INTRODUCTIONHepatocellular carcinoma(HCC)is one of the mostcommon malignancies in China.To date,surgery is stillthe best solution to it.However,metastatic recurrencesafter curative hepatic resections are very common.T...INTRODUCTIONHepatocellular carcinoma(HCC)is one of the mostcommon malignancies in China.To date,surgery is stillthe best solution to it.However,metastatic recurrencesafter curative hepatic resections are very common.Tang etal have reported that recurrence rate within 5 years展开更多
AIM To test the hypothesis to block VEGFexpression of SMMC-7721 hepatoma cells mayinhibit tumor growth using the rat hepatomamodel.METHODS Amplifiy the 200 VEGF cDNAfragment and insert it into human U6 genecassette in...AIM To test the hypothesis to block VEGFexpression of SMMC-7721 hepatoma cells mayinhibit tumor growth using the rat hepatomamodel.METHODS Amplifiy the 200 VEGF cDNAfragment and insert it into human U6 genecassette in the reverse orientation transcribingsmall antisense RNA which could specificallyinteract with VEGF165, and VEGF121 mRNA.Construct the retroviral vector containing thisantisense VEGF U6 cassette and package thereplication-deficient recombinant retrovirus.SMMC-7721 cells were transduced with thesevirus and positive clones were selected withG418. PCR and Southern blot analysis wereperformed to determine if U6 cassette integratedinto the genomic DNA of positive clone.Transfected tumor cells were evaluated for RNAexpression by ribonuclease protection assays.The VEGF protein in the supernatant of parentaltumor cells and genetically modified tumor cellswas determined with ELISA. In vitro and in vivogrowth properties of antisense VEGF cell clonein nude mice were analyzed.RESULTS Restriction enzyme digestion andPCR sequencing verified that the antisense VEGFRNA retroviral vector was successfullyconstructed. After G418 selection, resistantSMMC-7721 cell clone was picked up. PCR andSouthern blot analysis suggested that U6cassette was integrated into the cell genomicDNA. Stable SMMC-7721 cell clone transducedwith U6 antisense RNA cassette could express200bp small antisense VEGF RNA and secretereduced levels of VEGF in culture condition.Production of VEGF by antisense transgeneexpressing cells was 65 ± 10 ng / L per 106 cells,420 ± 45 ng/L per 106 cells in sense group and 485± 30 ng/L per 106 cells in the negative control group, (P＜0.05). The antisense-VEGF cell clone appeared phenotypically indistinguishable from SMMC-7721 cells and SMMC-7721 cells transfected sense VEGF. The growth rate of the antisense-VEGF cell clone was the same as the control cells. When S. C. was implanted into nude mice, growth of antisense-VEGF cell lines was greatly inhibited compared with control cells.CONCLUSION Expression of antisense VEGFRNA in SMMC-7721 cells could decrease thetumorigenicity, and antisense-VEGF genetherapy may be an adjuvant treatment forhepatoma.展开更多
AIM To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesisof human gastric carcinoma more directly.METHODS The expression of VEGF and its receptor kinase-domain insert containing recepto...AIM To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesisof human gastric carcinoma more directly.METHODS The expression of VEGF and its receptor kinase-domain insert containing receptor (KDR) in human gastric cancer tissue were observed by immunohistochemical staining. VEGF levels were manipulated in human gastric cancer cell using eukaryotic expression constructs designed to express the complete VEGF165 complimentary DNA in either the sense or antisense orientation. The biological changes of the cells were observed in which VEGF was up-regulated or downregulated.RESULTS VEGF-positive rate was 50%, and VEGF was mainly localized in the cytoplasm and membrane of the tumor cells, while KDR was mainly located in the membrane of vascular endothelial cells in gastric cancer tissues and peri-cancerous tissue. In 2 cases of 50 specimens, the gastric cancer cells expressed KDR,localized in both the cytoplasm and membrane.Introduction of VEGF165 antisense into human gastric cancer cells ( SGC-7901, immunofluorescence intensity,31.6%)) resulted in a significant reduction in