PVT1 Knockdown Research Articles

Long Non-Coding RNA PVT1 Facilitates Radiation-Induced Vascular Endothelial Cell Injury through Sponging MicroRNA-9-5p.

Radiotherapy is a common therapeutic strategy for various solid tumors, with vascular endothelial injury being a common side effect. The study aimed to examine the effect of long non-coding RNA PVT1 on radiation-induced vascular endothelial cell injury, and explore the possible underlying mechanism. Human umbilical vein endothelial cells (HUVECs) were exposed to different doses of X ray to mimic radiation. LncRNA and miRNA levels were detected via qRT-PCR. Interaction between lncRNA and miRNAs was determined through dual-luciferase reporter assay. Statistical processing was conducted using student's t test between two groups and one-way ANOVA among multiple groups, and P < 0.05 means a significant difference. GO and KEGG were performed for the function and pathway enrichment analysis. LncRNA PVT1 elevated along with the increase of radiation dose in HUVECs. Poorly expressed lncRNA PVT1 promotes cell viability and inhibits oxidative stress. PVT1 serves as a competitive endogenous RNA (ceRNA) of miR-9-5p. miR-9-5p inhibitor inverted the influence of PVT1 knockdown on radiation-stimulated cell apoptosis and oxidative stress in HUVECs. KEGG analysis identified significant enrichment of the MAPK signaling pathway among overlapping target genes of miR-9-5p. LncRNA PVT1 knockdown alleviated radiation-induced vascular endothelial injury via sponging miR-9-5p. The underlying mechanism might be probably MAPK signaling-related.

LncRNA Pvt1 aggravates cardiomyocyte apoptosis via the microRNA-216/Ccnd3 axis

ObjectiveOur study aims to evaluate the role of long non-coding RNA variant translocation gene Pvt1 in cardiomyocyte apoptosis, as well as the potential targets and mechanisms involved in Pvt1-miRNA-mRNA axis. Methods1.Pvt1 knockdown in cells by transfection with small interfering RNA (si-Pvt1), HL-1 cells were randomly divided into control group, hypoxia group, hypoxia + negative control group and hypoxia + si-Pvt1 group. Apoptosis-related genes expression was detected by Western blot assay, RT-qPCR and Flow cytometry assay. 2.Pvt1 knockdown model (sh-Pvt1) was established by injecting adeno-associated virus (AAV) vector shRNA-Pvt1 into the caudal vein 7 days before myocardial infarction, and echocardiography was used to measure cardiac function 7 days after myocardial infarction induced by ligation of the left anterior descending branch. HE staining was used to evaluate the pathological injury of mouse heart tissue, and the apoptotic protein expression was detected by Western blot. 3.lncRNA-related microRNAs were predicted by bioinformatics tools and further verified by dual luciferase experiment. Western blot analysis was used to identify the expression of apoptotic genes following the simultaneous transfection of si-Pvt1 and miR-216 mimics. Genes differentially expressed in hypoxia + si-NC and hypoxia + si-Pvt1 groups were identified by RNA sequencing. These genes were then compared with the target genes of miR-216 predicted by bioinformatics tools. The gene of interest Ccnd3 was excluded from the analysis. Western blot analysis was used to assess the expression of Apoptosis-related proteins in HL-1 cells co-transfected with miR-216 mimics and overexpressed Ccnd3. Results1. Pvt1 was highly expressed in HL-1 induced by hypoxia, and Pvt1 knockdown can reduce cell apoptosis in hypoxia cells. 2. MI causes myocardial injury in mice, and inhibition of Pvt 11 can improve the cardiac function of mice with myocardial infarction, prevent some inflammatory cell infiltration, and reduce myocardial cell apoptosis. 3. Pvt1 acts as a sponge for miR-216 and promotes the expression of Ccnd3. ConclusionPvt1 may promote myocardial infarct-induced apoptosis through the miR-216/Ccnd3 axis.

Lnc PVT1 facilitates TGF-β1-induced human cardiac fibroblast activation in vitro and ISO-induced myocardial fibrosis in vivo through regulating MYC.

