CircMYOF triggers progression and facilitates glycolysis via the VEGFA/PI3K/AKT axis by absorbing miR-4739 in pancreatic ductal adenocarcinoma

AbstractEmerging evidence has demonstrated that circular RNAs (circRNAs) take part in the initiation and development of pancreatic ductal adenocarcinoma (PDA), a deadly neoplasm with an extremely low 5-year survival rate. Reprogrammed glucose metabolism is a key feature of tumour development, including PDA. In this research, we evaluated the role of circRNAs in reprogrammed glucose metabolism in PDA. RNA sequencing under various glucose incubation circumstances was performed. A new circMYOF was identified. Sanger sequencing and RNase R treatment confirmed its circular RNA characteristics. Real-time PCR indicated that it was highly expressed in PDA clinical specimens and cell lines. Gain-of- and loss-of-function assays showed that circMYOF induced progression in PDA. Mechanistically, RNA pull-down and luciferase reporter experiments elucidated that circMYOF, as a competing endogenous RNA for miR-4739, facilitated glycolysis via the VEGFA/PI3K/AKT pathway. Taken together, our findings indicate that circMYOF may work as a desirable biomarker and therapeutic target for PDA patients.

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Circular RNA CircEYA3 induces energy production to promote pancreatic ductal adenocarcinoma progression through the miR-1294/c-Myc axis

Molecular Cancer ◽

10.1186/s12943-021-01400-z ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Zeyin Rong ◽

Si Shi ◽

Zhen Tan ◽

Jin Xu ◽

Qingcai Meng ◽

...

Keyword(s):

Pancreatic Ductal Adenocarcinoma ◽

Energy Production ◽

Atp Synthesis ◽

Circular Rna ◽

Gene Expression Omnibus ◽

Ductal Adenocarcinoma ◽

Luciferase Reporter ◽

Circular Rnas

Abstract Background Extensive studies have demonstrated the pivotal roles of circular RNAs (circRNAs) in the occurrence and development of different human cancers. However, the expression and regulatory roles of circRNAs in pancreatic ductal adenocarcinoma (PDAC) are unclear. Methods CircEYA3 was explored based on Gene Expression Omnibus (GEO) dataset analysis. qRT-PCR was applied to determine the expression of circRNAs, miRNAs and mRNAs in PDAC cells and tissues. The biological roles of circEYA3 in vitro and in vivo were determined by performing a series of functional experiments. Further, dual luciferase reporter, fluorescence in situ hybridization (FISH), RNA pull-down assays, and RNA immunoprecipitation (RIP) assays were used to confirm the interaction of circEYA3 with miR-1294. Results CircEYA3 was elevated in PDAC tissues and cells, and a higher level of circEYA3 was significantly associated with a poorer prognosis in patients with PDAC. Functionally, circEYA3 increased energy production via ATP synthesis to promote PDAC progression in vitro and in vivo. Mechanistically, circEYA3 functions as an endogenous miR-1294 sponge to elevate c-Myc expression, thus exerting its oncogenic functions. Conclusion CircEYA3 promotes the progression of PDAC through the miR-1294/c-Myc signalling axis, and circEYA3 may be an efficient molecular therapeutic target in PDAC.

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Hsa_circ_0026628 promotes the development of colorectal cancer by targeting SP1 to activate the Wnt/β-catenin pathway

Cell Death and Disease ◽

10.1038/s41419-021-03794-6 ◽

2021 ◽

Vol 12 (9) ◽

Author(s):

Xuexiu Zhang ◽

Jianning Yao ◽

Haoling Shi ◽

Bing Gao ◽

Haining Zhou ◽

...

