miR-106b靶向调控PTEN促进结直肠癌细胞放射抵抗

目的 阐明miR-106b在结直肠癌细胞放射敏感性中的作用及机制。方法 构建稳定过表达和干扰miR-106b结直肠癌细胞系,通过免疫荧光和平板克隆实验探讨miR-106b对结直肠癌细胞放射敏感性的影响;Western blot检测Caspase-3和γ-H2AX的表达;生物信息学预测miR-106b下游调控的靶基因,双荧光素酶报告系统、荧光定量PCR及Western blot进一步验证。在稳定过表达miR-106b的结直肠癌细胞系中转染pCDNA3.0-PTEN,探讨细胞放射敏感性变化,明确miR-106b是否通过靶向调控PTEN增加结直肠癌细胞放射抵抗。结果 在结直肠癌细胞系过表达miR-106b,经过同等条件的照射处理后,与对照组相比,过表达miR-106b组细胞存活分数升高,放射抵抗增强(P<0.05),Caspase-3及γ-H2AX表达降低。在稳定过表达miR-106b的细胞中上调PTEN后能逆转miR-106b引起的放射抵抗。结论 miR-106b通过靶向抑制PTEN从而诱导结直肠癌细胞放射抵抗,预示着miR-106b-PTEN位点可能为临床提高结直肠癌放疗效果寻找相关靶点提供理论依据。     

miR-203a通过靶向抑制CDK6调控膀胱癌细胞增殖及放射敏感性

目的:探讨miR-203a在膀胱癌(BC)细胞系(RT-112、T24、5637、UM-UC-3细胞)中的表达及对细胞增殖及放射敏感性的影响。方法:将miR-203a mimics、miR-203a inhibitor、CDK6 siRNA、CDK6表达质粒及相应阴性对照(NC)转染入BC细胞中。实时荧光定量PCR检测...     

miR-449a对胰腺癌细胞放射敏感性影响

目的 研究miR-449a对胰腺癌SW1990细胞放射敏感性的影响方法 qRT-PCR检测放疗前后胰腺癌SW1990细胞系中miR-449a的表达变化,利用Lipofectamine 2000转染试剂盒将miR-449a mimics及miR-NC转染到SW1990细胞中,流式细胞术、克隆形成实验检测放射处理后细胞放射敏感性变化。使用TargetScan预测及双荧光素酶报告基因实验证明miR-449a与Cyclin D1的靶向作用,免疫组织化学法观察Cyclin D1在胰腺癌组织和胰腺癌旁5 cm的正常胰腺组织的分布,基因敲除Cyclin D1验证其对胰腺癌细胞放射敏感性的影响。结果 经放射处理后,miR-449a在胰腺癌细胞中的表达量明显降低;过表达miR-449a增加了放射后胰腺癌细胞的凋亡率,并使胰腺癌细胞克隆形成率也明显降低;TargetScan预测及双荧光素酶报告基因实验证实了Cyclin D1是miR-449a的靶标;Cyclin D1蛋白在胰腺癌患者组织中的阳性染色率(70%,35/50)明显高于正常胰腺组织(20%,2/10),Cyclin D1增加了胰腺癌细胞的放射敏感性。结论 miR-449a通过靶向干扰Cyclin D1的表达,促进胰腺癌细胞的放射敏感性。     

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。     

沉默lncRNA HOTTIP通过上调miR-663a表达增加非小细胞肺癌细胞系放射敏感性

目的 探讨lncRNA HOTTIP通过调控miR-663a表达对4个非小细胞肺癌细胞系放射敏感性影响。方法 用0、2、4、6、8 Gy分别照射H838、H157、A549、H1299细胞系,采用克隆形成实验检测细胞存活情况。qRT-PCR检测细胞中HOTTIP和miR-663a表达水平。以A549、H1299细胞为研究对象,沉默HOTTIP表达、过表达miR-663a后用克隆形成实验检测细胞存活情况。流式细胞术检测细胞凋亡情况,Western blot检测Cleaved caspase-3、Cleaved PARP和γ-H2AX表达。双荧光素酶报告基因实验和qRT-PCR检测验证HOTTIP和miR-663a的靶向关系。结果 HOTTIP在放射耐受的H157、A549、H1299细胞中表达上调,miR-663a表达下调。沉默HOTTIP或过表达miR-663a均可抑制A549、H1299细胞存活(放射增敏比分别为1.562、1.507),促进Cleaved caspase-3、Cleaved PARP和γ-H2AX表达,促进放射照射诱导细胞凋亡。miR-663a是HOTTIP的靶基因,HOTTIP可负性调控miR-663a的表达。抑制miR-663a表达可逆转沉默HOTTIP对肺癌细胞系放射敏感性的影响。结论 沉默HOTTIP通过上调miR-663a表达,抑制肺癌细胞系存活,促进其凋亡,从而提高肺癌细胞系的放射敏感性。     

