Long Non-Coding RNA NORAD Inhibits Breast Cancer Cell Proliferation and Metastasis by Regulating miR-155-5p/SOCS1 Axis

PurposeNon-coding RNA activated by DNA damage (NORAD) has been reported to be a cancer-related long non-coding RNA (lncRNA) implicated in the progression of several cancers; however, its role in breast cancer (BC) has not yet been clarified.MethodsQuantitative real-time polymerase chain reaction was used to examine NORAD, microRNA (miR)-155-5p, and suppressor of cytokine signaling 1 (SOCS1) mRNA expression levels. Western blotting was used to analyze SOCS1 protein expression. The malignancy of BC cells was assessed using the cell counting kit-8 (CCK-8), BrdU, and Transwell assays. Bioinformatics analysis, RNA immunoprecipitation assay, and dual-luciferase reporter gene assays were used to verify the targeted relationship between NORAD and miR-155-5p. Additionally, the regulatory effects of NORAD and miR-155-5p on SOCS1 expression were determined by western blotting.ResultsNORAD expression was significantly reduced in BC cell lines and tissues, and its low expression was associated with poor tumor tissue differentiation. NORAD overexpression repressed BC cell proliferation, migration, and invasion, whereas its knockdown produced the opposite effects. Additionally, miR-155-5p was found to be a target of NORAD, and the biological functions of miR-155-5p and NORAD were counteractive. MiR-155-5p was confirmed to target SOCS1, and SOCS1 was found to be positively regulated by NORAD.ConclusionNORAD suppresses miR-155-5p to upregulate SOCS1, thereby repressing the proliferation, migration, and invasion of BC cells.     

Knockdown of linc00152 inhibits the progression of gastric cancer by regulating microRNA-193b-3p/ETS1 axis

Background: Gastric cancer (GC) is a serious threat for public health worldwide. Long non-coding RNA (lncRNA) linc00152 has been well reported to be an oncogene and a potential biomarker in multiple cancers including GC. However, the molecular mechanisms of linc00152 in GC development need to be further investigated.

Methods: RT-qPCR assay was employed to detect the levels of linc00152, microRNA-193b-3p (miR-193b-3p) and ETS1 mRNA. ETS1 protein level was measured by western blot assay. Cell proliferative, migratory and invasive capacities were assessed by colony formation together with CCK-8 assays, transwell migration and invasion assays, respectively. Bioinformatics analyses and luciferase reporter assay were used to explore whether miR-193b-3p could interact with linc00152 or ETS1 3?UTR. The roles and molecular basis of linc00152 silence on the growth of GC xenograft tumors were tested in vivo.

Results: Linc00152 expression was notably upregulated in GC tissues and cells. The proliferative, migratory and invasive abilities of GC cells were weakened by linc00152 depletion, miR-193b-3p overexpression or ETS1 knockdown. Linc00152 upregulation inhibited miR-193b-3p expression by direct interaction and abolished miR-193b-3p-mediated anti-proliferation, anti-migration and anti-invasion effects in GC cells. ETS1 was a target of miR-193b-3p and linc00152 could promote ETS1 expression by downregulating miR-193b-3p. In vivo experiments further validated that linc00152 knockdown inhibited the growth of GC xenograft tumors by upregulating miR-193b-3p and downregulating ETS1.

Conclusion: Knockdown of linc00152 inhibited GC progression by sequestering miR-193b-3p from ETS1 in vitro and in vivo, elucidating a novel molecular mechanism of linc00152 in promoting GC carcinogenesis.     

