Effects Of Nimotuzumab At Different Administration On Radiosensitivity Of Cell Line Eca109of Esophageal Carcinoma

Objective:To investigate the radiosensitivity enhancement of Nimotuzumab at different adminstration times on esophageal squamous cancer Eca109cell line, confirm the best adminstration time.Methods:Esophgeal squamous cancer Eca109cell line was cultures in vitro. With the cells in the logarithmic growth phase, the antiproliferative activity of Nimotuzumab was determined by MTT analysis,and the50%inhibitory concentrations of the cell line was caculated, respectively. The0.2IC50and0.3IC50were needed for the next subjects. The next subjects were divided into5group:control group(O group), radiation group(R group), Nimotuzumab administration before irradiation group(24NR group), Nimotuzumab administration upon irradiation group(NR group), Nimotuzumab administration after irradiation group(24RN group). Cell-survival rates were evaluated by colony-forming assays. Cell-apoptosis and cell-cycle distribution were investigated using flow cytometry.Results:1. Esopheal squamous cancer Eca109cell line exhibited EGFR protein expression.2. The effect of the growth inhibition was not observe by the MTT analysis in the cell line in24、48hours, but was observed in72hours. The IC50was768ug/ml。3. Conogenic radiation survival assays showed:with0.2IC50, the SER of24NR group, NR group,24RN group was1.09、0.99、0.88, with0.3IC50, the SER of24NR group, NR group,24RN group was1.22、1.04、0.98. At two concentrations, the enhanced SER in Nimotuzumab treated cells indicated that24h before irradiation was found to be the optimal administration time for the enhancement of the radiosensitivity. Increasing the concentration of nimotuzumab, the radiosenditivity was inproved.4. The Flow cytometry showed that Nimotuzumab administration before irradiation could obviously decrease S phase arrest. Nimotuzumab enhance radiation-induced apoptosis in cell line, but the optimal administration was24h before irradiation.5.Conclusions:The best radiosensitizing effect was obtained when nimotuzumab was delivered in24hours before irradiation in esophageal squamous cancer Eca109cell line. And increasing the concentration of nimotuzumab, the radiosenditivity was inproved.