The tripeptide,Arg-Gly-Asp（RGD）motif is an integrin-recognition site found in adhesive proteins present in extracellular matrices（ECM）and in the blood.HCT-8 cells were treated with cellular adhesion tripeptide RGD...The tripeptide,Arg-Gly-Asp（RGD）motif is an integrin-recognition site found in adhesive proteins present in extracellular matrices（ECM）and in the blood.HCT-8 cells were treated with cellular adhesion tripeptide RGD at various concentrations.MTT assay was performed to examine the growth and proliferation of HCT-8 cells after treatment with RGD for 48 h.Haematoxylin and Eosin（HE）staining and electromicroscope were used to observe the morphology of apoptotic cells.Survivin and flow cytometry were also used to analyze the HCT-8 apoptosis.Cellular adhesion tripeptide RGD significantly inhibits the growth and proliferation of HCT-8 cells in a dose-dependent manner and induces apoptosis of HCT-8.These results indicate that cellular adhesion tripeptide RGD inhibits the growth and proli-feration of tumor HCT-8 cell,probably by the aid of inducing apoptosis of HCT-8 cell.展开更多
The cell adhesive motif RGD tripeptide was synthesized by using a novel chemical method. First, Gly-Asp（GD） was synthesized in two steps including the chloroacetylation of free L-aspartic acid and the ammonolysis of...The cell adhesive motif RGD tripeptide was synthesized by using a novel chemical method. First, Gly-Asp（GD） was synthesized in two steps including the chloroacetylation of free L-aspartic acid and the ammonolysis of the chloroacetylated L-aspartic acid. The yield of chloroacetylated L-aspartic acid was 83.0%. For the ammonolysis of chloroacetylated L-aspartic acid, the yield of the ammonolyzed product was 92. 3%. Second, the coupling between Arg and Gly-Asp was carried out by using the NCA method. The maximum yield of RGD was about 50% at 0℃ and pH = 9. 5. The prepared RGD tripeptide was confirmed by using amino acid component analysis and mass spectrographic analysis.展开更多
Chemoenzymatic synthesis of tripeptide Bz-RGD-（OEt）2 was conducted in this study. First, the free dipeptide Gly-Asp was synthesized via a novel chemical method, wherein only L-aspaxtic acid was used and was followed...Chemoenzymatic synthesis of tripeptide Bz-RGD-（OEt）2 was conducted in this study. First, the free dipeptide Gly-Asp was synthesized via a novel chemical method, wherein only L-aspaxtic acid was used and was followed by the esterification of Gly-Asp. The formation of the linkage between the third amino acid Bz-Arg-OEt and Gly-Asp-（OEt）2 was completed by using the enzymatic method in organic media. The effects of several factors such as pH, the water content, triethylamine （TEA）, the molar ratio of the substrates, and the reaction time on the yield of Bz-RGD- （OEt）2 were examined. It was obtained that the optimum conditions for Bz-RGD-（OEt）2 synthesis in an ethanol/ Tris-HC1 buffer system （ volume ratio 93： 7 ） were as follows ： pH = 8.0 ; temperature, 30 ℃ ; reaction time, 7 h. The tripeptide yield was 75.2%.展开更多
基金Supported by the Special Medical Science Fund(No.200505177)from Science & Technology Department of Jilin Province,China
文摘The tripeptide,Arg-Gly-Asp（RGD）motif is an integrin-recognition site found in adhesive proteins present in extracellular matrices（ECM）and in the blood.HCT-8 cells were treated with cellular adhesion tripeptide RGD at various concentrations.MTT assay was performed to examine the growth and proliferation of HCT-8 cells after treatment with RGD for 48 h.Haematoxylin and Eosin（HE）staining and electromicroscope were used to observe the morphology of apoptotic cells.Survivin and flow cytometry were also used to analyze the HCT-8 apoptosis.Cellular adhesion tripeptide RGD significantly inhibits the growth and proliferation of HCT-8 cells in a dose-dependent manner and induces apoptosis of HCT-8.These results indicate that cellular adhesion tripeptide RGD inhibits the growth and proli-feration of tumor HCT-8 cell,probably by the aid of inducing apoptosis of HCT-8 cell.
基金Supported by the Special Research Grant from the State Administration of Traditional Chinese Medicine of China( No.2004ZDZX003).
文摘The cell adhesive motif RGD tripeptide was synthesized by using a novel chemical method. First, Gly-Asp（GD） was synthesized in two steps including the chloroacetylation of free L-aspartic acid and the ammonolysis of the chloroacetylated L-aspartic acid. The yield of chloroacetylated L-aspartic acid was 83.0%. For the ammonolysis of chloroacetylated L-aspartic acid, the yield of the ammonolyzed product was 92. 3%. Second, the coupling between Arg and Gly-Asp was carried out by using the NCA method. The maximum yield of RGD was about 50% at 0℃ and pH = 9. 5. The prepared RGD tripeptide was confirmed by using amino acid component analysis and mass spectrographic analysis.
基金Supported by the Special Research Grant from State Administration of Traditional Chinese Medicine of China ( No.2004ZDZX003).
文摘Chemoenzymatic synthesis of tripeptide Bz-RGD-（OEt）2 was conducted in this study. First, the free dipeptide Gly-Asp was synthesized via a novel chemical method, wherein only L-aspaxtic acid was used and was followed by the esterification of Gly-Asp. The formation of the linkage between the third amino acid Bz-Arg-OEt and Gly-Asp-（OEt）2 was completed by using the enzymatic method in organic media. The effects of several factors such as pH, the water content, triethylamine （TEA）, the molar ratio of the substrates, and the reaction time on the yield of Bz-RGD- （OEt）2 were examined. It was obtained that the optimum conditions for Bz-RGD-（OEt）2 synthesis in an ethanol/ Tris-HC1 buffer system （ volume ratio 93： 7 ） were as follows ： pH = 8.0 ; temperature, 30 ℃ ; reaction time, 7 h. The tripeptide yield was 75.2%.
