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Extracellular vesicles (EVs) derived from Mesenchymal Stromal Cells (MSCs) have shown promising therapeutic potential for multiple diseases, including intervertebral disc degeneration (IDD). Nevertheless, the limited production and unstable quality of EVs hindered the clinical application of EVs in IDD. Selenomethionine (Se-Met), the major form of organic selenium present in the cereal diet, showed various beneficial effects, including antioxidant, immunomodulatory and anti-apoptotic effects. In the current study, Se-Met was employed to treat MSCs to investigate whether Se-Met can facilitate the secretion of EVs by MSCs and optimize their therapeutic effects on IDD. On the one hand, Se-Met promoted the production of EVs by enhancing the autophagy activity of MSCs. On the other hand, Se-Met pretreated MSC-derived EVs (Se-EVs) exhibited an enhanced protective effects on alleviating nucleus pulposus cells (NPCs) senescence and attenuating IDD compared with EVs isolated from control MSCs (C-EVs) in vitro and in vivo. Moreover, we performed a miRNA microarray sequencing analysis on EVs to explore the potential mechanism of the protective effects of EVs. The result indicated that miR-125a-5p is markedly enriched in Se-EVs compared to C-EVs. Further in vitro and in vivo experiments revealed that knockdown of miR-125a-5p in Se-EVs (miR KD -Se-EVs) impeded the protective effects of Se-EVs, while overexpression of miR-125a-5p (miR OE -Se-EVs) boosted the protective effects. In conclusion, Se-Met facilitated the MSC-derived EVs production and increased miR-125a-5p delivery in Se-EVs, thereby improving the protective effects of MSC-derived EVs on alleviating NPCs senescence and attenuating IDD., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Circular RNA plays a critical role in cell proliferation, differentiation, and autophagy. However, the role and mechanism of circRNA in preeclampsia is yet to be clarified. The present study investigated the function and mechanism of circ-0002814 in preeclampsia., Methods: The expression level of circ-0002814, microRNA 210 (miR210), Notch receptor 1 (Notch1), or cytoplasmic polyadenylation element-binding protein 2 (CPEB2) was investigated by Reverse transcription Real-time Quantitative PCR (RT-qPCR). The level of Notch1, CPEB2, and FUS (FUS RNA-binding protein) proteins was detected by western blot. The localization of circ-0002814 and miR-210 was determined by FISH assay. Cell proliferation and invasion were detected by EdU and transwell assays, respectively. The interaction between circ-0002814 and FUS protein was detected by RNA pulldown assay, while that between circ-0002814 and miR-210 was detected by dual-luciferase reporter assay., Results: The expression of circ-0002814 was decreased in the placenta and plasma of patients with preeclampsia. The ectopic expression of circ-0002814 promoted the invasion and proliferation of HTR8 cells compared to the control group (p < 0.05). Silencing circ-0002814 suppressed the invasion and proliferation of JEG3 cells compared to the control group (p < 0.05). circ&#95;0002814-regulated Notch1 and CPEB2 by interaction with miR-210 and also regulated FUS/VEGF axis in HTR8 and JEG3 cells., Conclusion: A low expression of circ-0002814 was detected in the plasma and placental tissue in preeclampsia patients. circ-0002814 participated in the proliferation and invasion of HTR8 and JEG3 cells. Thus, circ-0002814 may be considered as a potential diagnostic marker and therapeutic target for preeclampsia., (© 2022 Japan Society of Obstetrics and Gynecology.)

Objective: The objective of this research is to determine the role of miR-34a-5p in the occurrence and development of HCC by targeting VEGFA., Methods: The expression of miR-34a-5p in HCC cell lines and tumour tissue was detected by qRT-PCR; the effect of miR-34a-5p on the invasive ability of HCC cells (SMMC7721 and MHCC97H) were detected by Transwell invasion assay; VEGFA is predicted as a potential target gene of miR-34a-5p by TargetScan, and validated with dual-luciferase reporter gene assay, qRT-PCR and western blot. VEGFA expression in HCC cell lines and tumour tissue was detected using qRT-PCR; the regulation and influence of miR-34a-5p and VEGFA on the proliferation, invasion, migration and the S-phase cell of HCC cells with different invasive abilities were detected by CCK8, Transwell assay, wound healing assay, and flow cytometry. The effect of miR-34a-5p on the growth of tumour was detected by constructing a xenograft model of nude mice with HCC., Results: It was found that the expression of miR-34a-5p in HCC cells and tumour tissue was significantly decreased. Up-regulating miR-34a-5p expression could reduce the invasion ability of HCC cells. MiR-34a-5p could inhibit the mRNA and protein expression level of VEGFA via combining with the 3'-UTR of VEGFA. VEGFA was highly expressed in HCC cells and tumour tissues. The miR-34a-5p inhibited the proliferation, invasion, migration and S-phase arrest of HCC cells, but this inhibition effect could be neutralised by VEGFA; miR-34a-5p exerted the inhibitory effect on HCC cell proliferation and tumour growth in the HCC xenograft model of nude mice., Conclusion: These results suggest that miR-34a-5p could inhibit the occurrence and development of HCC by targeting VEGFA.

Objective: To investigate the drug resistant related FOXO3/Bcl-6 signaling pathway in K562/G cell line and its related microRNA(miRNA) mechanisms., Methods: The drug resistance potency of imatinib on K562/G was detected by MTT assay. The expression of FOXO3 and Bcl-6 proteins in K562 and K562/G cells was detected by Western blot. Real-time PCR (RT-PCR) was used to detect the expression of FOXO3 and Bcl-6 mRNA. The miRNA expression profiling in K562 and K562/G cells was analyzed by microarray technique, and the miRNA targeted to FOXO/Bcl-6 signaling pathway was identified., Results: The expression of FOXO3 and Bcl-6 protein was significantly increased in K562/G cells as compared with that in K562 cells (P<0.01), the expression level of Bcl-6 mRNA showed no increase in K562/G cells. However, FOXO3 mRNA was up-regulated in K562/G cells (P<0.05). MiRNA microarray results showed that 109 miRNAs were expressed differentially in K562 and K562/G cells. The expression of 81 miRNAs were up-regulated while 28 miRNAs were down-regulated. Through reverse prediction by bioinformatics, miR-6718-5p, miR-5195-5p, miR-4711-3p, miR-4763-5p, miR-4664-5p and miR-3176 were related to FOXO/Bcl-6 signaling pathway., Conclusion: The FOXO3/Bcl-6 signaling pathway contributes to imatinib resistance in K562/G cell line, and the miRNA expression profiles showed significant differences between K562/G and K562 cells.

