AIM: To investigate the effects of 8-Br-cAMP on differentiation and apoptosis of human esophageal cancer cell line Eca-109, and the related gene expression.METHODS: The cultured Eca-109 cells were divided into four gr...AIM: To investigate the effects of 8-Br-cAMP on differentiation and apoptosis of human esophageal cancer cell line Eca-109, and the related gene expression.METHODS: The cultured Eca-109 cells were divided into four groups: E1 group (co-cultured with 8-Br-cAMP for 24 h); E2 group (co-cultured with 8-Br-cAMP for 48 h); C1 group (treated without 8-Br-cAMP for 24 h); and C2 group (treated without 8-Br-cAMP for 48 h). The same concentration of cell suspension of each group was dropped separately onto the slides and nitrocellulose membranes (NCM). The biotin-labeled cDNA probes for c-myc, wild-type (wt) p53, bcl-2 and iNOS were prepared for in situ hybridization. The expressions of epidermal growth factor receptor (EGFR), p38 kinase, FAS, FasL and caspase-3 were detected using immunocytochemistry, and the NOS activity and the ratio of differentiated cells/proliferating cells were examined by cytochemistry. Immunocytochemistry, cytochemistry,and in situ hybridization were separately carried out on both slides and NCM specimens for each group. In addition, TUNEL was used to detect the cell apoptosis rate in each group.RESULTS: The apoptotic rate of E2 group was significantly higher compared to E1 group, while there was no difference in the ratio of differentiated cells/ proliferating cells between E1 and E2 groups. The signals of wt p53 and iNOS were markedly stronger, while the signals of c-myc and EGFR were obviously weaker in E1 group than those in C1 group (P<0.05). Moreover, the signals of wt p53, iNOS, p38 kinase, caspase-3 and NOS activity were significantly stronger, whereas, the signals of bcl-2, c-myc and Fas/FasL were markedly weaker in E2 group than those in C2 group (P<0.05). CONCLUSION: The differentiation and apoptosis of human esophageal cancer cell Eca-109 can be induced after 24- and 48-h treatment with 8-BrcAMP, respectively. Upregulation of wt p53, iNOS and downregulation of c-myc may be associated with differentiation and apoptosis of Eca-109 cells.Furthermore, upregulation of FasL, p38 kinase and caspase-3 as well as downregulation of bcl-2, and Fas may be involved in the apoptosis of Eca-109 cells.展开更多
Objective: To study the combined antitumor effect and possible mechanisms of ursolic acid with 5-fluorouracil (5-FU) on human esophageal carcinoma cell Eca-109 in vitro. Methods: Eca-109 cells were treated with ur...Objective: To study the combined antitumor effect and possible mechanisms of ursolic acid with 5-fluorouracil (5-FU) on human esophageal carcinoma cell Eca-109 in vitro. Methods: Eca-109 cells were treated with ursolic acid (10-50 μmol/L) and/or 5-fluorouracil (48.0-768.8 μmol/L) for 48 h in vitro. And then cell proliferation was determined by MTT assay. Cell cycle and apoptosis rate were analyzed by flow cytometry (FCM). The morphological changes of apoptosis were observed by fluorescent microscopy. At last the expression of P27kipl, bcl-2 and bax were detected by western blot. Results: Results: In comparison with single agent treatment, the combination of ursolic acid and 5-fluorouracil produced greater efficacy in growth inhibition, cell cycle arrest at G0/G1 phase, and apoptosis induction (P〈0.05). Western blot analysis showed that the combination use of ursolic acid and 5-fluorouracil suppressed the expression of bcl-2 and increased the expressions of bax and P27kip1. Conclusion: Ursolic acid combined with 5-fluorouracil showed adjuvant antiproliferative effects on human esophageal carcinoma cell Eca-109 in vitro, which mainly due to the induction of cell cycle arrest as well as apoptosis.展开更多
AIM: To study the role of P38 kinase in esophageal cancer cell apoptosis induced by genotoxin, cisplatin and the unfolded protein response (UPR) inducer, dithiothreitol (DTT). METHODS: Esophageal carcinoma cell ...AIM: To study the role of P38 kinase in esophageal cancer cell apoptosis induced by genotoxin, cisplatin and the unfolded protein response (UPR) inducer, dithiothreitol (DTT). METHODS: Esophageal carcinoma cell line Eca109 was cultured in RPMI 1640 medium to 70% confluency and treated with either cisplatin, DTT, or cisplatin plus DTT in the presence or absence of P38 inhibitor, SB203580. The untreated cells served as the control. The esophageal carcinoma cell apoptosis was detected by agarose gel DNA ladder analysis and quantified by flow cytometry. The P38 phosphorylation