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MicroRNAs (miRNAs) were involved in tumorigenesis, progression, recurrence and drug resistance of hepatocellular carcinoma (HCC). However, few miRNAs have been identified and entered clinical practice. We show here that miR-4461 expression is reduced in liver cancer stem cells (CSCs) and predicts the poor prognosis of HCC patients. Knockdown of miR-4461 enhances the self-renewal and tumorigenicity of liver CSCs. Conversely, forced miR-4461 expression inhibits liver CSCs self-renewal and tumorigenesis. Mechanically, miR-4461 directly targets sirtuin 1 (SIRT1) via binding to its 3' untranslated region in liver CSCs. The correlation of miR-4461 and SIRT1 was confirmed in human HCC patients' tissues. Additionally, we found that miR-4461 overexpression hepatoma cells are more sensitive to cisplatin treatment. Patient-derived xenografts also showed that miR-4461 high HCC xenografts are sensitive to cisplatin treatment. Clinical cohort analysis further confirmed that HCC patients with high miR-4461 benefited more from transcatheter arterial chemoembolization treatment. In conclusion, our findings revealed the crucial role of miR-4461 in liver CSCs expansion and cisplatin response, rendering miR-4461 as an optimal target for the prevention and intervention of HCC., (© The Author(s) 2022. Published by Oxford University Press. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Breast cancer (BC) is a common cancer whose incidence continues to grow while its medical progress has stagnated. miRNAs are vital messengers that facilitate communications among different cancer cells. This study was to reveal the correlation of miR-122-3p expression with BC metastasis and Adriamycin (ADM) resistance and its mechanism of inhibiting BC metastasis. We found that expression of miR-122-3p is negatively correlated with BC metastasis and is lower in MCF-7/ADR cells. Overexpression of miR-122-3p in MCF-7/ADR cancer cells impairs their ability to migrate, invade, and stimulate blood vessel formation. Further research found that miR-122-3p directly binds to the 3' UTR of GRK4, reducing the phosphorylation of LRP6, which activates the Wnt/β-catenin signaling pathway, facilitating BC development and metastasis. In addition, we observed that miR-122-3p is present in MCF-7  cells, and treatment of MCF-7/ADR cells with MCF-7-derived exosomes, but not with exosomes from miR-122-3p-deficient MCF-7 cells, has identical effects to miR-122-3p overexpression. Data from xenograft experiments further suggest that excess miR-122-3p and MCF-7-derived exosomes inhibit the growth and metastasis of MCF-7/ADR cancer cells in vivo. In conclusion our data reveal that exosomal miR-122-3p may negatively regulate BC growth and metastasis, potentially serving as a diagnostic and druggable target for BC treatment., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2023. Published by Elsevier Inc.)

Objective: The diminished expression of microRNA-146a (miR-146a) in systemic lupus erythematosus (SLE) contributes to the aberrant activation of the interferon pathway. Despite its significance, the underlying mechanism driving this reduced expression remains elusive. Considering the integral role of enhancers in steering gene expression, our study seeks to pinpoint the SLE-affected enhancers responsible for modulating miR-146a expression. Additionally, we aim to elucidate the mechanisms by which these enhancers influence the contribution of miR-146a to the activation of the interferon pathway., Methods: Circular chromosome conformation capture sequencing and epigenomic profiles were applied to identify candidate enhancers of miR-146a. CRISPR activation was performed to screen functional enhancers. Differential analysis of chromatin accessibility was used to identify SLE-dysregulated enhancers, and the mechanism underlying enhancer dysfunction was investigated by analyzing transcription factor binding. The therapeutic value of a lupus-related enhancer was further evaluated by targeting it in the peripheral blood mononuclear cells (PBMCs) of patients with SLE through a CRISPR activation approach., Results: We identified shared and cell-specific enhancers of miR-146a in distinct immune cells. An enhancer 32.5 kb downstream of miR-146a possesses less accessibility in SLE, and its chromatin openness was negatively correlated with SLE disease activity. Moreover, CCAAT/enhancer binding protein α, a down-regulated transcription factor in patients with SLE, binds to the 32.5-kb enhancer and induces the epigenomic change of this locus. Furthermore, CRISPR-based activation of this enhancer in SLE PBMCs could inhibit the activity of interferon pathway., Conclusion: Our work defines a promising target for SLE intervention. We adopted integrative approaches to define cell-specific and functional enhancers of the SLE critical gene and investigated the mechanism underlying its dysregulation mediated by a lupus-related enhancer., (© 2023 American College of Rheumatology.)

Glioma remains one of the most challenging primary brain malignancies to treat. Long noncoding RNAs (lncRNAs) and mRNAs (mRNAs) are implicated in regulating the malignant phenotypes of cancers including glioma. This study aimed to elucidate the functions and mechanisms of lncRNA LINC00265 and mRNA IFI30 in the pathogenesis of glioma. Quantitative real-time polymerase chain reaction (RT-qPCR) analysis revealed the upregulated expression of LINC00265 and IFI30 in glioma cells compared to normal human astrocytes. Western blot (WB) quantified the associated proteins. Glioma stemness and epithelial-to-mesenchymal transition (EMT) were assessed by aldehyde dehydrogenase 1 (ALDH1) activity, sphere formation, and WB. Mechanistic and rescue assays evaluated the LINC00265/miR-let-7d-5p/IFI30/ZNF384/IGF2BP2 axis. The results demonstrated that LINC00265 and IFI30 were highly expressed in glioma cells, promoting stemness and EMT. ZNF384 was identified as a transcription factor that upregulates IFI30. Moreover, LINC00265 elevated ZNF384 by sponging miR-let-7d-5p and recruiting IGF2BP2. In conclusion, LINC00265 and IFI30 act as oncogenes in glioma by driving stemness and EMT, underscoring their potential as therapeutic targets.

Purpose: Previous studies have found that miR-23a-3p, a diagnostic marker for colon cancer (CC), is upregulated in primary CC from stage I/II patients. Nevertheless, the specific functions and molecular mechanisms of miR-23a-3p in colon cancer remain unclear., Methods: The expression levels of miR-23a-3p and NDRG4 were analyzed by western blot and RT‒qPCR assays. Cell viability and proliferation were measured by CCK8 and colony formation assays. Cell apoptosis was assessed by flow cytometry. Cell migration and invasion were detected by transwell assay. Target binding was detected by luciferase reporter assay., Results: miR-23a-3p was dramatically elevated in CC tissues and cells. In HT29 and SW480 cells, downregulation of miR-23a-3p hampered cell proliferation, migration, and invasion while increasing cell apoptosis. The effects of miR-23a-3p silencing on CC progression were slowed by NDRG4 downregulation., Conclusions: miR-23a-3p promoted CC progression by modulating the expression of NDRG4. This study demonstrated the mechanism of miR-23a-3p in CC, which may offer a new target for CC therapy., (© 2022. The Author(s), under exclusive licence to Federación de Sociedades Españolas de Oncología (FESEO).)

