LncRNA NORAD deficiency alleviates kidney injury in mice and decreases the inflammatory response and apoptosis of lipopolysaccharide-stimulated HK-2 cells via the miR-577/GOLPH3 axis.

BACKGROUND: Long noncoding RNAs (lncRNAs) are significant regulators for sepsis-associated acute kidney injury (AKI). Noncoding RNA activated by DNA damage (NORAD) is highly expressed in the serum of patients with neonatal sepsis. We aimed to reveal the role of NORAD in sepsis-associated AKI. METHODS AND RESULTS: In this study, we established an AKI mouse model by cecal ligation and puncture (CLP) method and used the lipopolysaccharide (LPS)-stimulated HK-2 cells as the in vitro model of AKI. We identified the upregulation of NORAD expression in AKI mice and LPS-treated HK-2 cells. Silencing of NORAD alleviated renal injury by suppressing inflammation and apoptosis in vivo. The influences of NORAD suppression on cell apoptosis and inflammatory response in LPS-treated HK-2 cells were investigated by TUNEL and western blotting. NORAD deficiency inhibited HK-2 cell apoptosis and relieved the inflammation. Moreover, we explored the underlying mechanism by which NORAD regulates HK-2 cells. MiR-577 was verified to directly bind to NORAD, and GOLPH3 was identified as a target downstream miR-577. In addition, GOLPH3 overexpression countervailed the impacts of NORAD downregulation on apoptosis and inflammation in vitro. CONCLUSIONS: Our findings revealed that NORAD knockdown alleviates kidney injury in mice and decreases the inflammatory response and apoptosis of LPS-stimulated HK-2 cells via the miR-577/GOLPH3 axis.

Hsa_circ_0003748 promotes disease progression in rheumatic valvular heart disease by sponging miR-577.

The diagnosis and treatment of rheumatic valvular heart disease (RVHD) require substantial improvements. Studies found that circular RNAs (circRNAs) are involved in the progression of cardiovascular diseases. We screened target hsa_circ_0003748 by circRNA microarrays uploaded to a database. We used fluorescence in situ hybridization to determine the cellular location of hsa_circ_0003748. A dual-luciferase reporter gene assay revealed that has_circ_0003748 might bind the miRNA miR-577. In hVIC cells (an RVHD cell line), Cell Counting Kit-8, Transwell, and flow cytometry assays measured proliferation, migration, and cell cycle and apoptosis, respectively. We found that hsa_circ_0003748 was localized in the cytoplasm; hsa_circ_0003748 promoted the proliferation and migration of hVIC cells, arrested the cell cycle in the G2/M phase, and inhibited apoptosis. These phenomena may result from hsa_circ_0003748 promoting RVHD after sponging miR-577. Bioinformatic analysis revealed that hsa_circ_0003748 might affect RVHD progression by affecting transcription and the MAPK signaling pathway, the Ras signaling pathway, the cAMP signaling pathway, the Rap1 signaling pathway, and other signaling pathways.

MicroRNA-577 aggravates bone loss and bone remodeling by targeting thyroid stimulating hormone receptor in hyperthyroid-associated osteoporosis.

Traditionally, hyperthyroid-associated osteoporosis has been considered to be the result of increased thyroid hormone levels. The pathogenesis of hyperthyroid-associated osteoporosis remains unclear. Thyroid stimulating hormone receptor (TSHR) is closely associated with osteoporosis. Our study aimed to explore the role of TSHR and its upstream microRNA (miRNA) in hyperthyroid-associated osteoporosis. Bioinformatics analysis (starBase and Targetscan) and a wide range of experiments including reverse-transcription quantitative polymerase chain reaction, luciferase reporter, western blot analysis of osteogenic differentiation markers including OSX, OCN, ALP, OPN, and COL1, hematoxylin and eosin staining, Alizarin Red staining assays were used to explore the function and mechanism of TSHR in hyperthyroid-associated osteoporosis. First, we observed that TSHR was downregulated in bone marrow mesenchymal stem cells (BMSCs) isolated from rats after culture in osteogenic medium for 7 days. Functionally, overexpression of TSHR accelerates BMSC osteogenic differentiation. Mechanistically, we predicted four potential miRNAs for TSHR. MiR-577 was validated to bind with TSHR. Rescue assays showed that miR-577 overexpression inhibited BMSC osteogenic differentiation via targeting TSHR. In vivo experiments showed that miR-577 aggravated bone loss and bone remodeling and our data showed that it is achieved by targeting TSHR in hyperthyroid-associated osteoporosis. This finding may deep our understanding of the pathogenesis of hyperthyroid-associated osteoporosis.

