热疗联合IL-2逆转人肺腺癌细胞A549/CDDP的作用及其可能机制

Effect and Possible Mechanism of Thermotherapy Combined with IL-2 on Reversing the Drug Resistance of the Human Lung Adenocarcinoma Cell Line A549/CDDP

目的观察热疗联合白介素-2(IL-2)对人肺腺癌细胞株A549/CDDP的耐药逆转作用,并探讨其可能作用机制。方法采用细胞培养技术,分别培养人肺腺癌细胞株A549及其耐药细胞株A549/CDDP。42℃热疗,联合或不联合200 u·m L^(-1)的IL-2,同时在2μg·m L^(-1)的CDDP作用下,分别干预敏感细胞株和耐药细胞株2 h后,采用MTT法检测2种不同细胞对CDDP的敏感性,流式细胞仪间接免疫荧光法检测热疗、IL-2等不同条件作用下细胞中P-糖蛋白(P-gp)、多药耐药蛋白(MRP)、肺耐药蛋白(LRP)的表达差异,以及细胞内荧光药物CDDP的聚集量的变化。结果分别联用热疗、IL-2时,较单用CDDP,A549/CDDP细胞的抑制率得到提高,A549/CDDP细胞P-gp、MRP表达下降,细胞内荧光强度增强,差异均有统计学意义(P均<0.05)。热疗联合IL-2合用CDDP时,A549/CDDP细胞的抑制率进一步提高,A549/CDDP细胞P-gp、MRP表达明显下降,细胞内荧光强度显著增强,差异均有统计学意义(P均<0.05),但LRP的表达差异无统计学意义(P>0.05)。结论热疗、IL-2分别能部分逆转A549/CDDP细胞对CDDP的耐药性;热疗联合IL-2可进一步增强其耐药逆转效应。其逆转耐药机制,推测可能与抑制P-gp、MRP表达,增加细胞内药物CDDP的积聚有关。

Objective To observe the reversal effect of thermotheapy combined with interleukin-2（IL-2）on the drug resistance of human lung adenocarcinoma cell line A549 / CDDP,and to explore its possible mechanism. Meth-ods Human lung adenocarcinoma cell line A549 and its drug resistant cell line A549 / CDDP were cultured by cell culture technique. After under the thermotherapy of 42 ℃,combined or not combined with 200 u·mL - 1 of IL-2, and 2μg·mL - 1 of CDDP,A549 and A549 / CDDP were intervented for 2 hours. The MTT assay was used to detect the sensitivity of cell line A549 and the cell line A549 / CDDP to CDDP,respectively. Flow cytometry detection were also employed to determine the P-glycoprotein（P-gp）,multidrug resistance protein（MRP）,lung resistance pro-tein（LRP）differential expression and CDDP intracellular fluorescence concentration changes in A549 cell line and A549 / CDDP cell line before and after the combined treatment,respectively. Results With thermotherapy or IL-2, the inhibition rate of CDDP to A549 / CDDP cell line was higher than with CDDP only used,the positive expression rate of p-gp and MRP of A549 / CDDP cells decreased,and the intracellular accumulation of CDDP increased,the differences were statistically significant（P ﹤ 0. 05）. Thermotherapy combined with IL-2 could further reverse the drug resistance of A549 / CDDP cell line,the positive expression rate of P-gp and MRP significantly decreased,andnbsp;the accumulation of intracellular CDDP increased more significantly（P ﹤ 0. 05）. But there was no significant differ-ence for the expression of LRP（P ﹥ 0. 05）. Conclusion Thermotherapy and IL-2 can partly reverse the drug re-sistance of human lung adenocarcinoma cell line A549 / CDDP to CDDP,and thermotherapy combined with IL-2 can further enhance its reversal effect of drug resistance. The mechanism of reversing drug resistance ,presumably,re-lated to inhibition of p-gp,MRP expression,and to increased intracellular accumulation of CDDP.