Circular RNA SFMBT2 Inhibits the Proliferation and Metastasis of Glioma Cells Through Mir-182-5p/Mtss1 Pathway

Glioma is a common type of tumor in human central nervous system, and it is characterized with high mobility and mortality. The prognosis of patients with advanced glioma remains poor. Thus, it is necessary to develop novel therapeutic approaches for the treatment of this disease. Circular RNAs are a group of noncoding RNAs which have been detected in eukaryotic cells. They are tissue-specific and characterized with a more stable structure compared with linear RNAs. Recently, studies have revealed that certain circular RNAs are involved in biological processes such as gene regulation; however, the functions of most circular RNAs remain unknown and require further investigation. Furthermore, circular RNAs can act as “sponges” of its target microRNA, consequently suppressing their activity. Additionally, impaired expression of circular RNAs is reported in different diseases including cancer. In our study, low expression of circular RNA Scm like with 4 Mbt domains 2 was detected in glioma samples. Furthermore, reduced circRNA Scm like with 4 Mbt domains 2 expression was observed in human glioma cell lines compared to normal astrocyte cells. Additionally, overexpression of circRNA Scm like with 4 Mbt domains 2 suppressed the growth and metastasis of glioma cells in vitro. Moreover, microRNA-182-5p could be a downstream molecule of circRNA Scm like with 4 Mbt domains 2. The influenced of microRNA-182-5p-induced proliferation, migration, and invasion of glioma cells could be abrogated by overexpressed circRNA Scm like with 4 Mbt domains 2. In addition, metastasis suppressor 1 was predicted as a novel target of microRNA-182-5p, and its expression was restored by circRNA Scm like with 4 Mbt domains 2. In summary, our findings provided novel insight into the roles of circRNA Scm like with 4 Mbt domains 2 in glioma. More importantly, circRNA Scm like with 4 Mbt domains 2/microRNA-182-5p/metastasis suppressor 1 axis could be a putative therapeutic target for the treatment of patients with glioma.

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Silencing of hsa_circ_0000515 Inhibits Proliferation, Migration and Invasion of Gastric Cancer Cells by Sponging miR-615-5p In Vitro

Journal of Biomaterials and Tissue Engineering ◽

10.1166/jbt.2021.2733 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1466-1476

Author(s):

Xuli Wang ◽

Aiping Wang

Keyword(s):

Gastric Cancer ◽

Underlying Mechanism ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Pcr Analysis ◽

Circular Rnas ◽

Loss Of Function ◽

Gastric Cancer Cells ◽

Novel Target

Circular RNAs (circRNAs) have been reported to participate in the molecular mechanism of human cancers. This study investigates the role of circRNA hsa_circ_0000515 in gastric cancer (GC) cells and the underlying mechanism associated with microRNA-615-5p (miR-615-5p). qRT-PCR analysis showed the upregulation of hsa_circ_0000515 and downregulation of miR-615-5p in GC cell lines. Loss-of-function experiments indicated that suppression of hsa_circ_0000515 inhibited cell proliferation, migration, and invasion. Dual-luciferase reporter assay highlighted that hsa_circ_0000515 was able to act as a ceRNA of miR-615-5p. Furthermore, hsa_circ_0000515 could interact with splicing factors and bind miR-615-5p to regulate progression of GC cells. Deficiency of miR-615-5p reverses the inhibitory roles of si-hsa_circ_0000515 on the proliferation, migration, and invasion of GC cells. The findings highlighted the promising uses of hsa_circ_0000515 as a likely novel target for gastric cancer treatment.

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Circular RNA circFAT1(e2) Promotes Colorectal Cancer Tumorigenesis via the miR-30e-5p/ITGA6 Axis

Computational and Mathematical Methods in Medicine ◽

10.1155/2021/9980459 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Fei Pan ◽

Dongqing Zhang ◽

Na Li ◽

Mei Liu

Keyword(s):

Colorectal Cancer ◽

Circular Rna ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Circular Rnas ◽