Long non-coding RNA NORAD aggravates acute myocardial infarction by promoting fibrosis and apoptosis via miR-577/COBLL1 axis.

Acute myocardial infarction (AMI) is one of the most common and serious cardiovascular diseases. With high morbidity and mortality, AMI has attracted the most attention. Emerging studies indicated that long noncoding RNAs (lncRNAs) play an important role in the progression of AMI. However, the role of NORAD in AMI remained unclear. The current study aimed to investigate the function and mechanism of NORAD in AMI. Bioinformatics tools and a wide range of assays including RT-qPCR, flow cytometry, TTC staining, western blot, luciferase reporter and caspase-3 activity assays were conducted to investigate the function and mechanism of NORAD in AMI. We found out that NORAD was significantly upregulated in AMI rats. Knockdown of NORAD alleviated H9c2 cell injury by reducing apoptosis and decreasing expression levels of fibrogenic factors. In addition, NORAD inhibition ameliorated AMI in a rat model by decreasing infarct size and fibrosis. We confirmed that NORAD bound to miR-577, which was downregulated in ischemia-reperfusion (I/R) rats and hypoxia-exposed H9c2 cells. Additionally, miR-577 combined with the 3'UTR of COBLL1, which was upregulated in I/R rats and hypoxia-exposed H9c2 cells. At last, rescue assay validated that the suppressive effects of NORAD knockdown on apoptosis and expression levels of fibrogenic factors were counteracted by COBLL1 overexpression. Overall, NORAD aggravates acute myocardial infarction by promoting fibrosis and apoptosis via the miR-577/COBLL1 axis. This novel discovery suggested that NORAD may serve as a potential therapeutic target for AMI patients.

LINC01094 triggers radio-resistance in clear cell renal cell carcinoma via miR-577/CHEK2/FOXM1 axis.

BACKGROUND: Radioresistance is an obstacle to limit efficacy of radiotherapy. Meanwhile, long non-coding RNAs (lncRNAs) have been reported to affect radioresistance. Here, we aimed to investigate lncRNAs involving radioresistance development of clear cell renal cell carcinoma (ccRCC), the most frequent type of renal cell carcinoma (RCC). METHODS: The mRNA and protein expressions of genes were measured via qRT-PCR and western blot. The relationships among genes were verified by RIP and luciferase reporter assay. The radioresistance of ccRCC cells was evaluated through clonogenic survival assay, MTT assay and TUNEL assay. RESULTS: LINC01094 was over-expressed in ccRCC cell lines. LINC01094 expression was increased along with the radiation exposure time and the final stable level was 8 times of the initial level. Knockdown of LINC01094 resulted in enhanced radiosensitivity of ccRCC cells. Mechanically, LINC01094 was a ceRNA of CHEK2 by sponging miR-577. Also, the enhancement of LINC01094 on ccRCC radioresistance was mediated by CHEK2-stabilized FOXM1 protein. CONCLUSION: LINC01094 facilitates ccRCC radioresistance by targeting miR-577/CHEK2/FOXM1 axis, blazing a new trail for overcoming radioresistance in ccRCC.

Long noncoding RNA MIR99AHG promotes gastric cancer progression by inducing EMT and inhibiting apoptosis via miR577/FOXP1 axis.

