lncRNA MEG3 modified epithelial-mesenchymal transition of ovarian cancer cells by sponging miR-219a-5p and regulating EGFR

This study was aimed to verify whether there existed any associations between long noncoding RNA MEG3/miR-219a-5p/EGFR axis and the development of ovarian cancer (OC). As a whole, we gathered 317 pairs of OC tissues and surgical marginal normal tissues and simultaneously acquired four OC cell lines (ie, A2780, Caov-3, OVCAR-3, and SKOV-3) and human normal ovarian surface epithelial cell line. Moreover, pcDNA3.1-MEG3, si-MEG3, miR-219a-5p mimic, miR-219a-5p inhibitor, pcDNA3.1-EGFR, and si-EGFR were, respectively, transfected into the OC cells, and their impacts on viability, proliferation, apoptosis, invasion, and migration of OC cells were assessed via conduction of MTT assay, colony formation assay, flow cytometry assay, transwell assay, and scratch assay. Ultimately, dual-luciferase reporter gene assay was performed to testify the targeted relationships among maternally expressed gene 3 (MEG3), miR-219a-5p, and estimated glomerular filtration rate (EGFR). It was indicated that underexpressed MEG3 and miR-219a-5p were significantly associated with unfavorable prognosis of patients with OC when compared with overexpressed MEG3 and miR-219a-5p (P < .05). In addition, the OC cells transfected with si-MEG3 or miR-219a-5p inhibitor exhibited stronger viability, proliferation, invasion, and migration than untreated cells (P < .05). Correspondingly, the apoptotic percentage of OC cells was reduced observably under treatments of si-MEG3 and miR-219a-5p inhibitor (P < .05). Moreover, MEG3 exerted modulatory effects on the expression of miR-219a-5p (P < .05), and there was a sponging relationship between them (P < .05). Finally, EGFR expression was modified by both MEG3 and miR-219a-5p significantly (P < .05), and raising EGFR expression could changeover the impacts of MEG3 and miR-219a-5p on the above-mentioned activity of OC cells (P < .05). Conclusively, MEG3 could serve as a promising biomarker for diagnosis and treatment of OC, considering its involvement with OC etiology via regulation of miR-219a-5p/EGFR axis.     

MicroRNA-188-5p promotes apoptosis and inhibits cell proliferation of breast cancer cells via the MAPK signaling pathway by targeting Rap2c

Breast cancer is a common malignancy that is highly lethal with poor survival rates and immature therapeutics that urgently needs more effective and efficient therapies. MicroRNAs are intrinsically involved in different cancer remedies, but their mechanism in breast cancer has not been elucidated for prospective treatment. The function and mechanism of microRNA-188-5p (miR-188) have not been thoroughly investigated in breast cancer. In our study, we found that the expression of miR-188 in breast cancer tissues was obviously reduced. Our findings also revealed the abnormal overexpression of miR-188 in 4T1 and MCF-7 cells significantly suppressed cell proliferation and migration and also enhanced apoptosis. miR-188 induced cell cycle arrest in the G1 phase. To illuminate the molecular mechanism of miR-188, Rap2c was screened as a single target gene by bioinformatics database analysis and was further confirmed by dual-luciferase assay. Moreover, Rap2c was found to be a vital molecular switch for the mitogen-activated protein kinase signaling pathway in tumor progression by decreasing apoptosis and promoting proliferation and migration. In conclusion, our results revealed that miR-188 is a cancer progression suppressor and a promising future target for breast cancer therapy.     

乙型肝炎病毒x蛋白通过靶向miR-200c诱导DNA异常甲基化

乙型肝炎病毒x (hepatitis B virus x,HBx)蛋白是导致肝癌(hepatocellular Carcinoma,HCC)的重要因素.但HBX在HCC形成过程中表观遗传机制尚有待阐明.本研究发现microRNA-200c (miR-200c)在过表达乙型肝炎病毒的HCC中下调,并且其直接靶向DNA甲基转移酶3A (DNA methyltransferase 3A,DNMT3A).此外,miR-200c和DNMT3A在HB诱发的肝癌组织中呈现负相关.乙型肝炎病毒诱导miR-200c下调,进而引起DNMT3A表达上调,导致细胞中肿瘤相关基因的启动子超甲基化.我们对乙型肝炎病毒诱导的肝癌表观遗传学改变进行了进一步研究,并提出一种基于miRNA的靶向治疗乙型肝炎病毒相关肝癌的潜在方法.     

