LncRNA KCNQ1OT1靶向调控miR-124-3p/HMGB1轴对高糖诱导肾小球系膜细胞增殖、凋亡及纤维化的影响

摘要 目的：探讨长链非编码核糖核酸（LncRNA）KCNQ1OT1靶向调控miR-124-3p/高迁移率族蛋白B1（HMGB1）轴对高糖诱导肾小球系膜细胞（HMC）增殖、凋亡及纤维化的影响。方法：将人HMC分为对照组（NC组）、高糖组（30 mmol/L葡萄糖）、阴性序列（si-NC）组、KCNQ1OT1小干扰核糖核酸（RNA）（si-KCNQ1OT1）组、si-KCNQ1OT1+模拟对照序列（miR-NC）组、si-KCNQ1OT1+miR-124-3p抑制剂（miR-124-3p inhibitor）组,各组在转染后进行高糖处理。实时荧光定量聚合酶链式反应（RT-qPCR）检测LncRNA KCNQ1OT1信使核糖核酸（mRNA）、miR-124-3p mRNA、HMGB1 mRNA表达;四甲基偶氮唑盐比色法（MTT）检测细胞增殖活性;流式细胞术检测细胞凋亡率;蛋白印迹法（Western blot）检测HMGB1蛋白、增殖相关蛋白[细胞周期蛋白1（CyclinD1）]、细胞凋亡蛋白[半胱氨酸蛋白酶-3（caspase-3）、半胱氨酸蛋白酶蛋白9（caspase-9）]、细胞纤维化蛋白[纤维连接蛋白（FN）、细胞黏附分子-1（ICAM-1）]表达;双荧光素酶报告基因实验验证LncRNA KCNQ1OT1与miR-124-3p与HMGB1之间的靶向关系。结果：与NC组比较,高糖组KCNQ1OT1 mRNA、HMGB1 mRNA及HMGB1蛋白、CyclinD1蛋白、FN蛋白、ICAM-1蛋白表达、HMC活性（24 h、48 h和72 h）明显上升,miR-124-3p mRNA、caspase-3蛋白及caspase-9蛋白表达、HMC凋亡率明显下降（P<0.05）;与高糖组、si-NC组比较,si-KCNQ1OT1组KCNQ1OT1 mRNA、HMGB1 mRNA及HMGB1蛋白、CyclinD1蛋白、FN蛋白、ICAM-1蛋白表达、HMC活性（24 h、48 h和72 h）明显下降,miR-124-3p mRNA、caspase-3蛋白及caspase-9蛋白表达、HMC凋亡率明显上升（P<0.05）;与si-KCNQ1OT1组、si-KCNQ1OT1+miR-NC组比较,si-KCNQ1OT1+miR-124-3p inhibitor组HMGB1 mRNA及HMGB1蛋白、CyclinD1蛋白、FN蛋白、ICAM-1蛋白表达、HMC活性（24 h、48 h和72 h）明显上升,miR-124-3p mRNA、caspase-3蛋白及caspase-9蛋白表达、HMC凋亡率明显下降（P<0.05）。较miR-NC组与KCNQ1OT1-WT共转染组而言,miR-124-3p mimic组与KCNQ1OT1-WT共转染组细胞荧光素酶活性明显降低（P<0.05）;较miR-NC组与HMGB1-WT共转染组而言,miR-124-3p mimic组与HMGB1-WT共转染组细胞荧光素酶活性明显降低（P<0.05）。结论：LncRNA KCNQ1OT1可以靶向下调miR-124-3p mRNA表达,上调HMGB1 mRNA及HMGB1蛋白表达,促进高糖诱导HMC增殖,抑制凋亡,促进细胞纤维化发展。     

LncRNA MAGI2-AS3 inhibits hepatocellular carcinoma cell proliferation and migration by targeting the miR-374b-5p/SMG1 signaling pathway

