Long noncoding RNA SNHG1 promotes non-small cell lung cancer progression by up-regulating MTDH via sponging miR-145-5p

Retracted Article: Long non-coding RNA PCAT1 facilitates cell growth in multiple myeloma through an MTDH-mediated AKT/β-catenin signaling pathway by sponging miR-363-3p

Multiple Myeloma (MM) is a plasma cell myeloma.

lncRNA PCAT6 promotes non-small cell lung cancer cell proliferation, migration and invasion through regulating miR-330-5p

Background

Investigating the roles of lncRNA prostate cancer-associated transcript 6 (PCAT6) in modulating the growth and aggressiveness of non-small-cell lung carcinoma (NSCLC) cell.

Method

The levels of PCAT6 in NSCLC tissues and cell lines were determined by quantitative real-time PCR assay. MTT as well as colony formation assays were applied to explore the effect of PCAT6 on the growth of NSCLC cell in vitro. Wound healing and Transwell assays were utilized to analyze the impact of PCAT6 on the migration and invasion of NSCLC cell. Bioinformatics analysis and luciferase reporter assay were used to prove that miR-330-5p was the target of PCAT6. Colony formation, wound healing, and Transwell invasion assays were applied to demonstrate that PCAT6 promoted NSCLC cell growth, migration, and invasion through binding miR-330-5p. Finally, xenograft model was used to explore the role of PCAT6 in the tumor growth of NSCLC cell in vivo.

Results

PCAT6 was highly overexpressed in NSCLC tissues and cells compared with normal tissues and non-tumorigenic bronchial epithelial cell line, BEAS-2B. Downregulation of PCAT6 markedly reduced the proliferation, migration, and invasion of NSCLC cell. Moreover, down-expression of PCAT6 significantly increased the level of miR-330-5p in NSCLC cell. Further functional experiments indicated that down-expression of miR-330-5p reversed the inhibitory effect of PCAT6 on NSCLC cell growth, migration, and invasion.

Conclusion

Our results reveal that lncRNA PCAT6 facilitates the proliferation, migration, and invasion of NSCLC cell via competitively binding to miR-330-5p.

Transcriptomic and functional network features of lung squamous cell carcinoma through integrative analysis of GEO and TCGA data

Lung squamous cell carcinoma (LUSC) is associated with poor clinical prognosis and lacks available targeted therapy. Novel molecules are urgently required for the diagnosis and prognosis of LUSC. Here, we conducted our data mining analysis for LUSC by integrating the differentially expressed genes acquired from Gene Expression Omnibus (GEO) database by comparing tumor tissues versus normal tissues (GSE8569, GSE21933, GSE33479, GSE33532, GSE40275, GSE62113, GSE74706) into The Cancer Genome Atlas (TCGA) database which includes 502 tumors and 49 adjacent non-tumor lung tissues. We identified intersections of 129 genes (91 up-regulated and 38 down-regulated) between GEO data and TCGA data. Based on these genes, we conducted our downstream analysis including functional enrichment analysis, protein-protein interaction, competing endogenous RNA (ceRNA) network and survival analysis. This study may provide more insight into the transcriptomic and functional features of LUSC through integrative analysis of GEO and TCGA data and suggests therapeutic targets and biomarkers for LUSC.

Long non-coding RNA FLVCR1-AS1 contributes to the proliferation and invasion of lung cancer by sponging miR-573 to upregulate the expression of E2F transcription factor 3

Lung cancer is one of the most common causes of cancer-related death all over the world. In recent years, long non-coding RNAs (lncRNAs) have been reported to play critical roles in the development and progression of human malignancies. In the present study, we aimed to study the role and mechanism of FLVCR1-AS1 in human non-small cell lung cancer (NSCLC). Results revealed that FLVCR1-AS1 was markedly upregulated in NSCLC tissues and cell lines. Knockdown of FLVCR1-AS1 significantly inhibited the proliferation, migration, invasion and promoted apoptosis of NSCLC cells, and suppressed tumor growth of NSCLC in vivo. Moreover, we explored regulatory mechanism, and found that FLVCR1-AS1 functioned as a competing endogenous RNA (ceRNA) by directly binding to miRNA-573, and E2F transcription factor 3 (E2F3) was identified as a down-stream target of miR-573. FLVCR1-AS1 positively regulated E2F3 expression through inhibiting miR-573 in NSCLC cells. Our findings suggested that FLVCR1-AS1/miR-573/E2F3 axis was an important signaling pathway in mediating tumorigenesis and progression of NSCLC, and further indicated that FLVCR1-AS1 could be a novel diagnostic biomarker and therapeutic target for NSCLC.

