Objective To investigate the impact of all-trans retinoic acid （ATRA） on MDM2 gene expression in astrocytoma cell line SHG-44, and to provide basic data for further research on the progression mechanism and gene the...Objective To investigate the impact of all-trans retinoic acid （ATRA） on MDM2 gene expression in astrocytoma cell line SHG-44, and to provide basic data for further research on the progression mechanism and gene therapy of human astrocytoma. Methods The differential expressions of MDM2 gene and protein in SHG-44 cells were detected by cDNA microarray and Western blot, respectively, before and after treatment of ATRA. The expressions of MDM2 protein in WHO grade Ⅱ and grade Ⅳ astrocytomas were determined by immunohistochemical streptavidin-peroxidase method. Some differentially expressed genes were selected randomly for Northern blot analysis. Results The intensity ratio of ATRA-treated to untreated SHG-44 cell was 0.37 in the cDNA microarray, suggesting that the expression of MDM2 gene was down-regulated in SHG-44 cells after treatment with ATRA. Some genes differentially expressed in the microarray were confirmed by Northern blot. Western blot demonstrated that the optical density ratios of MDM2 to β-actin in ATRA-treated and untreated SHG-44 were 14.02±0.35 and 21.40±0.58 （t = 24.728, P = 0.000）, respectively, suggesting that the expression of MDM2 protein was inhibited in ATRA-treated SHG-44 cells. Moreover, the percentages of MDM2-positive protein were 24.00% （6/25） and 56.52% （13/23） （x^2 = 5.298, P = 0.021） in WHO grade Ⅱ and grade Ⅳ astrocytomas, respectively, suggesting that the expression of MDM2 protein may increase along with the elevation of astrocytoma malignancy. Conclusion ATRA can inhibit MDM2 gene expression in SHG-44 cells, and MDM2 is related to astrocytoma progression.展开更多
Objective:To explore the suppressing effect ofγ-secretase inhibitor DAPT on proliferation of human glioma cell line SHG-44 in vitro and its mechanism.Methods:The SHG-44 cell was treated by DAPT with different concent...Objective:To explore the suppressing effect ofγ-secretase inhibitor DAPT on proliferation of human glioma cell line SHG-44 in vitro and its mechanism.Methods:The SHG-44 cell was treated by DAPT with different concentration.The proliferation of cells was detected by MTT assay;cell cycle and TSC of CD133^+were determined by flow cytometry analysis technique;the key factor in Notch signaling pathway(Notch-1,Delta-1,Hes-1)was measured by reverse transcrip tase-polymerase chain reaction and western blotting.Results:DAPT inhibited the growth and proliferation of SHG-44 cells significantly(P<0.05).And the inhibiting effect on SHG-44 cells produced by DAPT showed a dose-dependent manner.DAPT increased the rate of cells in G_0/G_1 phase of SHG-44 cells,while it decreased the rate of cells in S phase.TSC of CD133^+was significantly reduced after DAPT treated SHC-44 cells.The expression of protein and mRNA of Notch-1,Delta-1 and Hes-1 were gradually downregulated with the increase of DAPT doses.Conclusions:DAPT can downregulate these key factor in Notch signaling pathway,reduce the TSC of CD133+and inhibit the proliferation of SHC-44 cells.展开更多
BACKGROUND： Genetic abnormalities and changes in gene expression have been shown in various grades of glioma. However, the relationship between gene expression patterns and pathways related to malignant transformatio...BACKGROUND： Genetic abnormalities and changes in gene expression have been shown in various grades of glioma. However, the relationship between gene expression patterns and pathways related to malignant transformation of glioma remains poorly understood. OBJECTIVE： To screen differentially expressed genes between normal and all-trans retinoic acid-treated glioma cell line SHG-44 cells with a complementary DNA （cDNA） microarray. DESIGN, TIME AND SETTING： The genomics, in vitro study was performed at the Laboratory of Neurobiology, Third Military Medical University of Chinese PLA, China from January to October 2007. MATERIALS： The glioma cell line SHG-44 was provided by the Third Military Medical University of Chinese PLA. AII-trans retinoic acid was purchased from Sigma, USA. cDNA microarray was purchased from City University of Hong Kong. METHODS： The glioma cell line SHG-44 was treated with 10 μmol/L all-trans retinoic acid for 3 days Differentiation-related genes were determined using cDNA microarray. MAIN OUTCOME MEASURES： Gene expression patterns were compared between normal and all-trans retinoic acid-treated SHG-44 cells. Differentially expressed genes were randomly selected and determined by Northern blot analysis. RESULTS： Northern blot analysis revealed downregulated RPL 13 gene expression and upregulated SOD2 gene expression, which was identical to cDNA microarray results. Five differentially expressed genes （TPI1, BPGM, ALDOA, LDHA, and RRM1） were shown to be involved in cell metabolism, in six metabolic pathways. Four differentially expressed genes （TPI1, BPGM, ALDOA, and LDHA） were associated with carbohydrate metabolism, such as fructose metabolism, pyruvic acid metabolism, pentose phosphate pathway, glycolysis, and gluconeogenesis. One differentially expressed gene （RRM1） was correlated with purine and pyrimidine metabolism. CONCLUSION： Five metabolic genes （TPI1, BPGM, ALDOA, LDHA, and RRM1）, which participate in cell carbohydrate and nucleotide metabolism, were shown to closely correlate with glioma development.展开更多
基金a grant from the Bureau of Health, Sichuan Province, China (No. 050209).
