DNA hypermethylation of microRNA-34b/c has prognostic value for stage Ⅰ non-small cell lung cancer

Lung cancer is the leading cause of cancer-related death in the world and approximately 30-40% of patients with stage Ⅰ non-small cell lung cancer (NSCLC) die of recurrent disease. miRNA expression profiles can be diagnostic and prognostic markers of lung cancer. Recently, miR-34 family has been shown to be part of the p53 pathway which is frequently involved in lung cancer, and the expression of miR-34 has been reported to be regulated by DNA methylation. In present study, we investigated the correlation between DNA methylation status of miR-34 family and recurrence of stage Ⅰ NSCLC patients. miR-34a and miR-34b/c promoter methylation status were determined by nested methylation-specific PCR in FFPE tumor tissues from 161 patients of stage Ⅰ NSCLC. Furthermore, mature miR-34b and miR-34c expression were analyzed by qRT-PCR in the same panel tissues. Our results revealed that aberrant DNA methylation of miR-34b/c was correlated with a high probability of recurrence (p = 0.026) and associated with poor overall survival (p = 0.010) and disease-free survival (p = 0.017). No significant association was found for miR-34a methylation. Multivariate analysis showed that promoter hypermethylation of miR-34b/c was an independent prognostic factor of stage Ⅰ NSCLC. Moreover, no significant association between mature miR-34b and miR-34c expression and DNA methylation status was found. In conclusion, we have identified promoter hypermethylation of miR-34b/c as a relatively common event in NSCLC and might be a potential prognostic factor for stage Ⅰ NSCLC.     

Epigenetic silencing of microRNA-199a-5p promotes the proliferation of non-small cell lung cancer cells by increasing AKAP1 expression

MicroRNA (miR)-199a-5p expression is downregulated in a variety of malignancies, including non-small cell lung cancer (NSCLC), and its low expression is associated with a poor prognosis. However, to the best of our knowledge, the mechanism underlying miR-199a-5p downregulation in NSCLC and its target effectors remain to be elucidated. The present study revealed the downregulation of miR-199a-5p expression in NSCLC tissues and cell lines compared with in para-carcinoma tissues and a lung epithelial cell line. Further experiments indicated that the methylation levels of the miR-199a promoter were markedly higher in NSCLC tissues compared with in para-carcinoma tissues. The DNA methyltransferase inhibitor 5-Aza-2′-deoxycytidine markedly increased the expression levels of miR-199a-5p in NSCLC cells. Furthermore, it was identified that miR-199a-5p mimics transfection decreased the expression levels of A-kinase anchoring protein 1 (AKAP1) at both the mRNA and protein levels by targeting the 3′ untranslated region of AKAP1 mRNA. The in vitro experiments demonstrated that miR-199a-5p overexpression inhibited the proliferation and tumorigenicity of NSCLC cells, whereas overexpression of AKAP1 partially recovered the malignant phenotypes, suggesting that AKAP1 may be a downstream effector targeted by miR-199a-5p. Collectively, the present findings indicated that miR-199a-5p may be a novel regulator of AKAP1, and that miR-199a-5p may be a potential tumor suppressor in NSCLC.     

MicroRNA-25 regulates chemoresistance-associated autophagy in breast cancer cells,a process modulated by the natural autophagy inducer isoliquiritigenin

Recent findings have revealed that dysregulated miRNAs contribute significantly to autophagy and chemoresistance. Pharmacologically targeting autophagy-related miRNAs is a novel strategy to reverse drug resistance. Here, we report a novel function of isoliquiritigenin (ISL) as a natural inhibitor of autophagy-related miR-25 in killing drug-resistant breast cancer cells. ISL induced chemosensitization, cell cycle arrest and autophagy, but not apoptosis, in MCF-7/ADR cells. ISL also promoted the degradation of the ATP-binding cassette (ABC) protein ABCG2 primarily via the autophagy-lysosome pathway. More importantly, miRNA 3.0 array experiments identified miR-25 as the main target of ISL in triggering autophagy flux. A mechanistic study validated that miR-25 inhibition led to autophagic cell death by directly increasing ULK1 expression, an early regulator in the autophagy induction phase. miR-25 overexpression was demonstrated to block ISL-induced autophagy and chemosensitization. Subsequent in vivo experiments showed that ISL had chemosensitizing potency, as revealed by an increase in LC3-II staining, the downregulation of ABCG2, a reduction in miR-25 expression and the activation of the miR-25 target ULK1. Overall, our results not only indicate that ISL acts as a natural autophagy inducer to increase breast cancer chemosensitivity, but also reveal that miR-25 functions as a novel regulator of autophagy by targeting ULK1.     

