AIM To study the expression of proapoptotic gene Bax in human gastric carcinoma and its significance. METHODS Using immunohistochemistry methods, the Bax protein expression in 57 specimens of gastric carcinoma and ...AIM To study the expression of proapoptotic gene Bax in human gastric carcinoma and its significance. METHODS Using immunohistochemistry methods, the Bax protein expression in 57 specimens of gastric carcinoma and its relationship with clinical status and pathomorphological parameters were observed. RESULTS Thirty three (57 89%) cases were positive for Bax protein staining which was mainly located in the cytoplasm of tumor cells. The rate of Bax protein expression was not correlated with the tumor size, lymph node metastasis, depth of invasion, clinical stages of tumors and age and sex of patients ( P >0 05), but strongly associated with the morphological type and differentiation degree of tumors. It was significantly higher in intestinal type and well/moderately differentiated gastric carcinoma than in diffuse type and poorly differentiated gastric carcinoma ( P <0 05 and P <0 01). CONCLUSION The proapoptotic gene Bax is differentially expressed in most of gastric carcinoma and may take part in the modulation of apoptosis in gastric carcinoma. The expression of Bax might be associated with the occurrence of intestinal type gastric carcinoma and the differentiation of gastric carcinoma.展开更多
BACKGROUND: Many studies have showed that apoptosis of endothelial cells plays a curial role in the progress of sepsis. But the role of simvastatin in apoptosis of endothelial cells induced by sepsis is not clear. The...BACKGROUND: Many studies have showed that apoptosis of endothelial cells plays a curial role in the progress of sepsis. But the role of simvastatin in apoptosis of endothelial cells induced by sepsis is not clear. The present study aimed to investigate the role of simvastatin in apoptosis of endothelial cells induced by sepsis and its mechanism.METHODS: Human umbilical vein endothelial cells(HUVECs) were randomly divided into three groups: control group, sepsis serum intervention group(sepsis group) and simvastatin+sepsis serum intervention group(simvastatin group). After 24-hour incubation with corresponding culture medium, the relative growth rate of HUVECS in different groups was detected by MTT assay; the apoptosis of HUVECs was detected by Hoechst33258 assay and fl ow cytometry; and the expression of the Bcl-2 and Bax genes of HUVECs was detected by PCR.RESULTS: Compared with the sepsis group, HUVECs in the simvastatin group had a higher relative growth rate. Apoptotic HUVECs decreased significantly in the simvastatin group in comparison with the sepsis group. Expression of the Bcl-2 gene in HUVECs decreased obviously, but the expression of the Bax gene increased obviously after 24-hour incubation with sepsis serum; however, the expression of the Bcl-2 and Bax genes was just the opposite in the simvastatin group.CONCLUSIONS: Our study suggests that simvastatin can inhibit apoptosis of endothelial cells induced by sepsis through upregulating the expression of Bcl-2 and downregulating Bax. It may be one of the mechanisms for simvastatin to treat sepsis.展开更多
To investigate the role of bax in a vincristine (VCR) induced multidrug resistant (MDR) human gastric cancer cell line, SGC7901/VCR, in which the Bax protein expression level was significantly lower compared with th...To investigate the role of bax in a vincristine (VCR) induced multidrug resistant (MDR) human gastric cancer cell line, SGC7901/VCR, in which the Bax protein expression level was significantly lower compared with that in parent cells Methods A bax eukaryotic expression vector was constructed and transfected into SGC7901/VCR cells by lipofectamine, and resistant clones were selected by G418 Western blotting detected Bax expression in transfectants Tetrazolium blue (MTT) assay evaluated the differences in drug sensitivity and cell cycle changes of transfectants were analyzed using flowcytometry (FCM) Results The bax eukaryotic expression vector was constructed and transfected into SGC7901/VCR cells Through G418 selection, resistant clones were obtained Western blotting demonstrated that the expression of Bax protein was markedly increased in bax transduced cells These cells were more sensitive to adriamycin (ADR) and VCR than mock vector transducted cells Moreover, bax transfection enhanced ADR induced apoptosis and VCR induced G 2/M phase arrest of SGC7901/VCR cells Conclusion Bax was involved in the MDR of SGC7901/VCR cells展开更多
