Expression Level Of Hsa Research Articles

Identification of hsa_circ_0005654 as a new early biomarker of gastric cancer.

Gastric cancer is one of the most common cancers in the world. However, current medical technologies have not identified a reliable method to cure advanced gastric cancer, and early gastric cancer is difficult to diagnose. Therefore, we focused on circular RNAs (circRNAs) that have been proven to be involved in the carcinogenesis of gastric cancer. We first used quantitative reverse transcription-polymerase chain reaction (qRT-PCR) to evaluate the expression levels of hsa_circ_0005654 in 301 tissues, including 122 healthy gastric mucosa samples, 68 paired tissues from early gastric cancer and adjacent nontumor mucosae obtained by submucosal dissection, and 43 chronic gastritis tissues. Then, we analyzed the relationship between the expression levels of hsa_circ_0005654 and the clinicopathological characteristics of patients with early gastric cancer. We ultimately confirmed the clinical diagnostic value of hsa_circ_0005654 through generating receiver operating characteristic (ROC) curves and comparing the areas under the ROC curves (AUCs).Our data revealed that hsa_circ_0005654 was significantly downregulated in early gastric cancer tissues compared with matched normal mucosae (P< 0.001). Meanwhile, the expression levels of hsa_circ_0005654 in early gastric cancer tissues were also obviously lower than those in chronic gastritis tissues (P< 0.001). The AUCs of early gastric cancer tissues vs. paired normal adjacent mucosae, and that of early gastric cancer vs. healthy controls, were 0.927 and 0.924, respectively. These results clearly demonstrated that hsa_circ_0005654 may serve as a new and promising diagnostic biomarker for screening early gastric cancer. The AUC, sensitivity and specificity of hsa_circ_0005654 are significantly higher than those of present gastric cancer associated-biomarkers.

Association between circular RNAs expression in serum and gastric cancer

Objective: To analyze the association between circular RNAs expression in serum and gastric cancer and evaluate the potential of the related markers in early diagnosis of gastric cancer. Methods: Forty eight gastric cancer cases in Linqu County People's Hospital were selected as case group, and 48 controls matched by age and sex were randomly selected in the gastric cancer screening cohort during the same period. The expression levels of hsa_circ_002059, hsa_circ_0000096 and hsa_circ_0001895 were detected by quantitative real-time PCR. The results were compared between case group and control group. Results: The positive expression rates of hsa_circ_002059, hsa_circ_0000096 and hsa_circ_0001895 were 70.8%, 47.9%, 75.0% in case group, slightly higher than those in control group (58.3%, 31.3%, 60.4%), although P values were all more than 0.05. The expression level medians of the 3 candidate circRNAs expression levels were 1.60% (0-5.64%), 0 (0-0.61%), 0.91% (0.06%-1.88%) in case group, while 0.05% (0-6.07%), 0 (0-0.34%), 0.42% (0-1.39%) in control group, respectively. Conditional logistic regression analysis showed that the association strength of high expressions of 3 candidate circRNAs with gastric cancer showed an increase trend, but the differences had no significance after adjusted by Helicobacter pylori infection, smoking and drinking status (all P>0.05). Further analysis by combining the 3 candidate circRNAs showed the increased strength of association between circRNAs and gastric cancer with the elevated number of positive circRNAs in serum (trend test P=0.040) compared with circRNAs negative persons. Conclusion: Our study preliminarily suggested that the expression of hsa_circ_002059, hsa_circ_0000096 and hsa_circ_0001895 in serum might be correlated with gastric cancer.

Expression of circular RNA hsa_circ_0014130 in lung adenocarcinoma cell lines and its effect on proliferation and invasion of lung adenocarcinoma cell line

Objective: To investigate the function and mechanism of hsa_circ_0014130 in lung adenocarcinoma cell line and to find potential molecular inhibitors. Methods: The hsa_circ_0014130 expression level detection and overexpression and subtraction experiments were performed using common cell lines of lung cancer (PC9, H1299, A549, HCC827, and BEAS-2B). qPCR was used to verify the proliferation and invasion of lung cancer cells by MTS and invasion assay, and then the targeted microRNA was searched through the database. Western blot was used to detect the downstream signaling pathways, and finally the effect of small molecule inhibitors was investigated on proliferation and invasion of non-small cell lung cancer. Results: The expression level of hsa_circ_0014130 was up-regulated in the three cell lines, and both the overexpression plasmid and the subtractive siRNA were effectively transfected into the cells. Overexpression of hsa_circ_0014130 was able to promote the proliferation and invasion of tumor cells, and knockdown of hsa_circ_0014130 inhibited the proliferation and invasion of tumor cells. hsa_circ_0014130 was capable to target hsa-miR-566 to reduce its expression level and to inhibit epithelial-to-mesenchymal transition. The use of the small molecule inhibitor SB-431542 and simultaneous reduction of hsa_circ_0014130 significantly inhibited the proliferation and invasion of tumor cells. Conclusions: The hsa_circ_0014130 promotes the invasion and proliferation of lung cancer cells by targeting hsa-miR-566 to enhance the expression of TWIST1, and its expression level can be significantly inhibited by the small molecule inhibitor SB-431542, which significantly inhibits the proliferation and invasion of lung cancer cells. Therefore,hsa_circ_0014130 is a potential lung cancer treatment target.

