Expressions of MDR-1 and P-gp in human nasopharyngeal squamous cell carcinoma CNE1 cell line after X-ray exposure / 国际肿瘤学杂志

ABSTRACT

Objective To examine the expressions of multidrug resistance gene (MDR)-1 and P-glycoprotein (P-gp) in nasopharyngeal squamous cell carcinoma CNE1 cell line before and after X-ray exposure.Methods CNE1 cells were exposed to X-ray.After the irradiation,the CNE1 cells were cultured for 24 hours and tested.The mRNA expressions of MDR-1 in CNE1 cells were measured by semi-quantitative real-time polymerase chain reaction (RT-PCR) before and after X-ray exposure,and the protein expressions of P-gp in CNE1 cells were detected by Western blotting.The protein expressions of P-gp in CNE1 cells were observed by confocal microscope before and after X-ray exposure.Results The results of RT-PCR showed that the absorbance (A) values of MDR-1 mRNA in CNE1 cells were 0.17 ±0.01 and 0.34 ±0.03 before and after irradiation,and the difference was statistically significant (t =16.541,P ＜ 0.001).The results of Western blotting showed that the A values of P-gp protein in CNE1 cells were 0.02 ± 0.01 and 0.04 ± 0.01,and the difference was statistically significant (t =4.612,P =0.016).The green fluorescence intensity of P-gp protein in CNE1 cells after X-ray irradiation was higher than that before X-ray irradiation by confocal microscope.Conclusion X-ray irradiation can cause the high expressions of MDR-1 and P-gp in CNE1 cells,suggesting that X-ray irradiation can induce the occurrence of multidrug resistance in CNE1 cells.