Small Interfering Rnas ◽

Regulatory Relationship ◽

Downstream Target ◽

Normal Tissues

circRNAs (circular RNAs) are a family of noncoding RNAs and have diverse physiological and pathological functions. However, the functions and mechanisms of circRNAs in the development and progression of colorectal cancer (CRC) remain largely unknown. Here, we aimed to explore the functions and roles of circFAT1(e2) in CRC. qRT-PCR revealed that circFAT1(e2) in CRC tumor tissues was upregulated compared with that in adjacent normal tissues and was also upregulated in CRC cell lines. Small interfering RNAs (siRNAs) against circFAT1(e2) were used to decrease the expression of circFAT1(e2) in HCT116 and RKO cells in vitro. The roles of circFAT1(e2) in CRC cell metastasis and proliferation were then determined by transwell and CCK-8 assays. The results showed that circFAT1(e2) silencing markedly suppressed CRC growth. Moreover, we identified circFAT1(e2) as a promoter of CRC metastasis. Knockdown of circFAT1(e2) evidently reduced HCT116 and RKO cell migration and invasion. Furthermore, the regulatory relationship between circFAT1(e2) and its target miRNAs was verified by a luciferase reporter assay. We demonstrated that circFAT1(e2) could sponge miR-30e-5p, which regulated the expression level of integrin α6 (ITGA6), the downstream target gene of miR-30e-5p. Rescue assays demonstrated that knockdown of miR-30e-5p enhanced CRC proliferation and migration via ITGA6. Taken together, our results reveal the novel oncogenic roles of circFAT1(e2) in CRC through the miR-30e-5p/ITGA6 axis.

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circLMTK2 acts as a sponge of miR-150-5p and promotes proliferation and metastasis in gastric cancer

Molecular Cancer ◽

10.1186/s12943-019-1081-4 ◽

2019 ◽

Vol 18 (1) ◽

Cited By ~ 15

Author(s):

Sen Wang ◽

Dong Tang ◽

Wei Wang ◽

Yining Yang ◽

Xiaoqing Wu ◽

...

Keyword(s):

Gastric Cancer ◽

Bioinformatic Analysis ◽

Migration And Invasion ◽

Circular Rnas ◽

Normal Tissues ◽

Tumour Metastasis ◽

Genome Wide ◽

Proliferation And Metastasis

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.

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Circ-ZFR Promotes Progression of Bladder Cancer by Upregulating WNT5A Via Sponging miR-545 and miR-1270

Frontiers in Oncology ◽

10.3389/fonc.2020.596623 ◽

2021 ◽

Vol 10 ◽

Author(s):

Liping Luo ◽

Pingping Miao ◽

Yao Ming ◽

Jie Tao ◽

Hongchun Shen

Keyword(s):

Bladder Cancer ◽

Cell Lines ◽

Pearson Correlation ◽

Survival Rates ◽

Circular Rna ◽

Luciferase Assay ◽

Migration And Invasion ◽

Novel Target

BackgroundBladder cancer is one of the most common cancers all over the world. CircZFR is a circular RNA and has been implicated in tumor generation and invasion. However, the exact role of circZFR in the development of bladder cancer (BCa) remains unknown. This study aimed to investigate the function of circZFR in BCa, and further to probe into the association between circ-ZFR, miR-545/miR-1270 and WNT5A.MethodsThe expression of circZFR in BCa was quantified by qRT-PCR and was positively correlated with the prognosis of BCa patients. Next, the stable knockdown of circZFR BCa cell lines was established and the resulting capacities of proliferation, migration and invasion were measured. The association of circZFR with miR-1270/miR-545 was predicted by circinteractome prediction, and was confirmed by luciferase assay as well as RNA pull down assay. Furthermore, miRNA inhibitors, WNT5A overexpression and Pearson correlation analysis were used to examine the relationship between circZFR, miR-1270/miR-545 and WNT5A.ResultsThe expression of CircZFR was up-regulated both in BCa tissues and in BCa cell lines, and was positively correlated with patient survival rates. Blocking of circZFR’s expression by RNA inhibitors suppressed the proliferation, migration and invasion of BCa cells both in vitro and in vivo. On the other hand, overexpression of target miRNA supported that circZFR directly interact with miR-545 and miR-1270. Moreover, we demonstrated that circZFR promotes the progression of BCa by upregulating WNT5A’s expression via sponging miR-545 and miR-1270.ConclusionsCircZFR promotes the proliferation, migration and invasion of BCa cells by upregulating WNT5A signaling pathway via sponging miR-545 and miR-1270. These results provide new insights into the molecular mechanism of circZFR in BCa progression, and more important, a novel target for BCa clinical treatment.

