The study on circRNA profiling uncovers the regulatory function of the hsa_circ_0059665/miR-602 pathway in breast cancer.
Abnormal expression of circRNAs has been observed in different types of carcinomas, and they play significant roles in the biology of these cancers. Nevertheless, the clinical relevance and functional mechanisms of the majority of circRNAs implicated in breast cancer progression remain unclear. The primary objective of our investigation is to uncover new circRNAs in breast cancer and elucidate the underlying mechanisms by which they exert their effects. The circRNA expression profile data for breast cancer and RNA-sequencing data were acquired from distinct public databases. Differentially expressed circRNAs and mRNA were identified through fold change filtering. The establishment of the competing endogenous RNAs (ceRNAs) network relied on the interplay between circular RNAs, miRNAs, and mRNAs. The hub genes were identified from the protein-protein interaction (PPI) regulatory network using the CytoHubba plugin in Cytoscape. Moreover, the expression levels and prognostic value of these hub genes in the PPI network were assessed using the GEPIA and Kaplan-Meier plotter databases. Fluorescence in situ hybridization (FISH) was used to identified the expression and intracellular localization of hsa_circ_0059665 by using the tissue microarray. Transwell analysis and CCK-8 analysis were performed to assess the invasion, migration, and proliferation abilities of breast cancer cells. Additionally, we investigated the interactions between hsa_circ_0059665 and miR-602 through various methods, including FISH, RNA-binding protein immunoprecipitation (RIP), and luciferase reporter assay. Rescue experiments were conducted to determine the potential regulatory role of hsa_circ_0059665 in breast cancer progression. A total of 252 differentially expressed circRNAs were identified. Among them, 246 circRNAs were up-regulated, while 6 circRNAs were down-regulated. Based on prediction and screening of circRNA-miRNA and miRNA-mRNA binding sites, we constructed a network consisting of circRNA-miRNA-mRNA interactions. In addition, we constructed a Protein-Protein Interaction (PPI) network and identified six hub genes. Moreover, the expression levels of these six hub genes in breast cancer tissues were found to be significantly lower. Furthermore, the survival analysis results revealed a significant correlation between low expression levels of KIT, FGF2, NTRK2, CAV1, LEP and poorer prognosis in breast cancer patients. The FISH experiment results indicated that hsa_circ_0059665 exhibits significant downregulation in breast cancer, and its decreased expression is linked to poor prognosis in breast cancer patients. Functional in vitro experiments revealed that overexpression of hsa_circ_0059665 can inhibit proliferation, migration and invasion abilities of breast cancer cells. Further molecular mechanism studies showed that hsa_circ_0059665 exerts its anticancer gene role by acting as a molecular sponge for miR-602. In our study, we constructed and analyzed a circRNA-related ceRNA regulatory network and found that hsa_circ_0059665 can act as a sponge for miR-602 and inhibit the proliferation, invasion and migration of breast cancer cells.
Wu Z
,Wu M
,Jiang X
,Shang F
,Li S
,Mi Y
,Geng C
,Tian Y
,Li Z
,Zhao Z
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《Scientific Reports》
Identification of the hsa_circ_0039466/miR-96-5p/FOXO1 regulatory network in hepatocellular carcinoma by whole-transcriptome analysis.
Circular RNAs (circRNAs) are important for the process of cancer initiation and progression. However, the role of circRNAs in hepatocellular carcinoma (HCC) remains incompletely understood. Therefore, we further explored the expression network of circRNAs in HCC.
Whole-transcriptome microarrays of HCC and paired normal liver tissues were obtained from the Gene Expression Omnibus (GEO) database. The structures of tumor-associated circRNAs were acquired by the Cancer-Specific CircRNA Database (CSCD). StarBase, circBank, and R packages (miRNAtap and multiMiR) were used to predict miRNA targets of circRNAs and downstream molecules of miRNAs. Expression relationships between RNA-RNA interactions were evaluated by data from The Cancer Genome Atlas (TCGA) and GEO databases. ClusterProfiler and DOSE R packages were used for pathway enrichment to explore the biological functions of potential target genes. Finally, a possible circRNA-miRNA-mRNA regulatory network was established based on the competing endogenous RNA (ceRNA) hypothesis.
