miR-150 and SRPK1 regulate AKT3 expression to participate in LPS-induced inflammatory response

miR-150 was found to target the 3′-untranslated regions of AKT3, and the AKT pathway was affected by SR protein kinase 1 (SRPK1). However, the expression and significance of miR-150, AKT3 and SRPK1 in acute lung injury (ALI) were not clear. Here, we found that the expression of miR-150 was significantly reduced, while the expression of AKT3 and SRPK1 were markedly increased in LPS-treated A549, THP-1 and RAW 264.7 cells. miR-150 significantly decreased levels of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α, reduced the expression of AKT3, but had no impact on SRPK1 expression compared with the control group in LPS-treated A549, THP-1 and RAW 264.7 cells. AKT3 silencing only reduced the production of pro-inflammatory cytokines and showed no effect on miR-150 and SRPK1 expression. Finally, we observed that miR-150 mimics and/or silencing of SRPK1 decreased the expression of AKT3 mRNA. Besides, over-expression of miR-150 or silencing of SRPK1 also reduced the expression of AKT3 protein, which exhibited the lowest level in the miR-150 mimics plus si-SRPK1 group. However, si-SRPK1 had no effect on miR-150 level. In conclusion, miR-150 and SRPK1 separately and cooperatively participate into inflammatory responses in ALI through regulating AKT3 pathway. Increased miR-150 and silenced SRPK1 may be a novel potential factor for preventing and treating more inflammatory lung diseases.     

miR-150-5p Inhibits Hepatoma Cell Migration and Invasion by Targeting MMP14

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality worldwide. Despite progress in diagnostics and treatment of HCC, its prognosis remains poor because the molecular mechanisms underlying hepatocarcinogenesis are not well understood. In the study, we focused on identifying the role of miRNAs in HCC progression. miRNA microarray was used to analyze the differentially expressed miRNAs, and the results were validated by qPCR. We found that the miR-150-5p expression is down-regulated in HCC tissues compared with pair non-tumor tissues. miR-150-5p expression is also decreased in metastatic cancer tissues compared with pair primary tissues, indicating that miR-150-5p may be involved in HCC metastasis. Functionally, miR-150-5p inhibition significantly promotes hepatoma cell migration and invasion, whereas miR-150-5p overexpression suppresses cancer cell migration and invasion in vitro. The matrix metalloproteinase 14 (MMP14) is identified as a new target gene of miR-150-5p. miR-150-5p markedly inhibits MMP14 expression in hepatoma cells, and miR-150-5p expression is negative correlation with MMP14 expression in vivo. More important, re-expression of MMP14 in hepatoma cells partially reverses the effect of miR-150-5p in inhibiting cell invasion.     

miR-150-504-519d inhibits the growth of human colorectal cancer cell line SW48 and downregulates c-FLIP receptor

microRNAs (miRNAs) are noncoding RNAs that regulates the expression of target messenger RNAs (mRNAs). c-FLIP is an inhibitor of cell apoptosis through inhibition of caspase 8. miR-150, miR-504, and miR-519d were related to cancer cell proliferation, invasion, and migration in colorectal cancer (CRC). However, the role of miR-150-504-519d in CRC has not been studied and the relationship between miR-150-504-519d and c-FLIP remains unclear. In this study, we found that c-FLIP was upregulated in CRC tissues, without detectable expression in normal CRC tissues. Using SW48 cell line, we further showed that miR-150-504-519d inhibited migration, invasion, and promoted apoptosis of SW48 cells. Moreover, in SW48 cell line transfected with miR-150-504-519d, the protein expression of c-FLIP was significantly lower compared with cells transfected with scramble. Our results demonstrated upregulation of c-FLIP in CRC, which was downregulated in SW48 cells after the transfection of miR-150-504-519d, suggesting that manipulation of miR-150-504-519d expression might be a novel approach for the treatment of colorectal cancer.     

miR-146a and miR-150 promote the differentiation of CD133+ cells into T-lymphoid lineage

