Long noncoding RNA SNHG7 promotes the progression and growth of glioblastoma via inhibition of miR-5095

LINC01579 promotes cell proliferation by acting as a ceRNA of miR-139-5p to upregulate EIF4G2 expression in glioblastoma

Glioblastoma (GBM), a malignant and lethal tumor, remains a big threat to human health and life. Increasing explorations have confirmed that long noncoding RNAs are involved in the tumorigenesis and development of multiple cancers. Nevertheless, the regulatory mechanism of (long intergenic nonprotein coding RNA 1579 LINC01579) in GBM remains to be investigated. In this study, the expression of LINC01579 was upregulated in GBM cells and LINC01579 knockdown inhibited cell proliferation as well as promoted cell apoptosis. Additionally, LINC01579 acted as a sponge for miR-139-5p in GBM and eukaryotic translation initiation factor 4 gamma 2 (EIF4G2) was found to be a downstream target of miR-139-5p. Furthermore, the positive correlation of LINC01579 and EIF4G2 as well as the converse correlation between miR-139-5p and LINC01579 (or EIF4G2) were revealed by the experiments. Based on rescue assays, EIF4G2 overexpression or miR-139-5p inhibitor partially recovered the function of LINC01579 knockdown on cell proliferation and apoptosis. In summary, the results of this study verified that LINC01579 modulated cell proliferation and cell apoptosis in GBM by competitively binding with miR-139-5p to regulate EIF4G2, which provided a new clue to figure out potential therapy for patients suffered from GBM.

Loss of lncRNA-SNHG7 Promotes the Suppression of Hepatic Stellate Cell Activation via miR-378a-3p and DVL2

Small nuclear RNA host gene 7 (SNHG7), a novel long non-coding RNA (lncRNA), acts as an oncogene in cancers. However, whether SNHG7 is involved in hepatic stellate cell (HSC) activation during liver fibrosis is still unclear. In this study, upregulation of SNHG7 was found in vivo and in vitro during liver fibrosis. Silencing of SNHG7 led to the suppression of HSC activation, with a reduction in cell proliferation and collagen expression. SNHG7 knockdown also resulted in the suppression of liver fibrosis in vivo. Interestingly, miR-378a-3p was a target of SNHG7. SNHG7 and miR-378a-3p were co-located in the cytoplasm. Downregulation of miR-378a-3p blocked down the effects of loss of SNHG7 on HSC activation. Notably, SNHG7 could enhance Wnt/β-catenin pathway activation to contribute to liver fibrosis, with an increase in T cell factor (TCF) activity and a reduction in P-β-catenin level. It was found that miR-378a-mediated dishevelled segment polarity protein 2 (DVL2) was responsible for SNHG7-activated Wnt/β-catenin pathway. DVL2 was confirmed as a target of miR-378a-3p. SNHG7-induced HSC activation was almost blocked down by DVL2 knockdown. Accordingly, enhanced Wnt/β-catenin by SNHG7 was suppressed by loss of DVL2. Collectively, we demonstrate that SNHG7 reduces miR-378a-3p and attenuates its control on DVL2, leading to aberrant Wnt/β-catenin activity, which contributes to liver fibrosis progression.

Long noncoding RNA HAGLROS promotes cell proliferation, inhibits apoptosis and enhances autophagy via regulating miR-5095/ATG12 axis in hepatocellular carcinoma cells

