KCNQ1OT1 facilitates progression of non-small-cell lung carcinoma via modulating miRNA-27b-3p/HSP90AA1 axis

Long noncoding RNA KCNQ1OT1 participates in the regulation of imprinted genes within the kcnq1 domain. But its roles in carcinogenesis and metastasis remain largely elusive. Herein, we evaluated its potential in non-small-cell lung cancer (NSCLC) progression. We demonstrated that the KCNQ1OT1 level was upregulated in NSCLC tissues and cell lines. High KCNQ1OT1 level correlated with poor overall and progression-free survival in NSCLC patients. KCNQ1OT1 facilitated proliferation, migration, and invasion in H460 cells. Furthermore, knockdown of KCNQ1OT1 reduced the expression of HSP90AA1. KCNQ1OT1 presented a positive correlation with HSP90AA1 which predicted the tumor progression in NSCLC from The Cancer Genome Atlas database. Intriguingly, KCNQ1OT1 modulated HSP90AA1 expression by sponging miR-27b-3p. MiR-27b-3p counteracted the effect of KCNQ1OT1 on HSP90AA1 expression, H460 cell migration, and invasion. These data revealed a role for KCNQ1OT1 as an oncogene through miR-27b-3p/HSP90AA1 axis during NSCLC progression.     

Knockdown of lncRNA AK139328 alleviates myocardial ischaemia/reperfusion injury in diabetic mice via modulating miR‐204‐3p and inhibiting autophagy

This study was aimed at investigating the effects of lncRNA AK139328 on myocardial ischaemia/reperfusion injury (MIRI) in diabetic mice. Ischaemia/reperfusion (I/R) model was constructed in normal mice (NM) and diabetic mice (DM). Microarray analysis was utilized to identify lncRNA AK139328 overexpressed in DM after myocardial ischaemia/reperfusion (MI/R). RT‐qPCR assay was utilized to investigate the expressions of lncRNA AK139328 and miR‐204‐3p in cardiomyocyte and tissues. Left ventricular end diastolic diameter (LVEDD), left ventricular end systolic diameter (LVESD), left ventricular ejection fraction (LVEF) and fractioning shortening (FS) were obtained by transthoracic echocardiography. Haematoxylin‐eosin (HE) staining and Masson staining were utilized to detect the damage of myocardial tissues degradation of myocardial fibres and integrity of myocardial collagen fibres. Evans Blue/TTC staining was used to determine the myocardial infarct size. TUNEL staining was utilized to investigate cardiomyocyte apoptosis. The targeted relationship between lncRNA AK139328 and miR‐204‐3p was confirmed by dual‐luciferase reporter gene assay. MTT assay was used for analysis of cardiomyocyte proliferation. Western blot was utilized to investigate the expression of alpha smooth muscle actin (α‐SMA), Atg7, Atg5, LC3‐II/LC3‐I and p62 marking autophagy. Knockdown of lncRNA AK139328 relieved myocardial ischaemia/reperfusion injury in DM and inhibited cardiomyocyte autophagy as well as apoptosis of DM. LncRNA AK139328 modulated miR‐204‐3p directly. MiR‐204‐3p and knockdown of lncRNA AK139328 relieved hypoxia/reoxygenation injury via inhibiting cardiomyocyte autophagy. Silencing lncRNA AK139328 significantly increased miR‐204‐3p expression and inhibited cardiomyocyte autophagy, thereby attenuating MIRI in DM.     

MicroRNA-449b-5p targets HMGB1 to attenuate hepatocyte injury in liver ischemia and reperfusion

MicroRNAs (miRNAs) participate in the pathological process of liver ischemia/reperfusion (I/R) injury. MiR-449b-5p is the target miRNA of high mobility group box 1 (HMGB1). Its role and molecular mechanism in liver I/R injury remain unidentified. In this study, we found a protective effect of miR-449b-5p against hepatic I/R injury. HMGB1 expression significantly increased, whereas miR-449b-5p dramatically decreased in patients after liver transplant and in L02 cells exposed to hypoxia/reoxygenation (H/R). A dual-luciferase reporter assay confirmed the direct interaction between miR-449b-5p and the 3′ untranslated region of HMGB1 messenger RNA. We also found that overexpression of miR-449b-5p significantly promoted cell viability and inhibited cell apoptosis of L02 cells exposed to H/R. Moreover, miR-449b-5p repressed HMGB1 protein expression and nuclear factor-κB (NF-κB) pathway activation in these L02 cells. In an in vivo rat model of hepatic I/R injury, overexpression of miR-449b-5p significantly decreased alanine aminotransferase and aspartate aminotransferase and inhibited the HMGB1/NF-κB pathway. Our study thus suggests that miR-449b-5p alleviated hepatic I/R injury by targeting HMGB1 and deactivating the NF-κB pathway, which may provide a novel and promising therapeutic target for hepatic I/R injury.     