miR-138-5p在非小细胞肺癌中的表达及临床意义

目的 探讨微小RNA-138-5p（miR-138-5p）在非小细胞肺癌（NSCLC）中的表达及临床意义。方法 采用实时荧光定量PCR（QPCR）检测102例NSCLC组织和98例癌旁组织中miRNA-138-5p表达， 分析miRNA-138-5p表达与NSCLC临床病理特征（性别、年龄、TNM分期、肿瘤直径和淋巴结转移）的关系；Kaplan-Miere法绘制生存曲线，差异行Log-rank检验；Cox回归模型分析影响总生存（OS）的因素。结果 QPCR检测结果显示，NSCLC组织中miR-138-5p表达水平为0.42±0.11，显著低于癌旁组织的1.03±0.28，差异具有统计学意义 （P＜0.05）。miR-138-5p表达与TNM分期、肿瘤直径及淋巴结转移均有关（P＜0.05）。miR-138-5p高表达者的中位OS＞36个月，显著高于低表达者的26个月，差异有统计学意义（P＜0.05）。Cox单因素分析显示除miR-138-5p表达外，淋巴结转移、肿瘤直径和TNM分期也与OS有关（P＜0.05）。结论 miR-138-5p在NSCLC中表达下调，其表达与NSCLC发生发展、预后有关， miR-138-5p可作为NSCLC诊断和预后预测新的靶点。     

MiR-204 inhibits human NSCLC metastasis through suppression of NUAK1

Background:

Lung cancer is a leading cause of cancer-related mortality worldwide and non-small-cell lung carcinoma (NSCLC) is responsible for almost 80% of lung cancer-related deaths. Identifying novel molecules that can repress the invasiveness and metastasis of lung cancer will facilitate the development of new antilung cancer strategies. The aim of this study is to determine the roles of NUAK1 (a downstream of Akt) and miR-204 in the invasiveness and metastasis of NSCLC and to reveal the correlation between NUAK1 and miR-204.

Methods:

The expression of NUAK1 in primary human NSCLC tissues was evaluated by immunohistochemistry. Real-time PCR was employed to measure the expression level of miR-204. The effect of NUAK1 and miR204 on the prognosis of NSCLC patients was evaluated by log-rank test. The siRNA transfection was used to manipulate the expression levels of NUAK1 and miR204 in cancer cells. Chemotaxis assay, Scratch assay, and Matrigel invasion assay were performed to evaluate the migration and invasion of cells. Cellular F-actin measurement was used to measure F-actin polymerisation in lung cancer cells. Western blot was used to detect the expression levels of corresponding proteins. The Luciferase assay and RNA immunoprecipitation were used to confirm the actual binding site of miR-204 to 3′UTR of NUAK1.

Results:

Increased expression of NUAK1 is correlated with the invasiveness and metastasis of human NSCLC. Knockdown of NUAK1 inhibited cell migration and invasion. In addition, this study showed that NUAK1 influenced mTOR phosphorylation and induced the phosphorylation of p70S6K1 and eukaryotic initiation factor 4E-binding protein1 (4E-BP1), two downstream targets of mTOR in NSCLC cells. At the same time, decreased expression of miR-204 promoted NSCLC progression and, contrarily, manipulated upregulation of miR-204-inhibited cell migration and invasion. There is clinical relevance between miR-204 downregulation and NUAK1 upregulation in human NSCLC. Furthermore, we found that miR-204 inhibited NSCLC tumour invasion by directly targeting and downregulating NUAK1 expression. Finally, our data suggested that the downregulation of miR-204 was due to hypermethylation of its promoter region.

Conclusions:

Our results indicate that NUAK1 is excessively expressed in NSCLC and plays important roles in NSCLC invasion. The miR-204 acts as a tumour suppressor by inhibiting NUAK1 expression in NSCLC. Both NUAK1 and miR-204 may serve as potential targets of NSCLC therapy.     

