AIM： To explore the therapeutic efficacy and mechanism of herpes simplex virus-thymidine kinase （HSV-tk） targeting angiogenesis against hepatocellular carcinoma in vivio and in vitro. METHODS： Recombinant adenovir...AIM： To explore the therapeutic efficacy and mechanism of herpes simplex virus-thymidine kinase （HSV-tk） targeting angiogenesis against hepatocellular carcinoma in vivio and in vitro. METHODS： Recombinant adenovirus containing kinase domain insert with receptor （KDR） or cytomegalovirus （CMV） promoter-controlled HSV-tk gene （AdKDR-tk and AdCMV-tk） was constructed using pAdeasy system. The expression of KDR antigen in human umbilical venous endothelial cells （HUVEC） and HepG2 was detected with histological analysis of cells. The virus was used to infect HUVEC and HepG2. Following administration of ganciclovir （GCV）, the survival rate of gene-transfected HUVEC and HepG2 was evaluated by MTT method. To develop hepatocarcinomas in 32 Balb/C mice with HepG2 cells, the mice were divided into four groups： ganciclovir group （Ⅰ）, Ad group （Ⅱ）, AdCMV-tk group （Ⅲ） and AdKDR-tk group （Ⅳ）. Then selective administration of recombinant adenovirus or Ad via the intratumorial was given to all rats. Ganciclovir （GCV） was given at a dose of 100 mg·kg^-1·d^-1 （ip） started on the following day and lasted 10 d. Microvessel density （MVD） of tumor in all the treated animals were examined by the immunohistochemical methods and tumor burden was evaluated 10 d before and alter the last GCV dose.RESULTS： Immunocytochemical staining indicated the expression of KDR antigen in HUVEC. Under adenovirus infection index of 100, with increasing GCV concentration from 0 up to 50 mg/L, the survival rate of AdKDR-tk- transfected HUVEC and HepG2 decreased from 100% to （28.94 ± 5.67）% and （75.45 ± 2.91）% at proper order, respectively （P 〈 0.01）, while the survival rate of AdCMV- tk-transfected HUVEC and HepG2 declined from 100% to （17.56 ± 2.48）% and （23.15± 5.72）%, respectively （P 〉 0.05）. Compared with group I, there was a decrease of tumor weight by 14.7% in group Ⅲ and by 23.6% in group Ⅳ. And there was a distinct difference between group M and Ⅳ （P 〈 0.05）. The median MVD for all groups was 37.4 ± 8.6, 30.6 ± 7.8, 27.6 ± 7.1, and 10.7 ± 4.1 （microvessels/mm^2） in group Ⅰ, Ⅱ, M and IV, respectively. And there was a marked difference between group M and Ⅱ （P 〈 0.05）, Ⅳ and Ⅱ （P 〈 0.01）, and Ⅳ and M （P 〈 0.01）. CONCLUSION： KDR promoter-HSV-tk gene may effectually restrain the growth of tumor via targeting angiogenesis for hepatocellular carcinoma with treatment of GCV.展开更多
The killing effects of herpes simplex virus thymidine kinase gene/ganciclovir （HSV-tk/GCV） approach by the addition of several commonly clinical chemotherapeutic agents on hormone refractory prostate cancer （HRPC）...The killing effects of herpes simplex virus thymidine kinase gene/ganciclovir （HSV-tk/GCV） approach by the addition of several commonly clinical chemotherapeutic agents on hormone refractory prostate cancer （HRPC） cells PC-3m were investigated. After transferring of the HSV-tk gene into PC-3m cells, mRNA and protein expression of HSV-tk was detected by reverse-transcript polymerase chain reaction （RT-PCR） and strept avidin-biotin complex （SABC） im- munohistochemical method. The killing effect of GCV, cisplatin （CDDP）, etoposide （VP-16）, vincristine （VCR）, methotrexate （MTX）, 5-fluorouracil （5-Fu）, and suramin on PC-3m cells was evaluated by morphological assessment analysis, trypan blue exclusion assay and MTT assay respectively. Additionally, the cooperative effect of HSV-tk/GCV system combined with the above agents on the target cancer cells was determined by MTT. Furthermore, apoptosis and necrosis induced by GCV plus 5-Fu or suramin was analyzed by flow cytometry （FCM）. The results showed that that there was HSV-tk mRNA and protein expression in pDR2-tk plasmid transduced PC-3m cell. Combination of GCV with VP-16, VCR, 5-Fu or suramin led to an enhanced cellular killing effect, but with CDDP resulted in a reduced one and with MTX in an approximate one. FCM revealed that synergistic use of GCV and 5-fu or suramin resulted in a rather large proportion of apoptosis and necrosis with the apoptosis index being 36.38 % and 35.51%, and the proportion of necrosis being 33.05 % and 28.87 %, respectively. In conclusion, HSV-tk/CGV approach by addition of certain clinical available chemotherapeutic drugs brings on statistically significant enhanced cell killing over single-agent treatment. Our results highlight the potential for such new combination therapies for future treatments of HRPC.展开更多
