Chen R.,Sun Yat Sen University |
Chen R.,Key Laboratory for Stem Cells and Tissue Engineering |
Chen J.,Sun Yat Sen University |
Chen J.,Key Laboratory for Stem Cells and Tissue Engineering |
And 14 more authors.
Toxicology Mechanisms and Methods | Year: 2010
The new EU legislations for cosmetics (Seventh Amendment) have laid down deadlines for the replacement of animal tests in cosmetics. This policy stimulates the acceptance of in vitro approaches to test embryotoxic potentials of compounds in cosmetics products. The embryonic stem cell test (EST) designed by The European Centre for the Validation of Alternative Methods (ECVAM) is currently the most promising in vitro assay to predict the embryotoxic potential of compounds. In this study, six selected compounds (hydroquinone, eugenol, dibutyl phthalate, antimony (III) oxide, neodymium (III) nitrate hydrate, melamine) formerly involved in cosmetic products were selected to test their embryotoxic potentials by the EST. 5-Fluorouracil and penicillin G were separately set as positive and negative control. The embryotoxic potential was determined by the prediction model (PM), which was calculated from three endpoints, the IC50 3T3, IC50 ES, and ID50. Hydroquinone, eugenol, and antimony (III) oxide indicated with strong embryotoxicity, while dibutyl phthalate, neodymium (III) nitrate hydrate, and melamine exhibited a weak embryotoxicity. These results may provide a valuable attempt to expand the application of EST to the cosmetics field. © 2010 Informa UK Ltd.
Chen Z.,Sun Yat Sen University |
Wang T.,Sun Yat Sen University |
Wang T.,Key Laboratory for Stem Cells and Tissue Engineering |
Luo H.,Sun Yat Sen University |
And 13 more authors.
Human Pathology | Year: 2010
Stem cell marker nestin has been reported to be activated in various neoplasms, and its expression is correlated with poor prognosis. However, nestin expression in non-small cell lung cancer still remains unclear. The present study aimed to investigate nestin expression in 52 tissue samples of non-small cell lung cancer by immunohistochemical staining and explore its correlation with some clinicopathologic characteristics. The associations of nestin with lymphatic vessel density, microvessel density, vascular endothelial growth factor, vascular endothelial growth factor-C, and cyclooxygenase-2 (COX-2) were further observed to determine the linkage between nestin and lymphangiogenesis. The results showed that nestin expressed in tumor cells of 45 samples. High nestin expression correlated significantly with poor differentiation (P = .007), adenocarcinoma (P = .000), N2 lymph node metastasis (P = .006), high microvessel density (P = .033), and lymphatic vessel density (P = .020). Multivariate analysis of N1 and N2 lymph node metastasis revealed a 1.086-fold increase in hazard ratio of N2 lymph node involvement (P = .011) in patients with high nestin expression in primary tumor. More important, multivariate analysis showed a significant correlation of lymphatic vessel density with nestin and vascular endothelial growth factor-C expression (P = .039 and P = .045), independent of vascular endothelial growth factor, COX-2, and other clinicopathologic characteristics. The results demonstrated that nestin expressed in most tumor cells of non-small cell lung cancer tissue and had a direct linkage to lymph node metastasis and tumor-induced lymphangiogenesis, independent of COX-2 signal pathway. © 2010 Elsevier Inc. All rights reserved.
Li W.,Sun Yat Sen University |
Li W.,Key Laboratory for Stem Cells and Tissue Engineering |
Liu C.,Sun Yat Sen University |
Liu C.,Key Laboratory for Stem Cells and Tissue Engineering |
And 16 more authors.
Cell Transplantation | Year: 2010
Embryonic stem (ES) cells have the ability to undergo indefinite self-renewal in vitro and give rise during development to derivatives of all three primary germ layers (ectoderm, endoderm, and mesoderm), which make them a highly prized reagent in cell and gene therapy. Efficient introduction of various genes of interest into primate ES cells has proven to be difficult. Here, we demonstrated that the self-inactivating HIV-1-based lentiviral vectors constructed by MultiSite gateway technology are efficient tools for the transduction of cynomolgus monkey (Macaca fasicularis) ES (cmES) cells. After antibiotic selection, all of the transduced cells can stably express the reporter gene (humanized Renilla GFP or dTomato) while maintaining their stem cell properties, including continuous expression of stem cell markers, alkaline phosphatase (AKP), OCT-4, SSEA-4, and TRA-1-60, formation of embryoid bodies in vitro and teratomas in vivo containing derivatives of three embryonic germ layers. This approach will provide a useful tool for both gene function studies and in vivo cell tracking of stem cells. Copyright © 2010 Cognizant Comm. Corp. All rights reserved.