In this research, we planned to dig the possible influences and mechanism of long noncoding (lnc) RNA HAGLROS in the development and progression of hepatocellular carcinoma (HCC). The levels of lncRNA HAGLROS in HCC tumor samples and their relationship with clinicopathological characteristics and prognosis of patients with HCC were studied. Subsequently, overexpression and silenced approaches were used in HCC cells for detecting the effects of lncRNA HAGLROS on cell viability, apoptosis, and autophagy. Furthermore, we investigated whether HAGLROS could function as a competing endogenous RNA (ceRNA) to regulate miR-5095 expression in HCC cells, and explored the correlation between miR-5095 and ATG12. Besides, the correlation of HAGLROS, the consequent PI3K/AKT/mTOR signaling pathway was further explored. The level of HAGLROS was higher in HCC tissues and correlated with clinical performances including tumor stages or tumor differentiation. In contrast to the lower level, a higher level of HAGLROS correlated with a shorter survival time of patients with HCC. The suppression of HAGLROS decreased cell viability, promoted apoptosis, and inhibited autophagy. Moreover, HAGLROS negatively regulated miR-5095 expression, which further regulated HCC cell viability, apoptosis, and autophagy. In addition, ATG12 was targeted by miR-5095 and was then involved in miR-5095-regulated HCC cell biological processes including viability, apoptosis, and autophagy. Furthermore, overexpression of HAGLROS activated PI3K/AKT/mTOR signals. Our results revealed that HAGLROS is highly expressed in HCC, and its high level may correlate with the progression and development of HCC involving the processes of cell viability, apoptosis, and autophagy through the miR-5095/ATG12 axis and PI3K/AKT/mTOR signals.

Knockdown of lncRNA LEF1-AS1 inhibited the progression of oral squamous cell carcinoma (OSCC) via Hippo signaling pathway

It is verified that long non-coding RNAs (lncRNAs) play crucial roles in various cancers. LncRNA LEF1-AS1 is a reported oncogene in colorectal cancer and glioblastoma. In this study, we unveiled that LEF1-AS1 markedly increased in oral squamous cell carcinoma (OSCC) tissues and cell lines. Besides, OSCC patients with high levels of LEF1-AS1 were apt to poor prognosis. Functionally, LEF1-AS1 knockdown inhibited cell survival, proliferation and migration, whereas enhanced cell apoptosis and induced G0/G1 cell cycle arrest in vitro. Consistently, LEF1-AS1 silence hindered tumor growth in vivo. Moreover, LEF1-AS1 inhibition stimulated the activation of Hippo signaling pathway through directly interacting with LATS1. Furtherly, we disclosed that LEF1-AS1 silence abolished the interaction of LEF1-AS1 with LATS1 while enhanced the binding of LATS1 to MOB, therefore promoting YAP phosphorylation but impairing YAP1 nuclear translocation. Additionally, we demonstrated that LEF1-AS1 regulated YAP1 translocation via a LATS1-dependent manner. Furthermore, we also uncovered that YAP1 overexpression abolished the suppressive impact of LEF1-AS1 repression on the biological processes of OSCC cells. In a word, we concluded that LEF1-AS1 served an oncogenic part in OSCC through suppressing Hippo signaling pathway by interacting with LATS1, suggesting the therapeutic and prognostic potential of LEF1-AS1 in OSCC.

Silencing of a novel lncRNA LOC105369748 suppresses the progression of hepatocellular carcinoma by sponging miR-5095 from MBD2

A growing number of studies have suggested that long noncoding RNAs (lncRNAs) play critical roles in human malignant cancers, including hepatocellular carcinoma (HCC). However, the functions of most lncRNAs have not been elucidated in HCC. In the present study, we explored the potential functions of a novel lncRNA LOC105369748 in the HCC progression. We identified that LOC105369748 expression was significantly elevated in HCC tissues compared with normal tissues based on bioinformatics analysis, quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis and in situ hybridization (ISH) examination. Moreover, we found that the LOC105369748 overexpression was associated with poor prognosis in patients with HCC. Then we measured the effects of LOC105369748 on HCC cell proliferation, migration, invasion, and epithelial-to-mesenchymal transition (EMT). And our results demonstrated that LOC105369748 exerted oncogenic roles. In terms of mechanism, LOC105369748 was shown to promote MBD2 expression through competitively binding to microRNA(miR)-5095 in HCC. In conclusion, our findings elucidate that the LOC105369748/miR-5095/MBD2 signaling axis regulates the HCC progression and may be a novel therapeutic avenue.

