Circular RNA expression profiling identifies hsa_circ_0011460 as a novel molecule in severe preeclampsia.

To identify circRNA expression profiles in the placentae of severe preeclampsia (SPE) and normal pregnant (NP) women. Placental samples were collected from six paired SPE and NP women. CircRNA expression profiles were identified by RNA-Seq and validated in another 30 SPE and NP samples by qRT-PCR. Several bioinformatic tools were utilised to analyse the potential function of differentially expressed circRNAs (DE-circRNAs) and to predict target microRNAs (miRNAs) and proteins. Furthermore, immunohistochemistry, Western blotting and RNA binding protein immunoprecipitation (RIP) were conducted to confirm the interaction between the circRNA and protein. In total, 18,631 circRNAs were detected. Among them, 180 circRNAs were differentially expressed, including 94 upregulated and 86 downregulated circRNAs. Seven DE-circRNAs were selected for validation, and the results of six circRNAs (hsa_circ_0007611, hsa_circ_0011460, hsa_circ_0002888, and hsa_circ_0007445, hsa_circ_0017068, hsa_circ_0012737) were consistent with the sequencing results. Bioinformatics analyses of DE-circRNAs revealed that most of them are involved in vasodilation, regulation of blood vessel size, protein transport and localization, and pathways in cancer. In addition to the mRNA expression profile, it was interesting to find that the hsa_circ_0011460 target gene solute carrier organic anion transporter family member 2A1 (SLCO2A1, PGT) was also significantly increased in SPE placentae. Immunohistochemistry, Western blotting and qRT-PCR validated the expression and distribution of PGT. Finally, RIP of HTR-8/SVneo cells confirmed that hsa_circ_0011460 targets PGT directly. A total of 180 DE-circRNAs were detected. One crucial circRNA, hsa_circ_0011460, was shown to interact directly with its host gene PGT. These findings indicated that hsa_circ_0011460 may serve as a potential therapeutic target for patients with SPE.

Deng N ，Lei D ，Huang J ，Yang Z ，Fan C ，Wang S ... -  《-》

The expression profile of circRNA and its potential regulatory targets in the placentas of severe pre-eclampsia.

To determine the expression profiles of circular RNAs (circRNAs) of women with severe pre-eclampsia (sPE group) versus normal pregnancies (normal control group). RNA-sequencing (RNA-seq) was conducted to characterize differentially expressed circRNAs and mRNAs in the placental tissues of women with sPE versus normal pregnancies. circRNA functions were predicted by Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) database analysis. The backsplicing junctions of circRNAs were validated with the use of divergent primers. Relative expression levels of cirRNAs were verified by quantitative real-time PCR (qPCR). A circRNA-miRNA-mRNA interaction network was constructed to outline the regulatory network of the differentially expressed circRNAs. A total of 49 differentially expressed circRNAs were found in the placental tissues of women with sPE. Several differentially expressed mRNAs were also observed in the sPE patients. KEGG analysis revealed that the most enriched pathway of the circRNAs was the MAPK signaling pathway, while the differentially expressed mRNAs were primary enriched in pathways in cancer. Among these circRNAs, hsa_circ_0001438, hsa_circ_0001326, and hsa_circ_32340 were upregulated in the sPE patients and the circRNA-miRNA-mRNA interaction network generated with these three circRNAs revealed a broad regulatory network that might be involved in the pathogenesis of sPE. circRNAs are differentially expressed in sPE. The upregulation of hsa_circ_0001438, hsa_circ_0001326, and hsa_circ_32340 has a potential role in the regulation of miRNA and mRNA expression. Changes to the expression profiles of the circRNAs might be linked to the pathogenesis of sPE and could function as biomarkers.

Ou Y ，Liu M ，Zhu L ，Deng K ，Chen M ，Chen H ，Zhang J ... -  《-》

CircRNA-0004904, CircRNA-0001855, and PAPP-A: Potential Novel Biomarkers for the Prediction of Preeclampsia.