Nucleotide-binding domain and leucine-rich repeat (LRR)-containing family protein 3 (NLRP3) regulated the maturation of inflammation-related cytokines by forming NLRP3 inflammasome, which plays pivotal roles in sepsis pathogenesis. In this study, we evaluated the genetic association of NLRP3 polymorphisms with sepsis (640 patients and 769 controls) and characterized the impact of NLRP3 polymorphisms on NLRP3 expression and inflammatory responses. No significant differences were observed in genotype/allelic frequencies of NLRP3 29940G>C between sepsis cases and controls. The G allele was significantly overrepresented in patients with septic shock than those in sepsis subgroup, and the GC/GG genetypes were related to the 28-day mortality of sepsis. Lipopolysaccharide challenge to peripheral blood mononuclear cells showed a significant suppression of NLRP3 mRNA expression and release of IL-1β and TNF-α in CC compared with the GC/GG genotype category. Functional experiments with luciferase reporter vectors containing the NLRP3 3'-UTR with the 29940 G-to-C variation in HUVECs and THP-1 cells showed a potential suppressive effect of miR-146a on NLRP3 transcription in the presence of the C allele. Taken together, these results demonstrated that the 29940 G-to-C mutation within the NLRP3 3'-UTR was a gain-of-function alteration that caused the suppression of NLRP3 expression and downstream inflammatory cytokine production via binding with miR-146a, which ultimately protected patients against susceptibility to sepsis progression and poor clinical outcome.

Emerging studies have indicated that the dysregulation of microRNAs (miRNAs or miRs) plays a vital role in the development and metastasis of tumors. However, the role of miR‑93‑5p in esophageal carcinoma (EC) has not been extensively reported. The present study thus focused on the role of miR‑93‑5p and its downstream target in the occurrence and development of EC. Firstly, miRNA expression profiles associated with EC were accessed from the TCGA&#95;ESCA dataset and analyzed. Subsequently, the expression patterns of miR‑93‑5p and TGFβR2 were characterized in the human esophageal cell line, Het‑1A, and the human EC cell lines, TE‑1, Eca‑109 and EC9706, by RT‑qPCR and western blot analysis. WST‑1 assay, flow cytometry, Transwell assay, wound healing assay and bioinformatics analysis were used to explore their functions in EC cells. Finally, a dual‑luciferase reporter assay was employed to determine the targeted association between miR‑93‑5p and TGFβR2. The results revealed that the expression of miR‑93‑5p was markedly higher in EC cell lines compared with that in the normal cell line. The overexpression of miR‑93‑5p facilitated cell proliferation, migration and invasion, and inhibited cell apoptosis. Additionally, TGFβR2 was identified as a functional target of miR‑93‑5p in EC cells, as judged by a series of in vitro experiments. Furthermore, it was found that the simultaneous overexpression of miR‑93‑5p and TGFβR2 almost had no effect on the biological behaviors of EC cells. On the whole, the present study demonstrates that miR‑93‑5p promotes the proliferation, migration and invasion, and inhibits the apoptosis of EC cells by targeting TGFβR2.

Diabetes mellitus (DM) often causes vascular endothelial damage and alters vascular microRNA (miR) expression. miR-448-3p has been reported to be involved in the development of DM, but whether miR-448-3p regulates diabetic vascular endothelial dysfunction remains unclear. To investigate the molecular mechanism of diabetic vascular endothelial dysfunction and the role of miR-448-3p therein, Sprague-Dawley rats were injected with streptozotocin (STZ) to establish diabetic animal model and the rat aortic endothelial cells were treated with high glucose to establish diabetic cell model. For the treatment group, after the induction of diabetes, the miR-448-3p levels in vivo and in vitro were upregulated by adeno-associated virus serotype 2 (AAV2)-miR-448-3p injection and miR-448-3p mimic transfection, respectively. Our results showed that AAV2-miR-448-3p injection alleviated the body weight loss and blood glucose level elevation induced by STZ injection. The miR-448-3p level was significantly decreased and the dipeptidyl peptidase-4 (DPP-4) messenger RNA level was increased in diabetic animal and cell models, which was reversed by miR-448-3p treatment. Moreover, the diabetic rats exhibited endothelial damage and endothelial-mesenchymal transition (EndMT), while AAV2-miR-448-3p injection relieved those situations. In vitro experiments demonstrated that miR-448-3p overexpression in endothelial cells alleviated endothelial damage by inhibiting EndMT through blocking the transforming growth factor-β/Smad pathway. We further proved that miR-448-3p negatively regulated DPP-4 by binding to its 3'-untranslated region, and DPP-4 overexpression reversed the effect of miR-448-3p overexpression on EndMT. Overall, we conclude that miR-448-3p overexpression inhibits EndMT via targeting DPP-4 and further ameliorates diabetic vascular endothelial dysfunction, indicating that miR-448-3p may serve as a promising therapeutic target for diabetic endothelial dysfunction., (© 2020 Wiley Periodicals LLC.)

Accumulating evidence suggests that long noncoding RNA (lncRNA) small nucleolar RNA host gene 3 (SHNG3) plays crucial roles in the initiation and progression of various types of malignant cancers. Yet, the role played by SNHG3 in breast cancer as well as the associated mechanisms remain largely unclear. The expression of SNHG3 was detected in breast cancer tissues and cell lines by reverse‑transcription quantitative PCR (RT‑qPCR). Cell proliferation, colony formation, cell cycle distribution, migration and invasion abilities were detected by Cell Counting Kit‑8, colony formation assay, flow cytometry, wound‑healing and Matrigel invasion assays, respectively. The regulatory relationships between SNHG3 and miR‑326 were explored by luciferase reporter assay. A nude mouse model was established to investigate the effect of SNHG3 in vivo. The results showed an upregulation of SNHG3 in breast cancer tissues and cell lines. Loss‑of‑function assays revealed significant suppression of breast cancer behaviors such as: Abilities to proliferate, form colonies, migrate and invade in vitro coupled with a delayed growth of tumors in vivo when SNHG3 was knocked down. Mechanically, it was shown that SNHG3 served as a competing endogenous RNA (ceRNA) of miR‑326 that in turn is a tumor suppressor in this cancer. The correlation between the expression of SNHG3 and miR‑326 was found to be strongly negative in these samples. Additionally, we found that inhibition of SNHG3 caused a partially reversal in the inhibition exerted by miR‑326 on the ability of these cells to proliferate, form colonies, migrate and invade. Collectively, these findings suggest the functioning of SNHG3 as a ceRNA to enhance the ability of breast cancer cells to proliferate and metastasize to putatively serve as a new target to explore therapeutic intervention of this malignancy.