MicroRNAs control the genes involved in hematopoietic stem cell (HSCs) survival, proliferation and differentiation. The over-expression of miR-146 and miR-150 has been reported during differentiation of HSCs into T-lymphoid lineage. Therefore, in this study we evaluated the effect of their over-expression on CD133⁺ cells differentiation to T cells. miR-146a and miR-150 were separately and jointly transduced to human cord blood derived CD133⁺ cells (>97 % purity). We used qRT-PCR to assess the expression of CD2, CD3ε, CD4, CD8, CD25, T cell receptor alpha (TCR-α) and Ikaros genes in differentiated cells 4 and 8 days after transduction of the miRNAs. Following the over-expression of miR-146a, significant up-regulation of CD2, CD4, CD25 and Ikaros genes were observed (P < 0.01). On the other hand, over-expression of miR-150 caused an increase in the expression of Ikaros, CD4, CD25 and TCR-α. To evaluate the combinatorial effect of miR-146a and miR-150, transduction of both miRNAs was concurrently performed which led to increase in the expression of Ikaros, CD4 and CD3 genes. In conclusion, it seems that the effect of miR-150 and miR-146a on the promotion of T cell differentiation is time-dependant. Moreover, miRNAs could be used either as substitutes or complements of the conventional differentiation protocols for higher efficiency.     

miR-223 regulates migration and invasion by targeting Artemin in human esophageal carcinoma

Background

Artemin (ARTN) is a neurotrophic factor belonging to the glial cell-derived neurotrophic factor family of ligands. To develop potential therapy targeting ARTN, we studied the roles of miR-223 in the migration and invasion of human esophageal carcinoma.

Methods

ARTN expression levels were detected in esophageal carcinoma cell lines KYSE-150, KYSE-510, EC-9706, TE13, esophageal cancer tissues and paired non-cancerous tissues by Western blot. Artemin siRNA expression vectors were constructed to knockdown of artemin expression mitigated migration and invasiveness in KYSE150 cells. Monolayer wound healing assay and Transwell invasion assay were applied to observe cancer cell migration and invasion. The relative levels of expression were quantified by real-time quantitative PCR.

Results

ARTN expression levels were higher in esophageal carcinoma tissue than in the adjacent tissue and was differentially expressed in various esophageal carcinoma cell lines. ARTN mRNA contains a binding site for miR-223 in the 3'UTR. Co-transfection of a mir-223 expression vector with pMIR-ARTN led to the reduced activity of luciferase in a dual-luciferase reporter gene assay, suggesting that ARTN is a target gene of miR-223. Overexpression of miR-223 decreased expression of ARTN in KYSE150 cells while silencing miR-223 increased expression of ARTN in EC9706 cells. Furthermore, overexpression of miR-223 in KYSE150 cells decreased cell migration and invasion. Silencing of miR-223 in EC9706 cells increased cell migration and invasiveness.

Conclusions

These results reveal that ARTN, a known tumor metastasis-related gene, is a direct target of miR-223 and that miR-223 may have a tumor suppressor function in esophageal carcinoma and could be used in anticancer therapies.     

c-Myb Inhibits Myoblast Fusion

Satellite cells represent a heterogeneous population of stem and progenitor cells responsible for muscle growth, repair and regeneration. We investigated whether c-Myb could play a role in satellite cell biology because our previous results using satellite cell-derived mouse myoblast cell line C2C12 showed that c-Myb was expressed in growing cells and downregulated during differentiation. We detected c-Myb expression in activated satellite cells of regenerating muscle. c-Myb was also discovered in activated satellite cells associated with isolated viable myofiber and in descendants of activated satellite cells, proliferating myoblasts. However, no c-Myb expression was detected in multinucleated myotubes originated from fusing myoblasts. The constitutive expression of c-Myb lacking the 3′ untranslated region (3′ UTR) strongly inhibited the ability of myoblasts to fuse. The inhibition was dependent on intact c-Myb transactivation domain as myoblasts expressing mutated c-Myb in transactivation domain were able to fuse. The absence of 3′ UTR of c-Myb was also important because the expression of c-Myb coding region with its 3′ UTR did not inhibit myoblast fusion. The same results were repeated in C2C12 cells as well. Moreover, it was documented that 3′ UTR of c-Myb was responsible for downregulation of c-Myb protein levels in differentiating C2C12 cells. DNA microarray analysis of C2C12 cells revealed that the expression of several muscle-specific genes was downregulated during differentiation of c-Myb-expressing cells, namely: ACTN2, MYH8, TNNC2, MYOG, CKM and LRRN1. A detailed qRT-PCR analysis of MYOG, TNNC2 and LRRN1 is presented. Our findings thus indicate that c-Myb is involved in regulating the differentiation program of myogenic progenitor cells as its expression blocks myoblast fusion.     

