INTRODUCTIONDendritic cells (DCs) play a key regulatory role inantitumor immunity,especially in its immuneaccessory role via MHC-Ⅰ molecules.We haverecently reported that DCs were able to enhance thekilling activity ...INTRODUCTIONDendritic cells (DCs) play a key regulatory role inantitumor immunity,especially in its immuneaccessory role via MHC-Ⅰ molecules.We haverecently reported that DCs were able to enhance thekilling activity of Lymphokine and PHA activatedkiller (LPAK) cells in vitro.In the presentstudy,we evaluated the effects of GM-CSF andTNF upon antitumor activities of freshly展开更多
AIM To establish a cell culture system with long-term replication of hepatitis C virus in vitro.``METHODS Human hepatoma cell line 7721 was tested for its susceptibility to HCV by incubating with a serum from a patien...AIM To establish a cell culture system with long-term replication of hepatitis C virus in vitro.``METHODS Human hepatoma cell line 7721 was tested for its susceptibility to HCV by incubating with a serum from a patient with chronic hepatitis C. Cells and supernatant were harvested at various phases during the culturing periods The presence of HCV RNA, the expression of HCV antigens in cells and/or supernatant were examined by RT-PCR, in situ hybridization and immunohistochemistry respectively.``RESULTS The intracellular HCV RNA was first detected on d 2 after infection and then could be intermittently detected in both cells and supernatant over a period of at least three months. The expression of HCV NS3, CP10antigens could be observed in cells. The fresh cells could be infected by supematant from cultured infected cells and the transmission of viral genome from HCV-infected 7721 cells to PBMCs was also observed.``CONCLUSION The hepatoma line 7721 is not only susceptible to HCV but also supports its long-term replication in vitro.展开更多
INTRODUCTIONTo date ,the major therapy for rectal carcinoma is extensive abdomino-perineal resection[1]. Unfortunately ,after resection of rectal carcinoma ,many patients still die of blood-borne metastases ,usually i...INTRODUCTIONTo date ,the major therapy for rectal carcinoma is extensive abdomino-perineal resection[1]. Unfortunately ,after resection of rectal carcinoma ,many patients still die of blood-borne metastases ,usually in the liver or lungs ,or local prlvic recurrence[2,3],which is the major cause of morbidity and mortality in patients with rectal carcinoma .Pre-or postoperative radiotherapy can reduce the incidence of local rdcurrence[4-7].展开更多
AIM: To clarify the biological role of stem cell factor (SCF)-mediated wild-type KIT receptor activation in gastrointestinal stromal tumor (GIST) growth. METHODS: The co-expression of wild-type KIT receptor and SCF wa...AIM: To clarify the biological role of stem cell factor (SCF)-mediated wild-type KIT receptor activation in gastrointestinal stromal tumor (GIST) growth. METHODS: The co-expression of wild-type KIT receptor and SCF was evaluated in 51 GIST samples using mutation analysis and immunohistochemistry, and the results were correlated with clinicopathological param- eters, including the mitotic count, proliferative index (Ki-67 immunohistochemical staining), mitotic index (phospho-histone H3 immunohistochemical staining) and apoptotic index (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling). Using primary cultured GIST cells, the effect of SCF-mediated wild-type KIT receptor activation was determined by western blotting, methyl thiazolyl tetrazolium (MTT), and apoptosis assays. RESULTS: We found that wild-type KIT receptor and SCF protein were expressed in 100% and 76.5% of the 51 GIST samples, respectively, and the co-expression of wild-type KIT receptor and SCF was associated with known indicators of poor prognosis, including larger tumor size (P = 0.0118), higher mitotic count (P = 0.0058), higher proliferative index (P = 0.0012), higher mitotic index (P = 0.0282), lower apoptosis index (P = 0.0484), and increased National Institutes of Health risk level (P = 0.0012). We also found that the introduction of exogenous SCF potently increased KIT kinase activity, stimulated cell proliferation (P < 0.01) and inhibited apoptosis (P < 0.01) induced by serum starvation, while a KIT immunoblocking antibody suppressed proliferation (P = 0.01) and promoted apoptosis (P < 0.01) in cultured GIST cells. CONCLUSION: SCF-mediated wild-type KIT receptor activation plays an important role in GIST cell growth. The inhibition of SCF-mediated wild-type KIT receptor activation may prove to be particularly important for GIST therapy.展开更多
