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21.
ZHAO Xue-rong WANG Jian-ping XIAO Li-jun XU Qian ZHAO En-hong ZHENG Xin ZHENG Hua-chuan ZHAO Shuang 《园艺学报》2015,31(1):98-103
AIM: To investigate the effects of 17-AAG on apoptosis and cell cycle of HCT-15 cells and to clarify the related mechanisms. METHODS: MTT method was employed to evaluate the inhibitory effects of 17-AAG with Aifferent time and different doses on the proliferation of HCT-15 cells. The cells were stained with Annexin V-FITC/propidiumiodide and measured by flow cytometry. The expression of STAT3, cyclin D1, Cyt C, caspase 9 and caspase 3 at mRNA and protein levels was determined by RT-PCR and Western blotting. RESULTS: Treatment with 17-AAG at concentration of 1.25~20 mg/L for 24 h and 48 h significantly inhibited the activity of HCT-15 cells at both time-and concentration-dependent manners. Treatment with 17-AAG at concentrations of 0.425, 0.85 and 1.7 mg/L for 48 h significantly induced apoptosis and cell cycle arrest of HCT-15 cells. The exposure of 17-AAG at concentrations of 0.425, 0.85 and 1.7 mg/L for 48 h to the HCT-15 cells significantly down-regulated the expression of STAT3 and cyclin D1 at mRNA and protein levels, but up-regulated Cyt C, caspase 9 and caspase 3 mRNA and protein in a concentration-dependent manner. CONCLUSION: 17-AAG inhibits the cell activity, induces apoptosis and G1 arrest by down-regulating the expression of cyclin D1, and promoting the mitochondria apoptosis through STAT3 pathway. 相似文献
22.
AIM: To compare the expression of SIRT2 in ovarian surface epithelial (OSE) cell line and serous ovarian carcinoma (SOC) cell lines, and to investigate the effects of SIRT2 on the cell proliferation, migration and invasion. METHODS: The expression levels of SIRT2 in the OSE cell line and the SOC cell lines were determined by Western blot. The SIRT2 siRNAs and overexpression construct were designed and verified. Transient transfection of SIRT2 siRNAs or overexpression construct was performed, and the effect of SIRT2 on the cell proliferation, migration and invasion was evaluated. RESULTS: SIRT2 levels in the 5 strains of SOC cell lines were significantly lower than that in the OSE cell line. SIRT2 knockdown in HOSEpiC cells significantly enhanced the ability of cell colony formation and accelerated the cell growth rate. On the contrary, overexpression of SIRT2 in HO8910 cells dramatically repressed the number of cell colonies and cell activity. SIRT2 significantly changed the ability of ovarian cell migration. Knockdown of SIRT2 facilitated the cell invasion. CONCLUSION: The expression of SIRT2 in the SOC cells is significantly down-regulated. In the OSE cells, SIRT2 acts as a tumor suppressor and mediates the inhibition of cell proliferation, migration and invasion. 相似文献
23.
AIM: To develop the cell model of polymer/liquid crystal and to study the effect of their elasticity on the adhesion of rat bone marrow mesenchymal stem cells (rBM-MSCs). METHODS: Using the method of solvent evaporation induced phase separation, the cell model of polymer/liquid crystal was constructed. The surface morphology and phase separation structure were determined by polarized optical microscopy (POM), scanning electron microscopy (SEM) and small angle X-ray scattering (SAXS). rBM-MSCs were separated and expanded by adherent culture. The surface markers of rBM-MSCs were detected by flow cytometry. The cells were induced to osteogenic differentiation and adipogenic differentiation for 2 weeks. After 3 passages, the cells were divided into 4 groups, including total PU control group, 10% membrane group, 30% membrane group and 50% membrane group. The cells were then incubated with rhodamine phalloidin for cytoskeleton staining and were observed under the confocal laser scanning microscope after cultured for 24 h. RESULTS: The cell model of polymer/liquid crystal was constructed successfully using the method of solvent evaporation induced phase separation. Flow cytometry results showed that the rBM-MSCs positively expressed CD29, CD44 and CD90, and negatively expressed CD34 and CD45. After stained with alizarin red S and oil red O, the calcium nodule and lipid droplets in rBM-MSCs were observed obviously. The cytoskeleton staining result indicated that the area in total PU control group, 10% membrane group and 30% membrane group were greater, and the actin microfilaments were also clearer than that in 50% membrane group. CONCLUSION: The cell model with suitable content of liquid crystal made a contribution to the rBM-MSCs' adhesion, but too much liquid crystal inhibits cell adhesion. 相似文献
24.
AIM: To investigate the effect of inhibiting myosin light chain kinase(MLCK) on endothelin-1(ET-1) induced proliferation and apoptosis of rat pulmonary artery smooth muscle cells(PASMCs). METHODS: Rat PASMCs were cultured and stimulated with ET-1. The cells were randomly divided into control group, ET-1 group and ET-1+MLCK inhibitor group(ET-1+M). Western blotting, MTT assay, [3H]-TdR incorporation and flow cytometry were employed to test the expression of myosin light chain(MLC) and MLCK, cell proliferation, cell cycle and apoptotic rate of PASMCs,respectively. The phosphorylation of MLC was determined by glycerol-PAGE coupled with Western blotting. RESULTS: Compared with control group, the protein expression of MLCK and MLC phosphorylation significantly enhanced after ET-1 stimulation. ET-1 markedly induced the proliferation and decreased the percentage of apoptotic rate in the PASMCs. However, pretreatment with ML-7, a MLCK inhibitor, significantly reversed the above effects induced by ET-1. CONCLUSION: MLCK inhibitor effectively inhibits the ET-1-induced proliferation and the cell cycle progression. 相似文献
25.
