Extracellular Metabolic Energetics Can Promote Cancer Progression Investigators have identified the extracellular space as an important compartment for malignant energetic catalysis and therapeutic targeting. By functionally screening 661 microRNAs (miRNAs) in parallel during liver colonization, they identified miR-551a and miR-483 as robust endogenous suppressors of liver colonization and metastasis. [Cell] Abstract | Graphical Abstract Actin-Delimited Adhesion-Independent Clustering of E-Cadherin Forms the Nanoscale Building Blocks of Adherens Junctions Investigators found that loosely organized clusters of approximately five E-cadherin molecules that form independently of cis or trans interactions, and that are delimited by the cortical F-actin meshwork, are the precursors of trans-ligated adhesive clusters that make up the adherens junction. [Dev Cell] Abstract | Graphical Abstract | Press Release Heparan Sulfate Proteoglycans Regulate Fgf Signaling and Cell Polarity during Collective Cell Migration Analysis of mutations in two exostosin glycosyltransferase genes revealed that loss of heparan sulfate chains results in a failure of collective cell migration due to enhanced fibroblast growth factor (Fgf) ligand diffusion and loss of Fgf signal transduction. [Cell Rep] Full Article | Graphical Abstract Ligand-Occupied Integrin Internalization Links Nutrient Signaling to Invasive Migration Scientists show that α5β1 integrin undergoes tensin-dependent centripetal movement from the cell periphery to populate adhesions located under the nucleus. From here, ligand-engaged α5β1 integrins are internalized under control of the Arf subfamily GTPase, Arf4, and are trafficked to nearby late endosomes/lysosomes. [Cell Rep] Full Article | Graphical Abstract Development of a Cellularly Degradable PEG Hydrogel to Promote Articular Cartilage Extracellular Matrix Deposition A poly (ethylene glycol) (PEG) norbornene hydrogel was functionalized with thiolated transforming growth factor β1 and cross-linked by a matrix metalloproteinase-degradable peptide. Chondrocytes were co-encapsulated with a smaller population of mesenchymal stem cells, with the goal of stimulating matrix production and increasing bulk mechanical properties of the scaffold. [Adv Healthc Mater] Abstract PDGF-Stimulated Dispersal of Cell Clusters and Disruption of Fibronectin Matrix on 3D Collagen Matrices Requires Matrix Metalloproteinase-2 Previously, researchers reported that under procontractile culture conditions, fibronectin fibrillar matrix assembly by human fibroblasts functioned as a nucleation center for cell clustering on 3D collagen matrices. They now report that switching preformed cell clusters from procontractile to promigratory culture conditions results in cell dispersal out of clusters and disruption of FN matrix. [Mol Biol Cell] Abstract | Full Article Matrix-Specific Anchors: A New Concept for Targeted Delivery and Retention of Therapeutic Cells Researchers engineered an artificial collagen-specific anchor (ACSA) that is able to specifically bind collagen I. They demonstrate that, in comparison to the control, the cells expressing the ACSA attached better to collagen I and exhibited improved retention in sites of seeding. [Tissue Eng Part A] Abstract Incorporation of a Prolyl Hydroxylase Inhibitor into Scaffolds: A Strategy for Stimulating Vascularization Scientists conjugated the prolyl hydroxylase inhibitor pyridine-2,4-dicarboxylic acid (PDCA) through amide bonds to a gelatin sponge (Gelfoam®). Fibroblasts cultured on PDCA-Gelfoam were able to infiltrate and proliferate in these scaffolds while secreting significantly more vascular endothelial growth factor than cells grown on Gelfoam without PDCA. [Tissue Eng Part A] Abstract |