miR-512-3p在乳腺癌中的表达及其功能研究

  目的  观察miR-512-3p在浸润性乳腺癌和癌旁组织中的表达,以及对乳腺癌细胞系MDA-MB-231增殖、凋亡、周期和克隆形成能力的影响,并分析其可能机制。  方法  运用荧光定量PCR检测浸润性乳腺癌和癌旁组织中的miR-512-3p的表达量。运用MTT法、流式细胞仪和平板克隆形成实验分析miR-512-3p对细胞增殖、凋亡、周期和克隆形成能力的影响。通过TargetScan、PicTar和miRanda软件寻找miR-512-3p可能靶基因,应用RT-PCR和Western blot技术进行验证。  结果  乳腺癌组织中miR-512-3p表达明显低于正常组织(P < 0.05)。MTT试验中,72 h浓度为100 nmol/L时,miR-512-3p对乳腺癌细胞增殖的抑制作用最明显,抑制率为45.38%。miR-512-3能明显诱导细胞发生早期凋亡(9.32±0.41)%,与空白对照组(3.1±0.54)%,负对照组(2.9±0.39)% 比较,差异有统计学意义(P < 0.05)。与空白对照组比较,G₀/G₁期细胞明显增多,G₂/M期细胞明显减少(P < 0.05)。平板克隆试验显示过表达miR-512-3p可显著抑制细胞的克隆形成能力,并与对照组差异性显著。荧光定量PCR和Western bolt实验结果显示100 nmol/L miR-512-3p显著抑制c-FLIP mRNA和蛋白表达水平。  结论  miR-512-3p在乳腺癌组织中表达明显低于正常组织,其可能通过作用于下游基因c-FLIP抑制乳腺癌细胞株MDA-MB-231的增殖和克隆形成能力,诱导凋亡,其在肿瘤发生发展中可能担任着抑癌基因的角色,可能成为未来乳腺癌诊断和治疗的一个新的靶点。      

Bmi-1与miR-221-3P在乳腺癌组织和细胞中的表达及相互调控关系

目的:探讨Bmi-1与miR-221-3P在乳腺癌组织及细胞中的表达水平及相互调控关系。方法:运用RT-PCR检测Bmi-1与miR-221-3P在乳腺癌组织、癌旁组织及MCF-7、MCF-10a细胞中的相对表达水平。运用统计学方法探讨两者的相关性。运用Targetscan软件分析Bmi-1与miR-221-3P存在的结合位点,构建双荧光报告基因载体验证Bmi-1与miR-221-3P的相互结合作用。Western-blotting检测乳腺癌组织及细胞中Bmi-1蛋白的相对表达水平。结果:Bmi-1在乳腺癌组织及MCF-7细胞中呈高表达,而miR-221-3P的表达水平明显下调,两者呈负相关性,相关系数为r=-0.826。在转染克隆有Bmi-1基因3' UTR质粒的实验中,miR-221-3P组与空白组、miR-221-3P抑制剂组、NC组、NC抑制剂相比较,P＜0.05,差异极显著。降低Bmi-1的表达水平之后,miR-221-3P的表达水平显著上调。结论:Bmi-1在乳腺癌组织和细胞中呈高表达,miR-221-3P在乳腺癌组织和细胞中呈低表达,miR-221-3P负性调控Bmi-1的表达,为阐明乳腺癌的发病机制指明方向。     

miR-199a-3p在乳腺癌中的表达及其作用

背景与目的：多种微小RNA(microRNA,miRNA)在乳腺癌中异常表达,在乳腺癌的发生、发展中起重要作用。miRNA可能是治疗乳腺癌的新靶点。该研究旨在探讨miR-199a-3p在乳腺癌中的表达水平,及其对乳腺癌癌细胞增殖和凋亡的影响。方法：运用实时定量聚合酶链式反应(quantitative real-time polymerase chain reaction,QRT-PCR)检测乳腺癌患者癌组织、癌旁正常组织、人乳腺癌细胞和人乳腺细胞中miRNA-199a-3p的表达水平,miR-199a-3p mimic(或inhibitor)转染乳腺癌细胞MDA-MB-231过表达(或沉默)miR-199a-3p的表达后,通过MTT法检测细胞增殖能力,Hoechst染色法和caspase-3活力测试检测细胞凋亡情况。结果：相对癌旁正常组织和人正常乳腺细胞,miR-199a-3p在乳腺癌患者癌组织和人乳腺癌细胞中表达下调。在MDA-MB-231中转染miR-199a-3p mimic过表达miR-199a-3p可抑制细胞增殖,促进其凋亡;在MDA-MB-231中转染miR-199a-3p inhibitor沉默miR-199a-3p可促进细胞增殖,抑制其凋亡。结论：miR-199a-3p在乳腺癌中表达下调,并通过调节乳腺癌细胞增殖和凋亡发挥抑癌作用。     