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.     

MicroRNA miR-150 is involved in Vα14 invariant NKT cell development and function

CD1d-restricted Vα14 invariant NKT (iNKT) cells play an important role in the regulation of diverse immune responses. MicroRNA-mediated RNA interference is emerging as a crucial regulatory mechanism in the control of iNKT cell differentiation and function. Yet, roles of specific microRNAs in the development and function of iNKT cells remain to be further addressed. In this study, we identified the gradually increased expression of microRNA-150 (miR-150) during the maturation of iNKT cells in thymus. Using miR-150 knockout (KO) mice, we found that miR-150 deletion resulted in an interruption of iNKT cell final maturation in both thymus and periphery. Upon activation, iNKT cells from miR-150KO mice showed significantly increased IFN-γ production compared with wild-type iNKT cells. Bone marrow-transferring experiments demonstrated the cell-intrinsic characteristics of iNKT cell maturation and functional defects in mice lacking miR-150. Furthermore, miR-150 target c-Myb was significantly upregulated in miR-150KO iNKT cells, which potentially contribute to iNKT cell defects in miR-150KO mice. Our data define a specific role of miR-150 in the development and function of iNKT cells.     

Tubular cell-derived exosomal miR-150-5p contributes to renal fibrosis following unilateral ischemia-reperfusion injury by activating fibroblast in vitro and in vivo

Unilateral ischemia reperfusion injury (UIRI) with longer ischemia time is associated with an increased risk of acute renal injury and chronic kidney disease. Exosomes can transport lipid, protein, mRNA, and miRNA to corresponding target cells and mediate intercellular information exchange. In this study, we aimed to investigate whether exosome-derived miRNA mediates epithelial-mesenchymal cell communication relevant to renal fibrosis after UIRI. The secretion of exosomes increased remarkably in the kidney after UIRI and in rat renal tubular epithelium cells (NRK-52E) after hypoxia treatment. The inhibition of exosome secretion by Rab27a knockout or GW4869 treatment ameliorates renal fibrosis following UIRI in vivo. Purified exosomes from NRK-52E cells after hypoxia treatment could activate rat kidney fibroblasts (NRK-49F). The inhibition of exosome secretion in hypoxic NRK-52E cells through Rab27a knockdown or GW4869 treatment abolished NRK-49F cell activation. Interestingly, exosomal miRNA array analysis revealed that miR-150-5p expression was increased after hypoxia compared with the control group. The inhibition of exosomal miR-150-5p abolished the ability of hypoxic NRK-52E cells to promote NRK-49F cell activation in vitro, injections of miR-150-5p enriched exosomes from hypoxic NRK-52E cells aggravated renal fibrosis following UIRI, and renal fibrosis after UIRI was alleviated by miR-150-5p-deficient exosome in vivo. Furthermore, tubular cell-derived exosomal miR-150-5p could negatively regulate the expression of suppressor of cytokine signaling 1 to activate fibroblast. Thus, our results suggest that the blockade of exosomal miR-150-5p mediated tubular epithelial cell-fibroblast communication may provide a novel therapeutic target to prevents UIRI progression to renal fibrosis.     

