19 research outputs found
Perlecan/Hspg2 Deficiency Alters the Pericellular Space of the Lacunocanalicular System Surrounding Osteocytic Processes in Cortical Bone
Osteocytes project long, slender processes throughout the mineralized matrix of bone, where they connect and communicate with effector cells. The interconnected cellular projections form the functional lacunocanalicular system, allowing fluid to pass for cell-to-cell communication and nutrient and waste exchange. Prevention of mineralization in the pericellular space of the lacunocanalicular pericellular space is crucial for uninhibited interstitial fluid movement. Factors contributing to the ability of the pericellular space of the lacunocanalicular system to remain open and unmineralized are unclear. Immunofluorescence and immunogold localization by transmission electron microscopy demonstrated perlecan/Hspg2 signal localized to the osteocyte lacunocanalicular system of cortical bone, and this proteoglycan was found in the pericellular space of the lacunocanalicular system. In this study we examined osteocyte lacunocanalicular morphology in mice deficient in the large heparan sulfate proteoglycan perlecan/Hspg2 in this tissue. Ultrastructural measurements with electron microscopy of perlecan/Hspg2-deficient mice demonstrated diminished osteocyte canalicular pericellular area, resulting from a reduction in the total canalicular area. Additionally, perlecan/Hspg2-deficient mice showed decreased canalicular density and a reduced number of transverse tethering elements per canaliculus. These data indicated that perlecan/Hspg2 contributed to the integrity of the osteocyte lacunocanalicular system by maintaining the size of the pericellular space, an essential task to promote uninhibited interstitial fluid movement in this mechanosensitive environment. This work thus identified a new barrier function for perlecan/Hspg2 in murine cortical bone. © 2011 American Society for Bone and Mineral Research
Clinicopathologic analysis and syndecan-1 and Ki-67 expression in calcifying cystic odontogenic tumors, dentinogenic ghost cell tumor, and ghost cell odontogenic carcinoma
Endometrial Cells Get Side-Tracked: Side Population Cells Promote Epithelial-Mesenchymal Transition in Endometrial Carcinoma
This Commentary reports on the role of endometrial carcinoma side population cells in epithelial-mesenchymal transition
Clinical significance of decreased nidogen-2 expression in the tumor tissue and serum of patients with hepatocellular carcinoma
Enhanced stromal syndecan-1 expression is an independent risk factor for poor survival in bladder cancer.
In this study, we assessed the changes and prognostic relevance of syndecan-1 (SDC1) tissue and serum levels in bladder cancer (BC). SDC1 levels were analyzed in 213 samples (119 paraffin-embedded and 79 serum samples of BC patients and 15 controls) using immunohistochemistry and enzyme-linked immunosorbent assay. Results were correlated with clinicopathological characteristics and follow-up data, as well as previously determined serum levels of angiogenic factors (basic fibroblast growth factor, endostatin, angiostatin, angiopoietin, vascular endothelial growth factor, Tie2 and MMP-7). SDC1 staining was present in the cell membrane of normal bladder epithelium and non-muscle-invasive BC cells but was absent in a significant proportion of muscle-invasive carcinomas (P < .001). In contrast, stromal SDC1 expression was enhanced in muscle-invasive compared to non-muscle-invasive BCs (P = .001). Serum concentrations of the SDC1 ectodomain were higher in muscle-invasive BCs compared to controls or non-muscle-invasive carcinomas (P < .001 each). Lymph node-positive cases had the highest SDC1 serum concentrations (P < .001). SDC1 expression in stromal cells was independently associated with survival (hazard ratio = 2.034, 95% confidence interval 1.176-3.519, P = .011). SDC1 serum concentrations correlated with those of endostatin and matrix metalloproteinase 7. Loss of SDC1 in tumor cells and the parallel increase of serum SDC1 ectodomain concentration in high-stage, high-grade BCs suggest the involvement of SDC1 shedding in BC progression. In addition, high preoperative SDC1 serum levels may help to identify patients with lymph node metastases, supporting therapeutic decision-making. Presence of SDC1 in tumor stroma is an independent risk factor for patient survival and may therefore be used to select patients for more aggressive therapy