miR-93-5p和miR-27a-3p在直肠癌组织中的表达及其意义

目的 探讨在直肠癌组织中呈现出特异性表达的miRNA与临床病理分期、肿瘤浸润深度、淋巴结转移等参数之间的关系及其可能的意义。方法 用微阵列基因芯片技术分析未经任何术前放化疗的71例直肠癌患者癌组织与癌旁组织间miRNA表达的区别,筛选出上调的miR-93-5p和下调的miR-27a-3p,扩大样本量后进行qRT-PCR验证,随后进行多种临床病理参数分析并探讨其可能存在的意义。结果 miR-27a-3p的表达在芯片检测中呈现出低表达,但在PCR验证时呈现出了高表达,且数据较为离散;miR-93-5p在两种检测方法中均显示出高表达的特性(癌组织表达量是癌旁组织的3.165倍,P=0.006),并与肿瘤体积(P=0.004)、治疗前癌胚抗原水平(P=0.001)及淋巴结转移数目(r=0.534,P=0.005)具有相关性,其中与治疗前癌胚抗原水平及淋巴结转移阳性组受侵数目存在正相关。结论 在直肠癌组织中存在特异性表达的miRNA。根据miR-93-5p和miR-27a-3p在直肠癌组织中的表达特点,miR-93-5p有望作为新型生物标记物,为直肠癌的临床诊疗提供参考价值。     

miR-6775-3p在乳腺癌细胞中的表达及其对乳腺癌细胞生物学行为的影响

背景与目的：微小RNA（microRNA,miRNA）与肿瘤的发生、发展过程密切相关。探讨miR-6775-3p在乳腺癌细胞系中的表达及其对乳腺癌细胞生物学行为的影响。方法：通过实时荧光定量聚合酶链反应（real-time fluorescence quantitative polymerase chain reaction,RTFQ-PCR）检测4种乳腺癌细胞系MDA-MB-231、MDA-MB-453、MDA-MB-468和BT-549中miR-6775-3p的表达水平,选取miR-6775-3p表达水平最低的乳腺癌细胞系过表达miR-6775-3p后,采用细胞计数试剂盒（cell counting kit-8,CCK-8）法检测细胞的增殖情况,同时采用transwell迁移和侵袭实验分别检测细胞迁移和侵袭能力的变化。通过RTFQ-PCR和蛋白［质］印迹法（Western blot）检测miR-6775-3p过表达的乳腺癌细胞系中细胞周期蛋白依赖性蛋白激酶4（cyclin-dependent protein kinase 4,CDK4）和CDK6,以及侵袭转移标志物基质金属蛋白酶（matrix metalloproteinase,MMP）17和MMP24 mRNA以及蛋白的表达变化。结果：RTFQ-PCR结果显示,乳腺癌细胞系MDA-MB-453中miR-6775-3p的表达最低,在MDA-MB-453细胞中转染miR-6775-3p mimics后,miR-6775-3p的表达水平明显升高（P<0.001）。CCK-8实验结果显示,MDA-MB-453细胞过表达miR-6775-3p后,细胞的增殖能力明显降低（P<0.01）。Transwell迁移和侵袭实验结果显示,MDA-MB-453细胞过表达miR-6775-3p后,细胞的迁移（P<0.001）和侵袭能力（P<0.01）明显降低。RTFQ-PCR和Western blot实验结果显示,CDK4、CDK6及MMP17、MMP24的mRNA表达和蛋白水平均显著降低（P<0.01）。结论：miR-6775-3p可能抑制乳腺癌细胞的增殖、迁移和侵袭能力。     

