沉默lncRNA HOTAIR上调miR-17-5p表达增加U87R细胞放射敏感性

目的 探讨lncRNA HOTAIR对胶质瘤U87R细胞和移植瘤放射敏感性影响及潜在作用机制。方法 将阴性对照质粒、沉默HOTAIR质粒、过表达miR-NC质粒、过表达miR-17-5p质粒分别转染到U87R细胞中,记为沉默对照组、沉默HOTAIR组、过表达miR-NC组、过表达miR-17-5p组;以上各组细胞分别用4Gy照射,记为沉默对照+4Gy组、沉默HOTAIR+4Gy组、过表达miR-NC+4Gy组、过表达miR-17-5p+4Gy组;将沉默HOTAIR质粒分别与抑制表达miR-NC质粒、抑制表达miR-17-5p质粒共转染到U87R细胞中,记为沉默HOTAIR+抑制miR-NC组、沉默HOTAIR+抑制miR-17-5p组,转染均用脂质体法。采用qRT-PCR检测miR-17-5p和HOTAIR的表达;细胞克隆形成实验检测瘤细胞放射敏感性影响;流式细胞术检测细胞凋亡;双荧光素酶报告基因检测实验检测荧光活性。结果 HOTAIR在放射抵抗的细胞中高表达;沉默HOTAIR和过表达miR-17-5p可增加U87R细胞放射敏感性且促进放射照射诱导的凋亡。HOTAIR可靶向调节miR-17-5p表达,抑制miR-17-5p逆转了沉默HOTAIR对U87R细胞放射增敏和促进放射诱导的凋亡。结论 沉默lncRNA HOTAIR对胶质瘤细胞具有放射增敏和促放射诱导的凋亡作用,其机制可能与调控miR-17-5p有关。     

沉默长链非编码RNA HOTAIR对直肠腺癌细胞放射敏感性的影响

目的 探讨沉默长链非编码RNA HOTAIR对直肠腺癌细胞株SW480和HCT116细胞增殖、放射敏感性和凋亡的影响。方法 通过实时荧光定量PCR检测直肠腺癌细胞株中lncRNA HOX转录反义RNA (lncRNA HOTAIR)的表达水平。应用RNA干扰技术沉默HOTAIR的表达,分析其在细胞增殖、细胞放射敏感性和凋亡中的作用。对细胞株进行梯度剂量照射后,检测其放射敏感性和细胞凋亡情况。结果 直肠腺癌细胞株SW480和HCT116中的lncRNA HOTAIR的相对表达水平明显高于直肠黏膜细胞系。克隆形成试验结果显示,与对照siRNA转染组比较,在细胞株SW480和HCT116中siRNA-HOTAIR的放射增敏比分别为1.58和1.33。沉默直肠腺癌细胞中的lncRNA HOTAIR可增加直肠腺癌SW480细胞株的凋亡率及放射敏感性。结论 直肠腺癌中lncRNA HOTAIR的表达水平与细胞放射敏感性之间存在相关性,其有可能是预测直肠腺癌细胞放射敏感性的指标之一。放射联合应用siRNA-HOTAIR对直肠腺癌细胞株SW480和HCT116有抑制细胞增殖、诱导凋亡和放射增敏的作用。     

