AIM: To investigate the potential roles of enhancer of zeste homolog2(EZH2), Bmi-1 and mi R-203 in cell proliferation and invasion in hepatocellular carcinoma(HCC) cell line Hep3 B.METHODS: A total of 73 patients who ...AIM: To investigate the potential roles of enhancer of zeste homolog2(EZH2), Bmi-1 and mi R-203 in cell proliferation and invasion in hepatocellular carcinoma(HCC) cell line Hep3 B.METHODS: A total of 73 patients who underwent surgical resection at Fuzong Clinical Medical College of Fujian Medical University were enrolled in this study. Hep3 B cells were cultivated in RPMI 1640 medium supplemented with 10% fetal bovine serum at 37?℃. Vectors that containing c DNA of the EZH2 gene or mi R-203 targeted sh RNA plasmid were constructed, and then transfected into Hep3 B cells. The m RNA expression of mi R-203, EZH2, and Bmi-1 was analyzed using quantitative real-time polymerase chain reaction analysis, and the protein levels of EZH2 and Bmi-1 were detected by Western blot analysis. Effect of EZH2 or mi R-203 on cell proliferation was observed by methyl thiazolyl tetrazolium assay, and cell apoptosis was assessed using flow cytometry. Besides, effect of EZH2 or mi R-203 on tumor cell invasion was detected using Transwell assay.RESULTS: The m RNA levels of EZH2 and Bmi-1 in HCC tissues and in Hep3 B cells were significantly higher compared with those in normal samples(P < 0.01), while mi R-203 level was significantly lower in HCC tissues(P < 0.01). Hep3 B cells transfected with EZH2-sh RNA or mi R-203-sh RNA showed lower expression levels of EZH2 and Bmi-1(P < 0.05). Compared with controls, Hep3 B cells transfected with EZH2-sh RNA had relative slow cell proliferation, indicating that low expression of EZH2 and Bmi-1 and overexpression of mi R-203 could inhibit Hep3 B cell proliferation(P < 0.05). The average apoptosis rate of Hep3 B cells transfected with EZH2-sh RNA vector was about 18.631%, while that of Hep3 B cells transfected with sh RNA vector was about 5.33%, suggesting that EZH2 was down-regulated by transfecting with EZH2-sh RNA, and the down-regulated EZH2 contributed to the cell apoptosis. Low expression of EZH2 and Bmi-1 and overexpression of mi R-203 could reduce Hep3 B cell invasion(P < 0.05).CONCLUSION: Our study suggests that EZH2 and Bmi-1 are up-regulated while mi R-203 is downregulated in Hep3 B cells. Mi R-203 may contribute to the metastasis and enhance apoptosis of HCC cells by regulating EZH2 and Bmi-1. Our study may provide a theoretical basis for metastasis of HCC and targeted therapy of HCC.展开更多
Aim： To evaluate the antiproliferative activity of contragestazol （DL111-IT） on the human prostate cancer cell line PC3 in vitro and in vivo and to elucidate its potential molecular mechanisms. Methods： The cell k...Aim： To evaluate the antiproliferative activity of contragestazol （DL111-IT） on the human prostate cancer cell line PC3 in vitro and in vivo and to elucidate its potential molecular mechanisms. Methods： The cell killing ability of DL111-IT was measured by the 3-（4,5-dimethylthia-zol,2-yl）-2,5-diphenyltetrazolium bromide （MTT） reagent assay method and the tumor xenograft model. The cell cycle was analyzed by flow cytometry and protein expression, including retinoblastoma （pRb）, cyclin-dependent kinase 4 （CDK4） and cyclin D 1, was detected by Western blotting. Results： DL111-IT exhibited high efficiency on cell growth inhibition of the human androgen-independent prostate cancer cell line PC3. The drug concentration that yielded 50 % cell inhibition （IC50 value） was 9.9 mg/mL. In the PC3 tumor xenograft study, DL111-IT （1.25 mg/kg-20.0 mg/kg） given once a day for 10 days significantly inhibited tumor growth, with the inhibition rate ranging from 21% to 50 %. Flow cytometric analysis indicated that DL111-IT could cause GI arrest in the PC3 cell line, but not apoptosis. DL111-IT enhanced pRb expression and down-regulated CDK4 and cyclin D 1 expression, suggesting that cell cycle regulation might contribute to the anticancer property of DL 111- IT. Conclusion： DL111-1T inhibits the proliferation of human androgen-independent prostate cancer cell line PC3 in vitro and in vivo by a cell cycle regulation pathway.展开更多