Keyword(s):

Colorectal Cancer ◽

Transcription Factor ◽

Circular Rna ◽

Luciferase Reporter ◽

Circular Rnas ◽

Transcriptional Level ◽

Sp1 Transcription Factor ◽

Reporter Assays ◽

Sphere Formation

AbstractCircular RNAs (circRNAs) have been reported to play crucial roles in the progression of various cancers, including colorectal cancer (CRC). SP1 (Sp1 transcription factor) is a well-recognized oncogene in CRC and is deemed to trigger the Wnt/β-catenin pathway. The present study was designed to investigate the role of circRNAs which shared the same pre-mRNA with SP1 in CRC cells. We identified that hsa_circ_0026628 (circ_0026628), a circular RNA that originated from SP1 pre-mRNA, was upregulated in CRC cells. Sanger sequencing and agarose gel electrophoresis verified the circular characteristic of circ_0026628. Functional assays including CCK-8, colony formation, transwell, immunofluorescence staining, and sphere formation assay revealed the function of circ_0026628. RNA pull-down and mass spectrometry disclosed the proteins interacting with circ_0026628. Mechanistic assays including RIP, RNA pull-down, CoIP, ChIP, and luciferase reporter assays demonstrated the interplays between molecules. The results depicted that circ_0026628 functioned as a contributor to CRC cell proliferation, migration, EMT, and stemness. Mechanistically, circ_0026628 served as the endogenous sponge of miR-346 and FUS to elevate SP1 expression at the post-transcriptional level, thus strengthening the interaction between SP1 and β-catenin to activate the Wnt/β-catenin pathway. In turn, the downstream gene of Wnt/β-catenin signaling, SOX2 (SRY-box transcription factor 2), transcriptionally activated SP1 and therefore boosted circ_0026628 level. On the whole, SOX2-induced circ_0026628 sponged miR-346 and recruited FUS protein to augment SP1, triggering the downstream Wnt/β-catenin pathway to facilitate CRC progression.

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A Novel Circular RNA CircRFX3 Serves as a Sponge for MicroRNA-587 in Promoting Glioblastoma Progression via Regulating PDIA3

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.757260 ◽

2021 ◽

Vol 9 ◽

Author(s):

Tong Li ◽

Jianguo Xu ◽

Yi Liu

Keyword(s):

Circular Rna ◽

Molecular Therapy ◽

Luciferase Reporter ◽

Circular Rnas ◽

Competing Endogenous Rna ◽

Luciferase Reporter Gene ◽

Invasion And Migration ◽

Downstream Target ◽

Novel Target ◽

And Migration

An increasing number of studies have indicated that circular RNAs (circRNAs) participate in the progression of numerous tumors. However, the functions of circRNAs in glioblastoma (GBM) remain largely unknown. In this study, we focused on a novel circRNA (hsa_circRFX3_003) that was spliced from RFX3, which we named circRFX3. We confirmed that the expression of circRFX3 was substantially increased in GBM cell lines and clinical GBM tissues. The results of a series of overexpression and knockdown assays indicated that circRFX3 could boost the proliferation, invasion, and migration of GBM cells. By performing dual-luciferase reporter gene and RNA pull-down assays, we verified that circRFX3 could sponge microRNA-587 (miR-587) to exercise its function as a competing endogenous RNA (ceRNA) in the development of GBM. In addition, PDIA3 was proven to be a downstream target of miR-587 and to regulate the Wnt/β-catenin pathway. In conclusion, circRFX3 could act as a cancer-promoting circRNA to boost the development of GBM and regulate the miR-587/PDIA3/β-catenin axis. This study might provide a novel target for the treatment of GBM with molecular therapy.

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Circ0120816 Acts As An Oncogene of Esophageal Squamous Cell Carcinoma via Inhibiting miR-1305 and Releasing TXNRD1

10.21203/rs.3.rs-47889/v1 ◽

2020 ◽

Author(s):

Xiaoyong Li ◽

Laichun Song ◽

Bo Wang ◽

Chao Tao ◽

Lei Shi ◽

...