Reprogrammed energy metabolism, especially the Warburg effect (aerobic glycolysis), is an emerging hallmark of cancer. Different from other breast cancer subtypes, triple-negative breast cancer (TNBC) exhibits high metabolic remodeling, increased aggressiveness and lack of targeted therapies. MicroRNAs (miRNA) are essential to TNBC malignant phenotypes. However, little is known about the contribution of miRNA to aerobic glycolysis in TNBC. Through an integrated analysis and functional verification, we reported that several miRNAs significantly correlates to the Warburg effect in TNBC, including miR-210-3p, miR-105-5p, and miR-767-5p. Ectopic expression of miR-210-3p enhanced glucose uptake, lactate production, extracellular acidification rate, colony formation ability, and reduced serum starvation-induced cell apoptosis. Moreover, GPD1L and CYGB were identified as two functional mediators of miR-210-3p in TNBC. Mechanistically, miR-210-3p targeted GPD1L to maintain HIF-1α stabilization and suppressed p53 activity via CYGB. Ultimately, miR-210-3p facilitated aerobic glycolysis through modulating the downstream glycolytic genes of HIF-1α and p53. Taken together, our results decipher miRNAs that regulate aerobic glycolysis and uncover that miR-210-3p specifically contributes to the Warburg effect in TNBC.

Purpose: The incidence of papillary thyroid cancer (PTC) is increasing, and traditional diagnostic methods are unsatisfactory. Therefore, identifying novel prognostic markers is very important. ciRS-7 has been found to play an important role in many cancers, but its role in PTC has not been reported. This study was performed to evaluate the biological role and mechanism of ciRS-7 in PTC. Material and Methods . The expression of ciRS-7 in PTC tissues and the matched adjacent tissues was determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The PTC cell lines (TPC-1 and BCPAP) were used to evaluate the role of ciRS-7. ciRS-7-siRNA and overexpression plasmid were constructed and transfected into PTC cells. A CCK-8 assay and colony formation assay were performed to explore the effects of ciRS-7 on cell proliferation. Annexin V/PI staining and FACS detection were used to detect cell apoptosis. Wound healing assay was performed to detect cell migration. A transwell assay was conducted to explore the effects of ciRS-7 on invasion and migration. Western blotting was performed to evaluate protein expression. The luciferase reporter system was used to determine the underlying mechanism of miR-7., Result: ciRS-7 was highly expressed in PTC tissues and cell lines compared with the corresponding controls. In vitro study showed that ciRS-7 silencing suppressed proliferation, migration, and invasion of TPC-1 and BCPAP. Mechanistically, the effects of ciRS-7 on invasion and migration may be related to epithelial-mesenchymal transition (EMT). ciRS-7 silencing could attenuate effects on PTC cells induced by miR-7 knockdown. Epidermal growth factor receptor (EGFR), which was demonstrated to be a target of miR-7, decreased significantly in ciRS-7-siRNA PTC cells. Overexpression of EGFR also attenuated effects of PTC cells induced by silencing ciRS-7., Conclusion: ciRS-7 was significantly upregulated in PTC tissues, and it promoted the progression of PTC by regulating the miR-7/EGFR axis. ciRS-7 is a promising prognostic biomarker and therapeutic target in PTC., Competing Interests: The authors declare no conflict of interest., (Copyright © 2020 Jun-ya Han et al.)

Objective: Acute lung injury (ALI) is a severe lung disease with high mortality rate. Research has highlighted that the immune response to ALI is associated with significant changes in the expression of several microRNAs (miRNAs) in the lungs. In our research, we speculated that miR-124 moderated the severity of ALI through comprehensive suppression of the mitogen-activated protein kinase (MAPK) signaling pathway activation by targeting MAPK14., Methods: A mouse model of ALI was established by array of experiments. The expression of MAPK14 and miR-124 was assessed in the tissues of ALI mice and the expression of inflammatory cytokines in ALI mice was determined. The expression of the related kinases in the MAPK signaling pathway and key cytokines in the pro-inflammatory response were assessed by a series of experiments. Immunohistochemistry and TUNEL staining were adopted to detect lung tissue cell proliferation and apoptosis in mice with ALI., Results: MiR-124 was poorly expressed and MAPK14 was highly expressed in tissues of ALI mice. Overexpression of miR-124 or silence of MAPK14 alleviated the symptoms of ALI by down-regulating inflammatory cytokines expression, which could intrinsically suppress the expression of associated proteins in the MAPK signaling pathway and the downstream pro-inflammatory response factors, promote proliferation and inhibit apoptosis of lung tissue cells. Overexpression of MAPK14 inverted the phenotypic changes induced by overexpressing miR-124., Conclusion: These results indicated that miR-124 could alleviate the symptoms of ALI by inhibiting the activation of MAPK signaling pathway via subsequent targeting of MAPK14. Additionally, miR-124 may serve as a useful biomarker to alleviate the severity of septic shock-induced lung injury., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objective: To clarify the function of microRNA-15a in the spinal cord injury (SCI) and its potential mechanism., Patients and Methods: The plasma levels of microRNA-15a and signal transducer and activator of transcription 3 (STAT3) in SCI patients were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between the expressions of microRNA-15a and STAT3 was analyzed. The in vitro SCI model was established in H2O2-induced C8-D1A and C8B4 cells, and in vivo SCI model was established in mice by hitting T10. The mRNA and protein expressions of tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) were detected in the SCI model. The apoptosis was examined by flow cytometry or TUNEL staining, respectively. The motor function of mouse hindlimb was evaluated using the Basso Beattie Bresnahan (BBB) standard scale. The target gene of microRNA-15a was predicted by bioinformatics and further verified by dual-luciferase reporter gene assay. The expression changes of target genes in C8-D1A and C8B4 cells with microRNA-15a overexpression or knockdown were examined by qRT-PCR and Western blot. Finally, rescue experiments were performed to evaluate the regulatory effects of microRNA-15a and STAT3 on cell apoptosis., Results: MicroRNA-15a was lowly expressed in plasma of SCI patients, while STAT3 was highly expressed with a negative correlation to microRNA-15a. Identically, microRNA-15a was lowly expressed in H2O2-induced C8-D1A and C8B4 cells, and STAT3 was highly expressed. MicroRNA-15a overexpression downregulated mRNA and protein levels of TNF-α and IL-6 in C8-D1A and C8B4 cells. BBB score was markedly low in SCI mice relative to controls. SCI mice injected with microRNA-15a mimics had higher BBB score than those injected with negative control. Besides, SCI mice with microRNA-15a overexpression had downregulated expressions of STAT3, TNF-α, and IL-6 in the impaired spinal cord tissues, as well as lower apoptotic rate. Through bioinformatics, we found binding sites between STAT3 and microRNA-15a. Their binding conditions were further verified by dual-luciferase reporter gene assay. Moreover, STAT3 expression was negatively regulated by microRNA-15a. Finally, rescue experiments showed that STAT3 overexpression could reverse the regulatory effects of microRNA-15a on expressions of TNF-α and IL-6, as well as apoptosis., Conclusions: MicroRNA-15a expression decreases in the SCI model, which participates in the process of SCI by regulating inflammatory response and cell apoptosis via targeting STAT3.