Objective: To construct expression vector containing fusion genes of herpes simplex virus thymidine kinase(Hsv-tk), Interleukin-2(IL-2) with internal ribosome entry sites(IRES), and to assess their expression in cell ...Objective: To construct expression vector containing fusion genes of herpes simplex virus thymidine kinase(Hsv-tk), Interleukin-2(IL-2) with internal ribosome entry sites(IRES), and to assess their expression in cell line Tca8113. Methods: IL-2 cDNA was obtained by reverse transcription. Hsv-tk, IL-2 and IRES genes were amplified by PCR. The purified amplification products were inserted into pGEM-T-Easy, and transformed into E.coli JM109. The purified recombinant plasmids were identified by restriction endonucleases. The recombinant plasmids were digested and pEGFP-N 3 were linearized, DNA fragments of Hsv-tk, IRES and IL-2 were ligated into linearized pEGFP-N 3, and then transferred into E.coli JM109. The recombinant tk-IL-2 genes were cloned separately and introduced into the expression vector pEGFP-N 3 containing GFP. The recombinant vectors were identified by their restriction sites through PCR. The plasmids pEGFP-TI was also transfected into Tca8113 cells by calcium phosphate method for the expression of fusion proteins. Fusion genes expressing vector PL(TI)SN was generated by the fusion of HSV-tk, IRES and IL-2 with the use of DNA recombination technology. The recombinant retroviruses were transferred into Tca8113 cells by lipofectamine. The positive clones were obtained after G418 selection and named Tca/TI respectively. Results: The pEGFP-TI pasmid was identified respectively by restriction endonucleases, and their fragment sizes were 1 120 bp and 450 bp. The pEGFP-TI pasmid as templates were amplified respectively by PCR, and their PCR products were 1 120 bp and 450 bp. The pEGFP-TI vectors were used to transfect Tca8113 cell, and the cells with fluorescence accounted for 60% of the total amount. Conclusion: pFGFP-tk-IRES-IL-2 expressing vector is easy to assess the expression of tk-IRES-IL-2-GFP fusion protein localization in transfected cells. The successful construction of expressing vector containing fusion genes of Hsv-tk, IRES and IL-2 may be beneficial for gene therapy in cell line Tca8113.展开更多
基金Supported by the National Natural Science Foundation of China, No. 30371386the Natural Science Foundation of Guangdong Province, No. 31010
文摘AIM： To explore the therapeutic efficacy and mechanism of herpes simplex virus-thymidine kinase （HSV-tk） targeting angiogenesis against hepatocellular carcinoma in vivio and in vitro. METHODS： Recombinant adenovirus containing kinase domain insert with receptor （KDR） or cytomegalovirus （CMV） promoter-controlled HSV-tk gene （AdKDR-tk and AdCMV-tk） was constructed using pAdeasy system. The expression of KDR antigen in human umbilical venous endothelial cells （HUVEC） and HepG2 was detected with histological analysis of cells. The virus was used to infect HUVEC and HepG2. Following administration of ganciclovir （GCV）, the survival rate of gene-transfected HUVEC and HepG2 was evaluated by MTT method. To develop hepatocarcinomas in 32 Balb/C mice with HepG2 cells, the mice were divided into four groups： ganciclovir group （Ⅰ）, Ad group （Ⅱ）, AdCMV-tk group （Ⅲ） and AdKDR-tk group （Ⅳ）. Then selective administration of recombinant adenovirus or Ad via the intratumorial was given to all rats. Ganciclovir （GCV） was given at a dose of 100 mg·kg^-1·d^-1 （ip） started on the following day and lasted 10 d. Microvessel density （MVD） of tumor in all the treated animals were examined by the immunohistochemical methods and tumor burden was evaluated 10 d before and alter the last GCV dose.RESULTS： Immunocytochemical staining indicated the expression of KDR antigen in HUVEC. Under adenovirus infection index of 100, with increasing GCV concentration from 0 up to 50 mg/L, the survival rate of AdKDR-tk- transfected HUVEC and HepG2 decreased from 100% to （28.94 ± 5.67）% and （75.45 ± 2.91）% at proper order, respectively （P 〈 0.01）, while the survival rate of AdCMV- tk-transfected HUVEC and HepG2 declined from 100% to （17.56 ± 2.48）% and （23.15± 5.72）%, respectively （P 〉 0.05）. Compared with group I, there was a decrease of tumor weight by 14.7% in group Ⅲ and by 23.6% in group Ⅳ. And there was a distinct difference between group M and Ⅳ （P 〈 0.05）. The median MVD for all groups was 37.4 ± 8.6, 30.6 ± 7.8, 27.6 ± 7.1, and 10.7 ± 4.1 （microvessels/mm^2） in group Ⅰ, Ⅱ, M and IV, respectively. And there was a marked difference between group M and Ⅱ （P 〈 0.05）, Ⅳ and Ⅱ （P 〈 0.01）, and Ⅳ and M （P 〈 0.01）. CONCLUSION： KDR promoter-HSV-tk gene may effectually restrain the growth of tumor via targeting angiogenesis for hepatocellular carcinoma with treatment of GCV.
