturation in the presence of elevated fatty acid levels followed by acute exposure to tumor necrosis factor alpha (TNF-α). Under these conditions, we demonstrate that metabolic function was reduced across all cultures exposed to TNF-α, especially so when pre-exposed to linoleic acid. Further, in response to TNF-α, enhanced lipolysis, monitored as increased extracellular glycerol and fatty acids levels, was observed in adipocytes cultured in the presence of exogenous fatty acids. Taken together, our 3D spheroid model showed enhanced adipogenic differentiation and presents a platform for elucidating the key phenotypic responses that occur in pro-inflammatory microenvironments that characterize obesogenic states.