The altered expression of microRNA (miRNA) has been implicated in glioma. Here, the current study aimed to clarify the oncogenic effects of miR-19b-3p on cellular processes of glioma and to elucidate the underlying mechanism associated with SOCS3 and the JAK-STAT signaling pathway. Differentially expressed genes related to glioma were initially identified via microarray analysis. Twenty-five glioma patients were selected for clinical data collection, while additional 12 patients with traumatic brain injuries were selected as controls. Cell senescence was assessed by β-galactosidase staining, proliferation by MTT assay and apoptosis by flow cytometry following gain- and/or loss-of-function of miR-19b-3p or SOCS3. Glioma xenograft mouse model was developed through subcutaneous injection to nude mice to provide evidence in vivo. The glioma patients exhibited overexpressed miR-19b-3p and poorly-expressed SOCS3. SOCS3 was identified as a target gene of miR-19b-3p through dual-luciferase reporter gene assay. miR-19b-3p repressed SOCS3 expression and activated the JAK-STAT signaling pathway. Furthermore, miR-19b-3p inhibition promoted apoptosis and senescence, and suppressed cell proliferation through inactivation of the JAK-STAT signaling pathway and up-regulation of SOCS3. The reported regulatory axis was validated in nude mice as evidenced by suppressed tumor growth. Taken together, this study demonstrates that miR-19b-3p facilitates glioma progression via activation of the JAK-STAT signaling pathway by targeting SOCS3, highlighting a novel therapeutic target for glioma treatment., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Some recent studies have reported the role of circular RNAs (circRNAs) in modulating the tumorigenesis of human malignancies. Nevertheless, the expression characteristics, biological functions, and regulatory mechanism of circ_0000189 in glioma are unclear., Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to detect the expression levels of circ_0000189, miR-192-5p, and ZEB2 mRNA in glioma tissues and cells. The association between the expression of circ_0000189 and the clinicopathological indicators and the features of magnetic resonance imaging (MRI) images of glioma patients were analyzed. Western blot was utilized to evaluate ZEB2 expression and epithelial-mesenchymal transition (EMT-)-related proteins (E-cadherin, N-cadherin, as well as Vimentin) in glioma cells. Cell proliferation was assessed employing cell counting kit-8 (CCK-8) and EdU experiments. Flow cytometry was used to detect the apoptotic rate of the cells. Cell migration and invasion were accessed employing Transwell assay. Moreover, dual luciferase reporter gene assay and RNA immunoprecipitation assay were employed to investigate the targeting relationship between miR-192-5p and circ_0000189, miR-192-5p, and ZEB2. Subcutaneous tumorigenesis experiment and lung metastasis experiment in nude mice were conducted to verify the regulatory function of circ_0000189 on the proliferation and metastasis of glioma cells in vivo ., Results: circ_0000189 was markedly overexpressed in glioma tissues and cell lines. Its high expression was associated with poor clinical pathological indicators and adverse MRI signs. Gain-of-function experiments and loss-of-function experiments confirmed that circ_0000189 overexpression facilitated the proliferation and migration, as well as invasion of glioma cells, and suppressed apoptosis, and facilitated epithelial-mesenchymal transition (EMT) process. Compared to the control group, knocking down circ_0000189 suppressed the malignant phenotypes of glioma cells both in vivo and in vitro . Working as a competitive endogenous RNA, circ_0000189 directly targeted miR-192-5p, and repressed its expression, and circ_0000189 positively modulated ZEB2 expression indirectly via repressing miR-192-5p., Conclusion: circ_0000189 facilitates the progression of glioma by modulating miR-192-5p/ZEB2 axis., Competing Interests: The authors declare that they have no competing interests., (Copyright © 2022 Jian Yang et al.)

Curcumin (Cur), a natural polyphenol compound, has been testified to modulate innate immune responses and also showed anti -inflammatory properties. Nevertheless, the mechanism was still poorly unknown, especially regarding Cur-modulated microRNAs (miRNAs) under the inflammatory response. CD39 + regulatory T cells (Tregs) were provided with distinct immunosuppressive action and exerted a critical role in the modulation of immune balance in sepsis. Nevertheless, the impact of Cur on the immune function of sepsis mice has not been reported. In this study, the influence of Cur on the inflammatory response and immune function of sepsis mice via augment of miR-183-5p and Cathepsin B (CTSB)-mediated phosphatidylinositol 3-kinase (PI3K)/AKT pathway was explored. Adoption of 20 mg/kg Cur was for gavage. In the meantime, injection of plasmid vectors of interference with miR-183-5p or CTSB was into the tail vein. Intraperitoneal injection of lipopolysaccharide (10 mg/kg) was to stimulate model of sepsis mice. Histopathological changes of sepsis mice were observed. The contents of tumor necrosis factor- α and Interleukin (IL)-1 β and IL-6 in serum of mice were examined. Detection of alanine aminotransferase, aspartate aminotransferase (AST), urea nitrogen (BUN), and creatinine in serum of mice was performed. Test of the percentage of CD39 + Tregs in tail venous blood of mice was implemented. Examination of miR-183-5p, CTSB, and PI3K/AKT was performed. The targeting of miR-183-5p and CTSB was detected. Cur was available to ameliorate the histological damage, to reduce the content of inflammatory factors, AST, and BUN, and to decline the percentage of CD39 + Tregs in tail venous blood of sepsis mice. Elevated miR-183-5p or silenced CTSB was available to further enhance the protection of Cur. Cur was available to accelerate miR-183-5p, which negatively modulated CTSB and Cur-mediated PI3K/AKT pathway via the miR-183-5p/CTSB axis to restrain inflammation of sepsis mice and enhance its immune function., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Yanan Liu et al.)

Background: Our previous studies had shown pirfenidone (PFD) not only improved tubulointerstitial fibrosis (TIF) but also inhibited the expression of microRNA-21 (miR-21) in the renal tissue of unilateral urethral obstruction (UUO) rats. This study aims to investigate whether PFD can attenuate TIF through inhibiting miR-21 in UUO rats., Methods: Sprague Dawley rats were divided randomly into sham-operated group, UUO group, and PFD and olmesartan (Olm) treatment groups. Samples were collected on day 14. Expression of miR-21, TGF-β1, Smad3, and Smad7 mRNA in the renal tissue was detected using real-time quantitative PCR. Immunohistochemistry was performed to assess the protein expressions of collagen III, E-cadherin, and α-SMA. Automated capillary Western blotting was used to detect the quantitative expression of TGF-β1, Smad3, p-Smad3, Smad7, collagen III, E-cadherin, and α-SMA in renal tissues. The expression of miR-21 and Smad7 mRNA and the protein levels of collagen III and α-SMA were examined in the miR-21-overexpressing cell line, NRK-52E., Results: Compared with the UUO group, both PFD and Olm inhibited renal tubular dilation, diffused epithelial cell degeneration and necrosis, and reduced renal interstitial edema, inflammatory cell infiltration, and collagen fiber deposition, while no significant difference between PFD group and Olm group. Informatics-based approaches identified Smad7 as a likely candidate for regulation by miR-21. Compared with the sham group, miR-21 expression was upregulated in the UUO group resulting in the downregulation of Smad7 expression due to degradation. The overexpression of miR-21 in the in vitro model downregulated Smad7 and promoted EMT and ECM accumulation. Protein levels of TGF-β1, Smad3, p-Smad3, collagen III, and α-SMA were upregulated, while E-cadherin protein was downregulated in the UUO group than in the sham group. PFD rather than Olm decreased the expression of miR-21 and increased the expression level of Smad7 mRNA and then inhibited the TGF-β1/Smad3 signaling pathway. Olm only downregulated the TGF-β1/Smad3 signaling pathway., Conclusions: PFD improves TIF by downregulating the expression of miR-21, then elevating Smad7, and finally inhibiting the activation of the TGF-β1/Smad3 signaling pathway in UUO rats., (© 2021 S. Karger AG, Basel.)