Objective:To investigate the effects of miR-25-3p on the occurrence,development and proliferation of tongue squamous cell carcinoma cells.Methods:To establish tongue squamous cell carcinoma cell line Tca8113 that stab...Objective:To investigate the effects of miR-25-3p on the occurrence,development and proliferation of tongue squamous cell carcinoma cells.Methods:To establish tongue squamous cell carcinoma cell line Tca8113 that stably and highly express miR-25-3p using recombinant reiroviral vector-mediated gene transfer method.The proliferation of transfected Tca8113 was detected by thiazolyl blue tetrazolium bromide(MTT)and cell colony formation assays.eyclnD1,p21^(cipt)and p27^(kipt)mRNA expressions in the transfected Tca-8113 were detected by quantitative PCR.cyclinD1,p21^(cipt),p27^(kipt),AKT,p-AKT,FOXOt and p-FOX01 expressions in the transfected Tca8113 were detected by western blot analysis.In addition,miR-25-3p expression in the tongue squamous cell carcinoma cell line and tissue specimen was also detected by quantitative PCR.Results:Quantitative PCR showed that mitt-25-3p expression in the tongue squamous cell carcinoma cell lines and tissue specimen was significantly lower than that in the adjacent tissue.MTT and cell colony formation assays showed that after miR-25-3p overexpression,the proliferation of transfected Tca8113 was obviously attenuated.Western blot analysis and quantitative PCR showed that after miR-25-3p overexpression.p21^(cipt)and p27^(kipt)expressions were upregulated,while cyclinD1,AKT,FOXO1 expressions were downregulated,and AKT and FOXO1 phosphorylation was inactivated in the transfected Tca8113 cells.Conclusions:MiR-25-3p inhibited the proliferation of tongue squamous cell carcinoma cells and regulated cell cycle-related protein expression,playing an important role in the occurrence and development of squamous cell carcinoma of the tongue.展开更多
The cytogenetics of HNE- 1 cell line derived from the biopsy of nasopharyngeal carcinoma of a 27- year- old Chinese male has been investigated by chromosomal banding technique. A karyotypic characterization of subtera...The cytogenetics of HNE- 1 cell line derived from the biopsy of nasopharyngeal carcinoma of a 27- year- old Chinese male has been investigated by chromosomal banding technique. A karyotypic characterization of subteraploid and a modal number of 74 - 77 have been revealed in this cell line. All cells contained a series of non- random chromosomal rearrangements. 18 of them, including 5 isochromosomes. were present in all metaphases and 3 of them in a few one. These findings indicated that the severe DNA damage and increase of gene copies may be occurred in genome of HNE- 1 cells.展开更多
Objective To determine whether transforming growth factor betal (TGF-β1)/Smad signaling pathway mediates p53-dependent apoptosis in hepatoma cell lines.Methods Three human hepatic carcinoma cell lines, HepG2, Huh-7, ...Objective To determine whether transforming growth factor betal (TGF-β1)/Smad signaling pathway mediates p53-dependent apoptosis in hepatoma cell lines.Methods Three human hepatic carcinoma cell lines, HepG2, Huh-7, and Hep3B, were used in this study.TGF-β1-induced apoptosis in hepatic carcinoma cell lines was analyzed using TUNEL assay.For identifying the mechanism of apoptosis induced by TGF-β1, cell lines were transfected with a TGF-β1-inducible luciferase reportor plasmid containing Smad4 binding elements.After transfection, cells were treated with TGF-β1, then assayed for luciferase activity.Results The apoptosis rate of HepG2 cell lines (48.51%± 8.21%) was significantly higher than control ( 12.72%±2.18%, P<0.05).But TGF-β1 was not able to induce apoptosis of Huh-7 and Hep3B cell lines.The relative luciferase activity of TGF-β1-treated HepG2 cell lines (4.38) was significantly higher than control (1.00, P< 0.05).But the relative luciferase activity of TGF-β1-treated Huh-7 and Hep3B cell lines less increased compared with control.Conclusions HepG2 cells seem to be highly susceptible to TGF-β1-induced apoptosis compared with Hep3B and Huh-7 cell lines.Smad4 is a central mediator of TGF-β1 signaling transdution pathway.TGF-β1/Smad signaling pathway might mediate p53-dependent apoptosis in hepatoma cell lines.展开更多