Circular RNAs (circRNAs) are transcribed prevalently in the genome; however, their potential roles in multiple cardiovascular diseases, particularly preeclampsia (PE), are not yet well understood. This study investigated the expression profiles of circRNAs and explored circRNA-mediated pregnancy-associated plasma protein A (PAPP-A) expression as a potential biomarker for PE before 20 weeks of pregnancy. A nested case-control two-phase screening/validation study was performed in pregnant women before 20 weeks of gestation (before clinical diagnosis) at Guangzhou Women and Children's Medical Center from 2012 to 2015. In the screening phase, circRNA expression profiles of blood cells were assessed using a human circRNA microarray, which was designed to detect simultaneously 5396 circRNAs, in 5 patients with PE and 5 age- and gestational week-matched controls. In the validation phase, 18 circRNAs in blood cells predicted by bioinformatics tools were validated by quantitative reverse transcription PCR in a cohort of 60 patients (PE and age-, gestational week-, and sample storage time-matched controls). Then, we examined the involvement of circRNAs in PE-related pathways via interactions with miRNAs by multiple bioinformatics approaches. Bioinformatics analysis predicted that hsa_circ_0004904 and hsa_circ_0001855 miRNA sponges directly target PAPP-A. PAPP-A was verified in the serum of the same cohort of patients using an enzyme-linked immunosorbent assay. Finally, we combined PAPP-A with circRNAs to create a novel preclinical diagnostic model for PE with logistic regression and evaluated the efficiency of this model with receiver operating curve analysis. Volcano plot analysis using various parameters showed that circRNAs were differentially expressed among both groups (P < 0.01, fold change > 2). In the screening phase, we found that 2178 circRNAs were differentially expressed between the control and PE groups, in which 884 circRNAs were downregulated and 1294 circRNAs were upregulated in the PE group compared with the control group. In the validation phase, two circRNAs, hsa_circ_0004904 and hsa_circ_0001855, were significantly upregulated in PE patients compared with healthy pregnant women (P < 0.05). PAPP-A expression levels, related to the two circRNAs based on bioinformatics prediction, were increased in the PE group compared with the control group. The area under the curve of the combined model was 0.94 in the predicted PE subjects. This is the first study to report circRNA profiling in patients with PE prior to the onset of symptoms. Our data suggested that hsa_circ_0004904 and hsa_circ_0001855 combined with PAPP-A might be promising biomarkers for the detection of PE. Moreover, circRNAs may provide new insights into the potential mechanisms underlying the pathophysiology of PE.

Jiang M ，Lash GE ，Zhao X ，Long Y ，Guo C ，Yang H ... -  《-》

Competing endogenous RNA expression profiling in pre-eclampsia identifies hsa_circ_0036877 as a potential novel blood biomarker for early pre-eclampsia.

Hu X ，Ao J ，Li X ，Zhang H ，Wu J ，Cheng W ... -  《-》

A comprehensive evaluation of skin aging-related circular RNA expression profiles.

Circular RNAs (circRNAs) have been shown to play important regulatory roles in a range of both pathological and physiological contexts, but their functions in the context of skin aging remain to be clarified. In the present study, we therefore, profiled circRNA expression profiles in four pairs of aged and non-aged skin samples to identify identifying differentially expressed circRNAs that may offer clinical value as biomarkers of the skin aging process. We utilized an RNA-seq to profile the levels of circRNAs in eyelid tissue samples, with qRT-PCR being used to confirm these RNA-seq results, and with bioinformatics approaches being used to predict downstream target miRNAs for differentially expressed circRNAs. In total, we identified 571 circRNAs with 348 and 223 circRNAs being up and downregulated that were differentially expressed in aged skin samples compared to young skin samples. The top 10 upregulated circRNAs in aged skin sample were hsa_circ_0123543, hsa_circ_0057742, hsa_circ_0088179, hsa_circ_0132428, hsa_circ_0094423, hsa_circ_0008166, hsa_circ_0138184, hsa_circ_0135743, hsa_circ_0114119, and hsa_circ_0131421. The top 10 reduced circRNAs were hsa_circ_0101479, hsa_circ_0003650, hsa_circ_0004249, hsa_circ_0030345, hsa_circ_0047367, hsa_circ_0055629, hsa_circ_0062955, hsa_circ_0005305, hsa_circ_0001627, and hsa_circ_0008531. Functional enrichment analyses revealed the potential functionality of these differentially expressed circRNAs. The top 3 enriched gene ontology (GO) terms of the host genes of differentially expressed circRNAs are regulation of GTPase activity, positive regulation of GTPase activity and autophagy. The top 3 enriched KEGG pathway ID are Lysine degradation, Fatty acid degradation and Inositol phosphate metabolism. The top 3 enriched reactome pathway ID are RAB GEFs exchange GTP for GDP on RABs, Regulation of TP53 Degradation and Regulation of TP53 Expression and Degradation. Six circRNAs were selected for qRT-PCR verification, of which 5 verification results were consistent with the sequencing results. Moreover, targeted miRNAs, such as hsa-miR-588, hsa-miR-612, hsa-miR-4487, hsa-miR-149-5p, hsa-miR-494-5p were predicted for circRna-miRna interaction networks. Overall, these results offer new insights into circRNA expression profiles, potentially highlighting future avenues for research regarding the roles of these circRNAs in the context of skin aging.

Wang L ，Si X ，Chen S ，Wang X ，Yang D ，Yang H ，He C ... -  《-》