Analysis of ceRNA network identifies prognostic circRNA biomarkers in bladder cancer

circCD2AP promotes epithelial mesenchymal transition and stemness in bladder cancer by regulating FOXQ1/USP21 axis

Bladder cancer (BC) is a prevalent and deadly disease. circCD2AP was suggested to be highly expressed in BC. However, the exact mechanism needs further investigation. In this study, circCD2AP was observed to be upregulated in BC and linked to poor prognosis in individuals. Functionally, circCD2AP or USP21 knockdown inhibited BC cell EMT and stemness both in vitro and in vivo. Mechanistically, circCD2AP interacted with ELAVL1 to enhance the stability of USP21 mRNA, which, in turn, inhibited the ubiquitination degradation of FOXQ1. Through rescue assay, USP21 or FOXQ1 knockdown was found to abolish the promoting effects of circCD2AP or USP21 overexpression on BC cell EMT and stemness. Overall, this study has unveiled the role of circCD2AP/ELAVL1/USP21/FOXQ1 axis in BC EMT and stemness regulation, offering insights into the mechanisms underlying BC progression, with potential implications for therapeutic strategies.

Urine biomarkers in bladder cancer - current status and future perspectives

Urine markers to detect bladder cancer have been the subject of research for decades. The idea that urine - being in continuous contact with tumour tissue - should provide a vector of tumour information remains an attractive concept. Research on this topic has resulted in a complex landscape of many different urine markers with varying degrees of clinical validation. These markers range from cell-based assays to proteins, transcriptomic markers and genomic signatures, with a clear trend towards multiplex assays. Unfortunately, the number of different urine markers and the efforts in research and development of clinical grade assays are not reflected in the use of these markers in clinical practice, which is currently limited. Numerous prospective trials are in progress with the aim of increasing the quality of evidence about urinary biomarkers in bladder cancer to achieve guideline implementation. The current research landscape suggests a division of testing approaches. Some efforts are directed towards addressing the limitations of current assays to improve the performance of urine markers for a straightforward detection of bladder cancer. Additionally, comprehensive genetic analyses are emerging based on advances in next-generation sequencing and are expected to substantially affect the potential application of urine markers in bladder cancer.

Circular RNA hsa_circ_0000915 promotes propranolol resistance of hemangioma stem cells in infantile haemangiomas

BACKGROUND

Propranolol is a first-line clinical drug for infantile haemangiomas (IH) therapy. Nevertheless, resistance to propranolol is observed in some patients with IH. Circular RNAs (circRNAs) has been increasingly reported to act as a pivotal regulator in tumor progression. However, the underlying mechanism of circRNAs in IH remains unclear.

METHODS

Quantitative real-time polymerase chain reaction was performed to detect Circ_0000915, miR-890 and RNF187 expression. Protein levels were determined using western blot. CCK-8 assay was used to measure cell proliferation. Caspase-3 activity assay and flow cytometry were conducted to determine cell apoptosis. Luciferase reporter assay was carried out to assess the interaction between miR-890 and Circ_0000915 or RNF187. Chromatin immunoprecipitation assay was performed to detect the interaction between STAT3 and Circ_0000915 promoter. Biotin pull-down assay was used to detect the direct interaction between miR-890 and Circ_0000915. In vivo experiments were performed to measure tumor formation.

RESULTS

Here, we discovered depletion of Circ_0000915 increased propranolol sensitivity of haemangioma derived stem cells (HemSCs) both in vitro and in vivo, whereas forced expression of Circ_0000915 exhibited opposite effects. Mechanistically, Circ_0000915, transcriptionally induced by IL-6/STAT3 pathway, competed with RNF187 for the biding site in miR-890, led to upregulation of RNF187 by acting as a miR-890 "sponge". Furthermore, silence of miR-890 reversed increased propranolol sensitivity of HemSCs due to Circ_0000915 ablation. Moreover, increased Circ_0000915 and RNF187 levels were observed in IH tissues and positively associated with propranolol resistance, miR-890 exhibited an inverse expression pattern.