The aim of this study was to evaluate the effects of low concentrations of DEHP and MEHP on steroidogenesis in a murine Leydig tumor cell line （MLTC-1） in vitro. The result of flow cytometry analysis revealed that t...The aim of this study was to evaluate the effects of low concentrations of DEHP and MEHP on steroidogenesis in a murine Leydig tumor cell line （MLTC-1） in vitro. The result of flow cytometry analysis revealed that the proportion of apoptotic cells was significantly increased after the exposure to DEHP. All three genes （P450scc, P450c17, and 38HSD） under study showed an increased expression following exposure to DEHP or MEHP, although some insignificant inhibitory effects appeared in the 10μmol/L treatment group as compared with the controls. It was also found that DEHP or MEHP stimulated INSL3 mRNA and protein especially in the 0.001 μmol/L treatment group. Testosterone secretions were stimulated after the exposure to DEHP or MEHP. Alterations of steroidogenic enzymes and INSL3 in MLTC-1 cells might be involved in the biphasic effects of DEHP/MEHP on androgen production.展开更多
AIM:To analyze the expression profiles of a human gastric-cancer-related gene, GCRG123, in human gastric signet-ring cell carcinoma tissues, and to perform bioinformatics analysis on GCRG123. METHODS:In situ hybridiza...AIM:To analyze the expression profiles of a human gastric-cancer-related gene, GCRG123, in human gastric signet-ring cell carcinoma tissues, and to perform bioinformatics analysis on GCRG123. METHODS:In situ hybridization was used to explore the GCRG123 expression pattern in paraffin-embedded gastric tissues, including 15 cases of signet-ring cell carcinoma, 15 of intestinal-type adenocarcinoma, and 15 of normal gastric mucosa. Northern blotting was used to analyze the differences in GCRG123 expression between stomach signet-ring cell carcinoma and intestinal-type adenocarcinoma tissues. Online software, including BLAST, Multalin and BLAT, were applied for bioinformatics analysis. National Center for Biotechnology Information (NCBI) and the University of California Santa Cruz (UCSC) databases were used for the analyses. RESULTS:The in situ hybridization signal appeared as blue precipitates restricted to the cytoplasm. Ten out of 15 cases of gastric signet ring cell carcinoma, normal gastric mucosal epithelium and pyloric glands showed high GCRG123 expression. Low GCRG123 expression was observed in gastric intestinal-type adenocarcinoma and normal gastric glands. Northern blotting revealed that GCRG123 was up-regulated in signet-ring cell carcinoma tissue but down-regulated in intestinal-type adenocarcinoma tissue. BLAST and Multalin analyses revealed that the GCRG123 sequence had 92% similarity with the ORF2 sequence of human long interspersed nuclear element retrotransposons (LINE-1, L1). BLAT analysis indicated that GCRG123 mapped to all chromosomes. GCRG123 was found to integrate in the intron-17 and-23 of Rb, 5' flanking region of IL-2 and clotting factor Ⅸ genes.CONCLUSION:GCRG123, an active member of the L1 family, was up-regulated in human gastric signet-ring cell carcinoma.展开更多
