BACKGROUND: FasL expression was reported to be asso- ciated with hepatic metastasis of colorectal cancer. The aim of this study was to study FasL gene expression in colorectal carcinoma and its influences on biologica...BACKGROUND: FasL expression was reported to be asso- ciated with hepatic metastasis of colorectal cancer. The aim of this study was to study FasL gene expression in colorectal carcinoma and its influences on biological behavior and he- patic metastasis of colorectal carcinoma. METHODS: FasL gene expressions were examined with re- verse transcriptase-polymerase chain reaction (RT-PCR) in the primary focus of colorectal carcinoma, adjacent can- cerous mucosae, and metastasized liver focus from colorec- tal cancer. HR-8348 cells of human rectal cancer cell line were transfected with FasL cDNA. Cell growth suppression rate and response to 5-FU and carboplatin were observed and analyzed with the MTT method. RESULTS: FasL gene expression was detected in the prima- ry focus of colorectal cancer ( n = 58), adjacent cancerous mucosae ( n = 58), and metastasized hepatic tumor tissues (n =28). The positive rate of FasL expression was 24% (14/ 58), 8% (5/58), and 100% (58/58) in the primary focus, adjacent cancerous mucosae and metastasized hepatic tumor tissues respectively. FasL expression rate in the me- tastasized hepatic tumor tissues was higher than that in the primary focus (χ2 = 43.49, P<0. 01) and adjacent cance- rous mucosae (χ2=57.66, P<0.01). In a group of patients with hepatic metastasis, the FasL expression rate in primary focus was higher than that in patients without hepatic me- tastasis (χ2=3.96, P <0.05). In vitro study positive expres- sion of FasL was shown in transfected HR-8348 cells. When 5-FU or carboplatin was added, there was a significant difference in growth suppression rate between FasL positive and controlled cancer cells (t=9.02, t = 11.93, P<0.01). Under the same concentration of chemotherapeutic agents, the survival rate of FasL positive HR-8348 cells was higher than that of controlled cells. CONCLUSIONS: FasL positive cancer cells are powerfullyresistant to chemotherapeutic agents. The expression of the FasL gene in colorectal cancer cells is related to immune evasion to escape from being killed by immune cells, show- ing stronger drug-resistance, and it facilitates hepatic me- tastasis.展开更多
AIM: To study the activation of cytotoxic T lymphocytes (CTLs) against gastric cancer cells induced by FasL/B7-1 (FB-11) gene-modified tumor cells, and to explore whether co-expression of FasL and B7-1 in SGC-7901 tum...AIM: To study the activation of cytotoxic T lymphocytes (CTLs) against gastric cancer cells induced by FasL/B7-1 (FB-11) gene-modified tumor cells, and to explore whether co-expression of FasL and B7-1 in SGC-7901 tumor cells could initiate synergistic antitumor effect. METHODS: FasL and B7-1 genes were transfected into human SGC-7901 gastric cancer cells with adenovirus vectors. The positive clones were selected by G418. FasL and B7-1 genes were detected by flow cytometry and RT-PCR. Abdominal infiltrating lymphocytes and sensitized spleen cells were obtained from mice that were immunized with SGC-7901/FB-11 or wild type SGC-7901 cells intraperitoneally, and cytotoxicity of these CTLs against tumor cells was determined by MTT assay. RESULTS: Flow cytometry and RT-PCR showed that FasL and B7-1 genes were highly expressed. FasL and B7-1 transfected cancer cells had a high apoptosis index. DNA laddering suggested that FasL and B7-1 genes induced gastric cancer cell apoptosis. FasL+/B7-1+SGC-7901 cells (SGC-7901/FB-11) were inoculated subcutaneously in the dorsal skin of C57BL/6 mice and then decreased their tumorigenicity greatly (z = 2.15-46.10, P＜0.01). SGC- 7901/FB-11 cell-sensitized mice obtained protective immune activity against the rechallenge of wild type SGC 7901 cells (z = 2.06-44.30, P＜0.05). The cytotoxicity of CTLs induced by SGC-7901/FB-11 cells against SGC-7901 was significantly higher than that of CTLs activated by wild-type SGC-7901 cells (84.1±2.4% vs30.5±2.3%,P＜0.05).CONCLUSION: FasL and B7-1 genes can effectively promote the activity of CTLs against gastric cancer cells. FasL/B7-1 molecules play an important role in CTL cytotoxicity.展开更多
AIM: To evaluate the possible value of FasL in gastric cancer gene therapy by investigating the effects of FasL expression on human gastric cancer cell line. METHODS: An adenoviral vector encoding the full-length huma...AIM: To evaluate the possible value of FasL in gastric cancer gene therapy by investigating the effects of FasL expression on human gastric cancer cell line. METHODS: An adenoviral vector encoding the full-length human FasL cDNA was constructed and used to infect a human gastric cancer (SGC-7901) cell line. FasL expression was confirmed by X-gal staining, flow cytometric analysis and RT-PCR. The effect of FasL on cell proliferation was determined by clonogenic assay, cytotoxicity was detected by MTT assay, and cell viability was measured by trypan blue