CONCLUSION

We thereby uncover the activation of IL-6/STAT3/Circ_0000915/miR-890/RNF187 axis in propranolol resistance of IH, and provide therapeutic implications for patients of IH with propranolol resistance.

Inhibition of MIR4435-2HG on Invasion, Migration, and EMT of Gastric Carcinoma Cells by Mediating MiR-138-5p/Sox4 Axis

Background

The previous investigations have identified that long non-coding RNA (lncRNAs) act as crucial regulators in gastric carcinoma. However, the function of lncRNA MIR4435-2HG in the modulation of gastric carcinoma remains elusive. Here, we aimed to explore the role of MIR4435-2HG in gastric carcinoma.

Method

The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were applied to select the differently expressed lncRNAs in gastric carcinoma. The qRT-PCR was applied to analyze MIR4435-2HG expression in carcinoma tissues and cell lines. The effect of MIR4435-2HG on proliferation, invasion, migration, and apoptosis of gastric carcinoma cells was detected by Cell Counting Kit-8 (CCK-8) assays, transwell assays, and flow cytometry in vitro. A subcutaneous tumor model was constructed to examine the tumor growth of gastric carcinoma cells after knocking out MIR4435-2HG. RNA immunoprecipitation and luciferase reporting assays were applied to evaluate the interaction of MIR4435-2HG, miR-138-5p, and Sox4.

Results

The bioinformatics analysis based on TCGA and GEO databases indicated that MIR4435-2HG was obviously elevated in gastric carcinoma samples. The qRT-PCR analysis revealed that MIR4435-2HG was upregulated in clinical gastric carcinoma tissues and cells. The high expression of MIR4435-2HG is associated with the poor survival rate of patients. The knockout of MIR4435-2HG could repress the proliferation, invasion, migration, and epithelial–mesenchymal transition (EMT) and accelerate the apoptosis of gastric carcinoma cells. Moreover, the deletion of MIR4435-2HG was able to attenuate the tumor growth in vivo. Mechanically, we identified that MIR4435-2HG enhanced Sox4 expression by directly interacting with miR-138-5p as a competitive endogenous RNA (ceRNA) in gastric carcinoma cells, in which Sox4 was targeted by miR-138-5p.

Conclusion

MIR4435-2HG is elevated in gastric carcinoma cells and contributes to the growth, metastasis, and EMT of gastric carcinoma cells by targeting miR-138-5p/Sox4 axis. MIR4435-2HG may be applied as a potential therapeutic target in gastric carcinoma.

Mediation of circ_RPPH1 on miR-146b-3p/E2F2 pathway to hinder the growth and metastasis of breast carcinoma cells

BACKGROUND

Nova Circular RNA (circRNA) of non-coding RNA has gradually become an important regulatory factor, and it has made people attach great concern over the occurrence and development of many diseases, particularly carcinomas. circ_RPPH1 is a newly discovered circRNA. Gene Expression Omnibus (GEO) analysis showed that there are high contents of circ_RPPH1 in breast cancer (BC), but the mechanism of circRNA in BC remains unclear.

METHODS

Real-time quantitative PCR (qRT-PCR) was applied to test the role of circ_RPPH1 in BC patients, and functional experiments were applied to test the role of circ_RPPH1 on BC tumor. Fluorescence in situ hybridization, double luciferase reporter gene analysis, RNA pull-down and RNA immunoprecipitation experiments were performed to explore the correlation of circ_RPPH1 with miR-146b-3p/E2F2 in BC.

RESULTS

circ_RPPH1 was evidently enhanced in BC, and its content was related to the clinical stage and pathological grade. circ_RPPH1 can accelerate the proliferation, migration and invasion, and promote tumorigenesis and metastasis. Mechanism exploration indicated that circ_RPPH1 acted as ceRNA (competing endogenous RNA) of miR-146b-3p, so as to reduce the inhibitory role of miR-146b-3p on its target E2F2.