The inhibitory effect of parvovirus H-1 on the colonyforming ability in vitro of QGY-7703, a cultured human hepatoma cell line, and on the formation and growth of its tumors in nude mice was studied. With higher multi...The inhibitory effect of parvovirus H-1 on the colonyforming ability in vitro of QGY-7703, a cultured human hepatoma cell line, and on the formation and growth of its tumors in nude mice was studied. With higher multiplicity of infection (MOI) of H-1 given, survival of the QGY-7703 cells was found to be decreased. H-1 DNA amplification level at 30 h postinfection(p.i.) was detected to be 7.4 times higher than that at 2 h by dispersed cells assay, while the cells were delayed to enter into S phase.Plaques were formed in the indicator cells (new-born human kidney cell line, NBK) by progeny H-1 virus particles released from the infected QGY-7703 cells by infectious cell center assay. The formation of tumors in nude mice by QGY-7703 cells which were injected s c at 2 h postinfection was observed to be prevented in 2 groups with given MOI 25 and 50. The tumor growth of MOI 10 group occurred at a lower exponential rate than that of control,after a 20 d latent period. It was evident that parvovirus H-1 exhibited a direct inhibitory effect on the formation and growth of human hepatoma cells in vivo as well as in vitro.展开更多
This work was supposed by CMB (No. 96—635) This is one of papers of the special issue on gene therapy research (Chin J Cancer Res Vol. 9 No. 4 December, 1997). Although cervical carcinoma cells may express the hu...This work was supposed by CMB (No. 96—635) This is one of papers of the special issue on gene therapy research (Chin J Cancer Res Vol. 9 No. 4 December, 1997). Although cervical carcinoma cells may express the human papillomavirus protein E6 and E7, they fail to induce an effective specific cytotoxic T lymphocyte response. Recent studies suggest that expression of CD 80 (B7 1) on tumor cells is effective to induce antitumor immune responses. 1,2 In our study, CD 80 gene was transfected into human Hela cell line with a CD 80 expression plasmid (B7 1 +pcDNA 3) by electroporation, then the immunogenecity of the modified Hela cell was tested in TLMC (tumor lymphocyte mixed culture) system. Thymidine lymphocyte proliferation assays showed that the response of human peripheral blood lymphocytes (PBLS) to CD 80 positive Hela cells demonstrated a substantial increase in cell proliferation compared to the response to control cells. Cocultivation of allogeneic PBLs with CD 80 positive tumor cells for three days can induce an increased secretion of IL 2. Our results demonstrate an immunostimulatory effect of CD 80 expression on cervical cancer cells, which provides a basis for the development of a therapeutic tumor vaccine.展开更多
文摘AIM: To investigate the potential roles of enhancer of zeste homolog2(EZH2), Bmi-1 and mi R-203 in cell proliferation and invasion in hepatocellular carcinoma(HCC) cell line Hep3 B.METHODS: A total of 73 patients who underwent surgical resection at Fuzong Clinical Medical College of Fujian Medical University were enrolled in this study. Hep3 B cells were cultivated in RPMI 1640 medium supplemented with 10% fetal bovine serum at 37?℃. Vectors that containing c DNA of the EZH2 gene or mi R-203 targeted sh RNA plasmid were constructed, and then transfected into Hep3 B cells. The m RNA expression of mi R-203, EZH2, and Bmi-1 was analyzed using quantitative real-time polymerase chain reaction analysis, and the protein levels of EZH2 and Bmi-1 were detected by Western blot analysis. Effect of EZH2 or mi R-203 on cell proliferation was observed by methyl thiazolyl tetrazolium assay, and cell apoptosis was assessed using flow cytometry. Besides, effect of EZH2 or mi R-203 on tumor cell invasion was detected using Transwell assay.RESULTS: The m RNA levels of EZH2 and Bmi-1 in HCC tissues and in Hep3 B cells were significantly higher compared with those in normal samples(P < 0.01), while mi R-203 level was significantly lower in HCC tissues(P < 0.01). Hep3 B cells transfected with EZH2-sh RNA or mi R-203-sh RNA showed lower expression levels of EZH2 and Bmi-1(P < 0.05). Compared with controls, Hep3 B cells transfected with EZH2-sh RNA had relative slow cell proliferation, indicating that low expression of EZH2 and Bmi-1 and overexpression of mi R-203 could inhibit Hep3 B cell proliferation(P < 0.05). The average apoptosis rate of Hep3 B cells