长链非编码RNA XIST和miR-101-3p在子宫颈癌组织中的表达及关系

目的：探讨长链非编码RNA（LncRNA）XIST和miR-101-3p在子宫颈癌组织中的表达情况及其临床意义。方法：收集58例子宫颈癌和配对的癌旁组织标本,采用实时荧光定量PCR（qPCR）检测组织中LncRNA XIST和miR-101-3p的表达,分析其与子宫颈癌临床病理因素的相关性,并评价其临床意义。结果：与癌旁组织比较,qPCR显示宫颈癌组织中LncRNA XIST的表达明显上调（P < 0.05）,miR-101-3p的表达明显下调（P < 0.05）;且二者在表达水平上呈负相关（r=-0.68,P=0.000）。LncRNA XIST和miR-101-3p的表达均与宫颈癌淋巴结转移、组织大小及临床分期之间存在相关性（P均<0.05）。结论：LncRNA XIST与miR-101-3p的表达呈负相关,可能成为早期筛选宫颈癌的生物标志物和治疗靶点。     

DNA甲基化调控miRNA-328的表达水平与乳腺癌预后的关系分析

目的 探讨DNA甲基化与微小RNA-328（miR-328）表达的关系及miR-328与浸润性乳腺癌临床病理特征和预后的关系。方法 回顾性分析1998年1月至2013年12月从TCGA乳腺癌芯片数据提取的1090例浸润性乳腺癌组织和104例癌旁组织的miR-328表达水平,分析从TCGA_BRCA_hMethyl450芯片数据中获取的775例浸润性乳腺癌组织和98例癌旁组织的miR-328启动子区CpG位点（cg16421621、cg04650403）甲基化率并计算启动子区甲基化与miR-328水平的相关性,从UCSC Genome Browser中的clinical_data_dictionary芯片数据中获取854例有完整临床病理资料及随访数据的乳腺癌标本,分析miR-328表达与临床病理特征及预后的关系,采用Cox回归模型分析影响预后的因素。结果 TCGA数据库1998年1月至2013年12月有miR-328表达量的1194例乳腺癌及癌旁组织中,1090例浸润性乳腺癌组织的miR-328水平为5.224±1.155,低于104例癌旁组织的6.246±0.923,差异有统计学意义（P＜0.01）;775例浸润性乳腺癌组织的miR-328基因启动子区域cg16421621和cg04650403的甲基化率分别为（0.415±0.201）%和（0.193±0.068）%,高于98例癌旁组织的（0.407±0.222）%和（0.094±0.079）%,差异有统计学意义(P＜0.01）;浸润性乳腺癌标本中miR-328的表达量与其启动子区域CG位点（cg16421621、cg04650403）甲基化率呈负相关（r=-0.127, P=0.005）。854例有完整信息的浸润性乳腺癌患者中,miR 328表达水平与淋巴结转移和肿瘤大小有关（P＜0.05）;miR-328低表达组（＜5.462）的中位总生存时间（OS）为7.25年,低于高表达组（≥5.462）的8.75年,差异有统计学意义（P<0.01）。Cox多因素回归分析显示,年龄、淋巴结转移与miR-328表达水平为影响OS的独立因素（P＜0.05）,miR-328高表达组的危险程度低于低表达组（P＜0.01）。结论 浸润性乳腺癌中miR-328表达受其基因启动子区甲基化调控;miRNA-328与浸润性乳腺癌的临床病理特征有关,并能作为影响浸润性乳腺癌预后的危险因素。     