文摘Objective To investigate the impact of all-trans retinoic acid （ATRA） on MDM2 gene expression in astrocytoma cell line SHG-44, and to provide basic data for further research on the progression mechanism and gene therapy of human astrocytoma. Methods The differential expressions of MDM2 gene and protein in SHG-44 cells were detected by cDNA microarray and Western blot, respectively, before and after treatment of ATRA. The expressions of MDM2 protein in WHO grade Ⅱ and grade Ⅳ astrocytomas were determined by immunohistochemical streptavidin-peroxidase method. Some differentially expressed genes were selected randomly for Northern blot analysis. Results The intensity ratio of ATRA-treated to untreated SHG-44 cell was 0.37 in the cDNA microarray, suggesting that the expression of MDM2 gene was down-regulated in SHG-44 cells after treatment with ATRA. Some genes differentially expressed in the microarray were confirmed by Northern blot. Western blot demonstrated that the optical density ratios of MDM2 to β-actin in ATRA-treated and untreated SHG-44 were 14.02±0.35 and 21.40±0.58 （t = 24.728, P = 0.000）, respectively, suggesting that the expression of MDM2 protein was inhibited in ATRA-treated SHG-44 cells. Moreover, the percentages of MDM2-positive protein were 24.00% （6/25） and 56.52% （13/23） （x^2 = 5.298, P = 0.021） in WHO grade Ⅱ and grade Ⅳ astrocytomas, respectively, suggesting that the expression of MDM2 protein may increase along with the elevation of astrocytoma malignancy. Conclusion ATRA can inhibit MDM2 gene expression in SHG-44 cells, and MDM2 is related to astrocytoma progression.
基金supported by Shaanxi Province Health Department Key Funds(sx201227273)
文摘Objective:To explore the suppressing effect ofγ-secretase inhibitor DAPT on proliferation of human glioma cell line SHG-44 in vitro and its mechanism.Methods:The SHG-44 cell was treated by DAPT with different concentration.The proliferation of cells was detected by MTT assay;cell cycle and TSC of CD133^+were determined by flow cytometry analysis technique;the key factor in Notch signaling pathway(Notch-1,Delta-1,Hes-1)was measured by reverse transcrip tase-polymerase chain reaction and western blotting.Results:DAPT inhibited the growth and proliferation of SHG-44 cells significantly(P<0.05).And the inhibiting effect on SHG-44 cells produced by DAPT showed a dose-dependent manner.DAPT increased the rate of cells in G_0/G_1 phase of SHG-44 cells,while it decreased the rate of cells in S phase.TSC of CD133^+was significantly reduced after DAPT treated SHC-44 cells.The expression of protein and mRNA of Notch-1,Delta-1 and Hes-1 were gradually downregulated with the increase of DAPT doses.Conclusions:DAPT can downregulate these key factor in Notch signaling pathway,reduce the TSC of CD133+and inhibit the proliferation of SHC-44 cells.
基金a grant from the Sichuan Provincial Bureau of Health,No. 050209
文摘BACKGROUND： Genetic abnormalities and changes in gene expression have been shown in various grades of glioma. However, the relationship between gene expression patterns and pathways related to malignant transformation of glioma remains poorly understood. OBJECTIVE： To screen differentially expressed genes between normal and all-trans retinoic acid-treated glioma cell line SHG-44 cells with a complementary DNA （cDNA） microarray. DESIGN, TIME AND SETTING： The genomics, in vitro study was performed at the Laboratory of Neurobiology, Third Military Medical University of Chinese PLA, China from January to October 2007. MATERIALS： The glioma cell line SHG-44 was provided by the Third Military Medical University of Chinese PLA. AII-trans retinoic acid was purchased from Sigma, USA. cDNA microarray was purchased from City University of Hong Kong. METHODS： The glioma cell line SHG-44 was treated with 10 μmol/L all-trans retinoic acid for 3 days Differentiation-related genes were determined using cDNA microarray. MAIN OUTCOME MEASURES： Gene expression patterns were compared between normal and all-trans retinoic acid-treated SHG-44 cells. Differentially expressed genes were randomly selected and determined by Northern blot analysis. RESULTS： Northern blot analysis revealed downregulated RPL 13 gene expression and upregulated SOD2 gene expression, which was identical to cDNA microarray results. Five differentially expressed genes （TPI1, BPGM, ALDOA, LDHA, and RRM1） were shown to be involved in cell metabolism, in six metabolic pathways. Four differentially expressed genes （TPI1, BPGM, ALDOA, and LDHA） were associated with carbohydrate metabolism, such as fructose metabolism, pyruvic acid metabolism, pentose phosphate pathway, glycolysis, and gluconeogenesis. One differentially expressed gene （RRM1） was correlated with purine and pyrimidine metabolism. CONCLUSION： Five metabolic genes （TPI1, BPGM, ALDOA, LDHA, and RRM1）, which participate in cell carbohydrate and nucleotide metabolism, were shown to closely correlate with glioma development.