Cardiac fibrosis is a commonly seen pathophysiological process in various cardiovascular disorders, such as coronary heart disorder, hypertension, and cardiomyopathy. Cardiac fibroblast trans-differentiation into myofibroblasts (MFs) is a key link in myocardial fibrosis. LncRNA PVT1 participates in fibrotic diseases in multiple organs; however, its role and mechanism in cardiac fibrosis remain largely unknown. Human cardiac fibroblasts (HCFs) were stimulated with TGF-β1 to induce myofibroblast; Immunofluorescent staining, Immunoblotting, and fluorescence in situ hybridization were used to detect the myofibroblasts phenotypes and lnc PVT1 expression. Cell biological phenotypes induced by lnc PVT1 knockdown or overexpression were detected by CCK-8, flow cytometry, and Immunoblotting. A mouse model of myocardial fibrosis was induced using isoproterenol (ISO), and the cardiac functions were examined by echocardiography measurements, cardiac tissues by H&E, and Masson trichrome staining. In this study, TGF-β1 induced HCF transformation into myofibroblasts, as manifested as significantly increased levels of α-SMA, vimentin, collagen I, and collagen III; the expression level of lnc PVT1 expression showed to be significantly increased by TGF-β1 stimulation. The protein levels of TGF-β1, TGFBR1, and TGFBR2 were also decreased by lnc PVT1 knockdown. Under TGF-β1 stimulation, lnc PVT1 knockdown decreased FN1, α-SMA, collagen I, and collagen III protein contents, inhibited HCF cell viability and enhanced cell apoptosis, and inhibited Smad2/3 phosphorylation. Lnc PVT1 positively regulated MYC expression with or without TGF-β1 stimulation; MYC overexpression in TGF-β1-stimulated HCFs significantly attenuated the effects of lnc PVT1 knockdown on HCF proliferation and trans-differentiation to MFs. In the ISO-induced myocardial fibrosis model, lnc PVT1 knockdown partially reduced fibrotic area, improved cardiac functions, and decreased the levels of fibrotic markers. In addition, lnc PVT1 knockdown decreased MYC and CDK4 levels but increased E-cadherin in mice heart tissues. lnc PVT1 is up-regulated in cardiac fibrosis and TGF-β1-stimulated HCFs. Lnc PVT1 knockdown partially ameliorates TGF-β1-induced HCF activation and trans-differentiation into MFs in vitro and ISO-induced myocardial fibrosis in vivo, potentially through interacting with MYC and up-regulating MYC.

Long non-coding RNA PVT1 regulates atherosclerosis progression via the microRNA-106b-5p/ACSL4 axis

Long non-coding RNAs (lncRNAs) have been associated with atherosclerosis (AS), but the role of lncRNA PVT1 in this disease is still unknown. However, lncRNA PVT1 was found to be significantly upregulated in the serum of AS patients. In vitro experiments using human vascular endothelial cells (HUVECs) showed that oxidized low-density lipoprotein (ox-LDL) treatment enhanced PVT1 expression and impeded HUVEC proliferation, which could be reversed by PVT1 knockdown or miR-106b-5p mimics. Additionally, knockdown of PVT1 and overexpression of miR-106b-5p inhibited the increase of iron content, MDA level, lipid ROS, ACSL4, and PTGS2 in ox-LDL-induced HUVECs, as well as the decrease of GSH and GPX4. We also found that PVT1 knockdown reduced lipid deposition, atherosclerotic plaque number, and size in ApoE−/− mice. These results suggest that PVT1 plays a crucial role in AS progression by regulating the miR-106b-5p/ACSL4 axis in HUVECs, and may therefore be a potential therapeutic target for AS.

LncRNA PVT1 influences breast cancer cells glycolysis through sponging miR-145-5p

BackgroundLong-non-coding RNA PVT1 (lncRNA PVT1) can be used as an oncogenic regulatory non-coding RNA (ncRNA) for many cancers. However, its function and mechanism in breast cancer (BRCA) are still not clearly elucidated.ObjectiveWe attempt to explain the mechanism of PVT1’s role in breast cancer from different perspectives.MethodsWe analyzed the expression of PVT1 and its correlation with the breast cancer related clinical data in the The Cancer Genome Atlas (TCGA) database. We used PVT1 overexpression and knockdown lentivirus to infect breast cancer MDA-MB-231 cell line for cell function verification, in vitro using CCK-8 to measure proliferation, flow cytometry to measure apoptosis, transwell test to measure invasion and migration ability, detecting cell extracellular acidification rate (ECAR) to assess glycolysis metabolism and explore the biological functions of PVT1 in breast cancer cells. Transcriptome sequencing was used to analyze the changes of related genes in cells after overexpression of PVT1. In vivo we used a xenograft model to study the effect of PVT1 on breast cancer.ResultsPVT1 was up-regulated in breast cancer tissues and was positively correlated with the clinical stage of breast cancer patients. Overexpression of PVT1 in vitro promoted cell proliferation, migration and invasion, and promoted tumor growth in vivo. Knockdown of PVT1 led to the opposite biological consequence. Further bioinformatics analysis showed that PVT1 changes the glycolysis metabolism of tumors through regulation of glycolysis-related genes. In addition, the expression of miR-145-5p is negatively correlated with PVT1. We consider the possibility of PVT1 promoting cell proliferation and metastasis by regulating the aerobic glucose metabolism in breast cancer cells through sponging the miR-145-5p.ConclusionOur results reveal a potential pathway for competing endogenous RNA to regulate breast cancer glucose metabolism. PVT1 regulates glycolysis related genes expression by competitively binding to endogenous miR-145-5p in breast cancer cells to change the metabolic phenotype. This may Provide new ideas for precise molecular therapy targets for breast cancer.