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。     

lncRNA MAFG-AS1通过调控miR-11181-3p/GLG1轴促进胃癌AGS细胞迁移、侵袭和有氧糖酵解

目的：探讨lncRNA MAFG-AS1/miR-11181-3p/GLG1分子轴对胃癌（gastric cancer,GC）细胞迁移、侵袭和有氧糖酵解的影响及其可能的机制。方法：选取 MAFG-AS1 相对高表达的 GC 细胞系 AGS 作为研究对象,采用 qPCR 法检测其 MAFGAS1、miR-11181-3p、GLG1的RNA表达水平,Transwell实验、糖酵解分析等检测细胞迁移、侵袭和有氧糖酵解的变化,利用生物信息学分析及双荧光素酶报告基因验证MAFG-AS1、miR-11181-3p、GLG1之间的相互作用关系。结果：敲减MAFG-AS1显著上调miR-11181-3p及下调GLG1的表达（均P<0.01）,并可显著抑制GC细胞迁移、侵袭和有氧糖酵解（均P<0.01）;荧光素酶报告基因证实MAFG-AS1竞争性吸附miR-11181-3p（P<0.01）;抑制miR-11181-3p或过表达GLG1可部分逆转敲减MAFG-AS1对GC细胞迁移、侵袭和有氧糖酵解的抑制作用（均P<0.05或P<0.01）。结论：MAFG-AS1通过miR-11181-3p/GLG1分子轴增强GC迁移、侵袭和有氧糖酵解,可能是GC诊疗的潜在分子靶点。     

Long Noncoding-RNA Component of Mitochondrial RNA Processing Endoribonuclease Promotes Carcinogenesis in Triple-Negative Breast Cancer Cells via the Competing Endogenous RNA Mechanism

PurposeTriple-negative breast cancer (TNBC) is a subtype of breast cancer. Increasing evidence supports that dysregulation of long noncoding RNAs (lncRNAs) plays a vital role in cancer progression. RNA component of mitochondrial RNA processing endoribonuclease (RMRP), a lncRNA, is characterized as a tumor-propeller in some cancers, but its mechanism in TNBC remains poorly understood. This study aimed to determine whether and how RMRP functions in TNBC.MethodsCell proliferation was determined by cell counting kit-8 (CCK-8) and colony formation assays and cell apoptosis by flow cytometry analysis and terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) assay. Cell migration and invasion were determined by transwell assays. RNA-binding protein immunoprecipitation (RIP), luciferase reporter, and RNA pulldown assays were implemented to assess the interaction of RMRP with other molecules in TNBC cells.ResultsRMRP expression was elevated in TNBC cells. RMRP knockdown repressed cell proliferation, migration, and invasion, but induced apoptosis in TNBC. In addition, RMRP was found to target microRNA-766-5p (miR-766-5p) in TNBC cells. Silencing miR-766-5p enhanced cell viability and decreased apoptosis, whereas miR-766-5p overexpression had opposite effects. Furthermore, miR-766-5p was found to bind to yes-associated protein 1 (YAP1). Moreover, miR-766-5p inhibition reversed the repressive effect of RMRP knockdown on the malignant progression of TNBC.ConclusionThe present study manifested that RMRP promotes the growth, migration, and invasion of TNBC cells via the miR-766-5p/YAP1 axis. These findings provide novel perspectives for TNBC treatment.     

MiR-1301-3p inhibits human breast cancer cell proliferation by regulating cell cycle progression and apoptosis through directly targeting ICT1

Background

MiRNAs regulate a variety of biological processes, such as cell proliferation and apoptosis and play critical roles in cancer progression. Accumulating studies have demonstrated that miR-1301-3p could regulate the development and progression of multiple cancers, but its biological behaviors in breast cancer (BC) are still elusive.

Methods

The expression of miR-1301-3p was determined in BC tissues and cell lines using quantitative real-time PCR analysis. The effects of miR-1301-3p on BC cell growth, proliferation, cell cycle distribution, and apoptosis were also explored in vitro using MTT, colony formation and Flow cytometry assays. The potential target gene of miR-1301-3p was determined by dual-luciferase reporter assay and verified by quantitative real-time PCR and western blot analysis.