transfected with EZH2-sh RNA vector was about 18.631%, while that of Hep3 B cells transfected with sh RNA vector was about 5.33%, suggesting that EZH2 was down-regulated by transfecting with EZH2-sh RNA, and the down-regulated EZH2 contributed to the cell apoptosis. Low expression of EZH2 and Bmi-1 and overexpression of mi R-203 could reduce Hep3 B cell invasion(P < 0.05).CONCLUSION: Our study suggests that EZH2 and Bmi-1 are up-regulated while mi R-203 is downregulated in Hep3 B cells. Mi R-203 may contribute to the metastasis and enhance apoptosis of HCC cells by regulating EZH2 and Bmi-1. Our study may provide a theoretical basis for metastasis of HCC and targeted therapy of HCC.
基金This study received financial support from the National Natural Science Foundation of China(No.30000209).
文摘Aim： To evaluate the antiproliferative activity of contragestazol （DL111-IT） on the human prostate cancer cell line PC3 in vitro and in vivo and to elucidate its potential molecular mechanisms. Methods： The cell killing ability of DL111-IT was measured by the 3-（4,5-dimethylthia-zol,2-yl）-2,5-diphenyltetrazolium bromide （MTT） reagent assay method and the tumor xenograft model. The cell cycle was analyzed by flow cytometry and protein expression, including retinoblastoma （pRb）, cyclin-dependent kinase 4 （CDK4） and cyclin D 1, was detected by Western blotting. Results： DL111-IT exhibited high efficiency on cell growth inhibition of the human androgen-independent prostate cancer cell line PC3. The drug concentration that yielded 50 % cell inhibition （IC50 value） was 9.9 mg/mL. In the PC3 tumor xenograft study, DL111-IT （1.25 mg/kg-20.0 mg/kg） given once a day for 10 days significantly inhibited tumor growth, with the inhibition rate ranging from 21% to 50 %. Flow cytometric analysis indicated that DL111-IT could cause GI arrest in the PC3 cell line, but not apoptosis. DL111-IT enhanced pRb expression and down-regulated CDK4 and cyclin D 1 expression, suggesting that cell cycle regulation might contribute to the anticancer property of DL 111- IT. Conclusion： DL111-1T inhibits the proliferation of human androgen-independent prostate cancer cell line PC3 in vitro and in vivo by a cell cycle regulation pathway.
基金Supported by Key Disciplines Group Construetion Project of Pudong Health Bureau of Shanghai(Grant No.PWZxk2010-12)
文摘Objective:To investigate the effects of miR-25-3p on the occurrence,development and proliferation of tongue squamous cell carcinoma cells.Methods:To establish tongue squamous cell carcinoma cell line Tca8113 that stably and highly express miR-25-3p using recombinant reiroviral vector-mediated gene transfer method.The proliferation of transfected Tca8113 was detected by thiazolyl blue tetrazolium bromide(MTT)and cell colony formation assays.eyclnD1,p21^(cipt)and p27^(kipt)mRNA expressions in the transfected Tca-8113 were detected by quantitative PCR.cyclinD1,p21^(cipt),p27^(kipt),AKT,p-AKT,FOXOt and p-FOX01 expressions in the transfected Tca8113 were detected by western blot analysis.In addition,miR-25-3p expression in the tongue squamous cell carcinoma cell line and tissue specimen was also detected by quantitative PCR.Results:Quantitative PCR showed that mitt-25-3p expression in the tongue squamous cell carcinoma cell lines and tissue specimen was significantly lower than that in the adjacent tissue.MTT and cell colony formation assays showed that after miR-25-3p overexpression,the proliferation of transfected Tca8113 was obviously attenuated.Western blot analysis and quantitative PCR showed that after miR-25-3p overexpression.p21^(cipt)and p27^(kipt)expressions were upregulated,while cyclinD1,AKT,FOXO1 expressions were downregulated,and AKT and FOXO1 phosphorylation was inactivated in the transfected Tca8113 cells.Conclusions:MiR-25-3p inhibited the proliferation of tongue squamous cell carcinoma cells and regulated cell cycle-related protein expression,playing an important role in the occurrence and development of squamous cell carcinoma of the tongue.
