X射线诱导人鼻咽癌细胞耐药基因表达变化的观察

Expressions of drug-resistance gene and its protein of nasopharyngeal carcimoma cells in induction of X-radiation

目的:检测X射线照射前后鼻咽癌CNE-1细胞多药耐药基因(MDR1)、P-糖蛋白(P-gp)、多药耐药相关基因(MRP)及其相关蛋白(MRP)的表达随时间变化的情况。方法:对CNE-1细胞进行X射线照射,总剂量20Gy。利用MTT法检测照射前后顺铂(DDP)对细胞的半数抑制率(IC50),RT-PCR、蛋白质印迹法分别检测照射前和照射第7、14、21、28、35天细胞的MDR1、MRP基因及P-gp、MRP蛋白的表达。结果:照射前CNE-1细胞的IC50值为(1.11±0.05)μg/mL,照射开始第7、14、21、28和35天的IC50值均比照射前增高,P<0.05。照射前CNE-1细胞MDR1和MRP的半定量值分别为0.47±0.02和0.41±0.02,照射开始第7、14、21、28和35天MDR1和MRP的表达比照射前明显增高,P<0.05。照射前CNE-1细胞P-gp和MRP的半定量值分别为15.55±1.02和55.48±1.91,照射开始第14、21、28和35天P-gp表达比照射前明显增高,第7、14、21、28和35天MRP表达比照射前明显增高,P<0.05。结论:CNE-1细胞X射线照射后耐药基因MDR1、MRP及其P-gp、MRP蛋白表达显著增强。

OBJECTIVE： To examine the change in the expres- sions of muhidrug resistance gene （MDR1）, P glycoprotein （P-gp）, MRP gene and MRP with the time in nasopharyngeal carcinoma （NPC） CNE-1 cells before X radiation and following X-radiation. METHODS： The cells were exposed to X-radiation, and the total dose was 20 Gy. ICs0 （inhibitory concentration of drug reducing cell survival by 50%）of cells was examined by the MTT method. The ex- pressions of MDR1 gene and MRP gene were examined in CNE-1 cells before the radiation and the 7th, 14th, 21st, 28th and 35th day after the radiation by reverse transcriptional polymerase chain reac- tion （RT-PCR）, and P gp and MRP were detected by Western blot- ting. RESULTS： IC50 of CNE-1 was （1.11~0.05） /~g/mL before the radiation. ICs0 heightened on the 7th, 14th, 21st, 28th and the 35th day after the radiation, P〈0.05. The semiquantitative values of MDR1 and MRP genes of CNE-1 before the radiation were 0.47 ＋_ 0.02 and 0. 41±0. 02 respectively. The expressions of MDR1 on the 7th, 14th, 21st, 28th and the 35th day after the radiation obviously heightened. The expression of MRP gene obviously heightened, P〈 0.05. The semiquantitative values of P-gp and MRPof CNE-1 before the radiation were 15.55 ± 1.02 and 55.48 ±1.91 respectively. The expressions of P-gp on the 14th, 21st, 28th and 35th day after the radiation obviously heightened, The expression of MRP on the 7th, 14th, 21st, 28th and the 35th day after radiation was obviously heightened,P〈0.05. CONCLUSION： X-radiation can induce the o- ver-expressions of drug resistance gene （MDR1, MRP gene） and its protein （Pgp, MRP）. Chin J Cancer Prey Treat ,2008,15（22） ：1710--1713