BACKGROUND: Long non-coding RNAs (lncRNAs) play a vital role in the genesis and development of human cancer. LncRNA MIR99AHG has been reported to be upregulated in acute myeloid leukemia (AML); however, its function in gastric cancer (GC) is still not clear. Here we were aiming to screen the prognostic lncRNA candidates and to explore the function of MIR99AHG in GC. METHODS: We have preliminarily screened some candidate lncRNA biomarkers in GC tissues through analyzing microarray datasets. The expression level of MIR99AHG in GC cell lines and tissues was monitored via qPCR. Survival analysis was performed with the patients of our hospital and TCGA database cases. CCK-8 assay, trans-well assay and flow cytometry were performed to determine cell proliferation, invasion, migration and apoptosis. Meanwhile, a target of MIR99AHG was predicted and identified by luciferase reporter gene detection experiments. RESULTS: MIR99AHG was strongly up-regulated in human GC and contributed to cancer progression. Kaplan-Meier analysis revealed that up-regulating MIR99AHG expression was positively correlated with unfavorable overall survival (P < 0.01) of patients from our hospital and TCGA database. Knockdown of MIR99AHG expression inhibited cell proliferation, invasion, migration and promoted cell apoptosis. Moreover, MIR99AHG worked as an oncogenic gene though competing for endogenous RNA (ceRNA) of miR-577. CONCLUSIONS: Our findings suggested that MIR99AHG contributes to malignant phenotypes of GC and may become a promising therapeutic target.

Circular RNA circ-CSPP1 regulates CCNE2 to facilitate hepatocellular carcinoma cell growth via sponging miR-577.

OBJECTIVE: Circ-centro-some/spindle pole-associated protein (CSPP1) has been confirmed to be characterized in diverse human malignancies and its ectopic expression may regulate tumor progression and development. However, in hepatocellular carcinoma (HCC), its biological role, clinical significance and molecular mechanism are still unclear. METHODS: Circ-CSPP1 expression and its prognostic values in HCC tissues were detected by qRT-PCR or in situ hybridization (ISH), and enriched by using Rnase R. The functional experiments (Circ-CSPP1 was overexpressed or knocked down) were performed in HCC cells. The HCC cell growth was analyzed by CCK-8 assay, transwell, wound healing and colony formation assays. The interation between circ-CSPP1 and miR-577/miR-577 and cyclin E2 (CCNE2) were determined by dual luciferase assay or RNA binding protein immunoprecipitation (RIP) assay. The RNA fluorescence in situ hybridization (FISH) assay was used to detect the subcellular distribution. Finally, an in vivo nude mouse tumor model was constructed. RESULTS: In HCC patients and cells, circ-CSPP1 was aberrantly expressed, and its upregulation predicted poor prognosis, and closely correlated with tumor size and TNM stage. Circ-CSPP1 resisted RnaseR digestion, indicating it is a circular RNA structure. Moreover, overexpression of circ-CSPP1 promoted HCC cell viability, colony formation, migration, and invasion in vitro. Knockdown of circ-CSPP1 showed contrary results. Circ-CSPP1 acts as a miR-577 sponge and positively regulated the target of miR-577, CCNE2. Besides, miR-577 inhibitor rescued the suppressive effects of circ-CSPP1 knockdown on HCC cell growth, whereas was completely reversed by silencing of CCNE2. Finally, the in vivo experiments confirmed that circ-CSPP1 knockdown regulated xenograft tumor volume and downregulated CCNE2, p-Rb, E2F1 and c-myc expression. CONCLUSION: These findings revealed that circ-CSPP1 contributed to HCC progression by positively regulating CCNE2 via miR-577, thus established its potential as new a prognostic and therapeutic marker for HCC patients.

miR-577 Regulates TGF-ß Induced Cancer Progression through a SDPR-Modulated Positive-Feedback Loop with ERK-NF-κB in Gastric Cancer.

