Objective: To study the role of SV40 early region gene coding product large tumor antigen(Tag) expression and the interaction between Tag and tumor suppressors p53 and pRb in human brain tumorigenesis. Methods: Tag wa...Objective: To study the role of SV40 early region gene coding product large tumor antigen(Tag) expression and the interaction between Tag and tumor suppressors p53 and pRb in human brain tumorigenesis. Methods: Tag was investigated by immunoprecipitation followed by silver staining and Western blot in 65 cases of human brain tumors and 8 cases of normal brain tissues. Tag-p53 and Tag-pRb complexes were screened by immunoprecipitation and Western blot in 18 and 15 Tag positive tumor tissues respectively. Results: SV40 Tag was expressed generally in human brain tumors, its positive rate was 66. 2% (43 /65). However, Eight normal brain tissues were all negative for Tag, there was significant difference between them(P < 0. 05). Tag-p53 complex was detected in all of 18 Tag positive tumors as well as Tag-pRb complex in all of 15 Tag positive tumors. Conclnsion: SV40 Tag expression is associated with human brain tumorigenesis. The inactivation of p53 and pRh due to the formation of Tag-p53 and Tag-pRb complexes is possibly an important mechanism in the etiopathogenesis of human brain tumors.展开更多
目的建立稳定分化大鼠骨骺软骨细胞株,为细胞替代治疗和基因治疗小儿生长发育迟缓提供稳定的细胞来源。方法利用脂质体介导的基因转染技术将含有猿肾病毒40大T抗原(simian virus 40 large T antigen gene,SV40LTag)基因的质粒pEGFP-IRES...目的建立稳定分化大鼠骨骺软骨细胞株,为细胞替代治疗和基因治疗小儿生长发育迟缓提供稳定的细胞来源。方法利用脂质体介导的基因转染技术将含有猿肾病毒40大T抗原(simian virus 40 large T antigen gene,SV40LTag)基因的质粒pEGFP-IRES2-SV40LTag转染原代培养的新生大鼠骨骺软骨细胞,G418筛选,抗性克隆扩大培养传代。应用II型胶原、X型胶原和SV40LTag抗体进行细胞鉴定,体外检测其分化能力,观察细胞的形态及其生长状况,绘制细胞生长曲线。用RT-PCR、Southern blot和免疫细胞化学法鉴定SV40LTag在转染细胞中的表达。结果转染后获得了阳性细胞克隆,免疫细胞化学证实为具有较强增殖能力和多分化潜能的骨骺软骨细胞。经Southern印迹杂交证实,SV40LTag已稳定转染入骨骺软骨细胞,表达mRNA及其蛋白。结论SV40LTag导入可诱导骨骺软骨细胞稳定分化,为细胞替代治疗和基因治疗小儿生长发育迟缓等疾病提供稳定的细胞来源。展开更多
Objective: To investigate the expression of SV40 Tag and formation of Tag-p53 and Tag-Rb complexes in Chinese brain tumors. Methods: SV40 large tumor antigen (Tag) were investigated by immunoprecipitation, silver stai...Objective: To investigate the expression of SV40 Tag and formation of Tag-p53 and Tag-Rb complexes in Chinese brain tumors. Methods: SV40 large tumor antigen (Tag) were investigated by immunoprecipitation, silver staining and Western blot in 65 cases of Chinese brain tumors and 8 cases of normal brain tissues. Tag-p53 and Tag-Rb complexes were screened by the same way in 20 and 15 Tag positive tumor tissues respectively. Results: Tag was found in all of 8 ependymomas and 2 choroid plexus papillomas, 90% (9/10) of pituitary adenomas, 73% (11/15) of astrocytomas, 70% (7/10) of meningiomas, 50% (4/8) of glioblastoma multiform, 33% (2/6) of medulloblastomas, 5 oligodendrogliomas, 1 pineocytoma and 8 normal brain tissues were negative for Tag. Tag-p53 complex was detected in all of 20 Tag positive tumors as well as Tag-Rb complex in all of 15 Tag positive tumors. Conclusion: SV40 Tag is not only expressed in human brain tumors, but also it can form specific complexes with tumor suppressors p53 and Rb. SV40 is correlated to human brain tumorigenesis. The inactivation of p53 and Rb due to the formation of Tag-p53 and Tag-Rb complexes is possibly an important mechanism in the etiopathogenesis of human brain tumors.展开更多
AIM: To develop a hepatocyte cell line, we immortalized primary porcine hepatocytes with a retroviral vector SSR#69 containing the Simian Virus 40 T antigen (SV40T ag). METHODS: We first established a method of porcin...AIM: To develop a hepatocyte cell line, we immortalized primary porcine hepatocytes with a retroviral vector SSR#69 containing the Simian Virus 40 T antigen (SV40T ag). METHODS: We first established a method of porcine hepatocyte isolation with a modified four-step retrograde perfusion technique. Then the porcine hepatocytes were immortalized with retroviral vector SSR#69 expressing SV40T and hygromycin-resistance genes flanked by paired loxP recombination targets. SV40T cDNA in the expanded cells was subsequently excised by Cre/LoxP site-specific recombination. RESULTS: The resultant hepatocytes with high viability (97%) were successfully immortalized with retroviral vector SSR#69. One of the immortalized clones showed the typical morphological appearance, TJPH-1, and was selected by clone rings and expanded in culture. After excision of the SV40T gene with Cre-recombinase, cells stopped growing. The population of reverted cells exhibited the characteristics of differentiated hepatocytes. CONCLUSION: In conclusion, we herein describe a modified method of hepatocyte isolation and subsequently established a porcine hepatocyte cell line mediated by retroviral transfer and site-specific recombination.展开更多
基金National Natural Science Foundation of China!No.39470724
文摘Objective: To study the role of SV40 early region gene coding product large tumor antigen(Tag) expression and the interaction between Tag and tumor suppressors p53 and pRb in human brain tumorigenesis. Methods: Tag was investigated by immunoprecipitation followed by silver staining and Western blot in 65 cases of human brain tumors and 8 cases of normal brain tissues. Tag-p53 and Tag-pRb complexes were screened by immunoprecipitation and Western blot in 18 and 15 Tag positive tumor tissues respectively. Results: SV40 Tag was expressed generally in human brain tumors, its positive rate was 66. 2% (43 /65). However, Eight normal brain tissues were all negative for Tag, there was significant difference between them(P < 0. 05). Tag-p53 complex was detected in all of 18 Tag positive tumors as well as Tag-pRb complex in all of 15 Tag positive tumors. Conclnsion: SV40 Tag expression is associated with human brain tumorigenesis. The inactivation of p53 and pRh due to the formation of Tag-p53 and Tag-pRb complexes is possibly an important mechanism in the etiopathogenesis of human brain tumors.
