scholarly journals CircVAPA promotes proliferation and metastasis of retinoblastoma by modulating miR-615-3p and SMARCE1

2020 ◽  
Author(s):  
Qibin Xu

Abstract Background Growing evidence reveals that circular RNAs (circRNAs) play roles in cancer development. However, the effects and possible mechanisms of circRNAs in retinoblastoma (RB) are far from clear. Methods circVAPA expression pattern was identified by RT-qPCR. CircVAPA induced effects on RB cells were tested by CCK-8, clone forming, flow cytometry and transwell assays. Bioinformatics assay, rescue experiments and dual luciferase tests were applied for mechanism exploration. Additionally, mouse models were established for in vivo assays. Results circVAPA was expressed at high levels in human RB specimen and RB cell lines, and was correlated with poor outcomes of Rb patients. Knockdown of circVAPA could suppress the malignant phenotype of RB. Mechanistic experiments demonstrated that miR-615-3p could reverse the circVAPA induced effects on RB cells, and the downstream oncogene SMARCE1 was positively regulated by circVAPA via miR-615-3p. Further, in vivo analysis confirmed the findings. Conclusions In summary, circVAPA promoted RB proliferation and metastasis by sponging miR-615-3p, thereby upregulating SMARCE1. CircVAPA is a potential biomarker of Rb therapy.

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Junjie Cen ◽  
Yanping Liang ◽  
Yong Huang ◽  
Yihui Pan ◽  
Guannan Shu ◽  
...  

Abstract Background There is increasing evidence that circular RNAs (circRNAs) have significant regulatory roles in cancer development and progression; however, the expression patterns and biological functions of circRNAs in renal cell carcinoma (RCC) remain largely elusive. Method Bioinformatics methods were applied to screen for circRNAs differentially expressed in RCC. Analysis of online circRNAs microarray datasets and our own patient cohort indicated that circSDHC (hsa_circ_0015004) had a potential oncogenic role in RCC. Subsequently, circSDHC expression was measured in RCC tissues and cell lines by qPCR assay, and the prognostic value of circSDHC evaluated. Further, a series of functional in vitro and in vivo experiments were conducted to assess the effects of circSDHC on RCC proliferation and metastasis. RNA pull-down assay, luciferase reporter and fluorescent in situ hybridization assays were used to confirm the interactions between circSDHC, miR-127-3p and its target genes. Results Clinically, high circSDHC expression was correlated with advanced TNM stage and poor survival in patients with RCC. Further, circSDHC promoted tumor cell proliferation and invasion, both in vivo and in vitro. Analysis of the mechanism underlying the effects of circSDHC in RCC demonstrated that it binds competitively to miR-127-3p and prevents its suppression of a downstream gene, CDKN3, and the E2F1 pathway, thereby leading to RCC malignant progression. Furthermore, knockdown of circSDHC caused decreased CDKN3 expression and E2F1 pathway inhibition, which could be rescued by treatment with an miR-127-3p inhibitor. Conclusion Our data indicates, for the first time, an essential role for the circSDHC/miR-127-3p/CDKN3/E2F1 axis in RCC progression. Thus, circSDHC has potential to be a new therapeutic target in patients with RCC.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Zuojun Zhang ◽  
Ming Zhao ◽  
Guojie Wang

Abstract Background Osteosarcoma is a most common bone malignant tumor which threatens children and adolescents. Circular RNAs (circRNAs) fundamentally play essential roles in the progress and development of human cancers by sponging with microRNAs (miRNAs). However, the role of circRNAs in osteosarcoma is not clear. The aim of the study was to investigate the roles and molecular mechanism of circRNAs in osteosarcoma. Results The data from qRT-PCR showed that circ_0051079 expression was higher in osteosarcoma cells and tissues compared to their normal controls. Meanwhile, bioinformatic analysis indicated that circ_0051079 was a sponge of miR-26a-5p, which was verified by luciferase activity assay. Subsequently, TGF-β1 was verified as a putative target mRNA of miR-26a-5p by luciferase assay. Cellular function assays were conducted and the findings revealed that circ_0051079/miR-26a-5p/TGF-β1 regulated osteosarcoma proliferation and metastasis. Conclusion The study demonstrated that circ_0051079 could act as an oncogene via regulating miR-26a-5p/TGF-β1 and a potential biomarker for osteosarcoma diagnose.


2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Sen Wang ◽  
Dong Tang ◽  
Wei Wang ◽  
Yining Yang ◽  
Xiaoqing Wu ◽  
...  