objective: To construct a human Bax eukaryotic expression vector and detect its expression in hu man drug resistant gastric cancer cells. Methods: Bax gene was first inserted into polyclonal sites of pBK CMV vector. T...objective: To construct a human Bax eukaryotic expression vector and detect its expression in hu man drug resistant gastric cancer cells. Methods: Bax gene was first inserted into polyclonal sites of pBK CMV vector. Then the recombinant plasmid vector was trans fected into vincristine resistant human gastric cancer cells SGC7901/VCR by lipofectamine. G418 was used to select resistant clones. Lastly, Western blot was used to observe the expression of Bax protein. Results: Recombinant plasmids were successfully con structed. When the plasmids were trans fected into SGC7901/VCR cellsl stable trans fected cell clones were obtained 30 d after G418 selection. The Western blotting demonstrated a significant expression of Bax protein in pBK-Bax cDNA trans fected cells. Conclusion: This construction of Bax gene transfectant will be conducive to a further study of the role of Bax in gastric cancer multi-drug-resistance.展开更多
Objective To investigate the variance of expression of bcl-2 and bax genes in the genesis or gastric carcinoma as well as their relationship. Methods Thirty-five cases of early-stage gastric carcinoma and Twenty-four ...Objective To investigate the variance of expression of bcl-2 and bax genes in the genesis or gastric carcinoma as well as their relationship. Methods Thirty-five cases of early-stage gastric carcinoma and Twenty-four cases ot chronic atrophic gastritis were studied by immunohistochemical method. Results There were no statistical differences of bcl-2 expression levels between gastric carcinoma and atypical hyperplasia or paracancerous intestinal- epithelial metaplasia(IEM) (P>0.05).There were statistical differences of bcl-2 expression between normal epithe- lial tissues (or non-cancerous IEM) and the other three groups(P<0.05), but no statistical difference between the normal epithelial and the non-cancerous IEM group was observed(P>0.05). The expressions or bax protein were found in the normal epithelial and the other groups in varying degrees,but there were no statistical differences be- tween either two of the groups (P>0.05). The bcl-2/bax ratio was higher in early-stage gastric carcinoma,atypical hy- perplasia and paracancerous intestinal-metaplasia than in the non-cancerous intestinal-metaplasia (P<0.05) and nor- mal epithelial tissues(P<0.01). Conclusion The abnormal expression of bcl-2 protein and bax protein,especially the increased bcl-2/bax ratio, probably play an important role in the course of carcinogenesis or gastric carcinoma.展开更多
文摘AIM To study the expression of proapoptotic gene Bax in human gastric carcinoma and its significance. METHODS Using immunohistochemistry methods, the Bax protein expression in 57 specimens of gastric carcinoma and its relationship with clinical status and pathomorphological parameters were observed. RESULTS Thirty three (57 89%) cases were positive for Bax protein staining which was mainly located in the cytoplasm of tumor cells. The rate of Bax protein expression was not correlated with the tumor size, lymph node metastasis, depth of invasion, clinical stages of tumors and age and sex of patients ( P >0 05), but strongly associated with the morphological type and differentiation degree of tumors. It was significantly higher in intestinal type and well/moderately differentiated gastric carcinoma than in diffuse type and poorly differentiated gastric carcinoma ( P <0 05 and P <0 01). CONCLUSION The proapoptotic gene Bax is differentially expressed in most of gastric carcinoma and may take part in the modulation of apoptosis in gastric carcinoma. The expression of Bax might be associated with the occurrence of intestinal type gastric carcinoma and the differentiation of gastric carcinoma.