C5aR-mediated myocardial ischemia/reperfusion injury

The complement system activation can mediate myocardial ischemia and reperfusion (I/R). Inhibition of C5a activity reveals attenuation of I/R-induced myocardial infarct size. However, the contribution of C5a receptor (C5aR) to I/R injury remains to be unknown. Here, we reported that both mRNA and protein for the C5aR were constitutively expressed on cardiomyocytes and upregulated as a function of time after I/R-induced myocardial cell injury in mice. Blockade of C5aR markedly decreased microvascular permeability in ischemic myocardial area and leukocyte adherence to coronary artery endothelium. Importantly, the blocking of C5aR with an anti-C5aR antibody was associated with inhibition in activation of protein kinase C delta (PKC-delta) and induction of PKC-mediated mitogen-activated protein kinase phosphatases-1 (MKP-1) leading to the increased activity of p42/p44 mitogen-activated protein (MAP) kinase cascade. These data provide evidence that C5aR-mediated myocardial cell injury is an important pathogenic factor, and that C5aR blockade may be useful therapeutic targets for the prevention of myocardial I/R injury.     

Long non-coding RNA small nucleolar RNA host gene 1 alleviates the progression of recurrent spontaneous abortion via the microRNA-183-5p/ZEB2 axis

Long non-coding RNAs (lncRNAs) have been elucidated to play vital roles in the phenotype of trophoblast cells. Nevertheless, the effect of SNHG1 has not been investigated on trophoblast cells in recurrent spontaneous abortion (RSA). We aim to investigate the effect of SNHG1 on the phenotype of trophoblast cells during RSA. The RSA mice were established by mating female CBA/J mice with male DBA/2 mice. Microarray analysis was applied in RSA mice, and SNHG1 was identified as a significantly downregulated lncRNA. SNHG1 improved pregnancy outcome and reduced embryo resorption in RSA mice. Trophoblast cell proliferation, apoptosis, migration, and invasion were investigated by CCK8, EdU, TUNEL, wound healing, and Transwell assays. SNHG1 promoted proliferation, migration, and invasion of trophoblast cells, and reduced apoptosis. Mechanistically, SNHG1 bound to miR-183-5p in trophoblast cells. Moreover, miR-183-5p directly targeted ZEB2. Rescue experiment showed that ZEB2 silencing reversed the ameliorative effect of SNHG1 on pregnancy outcome and the promotion of trophoblast activity in RSA mice by impaired the Wnt/β-catenin pathway. In conclusion, we found that SNHG1 plays a critical role in the progression of RSA via miR-183-5p/ZEB2 and Wnt/β-catenin signaling. It has potential to be a therapeutic marker of RSA.     

Long non-coding RNA ZFAS1 regulates the malignant progression of gastric cancer via the microRNA-200b-3p/Wnt1 axis

Gastric cancer is a common malignant tumor. Studies from our laboratory or others have shown that long non-coding RNA (lncRNA) zinc finger antisense (ZFAS)1 often acts as an oncogene. However, the molecular underpinnings of how ZFAS1 regulates gastric cancer remain to be elucidated. Results showed that ZFAS1 expression was upregulated, and microRNA-200b-3p (miR-200b) expression was downregulated in gastric cancer tissues. MiR-200b overexpression suppressed the proliferation, cell cycle process, and Wnt/β-catenin signaling of gastric cancer cells. Subsequently, we identified miR-200b is a target of ZFAS1 and Wnt1 is a target of miR-200b. Furthermore, promotion of cancer malignant progression and activation of Wnt/β-catenin signaling induced by ZFAS1 was counteracted by increasing miR-200b expression. In vivo, ZFAS1 knockdown suppressed the tumorigenesis with the upregulated miR-200b and the inactive Wnt/β-catenin signaling. Summarily, we demonstrated a critical role of miR-200b in gastric cancer, and ZFAS1 can promote malignant progression through regulating miR-200b mediated Wnt/β-catenin signaling.     