Results

We found the expression of miR-1301-3p was observably significantly down-regulated in BC tissues and cell lines. MiR-1301-3p expression in BC tissues was significantly associated with tumor size and clinical stage. Gain-of-function assays demonstrated that miR-1301-3p inhibited the cell growth and proliferation in breast cancer cell lines, MCF-7 and T-47D. Moreover, up-regulation of miR-1301-3p induced cell cycle G0/G1 phase arrest and apoptosis. Mechanistically, up-regulation of miR-1301-3p reduced the expression of CDK4, Cyclin D1, Bcl-2, but elevated the expression of p21, Bad and Bax. ICT1 was confirmed as a direct target of miR-1301-3p. Furthermore, ICT1 overexpression could partially reverse the effects of miR-1301-3p on BC cell proliferation, cell cycle progression and apoptosis.

Conclusion

Our observations suggested that miR-1301-3p inhibits cell proliferation via inducing cell cycle arrest and apoptosis through targeting ICT1, and might be a therapeutic target for BC.

     

沉默INHBA-AS1靶向miR-335-3p抑制外阴鳞状细胞癌细胞增殖、迁移

目的:探讨沉默长链非编码RNA（long non-coding RNA,lncRNA）INHBA反义RNA1（INHBA antisense RNA1,INHBA-AS1）对外阴鳞状细胞癌细胞SW954生物学行为的影响及机制。方法:37例外阴鳞状细胞癌组织中INHBA-AS1、miR-335-3p表达运用qRT-PCR检测,高迁移率族蛋白2（high mobility group AT-hook 2,HMGA2）蛋白的表达运用Western blotting检测。实验分为con组、si-NC组、si-INHBA-AS1组、miR-NC组、miR-335-3p mimic组、si-INHBA-AS1+miR-335-3p inhibitor组。应用CCK-8实验检测SW954细胞增殖抑制率,克隆形成实验检测SW954细胞克隆形成,Transwell实验和划痕实验检测SW954细胞迁移,流式细胞术检测SW954细胞凋亡。双荧光素酶报告实验鉴定INHBA-AS1与miR-335-3p、miR-335-3p与HMGA2的靶向关系。结果:外阴鳞状细胞癌组织中INHBA-AS1、HMGA2蛋白的表达水平远高于癌旁组织,miR-335-3p的表达水平低于癌旁组织（P＜0.05）。转染si-INHBA-AS1沉默INHBA-AS1或转染miR-335-3p mimic过表达miR-335-3p后,miR-335-3p表达水平、SW954细胞抑制率及凋亡率升高,HMGA2蛋白的表达水平、SW954细胞克隆形成数、迁移细胞数及划痕愈合率降低（P＜0.05）。INHBA-AS1靶向miR-335-3p,miR-335-3p靶向HMGA2。沉默INHBA-AS1处理的SW954细胞增殖、迁移、凋亡的影响被抑制miR-335-3p所逆转。结论:沉默外阴鳞状细胞癌细胞SW954中的INHBA-AS1通过miR-335-3p靶向HMGA2,抑制SW954细胞增殖、迁移,并诱导其凋亡。     

LncRNA RMRP silence curbs neonatal neuroblastoma progression by regulating microRNA-206/tachykinin-1 receptor axis via inactivating extracellular signal-regulated kinases

Background: Neuroblastoma is the commonest malignancy in neonates. Long non-coding RNA (lncRNA) RNA component of mitochondrial RNA processing endoribonuclease (RMRP) has been reported to be an oncogenic factor in some malignancies. However, its roles and molecular mechanisms in neuroblastoma progression are poor defined.

Methods: The expression of RMRP, microRNA-206 (miR-206), and tachykinin-1 receptor (TACR1) mRNA was measured by RT-qPCR assay. Protein levels of TACR1, phosphorylated extracellular signal-regulated kinases (ERK) 1/2 (p-ERK1/2) and ERK1/2 were detected by western blot assay. Cell proliferation was assessed by CCK-8 and colony formation assays. Cell migratory and invasive capacities were determined using Transwell migration and invasion assays. The interaction between miR-206 and RMRP or TACR1 was verified by luciferase assay. The roles and molecular mechanisms of RMRP knockdown on the growth of neuroblastoma xenografts were examined in vivo.

