BACKGROUND: Dysfunction of the gap junction channel protein connexin 43 (Cx43) contributes to myocardial ischemia/reperfusion (I/R)-induced ventricular arrhythmias. Cx43 can be regulated by small ubiquitin-like modifier (SUMO) modification. Protein inhibitor of activated STAT Y (PIASy) is an E3 SUMO ligase for its target proteins. However, whether Cx43 is a target protein of PIASy and whether Cx43 SUMOylation plays a role in I/R-induced arrhythmias are largely unknown. METHODS: Male Sprague-Dawley rats were infected with PIASy short hairpin ribonucleic acid (shRNA) using recombinant adeno-associated virus subtype 9 (rAAV9). Two weeks later, the rats were subjected to 45 min of left coronary artery occlusion followed by 2 h reperfusion. Electrocardiogram was recorded to assess arrhythmias. Rat ventricular tissues were collected for molecular biological measurements. RESULTS: Following 45 min of ischemia, QRS duration and QTc intervals statistically significantly increased, but these values decreased after transfecting PIASy shRNA. PIASy downregulation ameliorated ventricular arrhythmias induced by myocardial I/R, as evidenced by the decreased incidence of ventricular tachycardia and ventricular fibrillation, and reduced arrythmia score. In addition, myocardial I/R statistically significantly induced PIASy expression and Cx43 SUMOylation, accompanied by reduced Cx43 phosphorylation and plakophilin 2 (PKP2) expression. Moreover, PIASy downregulation remarkably reduced Cx43 SUMOylation, accompanied by increased Cx43 phosphorylation and PKP2 expression after I/R. CONCLUSION PIASy downregulation inhibited Cx43 SUMOylation and increased PKP2 expression, thereby improving ventricular arrhythmias in ischemic/reperfused rats heart.
Rats ; Male ; Animals ; Myocardial Reperfusion Injury/metabolism* ; Connexin 43/genetics* ; Sumoylation ; Down-Regulation ; Rats, Sprague-Dawley ; Arrhythmias, Cardiac/drug therapy* ; Myocardial Ischemia/metabolism* ; RNA, Small Interfering/metabolism*

Objective: To screen the key genes involved in gefitinib resistance of lung adenocarcinoma PC9/GR cells which harbored 19 exon mutation of epidermal growth factor receptor (EGFR) gene, and discuss the effect and mechanism of downregulation of solute carrier family 7 member 11 (SLC7A11) on the gefitinib resistance of PC9/GR cells. Methods: RNA microarray was conducted to detect the gene expressions in PC9 and PC9/GR cells. The differently expressed genes were screened by using limma package of R language and analyzed by Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis. Western blotting was performed to determine the expression of SLC7A11 protein in PC9 and PC9/GR cells. PC9/GR cells were infected with lentivirus plasmid containing short hairpin RNA (shRNA) targeting SLC7A11 or negative control shRNA (sh-NC), respectively. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to evaluate the efficacy of shRNA on the expression of SLC7A11 mRNA. Cell counting kit-8 (CCK-8) assay was conducted to determine the suppressing effect of gefitinib on PC9/GR cells. Mito-Tracker Red CMXRos probe and malondialdehyde (MDA) assay kit were used to evaluate gefitinib-induced ferroptosis in PC9/GR cells. Immunohistochemistry (IHC) was conducted to detect the expression of SLC7A11 protein in the tumor tissues of advanced stage lung adenocarcinoma patients harboring 19 exon mutation of EGFR gene. Thirty-six advanced stage lung adenocarcinoma patients who received EGFR-tyrosihe kinase inhibitor(TKI) as first-line treatment in Fourth Hospital of Hebei Medical Unviersity were enrolled. Kaplan-Meier