LncRNA MEG3靶向miR-181a-5p调控宫颈癌细胞放射敏感性

目的 研究LncRNA MEG3对宫颈癌细胞放射敏感性的影响,并探讨其作用机制。方法 运用qRT-PCR法检测放射抗性和放射敏感性宫颈癌细胞中LncRNA MEG3的表达;将过表达对照组(转染pcDNA 3.1)、过表达LncRNA MEG3组(转染pcDNA 3.1-LncRNA MEG3)、抑制miR-NC组(转染anti-miR-NC)、抑制miR-181a-5p组(转染anti-miR-181a-5p)、过表达LncRNA MEG3+过表达miR-NC组(共转染pcDNA 3.1-LncRNA MEG3和anti-miR-NC)、过表达LncRNA MEG3+过表达miR-181a-5p组(共转染pcDNA 3.1-LncRNA MEG3和anti-miR-181a-5p),均用脂质体法转染至SiHa细胞;克隆形成实验检测细胞的存活分数;流式细胞术检测细胞的凋亡率;双荧光素酶报告基因检测实验检测细胞的荧光活性;Western blot检测细胞中PTEN、p-Akt、Akt的蛋白表达。结果 与放射敏感组相比,放射抗性宫颈癌组织中LncRNA MEG3的表达明显降低(P<0.05),其表达量与宫颈癌细胞的放射敏感性呈正相关;过表达LncRNA MEG3、抑制miR-181a-5p均可显著增强宫颈癌细胞SiHa放射敏感性,促进凋亡(P<0.05);野生型LncRNA MEG3细胞的荧光活性受miR-181a-5p的抑制。过表达miR-181a-5p逆转了LncRNA MEG3对宫颈癌细胞放射增敏和促凋亡作用及对PTEN/Akt信号通路的调控。结论 长链非编码RNA LncRNA MEG3可增强宫颈癌细胞放射敏感性,其机制可能与靶向miR-181a-5p调控PTEN/Akt 信号通路有关,可为提高宫颈癌的预后提供新方向。     

长链非编码RNA TUG1通过吸附miR-145对XB1702细胞放射敏感性影响

目的 研究长链非编码RNA TUG1对宫颈癌细胞放射敏感性的影响,并探讨其作用机制。方法 运用qRT-PCR法检测宫颈癌细胞XB1702及正常子宫内膜基质细胞ESC中TUG1和miR-145表达。实验分为转染si-NC组、转染si-TUG1、转染si-NC并照射、转染si-TUG1并照射、共转染si-TUG1和anti-miR-NC和共转染si-TUG1和anti-miR-145组。用脂质体法转染至XB1702细胞。克隆形成实验检测各组细胞存活分数,流式细胞术检测各组细胞凋亡。双荧光素酶报告基因检测各组细胞荧光活性。结果 与ESC细胞相比,XB1702细胞中TUG1表达升高,miR-145表达降低;沉默TUG1可显著提高XB1702细胞存活分数、促进凋亡,增强放射敏感性。TUG1可靶向调控miR-145表达,抑制miR-145可逆转沉默TUG1对XB1702细胞的增殖抑制、凋亡促进及增敏作用。结论 沉默长链非编码RNA TUG1可增强宫颈癌细胞放射敏感性,其机制可能与靶向miR-145有关,将可为宫颈癌放疗提供靶点。     

长链非编码RNA TUG1通过吸附miR-145对XB1702细胞放射敏感性影响

目的 研究长链非编码RNA TUG1对宫颈癌细胞放射敏感性的影响,并探讨其作用机制。方法 运用qRT-PCR法检测宫颈癌细胞XB1702及正常子宫内膜基质细胞ESC中TUG1和miR-145表达。实验分为转染si-NC组、转染si-TUG1、转染si-NC并照射、转染si-TUG1并照射、共转染si-TUG1和anti-miR-NC和共转染si-TUG1和anti-miR-145组。用脂质体法转染至XB1702细胞。克隆形成实验检测各组细胞存活分数,流式细胞术检测各组细胞凋亡。双荧光素酶报告基因检测各组细胞荧光活性。结果 与ESC细胞相比,XB1702细胞中TUG1表达升高,miR-145表达降低;沉默TUG1可显著提高XB1702细胞存活分数、促进凋亡,增强放射敏感性。TUG1可靶向调控miR-145表达,抑制miR-145可逆转沉默TUG1对XB1702细胞的增殖抑制、凋亡促进及增敏作用。结论 沉默长链非编码RNA TUG1可增强宫颈癌细胞放射敏感性,其机制可能与靶向miR-145有关,将可为宫颈癌放疗提供靶点。     