Compared with 2D tumor cell culture, 3D tumor cell culture can better simulate the microenvironment of signal transduction between cells and extracellular matrix. As one of the best cell models in tumor research, it h...Compared with 2D tumor cell culture, 3D tumor cell culture can better simulate the microenvironment of signal transduction between cells and extracellular matrix. As one of the best cell models in tumor research, it has been widely used in the study of cancer cell morphology, nanotechnology drug delivery system, and anticancer drug screening. The main theme of this paper is to review the previous research of 3D cell culture applying to tumors in vitro and the prospects for the applications of 3D cell culture system.展开更多
Objective: To study the effects of recombinant human Nk4 on the growth and invasion activities of tumor cells. Methods: The inhibition of recombinant human NK4 on human oophoroma, cervical tumor, breast tumor and g...Objective: To study the effects of recombinant human Nk4 on the growth and invasion activities of tumor cells. Methods: The inhibition of recombinant human NK4 on human oophoroma, cervical tumor, breast tumor and gallbladder tumor cells was evaluated in vitro by basement membrane invasion assay. Results: rhNK4 could markedly inhibited the growth of human oophoroma, cervical tumor and breast tumor cells. The inhibition rates of human oophoroma, cervical tumor, breast tumor and gallbladder tumor cells were 48.2%, 29.2%, 58.4% and 30.1% respectively. Conclusion: rhNK4 factor can markedly inhibit the invasion of multiple tumor cells.展开更多
AIM: There are conflicting data about p53 function on cellular sensitivity to the cytotoxic action of 5-fluorouracil (5-FU).Therefore the objective of this study was to determine the combined effects of adenovirus-med...AIM: There are conflicting data about p53 function on cellular sensitivity to the cytotoxic action of 5-fluorouracil (5-FU).Therefore the objective of this study was to determine the combined effects of adenovirus-mediated wild-type (wt) p53 gene transfer and 5-FU chemotherapy on pancreatic cancer cells with different p53 gene status.METHODS: Human pancreatic cancer cell lines Capan-1^p53mut,Capan-2^p53wt, FAMPAC^p53mut, PANG1^p53mut, and rat pancreatic cancer cell lines AS^p53wt and DSL6A^p53null were used for in vitro studies. Following infection with different ratios of Adp53-particles (MOI) in combination with 5-FU, proliferation of tumor cells and apoptosis were quantified by cell proliferation assay (WST-1) and FACS (PI-staining). In addition, DSL6A syngeneic pancreatic tumor cells were inoculated subcutaneously in to Lewis rats for in vivostudies.Tumor size, apoptosis (TUNEL) and survival were determined.RESULTS: Ad-p53 gene transfer combined with 5-FU significantly inhibited tumor cell proliferation and substantially enhanced apoptosis in all four cell lines with an alteration in the p53 gene compared to those two cell lines containing wt-p53. In vivo experiments showed the most effective tumor regression in animals treated with Ad-p53 plus 5-FU. Both in vitroand in vivoanalyses revealed that a sublethal dose of Ad-p53 augmented the apoptotic response induced by 5-FU.CONCLUSION: Our results suggest that Ad-p53 may synergistically enhance 5-FU-chemosensitivity most strikingly in pancreatic cancer cells lacking p53 function. These findings illustrate that the anticancer efficacy of this combination treatment is dependent on the p53 gene status of the target tumor cells.展开更多
INTRODUCTIONDevelopment of drug-resistance to chemotherapyand subsequent metastasis of tumor are primarilyresponsible for treatment failure and the death fromcancer. There have been many previous studies onthe relatio...INTRODUCTIONDevelopment of drug-resistance to chemotherapyand subsequent metastasis of tumor are primarilyresponsible for treatment failure and the death fromcancer. There have been many previous studies onthe relationship between expression of multidrugresistance (MDR) phenotype P-glycoprotein (P-gp)and the malignant properties of tumors, but theresults are often conflicting[1-8]. The difference intumor types or MDR phenotype induced by specificagents might account for this discrepancy. Taxotere(TXT), a member of the family of taxanes, hasantitumor activity through its effect of promotingthe polymerization of tubulin[9,10].展开更多