Reduced expression of circRNA hsa_circ_0067582 in human gastric cancer and its potential diagnostic values.

BackgroundGastric cancer (GC) is one of the global mortality diseases and has a poor prognosis due to the lack of ideal tumor biomarkers. Circular RNAs (circRNAs) are an abundant kind of endogenous RNAs that recently are found play a crucial role in the cancer occurrence and development. Nevertheless, little is known with regard to the diagnostic values of these circRNAs for GC. In this article of research, we investigated the role of hsa_circ_0067582 in clinical diagnosis of GC.Materials and MethodsWe used divergent primers, and the expression levels of hsa_circ_0067582 in 93 fresh GC tissues and paired adjacent normal tissues from surgical patients were detected using quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR). Then, a receiver operating characteristic (ROC) curve was established to assess the diagnostic significance of hsa_circ_0067582. The relationship between expression of hsa_circ_0067582 and clinicopathological factors of patients was made further explored.ResultsHsa_circ_0067582 levels were significantly decreased in GC tissues contrasted with adjacent normal tissues (n = 93, P < .001). After that, we discovered that it was evidently downregulated in 81.7% (76/93) GC tissues. The area under the ROC curve (AUC) of hsa_circ_0067582 was up to 0.6937, the sensitivity was 66.67%, and the specificity was 61.29%. Moreover, the hsa_circ_0067582 levels were obviously associated with tumor diameter (P = .002) and carbohydrate antigen 19‐9 (CA19‐9, P = .01). Meanwhile, after operation, low‐level group of hsa_circ_0067582 of GC patients was associated with better prognosis.ConclusionOur data imply that hsa_circ_000067582 may be a potential biomarker for GC diagnosis and prognosis evaluation.

Circular RNA expression profiles following MC-LR treatment in human normal liver cell line (HL7702) cells using high-throughput sequencing analysis

ABSTRACTMicrocystin-LR (MC-LR), a frequently occurring hepatotoxic cyanotoxin produced by cyanobacterial blooms, poses a great threat to human health. However, the precise molecular mechanisms underlying MC-LR-induced hepatotoxicity remain to be determined. Recent investigators found that in many human diseases circular RNAs (circRNAs) a class of endogenous non-coding RNAs played critical roles in disease outcomes. The aim of this study was to investigate whether circRNAs were involved in MC-LR-mediated hepatotoxicity using human normal liver cell line (HL7702). Using high-throughput sequencing analysis data demonstrated that expression levels of 3250, 3111, 3097, 3253 circRNAs were significantly altered at concentrations ranging from 1 to 10 µM MC-LR. Expression levels of hsa_circRNA_0000657 and hsa_circRNA_0000659 were down-regulated while hsa_circRNA_0003247 and hsa_circRNA_0001535 were up-regulated in all MC-LR-exposed groups. The high-throughput sequencing results of selected circRNAs differential expression genes (DEGs) levels were verified by real-time fluorescent quantitative PCR (qRT-PCR). Gene Ontology (GO) enrichment analysis showed that the functions of circRNAs significantly altered in HL7702 cells were predominantly associated with metabolism, systems development, and protein binding. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis data revealed that the target genes of differentially expressed circRNAs in HL7702 cells were involved in FoxO signaling pathway, protein processing in endoplasmic reticulum, Ras signaling pathway, cell cycle, PI3K-Akt signaling pathway, MAPK signaling pathway and pathways in cancer. In summary, evidence indicates that a correlation may exist between circRNAs and MC-LR-induced hepatotoxicity.