lncRNA LINC00909靶向miR-548-3p对结直肠癌细胞放射敏感性的研究

目的 探讨lncRNA LINC00909是否通过靶向miR-548-3p而影响结直肠癌细胞放射敏感性。方法 采用qRT-PCR检测结直肠癌组织、癌旁组织中LINC00909、miR-584-3p的表达量;体外培养结直肠癌细胞SW480、SW620,分别将si-NC、si-LINC00909、miR-NC、miR-584-3p mimics、si-LINC00909与anti-miR-NC、si-LINC00909与anti-miR-584-3p转染至SW480、SW620细胞,用4 Gy照射细胞;克隆形成实验检测细胞存活分数及放射增敏比;MTT检测细胞增殖;Transwell小室实验检测细胞迁移及侵袭;双荧光素酶报告实验验证LINC00909、miR-584-3p的靶向关系。裸鼠皮下移植瘤实验检测干扰LINC00909表达或抑制miR-584-3p表达对照射后移植瘤重量的影响。结果 结直肠癌组织中LINC00909的表达水平显著升高(P<0.05),miR-584-3p的表达水平显著降低(P<0.05);干扰LINC00909表达或miR-584-3p过表达后细胞存活分数明显降低(P<0.05),放射增敏比分别为2.017、1.762,并可抑制增殖、迁移及侵袭(P<0.05);双荧光素酶报告实验证实LINC00909可靶向结合miR-584-3p;干扰LINC00909表达后移植瘤重量显著降低(P<0.05)。共转染anti-miR-584-3p后移植瘤重量显著升高(P<0.05)。结论 干扰LINC00909表达可通过上调miR-548-3p的表达而减弱结直肠癌细胞增殖、迁移及侵袭能力从而增强细胞放射敏感性。     

抑制LINC00958表达调控miR-422a促进结直肠癌细胞凋亡及放射敏感性的机制

目的 探讨lncRNA LINC00958对结直肠癌细胞凋亡及放射敏感性的影响以及其作用机制。方法 将pcDNA、pcDNA-LINC00958、si-NC、si-LINC00958、miR-NC和miR-422a质粒分别转染到SW480细胞中,并分别记为pcDNA组、pcDNA-LINC00958组、si-NC组、si-LINC00958组、miR-NC组和miR-422a组;将anti-miR-NC和anti-miR-422a质粒分别与si-LINC00958共转染到SW480细胞中,并分别记为si-LINC00958+anti-miR-NC组和si-LINC00958+anti-miR-422a组;分别将miR-NC和miR-422a分别转染到WT-LINC00958和MUT-LINC00958组细胞中,检测荧光活性;转染均用脂质体法。采用qRT-PCR检测miR-422a和LINC00958的表达;Western blot检测蛋白表达;流式细胞术检测细胞凋亡;细胞克隆形成实验检测对结直肠癌细胞放射敏感性的影响;双荧光素酶报告基因检测实验检测荧光活性。结果 结直肠癌细胞中LINC00958高表达,miR-422a低表达;抑制LINC00958表达和过表达miR-422a,可促进结直肠癌细胞凋亡,并增加细胞放射敏感性。LINC00958可靶向调节miR-422a表达;抑制miR-422a,逆转了抑制LINC00958表达对结直肠癌细胞的放射增敏和细胞凋亡促进的作用。结论 抑制LINC00958表达,增加结直肠癌细胞的放射敏感性,并促细胞凋亡,其机制可能与调控miR-422a有关,将为结直肠癌治疗提供新靶点和新思路。     

