长链非编码RNA FTH1P3靶向miR-218降低人肺癌顺铂耐药细胞对顺铂的化疗敏感性

Long non-coding RNA FTH1P3 reduces cisplatin-resistant human lung cancer cell chemosensitivity to cisplatin by targeting miR-218

目的:研究长链非编码RNA铁蛋白重链1假基因3(ferritin heavy chain 1 pseudogene 3,FTH1P3)对人肺癌顺铂(cisplatin,DDP)耐药细胞株(A549/DDP)DDP化疗敏感性的影响,并探究其潜在的分子机制。方法:采用荧光定量PCR检测FTH1P3与miR-218在A549和A549/DDP细胞中的表达。采用MTT法、流式细胞术、Hoechst 33258染色及CASP3活性试验评估细胞对DDP化疗敏感性的影响。采用荧光素酶报告基因和RNA蛋白免疫沉淀试验分析FTH1P3对miR-218的调控作用。结果:与A549细胞相比,A549/DDP细胞中FTH1P3表达上调,而miR-218表达下调(P<0.05)。与si-NC相比,si-FTH1P3增加A549/DDP细胞对DDP的化疗敏感性,表现为半抑制浓度(IC_(50))降低,多药耐药关联蛋白1(multidrug resistance-associated protein 1,MRP1)和ATP结合家族亚家族B成员1(ATP binding cassette subfamily B member 1,ABCB1)mRNA表达下调,细胞生长能力降低、凋亡增加及CASP3活性升高(P<0.05)。FTH1P3直接结合miR-218并抑制其表达(P<0.05)。与NC抑制物相比,miR-218抑制物能够逆转经si-FTH1P3处理的A549/DDP细胞对DDP的化疗敏感性(P<0.05)。结论:FTH1P3在A549/DDP细胞中表达上调,FTH1P3降低A549/DDP细胞对DDP的化疗敏感性,其机制与miR-218表达下调有关。

Objective:To investigate the effect of long non-coding RNA ferritin heavy chain 1 pseudogene 3(FTH1P3)on the chemosensitivity of a human lung cancer cisplatin(DDP)-resistant cell line(A549/DDP)to DDP and to explore the potential underlying molecular mechanisms.Methods:We used quantitative real-time PCR to detect the expression of FTH1P3 and miR-218 in the A549 and A549/DDP cells.We performed MTT assay,flow cytometry analysis,Hoechst 33258 staining,and Caspase-3 activity assay to evaluate the DDP chemosensitivity of the A549/DDP cells.We analyzed the regulatory effect of FTH1P3 on miR-218 via luciferase reporter gene and RNA immunoprecipitation assays.Results:Compared with the A549 cells,the FTH1P3 and miR-218 expressions were up-and downregulated(P<0.05)in the A549/DDP cells,respectively.Compared with the si-NC,si-FTH1P3 increased the DDP chemosensitivity of the A549/DDP cells,showing reduced half-maximal inhibitory concentration(IC_(50)),downregulated multidrug resistance-associated protein 1(MRP1)and ATP-binding cassette subfamily B member 1(ABCB1)mRNA expressions,reduced cell growth ability,and increased apoptosis and CASP3 activity(P<0.05).Moreover,FTH1P3 directly bound to miR-218 and inhibited its expression(P<0.05).Compared with NC-inhibitors,miR-218 inhibitors reversed the DDP chemosensitivity of si-FTH1P3-treated A549/DDP cells(P<0.05).Conclusions:FTH1P3 expression was upregulated in A549/DDP cells,reducing the DDP chemosensitivity of A549/DDP cells through miR-218 expression downregulation-related effect or mechanism.