CircSLC8A1_005 Inhibits the Fibrotic Phenotype of Cardiac Fibroblasts by Encoding Protein / 中山大学学报(医学科学版)

ObjectiveTo investigate the effect of circSLC8A1_005 on the fibrotic phenotype of cardiac fibroblasts and the potential mechanism involved. MethodsThe effect of adenovirus-mediated overexpression of circSLC8A1_005 on the expression of fibrosis-related genes， collagen type I alpha 1 chain （Col1a1）， collagen type Ⅲ alpha 1 chain （Col3a1） and smooth muscle actin alpha 2 （Acta2）， in mouse cardiac fibroblasts （mCFs） were detected. The proliferation and migration activities of mCFs were detected by EdU and wound-healing assay， respectively. Dual luciferase reporter gene assay was performed to detect the activity of potential internal ribozyme entry site （IRES） in circSLC8A1_005. CircSLC8A1_005-translated protein， SLC8A1-605aa， and its intracellular distribution was identified by Western blot assay. The effect of SLC8A1-605aa protein on transcription activity of Sod2 gene was detected by the dual luciferase reporter gene assay. RNA binding protein immunoprecipitation （RIP） was utilized to verify the interaction between SLC8A1-605aa and superoxide dismutase 2 （Sod2） mRNA. Actinomycin D treatment was used to detect the effect of SLC8A1-605aa on Sod2 mRNA stability in mCFs. ResultsAn efficient adenovirus-mediated overexpression of circSLC8A1_005 was achieved in mCFs. The enforced expression of circSLC8A1_005 suppressed proliferation and migration of mCFs， and inhibited the expression of fibrosis-related genes in mCFs. The dual luciferase reporter gene assay revealed the activities of 2 IRES in circSLC8A1_005. Results of Western blot assay showed that circSLC8A1_005 could translate protein SLC8A1-605aa with the prospected molecular weight of 70 ku， which is predominantly distributed in the nucleus. Overexpression of the circSLC8A1_005 and SLC8A1-605aa could consistently inhibit the fibrotic phenotype of mCFs. SLC8A1-605aa could up-regulate superoxide dismutase 2 （Sod2） expression， but not at the transcriptional level. RIP assay indicated that SLC8A1-605aa could specifically interact with Sod2 mRNA， and the results of actinomycin D assay showed that SLC8A1-605aa could enhance the stability of Sod2 mRNA in mCFs. ConclusionCircSLC8A1_005 inhibits the fibrotic phenotype of cardiac fibroblasts via translating SLC8A1-605aa protein， and SLC8A1-605aa may be a potential target for the treatment of myocardial fibrosis.

Construction and expression of circular RNA in vitro / 中国生物制品学杂志

@#Objective To construct encoding RNA that can be cyclized in vitro by using the permuted intron exon(PIE)strategy in the maturation process of eukaryotic mRNA,and transfect it into HEK-293T cells for expression.Methods The sequences of 5'and 3'cyclic arms with groupⅠcatalytic intron,the internal ribosome entry sites(IRES)of Coxsackievirus B3(CVB3)and the target gene were selected to construct the template plasmid. Linearization plasmid template obtained by PCR was used to synthesize linear RNA through in vitro transcription(IVT),which then started in vitro cyclization(IVC)by the addition of cyclization reagents to obtain circular RNA(circRNA). RNA cyclization was confirmed by agarose gel electrophoresis and ribonuclease R(RNase R)digestion. HEK-293T cells were transfected with circRNAs respectively carrying enhanced green fluorescent protein(EGFP),firefly luciferase(Fluc),and influenza virus hemagglutinin(HA)IVR-180 genes,to verify their expression with in vitro.Results With RNA cyclization,the main band of agarose gel electrophoresis became smaller and small fragments appeared. After RNase R digestion,only some circRNA bands remained.HEK-293T cells transfected with EGFP-circRNA showed significant green fluorescence under the fluorescence microscope.The Fluc expression values of HEK-293T cells transfected with Fluc-circRNA were on average 20 times higher than non cyclized RNA,and the relative light unit(RLU)scaled up with the increase of Fluc-circRNA transfection dose. Western blot analysis showed that HA protein was successfully expressed in HEK-293T cells transfected with HA-circRNA.Conclusion In this study,linear RNA was successfully cyclized in vitro and different proteins were expressed,which lays a foundation of the research of new influenza vaccines and mRNA vaccines.