miR-133b靶向HER-2对结肠癌细胞放射敏感性影响

目的 研究miR-133b对结肠癌细胞(SW620细胞)凋亡及放射敏感性影响并探讨其机制。方法 采用脂质体法转染miR-con组(转染miR-con)、miR-133b组(转染miR-133b mimics)、si-con组(转染si-con)和si-HER-2组(转染si-HER-2) SW620细胞,然后进行0、2、4、6、8 Gy照射。使用qRT-PCR、Western blot、流式细胞术、克隆形成实验和双荧光素酶报告基因实验分别检测各组细胞中miR-133b表达、HER-2蛋白表达、细胞凋亡、细胞存活分数和细胞荧光活性。结果 与照射前相比,照后SW620细胞中miR-133b表达降低(P<0.05),HER-2表达升高(P<0.05)。过表达miR-133b、敲减HER-2均可降低SW620细胞存活分数(P<0.05),促进细胞凋亡(P<0.05)。miR-133b可抑制野生型HER-2细胞荧光活性(P<0.05),且可负向调控HER-2蛋白表达。结论 miR-133b可抑制SW620细胞存活,促进细胞凋亡,增强放射敏感性,其机制可能与靶向HER-2有关。     

miR-21靶向抑制RECK对宫颈癌Hela细胞增殖、侵袭和放射敏感性作用

目的:探究miR-21对宫颈癌Hela细胞增殖、凋亡、侵袭以及放射敏感性的影响和潜在作用机制。方法:利用RT-qPCR方法检测宫颈癌组织和相邻非肿瘤组织、正常宫颈上皮细胞(H8)以及宫颈癌细胞系(HeLa、SiHa、ME180)中miR-21表达水平。通过CCK-8检测、Caspase3/7活细胞凋亡检测、伤口愈合试验...     

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 PTPRG-AS1通过靶向miR-124-3p调控肝癌细胞凋亡和放射敏感性的研究机制

目的:探讨lncRNA PTPRG-AS1对肝癌细胞凋亡和放射敏感性的影响及作用机制。方法:培养正常肝细胞L02和肝癌细胞HepG2、SMMC-7721和BEL-7402,qRT-PCR检测细胞中PTPRG-AS1和miR-124-3p表达水平。转染si-PTPRG-AS1、miR-124-3p mimics至HepG2细胞,抑制HepG2细胞中PTPRG-AS1表达或过表达miR-124-3p,流式细胞术检测细胞凋亡,克隆形成实验检测细胞放射敏感性,Western Blot法检测Bcl-2和Bax蛋白表达。生物信息学软件预测PTPRG-AS1与miR-124-3p存在互补的核苷酸序列,双荧光素酶报告基因实验验证PTPRG-AS1与miR-124-3p之间的调控关系。结果:与正常肝细胞L02相比,肝癌细胞HepG2、SMMC-7721和BEL-7402中PTPRG-AS1表达显著升高（P＜0.05）,miR-124-3p表达显著降低（P＜0.05）。抑制PTPRG-AS1或过表达miR-124-3p均可促进肝癌HepG2细胞的凋亡,增强肝癌HepG2细胞的放射敏感性,抑制Bcl-2蛋白表达,促进Bax蛋白表达。PTPRG-AS1负调控miR-124-3p表达。抑制miR-124-3p表达可部分逆转抑制PTPRG-AS1表达对肝癌HepG2细胞凋亡的促进作用以及放射敏感性的增强作用。结论:抑制PTPRG-AS1表达可能通过上调miR-124-3p表达促进肝癌细胞的凋亡并提高其放射敏感性,是肝癌治疗的潜在作用靶点。     

miR-106b enhances cell radioresistance by targeting PTEN in colorectal carcinoma

Objective To investigate the role of miR-106b in the cell radioresistance in colorectal carcinoma (CRC), and unravel the underlying mechanism. Methods The CRC cell lines stably overexpressing and interfering miR-106b were established. The effect of miR-106b upon the CRC cell radiosensitivity was evaluated by cell radiation, immunofluorescence and colony formation assay. The expression levels of Caspase-3 and γ-H2AX were detected by Western blot. The target genes of miR-106b were identified by bioinformatics prediction, which were further validated by dual luciferase assay, fluorescence quantitative PCR and Western blot. The CRC cell lines stably overexpressing miR-106b were transfected with pCDNA3.0-PTEN. The changes of CRC cell radiosensitivity were investigated. Whether miR-106b could increase the radioresistance of CRC cells by targeting PTEN was clarified. Results Compared with the control group (miR-ctr group), the cell surviving fraction was significantly elevated (P<0.05), the radioresistance (P<0.05) was considerably enhanced and the expression levels of Caspase-3 and γ-H2AX were significantly down-regulated (both P<0.05) in the miR-106b overexpression group. PTEN up-regulation in CRC cell lines stably overexpressing miR-106b could reverse the radioresistance induced by miR-106b. Conclusion miR-106b can induce CRC cell radioresistance by inhibiting PTEN, prompting that miR-106b-PTEN might provide theoretical evidence for relevant targets which can enhance the clinical efficacy of radiotherapy.     