文摘The killing effects of herpes simplex virus thymidine kinase gene/ganciclovir （HSV-tk/GCV） approach by the addition of several commonly clinical chemotherapeutic agents on hormone refractory prostate cancer （HRPC） cells PC-3m were investigated. After transferring of the HSV-tk gene into PC-3m cells, mRNA and protein expression of HSV-tk was detected by reverse-transcript polymerase chain reaction （RT-PCR） and strept avidin-biotin complex （SABC） im- munohistochemical method. The killing effect of GCV, cisplatin （CDDP）, etoposide （VP-16）, vincristine （VCR）, methotrexate （MTX）, 5-fluorouracil （5-Fu）, and suramin on PC-3m cells was evaluated by morphological assessment analysis, trypan blue exclusion assay and MTT assay respectively. Additionally, the cooperative effect of HSV-tk/GCV system combined with the above agents on the target cancer cells was determined by MTT. Furthermore, apoptosis and necrosis induced by GCV plus 5-Fu or suramin was analyzed by flow cytometry （FCM）. The results showed that that there was HSV-tk mRNA and protein expression in pDR2-tk plasmid transduced PC-3m cell. Combination of GCV with VP-16, VCR, 5-Fu or suramin led to an enhanced cellular killing effect, but with CDDP resulted in a reduced one and with MTX in an approximate one. FCM revealed that synergistic use of GCV and 5-fu or suramin resulted in a rather large proportion of apoptosis and necrosis with the apoptosis index being 36.38 % and 35.51%, and the proportion of necrosis being 33.05 % and 28.87 %, respectively. In conclusion, HSV-tk/CGV approach by addition of certain clinical available chemotherapeutic drugs brings on statistically significant enhanced cell killing over single-agent treatment. Our results highlight the potential for such new combination therapies for future treatments of HRPC.
文摘Objective: To construct expression vector containing fusion genes of herpes simplex virus thymidine kinase(Hsv-tk), Interleukin-2(IL-2) with internal ribosome entry sites(IRES), and to assess their expression in cell line Tca8113. Methods: IL-2 cDNA was obtained by reverse transcription. Hsv-tk, IL-2 and IRES genes were amplified by PCR. The purified amplification products were inserted into pGEM-T-Easy, and transformed into E.coli JM109. The purified recombinant plasmids were identified by restriction endonucleases. The recombinant plasmids were digested and pEGFP-N 3 were linearized, DNA fragments of Hsv-tk, IRES and IL-2 were ligated into linearized pEGFP-N 3, and then transferred into E.coli JM109. The recombinant tk-IL-2 genes were cloned separately and introduced into the expression vector pEGFP-N 3 containing GFP. The recombinant vectors were identified by their restriction sites through PCR. The plasmids pEGFP-TI was also transfected into Tca8113 cells by calcium phosphate method for the expression of fusion proteins. Fusion genes expressing vector PL(TI)SN was generated by the fusion of HSV-tk, IRES and IL-2 with the use of DNA recombination technology. The recombinant retroviruses were transferred into Tca8113 cells by lipofectamine. The positive clones were obtained after G418 selection and named Tca/TI respectively. Results: The pEGFP-TI pasmid was identified respectively by restriction endonucleases, and their fragment sizes were 1 120 bp and 450 bp. The pEGFP-TI pasmid as templates were amplified respectively by PCR, and their PCR products were 1 120 bp and 450 bp. The pEGFP-TI vectors were used to transfect Tca8113 cell, and the cells with fluorescence accounted for 60% of the total amount. Conclusion: pFGFP-tk-IRES-IL-2 expressing vector is easy to assess the expression of tk-IRES-IL-2-GFP fusion protein localization in transfected cells. The successful construction of expressing vector containing fusion genes of Hsv-tk, IRES and IL-2 may be beneficial for gene therapy in cell line Tca8113.