长链非编码RNA MSC-AS1通过调控miR-302c-3p/SSX2IP促进非小细胞肺癌细胞增殖

目的:检测长链非编码RNA肌蛋白反义RNA1（musculin antisense RNA 1,MSC-AS1）在非小细胞肺癌（non-small cell lung cancer,NSCLC）组织和细胞中的表达,研究其对肿瘤细胞增殖的影响并探索其机制。方法:采用qRT-PCR技术检测NSCLC肿瘤组织、癌旁组织、肺癌细胞及正常肺上皮细胞中MSC-AS1的表达;分析患者的临床病理资料与MSC-AS1表达的相关性。利用LipofectamineTM2000对肺癌细胞进行转染;MTT及克隆形成实验测定细胞的增殖能力;同时利用qRT-PCR测定细胞中miR-302c-3p及SSX2IP的表达变化。生物信息学方法预测MSC-AS1及miR-302c-3p的下游靶基因;双荧光素酶报告实验验证基因间的靶向结合关系。结果:MSC-AS1在肺癌组织及肺癌细胞(A549、SPC-A1和SK-MES-1)中较癌旁组织及正常肺上皮细胞BEAS-2B中表达升高（P＜0.05）;MSC-AS1的表达水平与癌肿TNM分期、肿瘤大小及淋巴结转移密切相关（P＜0.01）,并提示患者的预后不良（P＜0.01）;敲低MSC-AS1能够抑制肿瘤细胞的增殖（P＜0.05）。MSC-AS1通过miR-302c-3p/SSX2IP轴调控NSCLC细胞的增殖。结论:LncRNA MSC-AS1能够促进NSCLC细胞的增殖并可能成为潜在的治疗靶点。     

Low miR-145 silenced by DNA methylation promotes NSCLC cell proliferation,migration and invasion by targeting mucin 1

MiR-145 has been implicated in the progression of non-small cell lung cancer (NSCLC); however, its exact mechanism is not well established. Here, we report that miR-145 expression is decreased in NSCLC cell lines and tumor tissues and that this low level of expression is associated with DNA methylation. MiR-145 methylation in NSCLC was correlated with a more aggressive tumor phenotype and was associated with poor survival time, as shown by Kaplan-Meier analysis. Additional multivariate Cox regression analysis indicated that miR-145 methylation was an independent prognostic factor for poor survival in patients with NSCLC. Furthermore, we found that restoration of miR-145 expression inhibited proliferation, migration and invasion of NSCLC by the direct targeting of mucin 1 by miR-145. Our results indicate that low miR-145 expression, due to methylation, promotes NSCLC cell proliferation, migration and invasion by targeting mucin 1. Therefore, miR-145 may be a valuable therapeutic target for NSCLC.     

miR-140-5p靶向HDAC7抑制非小细胞肺癌细胞增殖、迁移和侵袭的机制探讨

目的:探讨miR-140-5p靶向组蛋白去乙酰化酶7(histone deacetylase 7,HDAC7)调控非小细胞肺癌（non-small cell lung cancer,NSCLC）细胞增殖、迁移和侵袭的机制。方法:采用qRT-PCR检测人NSCLC组织及癌旁组织中miR-140-5p的表达水平。用miR-140-5p mimic（模拟物）及miR-140-5p NC（阴性对照）转染A549细胞,CCK8法及克隆形成实验检测细胞增殖能力,划痕实验和Transwell实验检测细胞迁移和侵袭能力,双荧光素酶报告基因实验验证miR-140-5p与HDAC7的靶向关系,Western blot检测各组细胞HDAC7及PI3K、p-PI3K、AKT、和p-AKT表达水平。结果:与癌旁组织相比,miR-140-5p在NSCLC组织中的表达水平明显减低,差异有统计学意义（P＜0.01）。与miR-140-5p NC组相比,过表达miR-140-5p后A549细胞在48和72 h的增殖能力明显降低（P＜0.05）;且细胞克隆形成、细胞迁移和侵袭能力均降低（均P＜0.05）,PI3K/AKT信号通路中关键分子p-PI3K和p-AKT蛋白水平明显降低（均P＜0.05)。生物信息学预测HDAC7可能是miR-140-5p的一个靶基因,且双荧光素酶报告结果证实miR-140-5p直接靶向调节HDAC7表达。结论:miR-140-5p通过靶向HDAC7表达进而抑制NSCLC A549细胞的增殖、迁移和侵袭,其机制可能与通过抑制PI3K/AKT信号通路的激活有关。     

