TGFβ mediated LINC00273 upregulation sponges mir200a-3p and promotes invasion and metastasis by activating ZEB1

Transforming growth factor β (TGFβ) is a prominent cytokine that promotes tumor progression by activating epithelial-to-mesenchymal transition (EMT). This study indicated that TGFβ exerted metastasis by inducing zinc finger E-box binding homeobox 1 (ZEB1) and a long noncoding RNA, LINC00273, expressions in A549 cells. Knocking down LINC00273 diminished TGFβ induced ZEB1 expression as well as metastasis. Mechanistically, LINC00273 acted as a molecular sponge of microRNA (miR)-200a-3p which liberate ZEB1 to perform its prometastatic functions. LINC00273 knockdown and miR200a3p mimic transfection of A549 cells were used for validating the link between TGFβ and LINC00273 induced metastasis. RNA pulldown and luciferase assay were performed to establish mir200a-3p-LINC00273 interaction. High expressions of LINC00273, TGFβ, and ZEB1 with concurrent low miR200a-3p expression had been verified in vivo and in patient samples. Overall, LINC00273 promoted TGFβ-induced lung cancer EMT through miR-200a-3p/ZEB1 feedback loop and may serve as a potential target for therapeutic intervention in lung cancer metastasis.     

Deregulation of UCA1 expression may be involved in the development of chemoresistance to cisplatin in the treatment of non-small-cell lung cancer via regulating the signaling pathway of microRNA-495/NRF2

Non-small-cell lung cancer (NSCLC) remains the leading cause of cancer death worldwide. As a platinum-based chemotherapeutic drug, cisplatin has been used for over 30 years in NSCLC treatment while its effects are diminished by drug resistance. Therefore, we aimed to study the potential role of UCA1 in the development of chemoresistance against cisplatin. Real-time polymerase chain reaction, western-blot analysis, and immunofluorescence were used to study the involvement of UCA1, miR-495, and NRF2 in chemoresistance against cisplatin. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to determine the effect of cisplatin on cell proliferation. Computational analysis and luciferase assay were carried out to explore the interaction among UCA1, miR-495, and NRF2. The cisplatin-R group exhibited lower levels of UCA1 and NRF2 expression but a higher level of miR-495 expression than the cisplatin-S group. The growth rate and half-maximal inhibitory concentration of cellular dipeptidyl peptidase (cisplatinum) of the cisplatin-R group were much higher than those in the cisplatin-S group. MiR-495 contained a complementary binding site of UCA1, and the luciferase activity of wild-type UCA1 was significantly reduced after the transfection of miR-495 mimics. MiR-495 directly targeted the 3′-untranslated region (3′-UTR) of NRF2, and the luciferase activity of wild-type NRF2 3′-UTR was evidently inhibited by miR-495 mimics. Finally, UCA1 and NRF2 expressions in the effective group were much lower than that in the ineffective group, along with a much higher level of miR-495 expression. We suggested for the first time that high expression of UCA1 contributed to the development of chemoresistance to cisplatin through the UCA1/miR-495/NRF2 signaling pathway.     

Long noncoding RNA LINC00319 regulates ROMO1 expression and promotes bladder cancer progression via miR-4492/ROMO1 axis

Growing reports indicate that long noncoding RNA (lncRNA) are involved in the regulation of various biological processes of cancer cells. LINC00319 is an ill investigated lncRNA and has been shown to regulate lung cancer, nasopharyngeal carcinoma and ovarian cancer. Nevertheless, its roles in bladder cancer (BCa) remain unclear. In our research, LINC00319 was shown to be an upregulated lncRNA in BCa tissues. LINC00319 expression is negatively correlated with the patient's prognosis. Silencing of LINC00319 suppressed BCa proliferation and invasiveness. In addition, the data indicated LINC00319 was a sponge for miR-4492 and miR-4492 suppressed ROMO1 expression in BCa. Furthermore, our results illustrated miR-4492/ROMO1 axis regulates proliferation, migration, and invasion and LINC00319 exerts oncogenic roles through modulating miR-4492/ROMO1 axis. In sum, this study suggested that LINC00319 acts as oncogenic roles in BCa progression.     

miR-122-5p promotes aggression and epithelial-mesenchymal transition in triple-negative breast cancer by suppressing charged multivesicular body protein 3 through mitogen-activated protein kinase signaling