Association of circular RNAs and environmental risk factors with coronary heart disease

BackgroundCoronary heart disease (CHD) is a complex disease caused by multi-factors and a major threat to human health. Circular RNAs (circRNAs) have critical roles in various biological processes and diseases. This study explores the independent role of circRNAs and their interaction with environmental factors in CHD.MethodsA case–control study was conducted from March 2015 to September 2017 in Fuzhou, China. A total of 585 CHD patients and 585 gender- and age-matched healthy controls were enrolled. Questionnaire survey, health examination and molecular biology laboratory testing were conducted. Microarray technology and quantitative real-time polymerase chain reaction (PCR) were used to profile the expression levels of circRNAs. The area under the curve (AUC) of the receiver operating characteristic (ROC) was used to determine the diagnostic cut-offs. Multivariate logistic regression and multiplicative analysis were used to analyse the effects of environmental factors and hsa_circ_0008507, hsa_circ_0001946, hsa_circ_0000284 and hsa_circ_0125589 on CHD.ResultsThe expression profile of circRNAs showed that 3423 circRNAs were differentially expressed at P < 0.05, but none pass multiple testing correction. qRT-PCR further confirmed the expression levels of hsa_circ_0008507, hsa_circ_0001946 and hsa_circ_0000284 in peripheral blood leukocytes in CHD cases were higher than those in non-CHD subjects (All p < 0.05). Hsa_circ_0008507 (OR = 1.29; 95% CI: 1.11–1.50), hsa_circ_0001946 (OR = 1.20; 95% CI: 1.01–1.42) and hsa_circ_0000284 (OR = 2.05; 95% CI: 1.32–3.19) were independent risk factors for CHD after controlling other common environmental risk factors. The AUC for hsa_circ_0008507, hsa_circ_0001946 and hsa_circ_0000284 was 0.75, 0.71 and 0.68, respectively. Compared with non-smoking individuals with low hsa_circ_0008507 expression, the smokers with high hsa_circ_0008507 expression showed the highest magnitude of OR in CHD risk. Additionally, a statistically significant multiplicative interaction was found between hsa_circ_0008507 and smoking for CHD.ConclusionsHsa_circ_0008507, hsa_circ_0001946 and hsa_circ_0000284 were closely related to the occurrence and development of CHD. The combination of smoking and high hsa_circ_0008507 expression causes the occurrence and development of CHD.

Effect of circular RNA hsa_circ_0063772 on proliferation, migration and invasion of oral squamous cell carcinoma cells

Objective: To investigate the effects of circular RNA hsa_circ_0063772 on the proliferation, migration and invasion of oral squamous cell carcinoma (OSCC) cells. Methods: Thirty-three patients with oral squamous cell carcinoma who were admitted to the Department of Oral and Maxillofacial Surgery, Peking University Shenzhen Hospital from February 2017 to December 2018 were enrolled in this study. Real-time quantative polymerase chain reaction was used to detect the expression level of circular RNA hsa_circ_0063772 in OSCC and corresponding adjacent tissues, OSCC cell lines and human keratinocytes. The expression level of hsa_circ_0063772 was overexpressed in SCC15 and CAL27 cells by using lentivirus, and the effects of this gene on proliferation, migration and invasion of OSCC cells were detected by cell counting assay, scratch assay, Transwell assay, Western blotting and nude mice tumor formation assay. Results: The expression of circular RNA hsa_circ_0063772 in OSCC tissues (9.38±0.34) was lower than that in adjacent tissues (11.30±0.31) (t=5.20, P<0.001), and the expression in OSCC cells (SCC15: 0.12±0.01; SCC25: 0.18±0.02; SCC9: 0.21±0.01; CAL27: 0.13±0.01) was significantly lower than that in human keratinocytes (1.02±0.02) (t(SCC15)=41.91, t(SCC25)=29.21, t(SCC9)=35.16, t(CAL27)=41.86, P<0.001). Overexpression of hsa_circ_0063772 in SCC15 and CAL27 cells can affect tumor cell proliferation, cell counting assay showed that tumor cell proliferation ability in high expression group (SCC15: 0.76±0.01; CAL27: 0.74±0.02) were lower than empty group (SCC15∶1.22±0.04; CAL27: 0.99±0.03; t(SCC15)=12.58, t(CAL27)=6.97; P<0.05). Transwell migration experiment showed the number of migrated cell in high expression group (SCC15∶148.00±14.57; CAL27: 243.00±13.00) were less than empty group (SCC15: 580.30±42.91; CAL27: 424.70±18.66, P<0.01); Transwell invasion assay showed the number of invased cell in high expression group (SCC15: 123.70±6.98; CAL27: 326.00±17.01) were less than empty group (SCC15: 517.70±9.96; CAL27: 454.30±8.09, P<0.01). The results of tumor formation in nude mice showed that the tumor volume and mass of the overexpressed group [(306.40±16.51) mm(3); (289.40±11.44) mg] were lower than that of the empty group [(582.60±32.51) mm(3), t=7.58, P<0.05; (599.60±21.27) mg, t=7.58, P<0.001]. Conclusions: Compared with adjacent tissues, hsa_circ_0063772 is lowly expressed in oral squamous cell carcinoma. High expression of hsa_circ_0063772 can inhibit the proliferation, migration and invasion of OSCC cells.