肝激酶B1增强肺癌H460细胞放射敏感性的体内研究

目的 研究肝激酶B1(LKB1)对肺癌H460细胞裸鼠皮下移植瘤放射敏感性的影响。方法 构建肺癌H460细胞裸鼠皮下移植瘤模型,分别给予空载质粒(pEGFP-Ctrl)、照射+空载质粒(IR+pEGFP-Ctrl)、过表达LKB1质粒(pEGFP-LKB1)、照射+过表达LKB1质粒(IR+pEGFP-LKB1)处理;观察移植瘤生长情况,计算抑瘤率及放射增敏比;并采用免疫组织化学和蛋白印记技术检测各组瘤组织中LKB1表达情况,分析LKB1与放射敏感性的关系。结果 相较于pEGFP-Ctrl组,IR+pEGFP-Ctrl组、pEGFP-LKB1组和IR+pEGFP-LKB1组的肿瘤生长都受到不同程度的抑制,抑瘤率分别为31.30%、14.78%和43.48%,其中IR+pEGFP-LKB1组较其他组最为明显。IR+pEGFP-LKB1组LKB1的放射增敏系数为1.18。转染pEGFP-LKB1组的LKB1在免疫组织化学和蛋白印记水平上表达增高,其余组未见LKB1表达。结论 成功构建肺癌H460细胞裸鼠皮下移植瘤模型,LKB1具有增强肺癌H460细胞裸鼠皮下移植瘤放射敏感性作用。     

lncRNA MEG3通过调控miR-21表达增加肺癌细胞放射敏感性

目的 探讨长链非编码RNA (lncRNA) MEG3对肺癌细胞H1299的放射敏感性调控机制。方法 运用qRT-PCR法检测具有放射抗性的H1299细胞中MEG3、miR-21-5p的表达。将过表达对照组(转染pcDNA3.1)、过表达MEG3组(转染pcDNA3.1-MEG3)、抑制miR-NC组(转染anti-miR-NC)、抑制miR-21-5p组(转染anti-miR-21-5p)、过表达MEG3+过表达miR-NC组(转染pcDNA3.1-MEG3和miR-NC)、过表达MEG3+过表达miR-21-5p组(转染pcDNA3.1-MEG3和miR-21-5p mimics)均用脂质体法转染。克隆形成实验检测细胞存活分数,流式细胞术检测细胞凋亡,双荧光素酶报告基因检测实验检测细胞中MEG3与miR-21-5p的结合力。结果 与正常肺上皮细胞相比,H1299细胞中MEG3表达明显降低,miR-21-5p表达明显升高;过表达MEG3或抑制miR-21-5p均可促进H1299细胞凋亡,增强放射敏感性;MEG3可靶向调控miR-21-5p的表达。过表达miR-21-5p可逆转MEG3对H1299细胞放射增强作用。结论 lncRNA MEG3可增强H1299细胞放射敏感性,其机制也许可能与靶向miR-21-5p有关。     

沉默ANO9增加胰腺癌细胞AsPC-1放射敏感性的实验研究

目的 探讨ANO9对胰腺癌细胞AsPC-1放射敏感性的影响,以期为胰腺癌临床放射治疗提供新的增敏靶点。方法 蛋白印迹法检测胰腺癌细胞系(BxPC-3、PANC-1、AsPC-1)和正常胰腺细胞系中ANO9表达水平;慢病素感染构建沉默ANO9的AsPC-1稳转株,并用蛋白印迹法进行验证;MTT检测沉默ANO9对放射照射后AsPC-1细胞活力的影响;平板克隆形成实验检测沉默ANO9对AsPC-1细胞放射敏感性的影响;蛋白印迹法检测沉默ANO9对EGFR/ERK信号蛋白表达的影响。结果 与正常胰腺细胞系相比,3个胰腺癌细胞系中ANO9表达均增加(均P<0.05);沉默ANO9后细胞中ANO9蛋白表达水平较对照组显著降低(P<0.05),成功构建沉默ANO9的AsPC-1稳转株;沉默ANO9后AsPC-1细胞对放射照射的敏感性明显增加,放射增敏比为1.57,细胞中EGFR/ERK信号蛋白EGFR和p-ERK1/2均下调(均P<0.05)。结论 沉默ANO9能够显著增加胰腺癌细胞AsPC-1的放射敏感性,其机制可能与抑制EGFR/ ERK信号转导有关,ANO9可能成为遏制胰腺癌进展的新靶标。     

Inhibiting lncRNA LINC00958 expression promotes apoptosis of colorectal cancer cells and increases the radiosensitivity throuth targeting miR-422a