miRNA-31-5p和SATB2的表达对乳腺癌细胞增殖和迁移的影响机制

  目的  探讨微小RNA-31-5p（microRNA-31-5p,miRNA-31-5p）和核基质结合蛋白质2（special AT-rich sequence-binding protein 2,SATB2）在乳腺癌中的表达,以及其对乳腺癌细胞增殖和迁移的影响。  方法  选取2017年3月至2020年12月于天津医科大学总医院收治行外科切除的80例乳腺癌患者的临床病理资料,定量反转录-聚合酶链反应（qRT-PCR）检测乳腺癌组织标本和各细胞系中miRNA-31-5p和SATB2 mRNA表达。双荧光素酶实验证明miRNA-31-5p和SATB2的关系。细胞实验分为正常组（未行任何干预）,miRNA-31-5p-agomir-对照组（细胞转染miRNA-31-5p-agomir-NC）,miRNA-31-5p激动剂组（细胞转染miRNA-31-5p-agomir）,pcDNA3.1组（细胞转染miRNA-31-5p-agomir+pcDNA3.1-SATB2）。EDU染色、Transwell小室实验检测各组细胞的体外增殖与转移活性;裸鼠皮下种植乳腺癌模型检测细胞的体内生长、转移能力;Western blot检测SATB2、E-钙黏蛋白（E-cadherin）和波形蛋白（Vimentin）的表达。  结果  与癌旁组织和乳腺正常细胞相比,miRNA-31-5p在乳腺癌组织和乳腺癌细胞中的表达下降,SATB2 mRNA表达升高;miRNA-31-5p能靶向调控SATB2表达;与正常组相比,miRNA-31-5p激动剂组细胞的体外增殖与转移以及体内生长与转移能力均明显下降,SATB2和Vimentin的表达降低,E-cadherin的表达升高,而转染pcDNA3.1-SATB2后可部分逆转这一抑制作用,差异均具有统计学意义（均P<0.05）。  结论  miRNA-31-5p在乳腺癌中的表达降低,SATB2的表达升高,过表达miRNA-31-5p后能明显抑制MDA-MB-231细胞的体外增殖与转移、体内生长与转移能力,但转染pcDNA3.1-SATB2可部分逆转这一抑制作用。      

TXNIP interaction with the Her-1/2 pathway contributes to overall survival in breast cancer

Previous studies have indicated that Her-2 induction causes a strong decrease in thioredoxin interaction protein (TXNIP) in breast cancer cells. However, little is known regarding the prognostic value of TXNIP in clinical breast cancer patients with anti-Her-2 treatment. Using a tissue microarray, we detected TXNIP and p27 expression in breast cancer tissue, as well as corresponding noncancerous tissues. We found that TXNIP expression was associated with better overall survival (OS) in these 150 breast cancer patients and that TXNIP and Her-2 expression status were significantly inversely correlated (r=-0.334, P<0.001). These results were validated in another 101 breast cancer tissue samples (r=-0.422, P<0.001). Moreover, TXNIP expression increased significantly following treatment of the human breast cancer cell lines BT474 and SK-BR-3 with a Her-1/2 inhibitor. Furthermore, TXNIP transfection induced p27 expression and G₁ cell cycle arrest and apoptosis. Taken together, our findings suggest that TXNIP plays a critical role in anti-Her-1/Her-2 treatment and may be a potential prognostic marker in breast cancer.     

Clinical significance of miR-155 expression in breast cancer and effects of miR-155 ASO on cell viability and apoptosis

Accumulating evidence shows that mircroRNAs (miRNAs) play a vital role in tumorigenesis. miR-155 is one of the most multifunctional miRNAs whose overexpression has been found to be associated with different types of cancer including breast cancer. To further determine the potential involvement of miR-155 in breast cancer, we evaluated the expression levels of miR-155 by real-time PCR and correlated the results with clinicopathological features. Matched non-tumor and tumor tissues of 42 infiltrating ductal carcinomas and 3 infiltrating lobular carcinomas were analyzed for miR-155 expression by real-time PCR. Further, we used an antisense technique to inhibit miR-155 expression in vitro. WST-8 test was performed to evaluate cell viability and apoptosis assay was used to investigate the effect of the miR-155 antisense oligonucleotide (miR-155 ASO) on HS578T cell death. The expression levels of miR-155 were significantly higher in tumor tissues than the levels in matched non-tumor tissues (P<0.001). Up-regulated miR-155 expression was associated with lymph node positivity (P=0.034), higher proliferation index (Ki-67 >10%) (P=0.019) and advanced breast cancer TNM clinical stage (P=0.002). Interestingly, we next found that miR-155 expression levels had close relations with ER status (P=0.041) and PR status (P=0.029). Transfection efficiency detected by flow cytometry was higher than 70%, the WST-8 test showed that viability of HS578T cells was greatly reduced after transfection with miR-155 ASO compared with the scramble (SCR) group or the liposome group. The Annexin V-FITC/PI assay also indicated that transfection with miR-155 ASO promoted apoptosis.     