CONCLUSION

Circ_RPPH1/miR-146b-3p/E2F2 axis can promote the progression of BC, and it might be a latent therapeutic target for clinical BC.

Grape Seed Proanthocyanidins (GSPs) Inhibit the Development of Cutaneous Squamous Cell Carcinoma by Regulating the hsa_circ_0070934/miR-136-5p/PRAF2 Axis

Background

Grape seed proanthocyanidins (GSPs) have been shown to inhibit the progression of many cancers, including cutaneous squamous cell carcinoma (CSCC). Circular RNA (circRNA) is a key regulator for cancer progression. However, it is unclear whether GSPs can mediate the progression of CSCC by regulating circRNA.

Methods

Quantitative real-time PCR was conducted to determine the expression of hsa_circ_0070934, microRNA (miR)-136-5p and prenylated Rab acceptor family 2 (PRAF2). MTT assay and colony formation assay were used to assess cell proliferation. Cell cycle process and apoptosis were detected by flow cytometry, and cell migration and invasion were measured by transwell assay. Western blot analysis was utilized to examine protein expression. In addition, dual-luciferase reporter assay and RIP assay were used to evaluate the interaction between miR-136-5p and hsa_circ_0070934 or PRAF2. Subcutaneous xenograft models were constructed to explore the function of GSPs on CSCC tumor growth in vivo.

Results

GSPs could reduce hsa_circ_0070934 expression and inhibit CSCC cell proliferation, cell cycle process, migration, invasion, while promote apoptosis. Overexpressed hsa_circ_0070934 could reverse the suppressive effect of GSPs on CSCC cell progression. MiR-136-5p could be sponged by hsa_circ_0070934, and its overexpression also abolished the positively regulation of hsa_circ_0070934 on the progression of GSPs-induced CSCC cells. PRAF2 was a target of miR-136-5p, and its expression could be decreased by GSPs and increased by hsa_circ_0070934. The inhibitory effect of miR-136-5p on CSCC cell progression could be reversed by PRAF2 overexpression. Additionally, GSPs also could inhibit CSCC tumor growth in vivo.

Conclusion

Our data showed that GSPs regulated the hsa_circ_0070934/miR-136-5p/PRAF2 axis to restrain CSCC progression.

Trends in urine biomarker discovery for urothelial bladder cancer: DNA, RNA, or protein?

Urothelial bladder cancer is a complex disease displaying a landscape of heterogenous molecular subtypes, mutation profiles and clinical presentations. Diagnosis and surveillance rely on flexible cystoscopy which has high accuracy, albeit accompanied by a high-cost burden for healthcare providers and discomfort for patients. Advances in "omic" technologies and computational biology have provided insights into the molecular pathogenesis of bladder cancer and provided powerful tools to identify markers for disease detection, risk stratification, and predicting responses to therapy. To date, numerous attempts have been made to discover and validate diagnostic biomarkers that could be deployed as an adjunct to the cystoscopic diagnosis and long-term surveillance of bladder cancer. We report a comprehensive literature analysis using PubMed to assess the changing trends in investigating DNA, RNA, or proteins as diagnostic urinary biomarkers over a period of 5 decades: 1970-2020. A gradual shift has been observed in research away from protein biomarkers to nucleic acids including different classes of RNA, and DNA methylation and mutation markers. Until 2000, publications involving protein biomarker discovery constituted 87% of the total number of research articles with DNA comprising 6% and RNA 7%. Since 2000 the proportion of protein biomarker articles has fallen to 40%, and DNA and RNA studies increased to 32% and 28%, respectively. Clearly research focus, perhaps driven by technological innovation, has shifted from proteins to nucleic acids. We optimistically hypothesise that, following thorough validation, a clinically useful detection test for bladder cancer based on a panel of DNA or RNA markers could become reality within 5-10 years.

Identification of circRNA-miRNA-mRNA Regulatory Network in Bladder Cancer by Integrated Analysis

INTRODUCTION

Bladder cancer (BC) is a common malignant tumor in the urinary system with high mortality and recurrence rates. This study sought to identify crucial circular RNAs (circRNAs) associated with BC.