Accumulating studies revealed association between development of glioma and miRNA dysregulation. A case in point is miR-381-3p, but its mechanism in glioma is unclear yet. In this work, we confirmed that overexpressed miR-381-3p repressed biological functions of glioma cells. Additionally, we also discovered that upregulated anthrax toxin receptor 1 (ANTXR1) was negatively mediated by miR-381-3p. We further proved that miR-381-3p-targeted ANTXR1 was able to counteract the suppression of miR-381-3p on biological functions of glioma. We concluded that miR-381-3p and ANTXR1 were both important factors in modulating glioma progression. miR-381-3p/ANTXR1 axis is expected to be a molecular target for glioma., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Zhiqiang Dong et al.)

Inflammation and oxidative stress have indispensable roles in the development of acute lung injury (ALI). MicroRNA (miRNA/miR)‑351‑5p was initially identified as a myogenesis‑associated miRNA; however, its role in lipopolysaccharide (LPS)‑induced ALI remains unclear. The aim of the present study was to investigate the role and potential mechanisms of miR‑351‑5p in ALI. ALI was induced through a single intratracheal injection of LPS for 12 h, and miR‑351‑5p agomir, antagomir or their corresponding negative controls were injected into the tail vein before LPS stimulation. Compound C, 2',5'‑dideoxyadenosine and H89 were used to inhibit AMP‑activated protein kinase (AMPK), adenylate cyclase and protein kinase A (PKA), respectively. miR‑351‑5p levels in the lungs were significantly increased in response to LPS injection. miR‑351‑5p antagomir alleviated, while miR‑351‑5p agomir aggravated LPS‑induced oxidative stress and inflammation in the lungs. The present results also demonstrated that miR‑351‑5p antagomir attenuated LPS‑induced ALI via activating AMPK, and that the cAMP/PKA axis was required for the activation of AMPK by the miR‑351‑5p antagomir. In conclusion, the present study indicated that miR‑351‑5p aggravated LPS‑induced ALI via inhibiting AMPK, suggesting that targeting miR‑351‑5p may help to develop efficient therapeutic approaches for treating ALI.

Objectives: Acute lung injury (ALI) is a devastating lung disease characterized by uncontrolled pulmonary inflammation and oxidative stress. Currently, no effective therapeutic strategies are available for ALI and its prognosis remains poor. The present study aims to investigate the role and potential mechanism of microRNA-30d-5p (miR-30d-5p) in the progression of ALI., Methods: Mice were intravenously treated with miR-30d-5p agomir, antagomir or their respective controls for 3 consecutive days and then were exposed to a single intratracheal injection of lipopolysaccharide (LPS) for 12 h at a dosage of 5 mg/kg to induce ALI. To inhibit adenosine monophosphate-activated protein kinase α (AMPKα) or phosphodiesterase 4 D (PDE4D), compound C (CpC) and rolipram were used., Results: miR-30d-5p expression in the lungs was significantly inhibited by LPS treatment. miR-30d-5p agomir significantly alleviated, while miR-30d-5p antagomir aggravated pulmonary inflammation, oxidative damage, and dysfunction in ALI mice. Besides, we found that miR-30d-5p agomir ameliorated LPS-induced ALI via activating AMPKα and that the inhibition of AMPKα by CpC completely abolished these beneficial effects of miR-30d-5p agomir. Further findings validated that PDE4D downregulation was required for the activation of AMPKα by miR-30d-5p agomir., Conclusion: miR-30d-5p ameliorates LPS-induced ALI via activating AMPKα and it is a valuable therapeutic candidate in the treatment of ALI.

Purpose: Lenvatinib is a long-awaited alternative to Sorafenib for first-line targeted therapy of patients with advanced hepatocellular carcinoma (HCC). However, resistance to Lenvatinib results in tumor progression and has become a major obstacle to improving the prognosis of HCC patients. Exploring the mechanisms underlying Lenvatinib resistance is considered essential for the treatment of advanced HCC., Methods: Lenvatinib resistant HCC (LR-HCC) cells were generated and potential long non-coding RNAs (Lnc-RNAs) upregulated in LR-HCC cells were identified by RNA sequencing. The effects of upregulated Lnc-RNAs were evaluated in vitro in cell models and in vivo in experimental animals using quantitative cell viability and apoptosis assays., Results: We found that Lnc-RNA MT1JP (MT1JP) was upregulated in LR-HCC cells and inhibited the apoptosis signaling pathway. In addition, we found that sponging of microRNA-24-3p by MT1JP released Bcl-2 like 2 (BCL2L2), an anti-apoptotic protein, thereby forming a positive-feedback loop. The role of this feedback loop was validated using rescue assays. Additionally, we found that upregulation of MT1JP and BCL2L2 impaired the sensitivity of HCC cells to Lenvatinib both vitro and vivo., Conclusions: Our results suggest a novel molecular feedback loop between MT1JP and apoptosis signaling in Lenvatinib sensitive HCC cells., (© 2021. The Author(s).)

Background: Circular RNA (circRNA) has been shown to be associated with osteoarthritis (OA) progression. Circ_0116061 has been found to be highly expressed in OA cartilage tissues, but its role and mechanism in OA progression remain unclear., Methods: Expression levels of circ_0116061, microRNA (miR)-200b-5p, and Smad ubiquitin regulatory factor 2 (SMURF2) were detected using quantitative real-time PCR. The proliferation and apoptosis of cells were measured using cell counting kit 8 (CCK8) assay, colony formation assay, and flow cytometry. Furthermore, the protein levels of proliferation-related marker, apoptosis-related markers, inflammatory factors, and SMURF2 were tested using western blot (WB) analysis. In addition, the interaction between miR-200b-3p and circ_0116061 or SMURF2 was examined using dual-luciferase reporter assay and biotin-labeled RNA pull-down assay., Results: Circ_0116061 and SMURF2 were highly expressed, and miR-200b-3p was lowly expressed in OA cartilage tissues. Knockdown of circ_0116061 could promote the proliferation and inhibit the apoptosis and inflammation of OA chondrocytes. MiR-200b-3p could be sponged by circ_0116061, and its inhibitor could reverse the regulation of circ_0116061 silencing on the biological functions of OA chondrocytes. SMURF2 was a target of miR-200b-3p, and its expression was positively regulated by circ_0116061. Silencing of SMURF2 also could enhance the proliferation and suppress the apoptosis and inflammation of OA chondrocytes. Furthermore, the regulation of circ_0116061 silencing on the biological functions of OA chondrocytes also could be reversed by SMURF2 overexpression., Conclusion: Our data showed that circ_0116061 might regulate the miR-200b-3p/SMURF2 axis to promote the progression of OA.