The long noncoding RNA SNHG1 regulates colorectal cancer cell growth through interactions with EZH2 and miR-154-5p

BACKGROUND

Mounting evidence demonstrates that long noncoding RNAs (lncRNAs) have critical roles during the initiation and progression of cancers. In this study, we report that the small nucleolar RNA host gene 1 (SNHG1) is involved in colorectal cancer progression.

METHODS

We analyzed RNA sequencing data to explore abnormally expressed lncRNAs in colorectal cancer. The effects of SNHG1 on colorectal cancer were investigated through in vitro and in vivo assays (i.e., CCK-8 assay, colony formation assay, flow cytometry assay, EdU assay, xenograft model, immunohistochemistry, and western blot). The mechanism of SNHG1 action was explored through bioinformatics, RNA fluorescence in situ hybridization, luciferase reporter assay, RNA pull-down assay, chromatin immunoprecipitation assay and RNA immunoprecipitation assay.

RESULTS

Our analysis revealed that SNHG1 was upregulated in human colorectal cancer tissues, and high SNHG1 expression was associated with reduced patient survival. We also found that high SNHG1 expression was partly induced by SP1. Moreover, SNHG1 knockdown significantly repressed colorectal cancer cells growth both in vitro and in vivo. Mechanistic investigations demonstrated that SNHG1 could directly interact with Polycomb Repressive Complex 2 (PRC2) and modulate the histone methylation of promoter of Kruppel like factor 2 (KLF2) and Cyclin dependent kinase inhibitor 2B (CDKN2B) in the nucleus. In the cytoplasm, SNHG1 acted as a sponge for miR-154-5p, reducing its ability to repress Cyclin D2 (CCND2) expression.

CONCLUSIONS

Taken together, the results of our studies illuminate how SNHG1 formed a regulatory network to confer an oncogenic function in colorectal cancer and suggest that SNHG1 may serve as a potential target for colorectal cancer diagnosis and treatment.

CircZNF609 promotes breast cancer cell growth, migration, and invasion by elevating p70S6K1 via sponging miR-145-5p

Background

Accumulating evidence suggests that circular RNAs (circRNAs) play critical roles in carcinomas. However, the contributions of circRNAs to breast cancer remain unclear. Herein, we determined the role of circZNF609 in breast cancer.

Methods

A total of 143 breast cancer and 38 normal tissues were collected to assess the expression of circZNF609 and its relationship with breast cancer prognosis. A series of in vitro and in vivo functional experiments were carried out to elucidate the role of circZNF609 in breast cancer progression and its underlying molecular mechanisms.

Results

CircZNF609 was markedly over-expressed in breast cancer tissues and cell lines, and high circZNF609 expression was closely associated with poor outcome. Silencing of circZNF609 inhibited the malignant phenotype of breast cancer in vitro and in vivo. Mechanistically, circ-ZNF609 served as a sponge of miR-145-5p to elevate p70S6K1 expression. Moreover, miR-145-5p overexpression or p70S6K1 knockdown abrogated the oncogenic effects of circZNF609 in breast cancer. In addition, clinically, a strong negative correlation was observed between the expression of circZNF609 and miR-145-5p in breast cancer tissues (r=–0.597, P<0.001), whereas a positive correlation between circZNF609 and p70S6K1 expression (r=0.319, P<0.001).

Conclusion

These data suggest that circZNF609 contributes to breast cancer progression, at least partly, by modulating the miR-145-5p/p70S6K1 axis, and it may be a potential therapeutic target for breast cancer.

Long noncoding RNA LINC00978 promotes cell proliferation and invasion in non‑small cell lung cancer by inhibiting miR‑6754‑5p

Long noncoding RNA LINC00978 has been reported to regulate the progression of several human types of cancer, including gastric and breast cancer. However, knowledge on LINC00978 in non‑small cell lung cancer (NSCLC) is limited. In the present study, it was demonstrated that LINC00978 expression was significantly upregulated in NSCLC tissues compared with the adjacent normal tissues. Furthermore, LINC00978 expression was positively correlated with the tumor, node and metastasis stage, and lymph node metastasis in NSCLC patients. Additionally, LINC00978 knockdown significantly inhibited the proliferation, migration and invasion of NSCLC cells while promoting cell apoptosis. In terms of the underlying mechanism, it was demonstrated that LINC00978 served as a competing endogenous RNA sponge for microRNA (miR)‑6754‑5p, which was downregulated in NSCLC tissues. The present study demonstrated that there was a negative correlation between LINC00978 and miR‑6754‑5p expression levels in NSCLC tissues. Additionally, it was demonstrated that inhibition of miR‑6754‑5p reversed the effects of LINC00978 knockdown on NSCLC cell proliferation, migration, invasion and apoptosis. In conclusion, results of the present study demonstrated that LINC00978 exerts an oncogenic role in NSCLC by inhibiting miR‑6754‑5p expression.