Transforming growth factor ß (TGF-ß) drives epithelial-mesenchymal transition (EMT), playing vital roles in cancer metastasis. The crosstalk between microRNAs (miRNAs) and TGF-ß are frequently observed and involved in TGF-ß-induced EMT. Here, we determine that miR-577 is significantly upregulated in gastric cancer (GC). miR-577 expression is positively correlated with GC metastasis status and poor patient prognosis. Functional assays demonstrate that miR-577 promotes metastasis and chemoresistance by inducing EMT and stemness-like properties. Moreover, TGF-ß promotes the expression of miR-577, and miR-577 participates TGF-ß-mediated cancer metastasis. Mechanistically, TGF-ß activates miR-577 via NF-κB-mediated transcription, and miR-577 enhances TGF-ß signaling by targeting the serum deprivation protein response (SDPR), which directly interacts with ERK to inactivate the ERK-NF-κB pathway, hence forming a feedback loop to drive tumor metastasis. A plausible mechanism of EMT induction by the TGF-ß network is elucidated. Our findings suggest that the TGF-ß-miR-577-SDPR axis may be a potential prognostic marker and therapeutic target against cancer metastasis in GC.

TMPO-AS1 promotes cervical cancer progression by upregulating RAB14 via sponging miR-577.

BACKGROUND: Accumulating evidence has shown that long non-coding RNAs play a key role in cancer initiation and development. However, the effect of TMPO antisense RNA 1 (TMPO-AS1) on the progression of cervical cancer (CC) remains to be determined. METHODS: The mRNA expression of TMPO-AS1, miR-577 and RAB14 was measured by a quantitative reverse transcriptase-polymerase chain reaction. The protein level of RAB14 was detected by western blotting. The function of TMPO-AS1 in CC was measured via Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine and transwell assays, as well as by flow cytometry analysis. Nuclear-cytoplasmic fractionation and RNA-fluorescence in situ hybridization validated the subcellular position of TMPO-AS1. An interaction between miR-577 and TMPO-AS1 or RAB14 was confirmed by luciferase reporter, RNA pull-down and RNA immunoprecipitation assays. RESULTS: TMPO-AS1 was highly expressed in CC. In addition, TMPO-AS1 knockdown inhibited proliferation and migration, and also induced apoptosis. TMPO-AS1 located in the cytoplasm and promoted RAB14 expression by absorbing miR-577. RAB14 overexpression or miR-577 knockdown restored the suppressing effect of TMPO-AS1 knockdown on the biological behavior of CC cells. CONCLUSIONS: The present study has revealed a novel TMPO-AS1/miR-577/RAB14 regulatory axis in the pathogenesis of CC, highlighting TMPO-AS1 as a promising therapeutic target for CC patients.

Circular RNA circ_0008450 upregulates CXCL9 expression by targeting miR-577 to regulate cell proliferation and invasion in nasopharyngeal carcinoma.

As a kind of malignant tumor, nasopharyngeal carcinoma (NPC) has attracted increasing attention from researchers. As a member of the circular RNA (circRNA) family, circ_0008450 has been investigated in hepatocellular carcinoma but not in NPC. This study aims to reveal the special biologic role and mechanism of circ_0008450 in NPC. qRT-PCR analysis was conducted to test the level of circ_0008450 in different tissues and cells. Loss/Gain of function assay was utilized to detect the influence of silenced/overexpressed circ_0008450 on the proliferation, apoptosis, migration, and invasion of NPC cells. The mechanism of circ_0008450 was assessed by performing qRT-PCR and luciferase reporter experiments. The results showed that circ_0008450 was elevated in NPC tissues and cells. Silenced circ_0008450 could inhibit cell proliferation, and metastatic properties and increased the number of apoptotic cells. Ectopically expressed circ_0008450 strengthened the abovementioned malignant biological behaviors. Mechanistically, circ_0008450 reduced miR-577-mediated repression of CXCL9, resulting in facilitating the oncogenic functions of NPC. In conclusion, circ_0008450 acts as an oncogene in NPC cells through regulating miR-577/CXCL9 signaling. Our findings might provide a new therapeutic target for treating NPC.

Long non-protein coding RNA DANCR functions as a competing endogenous RNA to regulate osteoarthritis progression via miR-577/SphK2 axis.