Long non-coding RNA PVT1 promotes the proliferation, migration and EMT process of ovarian cancer cells by regulating CTGF.

Ovarian cancer remains one of the most common gynecological malignancies with a poor prognosis. The present study investigated the roles of long non-coding RNA plasmacytoma variant translocation 1 (lncRNA PVT1) in the regulation of the malignant phenotype of ovarian cancer cells, including cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT). SKOV3 and CAOV3 cells were transfected with small interfering RNA (siRNA) targeting lncRNA PVT1 (si-PVT1) or control siRNA and the si-PVT1 transfected cells were co-cultured with recombinant human connective tissue growth factor (rhCTGF). The proliferation, migration and invasion abilities of the cells were examined via Cell Counting Kit-8, colony formation, wound-healing and Transwell assays. The relative expression levels of lncRNA PVT1, CTGF, E-cadherin and vimentin were analyzed using reverse transfection-quantitative polymerase chain reaction, and western blotting was employed to detect the protein levels of CTGF, E-cadherin and vimentin. The expression of lncRNA PVT1 was significantly reduced in SKOV3 and CAOV3 cells following transfection with si-PVT1. In addition, the proliferation, migration and invasion abilities of SKOV3 and CAOV3 cells were repressed following lncRNA PVT1 knockdown. The knockdown of lncRNA PVT1 also reduced the expression of CTGF and vimentin, and increased the expression of E-cadherin. The changes in the proliferation, migration and invasion of the cells induced by transfection with si-PVT1 were partially attenuated in the presence of rhCTGF. Furthermore, co-culture with rhCTGF reversed the si-PVT1-induced changes in the expression of EMT-associated proteins. In conclusion, lncRNA PVT1 promotes the proliferation, migration, invasiveness and EMT process of ovarian cancer cells, and CTGF contributes to the effect of lncRNA PVT1.

LncRNA PVT1 regulates biological function of osteoarthritis cells by regulating miR-497/AKT3 axis.

Growing evidence indicates that lncRNAs are involved in the progression of several diseases, including osteoarthritis (OA). However, the role of the lncRNA PVT1 in OA is still unclear. The present study was aimed at exploring the impact of PVT1 on OA progression, along with potential underlying mechanisms. PVT1 expression levels in articular cartilage tissue of OA patients and non-OA patients were evaluated. To assess the proliferation and apoptosis of chondrocytes subject to treatment, PVT1, miR-497, and AKT3 were either knocked down or upregulated in IL-1β-induced chondrocytes. The variables detected were changes in levels of AKT3 and extracellular matrix (ECM)-related factors (including aggrecan, collagen Type II, and MMP-9). Elevated PVT1 levels were found in cartilage tissue of OA patients and IL-1β-induced chondrocytes. It was also observed that PVT1 knockdown and miR-497 upregulation led to enhanced cell proliferation and suppressed apoptosis. In addition, a decrease in aggrecan and collagen type II levels and an increase in MMP-9 levels were observed in IL-1β-induced chondrocytes. A dual luciferase reporter assay was performed to identify the factors that interacted with miR-497, PVT1, and AKT3. It was observed through rescue experiments that enhancing AKT3 expression or knocking down miR-497 could reverse the impacts of PVT1 knockdown in IL-1β-induced chondrocytes. An upregulation of PVT1 is observed in OA patients. On the other hand, PVT1 knockdown can decrease the effects of IL-1β on the proliferation, apoptosis, and expression of ECM-related proteins of chondrocytes through the regulation of the miR-497/AKT3 axis. PVT1 levels are elevated in the cartilage tissue of OA patients and IL-1β-induced chondrocytes. PVT1 knockdown alleviates the effects of IL-1β treatment on the proliferation and apoptosis of chondrocytes and ECM degradation in chondrocytes by regulating the miR-497/AKT3 axis.

Knockdown of PVT1 Exerts Neuroprotective Effects against Ischemic Stroke Injury through Regulation of miR-214/Gpx1 Axis.

Previous studies have reported that lncRNA PVT1 was closely related to ischemic stroke. Here, the role of PVT1 in ischemic stroke and the underlying mechanism were investigated. OGDR-stimulated PC12 cells were used to construct a cell model to mimic ischemic stroke. si-PVT1, miR-214 mimic, inhibitor, or the negative controls were transfected into PC12 cells prior to OGDR treatment. PVT1, miR-214, and Gpx1 expression was measured by qRT-PCR and western blotting assays. Cell proliferation and apoptosis were tested by CCK-8 assay and western blotting. The expression levels of inflammatory factors were determined by ELISA Kit. Results showed that PVT1 was increased significantly in OGDR PC12 cells. PVT1 knockdown significantly enhanced cell viability and attenuated cell apoptosis, ROS generation, and inflammation in OGDR PC12 cells. More importantly, PVT1 or Gpx1 was a target of miR-214. Mechanistically, PVT1 acted as a competing endogenous RNA of miR-214 to regulate the downstream gene Gpx1. In conclusion, PVT1 knockdown attenuated OGDR PC12 cell injury by modulating miR-214/Gpx1 axis. These findings offer a potential novel strategy for ischemic stroke therapy.