miR-144 suppresses cell proliferation and migration in colorectal cancer by targeting NRAS

Colorectal cancer (CRC) is a type of malignant cancer that has become particularly prevalent worldwide. It is of crucial importance to CRC treatment that the underlying molecular mechanism of CRC progression is determined. The NRAS gene is an important small G protein that is involved in various biological processes, including cancers. NRAS is an oncogene in many neoplasms but its function and regulation in CRC have seldom been investigated. In this study, it was uncovered that the NRAS protein was significantly upregulated in CRC tissues. According to a bioinformatics prediction, we identified that miR-144 may target NRAS to suppress its expression. In vitro experiments indicated that miR-144 decreased NRAS expression in different CRC cell lines (SW480, LoVo, and Caco2). By inhibiting NRAS, miR-144 repress SW480 cell proliferation and migration. Moreover, miR-144 decelerated the growth of SW480 xenograft tumors in vivo by targeting NRAS. In summary, our results identified a novel miR-144-NRAS axis in CRC that could promote the research and treatment of CRC.     

miR-148a promoted cell proliferation by targeting p27 in gastric cancer cells

Accumulating evidence has shown that miRNAs are aberrantly expressed in human gastric cancer and crucial to tumorigenesis. Herein, we identified the role of miR-148a in gastric cell proliferation. miR-148a knockdown inhibited cell proliferation in gastric cancer cell lines. Conversely, miR-148a overexpression promoted cell proliferation and cell cycle progression. p27, a key inhibitor of cell cycle, was verified as the target of miR-148a, indicating miR-148a might downregulate p27 expression to promote gastric cell proliferation. Moreover, we confirmed that miR-148a expression was frequently and dramatically downregulated in human advanced gastric cancer tissues, and observed a good inverse correlation between miR-148a and p27 expression in tumor samples. Thus, our results demonstrated that miR-148a downregulation might exert some sort of antagonistic function in cell proliferation, rather than promote cell proliferation in gastric cancer.     

miR-362靶向ZNF644基因调控猪未成熟支持细胞的增殖和凋亡

睾丸组织中未成熟支持细胞的增殖能力决定成熟支持细胞的数量,进而制约成年雄性动物的精子生成能力。研究表明microRNA (miRNA)参与调控猪未成熟支持细胞的增殖和凋亡,但大部分鉴定出的miRNA功能仍不明确。本文基于前期RNA-seq数据筛选结果,研究了miR-362对猪未成熟支持细胞增殖和凋亡的调控作用。首先利用生物信息学方法预测miR-362的靶基因,通过qRT-PCR技术检测miR-362和ZNF644基因在不同发育阶段的猪睾丸组织中的表达水平以及在猪未成熟支持细胞中过表达或抑制表达miR-362后ZNF644基因的表达水平,采用双荧光素酶报告基因系统验证miR-362与ZNF644基因之间的靶向关系。结果显示,miR-362与ZNF644基因3′UTR具有一个潜在的结合位点,miR-362和ZNF644基因在猪睾丸组织中的mRNA表达水平显著负相关(r=-0.723, P<0.01),miR-362和psiCHECK2-ZNF644-WT 3′UTR共转染组的双荧光活性显著降低,且miR-362显著调节ZNF644基因的表达水平,表明miR-362靶向ZNF644基因并抑制其表达水平。为进一步检测过表达miR-362或抑制表达ZNF644基因对猪未成熟支持细胞增殖和凋亡的影响,通过流式细胞术检测细胞周期,CCK8和EdU试剂盒检测细胞增殖情况,Annexin V-FITC/PI方法和qRT-PCR技术检测细胞凋亡情况及凋亡相关基因的表达水平。结果表明,过表达miR-362后,猪未成熟支持细胞周期被阻滞在G₁期,抑制表达ZNF644基因后,猪未成熟支持细胞被阻滞在G₂期,细胞增殖能力显著减弱,细胞凋亡率显著提高,细胞凋亡相关基因呈促进凋亡的差异表达。本研究结果证实miR-362靶向ZNF644基因抑制猪未成熟支持细胞的增殖而促进其凋亡,为深入研究miR-362在猪精子生成过程中的生物学功能提供了理论基础。     

