Availability of Extracellular Matrix Biopolymers and Differentiation State of Human Mesenchymal Stem Cells Determine Tissue-Like Growth In Vitro To explore the space-filling growth of adherent mesenchymal stem cells (MSC) into tissue-like structures in vitro, human bone marrow derived MSC were exposed to fibronectin-coated, millimeter-sized, triangular channels casted in poly(dimethyl siloxane) carriers. [Biomaterials] Abstract Presence of Insulin-Like Growth Factor Binding Proteins Correlates with Tumor-Promoting Effects of Matrix Metalloproteinase 9 in Breast Cancer Scientists compared stromal components of a luminal and a triple-negative/basal-like genetically engineered breast cancer mouse model. The types of cytokines and their expression levels were very different in the two models, as was the extent of innate immune cell infiltration; however, both models showed infiltration of innate immune cells that expressed matrix metalloproteinase 9, an extracellular protease linked to the progression of many types of cancer. [Neoplasia] Full Article | Press Release Three-Dimensional Cage-Like Microscaffolds for Cell Invasion Studies During the invasive process, tumor cells must pass through the extracellular matrix, whose structural and mechanical properties define the parameters of the migration process. Investigators propose three-dimensional-complex cage-like microstructures, realized by two-photon direct laser writing, to analyze cell migration through pores significantly smaller than the cell nucleus. [Sci Rep] Full Article Partially Digested Adult Cardiac Extracellular Matrix Promotes Cardiomyocyte Proliferation In Vitro Investigators hypothesized that partial digestion of adult extracellular matrix (ECM) would liberate less crosslinked components that promote cardiomyocyte proliferation, similar to fetal ECM. [Adv Healthc Mater] Abstract Severe Extracellular Matrix Abnormalities and Chondrodysplasia in Mice Lacking Collagen Prolyl 4-Hydroxylase Isoenzyme II in Combination with a Reduced Amount of Isoenzyme I To assess possible functional complementarity, scientists established P4ha1+/-;P4ha2-/- mice. The columnar arrangement of proliferative chondrocytes was impaired, the amount of 4-hydroxyproline and the Tm of collagen II were reduced and the extracellular matrix was softer in the growth plates of newborn P4ha1+/-;P4ha2-/- mice. [J Biol Chem] Abstract | Full Article Artificial Extracellular Matrices Support Cell Growth and Matrix Synthesis of Human Dermal Fibroblasts in Macroporous 3D Scaffolds Coatings with artificial extracellular matrix, consisting of the structural protein collagen I and the glycosaminoglycan hyaluronan (HA) or sulphated HA derivatives, were investigated for their applicability in a three-dimensional (3D) system. [J Tissue Eng Regen Med] Abstract Role of α1 and α2 Chains of Type IV Collagen in Early Fibrotic Lesions of Idiopathic Interstitial Pneumonias and Migration of Lung Fibroblasts Researchers studied the expression of type I and III collagen and all α chains of type IV collagen in lung specimens from patients with usual interstitial pneumonia (UIP) or organizing pneumonia (OP) via immunohistochemistry. Although they observed type I and III collagens in early fibrotic lesions of both UIP and OP, they found type IV collagen, especially α1 and α2 chains, in early fibrotic lesions of UIP but not OP. [Lab Invest] Abstract The Hepatocyte Growth Factor Receptor as a Potential Therapeutic Target for Dedifferentiated Liposarcoma Scientists found that the in vitro stimulation of dedifferentiated liposarcomas cells with hepatocyte growth factor elevated the degree of PI3K/AKT and MAPK pathway signaling, and that pro-tumorigenic phenotypes such as cell proliferation, invasion, and migration were significantly enhanced. [Lab Invest] Abstract The BRAFV600E Inhibitor, PLX4032, Increases Type I Collagen Synthesis in Melanoma Cells The authors document that blocking the Ras-Raf-Mek-Erk MAPK pathway, either with an ERK (PLX4032) or a MEK signaling inhibitor, in BRAFV600E human and murine melanoma cell lines increases collagen synthesis in vitro and collagen deposition in vivo. Since TGFβ signaling is a major mediator of collagen synthesis, they examined whether blocking TGFβ signaling with a small molecule inhibitor would block this increase in collagen. [Matrix Biol] Full Article | Press Release Skin Physiology in Microgravity: A Three-Month Stay aboard ISS Induces Dermal Atrophy and Affects Cutaneous Muscle and Hair Follicles Cycling in Mice Mice were maintained in the Mice Drawer System for 91 days aboard the International Space Station (ISS). Skin specimens were collected shortly after landing for morphometric, biochemical, and transcriptomic analyses. A significant reduction of dermal thickness was observed accompanied by an increased newly synthesized procollagen, likely reflecting an increased collagen turnover. [npj Microgravity] Full Article | Press Release |