survival curve was drawn to analyze the correlation between SLC7A11 expression and progression-free survival (PFS) of the patients. Results: RNA array demonstrated that 2 888 genes were differently expressed between PC9 and PC9/GR cells. KEGG analysis showed that ferroptosis-related gene was one of the most enriched region of the differently expressed genes between PC9 and PC9/GR cells. These ferroptosis-related gene cohort contained 13 genes, among which SLC7A11 exhibited the most significant difference. Western blotting showed that the expression of SLC7A11 protein in PC9/GR cells was significantly higher than that in PC9 cells (0.76±0.03 vs. 0.19±0.02, P<0.001). The 50% inhibiting concentration (IC(50)) of gefitinib was 35.08 μmol/L and 64.01 μmol/L for sh-SLC7A11 and sh-NC group PC9/GR cells, respectively. PC9/GR cells in sh-SLC7A11 group exhibited significantly lower density of mitochondria fluorescence after gefitinib treatment, compared to the sh-NC group (213.77±26.50 vs. 47.88±4.55, P<0.001). In addition, PC9/GR cells in sh-SLC7A11 group exhibited significantly higher MDA after gefitinib treatment, compared to the sh-NC group [(15.43±1.60) μmol/mg vs. (82.18±7.77) μmol/mg, P<0.001]. The PFS of the patients with low expression of SLC7A11 (n=18) was significantly longer than the patients with high expression of SLC7A11 (n=18, 16.77 months vs. 9.14 months, P<0.001). Conclusion: Downregulation of SLC7A11 could increase the sensitivity of PC9/GR cells to gefitinib by promoting ferroptosis.
Humans ; Gefitinib/therapeutic use* ; Antineoplastic Agents/therapeutic use* ; Lung Neoplasms/pathology* ; Down-Regulation ; Quinazolines/therapeutic use* ; Drug Resistance, Neoplasm/genetics* ; ErbB Receptors/metabolism* ; Adenocarcinoma of Lung ; Protein Kinase Inhibitors/therapeutic use* ; RNA, Small Interfering/genetics* ; Cell Line, Tumor ; Amino Acid Transport System y+/metabolism*

BACKGROUND: Excessive proliferation and migration of vascular smooth muscle cells (VSMCs) are the main causes of restenosis (RS) in diabetic lower extremity arterial disease (LEAD). However, the relevant pathogenic mechanisms are poorly understood. METHODS: In this study, we introduced a "two-step injury protocol" rat RS model, which started with the induction of atherosclerosis (AS) and was followed by percutaneous transluminal angioplasty (PTA). Hematoxylin-eosin (HE) staining and immunohistochemistry staining were used to verify the form of RS. Two-step transfection was performed, with the first transfection of Lin28a followed by a second transfection of let-7c and let-7g, to explore the possible mechanism by which Lin28a exerted effects. 5-ethynyl-2΄-deoxyuridine (EdU) and Transwell assay were performed to evaluate the ability of proliferation and migration of VSMCs. Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to detect the expression of Lin28a protein and let-7 family members. RESULTS: Using a combination of in vitro and in vivo experiments, we discovered that let-7c, let-7g, and microRNA98 (miR98) were downstream targets of Lin28a. More importantly, decreased expression of let-7c/let-7g increased Lin28a, leading to further inhibition of let-7c/let-7g. We also found an increased level of let-7d in the RS pathological condition, suggesting that it may function as a protective regulator of the Lin28a/let-7 loop by inhibiting the proliferation and migration of VSMCs. CONCLUSION These findings indicated the presence of a double-negative feedback loop consisting of Lin28a and let-7c/let-7g, which may be responsible for the vicious behavior of VSMCs in RS.