Background: Previous studies have demonstrated pivotal roles of disintegrin and metalloproteinase 10 (ADAM10) in the pathogenesis of sepsis. MicroRNA- (miR-) 23b has emerged as an anti-inflammatory factor that prevents multiple autoimmune diseases. However, the underlying mechanisms of miR-23b in the regulation of ADAM10 and sepsis remain uncharacterized., Methods: The expression levels of ADAM10 and miR-23b were detected by quantitative RT-PCR and western blot analysis. Cytokine production and THP-1 cell apoptosis were measured by enzyme-linked immunosorbent and annexin V apoptosis assays. Bioinformatics analyses and qRT-PCR, western blot, and luciferase reporter assays were performed to identify ADAM10 as the target gene of miR-23b., Results: miR-23b expression was downregulated in the peripheral blood mononuclear cells of sepsis patients and LPS-induced THP-1 cells and was negatively correlated with the expression of ADAM10 and inflammatory cytokines. miR-23b regulated ADAM10 expression by directly binding to the 3'-UTR of ADAM10 mRNA. The overexpression of miR-23b alleviated the LPS-stimulated production of inflammatory cytokines (TNF- α , IL-1 β , and IL-6) and apoptosis by targeting ADAM10 in THP-1 cells. The inhibitor or knockdown of ADAM10 elicited effects similar to those of miR-23b on THP-1 cells upon LPS stimulation., Conclusions: The present study demonstrated that miR-23b negatively regulated LPS-induced inflammatory responses by targeting ADAM10. The molecular regulatory mechanism of miR-23b in ADAM10 expression and sepsis-induced inflammatory consequences may provide potential therapeutic targets for sepsis., Competing Interests: The authors declare that they have no conflict of interests regarding the publication of this paper., (Copyright © 2019 Wenying Zhang et al.)

Objective: This study aims to elucidate the regulatory effect of circular RNA UBAP2 (circUBAP2) on the progression of ovarian cancer (OC)., Patients and Methods: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to detect the expressions of circUBAP2, microRNA-144 and CHD2 in OC tissues and adjacent normal tissues. The correlation between the expression levels of circUBAP2 and microRNA-144 with pathological parameters of OC patients was analyzed. Subcellular distribution of circUBAP2 was detected by chromatin fractionation assay. After overexpression of circUBAP2 in OC cells, changes in proliferative and migratory abilities were evaluated by Cell Counting Kit-8 (CCK-8) and transwell assay, respectively. In addition, the Dual-Luciferase reporter gene assay was used to verify the binding of circUBAP2 and microRNA-144, and the binding of CHD2 to microRNA-144., Results: QRT-PCR results showed that circUBAP2 was highly expressed in OC tissues, and its expression was negatively correlated with TMN stage and five-year survival of OC patients. CircUBAP2 was mainly distributed in the cytoplasm. Overexpression of circUBAP2 significantly promoted the proliferative and migratory abilities of OC cells. The Dual-Luciferase reporter gene assay demonstrated that circUBAP2 could bind to microRNA-144. Meanwhile, circUBAP2 negatively regulated microRNA-144 expression in OC cells. Besides, the promotive effects of circUBAP2 on the proliferation and migration of OC cells were reversed by microRNA-144 overexpression. MicroRNA-144 was lowly expressed in OC tissues, which was negatively correlated with TNM stage of OC patients. The Dual-Luciferase reporter gene assay confirmed the binding condition between CHD2 and microRNA-144. CHD2 expression was negatively regulated by microRNA-144 in OC cells. Moreover, CHD2 could bind to microRNA-144 and partially inhibited its activity, thereby promoting the proliferative and migratory abilities of OC cells., Conclusions: CircUBAP2 promotes the progression of ovarian cancer by adsorbing microRNA-144.

Parkinson's disease (PD) is a common progressive neurodegenerative disorder occurring in older individuals. Mechanistically, neuroinflammation is a central pathological change in the progression of PD. Activation of microglia is widely considered to be a major trigger for neuroinflammation. Certain microRNAs (miRs) are key factors in inhibiting or stimulating inflammation during the occurrence and development of PD, among which miR‑195 may be a potential crucial biomarker. However, the underlying pathological mechanisms remain unclear. To investigate the pathogenesis of PD, lipopolysaccharide (LPS) was used to establish an in vitro model of microglia activation in the present study. It was revealed that miR‑195 expression was decreased in LPS‑stimulated BV2 cells, suggesting a potential mechanism of action of miR‑195 on microglia activation. Furthermore, gain‑ and loss‑of‑function experiments were performed by successful transfection of microglia with miR‑195 mimics or inhibitors. The results demonstrated that miR‑195 overexpression inhibited the release of pro‑inflammatory cytokines, including inducible nitric oxide synthase, interleukin‑6 (IL‑6) and tumor necrosis factor‑α, but induced the release of anti‑inflammatory cytokines in LPS‑treated BV2 cells, including IL‑4 and IL‑10. In addition, Rho‑associated kinase 1 (ROCK1), which is negatively regulated by miR‑195, was increased in LPS‑stimulated BV2 cells. ROCK1 knockdown with small interfering RNA exhibited the same effect as miR‑195 overexpression on regulating microglia status, suggesting that the miR‑195/ROCK1 interaction serves a central role in inducing microglia activation. Furthermore, inhibition of ROCK1 impaired cell viability and proliferation but induced cell apoptosis in LPS‑treated miR‑195‑deficient BV2 cells. The present results suggest that miR‑195 is a potential therapeutic target for PD.

Tauopathies are a class of neurodegenerative diseases that are characterized by pathological aggregation of tau protein, which is accompanied by synaptic disorders. However, the role of tau in endocytosis, a fundamental process in synaptic transmission, remains elusive. Here, we report that forced expression of human tau (hTau) in mouse cortical neurons impairs endocytosis by decreasing the level of the GTPase dynamin 1 via disruption of the miR-132-MeCP2 pathway; this process can also be detected in the brains of Alzheimer's patients and hTau mice. Our results provide evidence for a novel role of tau in the regulation of presynaptic function., (© 2019 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.)