Results: RMRP was highly expressed in neuroblastoma tissues. RMRP knockdown inhibited proliferation, migration and invasion in neuroblastoma cells. Moreover, TACR1 was a target of miR-206 and RMRP performed as a molecular sponge of miR-206 to sequester miR-206 from TACR1 in neuroblastoma cells. TACR1 overexpression abrogated the inhibitory effect of RMRP downregulation on neuroblastoma cell progression by activating ERK1/2 pathway. Inhibition of TACR1 and ERK1/2 pathway abated RMRP-mediated pro-proliferation effect in neuroblastoma cells. RMRP knockdown hindered neuroblastoma xenograft growth by regulating miR-206/TACR1 axis via inactivating ERK1/2 pathway in vivo.

Conclusion: RMRP knockdown hindered the tumorigenesis and progression of neuroblastoma by regulating miR-206/TACR1 axis via inactivating ERK1/2 pathway, hinting a potential therapeutic target for neuroblastoma.     

Circular RNA CEP128 promotes bladder cancer progression by regulating Mir-145-5p/Myd88 via MAPK signaling pathway

The present experiment was designed for exploring the regulatory mechanism of circ-CEP128/miR-145-5p/MYD88 axis in bladder cancer. MiRNAs and circRNAs expression data were derived from Gene Expression Omnibus database with bladder tumor tissues and paracarcinoma tissue samples. Differentially expressed genes in tumor were analyzed via R software. Interaction network of differently expressed miRNAs and differently expressed mRNA was established by means of Cytoscape software. CircCEP128 and miR-145-5p expression levels were determined using qRT-PCR. The expression of MAPK signaling-related proteins MYD88, p38, ERK and JNK was examined by western blot. The relationship between circCEP128 and miR-145-5p was validated using RNA immunoprecipitation. The level of cell propagation and migration was determined by CCK8 and wound healing assay, 5-bromo-2′-deoxyuridine assay and migration assay. Cell apoptosis rate and cell cycle were detected via flow cytometry. Tumor xenograft assay was implemented to investigate the function of circCEP128 in vivo. CircCEP128 and MYD88 were overexpressed in bladder cancer based on microarray analysis and miR-145-5p was a potential targeting factor in bladder cancer. CircCEP128 targeted miR-145-5p and miR-145-5p targeted MYD88. Expression of miR-145-5p was decreased in cancer samples. Knockdown of circCEP128 induced the inhibition of cell viability and mobility and cell cycle arrest. Overexpression of miR-145-5p or knockdown of circCEP128 promoted MAKP signaling pathway and related proteins expression. In addition, knockdown of circCEP128 suppressed the growth of bladder cancer tumor tissues in vivo. Overexpression of circCEP128 promoted bladder cancer progression through modulating miR-145-5p and MYD88 via MAKP signaling pathway.     

miR-497-5p通过HMGA2调控食管鳞癌细胞迁移和侵袭

目的:探讨miR-497-5p通过高迁移率族蛋白A2(HMGA2)对食管鳞癌细胞(ESCC)迁移和侵袭能力的影响。方法:利用UALCAN、GEPIA数据库分析miR-497-5p和HMGA2 mRNA在食管癌中的表达。通过生物信息学网站starBase分析miR-497-5p和HMGA2在食管癌样本中表达的相关性。通过双荧光素酶报告基因实验检测miR-497-5p对HMGA2基因的调控。采用细胞划痕实验和Transwell实验分析miR-497-5p通过HMGA2对ESCC细胞迁移和侵袭能力的影响。结果:miR-497-5p在食管癌中的表达明显低于其对照样本(P<0.05),HMGA2 mRNA在食管癌中的表达明显高于其对照样本(P<0.05)。miR-497-5p和HMGA2的表达成负相关,miR-497-5p对靶基因HMGA2具有直接调控作用。miR-497-5p mimic组细胞的迁移和侵袭能力明显低于阴性对照(NC)组(P<0.001);而miR-497-5p mimic+HMGA2组细胞的迁移和侵袭能力与miR-497-5p mimic组相比明显上升(P&l...     