Background: Circular RNAs (circRNAs) are associated with rheumatoid arthritis (RA) development. The purpose of this study is to explore the function and mechanism of circRNA fragile mental retardation 2 (circ-AFF2) in the processes of rheumatoid arthritis fibroblast-like synoviocytes (RAFLSs)., Methods: Circ-AFF2, microRNA (miR)-650, and 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) levels were determined in synovial tissues of RA and RAFLSs by quantitative reverse transcription polymerase chain reaction or Western blotting. Cell proliferation, inflammatory response, apoptosis, caspase3 activity, migration, invasion, and epithelial-mesenchymal transition (EMT) were investigated using Cell Counting Kit-8 (CCK-8), enzyme-linked immunosorbent assay (ELISA), flow cytometry, Transwell, and Western blotting analyses. Dual-luciferase reporter, RNA immunoprecipitation (RIP), and pull-down assays were performed to assess the binding relationship., Results: Circ-AFF2 expression level was enhanced in synovial tissues of RA and RAFLSs. Circ-AFF2 overexpression facilitated cell proliferation, inflammatory response, migration, invasion, and EMT and repressed apoptosis in RAFLSs. Circ-AFF2 downregulation played an opposite role. Circ-AFF2 targeted miR-650, and miR-650 downregulation reversed the effect of circ-AFF2 interference on RAFLS processes. CNP was targeted by miR-650, and circ-AFF2 increased CNP expression by regulating miR-650. MiR-650 overexpression constrained cell proliferation, inflammatory response, migration, invasion, and EMT and contributed to apoptosis by decreasing CNP in RAFLSs., Conclusion: Circ-AFF2 promoted proliferation, inflammatory response, migration, and invasion of RAFLSs by modulating the miR-650/CNP axis.

Dysregulation of microRNA contributes to multiple tumorigenic processes. Although downregulation of miR-199a-3p has been shown in many cancers, its effects on esophageal squamous cell carcinoma (ESCC) and the regulatory mechanism are still obscure. Here, we aim to evaluate the biological function and underlying mechanisms of miR-199a-3p in ESCC as well as its value to clinical treatment of ESCC. We first analyzed expression of miR-199a-3p in esophageal cancer by bioinformatic analysis and found that there were different opinions about expression of miR-199a-3p in esophageal cancer, and the following qRT-PCR assay demonstrated which was markedly downregulated in ESCC cells. Next, we increased the expression of miR-199a-3p in ESCC cells using miR-199a-3p mimics and demonstrated that overexpression of miR-199a-3p significantly inhibited cell proliferation, migration and invasion, as well as induced cell cycle retard and promoted apoptosis in ESCC. Furthermore, we explored the functional targets of miR-199a-3p and identified that overexpression of miR-199a-3p inhibited mTOR/p70S6K pathway, but stimulated PI3K/Akt pathway. Finally, we demonstrated that overexpression of miR-199a-3p enhanced proliferation-inhibiting effects of MK2206, an inhibitor of Akt, to ESCC cells, which might be related that MK2206 eliminated the activation of miR-199a-3p to p-Akt. These findings discover that miR-199a-3p might participate in the carcinogenesis process of ESCC, which provides a new insight for treatment of ESCC., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Gastric cancer (GC) is one of the most commonly diagnosed malignancy worldwide. DLX6 antisense RNA 1 (DLX6-AS1) is a long noncoding RNA (lncRNA) that exhibits oncogenic effects on multiple human carcinomas., Aims: This study aimed to investigate the regulatory effect of DLX6-AS1 in GC progression., Methods: The expression of DLX6-AS1 in GC tissues and cell lines was examined. The cell viability, number of clones, and apoptosis, aerobic glycolysis, and mitochondrial respiration was assessed. The effect of DLX6-AS1 on tumor growth in nude mice was also evaluated., Results: DLX6-AS1 was overexpressed in GC tissues and cell lines. DLX6-AS1 knockdown by short hairpin RNA (shRNA) significantly inhibited cell viability and colony formation, and induced apoptosis. DLX6-AS1 silencing impaired aerobic glycolysis but stimulated mitochondrial respiration in GC cells. miR-4290 was confirmed as a downstream target of DLX6-AS1, and their expression levels were inversely correlated. GC cells expressing sh-DLX6-AS1 showed significantly lower level of 3-phosphoinositide-dependent protein kinase 1 (PDK1), a target of miR-4290, compared to cells expressing control shRNA. In addition, the suppressed GC cell malignancy upon DLX6-AS1 knockdown could be prominently reversed by PDK1 overexpression. Meanwhile, PDK1 overexpression enhanced aerobic glycolysis but repressed mitochondrial respiration under sh-DLX6-AS1 treatment. Furthermore, DLX6-AS1 knockdown significantly delayed the tumor growth in a mouse xenograft model inoculated with GC cells., Conclusions: LncRNA DLX6-AS1 regulated tumor growth and aerobic glycolysis in GC by targeting miR-4290 and PDK1, suggesting DLX6-AS1 might serve as a novel potential therapeutic target for GC treatment from bench to clinic.

Since most variants that impact polygenic disease phenotypes localize to non-coding genomic regions, understanding the consequences of regulatory element variants will advance understanding of human disease mechanisms. Here, we report that the systemic lupus erythematosus (SLE) risk variant rs2431697 as likely causal for SLE through disruption of a regulatory element, modulating miR-146a expression. Using epigenomic analysis, genome-editing and 3D chromatin structure analysis, we show that rs2431697 tags a cell-type dependent distal enhancer specific for miR-146a that physically interacts with the miR-146a promoter. NF-kB binds the disease protective allele in a sequence-specific manner, increasing expression of this immunoregulatory microRNA. Finally, CRISPR activation-based modulation of this enhancer in the PBMCs of SLE patients attenuates type I interferon pathway activation by increasing miR-146a expression. Our work provides a strategy to define non-coding RNA functional regulatory elements using disease-associated variants and provides mechanistic links between autoimmune disease risk genetic variation and disease etiology.

Introduction: LincRNA-p21 is predicted to interact with miR-449a, which plays a protective role in cisplatin-induced acute kidney injury (CIA)., Objective: This study aimed to analyze the involvement of lincRNA-p21 in breast cancer patients with CIA., Methods: Levels of lincRNA-p21 in plasma from CIA, triple negative breast cancer, and control groups were measured by performing RT-qPCR. The potential interaction between lincRNA-p21 and miR-449a was first predicted by RT-qPCR. The relationship between lincRNA-p21 and miR-449a was analyzed by overexpression experiment., Results: We found that lincRNA-p21 is downregulated in CIA. Dual luciferase activity assay showed that lincRNA-p21 and miR-449a can interact with each other, while overexpression of lincRNA-p21 and miR-449a failed to affect the expression of each other. In human renal proximal tubular epithelial cells (HRPTEpCs), cisplatin led to the upregulated miR-449a but downregulated lincRNA-p21. Interestingly, lincRNA-p21 overexpression led to reduced enhancing effects of miR-449a on the cisplatin-induced apoptosis of HRPTEpCs., Conclusion: Therefore, lincRNA-p21 is downregulated in CIA and may sponge miR-449a to inhibit cisplatin-induced apoptosis of HRPTEpCs., (© 2021 The Author(s). Published by S. Karger AG, Basel.)

The function of a new long non-coding RNA GAS6-AS2 in non-small cell lung cancer (NSCLC) is not fully understood. In this study, GAS6-AS2 was identified, and its roles as well as mechanisms in regulating proliferation of NSCLCs cells were investigated. qRT-PCR was used to analyze GAS6-AS2, miR-144-3p, and MAPK6 expression. Protein expression was detected by Western blotting. Cell Counting Kit-8 (CCK8) assay was used to examine the cell proliferation ability. The interaction between GAS6-AS2 and miR-144-3p was confirmed by dual-luciferase reporter assay and RNA pull down assay. A xenograft model was constructed to monitor the mice NSCLC tumor growth in vivo . GAS6-AS2 was up-regulated, while miR-144-3p was suppressed in NSCLC cells compared with normal lung cells. GAS6-AS2 suppression could inhibit the progression of NSCLC cells, and miR-144-3p could attenuate the effect. GAS6-AS2 could function as a competitive endogenous RNA (ceRNA) via direct sponging miR-144-3p-3p, which further regulating the expression of MAPK6. The knockdown of GAS6-AS2 could greatly suppress the tumor growth of NSCLC in vivo . GAS6-AS2 up-regulated MAPK6 by sponging miR-144-3p in NSCLC tissues and cells. Thus, GAS6-AS2 is an effective therapeutic target in NSCLC.