AIM To evaluate antihepatoma effect ofantisense phosphorothioate oligodeo-xyribonucleotides (S-ODNs) targeted to alpha-fetoprotein (AFP) genes in vitro and in nudemice.METHODS AFP gene expression was examinedby immuno...AIM To evaluate antihepatoma effect ofantisense phosphorothioate oligodeo-xyribonucleotides (S-ODNs) targeted to alpha-fetoprotein (AFP) genes in vitro and in nudemice.METHODS AFP gene expression was examinedby immunocytochemical method or enzyme-linked immunosorbent assay. Effect of S-ODNson SMMC-7721 human hepatoma cell growth invitro was determined using microculturetetrazolium assay. In vivo antitumor activitiesof S-ODNs were monitored by measuring tumorweight differences in treated and control micebearing SMMC-7721 xenografts. Induction of cellapoptosis was evaluated by fluorescence-activated cell sorter (FACS) analysis.RESULTS Antisense S-ODN treatment led toreduced AFP gene expression. Specificantisense S-ODNs, but not control S-ODNs,inhibited the growth of heaptoma cells in vitro.In vivo. only antisense S-ODNs exhibitedobvious antitumor activities. FACS analysisrevealed that the growth inhibition by antisenseS. ODNs was associated with their cell apoptosisinduction.CONCLUSION Antisense S-ODNs targeted toAFP genes inhibit the growth of human hepatomacells and solid hepatoma, which is related totheir cell apoptosis induction.展开更多
Local infiltration and distal dissemination of tumor cells hamper efficacy of current treatments against central nervous system(CNS)tumors and greatly influence mortality and therapy-induced long-term morbidity in sur...Local infiltration and distal dissemination of tumor cells hamper efficacy of current treatments against central nervous system(CNS)tumors and greatly influence mortality and therapy-induced long-term morbidity in survivors.A number of in vitro and ex vivo assay systems have been established to better understand the infiltration and metastatic processes,to search for molecules that specifically block tumor cell infiltration and metastatic dissemination and to pre-clinically evaluate their efficaciousness.These systems allow analytical testing of tumor cell viability and motile and invasive capabilities in simplified and well-controlled environments.However,the urgent need for novel anti-metastatic therapies has provided an incentive for the further development of not only classical in vitro methods but also of novel,physiologically more relevant assay systems including organotypic brain slice culture.In this review,using publicly available peer-reviewed primary research and review articles,we provide an overview of a selection of in vitro and ex vivo techniques widely used to study growth and dissemination of primary metastatic brain tumors.Furthermore,we discuss how our steadily increasing knowledge of tumor biology and the tumor microenvironment could be integrated to improve current research methods for metastatic brain tumors.We believe that such rationally improved methods will ultimately increase our understanding of the biology of brain tumors and facilitate the development of more efficacious anti-metastatic treatments.展开更多
基金Natural Science Foundation of the Higher Education Office of Guangdong Province,No.19952901
文摘INTRODUCTIONDendritic cells (DCs) play a key regulatory role inantitumor immunity,especially in its immuneaccessory role via MHC-Ⅰ molecules.We haverecently reported that DCs were able to enhance thekilling activity of Lymphokine and PHA activatedkiller (LPAK) cells in vitro.In the presentstudy,we evaluated the effects of GM-CSF andTNF upon antitumor activities of freshly
基金Suppprted by the Mational Natural Science Foundation of China,No.39670672.
文摘AIM To establish a cell culture system with long-term replication of hepatitis C virus in vitro.``METHODS Human hepatoma cell line 7721 was tested for its susceptibility to HCV by incubating with a serum from a patient with chronic hepatitis C. Cells and supernatant were harvested at various phases during the culturing periods The presence of HCV RNA, the expression of HCV antigens in cells and/or supernatant were examined by RT-PCR, in situ hybridization and immunohistochemistry respectively.``RESULTS The intracellular HCV RNA was first detected on d 2 after infection and then could be intermittently detected in both cells and supernatant over a period of at least three months. The expression of HCV NS3, CP10antigens could be observed in cells. The fresh cells could be infected by supematant from cultured infected cells and the transmission of viral genome from HCV-infected 7721 cells to PBMCs was also observed.``CONCLUSION The hepatoma line 7721 is not only susceptible to HCV but also supports its long-term replication in vitro.