Construction of competitive endogenous RNA network mediated by lung ischemia-reperfusion core genes / 器官移植

Objective To analyze the core genes of lung ischemia-reperfusion injury and construct a competitive endogenous RNA (ceRNA) network. Methods Original data of GSE145989 were downloaded from the Gene Expression Omnibus (GEO) database as the training set, and the GSE172222 and GSE9634 datasets were used as the validation sets, and the differentially-expressed genes (DEG) were identified. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed. Protein-protein interaction (PPI) network was constructed, and the core genes were screened, and the diagnostic values of these core genes and the immune infiltration levels of immune cells were evaluated. The ceRNA network was constructed and validated. The targeted drugs based on ceRNA network were assessed. Results A total of 179 DEG were identified, including 61 down-regulated and 118 up-regulated genes. GO analysis showed that DEGs were associated with multiple biological processes, such as cell migration, differentiation and regulation, etc. They were correlated with cell components, such as vesicle membrane, serosa and membrane raft, etc. They were also associated with multiple molecular functions, such as chemokine receptor, G protein-coupled receptor, immune receptor activity and antigen binding, etc. KEGG pathway enrichment analysis revealed that DEG were involved in tumor necrosis factor (TNF), Wnt, interleukin (IL)-17 and nuclear factor (NF)-κB signaling pathways, etc. PPI network suggested that CD8A, IL2RG, STAT1, CD3G and SYK were the core genes of lung ischemia-reperfusion injury. The ceRNA network prompted that miR-146a-3p, miR-28-5p and miR-593-3p were related to the expression level of CD3G. The miR-149-3p, miR-342-5p, miR-873-5p and miR-491-5p were correlated with the expression level of IL-2RG. The miR-194-3p, miR-512-3p, miR-377-3p and miR-590-3p were associated with the expression level of SYK. The miR-590-3p and miR-875-3p were related to the expression level of CD8A. The miR-143-5p, miR-1231, miR-590-3p and miR-875-3p were associated with the expression level of STAT1. There were 13 targeted drugs for CD3G, 4 targeted drugs for IL-2RG, 28 targeted drugs for SYK and 3 targeted drugs for lncRNA MUC2. No targeted drugs were identified for CD8A, STAT1 and other ceRNA network genes. Conclusions CD8A, IL2RG, STAT1, CD3G and SYK are the core genes of lung ischemia-reperfusion injury. The research and analysis of these core genes probably contribute to the diagnosis of lung ischemia-reperfusion injury and providing novel research ideas and therapeutic targets.

CircRNA Circ_0120051 Inhibits the Fibrotic Phenotype of Myocardial Fibroblasts via Targeting miR-144-3p/IDH2 Axis / 中山大学学报(医学科学版)

ObjectiveTo investigate the regulatory effect of circular RNA circ_0120051 on the fibrotic phenotype of cardiac fibroblasts and the potential mechanism involved. MethodsThe expression of circ_0120051 and its host gene of solute carrier family 8 member A1（SLC8A1） mRNA in the myocardium of healthy organ donors （n=24） and heart failure （HF） patients （n=21） were assessed by real-time quantitative polymerase chain reaction （RT-qPCR） assay. RNA stability of circ_0120051 was identified by RNase R exonuclease digestion assay. The cytoplasmic and nuclear distribution of circ_0120051 in human cardiomyocyte AC16 was detected by RT-qPCR assay. The expression of fibrosis-related genes in mouse cardiac fibroblasts （mCFs） with adenovirus-mediated overexpression of circ_0120051 was detected by RT-qPCR and Western blot assay， respectively. The effect of overexpression of circ_0120051 on the migration activity of mCFs was evaluated by wound-healing assay. RNA co-immunoprecipitation （RIP） was conducted to detect the interaction between circ_0120051 and miR-144-3p. The binding site of miR-144-3p in the 3'-UTR of isocitrate dehydrogenase 2 （Idh2） mRNA was identified by the dual luciferase reporter gene assay. ResultsCirc_0120051 was significantly up-regulated in the myocardium of HF patients， while the mRNA expression of its host gene SLC8A1 was not changed. Circ_0120051 was mainly located in the cytoplasm of human AC16 cells. Results of RNase R exonuclease digestion revealed that circ_0120051 possesses the characteristic stability of circular RNA compared to the linear SLC8A1 mRNA. Overexpression of circ_0120051 could inhibit the expression of fibrosis-related gene in mCFs and mCFs migration. RIP assay confirmed the specific interaction between circ_0120051 and miR-144-3p. Transfection of miR-144-3p mimic could efficiently promote the expression of fibrosis-related genes in mCFs and reverse the inhibitory effect of circ_0120051 on the fibrotic phenotype of mCFs. Results of the dual luciferase reporter gene assay confirmed the interaction between miR-144-3p and the 3'-UTR of Idh2. Transfection of miR-144-3p transcriptionally inhibited Idh2 expression， and overexpression of circ_0120051 enhanced IDH2 expression in mCFs. MiR-144-3p mimic and Idh2 small interfering RNA （siRNA） could consistently reverse the inhibitory effects of circ_0120051 on fibrosis-related genes expression in mCFs and mCFs migration. ConclusionsCirc_0120051 inhibits the fibrotic phenotype of cardiac fibroblasts via sponging miR-144-3p to enhance the target gene of IDH2 expression.