Objective To investigate the effect of lncRNA LINC00958 on the apoptosis and radiosensitivity of colorectal cancer cells and its underlying mechanism. Methods The pcDNA, pcDNA-LINC00958, si-NC, si-LINC00958, miR-NC, and miR-422a plasmids were transfected into SW480 cells and assigned into the pcDNA group, pcDNA-LINC00958 group, si-NC group, si-LINC00958 group, miR-NC group, miR-422a group, respectively. Anti-miR-NC and anti-miR-422a plasmids were co-transfected into SW480 cells with si-LINC00958, and assigned into the si-LINC00958+anti-miR-NC group and si-LINC00958+anti-miR-422a group. miR-NC and miR-422a were transfected into the WT-LINC00958 and MUT-LINC00958 cells, respectively. The fluorescence activity was detected. Cell transfection was performed by liposome method. The expression levels of miR-422a and LINC00958 were measured by qRT-PCR. The expression levels of proteins were detected by Western Blot. Cell apoptosis was assessed by flow cytometry. The radiosensitivity of colorectal cancer cells was evaluated by cell clone formation assay. The fluorescence activity was detected by dual luciferase reporter assay. Results High expression of LINC00958 and low expression of miR-422a were observed in colorectal cancer cells. Inhibition of LINC00958 expression and overexpression of miR-422a could promote cell apoptosis and increase cell radiosensitivity of colorectal cancer cells. LINC00958 could target the regulation of miR-422a expression. Inhibition of miR-422a reversed the effect of inhibiting the expression of LINC00958 on increasing the radiosensitization and promoting cell apoptosis of colorectal cancer cells. Conclusions Inhibition of LINC00958 expression increases the radiosensitivity and promotes the apoptosis of colorectal cancer cells. The mechanism may be related to the regulation of miR-422a, which will provide new targets and new ideas for the treatment of colorectal cancer.     

LncRAN MEG3 regulates the radiosensitivity of cervical cancer cells by targeting miR-181a-5p

Objective To evaluate the effect of long-chain non-coding RNA MEG3(LncRNA MEG3) on the radiosensitivity of cervical cancer cells, and to explore its underlying mechanism. Methods The expression of LncRNA MEG3 in cervical cancer cells was detected by qRT-PCR. In the overexpression control group (transfected with pcDNA 3.1), LncRNA MEG3 overexpression group (transfected with pcDNA 3.1-LncRNA MEG3), miR-NC inhibition group (transfected with anti-miR-NC), miR-181a-5p inhibition group (transfected with anti-miR-181a-5p), LncRNA MEG3+miR-NC overexpression group (co-transfected with pcDNA3.1-LncRNA MEG3 and anti-miR-NC), LncRNA MEG3+miR-181a-5p overexpression group (co-transfected with pcDNA 3.1-LncRNA MEG3 and anti-miR-181a-5p), all plasmids were transfected into SiHa cells by liposome method. The cell survival fraction was assessed by colony formation assay. The cell apoptosis rate was evaluated by flow cytometry. The cell fluorescence activity was assessed by dual luciferase reporter assay. The expression levels of PTEN, p-Akt and Akt proteins were detected by Western blot. Results Compared with the radiosensitive group, the expression of LncRNA MEG3 was significantly down-regulated in radiation-resistant cervical cancer tissues (P<0.05), and its expression level was positively correlated with the sensitivity of cervical cancer cells. Overexpression of LncRNA MEG3 or inhibition of miR-181a-5p could significantly enhance the irradiation sensitivity and promote the apoptosis of cervical cancer cell line SiHa (both P<0.05). The fluorescence activity of wild-type LncRNA MEG3 cells was inhibited by miR-181a-5p. Overexpression of miR-181a-5p reversed the irradiation sensitization and pro-apoptosis effect of LncRNA MEG3 and the regulation of the PTEN/Akt signaling pathway on cervical cancer cell. Conclusion LncRNA MEG3 can enhance the sensitivity of cervical cancer cells to radiation exposure, probably by targeting the miR-181a-5p and regulating the PTEN/Akt signaling pathway, which will provide a new direction for improving clinical prognosis of cervical cancer patients.     

lncRNA MEG3 increases the radiosensitivity of lung cancer cells by regulating miR-21