文摘目的建立稳定分化大鼠骨骺软骨细胞株,为细胞替代治疗和基因治疗小儿生长发育迟缓提供稳定的细胞来源。方法利用脂质体介导的基因转染技术将含有猿肾病毒40大T抗原(simian virus 40 large T antigen gene,SV40LTag)基因的质粒pEGFP-IRES2-SV40LTag转染原代培养的新生大鼠骨骺软骨细胞,G418筛选,抗性克隆扩大培养传代。应用II型胶原、X型胶原和SV40LTag抗体进行细胞鉴定,体外检测其分化能力,观察细胞的形态及其生长状况,绘制细胞生长曲线。用RT-PCR、Southern blot和免疫细胞化学法鉴定SV40LTag在转染细胞中的表达。结果转染后获得了阳性细胞克隆,免疫细胞化学证实为具有较强增殖能力和多分化潜能的骨骺软骨细胞。经Southern印迹杂交证实,SV40LTag已稳定转染入骨骺软骨细胞,表达mRNA及其蛋白。结论SV40LTag导入可诱导骨骺软骨细胞稳定分化,为细胞替代治疗和基因治疗小儿生长发育迟缓等疾病提供稳定的细胞来源。
基金This work was supported by China Postdoctoral Science Foundation (No. 1998-23).
文摘Objective: To investigate the expression of SV40 Tag and formation of Tag-p53 and Tag-Rb complexes in Chinese brain tumors. Methods: SV40 large tumor antigen (Tag) were investigated by immunoprecipitation, silver staining and Western blot in 65 cases of Chinese brain tumors and 8 cases of normal brain tissues. Tag-p53 and Tag-Rb complexes were screened by the same way in 20 and 15 Tag positive tumor tissues respectively. Results: Tag was found in all of 8 ependymomas and 2 choroid plexus papillomas, 90% (9/10) of pituitary adenomas, 73% (11/15) of astrocytomas, 70% (7/10) of meningiomas, 50% (4/8) of glioblastoma multiform, 33% (2/6) of medulloblastomas, 5 oligodendrogliomas, 1 pineocytoma and 8 normal brain tissues were negative for Tag. Tag-p53 complex was detected in all of 20 Tag positive tumors as well as Tag-Rb complex in all of 15 Tag positive tumors. Conclusion: SV40 Tag is not only expressed in human brain tumors, but also it can form specific complexes with tumor suppressors p53 and Rb. SV40 is correlated to human brain tumorigenesis. The inactivation of p53 and Rb due to the formation of Tag-p53 and Tag-Rb complexes is possibly an important mechanism in the etiopathogenesis of human brain tumors.
基金Supported by The Major Scientific and Technological Project of Hubei Province, No. 2007ABD005
文摘AIM: To develop a hepatocyte cell line, we immortalized primary porcine hepatocytes with a retroviral vector SSR#69 containing the Simian Virus 40 T antigen (SV40T ag). METHODS: We first established a method of porcine hepatocyte isolation with a modified four-step retrograde perfusion technique. Then the porcine hepatocytes were immortalized with retroviral vector SSR#69 expressing SV40T and hygromycin-resistance genes flanked by paired loxP recombination targets. SV40T cDNA in the expanded cells was subsequently excised by Cre/LoxP site-specific recombination. RESULTS: The resultant hepatocytes with high viability (97%) were successfully immortalized with retroviral vector SSR#69. One of the immortalized clones showed the typical morphological appearance, TJPH-1, and was selected by clone rings and expanded in culture. After excision of the SV40T gene with Cre-recombinase, cells stopped growing. The population of reverted cells exhibited the characteristics of differentiated hepatocytes. CONCLUSION: In conclusion, we herein describe a modified method of hepatocyte isolation and subsequently established a porcine hepatocyte cell line mediated by retroviral transfer and site-specific recombination.