Peranan RNA Bulat dalam Kanser Kolorektal / Jurnal Sains Kesihatan Malaysia

@#Circular RNAs (circRNAs) are a class of non-coding RNAs formed by covalently closed loops through backsplicing. From previous studies, RNA was found to be involved in the development and formation of colorectal cancer. By emphasizing on the true function of circRNAs through focusing on its biogenesis, roles in disease treatment and roles as biomarkers, we are able to utilize circRNAs as therapy for cancer. Cancer is a chronic disease that contributes to high mortality worldwide. Colorectal cancer is one of the most common cancer in the world and in Malaysia in general. The incidence and mortality rates of colorectal cancer worldwide show a drastic and alarming increase. Colorectal cancer occurs due to mutations from certain genes involved in proliferation regulation, cell survival and cell death. This article aims to discuss the role and importance of Circular RNA in colorectal cancer. By identifying the true function of circRNAs, it can help us to develop our understanding on the real biological roles of circRNAs in colorectal cancer.

Progress of the effect of circular RNA on the sensitivity to chemotherapy drugs in colorectal cancer / 肿瘤研究与临床

The pathogenesis of colorectal cancer involves a variety of molecules and genes, among which circular RNA (circRNA) has received extensive attention in regulating the development and progression of tumors and mediating drug resistance. circNRA has been identified as tumor promoters or tumor suppressors that influence the sensitivity to chemotherapy drugs and mediate the onset and metastasis of colorectal cancer. The influence of circRNA on the drug resistance sensitivity of conventional chemotherapy has become a new direction for the research of anti-tumor chemotherapy drugs. This paper discusses the biological characteristics of circRNA and introduces the relationship between circRNA and the sensitivity to chemotherapy drugs in colorectal cancer.

Effect of circular RNA hsa_circZDHHC21_004 on the proliferation of the human small intestinal epithelial cells HIEC-6 exposed to 60Co γ-rays / 中华放射医学与防护杂志

Objective:To study the influence of circular RNA hsa_circZDHHC21_004 on the proliferation of human small intestinal epithelial cells HIEC-6 after 60Co γ-rays exposure. Methods:HIEC-6 cells were exposed to 60Co γ-rays at 0, 5, 10, and 15 Gy with a dose rate of 1 Gy/min. The expression level of hsa_circZDHHC21_004 in the irradiated HIEC-6 cell was detected. Hsa_circZDHHC21_004 was knocked-down to investigate the influences of hsa_circZDHHC21_004 on the proliferation of irradiated HIEC-6 cells by CCK-8 assay and colony formation assay. Results:The expression level of hsa_circZDHHC21_004 in HIEC-6 cells was upregulated by (1.00±0.24), (1.34±0.28), (1.85±0.31), and (2.80±0.64) times of control after 0, 5, 10, and 15 Gy irradiation, respectively and there were significant difference between 10 or 15 Gy group and 0 Gy group ( F=10.86, P=0.008). Knockdown of hsa_circZDHHC21_004 significantly increased the proliferation rate of HIEC-6 cells at 24, 48, and 72 h after 10 Gy irradiation compared with non-irradiated control ( t=-6.25, -5.83, -7.75, P < 0.001). Under 2 and 5 Gy irradiation, the clone formation rates of the hsa_circZDHHC21_004 knockdown cells were significantly higher than those of the control ( t=-7.45, -8.83, P<0.01). Conclusions:Hsa_circZDHHC21_004 is increased after irradiation and influenced the proliferation of irradiated HIEC-6 cells.