Objective To investigate the regulatory mechanism of long-chain non-coding RNA (lncRNA) MEG3 on the sensitivity of lung cancer cell line H1299 to irradiation. Methods The expression of MEG3 and miR-21-5p in lung cancer cell line H1299 was detected by qRT-PCR. Overexpression control group (transfected with pcDNA3.1), MEG3 overexpression group (transfected with pcDNA3.1-MEG3), miR-NC inhibition group (transfected anti-miR-NC), miR-21-5p inhibition group (transfected with anti-miR-21-5p), MEG3 overexpression+miR-NC overexpression group (co-transfected with pcDNA3.1-MEG3 and miR-NC), MEG3 overexpression+miR-21-5p overexpression group (co-transfected with pcDNA3.1-MEG3 and miR-21-5p mimics) were all transfected into H1299 cells by liposome method treated with 4Gy irradiation. Cell survival fraction was detected by colony formation assay. Cell apoptosis was detected by flow cytometry. The binding of MEG3 to miR-21-5p in cells was assessed by dual luciferase reporter assay. Results Compared with normal lung epithelial cells, the expression of MEG3 was significantly decreased, whereas the expression of miR-21-5p was significantly increased in the radioresistant lung cancer cells H1299. Overexpression of MEG3 or inhibition of miR-21-5p could promote the apoptosis and enhance the radiosensitivity of H1299 cells. MEG3 could targetedly regulate the expression of miR-21-5p. Overexpression of miR-21-5p could reverse the enhanced radiosensitivity of MEG3 to H1299 cells. Conclusion LncRNA MEG3 can enhance the sensitivity of lung cancer cells H1299 to irradiation. The mechanism may be related to targeting miR-21-5p.     

miR-34s增强结直肠癌细胞对放射敏感性的作用研究

目的:探讨miR-34s对结直肠癌细胞放射敏感性的影响以及在电离辐射致DNA损伤中的作用。方法:利用实时荧光定量PCR（real-time quantitative fluorescence PCR,qRT-PCR）检测miR-34a/b/c-5p在结直肠癌细胞中的表达水平,以及电离辐射后miR-34a/b/c-5p表达水平变化趋势。基于克隆形成法和单击多靶模型建立细胞存活曲线,分析miR-34a/b/c-5p对结直肠癌细胞放射敏感性的影响。过表达miR-34a/b/c-5p并进行照射,利用免疫荧光法检测照射后γH2AX焦点形成情况,进而分析miR-34a/b/c-5p对电离辐射致DNA损伤的作用。结果:miR-34a/b/c-5p在HCT116细胞中的表达水平明显高于HT29细胞（P＜0.05）。HCT116细胞经4 Gy照射后24 h内,miR-34a/b/c-5p表达水平呈双峰变化趋势。与miR-NC组相比,过表达miR-34a/b/c-5p可显著增加结直肠癌细胞的放射敏感性,miR-34a/b/c-5p组细胞平均致死剂量（D0）和准阈值剂量（Dq）均明显降低,且辐射增敏比（SER）明显增加。过表达miR-34a/b/c-5p可显著增加电离辐射诱导的DNA双链断裂（double strand breaks,DSBs）水平,照射后1 h和8 h γH2AX焦点数明显高于miR-NC组（P＜0.05）。结论:miR-34s为放射响应miRNA分子,过表达miR-34s可增加电离辐射诱导的DNA损伤水平并增强结直肠癌细胞的放射敏感性。     