文摘The cytogenetics of HNE- 1 cell line derived from the biopsy of nasopharyngeal carcinoma of a 27- year- old Chinese male has been investigated by chromosomal banding technique. A karyotypic characterization of subteraploid and a modal number of 74 - 77 have been revealed in this cell line. All cells contained a series of non- random chromosomal rearrangements. 18 of them, including 5 isochromosomes. were present in all metaphases and 3 of them in a few one. These findings indicated that the severe DNA damage and increase of gene copies may be occurred in genome of HNE- 1 cells.
文摘Objective To determine whether transforming growth factor betal (TGF-β1)/Smad signaling pathway mediates p53-dependent apoptosis in hepatoma cell lines.Methods Three human hepatic carcinoma cell lines, HepG2, Huh-7, and Hep3B, were used in this study.TGF-β1-induced apoptosis in hepatic carcinoma cell lines was analyzed using TUNEL assay.For identifying the mechanism of apoptosis induced by TGF-β1, cell lines were transfected with a TGF-β1-inducible luciferase reportor plasmid containing Smad4 binding elements.After transfection, cells were treated with TGF-β1, then assayed for luciferase activity.Results The apoptosis rate of HepG2 cell lines (48.51%± 8.21%) was significantly higher than control ( 12.72%±2.18%, P<0.05).But TGF-β1 was not able to induce apoptosis of Huh-7 and Hep3B cell lines.The relative luciferase activity of TGF-β1-treated HepG2 cell lines (4.38) was significantly higher than control (1.00, P< 0.05).But the relative luciferase activity of TGF-β1-treated Huh-7 and Hep3B cell lines less increased compared with control.Conclusions HepG2 cells seem to be highly susceptible to TGF-β1-induced apoptosis compared with Hep3B and Huh-7 cell lines.Smad4 is a central mediator of TGF-β1 signaling transdution pathway.TGF-β1/Smad signaling pathway might mediate p53-dependent apoptosis in hepatoma cell lines.
基金supported by the National Natural Science Foundation of China(No.81273028)
文摘The aim of this study was to evaluate the effects of low concentrations of DEHP and MEHP on steroidogenesis in a murine Leydig tumor cell line （MLTC-1） in vitro. The result of flow cytometry analysis revealed that the proportion of apoptotic cells was significantly increased after the exposure to DEHP. All three genes （P450scc, P450c17, and 38HSD） under study showed an increased expression following exposure to DEHP or MEHP, although some insignificant inhibitory effects appeared in the 10μmol/L treatment group as compared with the controls. It was also found that DEHP or MEHP stimulated INSL3 mRNA and protein especially in the 0.001 μmol/L treatment group. Testosterone secretions were stimulated after the exposure to DEHP or MEHP. Alterations of steroidogenic enzymes and INSL3 in MLTC-1 cells might be involved in the biphasic effects of DEHP/MEHP on androgen production.