was detected by immunohistochemistry using antibodies specific to phosphorylated P38 protein. RESULTS: (1) Both cisplatin and DTF induced apoptosis in the esophageal cancer cell line Eca109 as shown by DNA ladder formation; (2) As detected by antibodies specific for the phosphorylated P38 protein (p-P38), both cisplatin and DTT treatments activated the stress-activated enzyme, MAP kinase P38. The number of positive cells was about 50% for the treatment groups, comparing to that of 10% for untreated group. DTF treatment, but not cisplatin treatment, induces nuclear localization of p-P38; (3) As measured by flow cytometry, inhibition of P38 activity by SB203580 blocks DTT- and cisplatin-induced apoptosis. The rates for DTT, cisplatin, and DTT plus cisplatin-induced apoptosis were 16.8%, 17.1%, and 21.4%, respectively. Addition of the SB compound during the incubation reduced the apoptotic rate to about 7.6% for all the treatment groups, suggesting that P38 activation is essential for cisplatin- and DTT-induced apoptosis in Eca109 cells. CONCLUSION: (1) Both DTT and cisplatin were able to induce apoptosis in esophageal cancer cell line Eca109; (2) P38 MAP kinase is essential for DTT- and cisplatininduced apoptosis in Eca109 cells; (3) P38 activation may be the common signaling component relaying the multiple upstream signaling events to the downstream cell death program.展开更多
The expression and properties of alkaline phosphatase (ALP) in Eca109 cells, a cell line derived fromhuman esophageal cancer were studied with specific inhibition assay and polyacrylamide gel electrophoresis.The resul...The expression and properties of alkaline phosphatase (ALP) in Eca109 cells, a cell line derived fromhuman esophageal cancer were studied with specific inhibition assay and polyacrylamide gel electrophoresis.The results showed that ALP of Eca109 cells was heat stable and was strongly inhibited by L-pheuylalanine, but slightly inhibited by urea. Preduisolone could causedramatic increase in activity of ALP, but no change in ALP isozyme and concomitant increase in lactic dehydrogenase activity were found after prednisolone treatment. The results suggested that placental alkaline phosphatase as an oncodevelopmental gene product could be expressed ectopically by Eca109 cells and prednisolone could specifically induce increase in its activity.展开更多
基金Supported by the Research Science Foundation of Henan Province, No. 2000180007
文摘AIM: To investigate the effects of 8-Br-cAMP on differentiation and apoptosis of human esophageal cancer cell line Eca-109, and the related gene expression.METHODS: The cultured Eca-109 cells were divided into four groups: E1 group (co-cultured with 8-Br-cAMP for 24 h); E2 group (co-cultured with 8-Br-cAMP for 48 h); C1 group (treated without 8-Br-cAMP for 24 h); and C2 group (treated without 8-Br-cAMP for 48 h). The same concentration of cell suspension of each group was dropped separately onto the slides and nitrocellulose membranes (NCM). The biotin-labeled cDNA probes for c-myc, wild-type (wt) p53, bcl-2 and iNOS were prepared for in situ hybridization. The expressions of epidermal growth factor receptor (EGFR), p38 kinase, FAS, FasL and caspase-3 were detected using immunocytochemistry, and the NOS activity and the ratio of differentiated cells/proliferating cells were examined by cytochemistry. Immunocytochemistry, cytochemistry,and in situ hybridization were separately carried out on both slides and NCM specimens for each group. In addition, TUNEL was used to detect the cell apoptosis rate in each group.RESULTS: The apoptotic rate of E2 group was significantly higher compared to E1 group, while there was no difference in the ratio of differentiated cells/ proliferating cells between E1 and E2 groups. The signals of wt p53 and iNOS were markedly stronger, while the signals of c-myc and EGFR were obviously weaker in E1 group than those in C1 group (P<0.05). Moreover, the signals of wt p53, iNOS, p38 kinase, caspase-3 and NOS activity were significantly stronger, whereas, the signals of bcl-2, c-myc and Fas/FasL were markedly weaker in E2 group than those in C2 group (P<0.05). CONCLUSION: The differentiation and apoptosis of human esophageal cancer cell Eca-109 can be induced after 24- and 48-h treatment with 8-BrcAMP, respectively. Upregulation of wt p53, iNOS and downregulation of c-myc may be associated with differentiation and apoptosis of Eca-109 cells.Furthermore, upregulation of FasL, p38 kinase and caspase-3 as well as downregulation of bcl-2, and Fas may be involved in the apoptosis of Eca-109 cells.