miR-132-3p靶向负调控PSMD12抑制乳腺癌上皮间质转化

目的:探讨miR-132-3p调控其下游靶点PSMD12（proteasome 26S亚基,non-ATPase 12）对乳腺癌上皮间质转化(epithelial-mesenchymal transformation,EMT)的作用机制。方法:收集乳腺癌组织及乳腺癌细胞系,RT-qPCR及Western blot实验检测miR-132-3p、PSMD12表达水平,Pearson相关性分析来分析miR-132-3p与PSMD12的相关性。将MDA-MB-231细胞分为对照组、miR-NC组和miR-132-3p mimic组。MTT法及EdU实验检测细胞增殖情况,流式细胞术检测细胞凋亡情况。Western blot实验检测细胞E-cadherin、N-cadherin、Vimentin、Snail蛋白表达水平,共焦荧光分析检测E-cadherin与N-cadherin含量,双荧光素酶切报告实验检测miR-132-3p与PSMD12的靶向关系。结果:乳腺癌组织中miR-132-3p表达水平低于癌旁组织,而PSMD12水平高于癌旁组织,且miR-132-3p与PSMD12表达呈负相关。上调miR-132-3p能抑制MDA-MB-231细胞增殖,促进细胞凋亡,抑制N-cadherin、Vimentin、Snail表达,促进E-cadherin表达。miR-132-3p靶向负调控PSMD12。结论:miR-132-3p靶向负调控 PSMD12抑制乳腺癌上皮间质转化。     

LINC02163靶向miR-338-3p影响乳腺癌细胞增殖、侵袭及迁移

背景与目的:长链非编码RNA(long non-coding RNA,lncRNA)已被发现在乳腺癌中失调,与肿瘤恶性行为密切相关。本研究旨在探究LINC02163靶向miR-338-3p对乳腺癌细胞增殖、侵袭及迁移的影响。方法:收集郑州人民医院2020年1月—2021年9月收治的9例乳腺癌患者的乳腺癌组织及距其2 cm外的癌旁组织样本,通过实时荧光定量聚合酶链反应(real-time fluorescence quantitative polymerase chain reaction,RTFQ-PCR)检测组织样本、人正常乳腺上皮细胞系(MCF-10A)和乳腺癌细胞系(MCF-7、BT-20、MDA-MB-231、T47D)中LINC02163的表达。将MDA-MB-231分为control组、sh-NC组、sh-LINC02163组、sh-LINC02163+inhibitor-NC组和sh-LINC02163+miR-338-3p inhibitor组。采用MTT法、transwell实验及划痕实验分别检测MDA-MB-231细胞活力、侵袭及迁移能力。采用蛋白质印迹法(West...     

Identifying microRNAs regulating B7-H3 in breast cancer: the clinical impact of microRNA-29c

Background:

B7-H3, an immunoregulatory protein, is overexpressed in several cancers and is often associated with metastasis and poor prognosis. Here, our aim was to identify microRNAs (miRNAs) regulating B7-H3 and assess their potential prognostic implications in breast cancer.

Methods:

MicroRNAs targeting B7-H3 were identified by transfecting two breast cancer cell lines with a library of 810 miRNA mimics and quantifying changes of B7-H3 protein levels using protein lysate microarrays. For validations we used western immunoblotting and 3′-UTR luciferase assays. Clinical significance of the miRNAs was assayed by analysing whether their expression levels correlated with outcome in two cohorts of breast cancer patients (142 and 81 patients).

Results:

We identified nearly 50 miRNAs that downregulated B7-H3 protein levels. Western immunoblotting validated the impact of the 20 most effective miRNAs. Thirteen miRNAs (miR-214, miR-363*, miR-326, miR-940, miR-29c, miR-665, miR-34b*, miR-708, miR-601, miR-124a, miR-380-5p, miR-885-3p, and miR-593) targeted B7-H3 directly by binding to its 3′-UTR region. Finally, high expression of miR-29c was associated with a significant reduced risk of dying from breast cancer in both cohorts.

Conclusions:

We identified miRNAs efficiently downregulating B7-H3 expression. The expression of miR-29c correlated with survival in breast cancer patients, suggesting a tumour suppressive role for this miRNA.     

