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
Objective To investigate the inhibitory effects of recombinant human bone morphogenetic protein 2 (rhBMP-2) on the proliferation of human glioma cells (SHG44) in vivo and in vitro, and analyze its mechanism. Methds: H...Objective To investigate the inhibitory effects of recombinant human bone morphogenetic protein 2 (rhBMP-2) on the proliferation of human glioma cells (SHG44) in vivo and in vitro, and analyze its mechanism. Methds: Human SHG44 glioma cells were cultured in vitro. The growth curve of SHG44 cells with or without rhBMP-2 was ploted. The pro- liferative action of rhBMP-2 on SHG44 cells was determined by MTT method The cell cycle, ultrastructure and DNA frag-ments of SHG44 cells were detected by now cytometry (FCM), electron microscopy and agarose gel electrophoresis agarose respectively. The growth state of SHG44 glioma under the skin of nude mice was observed with the local injection of rhBMP-2. Results:rhBMP-2 could inhibit the growh of SHG44 cells in vitro. The DNA content of SHG44 cells increased in G1 phase, and decreased in S phase obviously (p<0.01) .An apoptosis spike (12.3%) was demonstrated by FCM as- say. The nucleus chromatin condensation, margination,breakage and apoptosis cells were observed under the electron mi- croscopy.The DNA electrophoresis showed a ladder band (DNA ladder). SHG44 glioma growth in mice was relatively slow-~ er and its volume was smaller with local injection of rhBMP-2 than. those without rhBMP-2 injection (P < 0.01). Conclu-sion: SHG44 cells could be arrested at G1/S phase and the cell growht could be significantly suppressed by rhBMP-2. The process might be carried out thsough rhBMP-2-induced apoptosis in human glioma cells.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Objective To investigate the inhibitory effects of recombinant human bone morphogenetic protein 2 (rhBMP-2) on the proliferation of human glioma cells (SHG44) in vivo and in vitro, and analyze its mechanism. Methds: Human SHG44 glioma cells were cultured in vitro. The growth curve of SHG44 cells with or without rhBMP-2 was ploted. The pro- liferative action of rhBMP-2 on SHG44 cells was determined by MTT method The cell cycle, ultrastructure and DNA frag-ments of SHG44 cells were detected by now cytometry (FCM), electron microscopy and agarose gel electrophoresis agarose respectively. The growth state of SHG44 glioma under the skin of nude mice was observed with the local injection of rhBMP-2. Results:rhBMP-2 could inhibit the growh of SHG44 cells in vitro. The DNA content of SHG44 cells increased in G1 phase, and decreased in S phase obviously (p<0.01) .An apoptosis spike (12.3%) was demonstrated by FCM as- say. The nucleus chromatin condensation, margination,breakage and apoptosis cells were observed under the electron mi- croscopy.The DNA electrophoresis showed a ladder band (DNA ladder). SHG44 glioma growth in mice was relatively slow-~ er and its volume was smaller with local injection of rhBMP-2 than. those without rhBMP-2 injection (P < 0.01). Conclu-sion: SHG44 cells could be arrested at G1/S phase and the cell growht could be significantly suppressed by rhBMP-2. The process might be carried out thsough rhBMP-2-induced apoptosis in human glioma cells.