Triple-negative breast cancer (TNBC) is highly metastatic and frequently has a poor prognosis. The lack of comprehension of TNBC and gene therapy targets has led to limitedly effective treatment for TNBC. This study was conducted to better understand the molecular mechanism behind TNBC progression, and to find out promising gene therapy targets for TNBC. Herein the influence of miR-122-5p's binding charged multivesicular body protein 3 (CHMP3) 3′-untranslated region (3′-UTR) on in TNBC cells was investigated. in vitro experiments quantitative real-time polymerase chain reaction, immunoblot analysis, dual-luciferase reporter gene assay, cell counting assay, transwell invasion assay, and flow cytometry-determined cell apoptosis assay were employed. We also used TargetScan Human 7.2 database to find out the target relationship between miR-122-5p and CHMP3 3′-UTR. TImer algorithm was used to provide an overview of the expression of CHMP3 gene across human pan-cancer, to predict the survival outcome of breast cancer patients, and to predict the correlation between CHMP3 gene expression and epithelial-mesenchymal transition (EMT) and mitogen-activated protein kinase (MAPK)-related gene expression. CHMP3 gene was significantly downregulated across a wide range of human cancers including breast cancer (BRCA). A higher level of CHMP3 gene predicted a better 3- and 5-year survival outcome of patients with BRCA. In our experiments, miR-122-5p was significantly upregulated and CHMP3 gene was significantly downregulated in TNBC cells compared with normal cell line. miR-122-5p mimics enhanced TNBC cell viability, proliferation, and invasion whereas the upregulation of CHMP3 gene led to an opposite outcome. Forced expression of miR-122-5p suppressed cell apoptosis, compelled EMT and MAPK signaling whereas forced expression of CHMP3 did the opposite. We then conclude that miR-122-5p promotes aggression and EMT in TNBC by suppressing CHMP3 through MAPK signaling.     

LINC00205 modulates the expression of EPHX1 through the inhibition of miR-184 in hepatocellular carcinoma as a ceRNA

Several studies have shown that low expression of epoxide hydrolase 1 (EPHX1) is closely associated with varying human cancers, including hepatocellular carcinoma (HCC). This study aims to explore the potential mechanism of EPHX1 silencing and revealed a novel regulatory pathway in the pathogenesis of HCC. In this study, micro ribonucleic acid (miR)-184 was predicted and validated to be a regulator of EPHX1 through experiments, and its expression was negatively correlated with the messenger RNA (mRNA) levels of EPHX1 in primary tumors. Elevation of EPHX1 suppressed cell proliferation and migration as well as cell cycle progression, and induced apoptosis, while downregulation of miR-184 exhibited the opposite effect on cellular processes. Moreover, LINC00205 interacted with miR-184 and was markedly downregulated in tumors. The effects of the miR-184 inhibitor on cell proliferation, apoptosis, and migration were reversed in part by the transfection with LINC00205 small interfering RNAs. In addition, LINC00205 acted as a molecular sponge to positively regulate the mRNA and protein levels of EPHX1 via regulating miR-184. The tumorigenicity of HCC cells was enhanced by LINC00205 shRNA but diminished by overexpression of EPHX1 in vivo. Clinically, the EPHX1 expression in patients with HCC was markedly downregulated. Taken together, the results of this study suggest that as a competing endogenous RNA, LINC00205 may regulate EPHX1 by inhibiting miR-184 in the progression of HCC and that targeting the LINC00205/miR-184/EPHX1 axis may provide a treatment protocol for patients.     

Exercise protects the heart against myocardial infarction through upregulation of miR-1192

Myocardial infarction (MI) is known as a serious global problem, which has a high mortality rate and cause severe heart damage. Mounting evidence has suggested that exercise provides direct endogenous cardiac protection against various cardiovascular diseases including MI. However, the underlying mechanism of exercise’s cardioprotective effect against MI has not been fully understood. Here, we found that a 4-wk swim training exerted protective effects against MI in C57 mice, as evidenced by increased cardiac function and decreased cardiac apoptosis. A plasma miRNA profiling assay was then performed, and 10 differentially expressed miRNAs were detected. Among them, miR-1192 was increased after exercise, and it exerted significant protective effect against hypoxia in cultured neonatal cardiomyocytes. In addition, intramyocardially injection of agomiR-1192 exerted similar cardioprotective effect as exercise, and inhibition of miR-1192 using antgomiR-1192 abolished the cardioprotective effect of exercise in MI mice, suggesting that exercise exerted cardioprotection against MI through upregulation of miR-1192. Furthermore, we found that miR-1192 exerted cardioprotective effect via targeting caspase 3 in cardiomyocytes. These findings suggested that exercise protects the heart against MI through upregulation of miR-1192, and miR-1192 is a novel exerkine in exercise-induced cardioprotection against MI.     

lncRNA SNHG11 promotes lung cancer cell proliferation and migration via activation of Wnt/β-catenin signaling pathway