VEGFspecific messenger RNA and total and cell surface VEGF protein ( immunofluorescence intensity, 8.9%)(P＜0.05). Conversely, stable integration of VEGF165 in the sense orientation resulted in an increase in cellular and cell surface VEGF (immunofluorescence intensity,75.4%) (P＜0.05). Lowered VEGF levels were associated with a marked decrease in the growth of nude mouse xenografted tumor (at 33 days postimplantation, tomor volume: 345.40 ± 136.31 mm3) (P＜0.05 vs control SGC7901 group: 1534.40 ± 362.88 mm3), whereas up-regulation of VEGF resulted in increased xenografted tumor size (at 33 days postimplantation, tomor volume: 2350.50 ± 637.70mm3) (P＜0.05 vs control SGC-7901 group).CONCLUSION This study provides direct evidence that VEGF plays an important role in the oncogenesis of human gastric cancer.展开更多
目的:探讨血管新生(angiogenesis)及调控因子与睾酮刺激大鼠良性前列腺增生(BPH)的关系.方法:16只8周龄200～250 g SD大鼠随机分为对照组与模型组各8只,采用去势后皮下注射丙酸睾酮法建立大鼠BPH模型.应用免疫组化结合图像分析系统检测...目的:探讨血管新生(angiogenesis)及调控因子与睾酮刺激大鼠良性前列腺增生(BPH)的关系.方法:16只8周龄200～250 g SD大鼠随机分为对照组与模型组各8只,采用去势后皮下注射丙酸睾酮法建立大鼠BPH模型.应用免疫组化结合图像分析系统检测对照组、BPH模型组前列腺组织微血管密度(MVD)、血管内皮生长因子(VEGF)、血管内皮生长因子受体1(flk-1)、内皮抑素(endostatin)、基质金属蛋白酶2(MMP-2)及其抑制剂(TIMP-2)的表达,并使用逐步引入剔除模型进行多元回归分析.结果:BPH模型组前列腺组织MVD明显增高(P＜0.01),VEGF、flk-1、MMP-2的表达及MMP-2/TIMP-2、VEGF/endostatin比值均高于对照组(P＜0.01),endostatin阳性表达低于对照组(P＜0.01),TIMP-2表达与对照组比较差异无显著性.回归分析显示,MVD与VEGF、VEGF/endostatin、MMP-2/TIMP-2呈明显正相关(r=0.974、0.986、0.982,P均＜0.05),与endostatin呈明显负相关(r=-0.975,P＜0.05).结论:雄激素致大鼠BPH与前列腺组织MVD增加有关,其MVD增加与血管基膜降解后血管内皮细胞增殖有关.展开更多
基金the Shanghai Leading Medical Subjects Grant(№983001)State Key Basic Research Grant(№G1998051211)for financial supports.
文摘INTRODUCTIONHepatocellular carcinoma(HCC)is one of the mostcommon malignancies in China.To date,surgery is stillthe best solution to it.However,metastatic recurrencesafter curative hepatic resections are very common.Tang etal have reported that recurrence rate within 5 years
基金Project supported by National Natural Science Foundation of China,No.863 Z2001-04
文摘AIM To test the hypothesis to block VEGFexpression of SMMC-7721 hepatoma cells mayinhibit tumor growth using the rat hepatomamodel.METHODS Amplifiy the 200 VEGF cDNAfragment and insert it into human U6 genecassette in the reverse orientation transcribingsmall antisense RNA which could specificallyinteract with VEGF165, and VEGF121 mRNA.Construct the retroviral vector containing thisantisense VEGF U6 cassette and package thereplication-deficient recombinant retrovirus.SMMC-7721 cells were transduced with thesevirus and positive clones were selected withG418. PCR and Southern blot analysis wereperformed to determine if U6 cassette integratedinto the genomic DNA of positive clone.Transfected tumor cells were evaluated for RNAexpression by ribonuclease protection assays.The VEGF protein in the supernatant of parentaltumor cells and genetically modified tumor cellswas determined with ELISA. In vitro and in vivogrowth properties of antisense VEGF cell clonein nude mice were analyzed.RESULTS Restriction enzyme digestion andPCR sequencing verified that the antisense VEGFRNA retroviral vector was successfullyconstructed. After G418 selection, resistantSMMC-7721 cell clone was picked up. PCR andSouthern blot analysis suggested that U6cassette was integrated into the cell genomicDNA. Stable SMMC-7721 cell clone transducedwith U6 antisense RNA cassette could express200bp small antisense VEGF RNA and secretereduced levels of VEGF in culture condition.Production of VEGF by antisense transgeneexpressing cells was 65 ± 10 ng / L per 106 cells,420 ± 45 ng/L per 106 cells in sense group and 485± 30 ng/L per 106 cells in the negative control group, (P＜0.05). The antisense-VEGF cell clone appeared phenotypically indistinguishable from SMMC-7721 cells and SMMC-7721 cells transfected sense VEGF. The growth rate of the antisense-VEGF cell clone was the same as the control cells. When S. C. was implanted into nude mice, growth of antisense-VEGF cell lines was greatly inhibited compared with control cells.CONCLUSION Expression of antisense VEGFRNA in SMMC-7721 cells could decrease thetumorigenicity, and antisense-VEGF genetherapy may be an adjuvant treatment forhepatoma.