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., (© 2018 Wiley Periodicals, Inc.)

Impairments of dendritic trees and spines have been found in many neurodegenerative diseases, including Alzheimer's disease (AD), in which the deficits of melatonin signal pathway were reported. Melatonin receptor 2 (MT2) is widely expressed in the hippocampus and mediates the biological functions of melatonin. It is known that melatonin application is protective to dendritic abnormalities in AD. However, whether MT2 is involved in the neuroprotection and the underlying mechanisms are not clear. Here, we first found that MT2 is dramatically reduced in the dendritic compartment upon the insult of oligomer Aβ. MT2 activation prevented the Aβ-induced disruption of dendritic complexity and spine. Importantly, activation of MT2 decreased cAMP, which in turn inactivated transcriptional factor CCAAT/enhancer-binding protein α(C/EBPα) to suppress miR-125b expression and elevate the expression of its target, GluN2A. In addition, miR-125b mimics fully blocked the protective effects of MT2 activation on dendritic trees and spines. Finally, injection of a lentivirus containing a miR-125b sponge into the hippocampus of APP/PS1 mice effectively rescued the dendritic abnormalities and learning/memory impairments. Our data demonstrated that the cAMP-C/EBPα/miR-125b/GluN2A signaling pathway is important to the neuroprotective effects of MT2 activation in Aβ-induced dendritic injuries and learning/memory disorders, providing a novel therapeutic target for the treatment of AD synaptopathy., (© 2019 The Authors. Aging Cell published by Anatomical Society and John Wiley & Sons Ltd.)

Background: LncRNA ZFAS1 (ZNFX1 antisense RNA1) plays key roles in the occurrence and progression of various cancers, including colorectal cancer, glioma, lung cancer, gastric cancer, and so on. To date, relatively little is known about its potential role in development and/or progression of clear cell renal cell carcinoma (ccRCC)., Methods: Expression level of ZFAS1 and miR-10a in 60 ccRCC and 20 adjacent non-tumor tissues were determined by using qRT-PCR. The effect of knockdown of ZFAS1 on cell proliferation, migration and invasion were measured by CCK-8 assay, transwell migration and invasion assay, respectively. The correlation of ZFAS1 and miR-10a was analyzed by bioinformatics DIANA TOOLS. Protein and mRNA expression of spindle and kinetochore-associated protein 1(SKA1) were determined by western blot and qRT-PCR analysis, respectively. Interactions between ZFAS1 and miR-10a were verified by luciferase reporter assay and RNA immunoprecipitation (RIP) assay, and interactions between miR-10a and SKA1 was verified by a luciferase reporter assay., Results: We observed that high-level expression of ZFAS1 is positively correlated with poor prognosis and shorter overall survival (OS) in patients with ccRCC. Knockdown of ZFAS1 significantly suppressed proliferation, migration and invasion of ccRCC cells. Furthermore, miR-10a was identified as a target of ZFAS1. Silencing miR-10a could attenuate the ability of ZFAS1 in promoting proliferation and metastasis of ccRCC. Subsequently, our studies validated that SKA1, as a key downstream target protein for miR-10a, is responsible for the biological role of ZFAS1. ZFAS1 positively regulated SKA1 expression via sponging miR-10a., Conclusions: Taken together, our findings suggest that ZFAS1 promotes growth and metastasis of ccRCC via targeting miR-10a/SKA1 pathway, which may represent a novel therapeutic target or biomarker for ccRCC., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Objectives: The aim of this study was to explore the value of serum miRNA for evaluating renal tissue activity in patients with class IV lupus nephritis (LN)., Methods: First, we used a microRNA array to identify miRNAs differentially expressed between class IV LN patients and healthy volunteers (n=4/group). Then, we analysed the association between these identified miRNAs and renal tissue activity in class IV LN patients. Finally, to validate the results, 20 class IV LN patients (confirmed by renal biopsy) and 20 healthy control volunteers were further studied., Results: We found 23 miRNAs to be significantly differentially expressed between the 2 groups. We selected 5 of these miRNAs (miR-3165, miR-4762-5p, miR-146a-5p, miR-151a-3p, and miR-21-5p) for further experiments. In validation experiments, expression of miRNA-151a-3p was significantly down-regulated in the class IV LN group compared to that in the control group (p<0.01) and was negatively correlated with the activity index (AI) in the class IV LN group(r=-0.526, p=0.017); the internal correlation was described with a linear fitting equation (p<0.01)., Conclusions: Serum miR-151a-3p expression was decreased in class IV LN patients compared with healthy control volunteers and was negatively correlated with renal tissue activity. Thus, miR-151a-3p may play a employed for diagnosing class IV LN and evaluating renal tissue activity.

MiR-155 can inhibit the formation of atherosclerosis by interfering with the transformation of macrophages into foam cells that plays a critical role in the pathogenesis of atherosclerosis, but the precise mechanisms of miR-155 are still unknown. Herein, we observed that mRNA and protein expression levels of CEH were significantly upregulated in a dose- and time-dependent manner by transfected with miR-155 mimics in THP-1 macrophages. Further studies showed that overexpression of miR-155 can significantly inhibit foam cells formation, reduce intracellular CE accumulation and enhance the efflux of FC and cholesterol, result in a decrease of intracellular lipid accumulation; while this effect was significantly reversed by siCEH. Meanwhile, we found that Tim-3 is associated with miR-155-mediated CEH expression in THP-1 macrophage-derived foam cells. Overexpression of Tim-3 can attenuate miR-155-mediated CEH induction. Taken together, our findings demonstrated that miR-155 can inhibit the transformation of macrophages into foam cells by enhancing CEH signaling pathway in macrophages, this effect is likely to be achieved by inhibiting the expression of Tim-3., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Objective: Long non-coding RNA ZEB1-AS1 (ZEB1-AS1) was reported to be implicated and aberrantly expressed in multiple cancers. However, the potential mechanism and clinical significance of ZEB1-AS1 in the carcinogenesis of glioma remain unclear., Patients and Methods: RT-PCR was performed to determine the expression of ZEB1-AS1 in glioma tissues and cell lines. The association between ZEB1-AS1 expression and clinical features and prognosis were statistically analyzed. MTT and transwell assays were used to test the proliferation, invasion, and migration of glioma cells. Luciferase report assay was used to detect the correlation between ZEB1-AS1 and miR-577 in glioma., Results: Compared with normal brain tissues and cells, ZEB1-AS1 in glioma tissues and cell lines was shown to be expressed at high levels. Clinical association analysis indicated that ZEB1-AS1 expression was closely associated with tumor size (p = 0.014), KPS (p = 0.004) and WHO grade (p = 0.001). In addition, it was observed that high expression level of ZEB1-AS1 was remarkably associated with overall survival and could be an independent prognostic indicator of glioma using univariate and multivariate analysis. Functional experiments demonstrated that down-regulation of ZEB1-AS1 suppressed the proliferation, invasion, and migration of glioma cell in vitro. In the mechanism, we found that ZEB1-AS1 acted as a competing endogenous RNA to sponge miR-577. Moreover, miR-577 could reverse the tumor-promotive role of ZEB1-AS1 on glioma cells., Conclusions: Our findings demonstrated that ZEB1-AS1 might play an oncogenic role in glioma and was a poor prognostic factor. The ZEB1-AS1/miR-577 axis might be a potential target for the development of effective glioma therapy.

