AIM: To evaluate the possibility of generation 4 polyamidoamine (G4PAMAM) dendrimers acting as the delivery system of vascular endothelial growth factor (VEGF) antisense oligodeoxynucleotides (VEGFASODN), and to inves...AIM: To evaluate the possibility of generation 4 polyamidoamine (G4PAMAM) dendrimers acting as the delivery system of vascular endothelial growth factor (VEGF) antisense oligodeoxynucleotides (VEGFASODN), and to investigate the anti-tumor effect of G4PAMAM/VEGFASODN complex on the cultured cells and the mouse tumor xenograft model. METHODS: The transfection efficiency was assessed by Row cytometry (FCM). Thiazolyl tetrazolium (MU) assay was performed to determine the relative growth rate (RGR) of the cells after transfection. Then a mouse tumor xenograft model of human retinoblastoma was established. Different interventions were given to the mice by intratumoral injection and the tumor growth was monitored. The expression of VEGF mRNA was detected by reverse transcription PCR (RT-PCR), the expression of VEGF protein was determined by western blot analysis, and the microvessel density (MVD) was measured by immunohistochemistry (IHC) staining. RESULTS: G4PAMAM/VEGFASODN exhibited a high transfection rate in vitro, and the transfection rates of different doses of G4PAMAM/VEGFASODN groups increased with higher doses. This effect was accompanied by a dose-depended reduction in cell viability. The tumor growth in the tumor-bearing athymic mice was significantly inhibited in the G4PAMAM/VEGFASODN group. The expressions of VEGF mRNA and protein were obviously inhibited in the G4PAMAM/VEGFASODN group (p<0.05), and the MVD of the G4PAMAM/VEGFASODN group was lower than that of the other groups(p<0.05). CONCLUSION: VEGFASODN can be delivered into the cultured and transplanted retinoblastoma cells efficiently by G4PAMAM, suppress the expressions of VEGF mRNA and protein, and reduce the MVD of tumor tissues. The G4PAMAM/VEGFASODN complex has antitumor properties vitro and in vivo.展开更多
An amphotropic pseudotype retrovirus containing human N-ras antisense gene was constructed and packaged with helper cells. It has been previously demonstrated that the virus did inhibit the growth of human hepatocarci...An amphotropic pseudotype retrovirus containing human N-ras antisense gene was constructed and packaged with helper cells. It has been previously demonstrated that the virus did inhibit the growth of human hepatocarcinoma cell line PLC PRF/5 in vitro accompanied with the blockage of p21 expression. Based on these results, further study was carried on to examine the effect of these viruses on the growth of human hepatoma transplanted LTNM4 in nude mice. It has been shown that the retrovirus containing human antisense N-ras gene could inhibit the hepatoma in nude mice at a rate of 78% (P<0.05) as compared with saline control. No inhibition was observed in group treated with retrovirus which contained no N-ras sequence. These results in vivo lend further support that human N-ras antisense gene mediated by retrovirus could block the expression of the relevant oncogene and lead to the inhibition of cancer growth. It also provided the basis for further approaches of gene therapy for human cancer.展开更多
文摘AIM: To evaluate the possibility of generation 4 polyamidoamine (G4PAMAM) dendrimers acting as the delivery system of vascular endothelial growth factor (VEGF) antisense oligodeoxynucleotides (VEGFASODN), and to investigate the anti-tumor effect of G4PAMAM/VEGFASODN complex on the cultured cells and the mouse tumor xenograft model. METHODS: The transfection efficiency was assessed by Row cytometry (FCM). Thiazolyl tetrazolium (MU) assay was performed to determine the relative growth rate (RGR) of the cells after transfection. Then a mouse tumor xenograft model of human retinoblastoma was established. Different interventions were given to the mice by intratumoral injection and the tumor growth was monitored. The expression of VEGF mRNA was detected by reverse transcription PCR (RT-PCR), the expression of VEGF protein was determined by western blot analysis, and the microvessel density (MVD) was measured by immunohistochemistry (IHC) staining. RESULTS: G4PAMAM/VEGFASODN exhibited a high transfection rate in vitro, and the transfection rates of different doses of G4PAMAM/VEGFASODN groups increased with higher doses. This effect was accompanied by a dose-depended reduction in cell viability. The tumor growth in the tumor-bearing athymic mice was significantly inhibited in the G4PAMAM/VEGFASODN group. The expressions of VEGF mRNA and protein were obviously inhibited in the G4PAMAM/VEGFASODN group (p<0.05), and the MVD of the G4PAMAM/VEGFASODN group was lower than that of the other groups(p<0.05). CONCLUSION: VEGFASODN can be delivered into the cultured and transplanted retinoblastoma cells efficiently by G4PAMAM, suppress the expressions of VEGF mRNA and protein, and reduce the MVD of tumor tissues. The G4PAMAM/VEGFASODN complex has antitumor properties vitro and in vivo.
文摘An amphotropic pseudotype retrovirus containing human N-ras antisense gene was constructed and packaged with helper cells. It has been previously demonstrated that the virus did inhibit the growth of human hepatocarcinoma cell line PLC PRF/5 in vitro accompanied with the blockage of p21 expression. Based on these results, further study was carried on to examine the effect of these viruses on the growth of human hepatoma transplanted LTNM4 in nude mice. It has been shown that the retrovirus containing human antisense N-ras gene could inhibit the hepatoma in nude mice at a rate of 78% (P<0.05) as compared with saline control. No inhibition was observed in group treated with retrovirus which contained no N-ras sequence. These results in vivo lend further support that human N-ras antisense gene mediated by retrovirus could block the expression of the relevant oncogene and lead to the inhibition of cancer growth. It also provided the basis for further approaches of gene therapy for human cancer.
