Experimental Studies Of Monitoring Antiproliferative Responses To Chemoradiotherapy In Human Esophageal Carcinoma Cell Eca109with¹⁸F-FDG Uptake

Part Experimental studies of monitoring antiproliferative responses to5-FU in human esophageal carcinoma cell Eca109with¹⁸F-FDG uptakeObjective: To establish a useful methodology of¹⁸F-FDG uptake in esophagealcarcinoma cell Eca109, and study the feasibility of monitoring antiproliferative responsesto5-FU in Eca109.Methods: Eca109cells, a cell line of human esophageal squamous cell carcinoma,were used as the experimental materials. Cellular¹⁸F-FDG uptake was determined whenthe conditions were changed in turn, including cell concentration, reaction time,¹⁸F-FDGradioactivity, and glucose concentrations incubation at37℃. Both cellular¹⁸F-FDGuptake and CCK-8were used to monitor antiproliferative responses to5-FU in Eca109at24th,48th hour. The cell ultrastructure was observed under transmission electronmicroscope and the flow cytometry（FCM） was used to detect the apoptosis rate and the cellcycle of Eca109cells treated with5-FU.Results:（1）The basic condition of¹⁸F-FDG uptake in Eca109was （40.63±0.76）%atthe condition of1×10⁶cells,¹⁸F-FDG radioactivity of3.7KBq, glucose concentration of0mmol/L and100min incubation at37℃.（2） In the basic condition, the inhibitory rates ofcellular¹⁸F-FDG uptake were （32.2±3.3）%,（43.15±2.33）%,（51.61±1.88）%,（71.97±2.09）%at24h after the administration of125,250,500and1000μg/ml5-FU, respectively.The difference of inhibitory rates was significant in all groups（P<0.05）.The inhibitoryrates of cellular¹⁸F-FDG uptake were correlated positively with the doses of5-FU（r=0.97,P<0.01）or with the inhibitory rates of CCK-8（r=0.844，P<0.01）.The inhibitory rates of cellular¹⁸F-FDG uptake were （68.14±0.85）%,（76.18±0.92）%,（79.36±0.83）%,（88.97±0.25）%at48h after the administration of125,250,500and1000μg/ml5-FU,respectively. The difference of inhibitory rates was significant in all groups（P<0.05）. Theinhibitory rates of cellular¹⁸F-FDG uptake were correlated positively with the doses of5-FU（r=0.969, P<0.01）or with the inhibitory rates of CCK-8（r=0.831, P<0.01）.（3）Transmission electron microscope showed that5-FU could induce cell apoptosis andnecrosis.（4）Flow cytometry showed the arrest of G0/G1phase and a sub-G1cell peakwere caused by5-FU. The apoptosis rates detected by FCM were （2.2±0.32）%,（8.6±0.39）%,（14.6±1.61）%,（29.7±2.27）%at48h after the administration of0,125,500and1000μg/ml5-FU, respectively. The difference of apoptosis rates was significant in allgroups（P<0.05）.Conclusion:5-FU inhibited the growth of Eca109cells. The inhibitory rate of cellular¹⁸F-FDG uptake, the inhibitory rate of CCK-8and the apoptosis rate showed by FCM allcould evaluate the inhibitory effect of5-FU on Eca109.PartⅡ Experimental studies of monitoring antiproliferative responses toradiotherapy in human esophageal carcinoma cell Eca109with¹⁸F-FDG uptakeObjective: To study the feasibility of monitoring antiproliferative responses toradiotherapy in human esophageal carcinoma cell Eca109with¹⁸F-FDG uptake.Methods: Eca109cells, a cell line of human esophageal squamous cell carcinoma,were used as the experimental materials. Both cellular¹⁸F-FDG uptake and CCK-8wereused to monitor antiproliferative responses to different exposure dose of radiotherapy inEca109at24th,48th hour. The cell ultrastructure was observed by transmission electronmicroscope and the flow cytometry was used to detect the apoptosis rate and the cell cycleof Eca109cells treated with radiotherapy.Results:（1） In the basic condition, the inhibitory rates of cellular¹⁸F-FDG uptake were （-6.16±2.92）%,（8.33±3.88）%,（15.73±2.71）%,（22.6±3.46）%at24h after theexposure doses of2,4,6,8Gy, respectively. The difference of inhibitory rates wassignificant in all groups（P<0.05）. The inhibitory rates of cellular¹⁸F-FDG uptake werecorrelated positively with the exposure doses of radiotherapy（r=0.786, P<0.01）. Theinhibitory rates of cellular¹⁸F-FDG uptake were （31.04±3.29）%,（45.13±3.12）%,（51.47±1.36）%,（57.24±2.68）%at48h after the exposure doses of2,4,6,8Gy, respectively.The difference of inhibitory rates was significant in all groups （P<0.05）. And theinhibitory rates of cellular¹⁸F-FDG uptake were correlated positively with the radiationdoses（r=0.964, P<0.01） or with the inhibitory rates of CCK-8at48h （r=0.736，P<0.01）.（2）Transmission electron microscope showed that radiotherapy could induce cell apoptosisand necrosis.（3）Flow cytometry showed the arrest of G2/M phase and a sub-G1cell peakcaused by radiotherapy. The apoptosis rates detected by FCM were （2.5±0.39）%,（9.5±1.56）%,（16.8±2.39）%,（22.3±1.87）%at48h after the exposure doses of0,2,4,8Gy,respectively. The difference of apoptosis rates was significant in all groups（P<0.05）.Conclusion: Radiotherapy inhibited the growth of Eca109cells. The inhibitory rate ofcellular¹⁸F-FDG uptake, the inhibitory rate of CCK-8and the apoptosis rate showed byFCM all could evaluate the inhibitory effect of radiotherapy on Eca109.