AIM: To investigate the expression of long non-coding RNA maternally expressed gene 3(MEG3) in colorectal cancer(CRC) cells, and to observe the effect of MEG3 on the invasion and migration of CRC cells. METHODS: The levels of MEG3 in human normal colon cell NCM460 and CRC cells SW48 and LoVo were detected by real- time PCR. MEG3 was over-expressed by plasmid transfection, and the effects of MEG3 on the invasion and migration of SW48 and LoVo cells were analyzed by Transwell assay and wound healing assay. The expression of matrix metalloproteinase(MMP) family proteins was determined by Western blotting. RESULTS: The level of MEG3 was down-regulated in CRC cells compared with normal colon cell NCM460. The invasion and migration of CRC cells were reduced after MEG3 over-expression. Transwell invasion and migration assays showed that the numbers of transmembrane SW48 and LoVo cells were smaller in MEG3 over-expression group than control group(CONCLUSION: The expression of MEG3 is down-regulated in CRC cells. Over-expression of MEG3 inhibits the invasion and migration of CRC cells. TIMP-2, MMP-2 and MMP-9 might play an important role in this regulation. 相似文献
26.
HUANG Yong-hong SHI Hui-mian ZHOU Xiao-yan XU Hong LUO Zhi-jun XU Fang-yun 《园艺学报》2015,31(7):1340-1344
Receptor type protein tyrosine phosphatase Q (PTPRQ) is an unusual protein tyrosine phosphatase that has intrinsic dephosphorylating activity for various phosphatidylinositiol and phospho-tyrosine substrates, especially the phosphatidylinositol activity. Recent data show that PTPRQ has an important role in various biological processes and is associated with some diseases. In this article, the structure and function of PTPRQ and the relationship between PTPRQ and diseases were briefly summarized. 相似文献
27.
AIM: To investigate the effect of Ikaros isoforms on the proliferation of human ovarian cancer SKOV3 cells. METHODS: Three isoforms of Ikaros, IK1, IK2 and IK6, were transfected into ovarian cancer SKOV3 cells. CCK-8 assay and cell counting were used to detect the effects of Ikaros isoforms on the proliferation of SKOV3 cells. The cell cycle was analyzed by flow cytometry. The cell cycle-related proteins were detected by Western blot. RESULTS: IK1 and IK2 expression inhibited SKOV3 cells proliferation. Flow cytometry analysis indicated that IK1 and IK2 induced SKOV3 cell cycle arrest at the G1 phase. IK6 isoform exerted no obvious effect on the proliferation or cell cycle of SKOV3 cells. Compared with control EV group, IK1 group and IK2 group showed a dramatic elevation in the expression of the cell cycle inhibitor p21, along with a substantial decrease in the expression of the cell cycle inducers cyclin D1 and cyclin D2, which did not change in IK6 group. CONCLUSION: IK1 and IK2 significantly inhibit the proliferation of ovarian cancer SKOV3 cells and induce cell cycle arrest at G1 phase by regulation of cell cycle-related proteins cyclin D1, cyclin D2 and p21, while IK6 isoform exerts no obvious effect on the proliferation and cell cycle of SKOV3 cells. 相似文献
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Kenaf (Hibiscus cannabinus) plants are widely known for their contribution to the global and regional environment because of their ability to fix CO2. On the other hand, some scientists have doubts about CO2 fixation by kenaf and have misgivings about the effect of kenaf on the ecosystem. We have characterized the structural characteristics
of cell walls of bast fibers, cores, roots, and leaves of kenaf during the maturation of plants and investigated the rate
of photosynthesis. During maturation of the kenaf plant the cellulose (bast fiber 52–59%, core 44–46%) and lignin (bast fiber
9.3–13.2%, core 18.3–23.2%) contents increased significantly. The aromatic composition of the lignin of bast fiber was significantly
different from that of the core lignin and of other plants. The lignin of bast fiber appears similar to pure syringyl lignin.
Fixation of CO2 by kenaf plants and their contribution to the global environment are discussed. A significatly high rate of photosynthesis
of kenaf plants was observed compared to that of woody plants in Japan, but the amount of CO2 fixation depends on the characteristics of the plantation. If the kenaf was planted in high density, about twice as much
CO2 was fixed as was fixed by trees in a tropical rain forest.
Received: April 22, 2002 / Accepted: July 24, 2002
Acknowledgments This project was supported by the Science and Technology Agency (STA) fellowship of the Japan International Science and Technology
Exchange Center (JISTEC), which has been successfully applied by Dr. Shuji Hosoya, Forestry and Forest Products Research Institute.
We thank Dr. Toshio Sumizono and Mr. Masao Sakurai, Forestry and Forest Products Research Institute, for their kind help in
determining the rate of photosynthesis and cultivating the kenaf plants, respectively. We also express our appreciation to
Dr. Quang Hung Le, College of Agriculture and Forestry, Ho Chi Minh City, Vietnam for offering information about the cultivation
of kenaf at Thu Duc District, Ho Chi Minh City. 相似文献