Long non-coding RNA GAS5 aggravates myocardial depression in mice with sepsis via the microRNA-449b/HMGB1 axis and the NF-κB signaling pathway

Sepsis is a common cause of deaths of patients in intensive care unit. The study aims to figure out the role of long non-coding RNA (lncRNA) GAS5 in the myocardial depression in mice with sepsis. Cecal ligation and puncture (CLP) was applied to induce sepsis in mice, and then the heart function, myocardium structure, and the inflammatory response were evaluated. Differentially expressed lncRNAs in mice with sepsis were identified. Then gain- and loss-of-functions of GAS5 were performed in mice to evaluate its role in mouse myocardial depression. The lncRNA-associated microRNA (miRNA)–mRNA network was figured out via an integrative prediction and detection. Myocardial injury was observed by overexpression of high-mobility group box 1 (HMGB1) in septic mice with knockdown of GAS5 expression. Activity of NF-κB signaling was evaluated, and NF-κB inhibition was induced in mice with sepsis and overexpression of GAS5. Collectively, CLP resulted in myocardial depression and injury, and increased inflammation in mice. GAS5 was highly expressed in septic mice. GAS5 inhibition reduced myocardial depression, myocardial injury and inflammation responses in septic mice. GAS5 was identified to bind with miR-449b and to elevate HMGB1 expression, thus activating the NF-κB signaling. HMGB1 overexpression or NF-κB inactivation reduced the GAS5-induced myocardial depression and inflammation in septic mice. Our study suggested that GAS5 might promote sepsis-induced myocardial depression via the miR-449b/HMGB1 axis and the following NF-κB activation.     

Long noncoding RNA lncBRM promotes proliferation and invasion of colorectal cancer by sponging miR-204-3p and upregulating TPT1

Long noncoding RNAs (lncRNAs) are characterized as a type of noncoding RNAs over 200 nucleotides with little or none protein-coding potential. In the past years, lncRNAs have been proved to participant in many physiological and pathological processes. However, the role of lncRNAs in colorectal cancer (CRC) still needs more attentions. In our study, we found that lncBRM was highly expressed in CRC samples and the expression level of lncBRM was correlated with metastasis and advanced stage in CRC patients. And also, we showed that high expression of lncBRM predicted poor prognosis. Furthermore, we found that knockdown of lncBRM impaired the proliferation, migration and invasion of CRC cells while overexpressing of lncBRM promotes the proliferation, migration and invasion of CRC cells. Mechanically, we found that lncBRM served as a sponge of miR-204-3p that targeted TPT1. Highly expressed TPT1 can promote the proliferation, migration and invasion of CRC cells. In conclusion, we found that lncBRM was highly expressed in CRC and sponged miR-204-3p to modulate the expression of TPT1.     

热休克蛋白A5介导的自噬在小鼠脑缺血/再灌注损伤中的作用

目的：探讨热休克蛋白A5（HSPA5）诱导的自噬在小鼠脑缺血/再灌注损伤中的作用。方法：将36只BALB/c小鼠随机分为sham、缺血再灌注（I/R）、vehicle + I/R、3-甲基腺嘌呤（3-MA） + I/R、scramble siRNA + I/R和HSPA5 siRNA + I/R组（n=6）。Sham组只进行手术操作,不插入线栓。I/R采用大脑中动脉阻塞（MCAO）60 min后再灌注24 h。Vehicle + I/R组和3-MA + I/R将5μl 0.9% NaCl或3-MA （30 mg/ml）在MCAO前30 min侧脑室注射。scramble siRNA + I/R组和HSPA5 siRNA + I/R组将5μl scramble siRNA或HSPA5 siRNA （2μg/μl）在MCAO前24 h侧脑室注射。检测神经细胞内自噬体、缺血大脑皮层（LC3）-Ⅱ/LC3-I表达、神经元损伤程度及神经功能缺损。结果：显微镜下sham组小鼠大脑皮层神经细胞形态正常;I/R组小鼠缺血大脑皮层神经元胞质中细胞器减少,自噬体形成。与sham组比较,I/R组缺血大脑皮层LC3-Ⅱ/LC3-I蛋白表达水平显著增高（P < 0.05）;与I/R组相比,3-MA + I/R组或HSPA5 siRNA + I/R组缺血大脑皮层LC3-Ⅱ/LC3-I蛋白表达明显减少（P < 0.05）;3-MA + I/R组及HSPA5 siR-NA + I/R组I/R后脑缺血性损伤及神经系统症状加重（P < 0.05）。结论：HSPA5诱导自噬可能在小鼠局灶性I/R损伤中发挥保护作用。