Long noncoding RNAs (lncRNAs) have been proven to play critical roles in cancer progression. Recently, lncRNA MAGI2-AS3 has been revealed to be a tumor suppressor and inhibit cell growth by targeting the Fas/FasL signalling pathway in breast cancer. However, the role and underlying mechanism of MAGI2-AS3 in hepatocellular carcinoma (HCC) remain largely unknown. In the current study, we found that MAGI2-AS3 expression is downregulated in HCC tissues and closely associated with some clinical characteristics (tumor size, lymph node metastasis, and TNM stage) and poor overall survival. Overexpression of MAGI2-AS3 inhibits HCC cell proliferation and migration in vitro, while impedes tumor growth in vivo accordantly. In addition, our data suggest that MAGI2-AS3 could function as an endogenous sponge of miR-374b-5p by directly binding to it and suppressing its expression. Furthermore, miR-374b-5p upregulation could restore the inhibitory effect of MAGI2-AS3 on HCC cells processes. Moreover, suppressor with morphogenetic effect on genitalia family member 1 (SMG1) is positively regulated by MAGI2-AS3 via absorbing miR-374b-5p in HCC cells. More important, SMG1 knockdown reverses the suppressive function of MAGI2-AS3 in HCC cell processes. Taken together, we reveal a functional MAGI2-AS3/miR-374b-5p/SMG1 axis that suppresses HCC progression, potently suggesting a new road for HCC treatment.     

Hydrogen sulfide protects against acetaminophen-induced acute liver injury by inhibiting apoptosis via the JNK/MAPK signaling pathway

Acetaminophen (APAP) is a widely used over-the-counter analgesic and antipyretic. It can cause hepatotoxicity. Recent studies demonstrated that hydrogen sulfide (H₂S) exhibits cell protection in several cell types. This study was designed to investigate whether H ₂S ameliorated APAP-induced acute liver injury and to elucidate its mechanisms. In this study, we analyzed the detailed biological and molecular processes of APAP-induced hepatotoxicity using a bioinformatics analysis, which showed that apoptosis and the c-Jun N-terminal kinase (JNK)/mitogen-activated protein kinase pathway were confirmed to play critical roles in these processes. We further investigated the protective effects of H ₂S on APAP-induced hepatotoxicity. In vivo, we observed that the exogenous supplement of H ₂S ameliorated APAP-induced liver injury. Cystathionine-β-synthase (CBS) and cystathionine-γ-lyase (CSE) systems were the endogenous pathway of H ₂S. The expression of CBS/CSE was decreased in APAP-treated mice, while H ₂S could significantly restore it. In addition, APAP-induced JNK activation was inhibited by H ₂S in vivo. In vitro, H ₂S abolished the active effects of APAP on caspase3, Bax, and Bcl-2 expressions as well as JNK phosphorylation in hepatocytes. It was found through flow cytometry that the amount of APAP-induced apoptotic hepatocytes was decreased in the presence of H ₂S. In conclusion, our results suggested that H ₂S attenuated APAP-induced apoptosis in hepatocytes through JNK/MAPK siganaling pathway.     

miR-376a inhibits glioma proliferation and angiogenesis by regulating YAP1/VEGF signalling via targeting of SIRT1

BackgroundGlioma is the most common cancer in the central nervous system. Previous studies have revealed that the miR-376 family is crucial in tumour development; however, its detailed mechanism in glioma is not clear.MethodsCellular mRNA or protein levels of miR-376a, SIRT1, VEGF and YAP1 were detected via qRT–PCR or Western blotting. We analysed the proliferation, angiogenesis and migration abilities of glioma cell lines using colony formation, tube formation and Transwell assays. A luciferase assay was performed to determine whether miR-376a could recognize SIRT1 mRNA. Xenograft experiments were performed to analyse the tumorigenesis capacity of glioma cell lines in nude mice. The angiogenesis marker CD31 in xenograft tumours was detected via immunohistochemistry (IHC).ResultsmiR-376a expression was lower in glioma cells than in normal astrocytes. miR-376a mimic inhibited SIRT1, YAP1, and VEGF expression and suppressed the proliferation, migration and angiogenesis abilities of the glioma cell lines LN229 and A172, whereas miR-376a inhibitor exerted the opposite functions. In a luciferase assay, miR-376a inhibited the luciferase activity of WT-SIRT1. SIRT1 overexpression upregulated YAP1 and VEGF in glioma cells and promoted proliferation, migration and angiogenesis. Xenografts with ectopic miR-376a expression exhibited lower volumes and weights and a slower growth curve. Overexpression of miR-376a inhibited YAP1/VEGF signalling and angiogenesis by inhibiting SIRT1 in xenograft tissues.ConclusionmiR-376a directly targets and inhibits SIRT1 in glioma cells. Downregulation of SIRT1 resulted in decreased YAP1 and VEGF signalling, which led to suppression of glioma cell proliferation, migration and angiogenesis.     