LncRNA SNHG7 promotes pancreatic cancer proliferation through ID4 by sponging miR-342-3p

BACKGROUND

Small nucleolar RNA host gene 7 (SNHG7) is a novel identified oncogenic gene in tumorigenesis. However, the role that SNHG7 plays in pancreatic cancer (PC) remains unclear. In this study, we aimed to investigate the functional effects of SNHG7 on PC and the possible mechanism.

METHODS

The expression levels of SNHG7 in tissues and cell lines were measured by RT-qPCR. Cell viability, apoptosis, migration and invasion were examined to explore the function of SNHG7 on PC. Bioinformatics methods were used to predict the target genes. The mechanism was further investigated by transfection with specific si-RNA, miRNA mimics or miRNA inhibitor. Tumor xenograft was carried out to verify the effects of SNHG7 in vivo.

RESULTS

We found that SNHG7 was overexpressed in both PC tissues and cell lines. High expression level of SNHG7 was correlated with the poor prognosis. SNHG7 knockdown inhibited the proliferation, migration and invasion of PC cells. Moreover, SNHG7 was found to regulate the expression of ID4 via sponging miR-342-3p. Additionally, this finding was supported by in vivo experiments.

CONCLUSIONS

LncRNA SNHG7 was overexpressed in PC tissues, and knockdown of SNHG7 suppressed PC cell proliferation, migration and invasion via miR-342-3p/ID4 axis. The results indicated that SNHG7 as a potential target for clinical treatment of PC.

Genome-wide discovery and characterization of flower development related long non-coding RNAs in Prunus mume

BACKGROUND

Long non-coding RNAs (lncRNAs) are transcripts more than 200 bp in length do not encode proteins. Up to the present, it has been reported that lncRNAs play an essential role in developmental processes through their regulatory functions. However, their characteristics, expression inheritance patterns, and functions in Prunus mume are quite unidentified.

RESULTS

In this present study, we exposed the specific characters of pistil development process between single pistil cv 'Qingjia No.2' (QJN2) and multiple pistils cv 'Da Yu' (DY). We found that early October is the key stage for pistil differentiation. The similarity epidermis was observed between two types of pistil. We also further investigated a complete pistil development lncRNA profiles through RNA-seq in Prunus mume. 2572 unique lncRNAs and 24,648 genes mapped to Prunus mume genome, furthermore, 591 novel lncRNAs were predicted. Both unique lncRNAs and novel lncRNAs are shorter in length than the mRNAs, and the overall expression level of lncRNAs was lower than mRNAs in Prunus mume. 186 known lncRNAs, 1638 genes and 89 novel lncRNAs were identified as significant differential expressed in QJN2 compared with DY. We predicted 421 target genes of differentially expressed known lncRNAs (DEKLs) and 254 target genes of differentially expressed novel lncRNAs (DENLs). 153 miRNAs were predicted interacted with 100 DEKLs while 112 miRNAs were predicted interacted with 55 DENLs. Further analysis of the DEKLs showed that the lncRNA of XR_514690.2 down-regulated its target ppe-miR172d, and up-regulated AP2, respectively. Meanwhile, the other lncRNA of TCONS_00032517 induced cytokinin negative regulator gene A-ARR expression via repressing its target miRNA ppe-miR160a/b in DY. At the same time we found that the AP2 expression was significantly up-regulated by zeatin (ZT) treatment in flower buds. Our experiments suggest that the two lncRNAs of XR_514690.2 and TCONS_00032517 might contribute the formation of multiple pistils in Prunus mume.

CONCLUSION

This study shows the first characterization of lncRNAs involved in pistil development and provides new indications to elucidate how lncRNAs and their targets play role in pistil differentiation and flower development in Prunus mume.