基金supported by grants from the Medical Research Foundation of Hunan Province(B2013-040)the Science and Technology Development Foundation of Hengyang City(2010kj38)
文摘BACKGROUND: Many studies have showed that apoptosis of endothelial cells plays a curial role in the progress of sepsis. But the role of simvastatin in apoptosis of endothelial cells induced by sepsis is not clear. The present study aimed to investigate the role of simvastatin in apoptosis of endothelial cells induced by sepsis and its mechanism.METHODS: Human umbilical vein endothelial cells(HUVECs) were randomly divided into three groups: control group, sepsis serum intervention group(sepsis group) and simvastatin+sepsis serum intervention group(simvastatin group). After 24-hour incubation with corresponding culture medium, the relative growth rate of HUVECS in different groups was detected by MTT assay; the apoptosis of HUVECs was detected by Hoechst33258 assay and fl ow cytometry; and the expression of the Bcl-2 and Bax genes of HUVECs was detected by PCR.RESULTS: Compared with the sepsis group, HUVECs in the simvastatin group had a higher relative growth rate. Apoptotic HUVECs decreased significantly in the simvastatin group in comparison with the sepsis group. Expression of the Bcl-2 gene in HUVECs decreased obviously, but the expression of the Bax gene increased obviously after 24-hour incubation with sepsis serum; however, the expression of the Bcl-2 and Bax genes was just the opposite in the simvastatin group.CONCLUSIONS: Our study suggests that simvastatin can inhibit apoptosis of endothelial cells induced by sepsis through upregulating the expression of Bcl-2 and downregulating Bax. It may be one of the mechanisms for simvastatin to treat sepsis.
文摘To investigate the role of bax in a vincristine (VCR) induced multidrug resistant (MDR) human gastric cancer cell line, SGC7901/VCR, in which the Bax protein expression level was significantly lower compared with that in parent cells Methods A bax eukaryotic expression vector was constructed and transfected into SGC7901/VCR cells by lipofectamine, and resistant clones were selected by G418 Western blotting detected Bax expression in transfectants Tetrazolium blue (MTT) assay evaluated the differences in drug sensitivity and cell cycle changes of transfectants were analyzed using flowcytometry (FCM) Results The bax eukaryotic expression vector was constructed and transfected into SGC7901/VCR cells Through G418 selection, resistant clones were obtained Western blotting demonstrated that the expression of Bax protein was markedly increased in bax transduced cells These cells were more sensitive to adriamycin (ADR) and VCR than mock vector transducted cells Moreover, bax transfection enhanced ADR induced apoptosis and VCR induced G 2/M phase arrest of SGC7901/VCR cells Conclusion Bax was involved in the MDR of SGC7901/VCR cells
文摘objective: To construct a human Bax eukaryotic expression vector and detect its expression in hu man drug resistant gastric cancer cells. Methods: Bax gene was first inserted into polyclonal sites of pBK CMV vector. Then the recombinant plasmid vector was trans fected into vincristine resistant human gastric cancer cells SGC7901/VCR by lipofectamine. G418 was used to select resistant clones. Lastly, Western blot was used to observe the expression of Bax protein. Results: Recombinant plasmids were successfully con structed. When the plasmids were trans fected into SGC7901/VCR cellsl stable trans fected cell clones were obtained 30 d after G418 selection. The Western blotting demonstrated a significant expression of Bax protein in pBK-Bax cDNA trans fected cells. Conclusion: This construction of Bax gene transfectant will be conducive to a further study of the role of Bax in gastric cancer multi-drug-resistance.
文摘Objective To investigate the variance of expression of bcl-2 and bax genes in the genesis or gastric carcinoma as well as their relationship. Methods Thirty-five cases of early-stage gastric carcinoma and Twenty-four cases ot chronic atrophic gastritis were studied by immunohistochemical method. Results There were no statistical differences of bcl-2 expression levels between gastric carcinoma and atypical hyperplasia or paracancerous intestinal- epithelial metaplasia(IEM) (P>0.05).There were statistical differences of bcl-2 expression between normal epithe- lial tissues (or non-cancerous IEM) and the other three groups(P<0.05), but no statistical difference between the normal epithelial and the non-cancerous IEM group was observed(P>0.05). The expressions or bax protein were found in the normal epithelial and the other groups in varying degrees,but there were no statistical differences be- tween either two of the groups (P>0.05). The bcl-2/bax ratio was higher in early-stage gastric carcinoma,atypical hy- perplasia and paracancerous intestinal-metaplasia than in the non-cancerous intestinal-metaplasia (P<0.05) and nor- mal epithelial tissues(P<0.01). Conclusion The abnormal expression of bcl-2 protein and bax protein,especially the increased bcl-2/bax ratio, probably play an important role in the course of carcinogenesis or gastric carcinoma.
