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Abstract: Epidermal growth factor receptor (EGFR) plays an important role in gastric cancer (GC) progression. Our previous data demonstrated that type II cGMP‐dependent protein kinase (PKG II) could block the EGF‐EGFR axis as well as down‐stream signaling pathways, for example, MAPK, PI3 K, and PLC in GC cells. However, the exact mechanisms of PKG II against cancer remain unclear. Therefore, the present work was to address the above question. Human GC cell line AGS was infected with adenoviral construct encoding cDNA of PKG II (Ad‐PKG II) to up‐regulate PKG II and then treated with 8‐pCPT‐cGMP. Two‐dimensional electrophoresis (2‐DE) was used to analyze the changes of protein expression in the cells. The results showed that 17 proteins had more than twofold changes in EGF‐treated group compared with control. However, Ad‐PKG II could effectively reversed the changes. Furthermore, far upstream element‐binding protein 1 (FUBP1) and MarvelD3 were chosen and PKG II activation reversed EGF/EGFR‐induced up‐regulation of FUBP1 and downregulation of MarvelD3, respectively. MarvelD3 silence effectively abolished the inhibitory effect of PKG II on EGF‐triggered migration. These data indicated that the inhibitory effect of PKG II partially was associated with MarvelD3. [ABSTRACT FROM AUTHOR]

Abstract: Mesenchymal stem cells (MSCs) are known as a population of multi-potential cells able to proliferate and differentiate into multiple mesodermal tissues including bone, cartilage, muscle, ligament, tendon, fat and stroma. In this study human MSCs were successfully isolated from the umbilical cords. The research characteristics of these cells, e.g., morphologic appearance, surface antigens, growth curve, cytogenetic features, cell cycle, differentiation potential and gene expression were investigated. After 2weeks of incubation, fibroblast-like cells appeared to be dominant. During the second passage the cells presented a homogeneous population of spindle fibroblast-like cells. After more than 4months (approximately 26 passages), the cells continued to retain their characteristics. Flow cytometry analysis revealed that CD29, CD44, CD95, CD105 and HLA-I were expressed on the cell surface, but there was no expression of hematopoietic lineage markers, such as CD34, CD38, CD71 and HLA-DR. Chromosomal analysis showed the cells kept a normal karyotype. The cell cycle at the third passage showed the percentage of G0/G1, G2/M and S phase were 88.86%, 5.69% and 5.45%, respectively. The assays in vitro demonstrated the cells exhibited multi-potential differentiation into osteogenic and adipogenic cells. Both BMI-1 and nucleostemin genes, expressed in adult MSCs from bone marrow, were also expressed in umbilical cord MSCs. Here we show that umbilical cords may be a novel alternative source of human MSCs for experimental and clinical applications. [Copyright &y& Elsevier]