exclusion. The therapeutic efficiency of Ad-FasL in vivo was investigated with a xenograft tumor model in nude mice. RESULTS: SGC-7901 cells infected with Ad-FasL showed increased expression of FasL, resulting in significantly decreased cell growth and colony-forming activity when compared with control adenovirus-infected cells. The cytotoxicity of anti-Fas antibody (CH-11) in gastric cancer cells was stronger than that of ActD (91±8 vs60±5,P<0.01), and the cytotoxicity of Ad-FasL was stronger than that of CH-11 (60±5 vs50±2, P<0.05). In addition, G1-phase arrest (67.75±0.39 vs 58.03±2.16, P<0.05) and apoptosis were observed in Ad-FasL-infected SGC-7901 cells, and the growth of SGC-7901 xenografts in nude mice was retarded after intra-tumoral injection with Ad-FasL (54% vs 0%,P<0.0001). CONCLUSION: Infection of human gastric carcinoma cells with Ad-FasL induces apoptosis, indicating that this target gene might be of potential value in gene therapy for gastric cancer.展开更多
OBJECTIVE: To investigate the effect of FasL gene transfer to islet cells on pancreatic islet allografts. METHODS: A recombinant and replication-deficient type-5 adenovirus encoding murine FasL (AdV- FasL) was constru...OBJECTIVE: To investigate the effect of FasL gene transfer to islet cells on pancreatic islet allografts. METHODS: A recombinant and replication-deficient type-5 adenovirus encoding murine FasL (AdV- FasL) was constructed by the method of calcium phosphate precipitation. Pancreatic islets were infected with the recombinant adenovirus AdV-FasL, and transplanted into diabetic recipients. FasL expression was detected by RT-PCR and immunohistochemistry. The survival of allografts and the apoptosis of gene transferred islet allografts were analyzed. RESULTS: All animals receiving islet allograft alone returned to a diabetic state by several days (mean survival time 6.3±0.6 days). Compared with the control group, no delayed rejection and prolonged survival of allografts were observed in the group of FasL gene transfer. The rejection was accelerated and the allograft survival was shortened to 3.4±0.2 days (P<0.05). Pancreatic islets infected with AdV- FasL demonstrated positive staining of FasL at 24 h, with an increased intensity at 48 h, but not in AdV-5 infected or uninfected islets. TUNEL labeling of pancreatic islet allografts at 24, 48 h revealed apoptosis that was not in AdV-5 infected allografts. CONCLUSIONS: Though co-transplantation of FasL-expressing testicular cells can induce privilege of islet allografts and prolong allograft survival, direct expression of FasL on islet allografts infected with AdV-FasL may accelerate islets rejection by islet apoptosis and granulocyte infiltration.展开更多
基金This study was supported by grants from the " Fifteenth" Military MedicalKey Projects of China (01Z006) and the National Natural Science Founda-tion of China (30271279 and 30070747 ).
文摘BACKGROUND: FasL expression was reported to be asso- ciated with hepatic metastasis of colorectal cancer. The aim of this study was to study FasL gene expression in colorectal carcinoma and its influences on biological behavior and he- patic metastasis of colorectal carcinoma. METHODS: FasL gene expressions were examined with re- verse transcriptase-polymerase chain reaction (RT-PCR) in the primary focus of colorectal carcinoma, adjacent can- cerous mucosae, and metastasized liver focus from colorec- tal cancer. HR-8348 cells of human rectal cancer cell line were transfected with FasL cDNA. Cell growth suppression rate and response to 5-FU and carboplatin were observed and analyzed with the MTT method. RESULTS: FasL gene expression was detected in the prima- ry focus of colorectal cancer ( n = 58), adjacent cancerous mucosae ( n = 58), and metastasized hepatic tumor tissues (n =28). The positive rate of FasL expression was 24% (14/ 58), 8% (5/58), and 100% (58/58) in the primary focus, adjacent cancerous mucosae and metastasized hepatic tumor tissues respectively. FasL expression rate in the me- tastasized hepatic tumor tissues was higher than that in the primary focus (χ2 = 43.49, P<0. 01) and adjacent cance- rous mucosae (χ2=57.66, P<0.01). In a group of patients with hepatic metastasis, the FasL expression rate in primary focus was higher than that in patients without hepatic me- tastasis (χ2=3.96, P <0.05). In vitro study positive expres- sion of FasL was shown in transfected HR-8348 cells. When 5-FU or carboplatin was added, there was a significant difference in growth suppression rate between FasL positive and controlled cancer cells (t=9.02, t = 11.93, P<0.01). Under the same concentration of chemotherapeutic agents, the survival rate of FasL positive HR-8348 cells was higher than that of controlled cells. CONCLUSIONS: FasL positive cancer cells are powerfullyresistant to chemotherapeutic agents. The expression of the FasL gene in colorectal cancer cells is related to immune evasion to escape from being killed by immune cells, show- ing stronger drug-resistance, and it facilitates hepatic me- tastasis.