Background: Synaptic loss is an early pathological event in Alzheimer's disease (AD), but its underlying molecular mechanisms remain largely unknown. Recently, microRNAs (miRNAs) have emerged as important modulators of synaptic function and memory., Methods: We used miRNA array and quantitative polymerase chain reaction to examine the alteration of miRNAs in AD mice and patients as well as the Morris water maze to evaluate learning and memory in the mice. We also used adeno-associated virus or lentivirus to introduce tyrosine-protein phosphatase non-receptor type 1 (PTPN1) expression of silencing RNAs. Long-term potentiation and Golgi staining were used to evaluate the synaptic function and structure. We designed a peptide to interrupt miR-124/PTPN1 interaction., Results: Here we report that neuronal miR-124 is dramatically increased in the hippocampus of Tg2576 mice, a recognized AD mouse model. Similar changes were observed in specific brain regions of affected AD individuals. We further identified PTPN1 as a direct target of miR-124. Overexpression of miR-124 or knockdown of PTPN1 recapitulated AD-like phenotypes in mice, including deficits in synaptic transmission and plasticity as well as memory by impairing the glutamate receptor 2 membrane insertion. Most importantly, rebuilding the miR-124/PTPN1 pathway by suppression of miR-124, overexpression of PTPN1, or application of a peptide that disrupts the miR-124/PTPN1 interaction could restore synaptic failure and memory deficits., Conclusions: Taken together, these results identified the miR-124/PTPN1 pathway as a critical mediator of synaptic dysfunction and memory loss in AD, and the miR-124/PTPN1 pathway could be considered as a promising novel therapeutic target for AD patients., (Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Purpose: Retinoblastoma (Rb) is the most common intraocular tumor in children. MicroRNAs (miRNAs) play a crucial role in gene regulation and cell growth/apoptosis/differentiation. The current study aimed to investigate the role of miR-498 in Rb., Methods: Quantitative real-time polymerase chain reaction (QRT-PCR) was used to test mRNA level of miR-498. http://www.targetscan.org and http://www.microrna.org were applied to predict target of miR-498. Dual-luciferase reporter assay was applied to investigate if miR-498 targeted cell cycle progression 1 (CCPG1). Western blot (WB) was carried out to assess CCPG1 protein levels. 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay was used to evaluate cell proliferation. Annexin-V Fluorescein (FITC) was adopted to explore cell apoptosis., Results: In Y79 cells, miR-498 was higher than in normal ARPE-19 cells. MiR-498 could recognize CCPG1-3' untranslated region (UTR). CCPG1 protein level was remarkably decreased when overexpressed miR-498, nevertheless, significantly increased when inhibiting miR-498. Y79 cells that were transfected with miR-498 mimics manifested notable cell apoptosis down-regulation and cell proliferation promotion; whereas, those transfected with miR-498 inhibitor displayed significant cell apoptosis up-regulation and cell proliferation inhibition compared with control group., Conclusion: Taken together, miR-498 promotes cell proliferation and inhibits cell apoptosis in Rb by directly targeting CCPG1.

Background: Although O(6)-methylguanine DNA methyltransferase (MGMT) promoter methylation status is an important marker for glioblastoma multiforme (GBM), there is considerable variability in the clinical outcome of patients with similar methylation profles., Objective: We examined whether a MicroRNA (miRNA) signature can be identified for predicting clinical outcomes and helping in treatment decisions., Methods: The differentially expressed miRNAs were evaluated in 6 pairs of short- (⩽ 450 days) and long-term survivors (> 450 days) by using microarray. Real time quantitative PCR (qRT-PCR) was applied to further verify screened miRNAs with a greater number of samples (n= 48). Meanwhile, functional interpretation of miRNA profile was carried out based on miRNA-target databases. In addition, MGMT promoter methylation status was tested by means of pyrosequencing (PSQ) testing., Results: Six miRNAs were upregulated in the long-term survival group (fold change ⩾ 2.0, P< 0.05). The further verification by qRT-PCR indicated that the increase in let-7g-5p, miR-139-5p, miR-17-5p and miR-9-3p level in long-term survivors was statistically significant. Kaplan-Meier survival analysis showed that high expression of a prognostic 4-miRNA signature was significantly associated with good patient survival (p= 0.0012). The signature regulated signaling pathways including Calcium, MAPK, ErbB, mTOR and cell cycle involved in carcinogenesis from glial progenitor cell to primary GBM., Conclusions: The 4-miRNA signature was identified as an independent prognostic biomarker that identified patients who have a favorable outcome.

Histone deacetylase 2 (HDAC2) plays a major role in the epigenetic regulation of gene expression. Previous studies have shown that HDAC2 expression is strongly increased in Alzheimer's disease (AD), a major neurodegenerative disorder and the most common form of dementia. Moreover, previous studies have linked HDAC2 to Aβ overproduction in AD; however, its involvement in tau pathology and other memory-related functions remains unclear. Here, we show that increased HDAC2 levels strongly correlate with phosphorylated tau in a mouse model of AD. HDAC2 overexpression induced AD-like tau hyperphosphorylation and aggregation, which were accompanied by a loss of dendritic complexity and spine density. The ectopic expression of HDAC2 resulted in the deacetylation of the hepatocyte nuclear factor 4α (HNF-4A) transcription factor, which disrupted its binding to the miR-101b promoter. The suppression of miR-101b caused an upregulation of its target, AMP-activated protein kinase (AMPK). The introduction of miR-101b mimics or small interfering RNAs (siRNAs) against AMPK blocked HDAC2-induced tauopathy and dendritic impairments in vitro. Correspondingly, miR-101b mimics or AMPK siRNAs rescued tau pathology, dendritic abnormalities, and memory deficits in AD mice. Taken together, the current findings implicate the HDAC2/miR-101/AMPK pathway as a critical mediator of AD pathogenesis. These studies also highlight the importance of epigenetics in AD and provide novel therapeutic targets., (Copyright © 2017 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.)