miR-10a-5p基因甲基化对卵巢癌铂类耐药的影响

目的 卵巢癌是死亡率最高的妇科肿瘤,较强的化疗耐药性是其预后差的主要原因之一,为了阐明卵巢癌对铂类药物的耐药机制,本研究探讨miRNA基因的甲基化水平对卵巢癌铂类耐药的影响.方法 将卵巢癌组织分为敏感组和耐药组,每组各3例;采用基因芯片技术,对比分析了两组微RNA(microRNA,miRNA)的表达差异;采用实时荧光定量PCR,分别在6例敏感和3例耐药组织、铂类药物敏感(CoC1)和耐药的卵巢癌细胞系(CoC1/DDP),检测了候选miRNA的表达差异;应用Massarray技术,检测敏感组织(15例)与耐药组织(6例)中miRNA基因启动子的甲基化差异;应用生物信息学分析,鉴定目标miRNA的潜在靶基因.结果 以铂类药物敏感的卵巢癌组织样本为对照,利用基因芯片筛选,鉴定了6条在耐药组织样本中出现表达上调的miRNA(miR-493-3p、miR-10a-5 p、miR-16-2-3p、miR-1248、miR-451a、miR-628-3p)和6条表达下调的miRNA(miR-509-3p、miR-1197、miR-376a-3p、miR-1273a、miR-550a-3p、miR-19b-3p).组织验证发现,miR-509-3p、miR-493-3p、miR-10a-5p、miR-16-2-3p和miR-451a,与芯片结果一致;培养细胞研究发现,4条miRNA的表达调控方式与组织芯片结果一致,miR-10a-5p、miR-16-2-3p、miR-1248和miR-628-3p在耐药细胞系中高表达.进一步研究发现,与敏感肿瘤组织相比,耐药组织中miR-10a-5p基因启动子的甲基化水平出现显著降低,P=0.04.结合生物信息学预测HOXA1和USF2为miR-10a-5p与耐药相关的靶基因.结论 与敏感组相比,耐药组miR-10a-5p基因启动子甲基化水平显著降低,miR-10a-5p表达升高,通过抑制 HOXA1和USF2,抑制细胞凋亡,导致铂类化疗药物耐受.     

miR-7-5p通过调控POLE4对非小细胞肺癌细胞增殖侵袭的影响及作用机制

目的 检测miR-7-5p、POLE4在非小细胞肺癌中的表达水平及对非小细胞肺癌细胞增殖、迁移和侵袭的影响。方法 qRT-PCR检测NSCLC组织、癌旁组织、肿瘤细胞、人正常支气管上皮细胞中miR-7-5p和POLE4 mRNA相对表达水平;荧光素酶报告基因分析非小细胞肺癌细胞中miR-7-5p与POLE4的靶向关系;将si-NC、si-POLE4转染至SPC-A-1细胞中设为si-NC组和si-POLE4组,同时设置对照组;MTT法、划痕实验和Transwell实验分别检测各组细胞的增殖、迁移和侵袭。结果 miR-7-5p在非小细胞肺癌组织和细胞中的表达水平降低、POLE4表达水平升高;miR-7-5p可靶向结合POLE4;si-POLE4组培养72 h,细胞OD值显著低于对照组和si-NC组（P<0.05）。si-POLE4组培养48 h细胞的迁移率和穿膜细胞数低于对照组和si-NC组（P<0.05）。结论 miR-7-5p可能通过靶向结合POLE4,抑制非小细胞肺癌细胞的增殖、迁移和侵袭。     

miR-409-3 p调控靶基因Beclin-1抑制小细胞肺癌细胞的自噬进而抑制其生长和转移

目的:探究miR-409-3p及其靶基因对小细胞肺癌细胞自噬、生长和转移的影响.方法:qRT-PCR检测miR-409-3p在HPAEpiC、SBC-5、NCI-H446、HOP-92细胞中的表达,SBC-5细胞中转染miR-409-3p mimic和miR-NC,CCK8法检测转染后细胞增殖,Transwell小室法...     