Background: Zhengdan 958 (Zheng 58 × Chang 7-2), a commercial hybrid that is produced in a large area in China, is the result of the successful use of the heterotic pattern of Reid × Tang-SPT. The jointing stage of maize is the key period from vegetative to reproductive growth, which determines development at later stages and heterosis to a certain degree. MicroRNAs (miRNAs) play vital roles in the regulation of plant development, but how they function in the sixth leaf at the six-leaf (V6) stage to influence jointing stage heterosis is still unclear., Result: Our objective was to study miRNAs in four hybrid combinations developed in accordance with the Reid × Tang-SPT pattern, Zhengdan 958, Anyu 5 (Ye 478 × Chang 7-2), Ye 478 × Huangzaosi, Zheng 58 × Huangzaosi, and their parental inbred lines to explore the mechanism related to heterosis. A total of 234 miRNAs were identified in the sixth leaf at the V6 stage, and 85 miRNAs were differentially expressed between the hybrid combinations and their parental inbred lines. Most of the differentially expressed miRNAs were non-additively expressed, which indicates that miRNAs may participate in heterosis at the jointing stage. miR164, miR1432 and miR528 families were repressed in the four hybrid combinations, and some miRNAs, such as miR156, miR399, and miR395 families, exhibited different expression trends in different hybrid combinations, which may result in varying effects on the heterosis regulatory mechanism., Conclusions: The potential targets of the identified miRNAs are related to photosynthesis, the response to plant hormones, and nutrient use. Different hybrid combinations employ different mature miRNAs of the same miRNA family and exhibit different expression trends that may result in enhanced or repressed gene expression to regulate heterosis. Taken together, our results reveal a miRNA-mediated network that plays a key role in jointing stage heterosis via posttranscriptional regulation.

Gastric cancer (GC) is the most common cancer throughout the world. Despite advances of the treatments, detailed oncogenic mechanisms are largely unknown. In our previous study, we investigated microRNA (miR) expression profiles in human GC using miR microarrays. We found miR-192/215 were upregulated in GC tissues. Then gene microarray was implemented to discover the targets of miR-192/215. We compared the expression profile of BGC823 cells transfected with miR-192/215 inhibitors, and HFE145 cells transfected with miR-192/-215 mimics, respectively. SET8 was identified as a proposed target based on the expression change of more than twofold. SET8 belongs to the SET domain-containing methyltransferase family and specifically catalyzes monomethylation of H4K20me. It is involved in diverse functions in tumorigenesis and metastasis. Therefore, we focused on the contributions of miR-192/215/SET8 axis to the development of GC. In this study, we observe that functionally, SET8 regulated by miR-192/215 is involved in GC-related biological activities. SET8 is also found to trigger oncogene-induced senescence (OIS) in GC in vivo and in vitro, which is dependent on the DDR (DNA damage response) and p53. Our findings reveal that SET8 functions as a negative regulator of metastasis via the OIS-signaling pathway. Taken together, we investigated the functional significance, molecular mechanisms, and clinical impact of miR-192/215/SET8/p53 in GC.

It is well known that some pathogenic cells have enhanced glycolysis; the regulatory network leading to increased glycolysis are not well characterized. In this study, we show that CNS-infiltrated pathogenic T H 17 cells from diseased mice specifically upregulate glycolytic pathway genes compared with homeostatic intestinal T H 17 cells. Bioenergetic assay and metabolomics analyses indicate that in vitro-derived pathogenic T H 17 cells are highly glycolytic compared with nonpathogenic T H 17 cells. Chromatin landscape analyses demonstrate T H 17 cells in vivo that show distinct chromatin states, and pathogenic T H 17 cells show enhanced chromatin accessibility at glycolytic genes with NF-κB binding sites. Mechanistic studies reveal that miR-21 targets the E3 ubiquitin ligase Peli1 -c-Rel pathway to promote glucose metabolism of pathogenic T H 17 cells. Therapeutic targeting c-Rel-mediated glycolysis in pathogenic T H 17 cells represses autoimmune diseases. These findings extend our understanding of the regulation T H 17 cell glycolysis in vivo and provide insights for future therapeutic intervention to T H 17 cell-mediated autoimmune diseases., (Copyright © 2020 by The American Association of Immunologists, Inc.)

Multiple sclerosis is a chronic autoimmune disease driven by pathogenic Th17 cells. In this study, we dissected the role of miR - 22 in pathogenic Th17 cells by autoantigen-specific disease models. We first showed that miR-22 was upregulated in peripheral lymphoid organs and spinal cords of mice developed autoimmune encephalomyelitis. Although miR - 22 was upregulated in multiple Th cell subsets, it was dispensable for Th cell differentiation in vitro. Whereas miR-22 -/- mice exhibited milder symptoms of disease in an active experimental autoimmune encephalomyelitis model, adoptive transfer of miR-22 -/- 2D2 Th17 cells into naive recipient mice promoted higher disease incidence and severity compared with mice transferred with control 2D2 Th17 cells. Global transcriptional analysis of miR-22- deficient pathogenic Th17 cells revealed upregulated genes in phosphatase and tensin homologue (PTEN)-mediated pathways, and Pten was further identified as one of its potential targets. Therefore, we identified that Th17 cell-intrinsic miR-22 could protect mice from autoimmunity by targeting PTEN-regulated pathways., (Copyright © 2020 The Authors.)

The development of chemotherapy resistance significantly impairs the efficiency of chemotherapy, but the underlying mechanisms of chemotherapy resistance in gastric cancer (GC) are complicated and still need to be further explored. Here, we aimed to reveal the effects of miR-4290/PDK1 (pyruvate dehydrogenase kinase 1) axis on chemotherapy resistance of GC in vitro. The expression patterns of miR-4290 in GC tissues and cell lines were determined by real-time quantitative PCR. Kaplan-Meier was used to assess the relationship between miR-4290 expression levels and patients' overall survival. CCK-8 and flow cytometry technologies were applied to detect cell proliferation and apoptosis. The luciferase gene reporter assay was used to evaluate the interaction between miR-4290 and PDK1. miR-4290 was lowly expressed in GC tissues and cell lines, which was closely associated with the shorter overall survival of GC patients. miR-4290 mimics significantly inhibited cell proliferation and induced cell apoptosis, as well as induced a significant reduction in the expression of PDK1. Moreover, miR-4290 significantly inhibited glycolysis and decreased the IC50 value to cisplatin in SGC7901 cells, whereas these effects were abolished and cell apoptosis was promoted when PDK1 was overexpressed. In conclusion, this study revealed that miR-4290 suppressed PDK1-mediated glycolysis to enhance the sensitivity of GC cells to cisplatin.