Abstract Background As a novel class of non-coding RNAs, circular RNAs (circRNAs) are key regulators of the development and progression of different cancers. However, little is known about the function and biological mechanism of circLMTK2, also named hsa_circ_0001725, in gastric cancer (GC) tumourigenesis. Methods circLMTK2 was identified in ten paired cancer specimens and adjacent normal tissues by RNA sequencing and genome-wide bioinformatic analysis and verified by quantitative real-time PCR (qRT-PCR). Knockdown or exogenous expression of circLMTK2 combined with in vitro and in vivo assays were performed to prove the functional significance of circLMTK2. The molecular mechanism of circLMTK2 was demonstrated by searching the CircNet database and confirmed by RNA in vivo precipitation assays, western blotting, luciferase assays and rescue experiments. Results circLMTK2 was frequently upregulated in GC tissues, and high circLMTK2 expression was associated with poor prognosis, lymph node metastasis and poor TNM stage in GC patients. Functionally, circLMTK2 overexpression promoted GC cell proliferation and tumourigenicity in vitro and in vivo. Furthermore, ectopic circLMTK2 expression enhanced GC cell migration and invasion in vitro and tumour metastasis in vivo. In addition, we demonstrated that circLMTK2 could sponge miR-150-5p, thus indirectly regulating the c-Myc expression and contributing to GC tumourigenesis. Conclusion Our findings demonstrate that circLMTK2 functions as a tumour promoter in GC through the miR-150-5p/c-Myc axis and could thus be a prognostic predictor and therapeutic target for GC.


2020 ◽  
Vol 29 ◽  
pp. 096368972092614
Author(s):  
Ji-Hai Wang ◽  
Xue-Jian Wu ◽  
Yong-Zhuang Duan ◽  
Feng Li

Circular RNAs (circRNAs) act crucial roles in the progression of multiple malignancies including osteosarcoma (OS). But, the underlying mechanisms by which hsa_circ_0017311 (circCNST) contributes to the tumorigenesis of OS remain poorly understood. Our present study aimed to explore the role and mechanisms of circCNST in OS tumorigenesis. The differentially expressed circRNAs were identified by the Gene Expression Omnibus database. The association of circCNST with clinicopathological features and prognosis in patients with OS was analyzed by RNA fluorescence in situ hybridization (FISH) and quantitative real-time polymerase chain reaction (PCR) analysis. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), colony formation assays, and a xenograft tumor model were conducted to assess the role of circCNST in OS cells in vitro and in vivo. CircCNST-specific binding with miR-421 was confirmed by FISH, luciferase gene report, and RNA immunoprecipitation assays. As a result, we found that the expression levels of circCNST were dramatically increased in OS tissues and cell lines as compared with the adjacent normal tissues, and it was associated with tumor size and poor survival in OS patients. Knockdown of circCNST repressed cell viability, colony formation, and xenograft tumor growth, while restored expression of circCNST reversed these effects. Furthermore, circCNST was colocalized with miR-421 in the cytoplasm and acted as a sponge of miR-421, which attenuated circCNST-induced proliferation-promoting effects in OS cells by targeting SLC25A3. In conclusion, our findings demonstrate that circCNST promotes the tumorigenesis of OS cells by sponging miR-421, and provides a potential biomarker for patients with OS.


Epigenomics ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 935-953 ◽  
Author(s):  
Fengjiao Han ◽  
Chaoqin Zhong ◽  
Wei Li ◽  
Ruiqing Wang ◽  
Chen Zhang ◽  
...  

Aim: Accumulating evidence has indicated that circular RNAs (circRNAs) are involved in cancer biology. However, their roles in acute myeloid leukemia (AML) remain unclear. Therefore, we aimed to define novel circRNAs involved the development and progression of AML. Materials & methods: We used circRNAs microarray to determine the differential expression profile. Quantitative reverse transcription PCR analyzed the expression of hsa_circ_0001947. The siRNA assesses the function of hsa_circ_0001947 in vitro and in vivo. A dual-luciferase and mimics/inhibitor were to determine the target gene relationship. Results: hsa_circ_0001947 functions as a tumor inhibitor to suppress AML cell proliferation through hsa-miR-329-5p/ CREBRF axis. Conclusion: hsa_circ_0001947 may be as a novel potential biomarker for the treatment of AML.


