Project description:Epithelial-Mesenchymal Transition (EMT) is essential for tissue patterning and organization. It involves both regulation of cell motility and alterations in the composition and organization of the extracellular matrix (ECM); a complex environment of proteoglycans and fibrous proteins that promotes tissue homeostasis, regulates signaling in response to chemical and biomechanical stimuli and is often dysregulated in diseases such as cancer and fibrosis. Here, we demonstrate that Basonuclin-2 (BNC2), a mesenchymal-expressed gene that has been widely associated with cancer and developmental defects by genome-wide association study (GWAS), is a novel regulator of ECM composition and degradation. We find that at endogenous levels, BNC2 controls the expression of specific collagens, matrix metalloproteases and other matrisomal components in breast cancer cells, and in fibroblasts that are primarily responsible for the deposition and processing of the ECM within the tumour microenvironment. In so doing, BNC2 modulates the motile and invasive properties of cancers which likely explains the association of high BNC2 expression with increasing cancer grade and poor patient prognosis.
Project description:Visual processing depends on sensitive and balanced synaptic neurotransmission. Extracellular matrix proteins in the environment of cells are key modulators in synaptogenesis and synaptic plasticity. In the present study, we provide evidence that the combined loss of the four extracellular matrix components brevican, neurocan, tenascin-C and tenascin-R in quadruple knockout mice leads to severe retinal dysfunction and diminished visual motion processing in vivo. Remarkably, impaired visual motion processing was accompanied by a developmental loss of cholinergic direction-selective starburst amacrine cells. Additionally, we noted imbalance of inhibitory and excitatory synaptic signaling in the quadruple knockout retina. Collectively, the study offers novel insights into the functional importance of four key extracellular matrix proteins for retinal function, visual motion processing and synaptic signaling.
Project description:This project used a quantitative proteomics approach to study the molecular mechanism in regulating the production of extracellular matrix proteins by mesenchymal cells
Project description:The metabolic state of a cell is influenced by cell-extrinsic factors, including nutrient availability and growth factor signaling. Here, we present extracellular matrix (ECM) remodeling as another fundamental node of cell-extrinsic metabolic regulation. Unbiased analysis of glycolytic drivers identified the hyaluronan-mediated motility receptor as among the most highly correlated with glycolysis in cancer. Confirming a mechanistic link between the ECM glycosaminoglycan hyaluronan and metabolism, treatment of both cells and xenograft tumors with hyaluronidase (HAase) triggers a robust increase in glycolysis. This is largely achieved through rapid receptor tyrosine kinase-mediated induction of mRNA decay factor ZFP36, which targets TXNIP transcripts for degradation. Since TXNIP promotes internalization of the glucose transporter GLUT1, its acute decline enriches GLUT1 at the plasma membrane. Functionally, induction of glycolysis by HAase is required for concomitant acceleration of cell migration. This interconnection between ECM remodeling and metabolism is exhibited in dynamic tissues states including tumorigenesis and embryogenesis.
Project description:Cholangiocarcinoma (CCA) is a hepatobiliary malignancy with dismal prognosis. Currently available models fail to recapitulate the full complexity of CCA, particularly the desmoplastic environment and the interplay between cancer cells and the extracellular matrix (ECM). We aimed to study the role of epithelial tumor cells in ECM deposition and desmoplasia by designing a model encompassing primary epithelial CCA organoids (CCAOs) and native liver and tumor scaffolds obtained by decellularization Background & Aims: Cholangiocarcinoma (CCA) is a hepatobiliary malignancy with dismal prognosis. Currently available models fail to recapitulate the full complexity of CCA, particularly the desmoplastic environment and the interplay between cancer cells and the extracellular matrix (ECM). We aimed to study the role of epithelial tumor cells in ECM deposition and desmoplasia by designing a model encompassing primary epithelial CCA organoids (CCAOs) and native liver and tumor scaffolds obtained by decellularization. Results: Decellularization resulted in effective removal of cells while preserving ECM structure and retaining important characteristics of the tissue origin. When culturing CCAOs in CCA-M, compared to TFL-M and BME, the genome-wide gene expression profile much more resembled the transcriptome of primary CCA tumor tissue in vivo, with an accompanying increase in chemoresistance. CCAOs in decellularized matrix, both CCA-M and TFL-M, exhibited the formation of complex morphological structures, and revealed environment-dependent proliferation and migration dynamics, driven by the occurrence of epithelial-mesenchymal transition (EMT). CCA-M induced specific extracellular matrix protein production in CCAOs, such as fibronectin 1 (FN1), which is related to desmoplasia and patient survival. In TFL-M, lacking the desmoplastic environment, CCAOs were able to initiate a desmoplastic reaction directly through increased production of multiple collagen types. Conclusions: This improved model of cholangiocarcinoma, combining organoids and native extracellular matrix, recapitulates key components of CCA tumor biology, including transcriptome profiles, migration patterns, EMT, and ECM protein production. The increased production of extracellular matrix proteins suggests that epithelial tumor cells can contribute to their own desmoplastic environment.