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Although heparin can regulate angiogenesis, tumor growth and metastasis, its clinical application, as well as that of low‐molecular heparin (LMWH), for treating cancer are limited because of heparin's anticoagulant activity and risk of hemorrhages. LMWH‐taurocholate conjugates (LHT7), which have low anticoagulant activity, were synthesized. The structural property of LHT was evaluated by circular dichroism and the binding affinity of LHT7 to vascular endothelial growth factor 165 (VEGF165) was measured by isothermal titration calorimetry. The inhibitory effect of LHT7 on VEGF‐mediated KDR (VEGF‐receptor 2) phosphorylation in Human umbilical vein endothelial cells was evaluated. The VEGF165 dependent Matrigel plug assay was performed to verify the antiangiogenic potential of LHT7 on a VEGF165 inhibitor. Finally, tumor growth inhibition effects of LHT7 on SCC7 and the survival rate of animal models were investigated. Moreover, MDA‐MB231 xenograft mouse model was additionally used to confirm the therapeutic effect of LHT7 on human breast cancer cell line. As a result, LHT7 which has 12.7% of anticoagulant activity of the original LMWH showed a peculiar polyproline‐type helical structure. LHT7 binds to VEGF strongly and inhibits VEGF dependent KDR phosphorylation. The results of Matrigel plug assay proved LHT7 as a strong antiangiogenic agent inhibiting VEGF165. Remarkably, LHT7 showed a significant tumor growth inhibition potential on SCC7 with an increased survival rate. LHT7 also delayed tumor growth in MDA‐MB231 human breast cancer cell lines. © 2008 UICC

In this study, the potential of gold nanoparticles (20 nm) to deliver electrical stimulation to nerve cell cultures in vitro to induce nerve regeneration was evaluated. In order to use these biomaterials to deliver an electrical stimulus, we devised a novel method for the fabrication of a nanostructured 2D substrate comprising gold nanoparticles attached to the surface of a cover glass via an adsorption system. In this strategy, gold nanoparticles are created and then coated onto a positively charged cover glass that has been pretreated with polyethyleneimine (PEI). Scanning electron microscopy (SEM) revealed that the PC 12 cells extended neurites well on the gold nanoparticles in the presence of electrical stimulation. In addition, the neurite outgrowth of PC12 cells in response to pulsed and constant electrical stimulation was evaluated by live/dead cell determination, by reverse transcriptase polymerase chain reaction (RT-PCR) analysis, as well as by beta-tubulin and NF-200 expression. By electrical stimulation (250 mV for 1 h), PC12 cells with their neurite outgrowth length were highly increased, with a mean diameter of 98.5 microm. However, the neurite outgrowth length without electrical stimulation was approximately 10 approximately 20 microm. Moreover, the alternating current stimulation also showed good viability (<90%), while a high amount of cell death (more than 30%) was observed with constant current stimulation. Thus, the gold nanoparticles with pulsed current stimulation may provide suitable tools for the nerve regeneration using neuronal cells.