Identification of lncRNA TRPM2-AS/miR-140-3p/PYCR1 axis’s proliferates and anti-apoptotic effect on breast cancer using co-expression network analysis

Breast cancer (BC) is one of the most common malignancies occurring in women worldwide. Weighted gene co-expression network analysis (WGCNA) has not been widely utilized in uncovering the biomarkers which played pivotal roles in BC treatment. This study aimed to verify the proliferative and anti-apoptotic effect of lncRNA TRPM2-AS/miR-140-3p/PYCR1 axis on BC based on WGCNA. WGCNA was applied for determining hub genes using gene expression data gained from breast cancer and adjacent tissues which were downloaded from the Cancer Genome Atlas (TCGA) database. The correlative curves showed the correlation between OS/DFS of BC patients and TRPM2-AS expression or PYCR1 expression based on the data of survival rate of BC patients obtained from the TCGA database. QRT-PCR was employed in detecting the expression levels of TRPM2-AS, miR-140-3p and PYCR1, and western blot analysis was adopted for determination of protein expression level of PYCR1. Dual luciferase assay was applied to verify the targeting relationship between TRPM2-AS and miR-140-3p, as well as miR-140-3p and PYCR1. The roles of TRPM2-AS, miR-140-3p, and PYCR1 in proliferation, migration, and apoptosis of BC cell were identified by CCK-8 assay, cell migration assay and flow cytometry. Hub genes were also gained from WGCNA test. The prognostic study showed a significant negative correlation between the high expression of PYCR1 and TRPM2-AS and the BC survival. QRT-PCR demonstrated that PYCR1 and TRPM2-AS were both overexpressed, while miR-140-3p was greatly down-regulated in BC cell. In addition, it was validated by dual luciferase assay that miR-140-3p directly targeted both TRPM2-AS and PYCR1. Furthermore, down-regulation of TRPM2-AS and PYCR1 inhibited proliferation yet promoted apoptosis of BC cell, and up-regulation of miR-140-3p in BC cell showed the same tendency. Taken together, TRPM2-AS could promote proliferation and inhibit apoptosis of BC cell through TRPM2-AS/miR-140-3p/PYCR1 axis.     

miR-4465 通过靶向下调HMGA1的表达抑制肝细胞癌Hep3B细胞的恶性生物学行为

目的：探讨miR-4465 靶向高迁移率族蛋白A1（HMGA1）对肝细胞癌 Hep3B 细胞增殖、迁移和侵袭能力的影响。方法：收集2020 年5 月至2021 年9 月在皖南医学院第一附属医院确诊为肝细胞癌患者的16 对癌组织和癌旁组织样本，采用qPCR 分析miR-4465 在肝细胞癌组织和Hep3B、Huh7细胞中的表达情况，双荧光素酶报告基因实验验证miR-4465 与HMGA1的调控关系。按转染物的不同将 Hep3B 细胞分为 mimics-NC 组 、miR-4465-mimics 组、inhibitor-NC 组、miR-4465 inhibitor组、si-NC 组、si-HMGA1 组；另外分组转染mimics-NC+pcDNA-NC、miR-4465 mimics+pcDNA-NC 和miR-4465 mimics+pcDNA-HMGA1进行回复实验。采用qPCR和WB法检测各组细胞中HMGA1 mRNA和蛋白水平的变化，CCK-8法检测各组细胞增殖能力的变化，划痕实验检测各组细胞迁移能力的变化，Transwell 实验检测各组细胞侵袭能力的变化。结果：miR-4465 在肝细胞癌组织和细胞中的表达水平显著低于癌旁组织和正常肝细胞（P<0.05或P<0.001）。转染48 h后，过表达miR-4465 的Hep3B细胞增殖、迁移和侵袭能力均显著下降（P<0.05、P<0.01或P<0.001）；敲低miR-4465 后细胞的增殖、迁移和侵袭能力均明显升高（P<0.05、 P<0.01或P<0.001）。双荧光素酶报告实验验证了HMGA1-3''UTR 与miR-4465 的靶向结合关系，miR-4465 可以靶向下调HMGA1 mRNA 和蛋白质的表达（均P<0.01）。过表达HMGA1 能部分逆转过表达 miR-4465 对细胞增殖、迁移、侵袭的抑制作用及HMGA1 表达的抑制作用（均P<0.05）。结论：miR-4465 通过靶向下调HMGA1 在肝细胞癌Hep3B 细胞中的表达，从而抑制Hep3B细胞的恶性生物学行为。     