Long non‑coding RNA PVT1 regulates LPS‑induced acute kidney injury in an in vitro model of HK‑2 cells by modulating the miR‑27a‑3p/OXSR1 axis

Sepsis is a severe inflammatory disease caused by infection that can lead to multiple organ failure. Acute kidney injury (AKI) is considered to be a major cause of septic mortality in infected organs. Previous studies have revealed that non-coding RNAs are involved in AKI, but the underlying mechanisms are mostly unknown. The present study aimed to explore the role of long non-coding RNA plasmacytoma variant translocation gene 1 (lncRNA PVT1) in lipopolysaccharide (LPS)-induced acute kidney injury and the underlying mechanism. In the present study, reverse transcription-quantitative PCR analysis indicated that, in HK-2 cells treated with LPS, the mRNA expression levels of lncRNA PVT1 and oxidative stress responsive kinase 1 (OXSR1) were upregulated, and the expression of microRNA (miR)-27a-3p was downregulated. Furthermore, LPS treatment could promote the secretion of tumor necrosis factor (TNF)-α and interleukin (IL)-6, inhibit cell proliferation and induce apoptosis, which was rescued by PVT1 knockdown. Dual-luciferase reporter assay, RIP assay and pull-down assay results demonstrated that miR-27a-3p may be a target miR of PVT1, and that OXSR1 is the target gene of miR-27a-3p. Moreover, it was found that miR-27a-3p overexpression decreased the secretion of TNF-α and IL-6, promoted cell proliferation and inhibited apoptosis in LPS-treated HK-2 cells, which could be reversed by OXSR1 overexpression. Therefore, the present results indicated that lncRNA PVT1 regulated inflammatory cytokine secretion, cell proliferation and apoptosis by targeting miR-27a-3p, and modulating OXSR1 expression in LPS-induced HK-2 cells.

LncRNA-targeting bio-scaffold mediates triple immune effects for postoperative colorectal cancer immunotherapy

Colorectal cancer (CRC) recurrence after surgical resection results in poor clinical outcomes. Long noncoding RNAs (lncRNAs) are emerging new targets for mediating tumorigenesis and immunosuppression within tumor microenvironment. We develop a bio-scaffold encapsulating lncRNA-targeting biomimetic nanosystems for mediating triple immune effects against postoperative CRC recurrence. Liposome (termed as “D”)-decorated CRC cells’ membrane (CM) envelops a plasmid encoding a short hair-pinned RNA (shRNA) against plasmacytoma variant translocation 1 (Pvt1), forming the shPvt1-CM-D nanosystem. This nanosystem and the chemodrug Oxaliplatin (Oxa) are embedded in a hyaluronic acid and alginate-based bio-scaffold for postoperative implantation. (1) ShPvt1-CM-D-mediated Pvt1 knockdown strengthens Oxa-induced immunogenic cell death (ICD). (2) Such tumor antigens released from enhanced ICD and the CM from shPvt1-CM-D act as dual vaccines of dendritic cells. (3) Pvt1 knockdown by shPvt1-CM-D within granulocytic myeloid-derived suppressor cells (G-MDSCs) ameliorates G-MDSC-mediated immunosuppression. The nanosystem-carrying bio-scaffold significantly suppresses perioperative CRC local recurrence by 97.8% with survival rate (SR) of 62.5%. The bio-scaffold generates robust immune memory responses for completely suppressing tumor ectopic rechallenging and metachronous metastasis (SR: 100%). Additionally, the bio-scaffold reduces synchronously distant metastasis by 70.8%. This work presents a potent nanotechnology-facilitated lncRNA-targeting immunotherapy for postoperative CRC treatments.

CREB1 transcription-activated lncRNA PVT1 promotes cardiac fibrosis via miR-145/HCN1 axis

BackgroundCardiac fibrosis is a common pathological process of most cardiac diseases, which may result in cardiac function impairment. Long noncoding RNAs (lncRNAs) have been verified as crucial regulators of cardiac fibrosis. This study explored the function and molecular mechanism of PVT1 in cardiac fibrosis. MethodsTGF-β1-exposed human cardiac fibroblasts (HCF-a) and isoproterenol (ISO)-treated mice were used as the in vitro and in vivo cardiac fibrosis models. PVT1, miR-145, and HCN1 expression was determined by quantitative RT-PCR. Cell proliferation was evaluated by CCK-8 and EdU fluorescence staining. α-SMA and collagen I expression was assessed by immunohistochemical staining and immunofluorescence staining. Protein levels of fibrosis-related factors were assessed by Western blotting. The interaction between miR-145 and PVT1/HCN1 was evaluated by dual luciferase assay. ChIP assay was used to validate the binding of CREB1 to the promoter of PVT1. Cardiac fibrosis in mice was observed by H&E and Masson's trichrome staining. ResultsPVT1 and HCN1 were up-regulated, while miR-145 was down-regulated in the cardiac fibrosis models. PVT1 knockdown restrained TGF-β1-induced proliferation and activation of HCF-a cells. CREB1 bound to the promoter of PVT1 and activated its transcription. Mechanistically, PVT1 enhanced HCN1 expression via sponging miR-145. Finally, silencing of PVT1 attenuated cardiac fibrosis via regulating miR-145/HCN1 axis in mice in vivo. ConclusionPVT1 contributed to cardiac fibrosis by increasing HCN1 expression via sponging miR-145, which suggested that targeting PVT1 may be a therapeutic option for cardiac fibrosis and cardiac diseases.