Rats ; Animals ; Down-Regulation ; MicroRNAs/metabolism* ; Feedback ; Cell Proliferation/genetics* ; Atherosclerosis

OBJECTIVE: Circular RNAs (circRNAs) participate in several important pathological processes and have been used in the diagnosis and treatment of various diseases. This study aimed to investigate the role of circRNAs in neural tube defects (NTDs). METHOD: We characterized circRNA-associated competitive endogenous RNA (ceRNA) networks in brain tissue of low folate -induced NTDs mouse at embryonic day 13.5 by high-throughput sequencing. The expression levels of Circzfp644, miR-20-5p and Gas7 were detected by RT-PCR. Gas7 and Circzfp644 functions were determined by miRNA-mimics and inhibitors in mouse teratocarcinoma cells (F9 cells), and luciferase gene reporter assay was assessed in the F9 cells. In addition, the expression levels of Circzfp644, miR-20-5p and Gas7 were determined by Nanostring in human NTDs tissues. RESULTS: We detected 57 circRNA transcripts, 16 miRNAs, and 148 mRNAs that were significantly dysregulated in NTDs brain tissues compared with their expression levels in control (normal) tissues. Circzfp644 shared miRNA response elements with the growth arrest specific 7 ( Gas7) gene and competitively bound with miR-20-5p to increase the expression of Gas7. Downregulation of Circzfp644 and Gas7 and upregulation of miR-20-5p were found in human NTD tissue. CONCLUSION This study provides new perspectives on the role of circRNAs in nervous system development and the pathogenesis of NTDs.
Humans ; Animals ; Mice ; RNA, Circular/genetics* ; MicroRNAs/metabolism* ; Down-Regulation ; Neural Tube Defects/genetics* ; Folic Acid

OBJECTIVES: Graves' ophthalmopathy (GO) is a multifactorial disease, and the mechanism of non coding RNA interactions and inflammatory cell infiltration patterns are not fully understood. This study aims to construct a competing endogenous RNA (ceRNA) network for this disease and clarify the infiltration patterns of inflammatory cells in orbital tissue to further explore the pathogenesis of GO. METHODS: The differentially expressed genes were identified using the GEO2R analysis tool. The Kyoto encyclopedia of genes and genomes (KEGG) and gene ontology analysis were used to analyze differential genes. RNA interaction relationships were extracted from the RNA interactome database. Protein-protein interactions were identified using the STRING database and were visualized using Cytoscape. StarBase, miRcode, and DIANA-LncBase Experimental v.2 were used to construct ceRNA networks together with their interacted non-coding RNA. The CIBERSORT algorithm was used to detect the patterns of infiltrating immune cells in GO using R software. RESULTS: A total of 114 differentially expressed genes for GO and 121 pathways were detected using both the KEGG and gene ontology enrichment analysis. Four hub genes (SRSF6, DDX5, HNRNPC,and HNRNPM) were extracted from protein-protein interaction using cytoHubba in Cytoscape, 104 nodes and 142 edges were extracted, and a ceRNA network was identified (MALAT1-MIR21-DDX5). The results of immune cell analysis showed that in GO, the proportions of CD8⁺ T cells and CD4⁺ memory resting T cells were upregulated and downregulated, respectively. The proportion of CD4 memory resting T cells was positively correlated with the expression of MALAT1, MIR21, and DDX5. CONCLUSIONS This study has constructed a ceRNA regulatory network (MALAT1-MIR21-DDX5) in GO orbital tissue, clarifying the downregulation of the proportion of CD4⁺ stationary memory T cells and their positive regulatory relationship with ceRNA components, further revealing the pathogenesis of GO.