miR-509-5p通过靶向HMGA2调控非小细胞肺癌H1299细胞增殖、迁移和侵袭及其机制探讨

目的:探讨miR-509-5p通过靶向HMGA2对非小细胞肺癌H1299细胞增殖、迁移和侵袭的调控作用及其机制。方法:体外培养人正常肺细胞株CCD-19LU和肺腺癌细胞株A549、H1299,采用qRT-PCR检测miR-509-5p的表达;转染miR-509-5p mimics构建miR-509-5p过表达的H1299细胞后,采用MTT和克隆形成实验检测细胞的增殖能力,Transwell小室实验检测细胞的迁移和侵袭能力,Western blot检测TWIST1、β-catenin和AXIN1蛋白的表达。通过生物信息学分析预测HMGA2可能是miR-509-5p的靶点,并采用双荧光素酶报告基因系统和Western blot检测miR-509-5p和HMGA2的靶向关系。转染干扰质粒载体pLL2G-shHMGA2构建HMGA2沉默的H1299细胞,采用MTT实验、克隆形成实验和Transwell小室实验检测细胞的增殖、迁移和侵袭能力,Western blot检测TWIST1、β-catenin和AXIN1蛋白的表达。结果:与CCD-19LU细胞相比,A549和H1299细胞中miR-509-5p表达明显降低（P<0.05）,且在H1299细胞中低于在A549细胞中的表达（P<0.05）。与miR-NC组相比,miR-509-5p组细胞的增殖、迁移和侵袭能力均明显减弱（P<0.05）,TWIST1和β-catenin蛋白的表达明显降低（P<0.05）,而AXIN1蛋白的表达明显升高（P<0.05）;野生型miR-509-5p组细胞的荧光素酶活性明显低于miR-NC组（P<0.05）,而野生型anti-miR-509-5p组细胞的荧光素酶活性明显明显高于anti-miR-NC组（P<0.05）;miR-509-5p过表达可抑制HMGA2表达,反之则促进其表达。沉默HMGA2表达后,H1299细胞的变化趋势与miR-509-5p过表达的结果相一致。结论:miR-509-5p可通过靶向HMGA2调控非小细胞肺癌H1299细胞的增殖、迁移和侵袭,其作用机制可能与抑制Wnt/β-catenin信号通路有关。     

The High Mobility Group A proteins contribute to thyroid cell transformation by regulating miR-603 and miR-10b expression

The overexpression of the HMGA1 proteins is a feature of human malignant neoplasias and has a causal role in cell transformation. The aim of our study has been to investigate the microRNAs (miRNAs or miRs) regulated by the HMGA1 proteins in the process of cell transformation analyzing the miRNA expression profile of v-ras-Ki oncogene-transformed thyroid cells expressing or not HMGA1 proteins. We demonstrate that, among the miRNAs regulated by cell transformation, there are miR-10b, miR-21, miR-125b, miR-221 and miR-222 that are positively and miR-34a and miR-603 that are negatively regulated by HMGA1 expression. Then, we focused our attention on the miR-10b and miR-603 whose expression was dependent on the presence of HMGA1 also in other cell systems. We found that miR-10b is able to target the PTEN gene, whereas miR-603 targets the CCND1 and CCND2 genes coding for the cyclin D1 and cyclin D2 proteins, respectively. Moreover, functional studies showed that miR-10b and miR-603 regulate positively and negatively, respectively, cell proliferation and migration suggesting a role of their dysregulation in thyroid cell transformation.