Effects of circular RNA-SEC31A on the invasion and migration of pancreatic cancer cells and molecular mechanism / 中华胰腺病杂志

Objective:To determine the expression of circular RNA-SEC31A(circSEC31A) in pancreatic cancer and investigate the effects on the invasion and migration of pancreatic cancer cells and the underlying molecular mechanism.Methods:Differentially expressed circRNAs between pancreatic cancer cells (BXPC-3, PANC1, CaPan-2, SW1990) and human normal pancreatic cells (HPDE) were identified by qRT-PCR. Then, two cell lines with high circSEC31A expression were selected to conduct next experiments. According to the sequence of the back-splicing site in circSEC31A, siRNAs for downregulation of circSEC31A were designed and transfected by liposome to silence circSEC31A in pancreatic cancer cells, and grouped as followed siR-circSEC31A#1 and siR-circSEC31A#2. Meanwhile, siR-NC group transfected with non-specific siRNA served as control. Transwell assays and wound healing assays were operated to evaluate the functional role of circSEC31A on the invasion and migration of pancreatic cancer cells. RNA Pull-down assay with circSEC31A probe and oligo control probe was used to screen the miRNA combining with circSEC31A and the effects of miRNA on cell invasion and migration of pancreatic cancer cells were validated. The effect of miR-200c-3p and circSEC31A silencing on the expression of PDK1 mRNA was identified by qRT-PCR. The protein expression of PDK1, downstream Akt and p-Akt after circSEC31A silencing was verified by Western blotting assays.Results:The relative expression level of circSEC31A in HPDE (1.000±0.120) was obviously lower than that in BXPC-3 (1.920±0.130), SW1990 (2.93±0.528), PANC1 (4.557±0.692) and CaPan-2 (5.247±0.194), and all the differences were statistically significant ( P<0.001). Compared with the PANC1 siR-NC group (1301.3±94.6) and CaPan-2 siR-NC group (1835.0±70.1) per 100 high power field, transwell assays showed that the numbers of invasive pancreatic cancer cells was highly decreased in PANC1 siR-circSEC31A#1 group (727.3±92.9), siR-circSEC31A#2 group (792.0±18.1), CaPan-2 siR-circSEC31A#1 group (718.0±90.6), siR-circSEC31A#2 group (692.7±84.8). Wound healing assays showed that silencing circSEC31A decreased the wound healing rate of pancreatic cancer cells in PANC1 siR-circSEC31A#1 group (20.667±3.215)%, siR-circSEC31A#2 group (20.000±4.583)%, CaPan-2 siR-circSEC31A#1 group (28.000±8.185)%, siR-circSEC31A#2 group (29.667±5.686)%, compared with the PANC1 siR-NC group (55.000±4.359)% and CaPan-2 siR-NC group (69.000±3.606)%. RNA Pull-down assays showed that compared with PANC1 oligo probe group (1.000±0.091) and CaPan-2 oligo probe group (1.000±0.153), miR-200c-3p was significantly enriched in the PANC1 circSEC31A probe group (2.237±0.175) and CaPan-2 circSEC31A probe group (2.166±0.156). Compared with PANC1 siR-NC group (939.3±57.0) and CaPan-2 siR-NC group (786.7±51.5) per 100 high power field, the numbers of invasive pancreatic cancer cells were up-regulated in PANC1 siR-miR-200c-3p group (1206.0±99.1) and CaPan-2 siR-miR-200c-3p group (1838.0±105.7), while the low numbers of invasive pancreatic cancer cells were observed in PANC1 siR-miR-200c-3p+ siR-circSEC31A group (932.7±116.4) and CaPan-2 siR-miR-200c-3p+ siR-circSEC31A group (785.3±58.8). Compared with PANC1 siR-NC group (1.000±0.103) and CaPan-2 siR-NC group (1.000±0.107), the relative expression of PDK1 mRNA in PANC1 siR-miR-200c-3p group (1.898±0.159) and CaPan-2 siR-miR-200c-3p group (2.102±0.337) was upregulated. Furthermore, the expression of PDK1 mRNA was decreased in the siR-miR-200c-3p+ siR-circSEC31A group (0.980±0.070, 1.015±0.079). Western blot assays showed that the expression of PDK1 protein in PANC1 siR-NC group, siR-circSEC31A#1 group, siR-circSEC31A#2 group was 0.767±0.086, 0.281±0.191, 0.333±0.062 and in CaPan-2 siR-NC group, siR-circSEC31A#1 group, siR-circSEC31A#2 group was 0.712±0.038, 0.353±0.061, 0.308±0.018. The expression of p-Akt protein in PANC1 siR-NC group and siR-circSEC31A group was 0.741±0.050, 0.114±0.027, 0.139±0.041. In addition, p-Akt protein expression in CaPan-2 siR-NC group and siR-circSEC31A group was 0.823±0.052, 0.141±0.045, 0.280±0.089. PDK1 and p Akt expression in siR circSEC31A group was obviously lower than those in sir NC group. All the differences between either groups above were statistically significant ( P<0.05). Conclusions:circSEC31A is upregulated in pancreatic cancer cells, which facilitates the invasion and metastasis of pancreatic cancer cells via miR-200c-3p/PDK1/Akt signaling pathway, supporting that circSEC31A may function as a new diagnostic and therapeutic target for pancreatic cancer patients.

