AIM: To characterize the CagA variable region of Helicobacter pylori isolates from Chinese patients.METHODS: DNA fragments in CagA variable region were amplified and sequenced respectively from genomic DNA of 19 isola...AIM: To characterize the CagA variable region of Helicobacter pylori isolates from Chinese patients.METHODS: DNA fragments in CagA variable region were amplified and sequenced respectively from genomic DNA of 19 isolates from patients with gastric cancer and 20isolates from patients with chronic gastritis. The tendency of phosphorylation in tyrosine(s) of CagA proteins was evaluated subsequently by phosphorylation assay in vivo and in vitro respectively.RESULTS: About 97.44% (38/39) H pylori isolates possessed CagA gene. CagA+ strains contained 2-4tandem five-amino-acid motifs EPIYA but only one EPIYA had repeated sequence in CagA variable region in different isolates. There was no significant difference between the number of EPIYA motifs in H pylori from patients with different diseases. However, only tyrosine site in EPIYA within repeated sequence could be phosphorylated by AGS cells in vivo although all tyrosine sites in EPIYA could be phosphorylated in vitro.CONCLUSION: CagA in Chinese has no functional difference in perturbing cellular signal pathway among different H pylori isolates.展开更多
AIM:To investigate the clinical significance of the expression of VEGF165mRNA and the correlation with vascular endothelial growth factor(VEGF) protein and inducible nitric oxide synthase (iNO) in human gastric cancer...AIM:To investigate the clinical significance of the expression of VEGF165mRNA and the correlation with vascular endothelial growth factor(VEGF) protein and inducible nitric oxide synthase (iNO) in human gastric cancer.METHODS:We tested VEGF165mRNA expression in 31 cases of resected gastric cancer specimens and normal paired gastric mucosae by RT-PCR.Total RNA was extracted with TRIzol reagents,transcribed into cDNA with gligo (dT15) priming,inner controlled with β-actin expression and agarose gel isolated after PCR.VEGF expression was quantitated with IS1000 imaging system.Meanwhile we also examined expression levels of VEGF protein and iNOS in 85 cases of gastric cancer.All paraffin-embedded samples were immunohistochimically stained by streptavidin-peroxidase method (SP).RESULTS:The mean expression of VEGF165mRNA in gastric cancer was 1.125±0.356,significantly higher than that of normal paired mucosea,which was 0.760±0.278.The data indicated that the expression level of VEGF165mRNA was well related to lymph node metastasis and TNM stages of UICC.The expression levels in patients with lymph node metastasis and without lhmph node metastasis were 1.219±0.377 and 0.927±0.205 respectively (p<0.05),The expression in stages Ⅰ,Ⅱ,Ⅲ,Ⅳ was 0.934±0.194,1.262±0.386 respectively (p<0.01).Further analysis showed the lymph node metastasis rate in the group with over-expression of VEGF was higher than that in the group with low expression of VEGF(83.3% vs 46.2%),and the ratio of stage Ⅲ+Ⅳ in the group with over-expression of VEGF was also higher than that in the group with low expression with VEGF (77.8% vs 33.8%)(p<0.05).The positive rates of expression of VEGF protein and iNOS in 85 cases of gastric cancer were 75.4% and 58.8% respectively,and 50.1% of the patients showed positive staining both for iNOS and VEGF,the correlation with the two tactors was significant (p=0.018).But more intensive analysis showed the immunoreactive grades of VEGF were not associated with that of iNOS.CONCLUSIONS:The expression o展开更多
基金Supported by the National High Technology ResearchDevelopment Program of China, No. 2001AA227111
文摘AIM: To characterize the CagA variable region of Helicobacter pylori isolates from Chinese patients.METHODS: DNA fragments in CagA variable region were amplified and sequenced respectively from genomic DNA of 19 isolates from patients with gastric cancer and 20isolates from patients with chronic gastritis. The tendency of phosphorylation in tyrosine(s) of CagA proteins was evaluated subsequently by phosphorylation assay in vivo and in vitro respectively.RESULTS: About 97.44% (38/39) H pylori isolates possessed CagA gene. CagA+ strains contained 2-4tandem five-amino-acid motifs EPIYA but only one EPIYA had repeated sequence in CagA variable region in different isolates. There was no significant difference between the number of EPIYA motifs in H pylori from patients with different diseases. However, only tyrosine site in EPIYA within repeated sequence could be phosphorylated by AGS cells in vivo although all tyrosine sites in EPIYA could be phosphorylated in vitro.CONCLUSION: CagA in Chinese has no functional difference in perturbing cellular signal pathway among different H pylori isolates.
基金Supported by Science and'Technology Fund of Medicine and Health of Zhejiang Province,No.2000A 116
文摘AIM:To investigate the clinical significance of the expression of VEGF165mRNA and the correlation with vascular endothelial growth factor(VEGF) protein and inducible nitric oxide synthase (iNO) in human gastric cancer.METHODS:We tested VEGF165mRNA expression in 31 cases of resected gastric cancer specimens and normal paired gastric mucosae by RT-PCR.Total RNA was extracted with TRIzol reagents,transcribed into cDNA with gligo (dT15) priming,inner controlled with β-actin expression and agarose gel isolated after PCR.VEGF expression was quantitated with IS1000 imaging system.Meanwhile we also examined expression levels of VEGF protein and iNOS in 85 cases of gastric cancer.All paraffin-embedded samples were immunohistochimically stained by streptavidin-peroxidase method (SP).RESULTS:The mean expression of VEGF165mRNA in gastric cancer was 1.125±0.356,significantly higher than that of normal paired mucosea,which was 0.760±0.278.The data indicated that the expression level of VEGF165mRNA was well related to lymph node metastasis and TNM stages of UICC.The expression levels in patients with lymph node metastasis and without lhmph node metastasis were 1.219±0.377 and 0.927±0.205 respectively (p<0.05),The expression in stages Ⅰ,Ⅱ,Ⅲ,Ⅳ was 0.934±0.194,1.262±0.386 respectively (p<0.01).Further analysis showed the lymph node metastasis rate in the group with over-expression of VEGF was higher than that in the group with low expression of VEGF(83.3% vs 46.2%),and the ratio of stage Ⅲ+Ⅳ in the group with over-expression of VEGF was also higher than that in the group with low expression with VEGF (77.8% vs 33.8%)(p<0.05).The positive rates of expression of VEGF protein and iNOS in 85 cases of gastric cancer were 75.4% and 58.8% respectively,and 50.1% of the patients showed positive staining both for iNOS and VEGF,the correlation with the two tactors was significant (p=0.018).But more intensive analysis showed the immunoreactive grades of VEGF were not associated with that of iNOS.CONCLUSIONS:The expression o