METHODS

The mRNA, miRNA, and circRNA expression profiles of BC were downloaded from GEO database. The differentially expressed mRNAs (DEmRNAs), miRNAs (DEmiRNAs), and circRNAs (DEcircRNAs) were identified using bioinformatics method. Combining circRNA-miRNA pairs with miRNA-mRNA pairs, the competing endogenous RNA (ceRNA; DEcircRNA-DEmi-RNA-DEmRNA) regulatory network was constructed. Functional annotation of host gene of DEcircRNAs and DEmRNAs in ceRNA regulatory network were performed. qRT-PCR validation was performed.

RESULTS

A total of 4,003 DEmRNAs, 25 DEmiRNAs, and 119 DEcircRNAs were obtained. The ceRNA network contained 18 circRNA-miRNA pairs and 699 mi-RNA-mRNA pairs, including 17 circRNAs, 4 miRNAs, and 624 mRNAs. Functional annotation of DEmRNAs in ceRNA regulatory network revealed that these DEmRNAs were significantly enriched in glycerolipid metabolism, p53 signaling pathway, and oocyte meiosis. Except for hsa_circ_0028173, expression of the others in the qRT-PCR results was consistent with that in our integrated analysis, generally.

CONCLUSION

We speculate that hsa_circ_0008035/hsa-miR-107/MSRB3 and hsa_circ_0028173/hsa-miR-338-3p/TPX2/GATA3 interaction pairs may play a vital role in BC.

CircPPP1R12A promotes the progression of colon cancer through regulating CTNNB1 via sponging miR-375

Circular RNAs (circRNAs) have been identified as potential biomarkers for many cancer, including colon cancer (CC). However, the function and mechanism of circPPP1R12A in CC have not been fully elucidated. Quantitative real-time PCR was employed to assess the expression of circPPP1R12A, microRNA (miR)-375 and catenin beta-1 (CTNNB1). The proliferation, apoptosis, migration and invasion of cells were determined using colony formation assay, flow cytometry, wound healing assay and transwell assay. The protein levels of cell cyclin-related markers and CTNNB1 were detected by western blot analysis. The interaction between miR-375 and circPPP1R12A or CTNNB1 was verified by dual-luciferase reporter assay. Xenograft models were built to evaluate the effect of circPPP1R12A silencing and CTNNB1 overexpression on CC tumor growth in vivo. Our results showed that circPPP1R12A was a highly expressed circRNA in CC tissues and cells. Silenced circPPP1R12A suppressed the proliferation, promoted the apoptosis, and inhibited the migration and invasion of CC cells. MiR-375 could be sponged by circPPP1R12A, and its inhibitor could reverse the inhibition of circPPP1R12A silencing on CC progression. Furthermore, CTNNB1 was a target of miR-375, and its overexpression also abolished the suppression of miR-375 on CC progression. Moreover, circPPP1R12A indirectly regulated CTNNB1 expression by sponging miR-375. Importantly, circPPP1R12A knockdown reduced the tumor growth of CC in vivo, and this effect also could be reversed by overexpressing CTNNB1. Our study proposed that circPPP1R12A might play an oncogenic role in CC, which could act as a potential therapeutic target for CC.

circ_100984-miR-432-3p axis regulated c-Jun/YBX-1/β-catenin feedback loop promotes bladder cancer progression

Bladder cancer (BC) is one of the most commonly diagnosed cancers globally. Recently, circular RNAs (circRNAs) have been revealed to participate in BC progression with diverse mechanisms. However, mechanisms of circ_100984 in BC have not been determined. Here, we found that circ_100984 and YBX‐1 were high presented, while miR‐432‐3p was low presented in BC. Silencing of circ_100984 and YBX‐1 repressed BC tumor growth, migration, and invasion in vitro and in vivo. Mechanistically, we revealed that circ_100984 served as a competing endogenous RNA that sponged miR‐432‐3p to indirectly regulate YBX‐1 and epithelial‐mesenchymal transition (EMT)‐related molecules. Moreover, we confirmed that YBX‐1 or c‐Jun acted as a transcription regulatory factor for β‐catenin or YBX‐1, respectively, in BC cells. Knockdown of YBX‐1 inhibited the expression of β‐catenin and c‐Jun, whereas downregulated c‐Jun inversely repressed the expression of YBX‐1 and β‐catenin. Our results suggested that circ_100984‐miR‐432‐3p axis regulated c‐Jun/YBX‐1/β‐catenin feedback loop promotes BC progression, providing a potential therapeutic axis for BC progression.

