Involvement of chondroitin sulfate E in the liver tumor focal formation of murine osteosarcoma cells

Cell surface heparan sulfate plays a critical role in regulating the metastatic behavior of tumor cells, whereas the role of chondroitin sulfate/dermatan sulfate (CS/DS) has been little understood in this context. Here, we characterized CS/DS chains from the murine osteosarcoma cell line LM8G7, which forms tumor nodules in liver. Structural analysis of the CS/DS chains showed a higher proportion of GlcUAβ1-3GalNAc(4,6-O-disulfate) (E-units) in LM8G7 (12%) than in its parental cell line LM8 (6%), which rarely forms tumors in the liver. Immunostaining with GD3G7, an antibody specific to E-units, confirmed the higher expression of the epitope in LM8G7 than LM8 cells. The tumor focal formation of LM8G7 cells in the liver in mice was effectively inhibited by the pre-administration of CS-E (rich in E-unit) or the pre-incubation of the antibody GD3G7 with the tumor cells. CS-E or GD3G7 inhibited the adhesion of LM8G7 cells to a laminin-coated plate in vitro. In addition, the invasive ability of LM8G7 cells in vitro was also reduced by the addition of CS-E or the antibody. Further, CS-E or the antibody inhibited the proliferation of LM8G7 cells dose-dependently. The binding of LM8G7 cells to VEGF in vitro was also significantly reduced by CS-E and GD3G7. Thus, the present study reveals the significance of highly sulfated CS/DS structures in the liver colonization of osteosarcoma cells and also provides a framework for the development of GAG-based anti-cancer molecules

A small oxazine compound as an anti-tumor agent: A novel pyranoside mimetic that binds to VEGF, HB-EGF, and TNF-α

A novel pyranoside mimetic compound, DMBO (2-(2,6-difluorophenyl)-5-(4-methoxyphenyl)-1-oxa-3-azaspiro5.5undecane), was designed and synthesized. The sugar mimicking behavior of DMBO was addressed by its ability to bind several growth factors/cytokines such as vascular endothelial growth factor (VEGF), heparin-binding epidermal growth factor-like growth factor (HB-EGF), and tumor necrosis factor (TNF)-α as demonstrated by the recently developed surface plasmon resonance assay. DMBO exhibited strong anti-proliferation activity in vitro against tumor cells including a highly metastatic murine osteosarcoma cell line LM8G7 that secretes VEGF as well as two human ovarian cell lines, OVSAHO and SKOV-3, which secrete TNF-α and HB-EGF respectively. Furthermore, DMBO inhibited the metastatic activity to the mouse liver of LM8G7 cells injected from a lateral tail vein, and affected the heparan-degrading activity of LM8G7 cells. Here, we report that DMBO acts as a human heparanase inhibitor in vitro possibly as a substrate mimetic. DMBO also inhibited the migration and invasion of LM8G7 cells and angiogenic events such as endothelial cell proliferation, migration and capillary tube-like formation in vitro. More prominently, the administration of DMBO with heparin resulted in synergistic anti-tumor effects in mouse modelofosteosarcoma. These preclinical data shows the potential anti-cancer effects of DMBO

Sintering Mechanisms of High-Performance Garnet-type Solid Electrolyte Densified by Spark Plasma Sintering

Garnet-type solid electrolyte Li6.5La3Zr1.5Ta0.5O12 (LLZT) was densified by using a spark plasma sintering (SPS) technique. Formation of impurities in the obtained pellets was studied in detail. It is revealed that impurities are strongly related to the SPS process: electrolysis of LLZT and electromigration of graphite. The electrolysis results in La2Zr2O7 on anode of the SPS process, which is accompanied by reduction of Li2CO3 to amorphous carbon on cathode. The electrolysis on SPS could be successfully suppressed by employing LLZT powder without Li2CO3. When these impurities were removed, pellets obtained by SPS exhibited electrochemical performance comparable with those densified by other methods total ionic conductivity of 6.9 × 10?4 S cm?1 at 298 K and short-circuit prevention up to 100 μA cm?2 on dc polarization. The results confirm great advantage of SPS on manufacturing the dense garnet-type solid electrolytes: a low-temperature (900?1100 °C) and short-sintering-time process (10 min)