红景天苷通过miRNA-210-3p/E2F3抑制非小细胞肺癌细胞的增殖和迁移

目的:探讨红景天苷（salidroside，Sal）通过miRNA-210-3p/E2F3对非小细胞肺癌（non-small cell lung cancer，NSCLC）细胞增殖和迁移的影响及作用机制。方法:通过生物信息网站分析miR-210-3p及其靶基因在肺腺癌组织和正常组织中的表达及生存影响。采用免疫组化法检测肺腺癌组织和正常组织中E2F3蛋白的表达；qRT-PCR检测NSCLC细胞中miR-210-3p和E2F3基因表达；Western blot检测NSCLC细胞中E2F3蛋白表达；CCK-8、细胞划痕及克隆形成实验分别检测红景天苷和miR-210-3p对NSCLC细胞增殖、迁移及克隆形成的影响。结果:生物信息网站显示miR-210-3p和E2F3在肺腺癌组织中高表达，且与不良预后相关。Sal以时间-浓度依赖抑制NSCLC细胞的增殖活性（P＜0.05），并显著降低NSCLC细胞的迁移及克隆形成能力（P＜0.05），而低浓度Sal对正常肺上皮细胞的增殖无明显抑制效果。miRNA-210-3p和E2F3表达在NSCLC细胞中上调（P＜0.05），Sal可抑制二者表达（P＜0.05）。与对照组比较，miR-210-3p inhibitor组E2F3表达上调（P＜0.05），miR-210-3p mimics组E2F3表达被抑制（P＜0.05），Sal与miR-210-3p mimics联用进一步抑制了miR-210-3p mimics所致的E2F3表达下调和细胞增殖和迁移的增强作用（P＜0.05）。结论:miR-210-3p和E2F3在肺腺癌中高表达，Sal可通过时间-浓度依赖负调控miRNA-210-3p/E2F3影响 NSCLC细胞的生物学行为，发挥抗癌作用。     

lncRNA HCG18/miR-17-5p/HMGA2 分子轴调控非小细胞肺癌细胞增殖及迁移

[摘要] 目的：探讨lncRNA HCG18/miR-17-5p/HMGA2 分子轴调控非小细胞肺癌（NSCLC）细胞增殖及迁移的分子机制。方法：收集2017 年6 月至2018 年6 月承德市中心医院62 例NSCLC组织及对应的癌旁组织标本,以及NSCLC细胞系A549、NCIH1299、H1650、NCI-H460 和人肺上皮细胞BEAS-B,用qPCR法检测NSCLC组织及细胞系中HCG18、miR-17-5p 及高迁移率族蛋白A2（HMGA2）的表达水平。分别用Si-HCG18、miR-17-5p、miR-17-5p+HCG18 或pcDNA3.1-HMGA2 转染A549 和NCI-H460 细胞,用CCK-8 法、Transwell 实验、Wb检测转染细胞的增殖、迁移、侵袭和HMGA2 及EMT相关蛋白的表达。用双荧光素酶报告基因验证HCG18 对miR-17-5p 或miR-17-5p 对HMGA2 的靶向调控作用。构建敲降HCG18 的A549 细胞小鼠移植瘤模型,观察对移植瘤的影响。结果：lncRNA HCG18 在NSCLC 组织和细胞中均高表达（均P<0.01）,发生淋巴结转移及晚期NSCLC 患者中HCG18 的表达显著提高,且HCG18 高表达的NSCLC患者预后较差、生存率较低（均P<0.01）。转染Si-HCG18 显著抑制NSCLC细胞的增殖、迁移及侵袭能力（均P<0.01）,上调上皮钙黏蛋白的表达（P<0.01）、下调神经钙黏蛋白和波形蛋白的表达（均P<0.01）,小鼠移植瘤体积显著减小（P<0.05）。双荧光素酶报告基因验证了HCG18 与miR-17-5p 靶向结合,以及miR-17-5p 与HMGA2 靶向结合。转染miR-17-5p 后NSCLC 细胞的增殖、迁移及侵袭受到抑制（均P<0.01）,促进上皮钙黏蛋白的表达（P<0.01）、抑制神经钙黏蛋白和波形蛋白的表达（均P<0.01）,而转染miR-17-5p+HCG18 后可抑制miR-17-5p 的作用。结论：HCG18通过调控miR-17-5p/HMGA2 分子轴促进NSCLC细胞的增殖及迁移。