Circular RNA RBPMS inhibits bladder cancer progression via miR-330-3p/RAI2 regulation

Bladder cancer is a severe cancer with high mortality because of invasion and metastasis. Growing evidence has revealed that circular RNAs play critical roles in biological function, which is closely connected to proliferation and invasion of bladder cancer. In our study, we employed qRT-PCR, RNA fluorescence in situ hybridization (FISH), 5-ethynyl-2′-deoxyuridine (EdU), CCK-8, Transwell assays, luciferase reporter assays, xenografts, and live imaging to detect the roles of circular RNA binding protein with multiple splicing (circRBPMS) in bladder cancer (BC). Bioinformatics analysis and WB were performed to investigate the regulatory mechanism. Expression profile analysis of circular RNAs (circRNAs) in BC revealed that circRBPMS was significantly downregulated. Low circRBPMS expression correlates with aggressive BC phenotypes, whereas upregulation of circRBPMS suppresses BC cell proliferation and metastasis by directly targeting the miR-330-3p/ retinoic acid induced 2 (RAI2) axis. miR-330-3p upregulation or silencing of RAI2 restored BC cell proliferation, invasion, and migration following overexpression of circRBPMS. RAI2 silencing reversed miR-330-3p-induced cell invasion and migration as well as growth inhibition in vitro. Moreover, through bioinformatic analysis of the downstream target of RAI2 in the TCGA database, we identified and validated the biological role of circRBPMS through the RAI2-mediated ERK and epithelial-mesenchymal transition (EMT) pathways. We summarize the circRBPMS/miR-330-3p/RAI2 axis, where circRBPMS acts as a tumor suppressor, and provide a potential biomarker and therapeutic target for BC.

CircRNAs: Emerging Bladder Cancer Biomarkers and Targets

Circular RNAs (circRNAs) are newly discovered intriguing RNAs due to the covalently closed loop structure, high stability, tissue specificity, and functional diversity. In recent years, a large number of circRNAs have been identified through high-throughput sequencing technology and bioinformatics methods, the abnormal expression of circRNAs are closely related to many diseases including bladder cancer (BC). CircRNAs have been proven to have several functions, such as acting as a regulator of parental gene transcription, miRNA sponge and interacting with proteins to regulate its expression. In addition, some circRNAs have been identified to encode proteins. CircRNAs have the characteristics of high abundance, high stability, wide distribution in body fluids, tissue specificity, and developmental stage specificity, which determine that circRNAs has great potential to be utilized as biomarkers for BC. Herein, we briefly summarize the biogenesis, functions and roles, and the current research progress of circRNAs in BC with a focus on the potential application for BC diagnosis, treatment, and prognosis.

Expression profiles, biological functions and clinical significance of circRNAs in bladder cancer

