Comparative Experimental Study Of The Radiosensitization Effect Of Different Platinum Compounds On CNE-2Nasopharygeal Carcinoma Cell Line In Vitro

Objective：To study and compare the radiosensitization ofdifferent platinum compounds, Cisplatin, Carboplatin, Oxaliplatin andNedaplatin on CNE-2human nasopharygeal carcinoma cell line in vitro,withthe application of cell colony formation. Methods： Culture Humannasopharygeal carcinoma cell line CNE-2. The cytotoxicities of Cisplatin,Carboplatin, Oxaliplatin and Nedaplatin on CNE-2were determined in96-well plates with5×103cells each well through WST to obtain IC10andIC50. The IC10of platinum compounds was used as radiation sensitizingworking concentration. Collect CNE-2cells of the log phase. After digesting,resuspending, counting, according to the different ray dose gradient in adish,add cell suspension of corresponding total cell number to the culturedishes. Experiment was divided into normal control group, the irradiationgroup, alone drug group, drug+radiation group;the drug+radiation group isdivided into four subgroups: cisplatin+irradiation group, carboplatin+irradiation group, oxaliplatin+irradiation group, nedaplatin+irradiationgroup. Set three Petri dish for each group. The IC10working concentration ofcisplatin, carboplatin, oxaliplatin, nedaplatin was added in24hours before irradiation with medical linear accelarator in6MV X ray. Each group weregiven0、0.5、1、2、3、4、6、8、10Gy of irradiation dose.The dose rate was412.31cGy/min, SSD=100cm, PDD=97.232%,the irradiation area was30×30cm. Fresh medium was replaced in four hours after irradiation, theCNE-2cells cultured in the incubator at37°C,0.5%CO₂thermostat for14d, records the killing effect of different treatments, calculate the survivalrate, clone formation rate with application of counting colony-formingmethod;the mathematical model of the single-hit multi-target was used to plotsurvival curve （the GraphPad Prism5.0software）. Calculate N, D₀, Dq,SER_D0, SER_Dq, SER_SF2, compare the difference of irradiation alonegroup and drug+radiation group, as well as different drugs+irradiationsubgroup. Results：The IC10of Cisplatin, Carboplatin,Oxaliplatin andNedaplatin on CNE-2were0.28ug/ml and1.201527ug/ml1.43ug/ml and6.301118ug/ml respectively, the IC50were18.78ug/ml and1.56808ug/mlrespectively. The plating efficiency of CNE-2was72%. The value of N, D₀and Dq of CNE-2cells received treatment of radiation alone were2.305,1.478Gy，1.234Gy respectively; the value of N, D₀, Dq SER_D0、SER_DqandSER_SF2of CNE-2cells received Cisplatin+radiation were2.547,1.011Gy，0.945Gy,1.462,1.678,1.579respectively; those of CNE-2cells receivedCarboplatin+radiation were2.263,0.994Gy,0.812Gy,1.487,1.521,1.796respectively; those of CNE-2cells received Oxaliplatin+radiation were1.306,0.969Gy,0.789Gy,1.524,1.563,1.884respectively; Nedaplatin+radiation were2.098,0.954Gy,0.707Gy,1.549,1.745,2.070respectively.Conclusions：Cisplatin, Carboplatin,Oxaliplatin andNedaplatin haveshown the radiosensitizing effect in vitro on Nasopharygeal CarcinomaCNE-2human nasopharygeal carcinoma cell line respectively, On theconditon of the same cell cytotoxicity, Nedaplatin has the most radiosensitioneffect,the next is Oxaliplatin and Carboplatin.The Cisplatin was the worst.