乳腺癌患者组织中miR-6861-5p的表达及临床意义

目的:研究乳腺癌患者组织中微小RNA-6861-5p（miR-6861-5p）的表达水平及临床意义。方法:完全随机选取本院2013年7月至2017年7月住院患者乳腺癌组织139例、良性病变组织101例及癌旁组织79例,实时定量PCR检测miR-6861-5p表达水平并分析乳腺癌组织miR-6861-5p的表达与临床病理特征的相关性。以43例完成随访患者治疗前miR-6861-5p表达量的中位数,将其分为miR-6861-5p高表达组（24例）和低表达组（19例）,Log-rank单因素分析比较两组患者的生存期差异。结果:乳腺癌组织中miR-6861-5p的RNA表达水平（9.242±3.188）显著高于良性病变组织（7.224±3.249）（P<0.01）及癌旁组织（7.221±2.594）（P<0.01）,其表达水平与肿瘤分期、淋巴结转移情况及激素受体表达相关（P<0.05）;miR-6861-5p在Luminal B-like型的表达量（10.910±2.386）显著高于TNBC亚型（7.605±2.565）（P<0.001）;miR-6861-5p高表达组的3年生存率低于miR-6861-5p低表达组（P=0.023）。结论:乳腺癌组织中miR-6861-5p的表达水平显著增高,是乳腺癌疾病进展、淋巴结转移及分子分型的潜在生物标志物。     

circ-ERBB2通过抑制miR-136-5p维持乳腺癌中的HER2下游信号促进曲妥珠单抗耐药

目的:探讨circ-ERBB2/miR-136-5p轴是否参与曲妥珠单抗耐药乳腺癌的耐药性分子机制。方法:qPCR法检测曲妥珠单抗敏感和耐药乳腺癌组织,以及HER2-和HER2+乳腺癌组织中circ-ERBB2和miR-136-5p的表达水平。建立小鼠异种移植瘤模型,评估敲低/过表达circ-ERBB2联合过表达/敲低miR-136-5p对乳腺癌细胞成瘤性及对曲妥珠单抗耐药性的影响。生物信息学和双荧光素酶报告基因分析circ-ERBB2与miR-136-5p的序列互作位点。CCK-8细胞增殖能力测定敲低/过表达circ-ERBB2联合过表达/敲低miR-136-5p以及给予曲妥珠单抗治疗对于乳腺癌常规或曲妥珠单抗耐药BT-474（Trast-resist）细胞增殖能力的影响。Western blot法检测敲低/过表达circ-ERBB2联合过表达/敲低miR-136-5p后,对常规或BT-474（Trast-resist）细胞内HER2、p-Akt、p-ERK1/2表达水平的影响。结果:与曲妥珠单抗敏感乳腺癌组织相比,曲妥珠单抗耐药乳腺癌组织中circ-ERBB2的表达水平显著升高,miR-136-5p表达水平显著降低（P<0.01）。无论激素受体表达为阳性或是阴性,与HER2-乳腺癌组织相比,在HER2+乳腺癌组织中circ-ERBB2表达显著上调,miR-136-5p表达水平被显著抑制（P<0.01）。敲低circ-ERBB2的表达或过表达miR-136-5p均能够抑制BT-474（Trast-resist）细胞增殖及其胞内HER2、p-Akt和p-ERK1/2的表达水平（P<0.01）。结论:circ-ERBB2能够通过抑制miR-136-5p参与维持乳腺癌中的HER2下游信号并促进曲妥珠单抗耐药。     

Differential expression of miR-139, miR-486 and miR-21 in breast cancer patients sub-classified according to lymph node status

Purpose

Therapeutic decisions in breast cancer are increasingly guided by prognostic and predictive biomarkers. Non-protein-coding microRNAs (miRNAs) have recently been found to be deregulated in breast cancers and, in addition, to be correlated with several clinico-pathological features. One of the most consistently up-regulated miRNAs is miR-21. Here, we specifically searched for differentially expressed miRNAs in high-risk breast cancer patients as compared to low-risk breast cancer patients. In the same patients, we also compared miR-21 expression with the expression of its presumed target PTEN.

Methods

Both microarray and RT-qPCR techniques were used to assess miRNA expression levels in lymph node-positive and -negative human invasive ductal carcinoma tissues. Simultaneously, PTEN protein expression levels were assessed using immunohistochemistry.

Results

miR-486-5p and miR-139-5p were found to be down-regulated in patients with lymph node metastases, whereas miR-21 was found to be up-regulated in patients with a positive lymph node status. miR-21 expression levels were found to significantly correlate with tumour size (r?=?0.403, p?=?0.009; Spearman’s rank), whereas no relation was found between miR-21 and PTEN expression levels (Kruskal-Wallis test).

Conclusion

Down-regulation of miR-486-5p and miR-139-5p, in conjunction with up-regulation of miR-21, may represent a useful signature for the identification of high-risk breast cancer patients.