Knockdown of long non-coding RNA SNHG5 inhibits malignant cellular phenotypes of glioma via Wnt/CTNNB1 signaling pathway

Objective: Human brain glioma is the most malignant primary intracranial tumor, which has poor prognosis and high mortality. Long noncoding RNAs are considered to take part in cellular phenotypes and are emerging as diagnostic and prognostic biomarkers of glioma. This study will research the effects of Small Nucleolar RNA Host Gene 5 (SNHG5) gene on malignant cellular phenotypes in glioma and explore the possible mechanisms. Materials and Methods: The expression level of SNHG5 was examined using quantitative Real-time PCR in glioma tissues and cell lines. Loss-of-function experiments of SNHG5 together with Enhanced Cell Counting Kit-8, flow cytometry and cell invasion assay were used to investigate the effects of SNHG5 on malignant cellular phenotypes of glioma cells. Finally, luciferase assay and western blotting were applied to determine the activity of WNT/CTNNB1 signaling pathway. Results: SNHG5 gene was high-expressed in glioma tissues and cell lines. Knockdown of SNHG5 gene depressed cell proliferation and invasiveness as well as promoted the apoptosis of U251 and U87 cells. In addition, online database analysis showed SNHG5 was closely related to Wnt/CTNNB1 signaling pathway. Knockdown of SNHG5 inactivated Wnt/CTNNB1 signaling pathway, and the activating of Wnt/CTNNB1 signaling pathway partly restored the influences of SNHG5 knockdown on malignant cellular phenotypes of U251 and U87 cells. Conclusion: SNHG5 gene was high-expressed in glioma, knockdown of SNHG5 inhibits malignant cellular phenotypes of glioma via Wnt/CTNNB1 signaling pathway.

LncRNA TP73-AS1 promoted the progression of lung adenocarcinoma via PI3K/AKT pathway

Lung adenocarcinoma (LAD) is one of the most common malignancies that threats human health worldwide. Long non-coding RNAs (lncRNAs) have been reported to play significant roles in tumorigenesis and might be novel biomarkers and targets for diagnosis and treatment of cancers. TP73-AS1 is a newly discovered lncRNA involved in the tumorigenesis and development of several cancers. However, its role in LAD has not been investigated yet. In the present study, we first found that TP73-AS1 expression was markedly increased in LAD tissues and cell lines and its overexpression was strongly associated with poor clinical outcomes. Then the loss/gain-of-function assays elucidated that TP73-AS1 contributed to cell proliferation, migration, and invasion in vitro, and the in vivo experiments illustrated that its knockdown inhibited tumor growth and metastasis. What was more, we discovered that phosphoinositide 3-kinase and AKT (PI3K/AKT) pathway was activated both in LAD tissues and cell lines but inactivated under TP73-AS1 silence. Moreover, the activation of this pathway could rescue the inhibitory effects of TP73-AS1 suppression on LAD cellular processes partially. These data suggested that TP73-AS1 served as an oncogene in LAD partially through activating PI3K/AKT pathway and it could be a potential target for diagnosis and treatment of LAD.

Role of SNHG7-miR-653-5p-STAT2 feedback loop in regulating neuroblastoma progression

Long noncoding RNAs (lncRNAs) are reported to be involved in the pathology of numerous cancers, including neuroblastoma (NB). lncRNA SNHG7 has been recognized as a carcinogen in several cancers, but its role in NB progression remains unknown. Our study revealed that SNHG7 expression was markedly higher in NB tissues than that in nontumor tissues. Besides, upregulated SNHG7 was greatly correlated with poor overall survival of NB patients. Functionally, the loss-of-function assays demonstrated that knockdown of SNHG7 inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition in NB cells. Mechanically, the bioinformatics analysis predicted that miR-653-5p was the shared partner of SNHG7 and signal transducer and activator of transcription 2 (STAT2). Unsurprisingly, we further confirmed that SNHG7 could interact with miR-653-5p and therefore functioned as the ceRNA of STAT2 so as to regulate STAT2 expression in NB cells. Moreover, STAT2 expression was in inverse proportion to miR-653-5p level but in positive proportion to SNHG7 level in NB tissues. Importantly, the repressed NB progression induced by silenced SNHG7 was reversed by STAT2 overexpression or miR-653-5p inhibitors. Jointly, our findings elucidated SNHG7 facilitated NB progression through the miR-653-5p/STAT2 pathway, providing a novel therapeutic target and prognostic biomarker for this disease.

