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 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.