Humans ; CD8-Positive T-Lymphocytes ; RNA, Long Noncoding/genetics* ; Algorithms ; CD4-Positive T-Lymphocytes ; Down-Regulation ; Graves Ophthalmopathy/genetics* ; Gene Regulatory Networks ; MicroRNAs/genetics* ; Serine-Arginine Splicing Factors ; Phosphoproteins

Objective: To screen the key genes involved in gefitinib resistance of lung adenocarcinoma PC9/GR cells which harbored 19 exon mutation of epidermal growth factor receptor (EGFR) gene, and discuss the effect and mechanism of downregulation of solute carrier family 7 member 11 (SLC7A11) on the gefitinib resistance of PC9/GR cells. Methods: RNA microarray was conducted to detect the gene expressions in PC9 and PC9/GR cells. The differently expressed genes were screened by using limma package of R language and analyzed by Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis. Western blotting was performed to determine the expression of SLC7A11 protein in PC9 and PC9/GR cells. PC9/GR cells were infected with lentivirus plasmid containing short hairpin RNA (shRNA) targeting SLC7A11 or negative control shRNA (sh-NC), respectively. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to evaluate the efficacy of shRNA on the expression of SLC7A11 mRNA. Cell counting kit-8 (CCK-8) assay was conducted to determine the suppressing effect of gefitinib on PC9/GR cells. Mito-Tracker Red CMXRos probe and malondialdehyde (MDA) assay kit were used to evaluate gefitinib-induced ferroptosis in PC9/GR cells. Immunohistochemistry (IHC) was conducted to detect the expression of SLC7A11 protein in the tumor tissues of advanced stage lung adenocarcinoma patients harboring 19 exon mutation of EGFR gene. Thirty-six advanced stage lung adenocarcinoma patients who received EGFR-tyrosihe kinase inhibitor(TKI) as first-line treatment in Fourth Hospital of Hebei Medical Unviersity were enrolled. Kaplan-Meier survival curve was drawn to analyze the correlation between SLC7A11 expression and progression-free survival (PFS) of the patients. Results: RNA array demonstrated that 2 888 genes were differently expressed between PC9 and PC9/GR cells. KEGG analysis showed that ferroptosis-related gene was one of the most enriched region of the differently expressed genes between PC9 and PC9/GR cells. These ferroptosis-related gene cohort contained 13 genes, among which SLC7A11 exhibited the most significant difference. Western blotting showed that the expression of SLC7A11 protein in PC9/GR cells was significantly higher than that in PC9 cells (0.76±0.03 vs. 0.19±0.02, P<0.001). The 50% inhibiting concentration (IC(50)) of gefitinib was 35.08 μmol/L and 64.01 μmol/L for sh-SLC7A11 and sh-NC group PC9/GR cells, respectively. PC9/GR cells in sh-SLC7A11 group exhibited significantly lower density of mitochondria fluorescence after gefitinib treatment, compared to the sh-NC group (213.77±26.50 vs. 47.88±4.55, P<0.001). In addition, PC9/GR cells in sh-SLC7A11 group exhibited significantly higher MDA after gefitinib treatment, compared to the sh-NC group [(15.43±1.60) μmol/mg vs. (82.18±7.77) μmol/mg, P<0.001]. The PFS of the patients with low expression of SLC7A11 (n=18) was significantly longer than the patients with high expression of SLC7A11 (n=18, 16.77 months vs. 9.14 months, P<0.001). Conclusion: Downregulation of SLC7A11 could increase the sensitivity of PC9/GR cells to gefitinib by promoting ferroptosis.
Humans ; Gefitinib/therapeutic use* ; Antineoplastic Agents/therapeutic use* ; Lung Neoplasms/pathology* ; Down-Regulation ; Quinazolines/therapeutic use* ; Drug Resistance, Neoplasm/genetics* ; ErbB Receptors/metabolism* ; Adenocarcinoma of Lung ; Protein Kinase Inhibitors/therapeutic use* ; RNA, Small Interfering/genetics* ; Cell Line, Tumor ; Amino Acid Transport System y+/metabolism*

OBJECTIVE: To explore the effect and mechanism of down-regulating lncRNA TTTY15 targeting miR-4500 on the proliferation, apoptosis, migration and invasion of A172 glioma cells. METHODS: The difference in TTTY15 expression between the glioma cells and tissue was determined with a qRT-PCR method. Complementary binding sites of TTTY15 and miR-4500 were predicted with Starbase software, and the targeting relationship was validated with a luciferase reporter system. A172 glioma cells were divided into Control, si-NC (transfected with control siRNA), si-TTTY15 (transfected with TTTY15 siRNA), si-TTTY15+Anti-miR-NC (co-transfected with TTTY15 siRNA and inhibitor control) and si-TTTY15+Anti-miR-4500 (co-transfected with TTTY15 siRNA and miR-4500 inhibitor) groups. Proliferation, apoptosis, migration and invasion, and the expression of Bax, Bcl-2, MMP-2 and MMP-9 proteins of the A172 glioma cells were respectively detected with CCK-8, flow cytometry, Transwell chamber and Western blotting assays. RESULTS: The expression of TTTY15 in glioma cells and glioma tissues have both increased. The expression levels of TTTY15 and miR-4500 in glioma tissues were inversely correlated. TTTY15 and miR-4500 are mutually targeted. Compared with those of the Control and si-NC groups, the glioma cells in the si-TTTY15 group showed increased level of miR-4500, decreased survival rate, increased apoptosis rate, enhanced cell migration and invasion, increased expression of Bax protein, and decreased expression of Bcl-2, MMP-2 and MMP-9 proteins (P<0.05). Compared with those of the si-TTTY15+Anti-miR-NC group, the A172 glioma cells in the si-TTTY15+Anti-miR-4500 group showed decreased level of miR-4500, increased cell survival rate, decreased apoptosis rate, enhanced cell migration and invasion, decreased expression of Bax protein, and increased expression of Bcl-2, MMP-2, and MMP-9 proteins (P<0.05). CONCLUSION Down-regulating TTTY15 targeting miR-4500 can inhibit the proliferation, migration, invasion and induce apoptosis of the A172 glioma cells.