Ischemic strokes occur as a result of an obstruction within a blood vessel supplying blood to the brain and accounts for about 87 % of all cases. During the cerebral ischemia, most of the neurons undergo the necrosis and apoptosis upon the exposure to the dramatic blood flow reduction. Although, it is known that both the intrinsic and extrinsic pathways are involved in the neuronal apoptosis of ischemic brain injury. The complex underlying mechanisms remains less known. MicroRNAs are a class of endogenous small non-coding RNAs and the role of miRNAs in the pathophysiology of stroke has been studied. In this study, we found that miR-9 is downregulated in the mice with middle cerebral artery occlusion (MCAO) brain and oxygen-glucose deprivation (OGD) neurons. Application of miR-9 gamer could restore the neurological scores and reduces the infarct volume, brain water content, and the behavioral impairments. Moreover, upregulation of miR-9 suppresses the neuronal apoptosis in MCAO brain and OGD neurons. Furthermore, we identified that Bcl2l11 as the direct target of miR-9 and manipulation of miR-9 induces the corresponding changing of Bcl2l11 protein level. Finally, we found that the protein level of Bcl2l11 is increased in the MCAO brain and OGD neurons. Our study demonstrated the critical role of miR-9 in the neuronal apoptosis of ischemic brain injury.

Malignant astrocytomas are the most common primary brain tumors. The critical characterizes of astrocyomas are their aggressive and infiltrative in the brain, which leads to uncontrollable by conventional forms of therapy. MicroRNAs are small RNAs that had been found to regulate their targets by specific binding to the 3'-untranslated region (3'UTR) of mRNA. Recent advances in understanding the molecular biology of these tumors have revealed that microRNA (miRNA) disruption may play important roles in the pathogenesis of astrocytomas. And some of the miRNA alterations were found in the serum of astrocytoma patients. In this study, we studied the expression profile of miR-128, in the different stages of astrocytoma tissues and two human astrocytoma cell lines, A172 and T98G cells. We found that the levels of miR-128 are decreased in the A172 and T98G cells when compared to normal human astrocyte (NHA). Furthermore, the levels of miR-128 decreased gradually to the pathological stages of astrocytomas. We also identified that TROVE2 is a novel target of miR-128 by the luciferase reporter system. Furthermore, the expression levels of TROVE2 are dramatically increased with the pathological stages increasing. Finally, the levels of TROVE2 are negatively correlated with miR-128 in astrocytoma tissues. Our data provided novel evidence for the miR-128 and TROVE2 in the development of human astrocytomas.

A large number of etiological factors and the complexity of breast cancers present challenges for prevention and treatment. Recently, the emergence of microRNAs (miRNAs) as cancer biomarkers has added an extra dimension to the 'molecular signatures' of breast cancer. Bioinformatic analyses indicate that each miRNA can regulate hundreds of target genes and could serve functionally as 'oncogenes' or 'tumour suppressor' genes, and co-ordinate multiple cellular processes relevant to cancer progression. A number of studies have shown that miRNAs play important roles in breast tumorigenesis, metastasis, proliferation and differentiation of breast cancer cells. This review provides a comprehensive overview of miRNAs with established functional relevance in breast cancer, their established target genes and resulting cellular phenotype. The role and application of circulating miRNAs in breast cancer is also discussed. Furthermore, we summarize the role of miRNAs in the hallmarks of breast cancer, as well as the possibility of using miRNAs as potential biomarkers for detection of breast cancer., (© 2015 Cambridge Philosophical Society.)

Autophagy is a catabolic process widely conserved among eukaryotes that permits the rapid degradation of unwanted proteins and organelles through the lysosomal pathway. The Serine/threonine protein kinase ULK2 (unc-51 like kinase 2) plays an important regulatory role in autophagy thanks to its involvement in mTOR-regulated-initiation and downstream ATG protein-related progression of this catabolic process. An increasing number of miRNAs have been found to modulate autophagy by targeting some ATG genes. In this study, we focus on the role of mir-26b in autophagy in prostate cancer (PCa) cells. We found that miR-26b inhibited autophagy in PC-3 and C4-2 cells, through down-regulation of ULK2 expression. Dual luciferase reporter assays showed that miR-26b binds the 3'UTR of ULK2, suggesting that ULK2 is a direct target of miR-26b. Real-time PCR and Western blot analysis confirmed that over-expression of miR-26b reduced ULK2 mRNA and protein levels. Our results showed also that miR-26b was down-regulated in LNCaP, DU145, C4-2 and PC-3 cells compared to the two normal prostate cells RWPE-1 and WPMY-1 except DU145 cells. This inversely correlates with ULK2 level in the same cell lines. Expression level of ULK2 in tissues microarray (TMA) of prostate cancer derived from 96 patients positively correlated with the pathologic stage of the patients (∗P < 0.05). Over-expression of ULK2 significantly reversed miR-26b-mediated autophagy inhibition. Taken together, our findings indicate that mir-26b inhibits autophagy through targeting ULK2 which is up-regulated in PCa., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

The two estrogen receptors (ERs), ERα and ERβ, mediate the diverse biological functions of estradiol. Opposite effects of ERα and ERβ have been found in estrogen-induced cancer cell proliferation and differentiation as well as in memory-related tasks. However, whether these opposite effects are implicated in the pathogenesis of Alzheimer's disease (AD) remains unclear. Here, we find that ERα and ERβ play contrasting roles in regulating tau phosphorylation, which is a pathological hallmark of AD. ERα increases the expression of miR-218 to suppress the protein levels of its specific target, protein tyrosine phosphatase α (PTPα). The downregulation of PTPα results in the abnormal tyrosine hyperphosphorylation of glycogen synthase kinase-3β (resulting in activation) and protein phosphatase 2A (resulting in inactivation), the major tau kinase and phosphatase. Suppressing the increased expression of miR-218 inhibits the ERα-induced tau hyperphosphorylation as well as the PTPα decline. In contrast, ERβ inhibits tau phosphorylation by limiting miR-218 levels and restoring the miR-218 levels antagonized the attenuation of tau phosphorylation by ERβ. These data reveal for the first time opposing roles for ERα and ERβ in AD pathogenesis and suggest potential therapeutic targets for AD., (© 2015 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.)