Research progress on circular RNA in fundus oculi proliferative diseases / 中华实验眼科杂志

Fundus oculi proliferative diseases, such as choroidal neovascularization, diabetic retinopathy, and proliferative vitreoretinopathy, are characterized by cell proliferation and neovascularization.It can lead to damage to the ocular structure and visual acuity.Circular RNA (CircRNA) is a non-coding endogenous RNA, which has been confirmed to be involved in the pathophysiological process of many ophthalmic diseases by recent studies.Thus, circRNA may become a promising target of fundus oculi proliferative diseases.This review concluded the physiological function of circRNA and its role in the physiological and pathological process of diabetic retinopathy, proliferative vitreoretinopathy and glaucoma-related glia proliferation.

Effect of circRNA on breast cancer metastasis / 国际外科学杂志

Breast cancer is the most common malignant tumor in women, and metastasis is the main cause of death in breast cancer patients. Circular RNA (circRNA) is prevalent, abundant in organisms, and are characterized by their stable structure, conserved sequences, and specific expression. CircRNA have emerged as crucial regulators in diverse human cancers including breast cancer. Increasing evidence suggests that circRNA are aberrantly expressed in tissues and cell lines of breast cancer and involved in breast cancer metastasis. However, systematic knowledge regarding circRNA involvement in metastatic breast cancer remains unclear. This review outline functional circRNA associated with breast cancer metastasis and discuss their underlying mechanisms, providing new ideas for early prediction, diagnosis and treatment of breast cancer metastasis in the future.

The Dual Role of Non-coding RNAs in the Development of Periodontitis / 生物医学与环境科学（英文）

This review aims to sum up how Non-coding RNAs (ncRNAs) regulate the development of periodontitis and provides a new perspective for understanding the pathogenesis of periodontitis. We explored the ncRNA's dual role in the development of periodontitis by summarizing evidence from previous in vivo and in vitro studies as well as clinical samples. In our review, the downregulation of 18 miRNAs, 22 lncRNAs and 10 circRNAs demonstrates protective roles in periodontitis. In contrast, the expression of other 11 miRNAs, 7 lncRNAs and 6 circRNAs are upregulated in periodontitis, which promote the progression of periodontitis. These dysregulated ncRNAs exert their protective or destructive roles by mainly influencing cell proliferation, differentiation and apoptosis via cross-talking with various molecules or signaling pathways. Our findings suggested which and how ncRNAs promote or delay the progression of periodontitis, which may greatly contribute to diagnose and therapy development of periodontitis based on ncRNAs in the future.