Keyword(s):

Squamous Cell Carcinoma ◽

Esophageal Squamous Cell Carcinoma ◽

Cell Carcinoma ◽

Squamous Cell ◽

Caspase 3 ◽

Luciferase Reporter ◽

Circular Rnas ◽

Rnase R ◽

Rna Immunoprecipitation

Abstract Background: The morbidity and mortality of esophageal squamous cell carcinoma (ESCC) remains stubbornly high, in spite of emerging new diagnoses methods. The role of circular RNAs (circRNAs) in ESCC progression is still in need of more exploration. Methods: In this research, we gathered 36 patients’ ESCC tissues to analyze the expression of circ0120816, miR-1305 and TXNRD1. KYSE450 and KYSE510 cells were used to conduct the transfection. Aiming to verify our hypothesis, qRT-PCR, RNase R treatment, nuclear extraction, luciferase reporter assay, RNA immunoprecipitation assay, CCK-8, BrdU, cell adhesion, caspase 3 activity assay were used. Results: Circ0120816, upregulated in ESCC, acted as a sponge for miR-1305. Circ0120816 combined miR-1305 to enhance cell viability, proliferation adhesion and repress cell apoptosis in ESCC cell lines. On the contrary, miR-1305 exerted reversed effect in ESCC cells through decreasing TXNRD1. Conclusions: This research demonstrated that circ0120816 promoted ESCC development by competitive binding miR-1305 which could increase the expression of TXNRD1.

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FUS-induced circRHOBTB3 facilitates cell proliferation via miR-600/NACC1 mediated autophagy response in pancreatic ductal adenocarcinoma

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-021-02063-w ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Taoyue Yang ◽

Peng Shen ◽

Qun Chen ◽

Pengfei Wu ◽

Hao Yuan ◽

...

Keyword(s):

Cell Proliferation ◽

Pancreatic Ductal Adenocarcinoma ◽

Cell Lines ◽

Rna Binding ◽

Ductal Adenocarcinoma ◽

Luciferase Reporter ◽

Circular Rnas ◽

Pdac Cell

Abstract Background Circular RNAs (circRNAs) are becoming a unique member of non-coding RNAs (ncRNAs) with emerging evidence of their regulatory roles in various cancers. However, with regards to pancreatic ductal adenocarcinoma (PDAC), circRNAs biological functions remain largely unknown and worth investigation for potential therapeutic innovation. Methods In our previous study, next-generation sequencing was used to identify differentially expressed circRNAs in 3 pairs of PDAC and adjacent normal tissues. Further validation of circRHOBTB3 expression in PDAC tissues and cell lines and gain-and-loss function experiments verified the oncogenic role of circRHOBTB3. The mechanism of circRHOBTB3 regulatory role was validated by pull-down assays, RIP, luciferase reporter assays. The autophagy response of PANC-1 and MiaPaca-2 cells were detected by mCherry-GFP-LC3B labeling and confocal microscopy, transmission electron microscopy and protein levels of LC3B or p62 via Western blot. Results circRHOBTB3 is highly expressed in PDAC cell lines and tissues, which also promotes PDAC autophagy and then progression in vitro and in vivo. Mechanistically, circRHOBTB3 directly binds to miR-600 and subsequently acts as a miRNA-sponge to maintain the expression level of miR-600-targeted gene NACC1, which facilitates the autophagy response of PDAC cells for adaptation of proliferation via Akt/mTOR pathway. Moreover, the RNA-binding protein FUS (FUS) directly binds to pre-RHOBTB3 mRNA to mediate the biogenesis of circRHOBTB3. Clinically, circRHOBTB3, miR-600 and NACC1 expression levels are correlated with the prognosis of PDAC patients and serve as independent risk factors for PDAC patients. Conclusions FUS-mediated circRHOBTB3 functions as a tumor activator to promote PDAC cell proliferation by modulating miR-600/NACC1/Akt/mTOR axis regulated autophagy.