Long noncoding RNAs (lncRNAs) have been known to be involved in multiple diverse diseases, including osteoarthritis (OA). This study aimed to explore the role of differentiation antagonizing non-protein coding RNA (DANCR) in OA and identify the potential molecular mechanisms. The expression of DANCR in cartilage samples from patients with OA was detected using quantitative reverse transcription-polymerase chain reaction. The effects of DANCR on the viability of OA chondrocytes and apoptosis were explored using cell counting kit 8 assay and flow cytometry assay, respectively. Additionally, the interaction among DANCR, miR-577, and SphK2 was explored using dual-luciferase reporter and RIP assays. The present study found that DANCR was significantly upregulated in patients with OA. Functional assays demonstrated that DANCR inhibition suppressed the proliferation of OA chondrocytes and induced cell apoptosis. The study also showed that DANCR acted as a competitive endogenous RNA to sponge miR-577, which targeted the mRNA of SphK2 to regulate the survival of OA chondrocytes. In conclusion, the study revealed that lncRNA DANCR might promote the proliferation of OA chondrocytes and reduce apoptosis through the miR-577/SphK2 axis. Thus, lncRNA DANCR might be considered as a potential therapeutic target for OA treatment.

Up-regulated lnc-SNHG1 contributes to osteosarcoma progression through sequestration of miR-577 and activation of WNT2B/Wnt/ß-catenin pathway.

Long noncoding RNA small nucleolar RNA host gene 1 (lnc-SNHG1) was reported to play an oncogenic role in the progression of cancers. However, the roles of SNHG1 and its molecular mechanism in osteosarcoma (OS) cells are largely unknown. In present study, we found that the expression of SNHG1 was up-regulated in OS tissues and cell lines. OS patients with the high SNHG1 expression were positively correlated with tumor size, TNM stage and lymph node metastasis. In addition, SNHG1 overexpression promoted cell proliferation, cell migration and EMT process in U2OS and MG63 cells and tumor growth in vivo. Furthermore, we also found that miR-577 could act as a ceRNAof SNHG1 in OS cells and the promotion of OS progression induced by lnc-SNHG1 overexpression required the inactivity of miR-577. Besides, we identified that WNT2B acted as a target of miR-577, and WNT2B played the oncogenic role in OS cells by activating Wnt/ß-catenin pathway. In short, our study suggested that lnc-SNHG1 could promote OS progression via miR-577 and WNT2B. The lnc-SNHG1/miR-577/WNT2B/Wnt/ß-catenin axis regulatory network might provide a potential new therapeutic strategy for OS treatment.

microRNA-577 suppresses tumor growth and enhances chemosensitivity in colorectal cancer.

In this work, we aimed to determine the expression and biological functions of microRNA (miR)-577 in colorectal cancer (CRC). The results showed that miR-577 was downregulated in CRC specimens and cell lines. Restoration of miR-577 significantly suppressed the proliferation and colony formation and induced a G0/G1 cell cycle arrest in CRC cells. 5-Fluorouracil (5-FU)-resistant SW480 cells (SW480/5-FU) were found to have elevated levels of miR-577. Ectopic expression of miR-577 enhanced 5-FU sensitivity in SW480/5-FU cells. Heat shock protein 27 (HSP27) was identified as a target gene of miR-577. Enforced expression of HSP27 reversed the effects of miR-577 on CRC cell growth and 5-FU sensitivity. Xenograft tumors derived from miR-577-overexpressing SW480 cells exhibited significantly slower growth than control tumors. In conclusion, our results support that miR-577 acts as a tumor suppressor in CRC likely through targeting HSP27. Therefore, miR-577 may have therapeutic potential in the treatment of CRC.

NS5ATP6 modulates intracellular triglyceride content through FGF21 and independently of SIRT1 and SREBP1.