Knockdown of long non-coding RNA plasmacytoma variant translocation 1 relieves ox-LDL-induced endothelial cell injury through regulating microRNA-30c-5p in atherosclerosis

ABSTRACT Atherosclerosis (AS) is a chronic inflammatory disease involving endothelial dysfunction, and is one of the main causes of death from cardiovascular disease (CVD). Long non-coding RNA plasmacytoma variant translocation 1 (lncRNA PVT1) is overexpressed in the serum of CVD patients. However, the mechanism by which lncRNA PVT1 functions in AS remains unknown. Our research was designed to probe interactions involving lncRNA PVT1 and oxidized low-density lipoprotein (ox-LDL)-stimulated endothelial cell injury in AS. lncRNA PVT1 expression in the serum of AS patients and ox-LDL-stimulated human umbilical vein endothelial cells (HUVECs) was detected using reverse transcriptase quantitative polymerase chain reaction (RT-qPCR). Cell counting kit (CCK)-8 assays, flow cytometry (FCM), and enzyme-linked immunosorbent assay (ELISA) were used to determine cell proliferation, apoptosis, and levels of inflammatory cytokines, respectively. Moreover, the correlation between lncRNA PVT1 and miR-30 c-5p was predicted and verified using StarBase3.0, TargetScan, and luciferase reporter-gene assays. lncRNA PVT1 was overexpressed in the serum of AS patients and in ox-LDL-stimulated HUVECs relative to controls. Knockdown of lncRNA PVT1 facilitated proliferation, reduced apoptosis, and secretion of inflammatory factors in ox-LDL-treated HUVECs. Moreover, miR-30 c-5p was verified as a direct target of lncRNA PVT1. Furthermore, we observed that miR-30 c-5p expression was lower in AS patients than in controls. In addition, the influence of lncRNA PVT1 knockdown on ox-LDL-treated HUVECs was significantly reversed by downregulation of miR-30 c-5p. In conclusion, lncRNA PVT1 silencing inhibited HUVEC damage stimulated by ox-LDL via miR-30 c-5p regulation.

LncRNA PVT1 Promotes Hypoxia-Induced Cardiomyocyte Injury by Inhibiting miR-214-3p.

Objective To explore the effect and related mechanism of LncRNA PVT1 on hypoxia-induced cardiomyocyte injury. Methods PVT1RNA and miR-214-3p levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell vitality and apoptosis were, respectively, evaluated by Cell Counting Kit-8 (CCK-8) and flow cytometry analysis. Starbase and Dual luciferase reporter (DLR) gene assay was employed to validate the interaction between miR-214-3p and PVT1. Results PVT1 was statistically upregulated, and miR-214-3p was statistically downregulated in hypoxia-induced H9c2 cells. The survival rate of H9c2 cells induced by hypoxia decreased statistically, while the apoptosis rate increased statistically (P < 0.05). PVT1 knockdown upregulated the hypoxia-induced H9c2 cell viability and inhibited apoptosis. DLR assay verified the targeting relationship between PVT1 and miR-214-3p. In addition, miR-214-3p inhibitors reversed the viability of H9c2 cells with PVT1 knockout and promoted apoptosis. Conclusion Silencing PVT1 can enhance the hypoxia-induced H9c2 cell viability and inhibit apoptosis, providing a potential target for the treatment of cardiovascular diseases.

LncRNA PVT1 Knockdown Ameliorates Myocardial Ischemia Reperfusion Damage via Suppressing Gasdermin D-Mediated Pyroptosis in Cardiomyocytes.