MicroRNA-384 regulates cell proliferation and apoptosis through directly targeting WISP1 in laryngeal cancer

Laryngeal cancer (LC) is an increasingly common malignant tumors of head and neck cancer. Aberrant expression of microRNA (miRNA) is closely related with LC development. In the current study, we investigated the biological function and underlying molecular mechanism of miR-384 in LC. The results showed that the miR-384 expression was markedly downregulated in LC tissue and cell lines (TU212 and TU686) as compared with that of adjacent nontumor tissues and a normal human bronchial epithelial cell line. Next, we performed gain-of-function and loss-of-function experiments in the TU212 and TU686 cells by transfecting the cells with miR-384 mimics, miR-384 inhibitor, or miRNA control. Moreover, results showed that miR-384 mimic remarkably inhibited LC cell proliferation, which was notably decreased by miR-384 inhibitor. Furthermore, miR-384 mimics notably increased the amounts of DNA fragmentation from the apoptotic cells (a hallmark of apoptosis) and the caspase-3 activity, whereas miR-384 inhibitor resulted in a decline of DNA fragmentation and the caspase-3 activity compared with its control. In addition, a dual-luciferase reporter assay confirmed that Wnt-induced secreted protein-1 (WISP1) gene was a direct target of miR-384. MiR-384 mimic remarkably inhibited the messenger RNA and protein expression of WISP1, which was upregulated by miR-384 inhibitor as compared to its control. WISP1 knockdown by small interfering RNA inhibited LC cell proliferation and promoted cell apoptosis. WISP1 overexpression partly abrogates the effect of miR-384 overexpression. Taken together, these data indicate that miR-384 regulates LC cell proliferation and apoptosis through targeting WISP1 signaling pathway, providing a novel insight into the LC treatment.     

Mir-335-5p靶向G6PD对结肠癌细胞增殖、凋亡的影响

目的:探讨Mir-335-5p通过靶向G6PD对结肠癌细胞增殖、凋亡的影响.方法:设置正常结肠细胞组、空白对照组、NC组、miRNA-335-5p mimic组;体外培养结肠上皮细胞(IEC)和人源性结肠癌细胞SW480,并对NC组、miRNA-335-5p mimic组细胞进行转染;采用RT-qPCR检测各组细胞中m...     

SOX-17 is involved in invasion and apoptosis of colorectal cancer cells through regulating miR-302b-3p expression

The prognosis of advanced colorectal cancer (CRC) is currently still very poor, which suggests that the biological mechanisms of CRC oncogenesis are not fully understood. This study was conducted to explore the regulatory effect of SOX-17 on the expression of microRNA (miR)-302b-3p, and the involvement of SOX-17 in the invasion and apoptosis of CRC cells. The expression of SOX-17 and miR-302a,b,c,d-3p in colorectal cancer and normal colon epithelial cell lines was measured by real-time polymerase chain reaction and/or western blot. The regulatory effects of SOX-17 on miR-302b-3p gene in HT29 and LoVo cells were tested using the ChiP assay. The biological activities of SOX-17 and miR-302b-3p were evaluated by invasion and apoptosis assay. Results showed that transfection of SOX-17 small interfering RNA (siSOX-17) significantly increased, whereas transfection of SOX-17 overexpression vector (oeSOX-17) significantly decreased, miR-302b expression in HT29 and LoVo cells. Cotransfection of oeSOX-17 and miR-302b-3p inhibitor (INmiR-302b) significantly blocked the effects of SOX-17 in HT29 and LoVo cells. ChIP experiments showed that SOX-17 bonded to the miR-302b-3p promoter in HT29 and LoVo cells. Transfection of oeSOX-17 and miR-302b-3p mimics (MImiR-302b) significantly decreased, whereas transfection of siSOX-17 and INmiR-302b significantly increased, the invasion of HT29 and LoVo cells. In contrast, transfection of oeSOX-17 and MImiR-302b significantly increased, while transfection of siSOX-17 and INmiR-302b significantly decreased, apoptosis in HT29 and LoVo cells. Cotransfection of oeSOX-17 and INmiR-302b significantly blocked the effects of oeSOX-17 on cell invasion and apoptosis in HT29 and LoVo cells. These results suggested that SOX-17 can bind to the promoter of miR-302b-3p gene to regulate its expression, while both SOX-17 and miR-302b regulate the invasion and apoptosis in colorectal cancer cells.     