Circular RNAs (circRNAs), which are single-stranded closed-loop RNA molecules lacking terminal 5′ caps and 3′ poly(A) tails, are attracting increasing scientific attention for their crucial regulatory roles in the occurrence and development of various diseases. With the rapid development of high-throughput sequencing technologies, increasing numbers of differentially expressed circRNAs have been identified in bladder cancer (BCa) via exploration of the expression profiles of BCa and normal tissues and cell lines. CircRNAs are critically involved in BCa biological behaviours, including cell proliferation, tumour growth suppression, cell cycle arrest, apoptosis, invasion, migration, metastasis, angiogenesis, and cisplatin chemoresistance. Most of the studied circRNAs in BCa regulate cancer biological behaviours via miRNA sponging regulatory mechanisms. CircRNAs have been reported to be significantly associated with many clinicopathologic characteristics of BCa, including tumour size, grade, differentiation, and stage; lymph node metastasis; tumour numbers; distant metastasis; invasion; and recurrence. Moreover, circRNA expression levels can be used to predict BCa patients’ survival parameters, such as overall survival (OS), disease-free survival (DFS), and progression-free survival (PFS). The abundance, conservation, stability, specificity and detectability of circRNAs render them potential diagnostic and prognostic biomarkers for BCa. Additionally, circRNAs play crucial regulatory roles upstream of various signalling pathways related to BCa carcinogenesis and progression, reflecting their potential as therapeutic targets for BCa. Herein, we briefly summarize the expression profiles, biological functions and mechanisms of circRNAs and the potential clinical applications of these molecules for BCa diagnosis, prognosis, and targeted therapy.

Identification of a novel circRNA, hsa_circ_0065898, that regulates tumor growth in cervical squamous cell carcinoma

Background

Circular RNAs (circRNAs) were reported to play an important role in regulating tumor pathogenesis. The molecular mechanism of circRNAs in cervical squamous cell carcinoma (CSCC) remains poorly understood. We aimed to identify the circRNAs differentially expressed, and to investigate the role of a novel circRNA, hsa_circ_0065898, in regulating proliferation, migration, and invasion in CSCC.

Methods

The online Kaplan-Meier Plotter was used to analyze the relationship between miRNA expression and overall survival. Bioinformatics tools, such as R, Cytoscape, and Perl, were used to analyze the Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, protein-protein interaction (PPI) network, and regulatory network. The expression level of hsa_circ_0065898 in CSCC cell lines was evaluated using quantitative polymerase chain reaction in vitro. The cell counting kit-8 (CCK-8) and transwell assays were used to assess cell proliferation, migration, and invasion.

Results

circRNA expression data (GSE102686) was downloaded from the Gene Expression Omnibus database, and this included data from 5 CSCC patients and 5 normal tissues. 13 differentially expressed circRNAs were identified, which included 9 upregulated circRNAs and 4 downregulated circRNAs. GO enrichment analysis showed that the target genes of miRNAs associated with hsa_circ_0065898 were enriched in ubiquitin-protein transferase activity, ubiquitin-like protein transferase activity, core promoter sequence-specific DNA binding, mRNA 3’-UTR AU-rich region binding, core promoter binding, and so on. KEGG showed that the Hippo and p53 signaling pathways played significant role in the pathway network. Hsa_circ_0065898 was significantly overexpressed in the CSCC cell lines. Hsa_circ_0065898 facilitated cell proliferation, migration, and invasion in CSCC.

Conclusions

This study identified differentially expressed circRNAs and constructed the regulatory network of hsa_circ_0065898 targeting microRNAs and mRNAs. We demonstrated that hsa_circ_0065898 promoted CSCC cell proliferation, migration, and invasion. Hence, hsa_circ_0065898 might be useful as a biomarker for CSCC diagnosis and targeted therapy.

CircPVT1 Regulates Cell Proliferation, Apoptosis and Glycolysis in Hepatocellular Carcinoma via miR-377/TRIM23 Axis

Background

Recent studies reported that circular RNAs (circRNAs) exert essential functions in hepatocellular carcinoma (HCC) progression. However, the expression profile and function of circular RNA PVT1 (circPVT1) in HCC are not fully addressed. Thus, we aimed to probe into the function of circPVT1 in HCC development.

Methods

The levels of circPVT1, microRNA-377 (miR-377) and transcripts encoding tripartite motif containing 23 (TRIM23) were determined by qRT-PCR. The stability and localization of circPVT1 were examined by RNase R digestion assay and subcellular fraction assay, respectively. Cell proliferation and apoptosis were evaluated by MTT assay and flow cytometry analysis, respectively. The relationship between miR-377 and circPVT1 or TRIM23 was determined by dual-luciferase reporter assay and RNA immunoprecipitation (RIP). The protein expression of TRIM23 was measured by Western blot. The glycolysis level was assessed by specific kits and Seahorse Extracellular Flux Analyzer XF96. The function of circPVT1 in vivo was investigated in a murine xenograft model.