Expression profiles and regulatory network of microRNA, long non-coding RNA and circular RNA in rat chronic stress depression model based on whole transcriptome technology / 解剖学报

[Abstract] Objective To explore the potential pathophysiological mechanism of depression by screening the expression profiles and competing endogenous RNA (ceRNA) regulatory network microRNA(miRNA), long non-coding RNA(lncRNA) and circular RNA (circRNA) in the hippocampus of chronic stress depression rat model. Methods Twelve SD rats were divided into blank group and model group. Chronic mild unpredictability stress (CUMS) was used to construct the rat model of depression. The whole transcriptome analysis was performed on the hippocampus of the rats, and the possible regulatory networks among lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA were explored by bioinformatics method. Results According to the | fold change | ≥1. 5 and P≤0. 05, 29 differentially expressed miRNAs (21 up-regulated and 8 down-regulated), 686 differentially expressed lncRNAs (163 up-regulated and 523 down-regulated) and 8 differentially expressed circRNAs (3 up-regulated and 5 down-regulated) were identified. Gene Ontology (GO) and Kytot Encyclopedia of Genes and Genomes(KEGG) pathway analysis showed that the target genes of miRNAs were mainly enriched in the Golgi apparatus and calcium ion binding process in the cell membrane, the functions of lncRNAs target genes involved nucleic acid binding regulation, cytokine and protein ubiquitination, etc, and the functions of host genes of circRNAs were associated with cellular stimulation response, metabolic process, catalytic activity and other processes. The ceRNA network of lncRNAs and circRNAs showed complex interactions between non-coding RNA (ncRNA) and mRNA related to synaptic plasticity, such as protein Wnt-sa(WNT5a) and collagentype III alpha1(COL8a1) related to axon orientation and laminin A2(LAMA2) related to neurodevelopment. Conclusion The ceRNA network of lncRNA and circRNA shows that the complex interaction betweens ncRNA and mRNA is highly associated with the neuroplasticity, which support the neuroplasticity hypothesis of depression.

Role and research progress of circular RNA in Alzheimer’s disease / 解剖学报

[Abstract] The circular RNA (circRNA) is a class of endogenous expressed non-coding RNA that are formed by covalently closed cyclization through reverse splicing. In recent years, a variety of highly conserved and cell-type specific circRNA have been identified in eukaryotes. Alzheimer’ s disease (AD) is a common neurodegenerative disease and the most common cause of dementia in the elderly. Recent studies had shown that circRNA was involved in the pathogenesis and development of AD, such as amyloid β-protein (Aβ) metabolic, neuroinflammation, oxidative stress, autophagy and synaptic plasticity. The role and application value of circRNA in AD pathology are reviewed to provide a theoretical basis for the application of circRNA in the treatment and diagnosis of AD.

ADAR1 regulates vascular remodeling in hypoxic pulmonary hypertension through N1-methyladenosine modification of circCDK17

Pulmonary hypertension (PH) is an extremely malignant pulmonary vascular disease of unknown etiology. ADAR1 is an RNA editing enzyme that converts adenosine in RNA to inosine, thereby affecting RNA expression. However, the role of ADAR1 in PH development remains unclear. In the present study, we investigated the biological role and molecular mechanism of ADAR1 in PH pulmonary vascular remodeling. Overexpression of ADAR1 aggravated PH progression and promoted the proliferation of pulmonary artery smooth muscle cells (PASMCs). Conversely, inhibition of ADAR1 produced opposite effects. High-throughput whole transcriptome sequencing showed that ADAR1 was an important regulator of circRNAs in PH. CircCDK17 level was significantly lowered in the serum of PH patients. The effects of ADAR1 on cell cycle progression and proliferation were mediated by circCDK17. ADAR1 affects the stability of circCDK17 by mediating A-to-I modification at the A5 and A293 sites of circCDK17 to prevent it from m1A modification. We demonstrate for the first time that ADAR1 contributes to the PH development, at least partially, through m1A modification of circCDK17 and the subsequent PASMCs proliferation. Our study provides a novel therapeutic strategy for treatment of PH and the evidence for circCDK17 as a potential novel marker for the diagnosis of this disease.

circSNRK alleviates ischemia-reperfusion injury in renal tubular epithelial cell by up-regulating Akt pathway / 器官移植