基金Supported by the National Natural-Scientific Foundation,No.39500043
文摘INTRODUCTIONTo date ,the major therapy for rectal carcinoma is extensive abdomino-perineal resection[1]. Unfortunately ,after resection of rectal carcinoma ,many patients still die of blood-borne metastases ,usually in the liver or lungs ,or local prlvic recurrence[2,3],which is the major cause of morbidity and mortality in patients with rectal carcinoma .Pre-or postoperative radiotherapy can reduce the incidence of local rdcurrence[4-7].
基金Supported by The National Natural Science Foundation of China, No.30700809 and No.30972876
文摘AIM: To clarify the biological role of stem cell factor (SCF)-mediated wild-type KIT receptor activation in gastrointestinal stromal tumor (GIST) growth. METHODS: The co-expression of wild-type KIT receptor and SCF was evaluated in 51 GIST samples using mutation analysis and immunohistochemistry, and the results were correlated with clinicopathological param- eters, including the mitotic count, proliferative index (Ki-67 immunohistochemical staining), mitotic index (phospho-histone H3 immunohistochemical staining) and apoptotic index (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling). Using primary cultured GIST cells, the effect of SCF-mediated wild-type KIT receptor activation was determined by western blotting, methyl thiazolyl tetrazolium (MTT), and apoptosis assays. RESULTS: We found that wild-type KIT receptor and SCF protein were expressed in 100% and 76.5% of the 51 GIST samples, respectively, and the co-expression of wild-type KIT receptor and SCF was associated with known indicators of poor prognosis, including larger tumor size (P = 0.0118), higher mitotic count (P = 0.0058), higher proliferative index (P = 0.0012), higher mitotic index (P = 0.0282), lower apoptosis index (P = 0.0484), and increased National Institutes of Health risk level (P = 0.0012). We also found that the introduction of exogenous SCF potently increased KIT kinase activity, stimulated cell proliferation (P < 0.01) and inhibited apoptosis (P < 0.01) induced by serum starvation, while a KIT immunoblocking antibody suppressed proliferation (P = 0.01) and promoted apoptosis (P < 0.01) in cultured GIST cells. CONCLUSION: SCF-mediated wild-type KIT receptor activation plays an important role in GIST cell growth. The inhibition of SCF-mediated wild-type KIT receptor activation may prove to be particularly important for GIST therapy.
文摘Compared with 2D tumor cell culture, 3D tumor cell culture can better simulate the microenvironment of signal transduction between cells and extracellular matrix. As one of the best cell models in tumor research, it has been widely used in the study of cancer cell morphology, nanotechnology drug delivery system, and anticancer drug screening. The main theme of this paper is to review the previous research of 3D cell culture applying to tumors in vitro and the prospects for the applications of 3D cell culture system.
文摘Objective: To study the effects of recombinant human Nk4 on the growth and invasion activities of tumor cells. Methods: The inhibition of recombinant human NK4 on human oophoroma, cervical tumor, breast tumor and gallbladder tumor cells was evaluated in vitro by basement membrane invasion assay. Results: rhNK4 could markedly inhibited the growth of human oophoroma, cervical tumor and breast tumor cells. The inhibition rates of human oophoroma, cervical tumor, breast tumor and gallbladder tumor cells were 48.2%, 29.2%, 58.4% and 30.1% respectively. Conclusion: rhNK4 factor can markedly inhibit the invasion of multiple tumor cells.