Inhibition of malignant human bladder cancer phenotypes through the down-regulation of the long non-coding RNA SNHG7

There is abundant evidence that long non-coding RNAs play important roles in the development of tumors. In the present study, our main aim was to explore the relationship between lncRNA SNHG7 and human bladder cancer cells, thus finding a novel target for bladder cancer therapy and diagnosis. Expression of lncRNA SNHG7 was evaluated using real-time quantitative polymerase chain reaction in bladder tumor tissues and paired adjacent normal tissues from 72 patients diagnosed with urothelial bladder carcinoma. We analyzed the differences in expression according to grading and staging. Human bladder cancer cell lines UMUC, 5637, T24 and SW780 were transiently transfected with lncRNA SNHG7-specific siRNA and negative control siRNA. The changes in malignant phenotypes in transfected bladder cancer cells were determined using CCK-8 assay, wound-healing assay and ELISA. We found that lncRNA SNHG7 was correlated with human bladder cancer. lncRNA SNHG7 was overexpressed in bladder cancer tissues compared to paired normal tissues and expression of SNHG7 was higher in high-grade than low-grade tumors. The malignant phenotypes were significantly inhibited when we inhibited expression of lncRNA SNHG7 in several bladder cell lines. SNHG7 plays an oncogenic role in human bladder cancer and may be a potential novel therapeutic target for treating bladder cancer.

MicroRNA‑3666 suppresses the growth and migration of glioblastoma cells by targeting KDM2A

MicroRNAs (miRNAs) are acknowledged as essential regulators in human cancer types, including glioblastoma (GBM). However, the functions of microRNA-3666 (miR-3666) in GBM remain unclear. In the present study, it was identified that the expression of miR-3666 was significantly downregulated in GBM tissues compared with adjacent normal tissues by reverse transcription-quantitative polymerase chain reaction. Additionally, miR-3666 was downregulated in GBM cell lines. Furthermore, it was observed that the miR-3666 expression level in patients with GBM was associated with prognosis. With functional experiments, it was identified that overexpression of miR-3666 significantly inhibited the proliferation, migration and invasion of GBM cells in vitro by Cell Counting kit-8 and Transwell assays. Ectopic expression of miR-3666 significantly arrested GBM cells in the G₀ phase by fluorescence activated cell sorting. In terms of the underlying mechanism, it was identified that lysine-specific demethylase 2A (KDM2A) is a direct target of miR-3666 in GBM cells. Overexpression of miR-3666 significantly decreased the expression of KDM2A in GBM cells. Furthermore, it was observed that knockdown of KDM2A significantly suppressed the proliferation, migration and invasion of GBM cells. Collectively, the present results demonstrated that the miR-3666/KDM2A axis serves an important role in the progression of GBM, which provides novel insight into the development of therapeutic strategies for GBM treatment.

Knockdown of lncRNA SNHG7 inhibited cell proliferation and migration in bladder cancer through activating Wnt/β-catenin pathway

It is identified that long non-coding RNAs (lncRNAs) play important roles in tumorigenesis. LncRNA SNHG7 has been found to be an oncogene in varieties of tumors including bladder cancer. However, its potential regulatory mechanism in bladder cancer still remains unknown. In this study, we discovered that the expression levels of SNHG7 were significantly increased in bladder cancer tissues and cell lines. Patients with high expression level of SNHG7 suffered from poor prognosis. Additionally, knockdown of SNHG7 induced declined cell viability, proliferation as well as G0/G1 cell cycle arrest. Furthermore, we found that cell migratory ability was markedly reduced after silencing SNHG7. Next, we verified that knockdown of SNHG7 reduced the protein level of β-catenin and thus decreased the level of its downstream targets including c-myc, cyclin D1 and E-cadherin, implying that SNHG7 might impact bladder cancer via Wnt/β-catenin pathway. Subsequently, the rescue assays performed in SNHG7 silenced T24 cells by using activator of Wnt/β-catenin signaling elucidated that re-activation of this pathway partly restored the inhibitory effects of SNHG7 suppression on biological behaviors of T24 cells. Collectively, SNHG7 elicited carcinogenic functions in bladder cancer partially via activating Wnt/β-catenin signaling pathway, suggesting a potential target for the treatment and prognosis of bladder cancer.