基金Supported by the Medical Scientific Foundation of Jiangsu Province, No. H200147
文摘AIM: To study the activation of cytotoxic T lymphocytes (CTLs) against gastric cancer cells induced by FasL/B7-1 (FB-11) gene-modified tumor cells, and to explore whether co-expression of FasL and B7-1 in SGC-7901 tumor cells could initiate synergistic antitumor effect. METHODS: FasL and B7-1 genes were transfected into human SGC-7901 gastric cancer cells with adenovirus vectors. The positive clones were selected by G418. FasL and B7-1 genes were detected by flow cytometry and RT-PCR. Abdominal infiltrating lymphocytes and sensitized spleen cells were obtained from mice that were immunized with SGC-7901/FB-11 or wild type SGC-7901 cells intraperitoneally, and cytotoxicity of these CTLs against tumor cells was determined by MTT assay. RESULTS: Flow cytometry and RT-PCR showed that FasL and B7-1 genes were highly expressed. FasL and B7-1 transfected cancer cells had a high apoptosis index. DNA laddering suggested that FasL and B7-1 genes induced gastric cancer cell apoptosis. FasL+/B7-1+SGC-7901 cells (SGC-7901/FB-11) were inoculated subcutaneously in the dorsal skin of C57BL/6 mice and then decreased their tumorigenicity greatly (z = 2.15-46.10, P＜0.01). SGC- 7901/FB-11 cell-sensitized mice obtained protective immune activity against the rechallenge of wild type SGC 7901 cells (z = 2.06-44.30, P＜0.05). The cytotoxicity of CTLs induced by SGC-7901/FB-11 cells against SGC-7901 was significantly higher than that of CTLs activated by wild-type SGC-7901 cells (84.1±2.4% vs30.5±2.3%,P＜0.05).CONCLUSION: FasL and B7-1 genes can effectively promote the activity of CTLs against gastric cancer cells. FasL/B7-1 molecules play an important role in CTL cytotoxicity.
基金Supported by the Medical Scientific Foundation of Jiangsu Province, No. H200147
文摘AIM: To evaluate the possible value of FasL in gastric cancer gene therapy by investigating the effects of FasL expression on human gastric cancer cell line. METHODS: An adenoviral vector encoding the full-length human FasL cDNA was constructed and used to infect a human gastric cancer (SGC-7901) cell line. FasL expression was confirmed by X-gal staining, flow cytometric analysis and RT-PCR. The effect of FasL on cell proliferation was determined by clonogenic assay, cytotoxicity was detected by MTT assay, and cell viability was measured by trypan blue exclusion. The therapeutic efficiency of Ad-FasL in vivo was investigated with a xenograft tumor model in nude mice. RESULTS: SGC-7901 cells infected with Ad-FasL showed increased expression of FasL, resulting in significantly decreased cell growth and colony-forming activity when compared with control adenovirus-infected cells. The cytotoxicity of anti-Fas antibody (CH-11) in gastric cancer cells was stronger than that of ActD (91±8 vs60±5,P<0.01), and the cytotoxicity of Ad-FasL was stronger than that of CH-11 (60±5 vs50±2, P<0.05). In addition, G1-phase arrest (67.75±0.39 vs 58.03±2.16, P<0.05) and apoptosis were observed in Ad-FasL-infected SGC-7901 cells, and the growth of SGC-7901 xenografts in nude mice was retarded after intra-tumoral injection with Ad-FasL (54% vs 0%,P<0.0001). CONCLUSION: Infection of human gastric carcinoma cells with Ad-FasL induces apoptosis, indicating that this target gene might be of potential value in gene therapy for gastric cancer.
基金This study was supported by the National Natural Science Fundation of China (No. 39770726).
文摘OBJECTIVE: To investigate the effect of FasL gene transfer to islet cells on pancreatic islet allografts. METHODS: A recombinant and replication-deficient type-5 adenovirus encoding murine FasL (AdV- FasL) was constructed by the method of calcium phosphate precipitation. Pancreatic islets were infected with the recombinant adenovirus AdV-FasL, and transplanted into diabetic recipients. FasL expression was detected by RT-PCR and immunohistochemistry. The survival of allografts and the apoptosis of gene transferred islet allografts were analyzed. RESULTS: All animals receiving islet allograft alone returned to a diabetic state by several days (mean survival time 6.3±0.6 days). Compared with the control group, no delayed rejection and prolonged survival of allografts were observed in the group of FasL gene transfer. The rejection was accelerated and the allograft survival was shortened to 3.4±0.2 days (P<0.05). Pancreatic islets infected with AdV- FasL demonstrated positive staining of FasL at 24 h, with an increased intensity at 48 h, but not in AdV-5 infected or uninfected islets. TUNEL labeling of pancreatic islet allografts at 24, 48 h revealed apoptosis that was not in AdV-5 infected allografts. CONCLUSIONS: Though co-transplantation of FasL-expressing testicular cells can induce privilege of islet allografts and prolong allograft survival, direct expression of FasL on islet allografts infected with AdV-FasL may accelerate islets rejection by islet apoptosis and granulocyte infiltration.