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Circular RNA Circ-0006302 Promotes the Growth, Migration, and Invasion of Cholangiocarcinoma Cells by Regulating the Mir-1299/PD-L1 Axis as a Competing Endogenous RNA

10.21203/rs.3.rs-638620/v1 ◽

2021 ◽

Author(s):

Weiqian Chen ◽

Liyun Zheng ◽

Songquan Wu ◽

Chenying Lu ◽

Bufu Tang ◽

...

Keyword(s):

Epithelial To Mesenchymal Transition ◽

Circular Rna ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Circular Rnas ◽

Loss Of Function ◽

Mesenchymal Transition ◽

The Difference ◽

Gain Loss

Abstract Background: Cholangiocarcinoma (CCA) is an aggressive malignancy with a poor prognosis, with no effective therapy other than surgical resection. Circular RNAs (circRNAs) serve as a brand-new class of transcription products among abundant cancer processes. Nevertheless, the mechanisms account for their modification in CCA remain unknown. Methods: First, microarray sequencing was applied to detect the difference of circRNAs expression between CCA and corresponding non-tumor tissues. We utilized qRT-PCR to measure circ-0006302 levels in CCA cells and specimens. Gain/loss of-function assays and animal model of CCA were performed for the purpose of revealing the functions of circ-0006302 on the invasion, migration, and proliferation of CCA. We performed dual luciferase reporter, RNA-FISH and rescue assays for clarifying the mechanism behind. Results: In CCA tissues and cell lines circ-0006302 was highly expressed relatively. In vitro, overexpression of circ-0006302 intensifies the epithelial-to-mesenchymal transition (EMT) and the invasion, migration, and growth of CCA cells; and intensifies the growth as well as metastasis of tumors in a CCA mouse model. Furthermore, it was elucidated that circ-0006302 sponged miR-1299 to upregulate PD‐L1 expression. Through the process above, circ-0006302 binds to miR-1299 and emancipates PD-L1, facilitating the invasion, migration, and proliferation in CCA cells. Momentously, the results obtained revealed that circ-0006302 silencing elevated the expression of interferon (IFN)‐γ, and interleukin (IL)‐4 but diminished the IL-10 expression, while these effects could be reversed by miR-1299 inhibitor.Conclusion: circ-0006302 silence blocked the CCA progression via intensifying miR‐1299‐targeted downregulation of PD‐L1. Our conclusion provides novel therapeutic tactics for treating this fatal disease.

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The Circular RNA hsa_circ_0001445 Regulates the Proliferation and Migration of Hepatocellular Carcinoma and May Serve as a Diagnostic Biomarker

Disease Markers ◽

10.1155/2018/3073467 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 27

Author(s):

Xianwei Zhang ◽

Hu Zhou ◽

Wei Jing ◽

Ping Luo ◽

Shili Qiu ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Hepatitis B ◽

Characteristic Curve ◽

Circular Rna ◽

Migration And Invasion ◽

Circular Rnas ◽

Healthy Controls ◽

Polymerase Chain ◽

And Migration

Circular RNAs (circRNA), a class of noncoding RNAs, have been found to be involved in various diseases. Here, the expression levels of the circRNA hsa_circ_0001445 in 73 pairs of hepatocellular carcinoma (HCC) and adjacent nontumor tissues were investigated by quantitative real-time polymerase chain reaction (qRT-PCR). Our data demonstrate that the hsa_circ_0001445 levels were significantly decreased in HCC tissues (P<0.001) and markedly associated with the number of tumor foci (P=0.014). Furthermore, in vitro approaches showed that overexpression of hsa_circ_0001445 promoted apoptosis and inhibited proliferation, migration, and invasion of HCC-derived cells, suggesting that hsa_circ_0001445 might be involved in the development of HCC. In addition, we found that the plasma hsa_circ_0001445 transcription levels in HCC patients were lower than those in cirrhosis (P<0.001) and hepatitis B (P<0.001) patients as well as in healthy controls (P<0.001). In fact, receiver operating characteristic curve analysis indicated that plasma hsa_circ_0001445 could be a fairly accurate marker to distinguish HCC cases from healthy controls as well as patients with cirrhosis or hepatitis B.