LncRNA LEF1-AS1 regulates the migration and proliferation of vascular smooth muscle cells by targeting miR-544a/PTEN axis

Long noncoding RNAs (lncRNAs) play important roles in endothelium development. A lncRNA, LEF1-AS1, is recently emerging as a potent mediator of the proliferation and migration of a number of cells, including smooth muscle cells. However, the effects of LEF1-AS1 in atherosclerosis remains largely unknown. Specimens from patients with coronary artery atherosclerosis were collected. The quantitative real-time polymerase chain reaction was used to analyze levels of LEF1-AS1 and microRNA-544a (miR-544a). Western blot analysis was used to assess PTEN, P-Akt, and T-Akt protein expression. Proliferation, migration, and invasion of cells were analyzed by cell counting kit-8 assay, scratch wound assay, and transwell assay, respectively. The interaction between LEF1-AS1, miR-544a, and PTEN was probed using bioinformatical analysis and dual-luciferase assay. In plasma and tissue of patients with coronary artery atherosclerosis, LEF1-AS1 was upregulated and miR-544a was downregulated. A negative correlation was found between LEF1-AS1 and miR-544a. miR-544a overexpression reversed the inhibition of LEF1-AS1 in smooth muscle cell proliferation and invasion, which were mediated through the PTEN pathway. LEF1-AS1 regulates smooth muscle cell proliferation and migration through the miR-544a/PTEN axis, indicating that LEF1-AS1 may be a potential therapeutic target in atherosclerosis.     

MicroRNA-221 regulates osteosarcoma cell proliferation,apoptosis, migration,and invasion by targeting CDKN1B/p27

MicroRNAs (miRNAs, miR) are of critical importance in growth and metastasis of cancer cells; however, the underlying functions of miRNAs in osteosarcoma (OS) remain largely unknown. This study was aimed to elucidate the role of miR-221 in regulating the biological behavior of OS cells. The proliferation ability was examined by cell counting kit-8 (CCK-8) and cell cycle assay. The abilities of cell migration, invasion, and apoptosis were monitored by transwell assay and flow cytometry, respectively. The effect of miR-221 on cyclin-dependent kinase inhibitor 1B (CDKN1B) expression was evaluated by luciferase assays, real-time polymerase chain reaction, and Western blot analysis. We found that miR-221 was elevated in OS cell lines compared with the normal osteoblastic cell line. Transfection of the miR-221 inhibitor into MG63 and U-2OS cell lines obviously suppressed cell proliferation, migration, and invasion, which is accompanied with cell cycle arrest in G0/G1 phase. Furthermore, luciferase reporter assays indicated that CDKN1B is directly targeted by miR-221 in OS cells. Knockdown of CDKN1B inhibited the effects of miR-221 inhibitor, along with decreased Bax and caspase-3 and increased cyclin E, cyclin D1, Bcl-2, Snail, and Twist1 expression. The results suggested that miR-221 might act as a potentially useful target for treatment of OS.     

SKP2, positively regulated by circ_ODC1/miR-422a axis,promotes the proliferation of retinoblastoma