The prevalence of nonalcoholic fatty liver disease (NAFLD) is rising strikingly in Western countries and China. The molecular biological mechanism of NAFLD remains unclear, with no effective therapies developed so far. Fibroblast growth factor 21 (FGF21) is a recently discovered hormone, with safe lipid lowering effects. FGF21 analogs are being developed for clinical application. Here we demonstrated that a novel gene, NS5ATP6, modulated intracellular triglyceride (TG) content independently of sirtuin1 (SIRT1) and sterol regulatory element binding protein 1 (SREBP1) in HepG2 cells. Interestingly, NS5ATP6 regulated FGF21 expression both at the mRNA and protein levels. The modulatory effects of NS5ATP6 on intracellular TG content depended upon FGF21. Further studies revealed that NS5ATP6 decreased the promoter activity of FGF21. In addition, NS5ATP6 regulated the expression of miR-577, which directly targeted and regulated FGF21. Therefore, miR-577 might be involved in NS5ATP6 regulation of FGF21 at the post-transcriptional level. In conclusion, NS5ATP6 regulates the intracellular TG level via FGF21, and independently of SIRT1 and SREBP1.

miR-577 inhibits glioblastoma tumor growth via the Wnt signaling pathway.

microRNAs (miRNAs) are commonly altered in glioblastoma. Publicly available algorithms suggest the Wnt pathway is a potential target of miR-577 and the Wnt pathway is commonly altered in glioblastoma. Glioblastoma has not been previously evaluated for miR-577 expression. Glioblastoma tumors and cell lines were evaluated for their expression of miR-577. Cell lines were transfected with miR-577, miR-577-mutant, or control mimics to evaluate the effect of miR-577 expression on cell proliferation in vitro and in an animal model. Wnt pathway markers were also evaluated for their association with miR-577 expression. miR-577 expression was decreased in 33 of 40 (82.5%) glioblastoma tumors and 5 of 6 glioblastoma cell lines. miR-577 expression correlated negatively with cell growth and cell viability. miR-577 down-regulation was associated with increased expression of the Wnt signaling pathway genes lipoprotein receptor-related protein (LRP) 6 (LRP6) and ß-catenin. Western blot analysis confirmed decreased expression of the Wnt signaling pathway genes Axin2, c-myc, and cyclin D1 in miR-577 transfected cells. miR-577 expression is down-regulated in glioblastoma. miR-577 directly targets Wnt signaling pathway components LRP6 and ß-catenin. miR-577 suppresses glioblastoma multiforme (GBM) growth by regulating the Wnt signaling pathway.

[The Targeted Regulating Role of Has-miR-577 and Has-miR-583 on Gene FGF-21 Detected by the Dual Luciferase Reporter System.]

OBJECTIVES: To determine the targeted regulating role of has-miR-577 and has-miR-583 on the expression of fibroblast growth factor 21 (FGF-21) based on a constructed luciferase reporter FGF-21 gene vector. METHODS: The site of has-miR-577 and has-miR-583 target genes FGF-21 were predicted by the bioinformatics analyzing tools online.FGF-21 gene fragments,combined with has-miR-577 or has-miR-583 sequences and mutant sequences,were designed and synthesized.The wild type (psiCHECK2-FGF-21) and mutant (psiCHECK2-FGF-21-mut) luciferase reporter gene carriers were constructed.The relevant plasmids [hsa-miR-577mimics,hsa-miR-583 mimics or miR negative control (miR-NC)] and luciferase reporter gene carrier (wild type or mutant ) were co-transfected into 293T cells.The luciferase reporter system was used to detect the luciferase activity.The effects of has-miR-577 and has-miR-583 on the expression of FGF-21 were observed. RESULTS: The double enzyme electrophoresis and sequencing results showed that the gene fragment size and sequences of the wild type (psiCHECK2-FGF-21) and mutant (psiCHECK2-FGF-21-mut) carriers met expectations of the experiment.The luciferase assays revealed that has-miR-577 and has-miR-583 significantly diminished luciferase activity from the reporter vector containing 3'UTR of FGF-21 (P<0.05),whereas no suppression of luciferase activity was found in the mutant (psiCHECK2-FGF-21-mut). CONCLUSIONS: FGF-21 gene can be targeted by has-miR-577 and has-miR-583.

Circ_0000376 regulates miR-577/HK2/LDHA signaling pathway to promote the growth, invasion and glycolysis of osteosarcoma.