文摘AIM: There are conflicting data about p53 function on cellular sensitivity to the cytotoxic action of 5-fluorouracil (5-FU).Therefore the objective of this study was to determine the combined effects of adenovirus-mediated wild-type (wt) p53 gene transfer and 5-FU chemotherapy on pancreatic cancer cells with different p53 gene status.METHODS: Human pancreatic cancer cell lines Capan-1^p53mut,Capan-2^p53wt, FAMPAC^p53mut, PANG1^p53mut, and rat pancreatic cancer cell lines AS^p53wt and DSL6A^p53null were used for in vitro studies. Following infection with different ratios of Adp53-particles (MOI) in combination with 5-FU, proliferation of tumor cells and apoptosis were quantified by cell proliferation assay (WST-1) and FACS (PI-staining). In addition, DSL6A syngeneic pancreatic tumor cells were inoculated subcutaneously in to Lewis rats for in vivostudies.Tumor size, apoptosis (TUNEL) and survival were determined.RESULTS: Ad-p53 gene transfer combined with 5-FU significantly inhibited tumor cell proliferation and substantially enhanced apoptosis in all four cell lines with an alteration in the p53 gene compared to those two cell lines containing wt-p53. In vivo experiments showed the most effective tumor regression in animals treated with Ad-p53 plus 5-FU. Both in vitroand in vivoanalyses revealed that a sublethal dose of Ad-p53 augmented the apoptotic response induced by 5-FU.CONCLUSION: Our results suggest that Ad-p53 may synergistically enhance 5-FU-chemosensitivity most strikingly in pancreatic cancer cells lacking p53 function. These findings illustrate that the anticancer efficacy of this combination treatment is dependent on the p53 gene status of the target tumor cells.
基金Supported in part by phone-Poulenc Rorer Pharmaceuticals INC
文摘INTRODUCTIONDevelopment of drug-resistance to chemotherapyand subsequent metastasis of tumor are primarilyresponsible for treatment failure and the death fromcancer. There have been many previous studies onthe relationship between expression of multidrugresistance (MDR) phenotype P-glycoprotein (P-gp)and the malignant properties of tumors, but theresults are often conflicting[1-8]. The difference intumor types or MDR phenotype induced by specificagents might account for this discrepancy. Taxotere(TXT), a member of the family of taxanes, hasantitumor activity through its effect of promotingthe polymerization of tubulin[9,10].
基金Supported by the National Postdoctoral Science Foundation of China,No.199711.
文摘AIM To evaluate antihepatoma effect ofantisense phosphorothioate oligodeo-xyribonucleotides (S-ODNs) targeted to alpha-fetoprotein (AFP) genes in vitro and in nudemice.METHODS AFP gene expression was examinedby immunocytochemical method or enzyme-linked immunosorbent assay. Effect of S-ODNson SMMC-7721 human hepatoma cell growth invitro was determined using microculturetetrazolium assay. In vivo antitumor activitiesof S-ODNs were monitored by measuring tumorweight differences in treated and control micebearing SMMC-7721 xenografts. Induction of cellapoptosis was evaluated by fluorescence-activated cell sorter (FACS) analysis.RESULTS Antisense S-ODN treatment led toreduced AFP gene expression. Specificantisense S-ODNs, but not control S-ODNs,inhibited the growth of heaptoma cells in vitro.In vivo. only antisense S-ODNs exhibitedobvious antitumor activities. FACS analysisrevealed that the growth inhibition by antisenseS. ODNs was associated with their cell apoptosisinduction.CONCLUSION Antisense S-ODNs targeted toAFP genes inhibit the growth of human hepatomacells and solid hepatoma, which is related totheir cell apoptosis induction.
文摘Local infiltration and distal dissemination of tumor cells hamper efficacy of current treatments against central nervous system(CNS)tumors and greatly influence mortality and therapy-induced long-term morbidity in survivors.A number of in vitro and ex vivo assay systems have been established to better understand the infiltration and metastatic processes,to search for molecules that specifically block tumor cell infiltration and metastatic dissemination and to pre-clinically evaluate their efficaciousness.These systems allow analytical testing of tumor cell viability and motile and invasive capabilities in simplified and well-controlled environments.However,the urgent need for novel anti-metastatic therapies has provided an incentive for the further development of not only classical in vitro methods but also of novel,physiologically more relevant assay systems including organotypic brain slice culture.In this review,using publicly available peer-reviewed primary research and review articles,we provide an overview of a selection of in vitro and ex vivo techniques widely used to study growth and dissemination of primary metastatic brain tumors.Furthermore,we discuss how our steadily increasing knowledge of tumor biology and the tumor microenvironment could be integrated to improve current research methods for metastatic brain tumors.We believe that such rationally improved methods will ultimately increase our understanding of the biology of brain tumors and facilitate the development of more efficacious anti-metastatic treatments.