Lung cancer ranks topmost among the most frequently diagnosed cancers. Despite increasing research, there are still unresolved mysteries in the molecular mechanism of lung cancer. Long noncoding RNA small nucleolar RNA host gene 11 (SNHG11) was found to be upregulated in lung cancer and facilitated lung cancer cell proliferation, migration, invasion, and epithelial–mesenchymal transition progression while suppressed cell apoptosis. Moreover, the high expression of SNHG11 was correlated with poor prognosis of lung cancer patients, TNM stage, and tumor size. Further assays demonstrated that SNHG11 functioned in lung cancer cells via Wnt/β-catenin signaling pathway. Subsequently, Wnt/β-catenin pathway was found to be activated through SNHG11/miR-4436a/CTNNB1 ceRNA axis. As inhibiting miR-4436 could only partly rescue the suppression of cell function induced by silencing SNHG11, it was suspected that β-catenin might enter cell nucleus through other pathways. Mechanism investigation proved that SNHG11 would directly bind with β-catenin to activate classic Wnt pathway. Subsequently, in vivo tumorigenesis was also demonstrated to be enhanced by SNHG11. Hence, SNHG11 was found to promote lung cancer progression by activating Wnt/β-catenin pathway in two different patterns, implying that SNHG11 might contribute to lung cancer treatment by acting as a therapeutic target.     

MiR-34a inhibits the proliferation,migration, and invasion of oral squamous cell carcinoma by directly targeting SATB2

In various kinds of carcinomas, the special AT-rich sequence-binding protein 2 (SATB2) with its atypical expression promotes the metastasis and progression of the tumor, though in the oral squamous cell carcinoma (OSCC) its inherent mechanism and the status of SATB2 remain unclear. The role played by the SATB2 expression in the OSCC cell lines and tissue samples in the target of miR-34a downstream is the intended endeavor of this study. In te OSCCs the miR-34a expression was determined by quantitative real-time polymerase chain reaction (q-PCR), while the SATB2 expression in the cell lines and tissue samples in OSCC was analyzed with the q-PCR and the western blot. Studies in both in vitro and in vivo of the effects of miR-34a on the initiation of OSCC were conducted. As a direct target of the miR-34a the SATB2 was verified with the luciferase reporter assay. In cases where the miR-34a levels were low, the SATB2 in OSCCs seemed to be overexpressed. Besides, both in the in vitro and in vivo a suppression of migration, invasion, and cell growth was caused by miR-34a by down regulating the SATB2 expression. The SATB2 being a direct target of miR-34a was confirmed by the cotransfection of miR-34a mimics specifically the decrease in the expression of luciferase of SATB2–3′UTR-wt reporter. As a whole, our study confirmed the inhibition of miR-34a in the invasion, proliferation, and migration of the OSCCs, playing a potential tumor suppressor role with SATB2 as its downstream target.     

miR-181a/b-5p ameliorates inflammatory response in monocrotaline-induced pulmonary arterial hypertension by targeting endocan

Pulmonary arterial hypertension (PAH) is a progressive disorder characterized by vascular remodeling, endothelial cell (EC) dysfunction, and inflammation. The roles of microRNAs have received much critical attention. Thus, this study was attempted to show the biological function of miR-181a/b-5p (miR-181a/b) in monocrotaline (MCT)-induced PAH. Here, rats injected with MCT were used as PAH models. The expression of miR-181a/b and its effect on PAH pathologies were examined using miR-181a/b overexpression lentivirus. A luciferase reporter analysis was performed to measure the relationships between miR-181a/b and endocan. Additionally, primary rat pulmonary arterial endothelial cells (rPAECs) treated with tumor necrosis factor-α (TNF-α) were employed to further validate the regulatory mechanism of miR-181a/b in vitro. Our results showed that miR-181a/b expression was reduced in PAH, and its upregulation significantly attenuated the short survival period, right ventricular systolic pressure and mean pulmonary artery pressure increments, right ventricular remodeling, and lung injury. Furthermore, the increase of intercellular cell adhesion molecule-1 (ICAM1) and vascular cell adhesion molecule-1 (VCAM1) in PAH rats was inhibited by miR-181a/b overexpression. Similarly, our in vitro results showed that inducing miR-181a/b suppressed TNF-α-stimulated increase of ICAM1 and VCAM1 in rPAECs. Importantly, the increased expression of endocan in PAH model or TNF-α-treated rPAECs was restored by miR-181a/b upregulation. Further analysis validated the direct targeting relationships between miR-181a/b and endocan. Collectively, this study suggests that miR-181a/b targets endocan to ameliorate PAH symptoms by inhibiting inflammatory states, shedding new lights on the prevention and treatment of PAH.