Results

CircPVT1 and TRIM23 levels were elevated, while miR-377 was decreased in HCC. CircPVT1 knockdown restrained proliferation and glycolysis, but enhanced apoptosis in HCC cells. CircPVT1 could bind to miR-377 and inhibition of miR-377 restored circPVT1 knockdown-mediated effect on HCC cells. TRIM23 was certified as a target of miR-377, and TRIM23 upregulation overturned the influence of miR-377 upregulation or circPVT1 silence on HCC progression. Moreover, circPVT1 knockdown restrained tumor growth in HCC in vivo.

Conclusion

CircPVT1 aggravated the progression of HCC by upregulating TRIM23 via sponging miR-377.

circEYA1 Functions as a Sponge of miR-582-3p to Suppress Cervical Adenocarcinoma Tumorigenesis via Upregulating CXCL14

Circular RNAs (circRNAs) function as efficient microRNA (miRNA) sponges that regulate gene expression in the pathogenesis of many human malignancies. However, their roles in cervical adenocarcinoma remain largely unknown. In this study, we aimed to seek novel circRNAs that regulate cervical adenocarcinoma carcinogenesis and to explore their regulatory mechanisms as well as clinical significance. We identified that 24 circRNAs were differentially expressed in cervical adenocarcinoma tissues by RNA sequencing. Among them, circEYA1 was the most significantly downregulated circRNA in cervical adenocarcinoma. In cervical adenocarcinoma cells, circEYA1 overexpression led to suppression of cell viability and colony formation, promotion of apoptosis, and a decrease of the xenograft tumor growth. The mechanism underlying these observations is that circEYA1 functioned as a sponge of miR-582-3p and abrogated its suppression of CXCL14 expression. Consistently, miR-582-3p inhibition phenocopied the biological effects of circEYA1 overexpression in cervical adenocarcinoma cells. Moreover, miR-582-3p overexpression reversed the suppressive behaviors of circEYA1 in vitro and in vivo. In addition, the expression, correlation, and clinical diagnostic value of circEYA1/miR-582-3p/CXCL14 were confirmed in 198 clinical cervical tissue samples. In summary, our findings highlight a novel tumor suppressive role of circEYA1 in cervical adenocarcinoma tumorigenesis and may provide a potential diagnostic marker and therapeutic target for patients with cervical adenocarcinoma.

LINC00265 targets miR-382-5p to regulate SAT1, VAV3 and angiogenesis in osteosarcoma

We explored the mechanism by which LINC00265 regulates angiogenesis of osteosarcoma cells via the miR-382-5p/spermidine/spermine N1-acetyltransferase-1 (SAT1) and miR-382-5p/vav guanine nucleotide exchange factor 3 (VAV3) axis. Cell scratch assay, Transwell assay and tube formation assay were applied to detect cell migration, invasion and tube formation abilities. The effects of LINC00265 targeting miR-382-5p in osteosarcoma in vivo were studied using a tumour-burden assay. A total of 70 genes potentially involved in osteosarcoma angiogenesis were identified, and a Gene Ontology (GO) analysis found that SAT1 and VAV3 were closely related to angiogenesis. Bioinformatics analysis and clinical experiments confirmed that LINC00265, SAT1 and VAV3 were overexpressed in osteosarcoma and related to a poor prognosis, whereas miR-382-5p was downregulated and associated with a poor prognosis. It was confirmed that LINC00265 promoted the proliferation, migration, invasion and angiogenesis of osteosarcoma cells by targeting miR-382-5p to mediate SAT1 and VAV3. Collectively, LINC00265 might promote proliferation, migration, invasion and angiogenesis by targeting miR-382-5p/SAT1 and miR-382-5p/VAV3 in osteosarcoma.