基金supported by the grants from the Natural science Foundation Project of Chongqing Sci & Tech Committee (CSCT, 2006BB5297)
文摘Objective: To study the combined antitumor effect and possible mechanisms of ursolic acid with 5-fluorouracil (5-FU) on human esophageal carcinoma cell Eca-109 in vitro. Methods: Eca-109 cells were treated with ursolic acid (10-50 μmol/L) and/or 5-fluorouracil (48.0-768.8 μmol/L) for 48 h in vitro. And then cell proliferation was determined by MTT assay. Cell cycle and apoptosis rate were analyzed by flow cytometry (FCM). The morphological changes of apoptosis were observed by fluorescent microscopy. At last the expression of P27kipl, bcl-2 and bax were detected by western blot. Results: Results: In comparison with single agent treatment, the combination of ursolic acid and 5-fluorouracil produced greater efficacy in growth inhibition, cell cycle arrest at G0/G1 phase, and apoptosis induction (P〈0.05). Western blot analysis showed that the combination use of ursolic acid and 5-fluorouracil suppressed the expression of bcl-2 and increased the expressions of bax and P27kip1. Conclusion: Ursolic acid combined with 5-fluorouracil showed adjuvant antiproliferative effects on human esophageal carcinoma cell Eca-109 in vitro, which mainly due to the induction of cell cycle arrest as well as apoptosis.
基金Supported by the Henan Medical Science and Technology Innovation Proiect. No. 200084
文摘AIM: To study the role of P38 kinase in esophageal cancer cell apoptosis induced by genotoxin, cisplatin and the unfolded protein response (UPR) inducer, dithiothreitol (DTT). METHODS: Esophageal carcinoma cell line Eca109 was cultured in RPMI 1640 medium to 70% confluency and treated with either cisplatin, DTT, or cisplatin plus DTT in the presence or absence of P38 inhibitor, SB203580. The untreated cells served as the control. The esophageal carcinoma cell apoptosis was detected by agarose gel DNA ladder analysis and quantified by flow cytometry. The P38 phosphorylation was detected by immunohistochemistry using antibodies specific to phosphorylated P38 protein. RESULTS: (1) Both cisplatin and DTF induced apoptosis in the esophageal cancer cell line Eca109 as shown by DNA ladder formation; (2) As detected by antibodies specific for the phosphorylated P38 protein (p-P38), both cisplatin and DTT treatments activated the stress-activated enzyme, MAP kinase P38. The number of positive cells was about 50% for the treatment groups, comparing to that of 10% for untreated group. DTF treatment, but not cisplatin treatment, induces nuclear localization of p-P38; (3) As measured by flow cytometry, inhibition of P38 activity by SB203580 blocks DTT- and cisplatin-induced apoptosis. The rates for DTT, cisplatin, and DTT plus cisplatin-induced apoptosis were 16.8%, 17.1%, and 21.4%, respectively. Addition of the SB compound during the incubation reduced the apoptotic rate to about 7.6% for all the treatment groups, suggesting that P38 activation is essential for cisplatin- and DTT-induced apoptosis in Eca109 cells. CONCLUSION: (1) Both DTT and cisplatin were able to induce apoptosis in esophageal cancer cell line Eca109; (2) P38 MAP kinase is essential for DTT- and cisplatininduced apoptosis in Eca109 cells; (3) P38 activation may be the common signaling component relaying the multiple upstream signaling events to the downstream cell death program.
文摘The expression and properties of alkaline phosphatase (ALP) in Eca109 cells, a cell line derived fromhuman esophageal cancer were studied with specific inhibition assay and polyacrylamide gel electrophoresis.The results showed that ALP of Eca109 cells was heat stable and was strongly inhibited by L-pheuylalanine, but slightly inhibited by urea. Preduisolone could causedramatic increase in activity of ALP, but no change in ALP isozyme and concomitant increase in lactic dehydrogenase activity were found after prednisolone treatment. The results suggested that placental alkaline phosphatase as an oncodevelopmental gene product could be expressed ectopically by Eca109 cells and prednisolone could specifically induce increase in its activity.