The roles of microRNAs (miRNAs) in liver cancer have attracted much attention in recent years. In this study, we demonstrate that miR-520b is downregulated in MHCC-97H cells, a liver cancer cell line with high potential of metastasis, compared with MHCC-97L cells which has a low potential of metastasis. Furthermore, the enhanced expression of miR-520b could inhibit liver cancer cell migration, while silencing its expression resulted in increased migration. Mixed lineage kinase 3 (MLK3) was identified as a direct and functional new target of miR-520b. This regulation was also confirmed by luciferase reporter assays. In addition, our results showed that overexpression of the MLK3 expression partially reversed the effect of miR-520b on liver cancer cell migration, indicating that MLK3 contributes to the migration in liver cancer. The newly identified miR-520b/MLK3 axis partially elucidates the molecular mechanism of liver cancer cell migration and represents a new potential therapeutic target for liver cancer treatment., Competing Interests: The authors have declared that no competing interests exist.

Background: MicroRNAs (miRNAs) play crucial roles in the regulation of plant development and growth, but little information is available concerning their roles during grain development under different nitrogen (N) application levels. Our objective was to identify miRNAs related to the regulation of grain characteristics and the response to different N fertilizer conditions., Results: A total of 79 miRNAs (46 known and 33 novel miRNAs) were identified that showed significant differential expression during grain development under both high nitrogen (HN) and low nitrogen (LN) treatments. The miRNAs that were significantly upregulated early in grain development target genes involved mainly in cell differentiation, auxin-activated signaling, and transcription, which may be associated with grain size; miRNAs abundant in the middle and later stages target genes mainly involved in carbohydrate and nitrogen metabolism, transport, and kinase activity and may be associated with grain filling. Additionally, we identified 50 miRNAs (22 known and 28 novel miRNAs), of which 11, 9, and 39 were differentially expressed between the HN and LN libraries at 7, 17, and 27 days after anthesis (DAA). The miRNAs that were differentially expressed in response to nitrogen conditions target genes involved mainly in carbohydrate and nitrogen metabolism, the defense response, and transport as well as genes that encode ubiquitin ligase. Only one novel miRNA (PC-5p-2614_215) was significantly upregulated in response to LN treatment at all three stages, and 21 miRNAs showed significant differential expression between HN and LN conditions only at 27 DAA. We therefore propose a model for target gene regulation by miRNAs during grain development with N-responsive patterns., Conclusions: The potential targets of the identified miRNAs are related to various biological processes, such as carbohydrate/nitrogen metabolism, transcription, cellular differentiation, transport, and defense. Our results indicate that miRNA-mediated networks, via posttranscriptional regulation, play crucial roles in grain development and the N response, which determine wheat grain weight and quality. Our study provides useful information for future research of regulatory mechanisms that focus on improving grain yield and quality.

Long non‑coding (lnc)RNA sprouty receptor tyrosine kinase signalling antagonist 4‑intronic transcript 1 (SPRY4‑IT1) has been demonstrated to serve a critical role in the tumorigenesis of osteosarcoma (OS); however, the specific underlying mechanism remains unclear. The aim of the present study was to examine the interactions between SPRY4‑IT1 and its downstream effectors, to determine if any of the interactions contributed to SPRY4‑IT1‑mediated proliferation, migration and invasion in cancer cells. A signalling cascade which involved SPRY4‑IT1, miR‑101 and zinc finger E‑box‑binding homeoboxes (ZEBs) was examined in the present study. Intracellular SPRY4‑IT1 and miR‑101 expression levels were altered through transfection to assess their effect on proliferation, cell cycle progression, survival, migration and invasion. A dual‑luciferase assay was utilized to determine the association between SPRY4‑IT1/miR‑101 and ZEBs/miR‑101 and nude mouse xenograft experiments were performed to determine the effect of SPRY4‑IT1 in vivo. The results indicated that the SPRY4‑IT1 levels were negatively associated with miR‑101 expression levels in OS cells, an association which was not observed in the normal osteoblast cells. SPRY4‑IT1 knockdown or miR‑101 overexpression reduced proliferation, cell cycle progression, survival, migration and invasion of MG‑63 and U2OS cells. SPRY4‑IT1 knockdown was accompanied by increased expression of miR‑101 and E‑cadherin levels, as well as decreased expression levels of ZEB1/2 and other epithelial‑mesenchymal transition‑associated proteins. Simultaneous knockdown of SPRY4‑IT1 and inhibition of miR‑101 partially reversed the anti‑tumour effects of SPRY4‑IT1 inhibition in vitro. Consistent with these findings, short hairpin RNA targeting SPRY4‑IT1 also hindered xenograft tumour growth and altered the levels of miR‑101, ZEB1/2 and E‑cadherin in vivo. Dual‑luciferase reporter assays demonstrated that SPRY4‑IT1 may have regulated the expression of ZEB1 and ZEB2 by sponging miR‑101. In conclusion, SPRY4‑IT1 inhibition increased miR‑101 levels, resulting in downregulation of ZEB1/2 expression and thus exerting anti‑tumour effects in OS.

To uncover the biological function of miRNA-217 in the progression of bladder cancer and the underlying mechanism. Potential miRNAs binding KMT2D were predicted through online bioinformatics. Their expression levels in bladder cancer tissues and adjacent ones were determined. Through Pearson correlation analysis and survival analysis, the most potential miRNA candidate (miRNA-217) that targets and regulates KMT2D in bladder cancer was selected. Subsequently, expression levels of miRNA-217 and KMT2D in non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC) were detected. MiRNA-217 level in bladder cancer cell lines was determined as well. The interaction between KMT2D and miRNA-217 was verified by dual-luciferase reporter gene assay. Finally, regulatory effect of miRNA-217 on viability and migration in T24 and UMUC-3 cells were investigated. Five potential candidates that were upstream genes binding KMT2D were searched by bioinformatics. Among them, miRNA-217 was remarkably upregulated in bladder cancer tissues and closely linked to poor prognosis of affected patients. Moreover, dual-luciferase reporter gene assay verified the interaction between miRNA-217 and KMT2D. MiRNA-217 was able to downregulate mRNA and protein levels of KMT2D. Furthermore, knockdown of miRNA-217 attenuated viability and migration in bladder cancer cells. MiRNA-217 accelerates proliferative and migratory abilities in bladder cancer via inhibiting the level of tumor suppressor KMT2D, thereafter leading to the poor prognosis in bladder cancer patients., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: The aim of this study was to elucidate the potential function of microRNA-488-3p (miRNA-488-3p) in the pathogenesis of acute myocardial infarction (AMI)., Materials and Methods: AMI mice constructed by ligation of the anterior descending coronary artery (LAD) were administrated with miRNA-488-3p mimics or negative control, respectively. Infarct size and risk region of AMI mice were determined by triphenyltetrazolium chloride (TTC) staining. The serum level of lactate dehydrogenase (LDH) release in mice was detected by enzyme-linked immunosorbent assay (ELISA). Subsequently, primary cardiomyocytes were isolated from AMI mice administrated with miRNA-488-3p mimics or negative control. LDH release in both hypoxia-preconditioning primary cardiomyocytes and MCM cells was detected. Dual-Luciferase reporter gene assay was used to verify the potential target of miRNA-488-3p. Furthermore, the regulatory effects of miRNA-488-3p and its target ZNF791 on AMI-induced cardiomyocyte apoptosis were evaluated., Results: MiRNA-488-3p was lowly expressed in AMI mice. Meanwhile, miRNA-488-3p expression decreased in hypoxia-preconditioning primary cardiomyocytes or MCM cells in a time-dependent manner. AMI mice overexpressing miRNA-488-3p showed significantly smaller infarct size and risk region, as well as lower LHD release in serum. Overexpression of miRNA-488-3p markedly down-regulated the protein level of caspase3 in MCM cells. ZNF791 was predicted as the direct target of miRNA-488-3p, which was negatively regulated by miRNA-488-3p. Overexpression of ZNF791 reversed the protective role of miRNA-488-3p in AMI-induced cardiomyocyte apoptosis., Conclusions: MiRNA-488-3p is down-regulated in AMI mice, which alleviates AMI-induced cardiomyocyte apoptosis via down-regulating ZNF791.