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Circular RNA circ_0081001 knockdown enhances methotrexate sensitivity in osteosarcoma cells by regulating miR-494-3p/TGM2 axis

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-020-02169-5 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Wei Wei ◽

Liefeng Ji ◽

Wanli Duan ◽

Jiang Zhu

Keyword(s):

Cell Viability ◽

Xenograft Model ◽

Transglutaminase 2 ◽

Circular Rna ◽

Cell Counting ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Circular Rnas

Abstract Background Circular RNAs (circRNAs) have been shown to participate in the chemoresistance and tumorigenesis of multiple cancers. The purpose of this research was to investigate the function of circ_0081001 in methotrexate (MTX) resistance of osteosarcoma (OS) and its potential molecular mechanism. Methods The expression of circ_0081001, cytochrome P450 family 51 subfamily A member 1 (CYP51A1), and miR-494-3p was detected by qRT-PCR. Cell viability, apoptosis, migration, and invasion were evaluated by Cell Counting Kit-8 (CCK-8) assay, flow cytometry, and transwell assay, respectively. Western blot (WB) assay was used to measure the protein levels of cleaved-caspase3 (cleaved-casp3), E-cadherin, N-cadherin, and transglutaminase-2 (TGM2). The interaction between miR-494-3p and circ_0081001 or TGM2 was predicted by bioinformatics analysis and verified using the dual-luciferase reporter assay. The mice xenograft model was established to investigate the roles of circ_0081001 in MTX resistance of OS in vivo. Results Circ_0081001 and TGM2 were upregulated, and miR-494-3p was downregulated in MTX-resistant OS tissues and cells. Moreover, circ_0081001 interference enhanced cell sensitivity to MTX through promoting apoptosis and inhibiting cell viability and metastasis in vitro. Furthermore, circ_0081001 was identified as a molecular sponge of miR-494-3p to upregulate TGM2 level. In addition, circ_0081001 knockdown inhibited MTX resistance via upregulating miR-494-3p and downregulating TGM2. Besides, circ_0081001 downregulation improved MTX sensitivity of OS in vivo. Conclusion Knockdown of circ_0081001 enhanced MTX sensitivity of OS cells through downregulating TGM2 by sponging miR-494-3p, elucidating a novel regulatory mechanism for chemoresistance of OS and providing a potential circRNA-targeted therapy for OS.

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Circular RNA Circ-0002570 Accelerates Cancer Progression by Regulating VCAN via MiR-587 in Gastric Cancer

Frontiers in Oncology ◽

10.3389/fonc.2021.733745 ◽

2021 ◽

Vol 11 ◽

Author(s):

Lei Yang ◽

Yong-ning Zhou ◽

Miao-miao Zeng ◽

Nan Zhou ◽

Bin-sheng Wang ◽

...

Keyword(s):

Gastric Cancer ◽

Cancer Progression ◽

Circular Rna ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Circular Rnas ◽

Functional Roles ◽

Reporter Assays

BackgroundCircular RNAs (circRNAs) are closely associated with the occurrences and progress of gastric cancer (GC). We aimed to delve into the function and pathological mechanism of Circular RNA-0002570 (circ-0002570) in GC progression.MethodsCircRNAs differentially expressed in GC were screened using bioinformatics technology. The expression of circ-0002570 was detected in GC specimens and cells via qRT-PCR, and the prognostic values of circ-0002570 were determined. The functional roles of circ-0002570 on proliferation, migration, and invasion in GC cells were explored in vitro and in vivo. Interaction of circ-0002570, miR-587, and VCAN was confirmed by dual-luciferase reporter assays, Western blotting, and rescue experiments.ResultsCirc-0002570 expression was distinctly increased in GC tissues compared to adjacent normal specimens, and GC patients with higher circ-0002570 expressions displayed a short survival. Functionally, knockdown of circ-0002570 resulted in the inhibition of cell proliferation, migration, and invasion, and suppressed tumor growth in vivo. Mechanistically, miR-587 was sponged by circ-0002570. VCAN expression in NSCLC was directly inhibited by miR-587. Overexpression of circ-0002570 prevented VCAN from miR-587-mediated degradation and thus facilitated GC progression.ConclusionThe circ-0002570-miR-587-VCAN regulatory pathway promoted the progression of GC. Our findings provided potential new targets for the diagnosis and therapy of GC.