CircRNA_0006393 promotes osteogenesis inglucocorticoid‑induced osteoporosis by sponging miR‑145‑5p and upregulating FOXO1.

Glucocorticoids are the most common cause of glucocorticoid‑induced osteoporosis(GIOP). Moreover, the role of circular RNAs (circRNAs) in the regulation of bone metabolism remains unclear. Therefore, in the present study, it was hypothesized that hsa_circ_0006393 may play an important role in GIOP. To investigate the role of circRNAs in GIOP, treatment with dexamethasone or transfection with a vector overexpressing hsa_circ_0006393 were performed using invitro cell and invivo mouse models. Reverse transcription‑quantitative PCR, fluorescence insitu hybridization and western blotting were performed to investigate the function of hsa_circ_0006393 invitro. In addition, the effects of hsa_circ_0006393 on osteogenesis were investigated. Dual‑energy X‑ray absorptiometry analysis was performed to examine the osteogenic potential of hsa_circ_0006393 invivo. Moreover, the mechanism underlying hsa_circ_0006393‑mediated bone metabolism regulation via the microRNA (miR)‑145‑5p/forkhead boxO1 (FOXO1) pathway was investigated. The present results suggested that the expression level of hsa_circ_0006393 was decreased in patients with GIOP. Furthermore, the overexpression of hsa_circ_0006393 increased the expression level of genes associated with osteogenesis. Moreover, hsa_circ_0006393 was identified to be localized mainly in the cytoplasm and nucleus of bone marrow mesenchymal stem cells. miR‑145‑5p was found to be directly targeted by hsa_circ_0006393. Collectively, hsa_circ_0006393 increases the expression levels of osteogenic genes during bone remodeling by sponging miR‑145‑5p and upregulating FOXO1.

Analysis of the circular RNA transcriptome in the grade 3 endometrial cancer.

Background/aimsCircular RNAs (circRNAs), a class of newly discovered endogenous noncoding RNAs, have shown large capabilities in gene regulation. Patients with the grade 3 endometrial cancer (EC) have a generally poor prognosis, and the specific role of circRNAs in the grade 3 EC remains unclear. This study aims to investigate the roles of circRNAs in the grade 3 EC.MethodsIn the current study, we screened the expression profiles of circRNAs taken from two women with the grade 3 EC and adjacent non-cancerous endometrial tissue using circRNAs sequencing. Bioinformatic analyses were applied to study these differentially expressed circRNAs. Quantitative reverse transcription polymerase chain reaction (qRT‐PCR) of six dysregulated circRNAs was performed to validate the sequencing results. Bioinformatic analyses, including the negative correlation network analyses of circRNAs–microRNAs (miRNAs)–messenger RNAs (mRNAs) and the Cytoscape, were used to delineate the interaction of circRNAs/miRNAs of the entire network.ResultsData of circRNA sequencing showed a significant change in 75,928 unique circRNAs (P<0.05). The upregulated hsa_circ_0039569 and hsa_circ_0001610 and downregulated hsa_circ_0000437, hsa_circ_0001776, and hsa_circ_0009043 were validated by qRT-PCR analysis. Using bioinformatical methods, we found that hsa_circ_0039569 has the MRE of hsa-miR-542-3p and hsa-let-7c-5p. Hsa-miR-542-3p and hsa-let-7c-5p were downregulated in the grade 3 EC validated by qRT-PCR analysis. In the clinicopathological parameters, the expression level of hsa_circ_0039569 was significantly correlated with tumor differentiation (P=0.001).ConclusionThis is the first study demonstrated that there were a lot of differences between the tissue of the grade 3 EC and adjacent non-cancerous endometrial in circRNA expression and may offer novel molecular candidates for diagnosis and clinical treatment of the grade 3 EC.