miR-548c-5p inhibits colorectal cancer cell proliferation by targeting PGK1

Accumulating studies have implicated that microRNAs (miRNAs) are involved in the pathogenesis of colorectal cancer (CRC). However, the role of miR-548c-5p, a novel identified miRNA in malignancies, in colorectal carcinogenesis remains largely unknown. The present study is aimed to investigate the effect and molecular mechanism of miR-548c-5p in CRC by a sequence of cellular experiments. miR-548c-5p was significantly downregulated, whereas phosphoglycerate kinase 1 (PGK1), a key enzyme for glycolysis, was obviously upregulated in peripheral blood mononuclear cells and cancer tissues from patients with CRC. Besides, miR-548c-5p and PGK1 were negatively associated with each other. The luciferase reporter assay revealed that PGK1 was a targeted gene of miR-548c-5p. Moreover, the proliferation and generation of inflammatory cytokines (TNF-α and IL-6) were significantly inhibited in miR-548c-5p-overexpressed SW480 CRC cells stimulated by lipopolysaccharide (LPS). Accordingly, miR-548c-5p may serve as a cancer suppressor in CRC by targeting PGK1.     

Fluid shear stress regulates osteoblast proliferation and apoptosis via the lncRNA TUG1/miR-34a/FGFR1 axis

LncRNAs and microRNAs play critical roles in osteoblast differentiation and bone formation. However, their exact roles in osteoblasts under fluid shear stress (FSS) and the possible mechanisms remain unclear. The aim of this study was to explore whether and how miR-34a regulates osteoblast proliferation and apoptosis under FSS. In this study, FSS down-regulated miR-34a levels of MC3T3-E1 cells. MiR-34a up-regulation attenuated FSS-induced promotion of proliferation and suppression of apoptosis. Luciferase reporter assay revealed that miR-34a directly targeted FGFR1. Moreover, miR-34a regulated osteoblast proliferation and apoptosis via FGFR1. Further, we validated that lncRNA TUG1 acted as a competing endogenous RNA (ceRNA) to interact with miR-34a and up-regulate FGFR1 protein expression. Furthermore, lncRNA TUG1 could promote proliferation and inhibit apoptosis. Taken together, our study revealed the key role of the lncRNA TUG1/miR-34a/FGFR1 axis in FSS-regulated osteoblast proliferation and apoptosis and may provide potential therapeutic targets for osteoporosis.     

Retracted: miR-150 might inhibit cell proliferation and promote cell apoptosis by targeting LMO4 in Burkitt lymphoma

This study aimed at investigating the effect of microRNA-150 (miR-150) on cell proliferation of Burkitt lymphoma and its molecular mechanism. Gene expression analysis was applied to identify target genes of miR-150 in Burkitt lymphoma cell line ST486 based on the dataset from the Gene Expression Omnibus (GEO) datasets GSE86432. miRNA mimics, inhibitor and small interfering RNA (siRNA) were fluorescently labeled by Cy3, whereas plasmid vector was labeled by EGFP. Cells were viewed by fluorescence microscope and transfection efficiency was evaluated through fluorescent cell percentage. Quantitative real-time polymerase chain reaction analysis (qRT-PCR) and western blot were applied to detect the expression level of miR-150 and LMO4. Cell proliferation, cell cycle, and apoptosis were explored by CCK-8, flow cytometry. Targeting relationship was validated by the Luciferase reporter assay. Tumor xenograft and immunohistochemical analysis were conducted in nude mice model. In Burkitt lymphoma cells, miR-150 expression was significantly lower than normal ones, whereas the expression of LMO4 was upregulated. miR-150 might inhibit cell proliferation and promoted apoptosis in Burkitt lymphoma deterioration by downregulating LMO4. The results of tumor xenograft further confirmed the role of miR-150 in Burkitt lymphoma. Targeting LMO4 is a significant mechanism by which miR-150 suppresses cell growth and promotes apoptosis in Burkitt lymphoma cells, thus may provide a novel target for Burkitt lymphoma therapy in the future.     