Objective To investigate the role and mechanism of circular RNA SNRK (circSNRK) in ischemia-reperfusion injury (IRI). Methods A hypoxia-reoxygenation (IRI) cell model was established. The expression level of circSNRK after IRI treatment and the effect of overexpression of circSNRK on cell proliferation and apoptosis were detected. The targets of circSNRK were identified. HK2 cells were divided into the blank group (Mock group), IRI group, control plasmid+IRI group (IRI+NC group), human circSNRK overexpression+IRI group (IRI+circSNRK group), human circSNRK overexpression+IRI+protein kinase B (Akt) inhibitor group (IRI+circSNRK+MK2206 group) and control plasmid group (NC group). Cell proliferation and apoptosis were detected in the Mock, IRI, IRI+NC and IRI+circSNRK groups. The gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of the target of circSNRK were carried out. The expression levels of CDKN1A, Akt, B-cell lymphoma (Bcl)-2, cysteinyl aspartate specific proteinase (Caspase)-9 messenger RNA (mRNA), and those of p21, Bcl-2, Caspase-9, Akt and p-Akt proteins were detected in the Mock, IRI, IRI+NC and IRI+circSNRK groups, respectively. Cell proliferation and apoptosis were determined in the NC, IRI+NC, IRI+circSNRK and IRI+circSNRK+MK2206 groups. Results Compared with the Mock group, the expression level of circSNRK was lower, and cell proliferation capability of HK2 cells was decreased and cell apoptosis was increased in the IRI group. In the IRI+circSNRK group, cell proliferation capability was higher, whereas cell apoptosis was lower than those in the IRI+NC group. circSNRK could act on 648 targets through 51 microRNAs (miRNAs). GO enrichment analysis revealed that the targets of circSNRK were mainly enriched in biological processes (such as cell process and biological regulation), cell components (such as cell parts, cells and extracellular parts), and molecular functions (such as binding, binding proteins and enzymes). KEGG enrichment analysis showed that the targets of circSNRK were mainly enriched in cancer signaling pathway, phosphatidylinositol 3-kinase (PI3K)-Akt signaling pathway, miRNA in cancer and other related signaling pathways. Compared with the Mock group, the relative expression levels of CDKN1A and Caspase-9 mRNA were higher, the expression level of miR-99a-5p RNA was higher and the relative expression levels of Akt and Bcl-2 mRNA were lower in the IRI group. Compared with the IRI+NC group, the relative expression levels of CDKN1A and Caspase-9 mRNA were lower, those of Akt and Bcl-2 mRNA were higher, and the expression level of miR-99a-5p RNA was lower in the IRI+circSNRK group, and the differences were statistically significant (all P < 0.05). Compared with the Mock group, the expression levels of p21 and Caspase-9 proteins were higher, while those of p-Akt, Akt and Bcl-2 proteins were lower in the IRI group. Compared with the IRI+NC group, the expression levels of p21 and Caspase-9 proteins were lower, whereas those of p-Akt, Akt and Bcl-2 proteins were higher in the IRI+circSNRK group. The miR-99a-5p binding sites were observed in circSNRK and Akt. Compared with the NC group, cell proliferation capability was declined in the IRI+NC group. Compared with the IRI+NC group, cell proliferation capability was elevated in the IRI+circSNRK group. Compared with the IRI+circSNRK group, cell proliferation capability was declined in the IRI+circSNRK+MK2206 group (all P < 0.05). The cell apoptosis level in the IRI+NC group was higher than that in the NC group. The cell apoptosis level in the IRI+circSNRK group was lower compared with that in the IRI+NC group. The cell apoptosis level in the IRI+circSNRK+MK2206 group was higher than that in the IRI+circSNRK group. Conclusions Under IRI conditions, circSNRK may affect the proliferation and apoptosis of HK2 cells probably via the Akt signaling pathway.

Regulation of Glial Function by Noncoding RNA in Central Nervous System Disease / 神经科学通报·英文版

Non-coding RNAs (ncRNAs) are a class of functional RNAs that play critical roles in different diseases. NcRNAs include microRNAs, long ncRNAs, and circular RNAs. They are highly expressed in the brain and are involved in the regulation of physiological and pathophysiological processes of central nervous system (CNS) diseases. Mounting evidence indicates that ncRNAs play key roles in CNS diseases. Further elucidating the mechanisms of ncRNA underlying the process of regulating glial function that may lead to the identification of novel therapeutic targets for CNS diseases.