Circular RNA profile of parathyroid neoplasms: analysis of co-expression networks of circular RNAs and mRNAs

ABSTRACTCircular RNAs (circRNAs) are a recently identified class of non-coding RNAs that participate in multiple biological processes and tumour progression. However, circRNA expression pattern in parathyroid neoplasms remains unknown. The circRNA profile of 6 parathyroid carcinomas (PCs), 6 parathyroid adenomas (PAs) and 4 normal parathyroid tissues was assessed by a microarray. Bioinformatic analyses were performed to investigate potential core circRNAs via co-expression network. CircRNA and corresponding mRNA expression were validated in a cohort of parathyroid neoplasms by RT-qPCR and fluorescence in situ hybridization (FISH). Compared to normal parathyroid, 5310 and 1055 circRNAs were differentially expressed in PC and PA tissues, respectively. The differential expression of 4 circRNAs (hsa_circRNA_0035563 (p = 0.006), hsa_circRNA_0017545 (p = 0.009), hsa_circRNA_0001687 (p = 0.005) and hsa_circRNA_0075005 (p = 0.001)) and 4 mRNAs (MYC, FSCN1, ANXA2 and AKR1C3) between PC and PA tissues were confirmed by RT-qPCR. In addition, high expression of hsa_circ_0035563 was related to CDC73 mutations (p = 0.022) and recurrence in PC patients (p = 0.042). Furthermore, hsa_circ_0075005 helped distinguish PCs from benign lesions using FISH, and the area under the curve was 0.779 (p = 0.013). Our findings describe the circRNA profile of PC for the first time and suggest that circRNAs and mRNAs interact in parathyroid tumourigenesis. This study demonstrates that hsa_circ_0075005 and MYC mRNA may be used for the differential diagnosis of PC and PA. The expression levels of hsa_circ_0035563 are related to CDC73 mutations and recurrence in malignancy, highlighting the significance of this parameter in prognosis of PC patients.

Expression profiles of circular RNAs in human colorectal cancer based on RNA deep sequencing.

BackgroundCircular RNAs (circRNAs) are a novel group of RNAs and play essential roles in cancers. However, the expression profiles of circRNAs in human colorectal cancer (CRC) are largely unclear.MethodsThe differentially expressed circRNAs, mRNAs, and microRNAs (miRNAs) between CRC tissues and paired adjacent normal tissues were first screened. Then, gene ontology and pathway analyses were performed to predict the possible functions. In addition, we identified the differentially expressed circRNAs in CRC correlated with Krüppel‐like factor 4 (KLF4) and validated their expression levels in CRC tissues. Finally, the correlations between hsa_circ_0142527 expression levels and clinicopathological features of patients with CRC were also analyzed.ResultsAfter filtered 4735 circRNAs by RNA deep sequencing, 67 differentially expressed circRNAs (fold change >2.0, P < 0.05) were selected. The top two pathways were cell cycle and other glycan degradation. Hsa_circ_0142527 and KLF4 mRNA were significantly lower expressed in CRC tissues in both training and confirm groups and have high positive correlation (r = 0.754). We further found that the expression levels of hsa_circ_0142527 were significantly associated with age (P = 0.004), differentiation (P = 0.008), invasion (P = 0.029), distal metastasis (P = 0.004), TNM stage (P = 0.005), and carcinoembryonic antigen (CEA; P = 0.037).ConclusionsThe circRNA expression profile of CRC provided new clues for understanding the occurrence of CRC. Hsa_circ_0142527 may be served as a potential biomarker for the diagnosis of CRC.

Differences in circRNA expression profiles between HER-2-positive breast cancer cells and normal mammary epithelial cells

Objective: To investigate the differential expression profiles of circular RNA (circRNA) in human epidermal growth factor receptor 2 (HER-2) positive breast cancer cells and normal mammary epithelial cells, and to develop novel diagnostic and therapeutic markers for HER-2 positive breast cancer. Methods: Total RNA were extracted from HER-2 positive breast cancer cell SK-BR-3 and normal mammary epithelial cell MCF10A. RNA quality was detected using NanoDrop ND-1000. Rnase R was applied to remove linear RNA and enrich circRNAs. After amplification and reverse transcription into fluorescent complementary RNA (cRNA) using random primer, the labeled cRNAs were hybridized onto the Arraystar Human circRNA Arrays. The raw data were extracted and the acquired array images were subjected to quantile normalization followed by heat map and volcano plot analysis. The expression of circRNAs with large fold change was verified by real-time quantitative polymerase chain reaction (RT-qPCR). Finally, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed in the differentially expressed circRNAs and circRNA-microRNA (miRNA) network was constructed. Results: The total RNA extracted from SK-BR-3 and MCF10A had high integrity and quality. The expression profiles of circRNA in SK-BR-3 and MCF10A cells were significantly different shown by fluorescent expression signals. Compared with MCF10A cells, there were 6 584 up-regulated circRNAs and 6254 down-regulated circRNAs in SK-BR-3 cells. There were 348 circRNAs with |log(2)FC|≥2, of which 153 were up-regulated and 195 were down-regulated. Moreover, 8 circRNAs with |log(2)FC|>5. Among them, 5 were up-regulated in SK-BR-3 cells, including hsa_circRNA_074595 (|log(2)FC|=7.84), hsa_circRNA_074598 (|log(2)FC|=6.50), hsa_circRNA_085362 (|log(2)FC|=5.86), hsa_circRNA_101379 (|log(2)FC|=5.71) and hsa_circRNA_406683 (|log(2)FC|=5.34); as well as 3 were down-regulated, including hsa_circRNA_021714 (|log(2)FC|=5.46), hsa_circRNA_100777 (|log(2)FC|=5.40), and hsa_circRNA_100796 (|log(2)FC|=5.03). The expression levels of hsa_circRNA_074595, hsa_circRNA_074598 and hsa_circRNA_100777 were further validated by RT-qPCR in consistent with the results of microarray. GO analysis showed that differentially expressed circRNAs were significantly enriched in the biological process of heart development (P<0.001), cellular component in the cell adhesion-related components (P<0.001), molecular function in protein serine/threonine kinase activity (P<0.001). KEGG analysis revealed that differentially expressed circRNAs were significantly enriched in the PI3K-Akt signaling pathway. Conclusions: The expression profile of circRNA in HER-2 positive breast cancer cells is significantly different from that in normal mammary epithelial cells. The differentially expressed circRNAs may be served as potential diagnostic or therapeutic targets for HER-2 positive breast cancer.