Natural antisense transcripts (NATs) exist ubiquitously as pivotal molecules to regulate coding gene expression. Sirtuin 1 (Sirt1) is a NAD-dependent deacetylase which is involved in myogenesis. However, whether Sirt1 transcribes NAT during C2C12 differentiation is still unknown. In this study, we identified a Sirt1 NAT which was designated as Sirt1 antisense long non-coding RNA (AS lncRNA) by sequencing and bioinformatic analysis. The level of Sirt1 AS lncRNA was greater in spleen but less in muscle tissue. The expression of both Sirt1 mRNA and Sirt1 AS lncRNA decreased during C2C12 myogenic differentiation, whereas the levels of miR-34a, which targets Sirt1, increased gradually. We further found that the half-life of Sirt1 AS lncRNA was 10h, but that of Sirt1 mRNA was 6h in C2C12 cells treated with 2 μg/ml Actinomycin D. Therefore, compared with Sirt1 mRNA, Sirt1 AS lncRNA was more stable. Overexpression of Sirt1 AS lncRNA increased the levels of Sirt1 protein, whereas overexpression of Sirt1 AS lncRNA mutant did not affect the level of Sirt1 protein in C2C12 cells. Moreover, downregulation of Sirt1 mRNA caused by miR-34a was counteracted by Sirt1 AS lncRNA in C2C12 cells. Taken together, we identified a novel NAT of Sirt1 which implicated in myogenesis through regulating Sirt1 expression., (Copyright © 2014 Elsevier B.V. All rights reserved.)

To clarify the function and molecular mechanism of miR-155 in myogenic differentiation of C2C12, we constructed adenovirus over-expression vector of miR-155, then C2C12 cells were infected by adenovirus and induced myogenic differentiation. First, we observed the morphology of C2C12 after differentiation. Then the mRNA and protein expressions of myogenic markers (MyoD, MyoG and MyHC) were detected by qPCR and western blotting. Subsequently, the dual luciferase reporter gene assay was carried out to validate putative target gene (TCF4) of miR-155. Meanwhile, mRNA level of TCF4 was analyzed after over-expressing miR-155. The results show that over-expressed miR-155 reduced myotubes formation. Moreover, the mRNA and protein expression of MyoG and MyHC decreased significantly (P < 0.01). Further research demonstrated miR-155 bound the one (4532-4538) of three putative sites (1487-1493,1516-1522, 4532-4583) of TCF4 by luciferase reporter gene assay and the mRNA level of TCF4 decreased notably (P < 0.05). The data suggest that miR-155 inhibited myogenic differentiation of C2C12 through targeted TCF4.

Previous studies have suggested that microRNAs (miRNAs) may play important roles in tumorigenesis, but little is known about the functions of most miRNAs in cancer development. In the present study, we set up a cell-based screen using a luciferase reporter plasmid carrying the whole approximately 4.7 kb 3'-UTR of estrogen receptor alpha (ERalpha) mRNA cotransfected with a synthetic miRNA expression library to identify potential ERalpha-targeting miRNAs. Among all the miRNAs, miR-22 was found to repress robustly the luciferase signal in both HEK-293T and ERalpha-positive MCF-7 cells. Mutation of the target site was found to abrogate this repression effect of miR-22, whereas antagonism of endogenous miR-22 in MDA-MB-231 cells resulted in elevated reporter signals. We assessed the miR-22 expression patterns in five breast cancer cell lines and 23 clinical biopsies and revealed that there is a significant inverse association between the miR-22 levels and ERalpha protein expression. To evaluate the potential of miR-22 as a potential therapeutic intervention, we found that reduction of endogenous ERalpha protein levels and suppression of cancer cell growth could be achieved in MCF-7 cells by miR-22 overexpression in a way that can be recapitulated by the introduction of specific small interfering RNA against ERalpha. The phenomena can be rescued by the reintroduction of ERalpha. Taken together, our data indicate that miR-22 was frequently downregulated in ERalpha-positive human breast cancer cell lines and clinical samples. Direct involvement in the regulation of ERalpha may be one of the mechanisms through which miR-22 could play a pivotal role in the pathogenesis of breast cancer.

Objective MicroRNAs are a class of endogenous small regulatory RNAs that regulate cell proliferation, differentiation and apoptosis. Recent studies on miRNAs are mainly focused on mice, human and pig. However, the studies on miRNAs in skeletal muscle of sheep are not comprehensive. Methods RNA-seq technology was used to perform genomic analysis of miRNAs in prenatal and postnatal skeletal muscle of sheep. Targeted genes were predicted using miRanda software and miRNA-mRNA interactions were verified by quantitative real-time polymerase chain reaction. To further investigate the function of miRNAs, candidate targeted genes were enriched for analysis using gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment. Results The results showed total of 1,086 known miRNAs and 40 new candidate miRNAs were detected in prenatal and postnatal skeletal muscle of sheep. In addition, 345 miRNAs (151 up-regulated, 94 down-regulated) were differentially expressed. Moreover, miRanda software was performed to predict targeted genes of miRNAs, resulting in a total of 2,833 predicted targets, especially miR-381 which targeted multiple muscle-related mRNAs. Furthermore, GO and KEGG pathway analysis confirmed that targeted genes of miRNAs were involved in development of skeletal muscles. Conclusion This study supplements the miRNA database of sheep, which provides valuable information for further study of the biological function of miRNAs in sheep skeletal muscle.

MicroRNAs (miRNAs) are a class of small non-coding RNAs, molecules of 21 to 25 nucleotides in length, that regulate gene expression by binding to their target mRNA and play a significant role in animal development. The expression and role of miRNAs in regulating sheep estrus, however, remain elusive. Transcriptome analysis is helpful to understand the biological roles of miRNAs in the pituitary gland of sheep. A sheep’s pituitary gland has a significant difference between estrus and anestrus states. Here, we investigate the expression profiles of sheep anterior pituitary microRNAs (miRNAs) in two states, estrus and anestrus, using Illumina HiSeq-technology. This study identified a total of 199 miRNAs and 25 differentially expressed miRNAs in the estrus and anestrus pituitary gland in sheep. Reverse transcription quantitative-PCR (RT-qPCR) analysis shows six differentially (p < 0.05) expressed miRNAs, that are miR-143, miR-199a, miR-181a, miR-200a, miR-218, and miR-221 in both estrus and anestrus states. miRNAs containing estrus-related terms and pathways regulation are enriched using enrichment analysis from gene ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). Moreover, we also envisioned a miRNA−mRNA interaction network to understand the function of miRNAs involved in the pituitary gland regulatory network. In conclusion, miRNA expression profiles in sheep pituitary gland in the anestrus and estrus deliver a theoretical basis for the study of pituitary gland biology in sheep.