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Circular RNA Expression Profile of Pancreatic Ductal Adenocarcinoma Revealed by Microarray

Cellular Physiology and Biochemistry ◽

10.1159/000453186 ◽

2016 ◽

Vol 40 (6) ◽

pp. 1334-1344 ◽

Cited By ~ 57

Author(s):

Haimin Li ◽

Xiaokun Hao ◽

Huimin Wang ◽

Zhengcai Liu ◽

Yong He ◽

...

Keyword(s):

Pancreatic Ductal Adenocarcinoma ◽

Expression Profile ◽

Mammalian Cells ◽

Noncoding Rna ◽

Circular Rna ◽

Pathological Process ◽

Ductal Adenocarcinoma ◽

Circular Rnas ◽

Normal Tissues ◽

Polymerase Chain

Background/Aims: Circular RNAs (circRNAs) are a special novel type of a stable, diverse and conserved noncoding RNA in mammalian cells. Particularly in cancer, circRNAs have been reported to be widely involved in the physiological/pathological process of life. However, it is unclear whether circRNAs are specifically involved in pancreatic ductal adenocarcinoma (PDAC). Methods: We investigated the expression profile of circRNAs in six PDAC cancer samples and paired adjacent normal tissues using microarray. A high-throughput circRNA microarray was used to identify dysregulated circular RNAs in six PDAC patients. Bioinformatic analyses were applied to study these differentially expressed circRNAs. Furthermore, quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to confirm these results. Results: We revealed and confirmed that a number of circRNAs were dysregulated, which suggests a potential role in pancreatic cancer. Conclusions: this study demonstrates that clusters of circRNAs are aberrantly expressed in PDAC compared with normal samples and provides new potential targets for the future treatment of PDAC and novel insights into PDAC biology.

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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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Circular RNA circASPM Promotes the Progression of Glioblastoma by Acting as a Competing Endogenous RNA to Regulate miR-130b–3p/E2F1 Axis

10.21203/rs.3.rs-132678/v1 ◽

2020 ◽

Author(s):

Dianqi Hou ◽

Zhenlin Wang ◽

Haimeng Li ◽

Juan Liu ◽

Yaohua Liu ◽

...

Keyword(s):

Western Blotting ◽

Circular Rna ◽

Luciferase Reporter ◽

Circular Rnas ◽

Primary Malignancy ◽

Rna Immunoprecipitation ◽

Western Blotting Assay

Abstract background: Glioblastoma Multiform (GBM) is the primary malignancy with the highest incidence and worst prognosis in the adult CNS. Circular RNAs (circRNAs) are a novel and widely diverse class of endogenous non-coding RNAs that can promote or inhibit gliomagenesis. Our study aimed to explore the role of circASPM in GBM and its molecular mechanism.Methods: Levels of circASPM, miR-130b-3p and E2F1 were determined by quantitative real-time PCR (qRT-PCR) or western blotting assay. MTS, Edu, neurospheres formation and extreme limiting dilution assays were used to detect the tumorigenesis and proliferation of GSCs in vitro. The interactions between miR-130b-3p and circASPM or E2F1 was demonstrated via qPCR, western blotting, dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Xenograft experiments was used to analyze tumor growth in vivo.Results: CircASPM was overexpressed in GBM and could promote the tumorigenesis and proliferation of GSCs both in vitro and in vivo. Mechanistically, circASPM up-regulated the expression of E2F1 in GSCs via miR-130b-3p sponging. We furtherly demonstrated that circAPSM could promote the GSCs proliferation via E2F1 up-regulating. Therefore, our study identified a novel circRNA and its possible mechanism in the development and tumorigenesis of GBM.Conclusions: CircASPM can promote GBM progression via regulating miR-130b-3p/E2F1 axis, suggesting that circAPSM could provide an effective biomarker for GBM diagnosis and prognostic evaluation and possibly being used for molecular targeted therapy.