Microarray Profiling of Circular RNA Identifies hsa_circ_0126991 as a Potential Risk Factor for Essential Hypertension

Essential hypertension (EH), a major cause of cardiovascular diseases, is an important public health issue. However, the molecular mechanisms involved in EH remain unknown. Circular RNA (circRNA) is a novel promising biomarker for the disease. The purpose of the present study was to determine the expression of circRNAs in the blood of EH patients and to evaluate the performance of circRNA for early diagnosis of EH. A total of 178 subjects were recruited in the case-control study. Initial screening was done by using the Agilent human circRNA microarray followed by qRT-PCR validation. Finally, miRNAs were combined with circRNAs to create a new early prediction model for EH. The expression level of hsa_circ_0126991 in EH patients was significantly higher in comparison with healthy controls (p < 0.0001). Using the interaction of miR-10a-5p in combination with hsa_circ_0126991 led to a sensitivity of 0.708, a specificity of 0.764, and combined area under the curve of 0.774 (95% CI: 0.705-0.843) for early diagnosis of EH. In summary, the present study uncovered a novel perspective that hyperexpression of hsa_circ_0126991 is correlated with the risk of EH and may serve as a stable biomarker for early diagnosis of EH.

Circular RNA hsa_circ_009755 downregulation correlates with clinicopathology in oral squamous cell carcinoma.

Background: Oral squamous cell carcinoma (OSCC) is the most frequent oral malignancy in humans. Increasing numbers of studies suggest that circular RNAs (circRNAs) play a major role in tumorigenesis and tumor progression.Purpose: We aimed to identify differently expressed circRNA in OSCC and adjacent normal tissue. As well as to study the correlation of circRNA expression with clinicopathological feature in patients with OSCC.Patients and methods: Primary OSCC tissues and adjacent normal tissues from twenty-seven OSCC patients were collected. The expression level of hsa_circ_009755 were analyzed by qRT-PCR.Results: The measurement results from qRT-PCR revealed that hsa_circ_009755 expression was low in OSCC tissue samples and cell lines, and the low expression of hsa_circ_009755 was closely related to a clinicopathological feature in patients with OSCC. Moreover, the area under the receiver operating characteristic curve was 0.782, which indicates the sensitivity and specificity of the diagnostic value.Conclusion: Our data indicates that hsa_circ_009755 could serve as a potential biomarker for OSCC diagnosis.

Circular RNA hsa_circ_0068871 regulates FGFR3 expression and activates STAT3 by targeting miR-181a-5p to promote bladder cancer progression

BackgroundFGFR3 plays an important role in the development of bladder cancer (BCa). Hsa_circ_0068871 is a circRNA generated from several exons of FGFR3. However, the potential functional role of hsa_circ_0068871 in BCa remains largely unknown. Here we aim to evaluate the role of hsa_circ_0068871 in BCa.MethodsWe selected miR-181a-5p as the potential target miRNA of hsa_circ_0068871. The expression levels of hsa_circ_0068871 and miR-181a-5p were examined in BCa tissues and paired adjacent normal tissues by quantitative real-time PCR. To characterize the function of hsa_circ_0068871, BCa cell lines were stably infected with lentivirus targeting hsa_circ_0068871, followed by examinations of cell proliferation, migration and apoptosis. In addition, xenografts experiment in nude mice were performed to evaluate the effect of hsa_circ_0068871 in BCa. Biotinylated RNA probe pull-down assay, fluorescence in situ hybridization and luciferase reporter assay were conducted to confirm the relationship between hsa_circ_0068871, miR-181a-5p and FGFR3.ResultsHsa_circ_0068871 is over-expressed in BCa tissues and cell lines, whereas miR-181a-5p expression is repressed. Depletion of has_circ_0068871 or upregulation of miR-181a-5p inhibited the proliferation and migration of BCa cells in vitro and in vivo. Mechanistically, hsa_circ_0068871 upregulated FGFR3 expression and activated STAT3 by targeting miR-181a-5p to promote BCa progression.ConclusionsHsa_circ_0068871 regulates the miR-181a-5p/FGFR3 axis and activates STAT3 to promote BCa progression, and it may serve as a potential biomarker.