BACKGROUND: Many studies have confirmed that circular RNAs (circRNAs) mediate the malignant progression of various tumors including osteosarcoma (OS). Our study is to uncover novel molecular mechanisms by which circ_0000376 regulates OS progression. METHODS: The expression of circ_0000376, microRNA (miR)-577, hexokinase 2 (HK2) and lactate dehydrogenase-A (LDHA) was determined by quantitative real-time PCR. OS cell proliferation, apoptosis and invasion were measured using cell counting kit 8 assay, colony formation assay, EdU assay, flow cytometry and transwell assay. Besides, cell glycolysis was assessed by testing glucose consumption, lactate production, and ATP/ADP ratios. Protein expression was examined by western blot analysis. The interaction between miR-577 and circ_0000376 or HK2/LADA was verified by dual-luciferase reporter assay. The role of circ_0000376 on OS tumor growth was explored by constructing mice xenograft models. RESULTS: Circ_0000376 had been found to be upregulated in OS tissues and cells. Functional experiments revealed that circ_0000376 interference hindered OS cell growth, invasion and glycolysis. Circ_0000376 sponged miR-577 to reduce its expression. In rescue experiments, miR-577 inhibitor abolished the regulation of circ_0000376 knockdown on OS cell functions. MiR-577 could target HK2 and LDHA in OS cells. MiR-577 suppressed OS cell growth, invasion and glycolysis, and these effects were reversed by HK2 and LDHA overexpression. Also, HK2 and LDHA expression could be regulated by circ_0000376. In vivo experiments showed that circ_0000376 knockdown inhibited OS tumorigenesis. CONCLUSION: Circ_0000376 contributed to OS growth, invasion and glycolysis depending on the regulation of miR-577/HK2/LDHA axis, providing a potential target for OS treatment.

Hsa_circRNA_0084043 promoting tumorigenesis in glioma through miR-577 sponging.

Circular RNAs (circRNAs) are important non-coding RNAs (ncRNAs) involved in the development of multiple human diseases, especially cancers. circRNA_0084043 is significantly involved in the progression of melanoma. However, whether circRNA_0084043 is associated with glioma remains unknown. In this study, the upregulation of circRNA_0084043 in glioma and the association between circRNA_0084043 and glioma grade were identified. Our results showed that circRNA_0084043 is significantly involved in the proliferative, migratory, and invasive capacities of glioma cells. The results obtained from starBase, luciferase reporter assays, RNA immunoprecipitation assays, and RNA pull-down assays demonstrated that circRNA_0084043 acts as a direct sponge for miR-577. TargetScan algorithm was used to identify potential miR-577 targets, it was found that sorting nexin 5 (SNX5) is a candidate bound to miR-577. Finally, cell experiments testified that circRNA_0084043 enhanced growth, migration and invasion of glioma through the regulation of miR-577-mediated SNX5. Taken together, we concluded that circRNA_0084043 in the miR-577/SNX5 axis can be used as a candidate target for glioma therapy.

LncRNA NORAD facilitates oral squamous cell carcinoma progression by sponging miR-577 to enhance TPM4.

BACKGROUND: Long non-coding RNAs (lncRNAs) have been reported to be vital factors to affect the expression of genes and proteins. Also, it has been proved that the abnormal expression or mutation of lncRNAs stands as a signal of metastasis and proliferation of cancer. Nevertheless, the majority of lncRNAs still need to be explored in abundant cancers especially in oral squamous cell carcinoma (OSCC). METHODS: RT-qPCR assays were applied to test the expression of RNAs. Mechanism assays were performed to verify the combination among NORAD, TPM4 and miR-577. Also, functional assays were conducted to verify the function of RNAs on OSCC cells. RESULTS: LncRNA NORAD was highly expressed in OSCC tissues and cells. NORAD silencing repressed the biological behaviors of OSCC cells. MiR-577 was found in OSCC with low expression, and RIP assays illustrated that NORAD, miR-577 and TPM4 coexisted in RNA-induced silencing complexes. Rescue assays proved that the overexpression of TPM4 could recover the effect of NORAD silencing on OSCC progression. CONCLUSIONS: It was revealed that NORAD functioned as a tumor promoter to sponge miR-577 thus elevating TPM4 in OSCC, which indicated that NORAD was worthy to be studied as a target for the treatment of OSCC.