Apoptosis/genetics* ; Cell Line, Tumor ; Cell Movement/genetics* ; Cell Proliferation ; Down-Regulation ; Gene Expression Regulation, Neoplastic ; Glioma/genetics* ; Humans ; MicroRNAs/genetics* ; RNA, Long Noncoding

OBJECTIVE: To investigate whether miR-125b-5p regulates biological behaviors of ovarian cancer cells by targeted regulation of CD147 expression. METHODS: RT-qPCR was used to detect the expression of miR-125b-5p and CD147 mRNA in ovarian cancer tissues and cancer cell lines. SKOV3 cells transfected with miR-125b-5p mimic and HO8910 cells transfected with miR-125b-5p inhibitor were examined for changes in proliferation, migration and invasion using CCK-8 assay, colonyforming assay and Transwell assay. Starbase was used to predict the potential binding sites between miR-125b-5p and CD147, and double luciferase reporter gene assay was used to verify the targeting relationship. In SKOV3 cells, the effects of cotransfection with miR-125b-5p mimic and pcDNA3.1-CD147 (or pcDNA3.1) plasmid on cell proliferation, migration and invasion were assessed with CCK-8 assay and Transwell assay. RESULTS: The expression of miR-125b-5p was significantly lowered and that of CD147 was increased in both ovarian cancer tissues and ovarian cancer cell lines (P < 0.05). Overexpression of miR-125b-5p in SKOV3 cells resulted in significantly suppressed cell proliferation, migration and invasion, while downregulation of miR-125b-5p in HO8910 cells promoted cell proliferation, migration and invasion. Bioinformatic analysis predicted that miR-125b-5p binds to CD147, which was confirmed by luciferase reporter gene assay. RT-qPCR and Western blotting showed that miR-125b-5p negatively regulated CD147 expression (P < 0.05). In SKOV3 cells, the inhibitory effects of miR-125b-5p mimic on cell proliferation, invasion and migration were significantly attenuated by co-transfection of the cells with pcDNA3.1-CD147 plasmid. CONCLUSION miR-125b-5p inhibits the migration and invasion of ovarian cancer cells by negatively regulating the expression of CD147.