MiR-150-5p通过靶向调控Rab1A抑制乳腺癌细胞MDA-231的上皮-间质转化

先前的研究表明,miR-150-5p发挥抑癌基因的作用,调控肿瘤细胞的侵袭与转移。然而,关于其在乳腺癌细胞侵袭与转移中的机制尚不明确。本实验旨在研究miR-150-5p负向调控Rab1A在乳腺癌细胞上皮-间质转化（epithelial-mesenchymal transition,EMT）中的作用。双荧光素酶的结果显示,miR-150-5p可负向调控Rab1A。荧光定量PCR (qRT-PCR) 结果显示,miR-150-5p在乳腺癌细胞MCF-7及MDA-MB-231（MDA-231）中的表达水平明显低于正常乳腺上皮细胞MCF-10A; 在MDA-231中过表达miR-150-5p后,qRT-PCR结果显示,Rab1A mRNA的表达水平明显降低。Western印迹结果显示,过表达miR-150-5p后,miR-150-5p组细胞中的Rab1A、波形蛋白(vimentin)及N-钙黏着蛋白(N-cadherin)的表达水平相对于对照组（NC）细胞明显降低,而E-钙黏着蛋白(E-cadherin)的表达水平明显增加。Transwell侵袭和划痕实验显示,与miR-150-5p+Con组细胞相比,miR-150-5p+Rab1A组细胞的侵袭和迁移能力明显增加。qRT-PCR结果显示,miR-150-5p+Rab1A组细胞的Rab1A mRNA表达水平明显增加。Western印迹结果显示,miR-150-5p+Rab1A组细胞中的波形蛋白、N-钙黏着蛋白表达水平明显增加, 而E-钙黏着蛋白表达明显降低,过表达Rab1A后显著逆转了miR-150-5p对EMT的影响。综上所述,miR-150-5p可以通过负向调控Rab1A抑制EMT,进而抑制乳腺癌细胞的侵袭和迁移。     

miR-181a post-transcriptionally downregulates oncogenic RalA and contributes to growth inhibition and apoptosis in chronic myelogenous leukemia (CML)

MicroRNAs (miRNAs) are a class of short RNAs that regulate gene expression through either translational repression or mRNA cleavage. miRNA-181a (miR-181a), one of the many miRNAs conserved among vertebrates, is differentially expressed in a variety of leukemia. However, its function in leukemia, particularly chronic myelogenous leukemia (CML), is poorly understood. Here we have reported the identification of miR-181a targets by combining TargetScan software prediction and expression profiling through overexpression of miR-181a mimic in leukemic K562 cells. Four overlapping genes were found to be the likely targets of miR-181a. Among the four genes, RalA is a downstream molecule of bcr-abl fusion protein in ras signaling pathway. However, its role in CML remains elusive. Luciferase reporter and Western blot assays confirmed that RalA is a direct target of miR-181a. overexpression of miR-181a effectively suppresses cell growth and induces G2-phase arrest and apoptosis partially by targeting RalA in leukemic K562 cells. Using the KEGG database combined with recent publications, downstream signaling pathway of RalA was graphed by cytoscape software. Therefore, our study is the first to report that RalA is directly regulated by miR-181a and plays an important role in CML. The approach of computational prediction combined with expression profiling might be valuable for the identification of miRNA targets in animal.     

Brain-derived neurotrophic factor expression is repressed during myogenic differentiation by miR-206

Brain-derived neurotrophic factor (BDNF) is required for efficient skeletal-muscle regeneration and perturbing its expression causes abnormalities in the proliferation and differentiation of skeletal muscle cells. In this study, we investigated the mechanism of BDNF suppression that occurs during myogenic differentiation. BDNF is expressed at the mRNA level as two isoforms that differ in the length of their 3'UTRs as a result of alternative cleavage and polyadenylation. Sequence analysis revealed the presence of three miR-206 target sites in the long BDNF 3'UTR (BDNF-L), whereas only one site was found in the short mRNA BDNF 3'UTR (BDNF-S). miR-206 is known to regulate the differentiation of C2C12 myoblasts and its expression is induced during the transition from myoblasts to myotubes. We thus examined whether miR-206-mediated suppression is responsible for the expression pattern of BDNF during myogenic differentiation. BDNF-L was suppressed to a greater extent than BDNF-S during differentiation of C2C12 myoblasts. Transfection of a miR-206 precursor decreased activity of reporters representative of the BDNF-L 3'UTR, but not BDNF-S 3'UTR, and repressed endogenous BDNF mRNA levels. This suppression was found to be dependent on the presence of multiple miR-206 target sites in the BDNF-L 3'UTR. Conversely, suppression of miR-206 levels resulted in de-repression of BDNF 3'UTR reporter activity and increased endogenous BDNF-L mRNA levels. A receptor for BDNF, p75(NTR) , was also suppressed during differentiation and in response to miR-206, but this appeared to not be entirely mediated via a miR-206 target site its 3'UTR. Based on these observations, BDNF represents a novel target through which miR-206 controls the initiation and maintenance of the differentiated state of muscle cells. These results further suggest that miR-206 might play a role in regulating retrograde signaling of BDNF at the neuromuscular junction.