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Circular RNA hsa_circ_0000073 Enhances Osteosarcoma Cells Malignant Behavior by Sponging miR-1252-5p and Modulating CCNE2 and MDM2

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.714601 ◽

2021 ◽

Vol 9 ◽

Author(s):

Zhijing Ren ◽

Qinqin Yang ◽

Jiajia Guo ◽

Haifeng Huang ◽

Bo Li ◽

...

Keyword(s):

Cell Cycle ◽

Malignant Tumor ◽

Cell Function ◽

Circular Rna ◽

Tumor Promoter ◽

Luciferase Reporter ◽

Circular Rnas ◽

Novel Target

Objective: An increasing number of studies have demonstrated that circular RNAs (circRNAs) are involved in tumor progression. However, the role of hsa_circ_0000073 in osteosarcoma (OS) is still not fully elucidated.Methods: Quantitative reverse transcription-polymerase chain reaction or Western blot was used to detect the gene expression. GeneChip analysis, bioinformatics, luciferase reporter, and RNA immunoprecipitation assays were adopted to predict and verify the relationships between genes. Counting Kit-8 Assay, clone formation assay, wound-healing assay, transwell assays, cell cycle assays, and in vivo tumorigenesis were used to evaluate cell function.Results: hsa_circ_0000073 was highly expressed in OS cell lines and could promote OS progression, including proliferation, migration, invasion, and cell cycle in vitro as well as tumorigenesis in vivo. Mechanically, hsa_circ_0000073 could readily downregulate the expression of CCNE2 and MDM2 through miR-1252-5p. Rescue experiments validated miR-1252-5p mimics, or CCNE2/MDM2 short hairpin RNA could reverse the hsa_circ_0000073 overexpressing-induced impairment of malignant tumor behavior.Conclusion: hsa_circ_0000073 functions as a tumor promoter in OS to increase malignant tumor behavior through sponging miR-1252-5p and regulating CCNE2 and MDM2 expression, which could be a novel target for OS therapy.

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Circular RNA hsa_circ_0110389 promotes gastric cancer progression through upregulating SORT1 via sponging miR-127-5p and miR-136-5p

Cell Death and Disease ◽

10.1038/s41419-021-03903-5 ◽

2021 ◽

Vol 12 (7) ◽

Author(s):

Min Liang ◽

Wenxia Yao ◽

Boyun Shi ◽

Xiongjie Zhu ◽

Rui Cai ◽

...

Keyword(s):

Gastric Cancer ◽

Cancer Progression ◽

Circular Rna ◽

Migration And Invasion ◽

Circular Rnas ◽

Environmental Carcinogen ◽

Advanced Stages

AbstractIncreasing studies have found that circular RNAs (circRNAs) are aberrantly expressed and play important roles in the occurrence and development of human cancers. However, the function of circRNAs on environmental carcinogen-induced gastric cancer (GC) progression remains poorly elucidated. In the present study, hsa_circ_0110389 was identified as a novel upregulated circRNA in malignant-transformed GC cells through RNA-seq, and subsequent quantitative real-time PCR verified that hsa_circ_0110389 was significantly increased in GC tissues and cells. High hsa_circ_0110389 expression associates with advanced stages of GC and predicts poor prognosis. Knockdown and overexpression assays demonstrated that hsa_circ_0110389 regulates proliferation, migration, and invasion of GC cells in vitro. In addition, hsa_circ_0110389 was identified to sponge both miR-127-5p and miR-136-5p and SORT1 was validated as a direct target of miR-127-5p and miR-136-5p through multiple mechanism assays; moreover, hsa_circ_0110389 sponged miR-127-5p/miR-136-5p to upregulate SORT1 expression and hsa_circ_0110389 promoted GC progression through the miR-127-5p/miR-136-5p–SORT1 pathway. Finally, hsa_circ_0110389 knockdown suppressed GC growth in vivo. Taken together, our findings firstly identify the role of hsa_circ_0110389 in GC progression, which is through miR-127-5p/miR-136-5p–SORT1 pathway, and our study provides novel insight for the identification of diagnostic/prognostic biomarkers and therapeutic targets for GC.

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