Retinoblastoma (RB) is the most common intraocular malignancy in infants and children. S-phase kinase-associated protein 2 (SKP2) has been unmasked as an oncogene in a great many of carcinomas. The biologic function and the detailed molecular mechanism of SKP2 in RB need to be better understood. In this study, real-time quantitative polymerase chain reaction and Western blot showed the ectopic expression of SKP2 in RB tissues and cell lines. Loss of function assays showed the attenuated cell proliferation in RB as a result of SKP2 knockdown. In addition, bioinformatics analysis predicted the interaction between SKP2 and miR-422a. Luciferase reporter assay and Pearson's correlation analysis validated the negative correlation between miR-422a and SKP2. MiR-422a overexpression led to a decline of SKP2 expression and cell growth in RB. The binding capacity between miR-422a and circ_ODC1 was also predicted by bioinformatics analysis. Pearson's correlation analysis and luciferase reporter assay confirmed that circ_ODC1 is negatively correlated with miR-422a. Silencing circ_ODC1 resulted in a rise in miR-422a expression and RB cell growth. Moreover, reduced cell growth was restored by SKP2 overexpression. In a word, SKP2, induced by circ_ODC1 and miR-422a, promotes RB proliferation. Our new findings in this research might expedite the discovery of novel prognostic markers and therapeutic targets of RB.     

Licochalcone A attenuates abdominal aortic aneurysm induced by angiotensin II via regulating the miR-181b/SIRT1/HO-1 signaling

Licochalcone A (LA), a chalcone derived from liquorice, exhibits multiple biological activities, including anti-oxidation and anti-inflammation. This study aimed to investigate the role and underlying mechanism of LA in the abdominal aortic aneurysm (AAA). AAA model was established by continuous infusion of 1000 ng/kg/min of angiotensin II (AngII) in ApoE ^-/- mice for 4 weeks. At 7 days before AngII administration, 5 mg/kg/day or 10 mg/kg/day of LA was intraperitoneally administered to mice and continued for 4 weeks. The characteristics and quantification of AAAs were determined in situ. Real-time PCR or western blot was used to measure mRNA or protein levels of matrix metalloproteinase 2 and matrix metalloproteinase 9; pro-inflammatory cytokines tumor necrosis factor-α, interleukin-1β, and interleukin-6; apoptosis-related proteins Bax, Bcl-2, and active caspase-3; miR-181b; Sirtuin 1 (SIRT1); and heme oxygenase-1 (HO-1). Mouse-aorta-origin vascular smooth muscle (MOVAS) cells were used to confirm the involved pathways in vitro. We found LA administration dose-dependently reduced the incidence of AngII-induced AAA, aneurysm diameter enlargement, elastin degradation, matrix metalloproteinase production, pro-inflammatory cytokines and miR-181b expression, and vascular smooth muscle cell apoptosis. It elevated SIRT1 and HO-1 expression that was suppressed by AngII. AngII enhanced miR-181b but reduced SIRT1 and HO-1 expression in MOVAS cells. In AngII-stimulated MOVAS cells, downregulation of miR-181b significantly upregulated the expression of SIRT1 and HO-1, the effect of which was abrogated by SIRT1 siRNA. Collectively, LA could attenuate AngII-induced AAA by modulating the miR-181b/SIRT1/HO-1 signaling. LA might be a potential medical therapy for small AAA.     

CircTHBS1 targeting miR-211/CCND2 pathway to promote cell proliferation and migration potential in primary cystitis glandularis cells

The pathogenesis of cystitis glandular (CG) is unclear, but it is generally considered to be a neoplastic lesion of urothelial hyperplasia formed by long-term chronic stimulation. There is growing evidence that circRNAs play important roles in a variety of cellular processes. However, there are few reports on the role and molecular mechanism of circRNA in CG. In the present study, we first isolated primary cells from CG tissues and adjacent normal tissues. Further experiments showed that CircTHBS1 was up-regulated in primary CG cells (pCGs). The results of CCK-8 showed that the overexpression of CircTHBS1 promoted the viability of pCGs, while the deletion of CircTHBS1 reduced the cell viability. Knocking out CircTHBS1 also inhibited the migration of pCGs. In addition, we demonstrated that CircTHBS1 played a role in the adsorption of miR-211 by “sponge” in pCG. In turn, miR-211 can directly target CYCLIN D2 (CCND2) 3′UTR to perform its function. Finally, we confirmed the role and mechanism of CircTHBS1/miR-211/CCND2 regulation axis in pCGs. In summary, our study is the first to reveal the role and underlying mechanism of CircTHBS1 in CG, providing a potential biomarker and therapeutic target for human CG.