Objective: Myocardial ischemia reperfusion (I/R) damage is a life-threatening vascular emergency after myocardial infarction. Here, we observed the cardioprotective effect of long non-coding RNA (lncRNA) PVT1 knockdown against myocardial I/R damage.Methods: This study constructed a myocardial I/R-induced mouse model and a hypoxia/reoxygenation (H/R)-treated H9C2 cells. PVT1 expression was examined via RT-qPCR. After silencing PVT1 via shRNA against PVT1, H&E, and Masson staining was performed to observe myocardial I/R damage. Indicators of myocardial injury including cTnI, LDH, BNP, and CK-MB were examined by ELISA. Inflammatory factors (TNF-α, IL-1β, and IL-6), Gasdermin D (GSDMD), and Caspase1 were detected via RT-qPCR, western blot, immunohistochemistry, or immunofluorescence. Furthermore, CCK-8 and flow cytometry were presented for detecting cell viability and apoptosis.Results: LncRNA PVT1 was markedly up-regulated in myocardial I/R tissue specimens as well as H/R-induced H9C2 cells. Silencing PVT1 significantly lowered serum levels of cTnI, LDH, BNP, and CK-MB in myocardial I/R mice. H&E and Masson staining showed that silencing PVT1 alleviated myocardial I/R injury. PVT1 knockdown significantly lowered the production and release of inflammatory factors as well as inhibited the expression of GSDMD-N and Caspase1 in myocardial I/R tissue specimens as well as H/R-induced H9C2 cells. Moreover, silencing PVT1 facilitated cell viability and induced apoptosis of H/R-treated H9C2 cells.Conclusion: Our findings demonstrated that silencing PVT1 could alleviate myocardial I/R damage through suppressing GSDMD-mediated pyroptosis in vivo and in vitro. Thus, PVT1 knockdown may offer an alternative therapeutic strategy against myocardial I/R damage.

Long non-coding RNA Pvt1 modulates the pathological cardiac hypertrophy via miR-196b-mediated OSMR regulation

Cardiac hypertrophy is the uppermost risk factor for the development of heart failure, leading to irreversible cardiac structural remodeling and sudden death. As a major mediator of cardiac remodeling, oncostatin M (OSM) and its receptor, OSMR, attract plenty of interest. Recent studies have demonstrated key effects of noncoding RNAs on myocardial remodeling. However, whether noncoding RNAs that regulate the expression of OSMR would regulate the process of remodeling remain unclear. Herein, we observed that long noncoding RNA (lncRNA) Pvt1 expression showed to be significantly elicited by aortic banding (AB) operation in vivo and by angiotensin (Ang II) treatment in vitro. Pvt1 knockdown significantly attenuated the myocardial hypertrophy caused by pressure overload within rats and the cardiac myocyte hypertrophy caused by Ang II in vitro. Moreover, Pvt1 knockdown also decreased cellular myomesin and B-raf, which was involved in OSM function in cardiac remodeling. Based on online tools prediction, miR-196b may simultaneously target Pvt1 and OSMR 3′ untranslated region (UTR). In rat H9c2 cells and primary cardiac myocyte, Pvt1 and miR-196b exerted negative regulatory effects on each other and miR-196b negatively regulated OSMR expression. Pvt1 directly targeted miR-196b to relieve miR-196b-induced OSMR suppression via acting as a competing endogenous RNA (ceRNA). Moreover, the effect of miR-196b suppression upon the B-raf was opposite to Pvt1 knockdown, and miR-196b suppression might significantly attenuate the effect of Pvt1 knockdown. In summary, Pvt1/miR-196b axis modulating cardiomyocyte hypertrophy and remodeling via OSMR. Our findings provide a rationale for further studies on the potential therapeutic benefits of Pvt1 function and mechanism in cardiac and cardiomyocyte hypertrophy by a lncRNA-miRNA-mRNA network.

Long Noncoding RNA PVT1 and MYC Are Co-Regulated By Bromodomain Protein BRD4 in Multiple Myeloma and Associated with Disease Progression