Notoginsenoside R1 (NG-R1) is a major component of Panax notoginseng, which has been used clinically for the treatment of diabetic nephropathy for centuries in China. This study aimed to reveal the functional impacts and the underlying mechanisms of NG-R1 on oxygen-glucose deprivation (OGD)-injured cardiomyocytes. Rat cardiomyocyte line H9c2 and primary cardiomyocytes were subjected to OGD with or without NG-R1 treatment. The expression levels of miR-21 and phosphatase and tensin homolog (PTEN) in the cell were altered by microRNA, vector or short-hairpin RNA transfections. Thereafter, changes in cell viability, apoptosis, and PI3K/AKT signaling were monitored. NG-R1 with low concentrations had no impact on H9c2 cells viability, but 80 μM of NG-R1 significantly reduced cell viability. NG-R1 (20 μM) protected H9c2 cells and primary cardiomyocytes against OGD-induced cell damage, as cell viability was increased, apoptotic cell rate was reduced, and Bax, cleaved caspase-3 and -9 were downregulated by addition of NG-R1. MiR-21 was low expressed in response to OGD exposure, while was highly expressed by NG-R1 treatment. PTEN was a direct target of miR-21. More interestingly, OGD-induced cell damage could be recovered by miR-21 overexpression or PTEN silence. Furthermore, PTEN silence recovered OGD-blocked PI3K/AKT signaling pathway. To conclude, this study demonstrated that NG-R1 exerted remarkable benefits in reduction of OGD-induced cardiomyocyte loss. The cardioprotective actions of NG-R1 possibly via upregulation of miR-21, repressing the expression of miR-21's target PTEN and thereby preventing the blockage of PI3K/AKT signaling pathway., (© 2018 Wiley Periodicals, Inc.)

Less than a century ago, gastric cancer (GC) was the most common cancer throughout the world. Despite advances in surgical, chemotherapeutic, and radiotherapeutic treatment, GC remains the number 3 cancer killer worldwide. This fact highlights the need for better diagnostic biomarkers and more effective therapeutic targets. RAB11-FIP2, a member of the Rab11 family of interacting proteins, exhibits potential tumor suppressor function. However, involvement of RAB11-FIP2 in gastric carcinogenesis is yet to be elucidated. In this study, we demonstrated that RAB11-FIP2 was downregulated in GC tissues and constituted a target of the known onco-miRs, miR-192/215. We also showed that functionally, Rab11-FIP2 regulation by miR-192/215 is involved in GC-related biological activities. Finally, RAB11-FIP2 inhibition by miR-192/215 affected the establishment of cell polarity and tight junction formation in GC cells. In summary, this miR-192/215-Rab11-FIP2 axis appears to represent a new molecular mechanism underlying GC progression, while supplying a promising avenue of further research into diagnosis and therapy of GC.

Diabetic cardiomyopathy (DCM) is defined as ventricular dysfunction occurring independently of a recognized cause such as hypertension or coronary artery disease. Liver X receptor α (LXRα), a subtype of ligand-activated transcription factors LXRs, has been considered as a potential pharmacological target in the pathogenesis of cardiovascular and metabolic diseases. However, the potential mechanism of how LXRα is regulated in cardiomyocytes is still unclear. This study investigated the effect of activating LXRα with GW3965 on cardiomyocyte apoptosis and its upstream regulator in glucose-induced H9C2 cells. Our data indicated that GW3965 up-regulated the expression of LXRα, inhibited cardiomyocyte apoptosis, and altered the apoptosis-related proteins in glucose-induced H9C2 cells. In addition, GW3965 restored the mitochondrial membrane potential level and decreased the ROS production induced by glucose. Moreover, LXRα was confirmed as a direct target of microRNA-1 (miR-1) that was involved in cardiomyocyte apoptosis of DCM, and overexpression of miR-1 abrogated the inhibiting effect of GW3965 on glucose-induced apoptosis in H9C2 cells. This study highlights an important role of LXRα in the development of DCM and brings new insights into the complex mechanisms involved in the pathogenesis of DCM.

Background: MicroRNAs (miRNAs) are important regulators involved in diverse physiological and pathological processes including cancer. SUMO (small ubiquitin-like modifier) is a reversible protein modifier. We recently found that SUMOylation of TARBP2 and DGCR8 is involved in the regulation of the miRNA pathway. KHSRP is a single stranded nucleic acid binding protein with roles in transcription and mRNA decay, and it is also a component of the Drosha-DGCR8 complex promoting the miRNA biogenesis., Methods: The in vivo SUMOylation assay using the Ni 2+ -NTA affinity pulldown or immunoprecipitation (IP) and the in vitro E.coli-based SUMOylation assay were used to analyze SUMOylation of KHSRP. Nuclear/Cytosol fractionation assay and immunofluorescent staining were used to observe the localization of KHSRP. High-throughput miRNA sequencing, quantantive RT-PCR and RNA immunoprecipitation assay (RIP) were employed to determine the effects of KHSRP SUMO1 modification on the miRNA biogenesis. The soft-agar colony formation, migration, vasculogenic mimicry (VM) and three-dimensional (3D) cell culture assays were performed to detect the phenotypes of tumor cells in vitro, and the xenograft tumor model in mice was conducted to verify that SUMO1 modification of KHSRP regulated tumorigenesis in vivo., Results: KHSRP is modified by SUMO1 at the major site K87, and this modification can be increased upon the microenvironmental hypoxia while reduced by the treatment with growth factors. SUMO1 modification of KHSRP inhibits its interaction with the pri-miRNA/Drosha-DGCR8 complex and probably increases its translocation from the nucleus to the cytoplasm. Consequently, SUMO1 modification of KHSRP impairs the processing step of pre-miRNAs from pri-miRNAs which especially harbor short G-rich stretches in their terminal loops (TL), resulting in the downregulation of a subset of TL-G-Rich miRNAs such as let-7 family and consequential tumorigenesis., Conclusions: Our data demonstrate how the miRNA biogenesis pathway is connected to tumorigenesis and cancer progression through the reversible SUMO1 modification of KHSRP.

Objective: Recent studies have identified Engrailed-2 (EN-2), a homeobox-containing transcription factor, as a candidate oncogene in prostate cancer (PC). Therapeutic targeting on EN-2, however, is limited because the mechanism underlying EN-2 overexpression in prostatic cancer cells is unknown. This study was to investigate the potential regulatory role of miR-33a on EN-2 expression and explore this signaling axis in ability of prostate cancer survival and metastasis., Methods: The relative expression of miR-33a and EN-2 in paired prostate cancer tissue and adjacent normal tissue as well as in prostate cancer cell lines, PC3 and DU145, was determined using quantitative real-time PCR or western blot, respectively. Cells survival, migration and invasion were evaluated by assays of MTT, TUNEL and Boyden chamber assays, respectively. Direct regulation of EN-2 by miR-33a was examined by luciferase reporter assay., Results: The data showed that miR-33a was upregulated and EN-2 was downregulated in both prostate cancer tissue and prostate cancer cells. miR-33a overexpression suppresses prostate cancer cell survival and metastasis. miR-33a can directly act on EN-2 expression by binding to 3'UTR of its mRNA. Also, miR-33a negatively regulated EN-2 mRNA and protein expression. In pcDNA-EN-2 and miR-33a mimic co-transfected PC3 and DU145 cells, EN-2 overexpression reverses the anti-cell survival and metastasis actions of miR-33a overexpression. The pivotal role of miR-33a in inhibiting prostate tumor growth was confirmed in xenograft models of prostate cancer., Conclusion: Our data suggest that the functional interaction of miR-33a and EN-2 is involved in tumorigenesis of prostate cancer. Also in this process EN-2 serves as a negative responder for miR-33a.