2020 ◽  
Author(s):  
Zhonghui Chen ◽  
Weibing Zhang ◽  
Ming Deng ◽  
Yan Zhou ◽  
Yaming Li

AbstractBackgroundIntervertebral disc degeneration (IDD) can induce profound global socioeconomic burdens. Recent studies have suggested that circular RNAs might have crucial functions in the progression of IDD. The purpose of this study was to identify a specific circular RNA and to investigate its regulatory mechanism in IDD.MethodsCircGLCE was selected after microarray analyses and was further analysed by RT-qPCR and FISH. After silencing CircGLCE, its function was assessed with RT-qPCR, immunofluorescence analysis and flow cytometry. Based on Sanger sequencing, miR-587 was identified as a direct target of CircGLCE, and it was further examined with RNA pulldown assays, RT-qPCR, dual luciferase assays and FISH. After silencing CircGLCE or miR-587, western blotting, immunofluorescence analysis, and flow cytometry were conducted. STAP1 was assessed by RT-qPCR and luciferase assay, and experiments with silenced and overexpressed miR-587 were performed. A rescue experiment was also included. In an IDD rat model, the in vivo effects of overexpressing CircGLCE on IDD were analysed with imaging techniques, TUNEL staining, FISH, western blotting, H&E staining and immunohistochemistry.ResultsCircGLCE was found to stably exist in the cytoplasm of nucleus pulposus (NP) cells. It was downregulated in IDD. Knockdown of CircGLCE promoted apoptosis and induced the expression of matrix-degrading enzymes in NP cells. CircGLCE served as a miR-587 sponge in NP cells. Inhibiting miR-587 counteracted the IDD-enhancing effect caused by silencing CircGLCE. STAP1 served as the miRNA target that mediated the functions of miR-587. Overexpressing CircGLCE alleviated IDD in vivo.ConclusionsCircGLCE attenuates IDD by regulating the apoptosis of NP cells and by regulating ECM degradation through the targeting of miR-587/STAP1. CircGLCE may be a potential therapeutic target for IDD treatments.


2021 ◽  
Vol 12 (12) ◽  
Author(s):  
Ping Liu ◽  
Ruiting Fu ◽  
Kai Chen ◽  
Lu Zhang ◽  
Shasha Wang ◽  
...  

AbstractHigh-grade serous ovarian cancer (HGSOC) is a common and lethal cancer of the female reproductive system. Long non-coding RNAs (lncRNAs) are aberrantly expressed in various cancers and play crucial roles in tumour progression. However, their function and molecular mechanism in HGSOC remain largely unknown. Based on public databases and bioinformatics analyses, the overexpression of lncRNA CTBP1-DT in HGSOC tissues was detected and validated in a cohort of HGSOC tissues. High expression of lncRNA CTBP1-DT was associated with poor prognosis and was an independent risk factor for survival. Overexpression of lncRNA CTBP1-DT promoted malignant biological behaviour of HGSOC cells, whereas its depletion induced growth arrest of HGSOC cells by vitro and in vivo assays. Mechanistically, lncRNA CTBP1-DT could competitively bind to miR-188-5p to protect MAP3K3 from degradation. Moreover, our results revealed that ETV5 could specifically interact with the promoter of lncRNA CTBP1-DT and activate its transcription. Collectively, these results reveal a novel ETV5/lncRNA CTBP1-DT/miR-188-5p/MAP3K3 pathway for HGSOC progression and suggest that lncRNA CTBP1-DT might be a potential biomarker and therapeutic target for HGSOC.


2020 ◽  
Vol 10 (4) ◽  
pp. 372-383
Author(s):  
Rajani Kurup ◽  
Ajikumaran Nair Sadasivan ◽  
Uthayakumari Kalavathy ◽  
Sabulal Baby