基金the Key Project from the 10th Five-year Plan of Chinese PLA, No. 01Z035International Cooperation Project from the 11th Five-year Plan of Chinese PLA, No. 06H044
文摘AIM:To analyze the expression profiles of a human gastric-cancer-related gene, GCRG123, in human gastric signet-ring cell carcinoma tissues, and to perform bioinformatics analysis on GCRG123. METHODS:In situ hybridization was used to explore the GCRG123 expression pattern in paraffin-embedded gastric tissues, including 15 cases of signet-ring cell carcinoma, 15 of intestinal-type adenocarcinoma, and 15 of normal gastric mucosa. Northern blotting was used to analyze the differences in GCRG123 expression between stomach signet-ring cell carcinoma and intestinal-type adenocarcinoma tissues. Online software, including BLAST, Multalin and BLAT, were applied for bioinformatics analysis. National Center for Biotechnology Information (NCBI) and the University of California Santa Cruz (UCSC) databases were used for the analyses. RESULTS:The in situ hybridization signal appeared as blue precipitates restricted to the cytoplasm. Ten out of 15 cases of gastric signet ring cell carcinoma, normal gastric mucosal epithelium and pyloric glands showed high GCRG123 expression. Low GCRG123 expression was observed in gastric intestinal-type adenocarcinoma and normal gastric glands. Northern blotting revealed that GCRG123 was up-regulated in signet-ring cell carcinoma tissue but down-regulated in intestinal-type adenocarcinoma tissue. BLAST and Multalin analyses revealed that the GCRG123 sequence had 92% similarity with the ORF2 sequence of human long interspersed nuclear element retrotransposons (LINE-1, L1). BLAT analysis indicated that GCRG123 mapped to all chromosomes. GCRG123 was found to integrate in the intron-17 and-23 of Rb, 5' flanking region of IL-2 and clotting factor Ⅸ genes.CONCLUSION:GCRG123, an active member of the L1 family, was up-regulated in human gastric signet-ring cell carcinoma.
文摘The inhibitory effect of parvovirus H-1 on the colonyforming ability in vitro of QGY-7703, a cultured human hepatoma cell line, and on the formation and growth of its tumors in nude mice was studied. With higher multiplicity of infection (MOI) of H-1 given, survival of the QGY-7703 cells was found to be decreased. H-1 DNA amplification level at 30 h postinfection(p.i.) was detected to be 7.4 times higher than that at 2 h by dispersed cells assay, while the cells were delayed to enter into S phase.Plaques were formed in the indicator cells (new-born human kidney cell line, NBK) by progeny H-1 virus particles released from the infected QGY-7703 cells by infectious cell center assay. The formation of tumors in nude mice by QGY-7703 cells which were injected s c at 2 h postinfection was observed to be prevented in 2 groups with given MOI 25 and 50. The tumor growth of MOI 10 group occurred at a lower exponential rate than that of control,after a 20 d latent period. It was evident that parvovirus H-1 exhibited a direct inhibitory effect on the formation and growth of human hepatoma cells in vivo as well as in vitro.
文摘This work was supposed by CMB (No. 96—635) This is one of papers of the special issue on gene therapy research (Chin J Cancer Res Vol. 9 No. 4 December, 1997). Although cervical carcinoma cells may express the human papillomavirus protein E6 and E7, they fail to induce an effective specific cytotoxic T lymphocyte response. Recent studies suggest that expression of CD 80 (B7 1) on tumor cells is effective to induce antitumor immune responses. 1,2 In our study, CD 80 gene was transfected into human Hela cell line with a CD 80 expression plasmid (B7 1 +pcDNA 3) by electroporation, then the immunogenecity of the modified Hela cell was tested in TLMC (tumor lymphocyte mixed culture) system. Thymidine lymphocyte proliferation assays showed that the response of human peripheral blood lymphocytes (PBLS) to CD 80 positive Hela cells demonstrated a substantial increase in cell proliferation compared to the response to control cells. Cocultivation of allogeneic PBLs with CD 80 positive tumor cells for three days can induce an increased secretion of IL 2. Our results demonstrate an immunostimulatory effect of CD 80 expression on cervical cancer cells, which provides a basis for the development of a therapeutic tumor vaccine.