Background: Special region called superenhancer where Bromodomain-containing protein 4 (BRD4) complex densely accumulates attracts attention. MYC is a transcription factor highly expressing in many types of cancer and plays an important role on carcinogenesis. MYC possesses superenhancer and its expression is inhibited by BRD4 inhibitor JQ1. Recent transcriptome-wide analyses have revealed an overwhelming amount of transcribed but not translated non-coding RNAs capable of influencing diverse cellular processes such as proliferation, apoptosis, and motility. Long non-coding RNA (lnc RNAs), which are commonly defined as transcripts >200 nt in length, have emerged as a class of key regulatory RNA. LncRNAs are deregulated in diverse human cancers and associated with disease progression; however little is available in multiple myeloma (MM). LncRNA PVT1 locates adjacent to MYC is also reported to be associated with carcinogenesis and abnormal PVT1 fusing NBEA or WWOX in MM with 8q24 abnormality has been reported, but its roles and regulation machinery remain uncertain.Methods: 140 of MM patients, 58 of MGUS patients, 6 of control BM are subjected to the study after obtaining informed consent. The study was approved by IRB following Declaration of Helsinki. PVT1 and MYC expression were determined by RQ-PCR in RNA was extracted from purified CD138+ plasma cells from bone marrow (BM) mononuclear cells. Whole transcriptome analysis by next generation sequencer (NGS) using Illumina NextSeq 500 was performed in part of the samples. MM cell lines KMS11, KMS12PE, OPM2, RPMI8226 were treated with bromodomain BRD4 inhibitor JQ1, CPI203 or MYC inhibitor 10058-F4, then growth rate and MYC/PVT1 expression was analyzed by RQ-PCR and NGS. To analyze the function and role of PVT1, siRNA for PVT1 was transfected to the cell lines. MYC protein expression was determined by western blot.Results: The expression level of PVT1 and MYC were significantly higher in MM (mean for PVT1 2.58, MYC 0.74) than MGUS (mean for PVT1 0.88, MYC 0.06) and control (mean for PVT1 0.06, MYC 0.07) (p<0.001, p<0.001). NGS confirmed that PVT1 was an gene expressed higher in MM than in MGUS. PVT1 and MYC expressions in MM did not differ in between different karyotypes (p=0.79 and 0.5) and stages according to ISS (p=0.21 and 0.95).No correlation between PVT1 expression level and poor cytogenetics. Interestingly the levels of PVT1 and MYC was positively correlated (r=0.423, p<0.0001 in control, MGUS and MM, r=0.484, p<0.001 in MM only). PVT1 expression was also significantly correlated with BMI1 and EZH2 (r=.0.63, p<0.001 and r=0.65, p<0.001). BRD4 inhibitor JQ1 and CPI203 inhibited cell proliferation of MM cell lines KMS11, KMS12PE, OPM2 and RPMI8226. JO1 and CPI203 almost completely shut down both PVT1 expression in KMS11, KMS12PE, OPM2 except in RPMI8226. RNA sequencing by NGS confirmed that PVT1 was one of the genes significantly downregulated by BRD4 blockade. MYC expression also diminished in the cell lines except RPMI8226 in both transcripts and protein level by JQ1. In contrast, both MYC siRNA and MYC inhibitor 10054-F4 which inhibits MYC transcriptional activity by disrupting MYC-MAX complex did not change PVT1 expression level at all. PVT1 knockdown by siRNA showed no appreciable phenotypic change so far. Interetingly overall survival of the MM patients with higher PVT1 expression tended to be shorter with median 2.7 years compared to 5.0 years (p=0.09).Conclusions: Positive correlation between MYC and PVT1 in patients, synchronous downregulation of MYC and PVT1 by JQ1 and CPI203, no effect of MYC inhibitor for PVT1 expression suggest that these two genes expressions are co-regulated by BRD4 complex.Association between higher PVT1 expression and MM, poor prognosis suggests its pathogenetic role. PVT1 is known to stabilize MYC protein by inhibiting Th58 phosphorylation, and to enhance MYC transcription by binding to the promoter. Thus, PVT1 and MYC may cooperately contribute to MM pathogenesis and progression, and our discovery may support the rationale targeting BRD4. DisclosuresMurakami:Ono: Honoraria; BMS: Honoraria; Fujimoto: Honoraria; Sanofi: Honoraria; Takeda: Honoraria; Celgene: Honoraria.

LncRNA PVT1 accelerates LPS-induced septic acute kidney injury through targeting miR-17-5p and regulating NF-κB pathway.

Long noncoding RNA PVT1 is associated with diverse human diseases, including acute kidney injury (AKI). However, our understandings of PVT1 on septic AKI are limited. The septic AKI model was constructed through lipopolysaccharide (LPS) treatment. PVT1 and miR-17-5p levels were measured using qRT-PCR analysis. The concentrations of inflammatory cytokines were determined with ELISA kits. Cell viability and apoptosis were assessed using CCK-8 assay and flow-cytometric analysis, respectively. Protein levels were examined using western blot assay. The targeting association between miR-17-5p and PVT1 was verified by dual-luciferase reporter, RIP and RNA pull-down assays. PVT1 level was elevated and miR-17-5p level was declined in septic AKI patients' serum and LPS-stimulated HK-2 cells. Cell viability was suppressed and cell apoptosis and inflammation were promoted after LPS treatment. PVT1 knockdown or miR-17-5p elevation restored LPS-mediated HK-2 cell injury. MiR-17-5p was sponged by PVT1, and its inhibition weakened the impact of PVT1 deficiency on LPS-mediated injury of HK-2 cells. In addition, PVT1 knockdown inactivated NF-κB pathway mediated by LPS treatment, but miR-17-5p inhibition further reversed this effect. PVT1 knockdown promoted cell viability, suppressed inflammatory response and apoptosis by regulating miR-17-5p expression and NF-κB pathway in LPS-stimulated HK-2 cells.

PVT1 knockdown inhibited the biological behavior of LPS-induced cardiac fibroblasts by regulating miR-24.