Novel circular RNA expression in the cumulus cells of patients with polycystic ovary syndrome.

Circular RNAs (circRNAs) mediate the posttranscriptional regulation of multiple genes by functioning as microRNA (miRNA) sponges. This study aimed to detect the novel expression of circRNAs in the cumulus cells (CCs) of polycystic ovary syndrome (PCOS) patients and their potential significance in the pathogenesis of PCOS. circRNAs in the CCs from 6 PCOS patients and 6 normal control individuals were collected for microarray analysis, and an independent cohort study including 25 PCOS patients and 25 normal control individuals was conducted to validate the circRNA microarray results using quantitative real-time polymerase chain reaction (qRT-PCR). Spearman's rank correlation and receiver operating characteristic (ROC) were performed to delineate the potential correlation between novel circRNAs and patients' clinical characteristics and their potential efficacy for the diagnosis of PCOS. Bioinformatics analysis was applied to investigate the potential roles of circRNAs in the pathogenesis of PCOS. A total of 286 circRNAs (167 upregulated and 119 downregulated) were identified by microarray that was differentially expressed between the PCOS and non-PCOS groups. After qRT-PCR validation, the expression levels of hsa_circ_0043533 (p < 0.05) and hsa_circ_0043532 (p < 0.01) were significantly higher in the PCOS group, while the expression level of hsa_circ_0097636 (p < 0.01) was prominently lower versus the non-PCOS group. Spearman's rank correlation indicated that the serum testosterone (T) level positively correlated with the expression of hsa_circ_0043533 and hsa_circ_0097636 in the PCOS group. The ROC curve analysis found that the combination of hsa_circ_0097636 and T resulted in a larger area under the curve (AUC) (0.893) compared with each circRNA alone (0.709, 0.738, and 0.718 for hsa_circ_0043533, hsa_circ_0097636 and hsa_circ_0043532, respectively). Bioinformatics analysis revealed that the dysregulated circRNAs were potentially involved in cell cycle, oocyte meiosis, progesterone-mediated oocyte maturation, the FOXO signaling pathway, phosphatidylinositol signaling and glycerophospholipid metabolism. The expression of circRNAs in CCs was significantly different between PCOS and normal control individuals. We validated three circRNAs, which could lead to a better understanding of disease pathogenesis and the development of effective therapeutic interventions for PCOS patients.

Up-regulated circular RNA hsa_circ_0067934 contributes to glioblastoma progression through activating PI3K-AKT pathway.

Circular RNAs (circRNAs) are involved in cancer progression and metastasis, although little is known about their role in glioblastoma (GBM). The aim of this study was to investigate the expression pattern and molecular mechanism of hsa_circ_0067934 in GBM. Hsa_circ_0067934 expression was detected in GBM tissues and cell lines by using RT-PCR. The prognostic value of the hsa_circ_0067934 expression in GBM patients was statistically analyzed. The effects of hsa_circ_0067934 expression on growth and apoptosis of GBM cells were analyzed by CCK-8, colony formation, and flow cytometry. Migration and invasion ability was evaluated by transwell and wound-healing assays. The protein expression of signaling pathways was determined by using Western blot. The expression level of hsa_circ_0067934 was significantly increased in GBM tissues and cancer cells. Kaplan-Meier survival curves showed that patients with higher expression of hsa_circ_0067934 had a more favorable overall survival and disease-free survival. The functional investigations revealed that the knockdown of hsa_circ_0067934 suppressed GBM cell proliferation, metastasis and EMT, and promoted apoptosis. Moreover, the mechanistic analysis demonstrated that the down-regulation of hsa_circ_0067934 significantly suppressed the activation of the PI3K-AKT pathway. Hsa_circ_0067934 is overexpressed and plays an oncogenic role in GBM by promoting cancer cell proliferation and metastasis via upregulation of PI3K-AKT pathway, which suggests that hsa_circ_0067934 is likely to serve as an efficient therapeutic approach in respect of GBM treatment.