文摘AIM To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesisof human gastric carcinoma more directly.METHODS The expression of VEGF and its receptor kinase-domain insert containing receptor (KDR) in human gastric cancer tissue were observed by immunohistochemical staining. VEGF levels were manipulated in human gastric cancer cell using eukaryotic expression constructs designed to express the complete VEGF165 complimentary DNA in either the sense or antisense orientation. The biological changes of the cells were observed in which VEGF was up-regulated or downregulated.RESULTS VEGF-positive rate was 50%, and VEGF was mainly localized in the cytoplasm and membrane of the tumor cells, while KDR was mainly located in the membrane of vascular endothelial cells in gastric cancer tissues and peri-cancerous tissue. In 2 cases of 50 specimens, the gastric cancer cells expressed KDR,localized in both the cytoplasm and membrane.Introduction of VEGF165 antisense into human gastric cancer cells ( SGC-7901, immunofluorescence intensity,31.6%)) resulted in a significant reduction in VEGFspecific messenger RNA and total and cell surface VEGF protein ( immunofluorescence intensity, 8.9%)(P＜0.05). Conversely, stable integration of VEGF165 in the sense orientation resulted in an increase in cellular and cell surface VEGF (immunofluorescence intensity,75.4%) (P＜0.05). Lowered VEGF levels were associated with a marked decrease in the growth of nude mouse xenografted tumor (at 33 days postimplantation, tomor volume: 345.40 ± 136.31 mm3) (P＜0.05 vs control SGC7901 group: 1534.40 ± 362.88 mm3), whereas up-regulation of VEGF resulted in increased xenografted tumor size (at 33 days postimplantation, tomor volume: 2350.50 ± 637.70mm3) (P＜0.05 vs control SGC-7901 group).CONCLUSION This study provides direct evidence that VEGF plays an important role in the oncogenesis of human gastric cancer.
文摘目的:探讨血管新生(angiogenesis)及调控因子与睾酮刺激大鼠良性前列腺增生(BPH)的关系.方法:16只8周龄200～250 g SD大鼠随机分为对照组与模型组各8只,采用去势后皮下注射丙酸睾酮法建立大鼠BPH模型.应用免疫组化结合图像分析系统检测对照组、BPH模型组前列腺组织微血管密度(MVD)、血管内皮生长因子(VEGF)、血管内皮生长因子受体1(flk-1)、内皮抑素(endostatin)、基质金属蛋白酶2(MMP-2)及其抑制剂(TIMP-2)的表达,并使用逐步引入剔除模型进行多元回归分析.结果:BPH模型组前列腺组织MVD明显增高(P＜0.01),VEGF、flk-1、MMP-2的表达及MMP-2/TIMP-2、VEGF/endostatin比值均高于对照组(P＜0.01),endostatin阳性表达低于对照组(P＜0.01),TIMP-2表达与对照组比较差异无显著性.回归分析显示,MVD与VEGF、VEGF/endostatin、MMP-2/TIMP-2呈明显正相关(r=0.974、0.986、0.982,P均＜0.05),与endostatin呈明显负相关(r=-0.975,P＜0.05).结论:雄激素致大鼠BPH与前列腺组织MVD增加有关,其MVD增加与血管基膜降解后血管内皮细胞增殖有关.