Many viruses encode microRNAs (miRNAs) that are small non-coding single-stranded RNAs which play critical roles in virus-host interactions. Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most economically impactful viruses in the swine industry. The present study sought to determine whether PRRSV encodes miRNAs that could regulate PRRSV replication. Four viral small RNAs (vsRNAs) were mapped to the stem-loop structures in the ORF1a, ORF1b and GP2a regions of the PRRSV genome by bioinformatics prediction and experimental verification. Of these, the structures with the lowest minimum free energy (MFE) values predicted for PRRSV-vsRNA1 corresponded to typical stem-loop, hairpin structures. Inhibition of PRRSV-vsRNA1 function led to significant increases in viral replication. Transfection with PRRSV-vsRNA1 mimics significantly inhibited PRRSV replication in primary porcine alveolar macrophages (PAMs). The time-dependent increase in the abundance of PRRSV-vsRNA1 mirrored the gradual upregulation of PRRSV RNA expression. Knockdown of proteins associated with cellular miRNA biogenesis demonstrated that Drosha and Argonaute (Ago2) are involved in PRRSV-vsRNA1 biogenesis. Moreover, PRRSV-vsRNA1 bound specifically to the nonstructural protein 2 (NSP2)-coding sequence of PRRSV genome RNA. Collectively, the results reveal that PRRSV encodes a functional PRRSV-vsRNA1 which auto-regulates PRRSV replication by directly targeting and suppressing viral NSP2 gene expression. These findings not only provide new insights into the mechanism of the pathogenesis of PRRSV, but also explore a potential avenue for controlling PRRSV infection using viral small RNAs.

Objective: Precancerous lesion, a well-established histopathologically premalignant tissue with the highest risk for tumourigenesis, develops preferentially from activation of DNA damage checkpoint and persistent inflammation. However, little is known about the mechanisms by which precancerous lesions are initiated and their physiological significance., Design: Laser capture microdissection was used to acquire matched normal liver, precancerous lesion and tumour tissues. miR-484(-/-), Ifnar1(-/-) and Tgfbr2(△hep) mice were employed to determine the critical role of the interferon (IFN)-microRNA pathway in precancerous lesion formation and tumourigenesis. RNA immunoprecipitation (RIP), pull-down and chromatin immunoprecipitation (ChIP) assays were applied to explore the underlying mechanisms., Results: miR-484 is highly expressed in over 88% liver samples clinically. DEN-induced precancerous lesions and hepatocellular carcinoma were dramatically impaired in miR-484(-/-) mice. Mechanistically, ectopic expression of miR-484 initiates tumourigenesis and cell malignant transformation through synergistic activation of the transforming growth factor-β/Gli and nuclear factor-κB/type I IFN pathways. Specific acetylation of H3K27 is indispensable for basal IFN-induced continuous transcription of miR-484 and cell transformation. Convincingly, formation of precancerous lesions were significantly attenuated in both Tgfbr2(△hep) and Ifnar1(-/-) mice., Conclusions: These findings demonstrate a new protumourigenic axis involving type I IFN-microRNA signalling, providing a potential therapeutic strategy to manipulate or reverse liver precancerous lesions and tumourigenesis., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Prostate cancer (PCa) is the second leading cause of cancer-related deaths in north American men, and most its related deaths are due to advanced and metastatic PCa. However, the molecular mechanisms underlying PCa progression are still unclear. Here we use a pair of prostate cell lines P69/M12, which have the same genetic background and the highly metastatic cell line M12 is a subline derived from P69, to identify the pathogenesis of PCa. We find that a key miRNA--miR186 is significantly reduced in M12 compared to that in P69. Further, we validate that miR186 is also downregulated in human PCa specimens, most significantly in the metastatic patient specimens. The low miR186 expression is correlated with poor patient survival. Through knockdown or overexpression of miR186 in PCa cell lines, we discover that miR186 strongly inhibits cell motility, invasive, soft-agar colony formation, 3D culture growth and vasculogenic mimicry (VM) formation capacity, as well as the epithelial-to-mesenchymal transition (EMT) process by downregulation of its target Twist1. Moreover, the inverse relationship between the expression levels of miR186 and Twist1 is confirmed in vivo tumor metastasis experiment and clinical specimens. Taken together, our findings demonstrate an important role of miR186/Twist1 axis in the regulation of PCa progression, suggesting a potential application of miR186/Twist1 in PCa treatment., Competing Interests: The authors declare no competing financial interests.

The extremely poor prognosis of patients with symptomatic hepatocellular carcinoma (HCC) diagnosed clinically at advanced stages suggests an urgent need for biomarkers that can be used for prospective surveillance and pre-clinical screening for early presence of pre-malignant lesions and tumors. In a retrospective longitudinal phase 3 biomarker study in seven medical centers of China, time-series and 6 months interval-serum samples were collected from chronic hepatitis B virus infected (CHB) patient cohorts at the pre-malignant or pre-clinical stages (average 6 months prior to clinical diagnosis) and CHB patients that did not develop cancer, and circulating miRNAs measured. A set of serum miRNAs including miR-193a-3p, miR-369-5p, miR-672, miR-429 and let-7i* were identified in pre-clinical HCC patients and have the potential to screen for CHB patients at high risk to develop HCC 6-12 months after miRNAs measurement. These circulating miRNAs combined with the conventional screening tools using α-fetoprotein and ultrasound, may have great promise for the prediction and prevention of HCC in high-risk populations., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Epigenetic modification of miR-429 can manipulate liver T-ICs via targeting the RBBP4/E2F1/Oct4 axis, which might be crucial for hepatocarcinogenesis. However, whether miR-429 plays a role in regulating metastasis of hepatocellular carcinoma is still unclear. Using quantitative methylation analysis and real-time PCR, we have identified the hypomethylated status and upregulation of miR-429 in portal vein metastasis samples in comparison with their matched primary tumor. The ectopic expression of miR-429 dramatically induced the expression of MMP2/7/9 and enhanced HCC migration and invasion in vitro and in vivo in an EMT-independent manner. Both bioinformatics and functional studies elucidated the direct regulation of miR-429 on the 3'UTR of the PTEN gene, which leads to the activation of PI3K/AKT signaling and the nuclear translocation of β-catenin, eventually. Conversely, the knockdown of miR-429 efficiently recovered the expression of PTEN and attenuated PI3K/AKT/β-catenin-mediated cell metastasis. Clinically, the higher expression of miR-429 and nucleus relocation of β-catenin were identified as the adverse prognosis factors for recurrence-free survival (RFS) and overall survival (OS). In summary, our results here defined miR-429 as a key inducer for HCC pathogenesis and metastasis with potential utility for tumor intervention., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)