PTEN依赖其磷酸酶活性诱导肝癌细胞发生失巢凋亡机制的探讨

目的 研究抑癌基因PTEN对人肝癌SMMC-7721细胞失巢凋亡的影响并探讨其可能的机制。方法 将携有野生型PTEN基因及无磷酸活性的突变型C124A-PTEN基因的真核表达载体转染SMMC-7721细胞,利用Western印迹杂交法,检测PTEN蛋白表达与蛋白激酶B(PKB／Akt)、焦点黏附激酶(FAK)磷酸化水平的变化,并应用流式细胞仪技术和激光共聚焦显微镜技术,分析各种细胞在黏附与失黏附状态下的凋亡。结果 与对照细胞相比,转染野生型PTEN的SMMC-7721细胞中,FAK和Akt的磷酸化水平分别降低了65．2％和89．1％,且失巢凋亡率由9．5％增至31．3％;而转染C124A-PTEN的SMMC-7721细胞中,FAK和Akt的磷酸化水平及失巢凋亡率均无明显变化。结论 抑癌基因PTEN可依赖其磷酸酶活性抑制FAK和Akt的磷酸化,并诱导肝癌细胞发生失巢调亡。     

MiR-20a inhibits cutaneous squamous cell carcinoma metastasis and proliferation by directly targeting LIMK1

Background MicroRNA-20a (miR-20a) plays a key role in tumorigenesis and progression. But its function is reverse in different kinds of malignant tumor, and its role and mechanism in cutaneous squamous cell carcinoma (CSCC) remains unclear. Object To determine the miR-20a’s roles in CSCC and confirm whether LIMK1 is a direct target gene of miR-20a. Methods First miR-20a and LIMK1 expression levels were detected in six pairs of CSCC tissues and corresponding normal skin by qRT-PCR. Then MTT assays and colony formation assays were performed to evaluate the impact of miR-20a on cell proliferation. In addition, scratch migration assays and transwell invasion assays were performed to check miR-20a’s effect on cell metastasis. Since LIMK1 (LIM kinase-1) was predicted as a target gene of miR-20a, the changes of LIMK1 protein and mRNA were measured by western blot and qRT-RCR methods after miR-20a overexpression. Moreover the dual reporter gene assay was performed to confirm whether LIMK1 is a direct target gene of miR-20a. Finally LIMK1 mRNA and miR-20a in other 30 cases of CSCC pathological specimens were determined and a correlation analysis was evaluated. Results The miR-20a significantly low-expressed in CSCC tissues compared with that in matched normal tissues while LIMK1 has a relative higher expression. MiR-20a inhibited A431 and SCL-1 proliferation and metastasis. Both of LIMK1 protein and mRNA levels were downregulated after miR-20a overexpression. The dual reporter gene assays revealed that LIMK1 is a direct target gene of miR-20a. Furthermore, qRT-PCR results of LIMK1 mRNA and miR-20a in 30 cases of CSCC pathological specimens showed miR-20a is inversely correlated with LIMK1 expression. Conclusion Our study demonstrated that miR-20a is involved in the tumor inhibition of CSCC by directly targeting LIMK1 gene. This finding provides potential novel strategies for therapeutic interventions of CSCC.     

MicroRNA-20a promotes non-small cell lung cancer proliferation by upregulating PD-L1 by targeting PTEN

Non-small cell lung cancer (NSCLC) remains one of the most common malignant tumors worldwide. The aim of the present study was to investigate the possibility of microRNA-20a (miR-20a) as a biomarker and therapeutic target for the diagnosis and treatment of NSCLC. Bioinformatics prediction, together with functional validation, confirmed miR-20a bound to programmed death ligand-1 (PD-L1) 3′-untranslated region to upregulate PD-L1 expression. Both miR-20a and PD-L1 could promote the proliferation of NSCLC cells. The expression level of PD-L1 was controlled by PTEN; however, further upstream regulation of PD-L1 expression was largely unknown. The present study showed that miR-20a could not restore the inhibition of PD-L1 expression levels by PTEN. Knockdown of PTEN expression upregulated the expression level of PD-L1 and promoted the proliferation of NSCLC cells. PTEN negatively regulated the Wnt/β-catenin signaling pathway by inhibiting β-catenin and Cyclin D1. Interestingly, PTEN could reverse miR-20a-mediated proliferation of NSCLC cells and the inhibitory effect was similar to that of XAV-939. miR-20a promotes the proliferation of NSCLC cells by inhibiting the expression level of PTEN and upregulating the expression level of PD-L1. It is suggested that miR-20a could be used as a biomarker and therapeutic target for the treatment of NSCLC.     

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.