miR-146a interacting with lncRNA EPB41L4A-AS1 and lncRNA SNHG7 inhibits proliferation of bone marrow-derived mesenchymal stem cells

Emerging evidence suggests that microRNA plays a pivotal role in cell proliferation. Our previous research has certified that miR-146a attenuates osteoarthritis through the regulation of cartilage homeostasis. However, little information about the function of miR-146a in bone marrow-derived mesenchymal stem cells (BMSCs) proliferation and the underlying mechanism was available. Therefore, this study aims at investigating the role of miR-146a on the proliferation of BMSCs and the possible mechanisms involved. The function of miR-146a on BMSCs proliferation was studied through overexpression and knockdown of miR-146a or the indicated long noncoding RNAs (lncRNAs) in BMSCs and then the proliferation rate of the BMSCs were detected by Cell Counting Kit-8 assay, colony formation assay. Besides, flow cytometry was used to test the cell cycle state of BMSCs modified by overexpression or knockdown of miR-146a or lncRNA EPB41L4A-AS1 (EPB41L4A Antisense RNA 1) and small nucleolar RNA host gene 7 (SNHG7). The expression level of marker genes involved in modulating cell proliferation was evaluated by quantitative polymerase chain reaction and western blot analysis. We discovered that the knockdown of miR-146a significantly promoted BMSCs proliferation. Moreover, miR-146a could bind to and inhibit endogenous expression of EPB41L4A-AS1 and SNHG7. Further study demonstrated that overexpression of EPB41L4A-AS1 and SNHG7 significantly enhanced proliferation of BMSCs. For the first time, we certified that miR-146a suppressed BMSCs proliferation, but EPB41L4A-AS1 and SNHG7 promoted BMSCs proliferation in the present study. Mechanistically, miR-146a significantly inhibited BMSCs proliferation partly through miR-146a/EPB41L4A-AS1 SNHG7/cell proliferation signaling pathway axis.     

Study on the role of gga-miRNA-200a in regulating cell differentiation and proliferation of chicken breast muscle by targeting Grb2

Growth factor receptor-bound protein 2 (Grb2) have been proved by a lot of studies playing a major role in cell proliferation and cell differentiation. However, the regulation of Grb2 expression by microRNAs (miRNAs) in chicken breast muscle still remains unknown. The expression profile of Grb2 was checked based on our previous RNA sequencing data and the Grb2 relative expression level in breast muscle of aged hens (55-week-old) was validated significantly higher than juvenile hens (20-week-old) using qRT-PCR. miRNAs that interact with Grb2 have been predicted in chicken and the relationship between the potential miRNA and Grb2 was verified using dual luciferase reporter assay in chicken DF1 cells. Dual-luciferase reporter assays results demonstrated that the expression of luciferase reporter gene linked with part sequence of the 3′UTR of chicken Grb2 gene was down-regulated by the overexpression of gga (Gallus Gallus)-miR-200a-3p in the DF1 cells, and the down-regulation behavior was abolished when the gga-miR-200a-3p binding site in 3′UTR of Grb2 was mutated, indicating that gga-miR-200a can suppress the expression level of its target gene Grb2. Therefore, we concluded that the significantly increased expression level of Grb2 in the breast muscle of aged chicken can (at least partly can) be explained by the decreased expression of miR-200a, which reduced the inhibitory effect on Grb2. Taken together, these findings suggest that gga-miR-200a can suppress the expression level of its target gene Grb2 and might be involved in the cell differentiation and proliferation of chicken breast muscle through binding with the 3’UTR of Grb2.