Circular RNA circRSF1 binds to HuR to promote radiation-induced inflammatory phenotype in hepatic stellate cells / 南方医科大学学报

OBJECTIVE@#To investigate whether circular RNA circRSF1 regulates radiation-induced inflammatory phenotype of hepatic stellate cells (HSCs) by binding to HuR protein and repressing its function.@*METHODS@#Human HSC cell line LX2 with HuR overexpression or knockdown was exposed to 8 Gy X-ray irradiation, and the changes in the expression of inflammatory factors (IL-1β, IL-6 and TNF-α) were detected by qRT-PCR. The expressions of IκBα and phosphorylation of NF-κB were detected with Western blotting. The binding of circRSF1 to HuR was verified by RNA pull-down assay and RNA-binding protein immunoprecipitation (RIP). The expressions of inflammatory factors, IκBα and the phosphorylation of NF-κB were detected after modifying the interaction between circRSF1 and HuR.@*RESULTS@#Knockdown of HuR significantly up- regulated the expressions of IL-1β, IL-6 and TNF-α, decreased IκBα expression and promoted NF-κB phosphorylation in irradiated LX2 cells, whereas overexpression of HuR produced the opposite changes (P < 0.05). Overexpression or knockdown of circRSF1 did not significantly affect the expression of HuR. RNA pull-down and RIP experiments confirmed the binding between circRSF1 and HuR. Overexpression of circRSF1 significantly reduced the binding of HuR to IκBα and down-regulated the expression of IκBα (P < 0.05). Overexpression of circRSF1 combined with HuR overexpression partially reversed the up-regulation of the inflammatory factors, down-regulated IκBα expression and increased phosphorylation of NFκB in LX2 cells, while the opposite effects were observed in cells with knockdown of both circRSF1 and HuR (P < 0.05).@*CONCLUSION@#circRSF1 reduces IκBα expression by binding to HuR to promote the activation of NF-κB pathway, thereby enhancing radiation- induced inflammatory phenotype of HSCs.

Promising roles of non-exosomal and exosomal non-coding RNAs in the regulatory mechanism and as diagnostic biomarkers in myocardial infarction / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Non-exosomal non-coding RNAs (non-exo-ncRNAs) and exosomal ncRNAs (exo-ncRNAs) have been associated with the pathological development of myocardial infarction (MI). Accordingly, this analytical review provides an overview of current MI studies on the role of plasma non-exo/exo-ncRNAs. We summarize the features and crucial roles of ncRNAs and reveal their novel biological correlations via bioinformatics analysis. The following contributions are made: (1) we comprehensively describe the expression profile, competing endogenous RNA (ceRNA) network, and "pre-necrotic" biomarkers of non-exo/exo-ncRNAs for MI; (2) functional enrichment analysis indicates that the target genes of ncRNAs are enriched in the regulation of apoptotic signaling pathway and cellular response to chemical stress, etc.; (3) we propose an updated and comprehensive view on the mechanisms, pathophysiology, and biomarker roles of non-exo/exo-ncRNAs in MI, thereby providing a theoretical basis for the clinical management of MI.

Role of ceRNA network in inflammatory cells of rheumatoid arthritis / 中南大学学报(医学版)

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease caused by inflammatory cells. Various inflammatory cells involved in RA include fibroblast-like synoviocytes, macrophages, CD4+T-lymphocytes, B lymphocytes, osteoclasts and chondrocytes. The close interaction between various inflammatory cells leads to imbalance of immune response and disorder of the expression of mRNA in inflammatory cells. It helps to drive production of pro-inflammatory cytokines and stimulate specific antigen-specific T- and B-lymphocytes to produce autoantibodies which is an important pathogenic factor for RA. Competing endogenous RNA (ceRNA) can regulate the expression of mRNA by competitively binding to miRNA. The related ceRNA network is a new regulatory mechanism for RNA interaction. It has been found to be involved in the regulation of abnormal biological processes such as proliferation, apoptosis, invasion and release of inflammatory factors of RA inflammatory cells. Understanding the ceRNA network in 6 kinds of RA common inflammatory cells provides a new idea for further elucidating the pathogenesis of RA, and provides a theoretical basis for the discovery of new biomarkers and effective therapeutic targets.

Recent Research Progress on CircRNA in Hematological Malignancies--Review / 中国实验血液学杂志

Most hematological tumors have high-grade malignancy and low cure rate, requiring new molecular markers for detection and evaluation. Circular RNAs (circRNAs) are a class of non-coding RNAs with covalently closed-loop structures, which participate in gene transcription and translation by binding to microRNAs and proteins. In recent years, with the deepening research on circRNAs, circRNAs have been found to play an important role in hematological malignancies. In this review, the latest research progress on the function and molecular mechanism of circRNAs in hematological malignancies was systematically summarized, and it was found that circRNAs may be potential new biomarkers and therapeutic targets in hematological malignancies.