X射线照射对人鼻咽癌细胞株MDR1及P-gp表达影响的研究

Effect of X-ray irradiation on MDR1 and P-glycoprotein expression of nasopharyngeal carcinoma cell

目的:探讨X射线照射前后鼻咽癌CNE-1细胞多药耐药基因(MDR1)及其糖蛋白(P-gp)的表达随时间变化情况,及其照射与鼻咽癌细胞多药耐药的关系。方法:对CNE-1细胞进行X射线照射。利用RT-PCR检测照射前后细胞MDR1的表达;Western blotting检测照射前后P-gp的表达;MTT法检测照射前后顺铂对细胞的半数抑制率。结果:MTT法检测照射前CNE-1细胞的IC50值为(1.11±0.05)μg/mL,照射后第7、14、21、28和35天的IC50值均比照射前增高,其值分别为(1.56±0.10)、(2.41±0.11)、(3.24±0.13)、(2.65±0.09)和(1.83±0.15)μg/mL;RT-PCR检测照射前CNE-1细胞MDR1的半定量值为0.47±0.02,照射后第7、14、21、28和35天MDR1的表达比照射前明显增高,其值分别为0.63±0.02、0.86±0.05、0.75±0.07、0.57±0.03和0.58±0.04;Westernblotting检测照射前CNE-1细胞P-gp的半定量值为15.55±1.02,照射后第14、21天比照射前明显增高,其值分别为23.29±1.83、28.98±2.14。结论:X射线照射可引起CNE-1细胞MDR1及P-gp表达增强,同时CNE-1细胞对顺铂产生抵抗。

OBJECTIVE： To investigate the variation in the expression of multidrug resistance gene （MDR1） and P-glycoprotein （P-gp） with the time in nasopharyngeal carcinoma （NPC） CNE-1 cell before and after X-radiation, and the connection between radiation and multidrug resistance in nasopharyngeal carcinoma cells. METHODS： Cells were exposed to X-radiation. The expression of MDR1 was examined in CNE-1 cell before and after radiation by reverse transcriptional polymerase chain reaction （RT-PCR）, P-gp was detected by Western blotting, and the IC50 of cells was examined by MTT method. RESULTS： IC50 of CNE-1 was （1. 1±0. 05） μg/mL before radiation by MTT. IC50 heightened on the 7th, 14th, 21st, 28th and the 35th day after radiation, and its value as follows （1.56 ± 0. 10）, （2.41±0.11）,（3.24±0.13）,（2.65±0.09） and （1.83±0.15） μg/mL. Semiquantitative value of MDR1 of CNE-1 before radiation by RT-PCR was 0.47±0. 02. The expression of MDR1 on the 7th, 14th, 21 st, 28th and the 35th day after radiation was obviously heightened, and its value as follows 0. 63±0. 02,0. 86±0.05,0.75±0. 07, 0. 57± 0. 03 and 0. 58 ± 0. 04. Semiquantitative value of P-gp of CNE-1 before radiation by Western blotting was 15.55 ± 1.02. The expression on the 14th and 21st day after radiation was obviously heightened, and its value as follows 23.29± 1.83 and 28. 98±2.14. CONCLUSION： X-radiation induced the over-expression of MDR1 and P-gp in CNE-1 cell,at the same time CNE-1 cell produced resistance to cisplatin.