Background: Polyscias guilfoylei, commonly called ‘geranium aralia’, is an erect shrub with dark green leaves. P. guilfoylei has been introduced to tropical countries and is generally cultivated in gardens for ornamental purposes. There are no previous studies on the essential oil of P. guilfoylei and its biological activities. Objective: In this study, we report the chemical profile of P. guilfoylei leaf essential oil and its anticancer activity tested by various in vitro and in vivo assays. Methods: The chemical profile of P. guilfoylei leaf oil was elucidated by Gas Chromatographic analyses (GC-FID, GC-MS). Anticancer activity of P. guilfoylei leaf oil was tested by MTT, morphological observations, DNA ladder, comet, caspase, flow cytometry and in vivo assays. Results: Gas chromatographic profiling of P. guilfoylei leaf oil identified 50 constituents (β-selinene 49.59%, α-selinene 21.68%, (Z)-falcarinol 11.65%). In MTT assay, P. guilfoylei leaf oil at 50, 25, 10, 5 and 1 μg/ml showed 98.6 ± 1.2, 95.3 ± 0.78, 76.8 ± 1.59, 43.6 ± 0.99 and 39.8 ± 1.17% DLA cell death, respectively (CD50 5.96 μg/ml). In flow cytometry, the majority of P. guilfoylei leaf oil (25 μg/ml) treated DLA cells showed an accumulation/cell arrest in G2M phase (61.7 ± 2.6%). In P. guilfoylei leaf oil treated mice (40 days), 5 animals (83.3%, each) were protected in 25, 50 mg/kg groups. Conclusion: P. guilfoylei leaf oil, with minimal toxicity to normal cells, exhibited significant anticancer activity against lymphoma cells enhancing its potential as an anticancer agent.


2020 ◽  
Vol 15 (1) ◽  
pp. 476-487
Author(s):  
Bin Xiao ◽  
Xusheng Zhang ◽  
Xiaojuan Li ◽  
Zhipeng Zhao

AbstractOsteosarcoma (OS) is a common malignant tumor in the world. Circular RNAs are endogenous non-coding RNAs that have been linked to the development of cancer. However, the role of circ_001569 in OS progression is still unclear. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of circ_001569, microRNA-185-5p (miR-185-5p) and flotillin-2 (FLOT2). The abilities of cell proliferation, migration and invasion were evaluated by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and Transwell assays, respectively. Also, western blot analysis was performed to assess the levels of epithelial–mesenchymal transition (EMT)-related proteins and FLOT2 protein. Besides, the dual-luciferase reporter assay was used to verify the interactions among circ_001569, miR-185-5p and FLOT2. Circ_001569 expression was increased in OS tissues and cells, and its knockdown reduced the proliferation, migration, invasion and EMT of OS cells. MiR-185-5p could interact with circ_001569. Inhibition of miR-185-5p could recover the suppression effects of silenced-circ_001569 on the proliferation and metastasis of OS cells. Furthermore, FLOT2 was a target of miR-185-5p. Overexpressed FLOT2 could restore the inhibition effects of miR-185-5p mimic on the proliferation and metastasis of OS cells. Also, FLOT2 expression was regulated by circ_001569 and miR-185-5p. In addition, circ_001569 knockdown also reduced the OS tumor growth in vivo. Circ_001569 might act as an oncogene in OS progression by regulating the miR-185-5p/FLOT2 axis, which provided a reliable new approach for the treatment of OS patients.


2020 ◽  
Author(s):  
Xinglong Dai ◽  
Jianjun Liu ◽  
Xiong Guo ◽  
Anqi Cheng ◽  
Xiaoya Deng ◽  
...  

Background: Mounting evidence has displayed critical roles of circular RNAs (circRNAs) in multiple cancers. The underlying mechanisms by which circFGD4 contributed to gastric cancer (GC) are still unclear. Methods: The levels and clinical values of circFGD4 in GC patients were detected and analysed by quantitative real-time PCR. The biological roles of circFGD4 in GC were assessed in vitro and in vivo experiments. Dual-luciferase reporter, fluorescence in situ hybridization, RNA immunoprecipitation, biotin-coupled RNA pull-down, and TOP/Flash and FOP/Flash reporter gene assays were employed to evaluate the effects of circFGD4 on miR-532-3p-mediated adenomatous polyposis coli (APC)/β-catenin signalling in GC cells. Results: circFGD4 expression was down-regulated the most in human GC tissues and cell lines. Low expression of circFGD4 was correlated with poor tumour differentiation, lymphatic metastasis, and poor prognosis of GC patients. circFGD4 suppressed GC cell viability, colony formation, migration, induced epithelial-mesenchymal transition (EMT) and tumorigenesis and metastasis in vivo. Next, we validated that circFGD4 acted as a sponge of miR-532-3p to relieve the tumour-promoting effects of miR-532-3p on its target APC. The mechanistic analysis demonstrated that the circFGD4 suppressed GC cell viability, migration, and EMT by modulating the miR-532-3p/APC axis to inactivate the β-catenin signalling. Conclusion: circFGD4 suppressed GC progression through sponging miR-532-3p and enhancing APC expression to inactivate the β-catenin signalling. Thus circFGD4 provides a novel potential biomarker and valuable therapeutic strategy for GC.


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