Basigin ; Carcinoma, Ovarian Epithelial ; Cell Line, Tumor ; Cell Movement/genetics* ; Cell Proliferation/genetics* ; Down-Regulation ; Female ; Gene Expression Regulation, Neoplastic ; Humans ; MicroRNAs/metabolism* ; Neoplasm Invasiveness/genetics* ; Ovarian Neoplasms/genetics* ; RNA, Messenger/genetics* ; Sincalide/metabolism*

OBJECTIVE: To investigate the down-regulation of ANRIL (Antisense non-coding RNA in the INK4 Locus) effects on proliferation and apoptosis of Kasumi-1 cells and its related molecular mechanism. METHODS: Recombinant lentivirus was used to construct ANRIL down-regulation Kasumi-1 cells (sh-ANRIL group) and its control cells (sh-NC group). A fluorescence microscope was used to observe the transfection efficiency, RT-qPCR was used to detect knockdown efficiency and ANRIL expression in PBMCs and MBMCs of patients with acute myeloid leukemia (AML). Proliferation and apoptosis of Kasumi-1 cells were assayed by CCK-8 method and flow cytometry. Western blot was employed to detect the expression of PI3K, AKT, p-AKT, and relevant protein after down-regulation of ANRIL in Kasumi-1 cells. RESULTS: ANRIL overexpressed significantly in PBMCs and MBMCs of patients with AML, the transfection efficiency of recombinant lentivirus carrying sh-ANRIL and sh-NC on Kasumi-1 cells exceeded 90%, and the knockdown efficiency was 70%. When DNR was administrated for 24, 48, and 72 hours, the cell inhibition rate of the sh-ANRIL group was (47.40±1.49)%, (69.11±0.51)% and (91.82±1.10)%, which were significantly higher than those of the sh-NC group, respectively (P<0.05). The apoptotic rate in the sh-ANRIL group was (10.29±0.58)%, which was significantly higher than (5.42±0.67)% of the sh-NC group (P<0.01). After DNR treatment for 24 hours, the apoptotic rate of the sh-ANRIL group was (54.41±1.69)%, which was significantly higher than (38.28±1.42)% of sh-NC group (P<0.001). Western blot revealed that the protein levels of PI3K, p-AKT, PCNA, and BCL-2 in the sh-ANRIL group were reduced significantly than those in the sh-NC group, while the BAX protein expression increased. CONCLUSION ANRIL may affect the proliferation and apoptosis of Kasumi-1 cells through PI3K/AKT signaling pathway. ANRIL is a potential therapeutic target for AML.
Apoptosis ; Cell Line, Tumor ; Cell Proliferation ; Down-Regulation ; Humans ; Leukemia, Myeloid, Acute/genetics* ; Phosphatidylinositol 3-Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/genetics* ; RNA, Long Noncoding/genetics*

OBJECTIVE: To observe the effects of down-regulation of long non-coding RNA HOX antisense intergenic RNA myeloid 1 (LncRNA-HOTAIRM1) to the proliferation and apoptosis of Jurkat in human leukemia T lymphocytes, and explore its mechanism. METHODS: Jurkat cells were cultured in vitro and randomly divided into control group, HOTAIRM1 siRNA-NC group and HOTAIRM1 siRNA group; the expressions of LncRNA-HOTAIRM1 mRNA, KIT receptor tyrosine kinase (KIT) mRNA and serine threonine kinase (AKT) mRNA in Jurkat cells were detected by real-time fluorescence quantification (RT-qPCR); the proliferation of Jurkat cells in each groups was detected by CCK-8 method; the apoptosis of Jurkat cells in each groups was detected by Annexin V-FITC/PI double staining; the expressions of KIT, AKT, p-KIT, p-AKT, B-lymphoma-2 gene (BCL-2) and Caspase-3 were detected by Western blot. RESULTS: Compared with the cells in the control group and HOTAIRM1 siRNA-NC group, the expression level of LncRNA-HOTAIRM1 mRNA, cell survival rate, expression levels of KIT mRNA, AKT mRNA, p-KIT, p-AKT and BCL-2 proteins in Jurkat cells in HOTAIRM1 siRNA group were significantly lower (P<0.05), while the expression level of Cleared Caspase-3 protein and Jurkat cell apoptosis rate were significantly higher (P<0.05). CONCLUSION LncRNA-HOTAIRM1 may inhibit Jurkat cell proliferation and induce apoptosis through KIT/AKT signaling pathway.
Apoptosis ; Cell Proliferation ; Down-Regulation ; Humans ; Jurkat Cells ; Proto-Oncogene Proteins c-akt/metabolism* ; RNA, Long Noncoding/genetics*