The heart is one of the target organs vulnerable to sepsis. About 50% of sepsis patients will suffer from myocardial injury and cardiac dysfunction, which will aggravate the sepsis and affect its prognosis. Here, we attempt to investigate the function of long non coding RNA PVT1 in LPS-induced cardiac fibroblasts in vitro, and explore its potential mechanism. The expression of PVT1 in LPS-induced cardiac fibroblasts was detected by qRT-PCR. CCK-8 assay, cell migration, qRT-PCR and western blotting analysis were applied to evaluating the effect of PVT1 knockdown on LPS-induced cardiac fibroblasts. The bioinformatics analysis and the rescue experiment were devoted to the underlying mechanism. PVT1 expression was up-regulated in LPS-induced cardiac fibroblasts. And knockdown of PVT1 inhibited cell viability and migration, alleviated inflammation cytokines production of LPS-treated cardiac fibroblasts. The bioinformatics analysis predicted PVT1 negatively regulates miR-24 and KLF6 is a direct target of miR-24. In a word, we observed PVT1 expression level was up-regulated in LPS- treated cardiac fibroblasts. PVT1 knockdown could alleviate LPS-induced biological behavior of cardiac fibroblasts through sponging miR-24 in vitro.

Knockdown of lncRNA PVT1 attenuated macrophage M1 polarization and relieved sepsis induced myocardial injury via miR-29a/HMGB1 axis

BackgroundLncRNA PVT1 was reported to be elevated in septic myocardial tissue. The underlying mechanism by which PVT1 aggravated sepsis induced myocardial injury needs further investigation. MethodsMice was subjected to LPS injection to mimic in vivo sepsis model. HE staining was applied to observe tissue injury. Cardiac function of mice was determined by echocardiography. Bone marrow derived macrophage (BMDM) was used to confirm the regulatory effect of PVT1 in macrophage polarization. Western blotting or qRT-PCR were performed to evaluate protein or mRNA levels, respectively. ELISA was conducted to determine cytokine levels. Interaction between PVT1 and miR-29a, miR-29a and HMGB1 were accessed by dual luciferase assay. ResultsExpression of PVT1 was elevated in myocardial tissue and heart infiltrating macrophages of sepsis mice. PVT1 knockdown alleviated LPS induced myocardial injury and attenuated M1 macrophage polarization. The mechanic study suggested that PVT1 targeted miR-29a, thus elevated expression of HMGB1, which was repressed by miR-29a targeting. The effect of PVT1 on M1 macrophage polarization was dependent on targeting miR-29a. ConclusionPVT1 promoted M1 polarization and aggravated LPS induced myocardial injury via miR-29a/HMGB1 axis.

The lncRNA PVT1/miR-590-5p/FSTL1 axis modulates the proliferation and migration of airway smooth muscle cells in asthma

Objective Asthma is a prevalent chronic inflammatory airway disease that is characterised by airway remodelling and airway hyperresponsiveness. Abnormal proliferation and migration of airway smooth muscle cells (ASMCs) contribute to airway remodelling in asthma. However, the molecular mechanism underlying an increased ASMC mass in asthma remains elusive. Herein, we aimed at investigating the regulation of lncRNA PVT1 on ASMCs and focussing on the mechanism in the proliferation and migration. Methods Expression levels of lncRNA PVT1 and miR-590-5p in the serum collected from 24 children with asthma and 10 control children were determined by qRT-PCR. ASMCs proliferation and migration prior to and post platelet-derived growth factor subunit B (PDGF-BB) stimulation were examined by CCK-8 test and transwell assay. Dual-luciferase reporter assay was performed to determine miR-590-5p interaction with lncRNA PVT1 and follistatin-like 1 (FSTL1). Expression of lncRNA PVT1, miR-590-5p, FSTL1, C-Myc, cyclin D1, and cyclin-dependent kinase 1 (CDK1) was tested by quantitative real-time PCR (qRT-PCR) and immunoblotting analysis. Results The expression level of lncRNA PVT1 was higher but the expression level of miR-590-5p was lower in the serum of children with asthma than in control children. The expression level of lncRNA PVT1 was negatively correlated with the expression level of miR-590-5p in asthma. LncRNA PVT1 was upregulated upon PDGF-BB stimulation. LncRNA PVT1 knockdown by its specific shRNA repressed PDGF-BB-induced promotion of proliferation and migration in ASMCs and triggered an elevated miR-590-5p along with declined C-Myc, cyclin D1, and CDK1. The effects of lncRNA PVT1 knockdown on PDGF-BB-induced ASMCs were lost upon miR-590-5p inhibition. MiR-590-5p targeted FSTL1 gene and declined its expression, thus suppressing ASMC proliferation and migration following PDGF-BB stimulation and downregulating C-Myc, cyclin D1, and CDK1 expressions. The effects of miR-590-5p on PDGF-BB-induced ASMCs were lost upon FSTL1 overexpression. Conclusion These results support the notion that the lncRNA PVT1/miR-590-5p/FSTL1 axis modulates ASMCs proliferation and migration following PDGF-BB stimulation, providing a potential therapeutic target to attenuate airway remodelling in asthma.