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To elucidate the mechanisms of nuclear estrogen receptor (ER)-mediated and G protein-coupled receptor 30 (GPR30)-mediated signaling in the regulation of proliferation in ER-positive and ER-negative endometrial cancer cells, two human endometrial carcinoma cell lines, Ishikawa (ER-positive) and KLE (ER-negative), were used. PCR and Western blot analyses were used to determine the effects of estrogen stimulation on the activation of Notch and GPR30-PI3K/AKT signaling. Cell growth was investigated using MTT assays. Overexpression of ER in ER-negative cells was achieved by plasmid transfection and was used to investigate the effects on cellular growth and Notch signaling. GPR30-mediated signaling was evaluated using siRNA interference. Estrogen stimulated cell proliferation in both cell lines, it activated Notch signaling in ER-positive Ishikawa cells, but not in ER-negative KLE cells. Blockade of this signaling by a Notch inhibitor resulted in partial arrest of estrogen-induced cell proliferation in Ishikawa cells. Overexpression of ER in KLE cells restored estrogen-enhanced Notch signaling and further promoted cell growth. GPR30, as a new G-protein-coupled estrogen receptor, was detected in both cell lines, but was stronger in ER-negative KLE cells. Depletion of GPR30 in KLE cells abolished estrogen-induced PI3K/AKT signaling activation and resulted in inhibition of cell proliferation. Conclusively, regulation of proliferation in nuclear ER-positive endometrial cancer cells is mediated by both ER-Notch signaling and GPR30-PI3K/AKT signaling, whereas only the latter pathway is involved in the regulation of growth in nuclear ER-negative endometrial cancer cells.

Bone morphogenesis proteins (BMPs) are one of the potent bone-forming factors. However, the safety, utility, and cost effectiveness of BMPs must be considered. Nowadays, there has been substantial interest in developing a chemical compound that safely promotes bone formation and facilitates fracture repair. Based on previous research with high throughout screening assay, we found one potent osteogenic inductive compound, named as OIC-A006 (Osteogenic inducible compound-active 006), which is classified in the amine family. In this study, we aimed to investigate the inducing effects of OIC-A006 on osteogenesis by bone marrow stem cells (BMSCs) in vitro and in vivo. We demonstrated that OIC-A006, at different concentrations, especially at optimal concentration of 6.25 microM, could stimulate BMSCs to express alkaline phosphatase (ALP), core-binding factor a1 (Cbfa1), osteopontin (OPN) and osteocalcin (OC), and to form calcified nodules in vitro. Under the bone tissue culture conditions, OIC-A006 also stimulated new bone formation of murine calvarial and metatarsal bone, indicating that OIC-A006 may exert positive effects on osteogenesis. Furthermore, to elucidate the in vivo osteogenic potential of OIC-A006, we used a rabbit skull defect model treated with sustained release microcapsules (OIC-A006/PLGA-MC) injected s.c. adjacent to the defect. These results revealed, for the first time, that OIC-A006 has the potential to promote osteogenesis in vitro and in vivo. This new compound may provide a new alterative agent for growth factors to promote bone healing and bone regeneration.

By using moving split-window techniques (MSWT), this study estimated how far the edge effects penetrated the forest and agricultural fields in the arid valley of upper reaches of Minjiang River, southwestern China. Its aim was to provide general information on vegetation along edge to interior gradients in order to assist in interpretation and prediction of biological phenomena associated with agriculture-forestry boundary, and to improve current management practices in such areas. Three types of boundaries (10 transects) were investigated and sampled. The results showed that when the window width reached 6-10, the change of the SED curve on the graph tended to become stable, and one or two peaks occurred. The depth of edge influence was clearly different for different types of boundaries, and could be estimated within 50 m from the edge to interior. The depth of edge influence (DEI) on vegetation diversity almost varied between 12-30 m, mainly depending on the patch type, topography and microclimate, but seldom on slope orientation. Of the 6 forest transects in the three types of boundaries, the DEI was detected only in the forest part transects M2 and M6, but almost detectable in the agricultural part of all transects. MSWT was considered to be a useful tool for characterizing edge dynamics if enough data was available, and became a simple and powerful technique for analyzing the boundary. The results will provide further knowledge for understanding the interaction between forestry and agriculture in the arid valley.

Objective: To investigate the probabilities of core-biding factor a1 (Cbfa1) expression by human skin fibroblasts induced in vitro., Methods: The fibroblasts were isolated, purified from human skin, and were grown in incubation in the media of TNF-alpha, BMP-2, and combined TNF-alpha and BMP-2 at certain concentrations, respectively. The changes in biological features of these fibroblasts correlated with osteogenesis were detected by immunohistochemistry and RT-PCR assay., Results: TNF-alpha could switch phenotype of collagen in fibroblasts from Type I and III to Type I and induce fibroblasts to express Ras and BMP type I receptor (BMPR-IA). TNF-alpha in combination with BMP-2 could induce fibroblasts to express Cbfa1 and osteocalcin mRNA., Conclusion: Human skin fibroblast could be induced into pro-osteoblast expressing Cbfa1, an osteoblast-specific transcription factor and a regulation of osteoblast differentiation, and combined use of TNF-alpha and BMP-2 was one of the regulating factors.