Study Of The Antitumor And Irradiation Enhancement Effects Of Oxaliplatin In Human Poor Differentiation Nasopharyngeal Carcinoma In Vitro And In Vivo

Backgrounds and Objective Oxaliplatin is a third-generation platinum compound,there are some distinct differences in mechanism between cisplatin and Oxaliplatin,and oxaliplatin is less toxic.Poorly differentiated carcinoma is the most common histological type,for nasopharyngeal carcinoma,although radiotherapy is the basic therapeutic approach ,chemotherapy is also important for recurrent and metastatic nasopharyngeal carcinoma,so in this work we analyzed the effects of Oxaliplatin in nasopharyngeal carcinoma cell lines in vitro.Methods CNE2 was incubated with Oxaliplatin of virous concentration and time, cell growth inhibition was assessed by MTT-microculture tetrazolium assay, cell-cycle kinetics and apoptosis were analyzed by flow cytometry and microscopy transmission electron.Results Growth of CNE2 cells was significantly inhibited in a dose-dependent and time-dependment fashion. The rate of cell growth inhibition was (95.6±0.7)% after intervention in 100ug/ml oxaliplatin for 48 hours. The cell showed G2/M arrest and apoptosis. When CNE2 cells were treated with Oxaliplatin at the concentration of 0,0.03,4.0,100μg/ml, the rates of CNE2 cell apoptosis were (0.19±0.17)%,(0.37±0.09)%,(5.50±1.08)%,(9.43±0.09)%, respectively. After CNE2 cells were incubated with Oxaliplatin, it shows apoptotic cells with chromatin condensation, chromatin crescent formation, nucleus fragmentation and apoptosis body by transmission electron microscopy .Conclusion Oxaliplatin suppresses the growth of CNE2 cells in vitro by causing cell-cycle arrest and cell apoptosis. Objective To study the antitumor and radiation enhancement effects of oxaliplatin in human nasopharyngeal carcinoma xenografts.Methods BALB/C mice bearing NPC xenografts were randomized into the control group , the group with oxaliplatin alone , the group with radiation alone , the group with both oxaliplatin and radiation. Each group consisted of 7 or 8 mice. The tumors were measured in the longest diameter everyday to calculate the tumor growth delay, oxaliplatin and (or) 10 Gy single dose radiation were used to intervene the mice.Results The time that the longest diameters of all tumors grew from(8±0.3)mm to(16±0.3)mm were (5.20±0.8) d in the control group , (9.0±0.7) d in the group with radiation alone , (12.80±4.9) d in the group with oxaliplatin alone , (20.40±1.14) d in the group combination both oxaliplatin and radiation. Analysis of variance showed that there was significant differences in the control group and in the group with oxaliplatin alone(F =4.412,P =0.01), also in the group with radiation alone and in the group with both oxaliplatin and radiation(F =1.823,P =0.000).Conclusion The tumor growth could be delayed by oxaliplatin and oxaliplatin could increase X-ray efficacy.