Relationship between radioresistance and microRNA in the same genetic background nasopharyngeal carcinoma cells

AIM:To discuss the relationship between the discrepancy of microRNA (miRNA) and radioresistance in nasopharyngeal carcinoma (NPC) cells CNE-2R and CNE-2 on the basis of validating their different radioresistance. METHODS:Following the exposure of X ray on the clones of CNE-2R and CNE-2 cells,the dose-survival curve and biological characteristics of CNE-2R and CNE-2 cells were determined by SigmaPlot software and the linear quadratic model of survival curve analysis. MicroRNAs were detected by μParafloTM microfluidic chip,hybridization images collected by a laser scanner (GenePix 4000B,Molecular Device) and the signals normalized by a LOWESS filter. The relationship between the discrepancy of NPC radioresistance and the expression of miRNA was predicted according to Targetscan3.1 database (http://www. targetscan. org) after analyzing the data. RESULTS:Compared to CNE-2 cells,37 miRNAs were gain-of-function and 29 miRNAs were loss-of-function in CNE-2R cells among 719 detected miRNAs. 12 miRNAs that detective value was more than 2 000 and 2 folds than the other were hsa-miR-200b,hsa-miR-224,hsa-miR-26b,hsa-miR-125a-5p,hsa-miR-205,hsa-let-7e,hsa-let-7g,hsa-miR-19b,hsa-miR-24,hsa-miR-103,hsa-miR-106b and hsa-miR-93. Data showed that the distinct discrepancy of miRNAs was related to radioresistance. CONCLUSION:The discrepancy of miRNAs is present in different radioresistant NPC cell lines and related to radioresistance.