The differentially expressed circRNAs (DECs) were matched with cancer-specific circRNAs in the CSCD database and a screening analysis was performed to obtain 5 cancer-specific circRNAs. A total of 329 possible target miRNAs for 5 cancer-specific circRNAs were predicted by the circBank database, and intersection analysis with differentially expressed miRNAs (DEmiRNAs) revealed that miR-6746-3p and miR-96-5p were the two most suitable miRNAs targets for our selected circRNAs. Further expression verification and prediction of base complementary paired binding sites demonstrated the hsa_circ_0039466/miR-96-5p axis as a crucial pathway in HCC. Next, we found that FOXO1 and LEPR were two potential downstream molecules of the hsa_circ_0039466/miR-96-5p axis through target gene prediction analysis, differential expression analysis, and intersection analysis. The pathway enrichment results suggested that the hsa_circ_0039466/miR-96-5p axis affects the progression and outcome of HCC through the insulin resistance pathway. Finally, through multi-data crossover analysis and data analysis of HCC samples further confirmed the existence of the hsa_circ_0039466/miR-96-5p/FOXO1 ceRNA regulatory network and that the axis was closely related to clinical stage.
hsa_circ_0039466 facilitates the expression of FOXO1 by sponging miR-96-5p, and ultimately inhibits tumor progression. These results provide a theoretical basis for further understanding of the gene expression network of HCC.
Yuan F
,Tang Y
,Cao M
,Ren Y
,Li Y
,Yang G
,Ou Q
,Tustumi F
,Levi Sandri GB
,Raissi D
,Pocha C
,Deng M
,Yao Z
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Identification of a circRNA/miRNA/mRNA ceRNA Network as a Cell Cycle-Related Regulator for Chronic Sinusitis with Nasal Polyps.
To explore the mechanisms by which circRNA/miRNA/mRNA competitive endogenous RNAs (ceRNA) networks regulate CRSwNP.
The expression profiles of circRNAs, miRNAs, and mRNAs from patients with CRSwNP and control subjects were acquired from the Gene Expression Omnibus database. The circRNA/miRNA/mRNA ceRNA network was constructed based on the predicted circRNA-miRNA interactions and miRNA-mRNA interactions. Hub-mRNAs were screened by protein-protein interaction network analysis and Cytoscape molecular complex detection. The expression of factors in tissue and in hsa_circ_0031594 siRNA transfection cells was verified by RT-qPCR and the association between them was revealed by Spearman correlation analysis. Receiver operating characteristic curve analysis was performed with the pROC R package.
The differential expression of 5423 circRNAs, 415 miRNAs, and 3673 mRNAs was identified in CRSwNP subjects compared to control subjects. Among these, 9 circRNAs, 39 miRNAs, and 78 mRNAs were screened to construct a ceRNA network. Ultimately, a subnetwork including circRNA hsa_circ_0031594, hsa-miR-1260b, hsa-miR-6507-5p, NCAPG2, RACGAP1, CHEK1 and PRC1 was screened out. RT-qPCR validated that the expression of hsa_circ_0031594, NCAPG2, PRC1 was significantly increased, and hsa-miR-1260b and hsa-miR-6507-5p were expressed significantly less in patients with CRSwNP than in control subjects. In addition, the AUCs of hsa_circ_0031594, hsa-miR-1260b, hsa-miR-6507-5p, NCAPG2, and PRC1 to discriminate CRSwNP patients were 0.995, 0.842, 0.862, 0.765, and 0.816. Spearman correlation showed that the expression of hsa_circ_0031594 was negatively correlated with hsa-miR-1260b and hsa-miR-6507-5p, and positively correlated with NCAPG2 and PRC1. In human nasal epithelial cell (HNEpC) line, knocking down hsa_circ_0031594 could increase the expression of hsa-miR-1260b and hsa-miR-6507-5p, and reduce the expression of NCAPG2 and PRC1.
CeRNA networks including hsa_circ_0031594, hsa-miR-1260b, and NCAPG2, and hsa_circ_0031594, hsa-miR-6507-5p, and PRC1 may be key regulators for CRSwNP occurrence, and may be potential targets for the pathogenesis and treatment development of CRSwNP.
Sun Q
,Liu Z
,Xu X
,Yang Y
,Han X
,Wang C
,Song F
,Mou Y
,Li Y
,Song X
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《Journal of Inflammation Research》