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Exosomal circRNAs: new players in the field of cholangiocarcinoma

Clinical Science ◽

10.1042/cs20190940 ◽

2019 ◽

Vol 133 (21) ◽

pp. 2239-2244 ◽

Cited By ~ 3

Author(s):

Corentin Louis ◽

Matthis Desoteux ◽

Cédric Coulouarn

Keyword(s):

Cell Lines ◽

Molecular Mechanisms ◽

Human Tumor ◽

Direct Interaction ◽

Circular Rna ◽

Circular Rnas ◽

Loss Of Function ◽

Non Invasive ◽

Tumor Tissues

Abstract Cholangiocarcinoma (CCA) is a deadly cancer worldwide associated with limited therapeutic options. A recent study published in Clinical Science by Wang and colleagues [Clin. Sci. (2019) 133(18), 1935–1953] brought new perspectives to CCA management and therapy by focusing on circular RNAs (circRNAs). CircRNAs belong to an emerging class of functional non-coding RNAs (ncRNAs) regulating numerous biological processes. Notably, circRNAs have been associated with cancer onset and progression, although reports in CCA are very limited so far. In this work, the expression of circular RNA circ-0000284 (aka circHIPK3) was specifically elevated in CCA cell lines, human tumor tissues and plasma exosomes. Gain and loss of function approaches were performed to better understand the molecular mechanisms regulated by circ-0000284. Notably, the authors evaluated the role of circ-0000284 as a microRNA (miRNA) sponge. By prediction analysis and functional tests, a direct interaction was demonstrated with miR-637 that targets lymphocyte antigen-6 E (LY6E). Increased expression of circ-0000284 was associated with enhanced migration, invasion and proliferation of CCA cell lines. Interestingly, exosomal-mediated circ-0000284 was reported to exhibit pro-oncogenic effects on surrounding normal cells. Altogether, these data highlight circRNAs not only as new players in CCA pathogenesis but also as promising molecules for innovative non-invasive biomarkers, as circRNAs are enriched and stable in exosomes. Further investigations on extracellular vesicles should provide the necessary tools to improve CCA diagnosis, and move toward targeted-therapies.

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Circular RNA hsa_Circ_101141 as a Competing Endogenous RNA Facilitates Tumorigenesis of Hepatocellular Carcinoma by Regulating miR-1297/ROCK1 Pathway

Cell Transplantation ◽

10.1177/0963689720948016 ◽

2020 ◽

Vol 29 ◽

pp. 096368972094801 ◽

Cited By ~ 1

Author(s):

Tao Zhang ◽

Lijuan Zhang ◽

Dan Han ◽

Kebinur Tursun ◽

Xiaobo Lu

Keyword(s):

Hepatocellular Carcinoma ◽

Coiled Coil ◽

Circular Rna ◽

Migration And Invasion ◽

Circular Rnas ◽

Competing Endogenous Rna ◽

Direct Target ◽

And Function

As a novel class of noncoding RNAs, circular RNAs (circRNAs) have been recently reported to be involved in cell development and function. However, the functional role of circRNAs in hepatocellular carcinoma (HCC) remains unclear. In the present study, we found that the expression of human circ_101141 was upregulated in HCC tissues and cells. In addition, downregulation of circ_101141 dramatically inhibited cell proliferation, migration, and invasion in HCC cells. In addition, by using the bioinformatics tools, the potential target of circ_101141 was predicted. Mechanistic investigations indicated that circ_101141 acted as a miR-1297 “sponge”; meanwhile, Rho-associated, coiled-coil-containing protein kinase 1 (ROCK1) was a direct target of miR-1297. Further experiments demonstrated that circ_101141 contributed to the progression of HCC by acting as competing endogenous RNA (ceRNA) of miR-1297 to regulate ROCK1 expression. Furthermore, knockdown of circ_101141 attenuated HCC tumorigenesis in vivo. Taken together, these findings indicated that circRNA circ_101141 acted as a ceRNA to facilitate tumorigenesis of HCC by regulating miR-1297/ROCK1 pathway.

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