LncRNA UCA1对肺癌细胞放射敏感性影响及机制研究

目的 研究长链非编码RNA (LncRNA) UCA1对肺癌细胞增殖、凋亡及放射敏感性影响及其机制。方法 运用qRT-PCR法检测肺癌细胞A549、H1299和人正常肺细胞HBE中UCA1、miR-513a-5p表达。将si-con组(转染si-con)、si-UCA1组(转染si-UCA1)、miR-513a-5p组(转染miR-513a-5p mimics)、miR-NC组(转染miR-NC)、IR+si-con组(转染si-con+照射)、IR+si-UCA1组(转染miR-NC+照射)、IR+miR-513a-5p组(转染miR-513a-5p mimics+照射)、IR+miR-NC组(转染miR-NC+照射)、IR+si-UCA1+anti-miR-513a-5p组(共转染si-UCA1和anti-miR-513a-5p+照射)均用脂质体法转染至A549、H1299细胞,然后部分组进行4Gy照射。MTT法检测各组细胞增殖,克隆形成实验检测细胞增敏比,流式细胞术检测各组细胞凋亡,双荧光素没报告基因检测实验检测各组细胞的荧光活性。结果 与HBE细胞相比,A549、H1299细胞中UCA1表达显著升高(P<0.05),miR-513a-5p表达显著降低(P<0.05)。抑制UCA1、过表达miR-513a-5p均可明显抑制A549、H1299细胞增殖、促进凋亡、提高放射敏感性(放射增敏比为1.897、2.146和1.615、1.872)。miR-513a-5p可抑制野生型UCA1细胞的荧光活性,且UCA1可负向调控miR-513a-5p的表达。抑制miR-513a-5p可逆转抑制UCA1对细胞的放射敏感性的增强作用。结论 抑制LncRNA UCA1可增强放射对肺癌细胞敏感性,其机制可能与靶向抑制miR-513a-5p有关。     

circ-PRKDC通过调控miR-505-3p影响肺癌细胞增殖、凋亡和放射敏感性机制研究

目的 探讨circ-PRKDC对肺癌细胞增殖、凋亡和放射敏感性的影响及分子机制。方法 培养正常肺上皮细胞BEAS-2B和肺癌细胞系NCI-H1299、NCI-H2170、NCI-H1975。将NCI-H1299细胞分为si-NC、si-PRKDC、pcDNA-NC、pcDNA-PRKDC、miR-NC、miR-505-3p、anti-miR-NC、anti-miR-505-3p、si-PRKDC+anti-miR-NC、si-PRKDC+anti-miR-505-3p组。RT-qPCR检测circ-PRKDC和miR-505-3p的表达水平;蛋白质印迹法检测蛋白表达;MTT检测细胞增殖;流式细胞术检测细胞凋亡;平板克隆形成实验检测细胞放射敏感性;双荧光素酶报告实验检测circ-PRKDC和miR-505-3p的靶向关系。结果 与BEAS-2B细胞相比,NCI-H1299、NCI-H2170、NCI-H1975细胞circ-PRKDC表达水平升高(3.65、3.10、2.67∶1.00,P<0.05),miR-505-3p表达水平降低(0.42、0.50、0.54∶1.02,P<0.05)。低表达circ-PRKDC后CyclinD1表达水平降低(0.42∶0.81,P<0.05),Cleaved-caspase-3和γ-H2AX表达水平升高[(0.71∶0.33,P<0.05)和(0.89∶0.465),P<0.05];细胞A值降低(0.413∶0.839,P<0.05);细胞凋亡率升高(20.35∶6.21,P<0.05);细胞存活分数降低(P<0.05);β-catenin表达水平降低(0.35∶0.73,P<0.05)。miR-505-3p高表达后CyclinD1表达水平降低(0.34∶0.83,P<0.05),Cleaved-caspase-3(0.65∶0.32,P<0.05)和γ-H2AX (0.96∶0.45,P<0.05)表达水平升高,细胞A值降低(0.386∶0.851,P<0.05),细胞凋亡率升高(16.38∶6.20,P<0.05),细胞存活分数降低(P<0.05)。与miR-NC比较,miR-505-3p组转染circ-PRKDC野生型报告质粒的细胞荧光素酶活性降低(0.44∶1.00,P<0.05)。下调miR-505-3p能逆转circ-PRKDC低表达对NCI-H1299细胞增殖、凋亡和放射敏感性以及β-catenin表达的影响。结论 低表达circ-PRKDC可能通过上调miR-505-3p抑制肺癌细胞增殖,促进凋亡以及增强细胞的放射敏感性,且其可能与Wnt/β-catenin信号通路有关。