CircRNA hsa_circRNA_101996 increases cervical cancer proliferation and invasion through activating TPX2 expression by restraining miR-8075.

In recent years, circular RNAs have been shown to serve as essential regulators in several human cancers. Nevertheless, the function and mechanism of CircRNA in cervical cancer remain elusive. In the present study, we showed that hsa_circRNA_101996 was highly expressed in cervical cancer tissues compared with matched normal tissues by bioinformatics analysis. We showed that the expression level of hsa_circRNA_101996 in cervical cancer tissues was positively correlated with TNM stage, tumor size, and lymph node metastasis. Moreover, higher levels of hsa_circRNA_101996 were related to poor outcomes of cervical cancer patients. We found that knockdown of hsa_circRNA_101996 significantly inhibited the proliferation, cell cycle, migration, and invasion of cervical cancer cells. Mechanistically, we demonstrated that hsa_circRNA_101996 served as a sponge of miR-8075, which targeted TPX2 in cervical cancer cells. We showed that miR-8075 that was downregulated in cervical cancer tissues repressed cervical cancer cell proliferation, migration, and invasion. Furthermore, we validated that upregulation of TPX2 by hsa_circRNA_101996-mediated inhibition of miR-8075 contributed to cervical cancer proliferation, migration, and invasion. Taken together, our findings revealed a novel mechanism that hsa_circRNA_101996-miR-8075-TPX2 network promoted cervical cancer progression.

Differential circRNA expression profiles in latent human cytomegalovirus infection and validation using clinical samples.

Human cytomegalovirus (HCMV) is an opportunistic prototypic beta-herpesvirus that can cause severe and even fatal diseases in immune-naive newborns and immunocompromised adults. Host-virus interactions occurring at the transcriptional and posttranscriptional levels are critical for establishing an HCMV latent or lytic infection, but the mechanisms remain poorly understood. Herein, we investigated the expression of circRNAs in human leukemia monocytes (THP-1 cells) latently infected with HCMV and explored the diagnostic value of circRNAs in children with HCMV infection. A total of 2,110 and 1,912 circRNAs were identified in mock-infected and HCMV latent-infected THP-1 cells, respectively. Of these, we identified 1,421 differently expressed circRNAs, of which 650 were upregulated and 771 were downregulated. The host genes corresponding to the differentially expressed circRNAs were mainly involved in the regulation of host cell secretion pathways, cell cycle, and cell apoptosis. The differentially expressed circRNAs had binding sites for microRNAs, suggesting an important role in the mechanism of HCMV latent infection. Furthermore, a clinical analysis showed that the expression levels of hsa_circ_0001445 and hsa_circ_0001206 were statistically significantly different in HCMV-infected patients vs. normal controls, suggesting that these circRNAs could potentially serve as biomarkers of HCMV-infection.

Hsa_circ_0000467 promotes cancer progression and serves as a diagnostic and prognostic biomarker for gastric cancer.

Emerging evidence indicates that dysregulation of circular RNAs (circRNAs) is implicated in the development of malignancies. However, the diagnostic value and functional role of circRNAs in gastric cancer (GC) remain largely elusive. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was performed to detect the expression of hsa_circ_0000467 in tissues, cell lines, and plasma. A receiver operating characteristic (ROC) curve was constructed to estimate the diagnostic value of hsa_circ_0000467. The association between the expression level of hsa_circ_0000467 and the clinicopathological features was analyzed. Moreover, cell functional assays were performed. Hsa_circ_0000467 was significantly upregulated in GC tissue compared to adjacent nontumor tissue (n=51, P<0.05). Similar results were detected in the HGC-27, MGC-803, AGS, NUGC-3, GES-1 cell lines (n=15, P<0.001), and in the plasma samples from GC patients (n=20, P<0.05). The area under the ROC curve of hsa_circ_0000467 was 0.790, which is superior to commonly used biomarkers including CEA and CA-724. We found that the expression levels of hsa_circ_0000467 in the same patient were significantly lower after surgery (n=20, P<0.05). Moreover, the hsa_circ_0000467 expression level is closely associated with TNM stage. Additionally, Cox multivariate analysis showed that hsa_circ_0000467 is a novel independent prognostic factor. Furthermore, in vitro experiments demonstrated that knockdown of hsa_circ_0000467 markedly inhibited the proliferation, migration, and invasion of GC cells. Moreover, hsa_circ_0000467 silencing increased tumor apoptosis in vitro. Hsa_circ_0000467 can act as a novel noninvasive biomarker for the diagnosis and prognosis of GC and may be a potential therapeutic target for GC.