Long noncoding RNA AFAP1‑AS1 enhances cell proliferation and invasion in osteosarcoma through regulating miR‑4695‑5p/TCF4‑β‑catenin signaling

Long noncoding RNA AFAP1‑AS1 has been shown to promote tumor progression in several human cancer types, such as thyroid cancer, tongue squamous cell carcinoma and lung cancer. However, the role of AFAP1‑AS1 in osteosarcoma (OS) has not been investigated. In the present study, the expression of AFAP1‑AS1 was significantly upregulated in OS tissues and cell lines. Moreover, AFAP1‑AS1 expression was negatively correlated with OS patient prognosis. Besides, AFAP1‑AS1 knockdown significantly inhibited the proliferation and invasion of OS cells in vitro. Furthermore, in vivo xenograft experiments indicated that AFAP1‑AS1 depletion delayed tumor growth. Regarding the underlying mechanism, AFAP1‑AS1 served as a sponge to repress the level of microRNA (miR)‑4695‑5p, which targeted transcription factor (TCF)4, a pivot effector of Wnt/β‑catenin signaling pathway. It was demonstrated that overexpression of AFAP1‑AS1 inhibited the expression of miR‑4695‑5p, while miR‑4695‑5p overexpression decreased TCF4 expression and reduced activation of Wnt/β‑catenin pathway. Through rescue assays, it was demonstrated that restoration of TCF4 expression reversed the effects of AFAP1‑AS1 knockdown or miR‑4695‑5p overexpression on OS cells. Taken together, these findings demonstrated that the AFAP1‑AS1/miR‑4695‑5p/TCF4‑β‑catenin axis played an important role in OS progression.

Dioscin protects against coronary heart disease by reducing oxidative stress and inflammation via Sirt1/Nrf2 and p38 MAPK pathways

Cardiovascular diseases are common diseases in Sweden as in most countries. In 2016, 25,700 persons suffered from coronary heart disease (CHD) and 25% of these died within 28 days. The present study investigated whether dioscin may exert protective effects against CHD‑induced heart apoptosis, oxidative stress and inflammation in a pig model and the potential underlying mechanisms. Adult pigs were used to establish a CHD model group and 80 mg/kg dioscin was administered for 4 weeks. Histological analysis and measurement of serum levels of heart injury markers demonstrated that 80 mg/kg dioscin markedly alleviated CHD, while left ventricular ejection fraction and left ventricular systolic internal diameter measurements indicated that 80 mg/kg dioscin also increased heart function in the CHD pig model. Furthermore, western blotting demonstrated that 80 mg/kg dioscin significantly reduced protein levels of apoptosis markers in the heart of CHD model pigs, including Bcl‑2‑associated X and caspase‑3, potentially via the suppression of poly (ADP‑ribose) polymerase 1 (PARP)/p53 expression. Additionally, the results of ELISA and western blotting demonstrated that 80 mg/kg dioscin may reduce oxidative stress and inflammation in CHD model pigs through the promotion of sirtuin 1 (Sirt1)/nuclear factor erythroid 2‑related factor 2 (Nrf2) protein expression and the suppression of PARP/p53 and p38 mitogen‑activated protein kinase (MAPK) expression. The results of the current study indicate that dioscin may protect against CHD by regulating oxidative stress and inflammation via Sirt1/Nrf2 and p38 MAPK pathways.