The putative tumour suppressor miR-1-3p modulates prostate cancer cell aggressiveness by repressing E2F5 and PFTK1

BACKGROUND

Previous studies report that miR-1-3p, a member of the microRNA-1 family (miR-1), and functions as a tumor suppressor in several different cancers. However, little is known regarding the biological role and intrinsic regulatory mechanisms of miR-1-3p in prostate cancer (PCa).

METHODS

In this study, the expression levels of miR-1-3p were first examined in PCa cell lines and tumor tissues by RT-qPCR and bioinformatics. The in vitro and in vivo functional effect of miR-1-3p was examined further. A luciferase reporter assay was conducted to confirm target associations.

RESULTS

We found that miR-1-3p was significantly downregulated in advanced PCa tissues and cell lines. Low miR-1-3p levels were strongly associated with aggressive clinicopathological features and poor prognosis in PCa patients. Ectopic expression of miR-1-3p in 22RV1 and LncaP cells was sufficient to prevent tumor cell growth and cell cycle progression in vitro and in vivo. Further mechanistic studies revealed that miR-1-3p could directly target the mRNA 3'- untranslated region (3'- UTR) of two central cell cycle genes, E2F5 and PFTK1, and could suppress their mRNA and protein expression. In addition, knockdown of E2F5 and PFTK1 mimicked the tumor-suppressive effects of miR-1-3p overexpression on PCa progression. Conversely, concomitant knockdown of miR-1-3p and E2F5 and PFTK1 substantially reversed the inhibitory effects of either E2F5 or PFTK1 silencing alone.

CONCLUSION

These data highlight an important role for miR-1-3p in the regulation of proliferation and cell cycle in the molecular etiology of PCa and indicate the potential for miR-1-3p in applications furthering PCa prognostics and therapeutics.

Long noncoding RNA Sox2 overlapping transcript (SOX2OT) promotes non-small-cell lung cancer migration and invasion via sponging microRNA 132 (miR-132)

Background

Long noncoding RNA (lncRNA) Sox2 overlapping transcript (SOX2OT) has been reported to be upregulated in various types of cancers, including non-small-cell lung cancer (NSCLC). However, the biological role and underlying mechanism of SOX2OT activity in NSCLC remain largely unknown. This study aims to investigate the function and possible molecular mechanisms of SOX2OT in NSCLC.

Materials and methods

Quantitative real-time polymerase chain reaction was used to detect SOX2OT expression, and cellular proliferation, migration, and invasion were measured using cell counting kit-8, wound healing, and Transwell invasion assays, respectively. Western blotting was used to determine protein expression. Starbase 2.0 and luciferase reporter assay were utilized to identify the molecular target of SOX2OT.

Results

Here, we discovered that SOX2OT was markedly upregulated in NSCLC tissues and cell lines. Knockdown of SOX2OT inhibited the proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT) process in NSCLC cells. Moreover, we explored the regulatory mechanism of SOX2OT and found that SOX2OT directly bound microRNA 132 (miR-132) in NSCLC cells. Importantly, miR-132 inhibition partially reversed the SOX2OT knockdown-mediated inhibitory effect on cell proliferation, migration, invasion, and EMT process. We also found that SOX2OT could regulate zinc finger E-box-binding homeobox 2 (a target of miR-132) expression, which played crucial roles in tumor cell proliferation and invasion.

Conclusion

These findings indicated that SOX2OT was a noncoding oncogene that exerted important regulatory functions in NSCLC via sponging miR-132 and might represent a novel strategy for overcoming this disease.

A Plasma Long Noncoding RNA Signature for Early Detection of Lung Cancer

The early detection of lung cancer is a major clinical challenge. Long noncoding RNAs (lncRNAs) have important functions in tumorigenesis. Plasma lncRNAs directly released from primary tumors or the circulating cancer cells might provide cell-free cancer biomarkers. The objective of this study was to investigate whether the lncRNAs could be used as plasma biomarkers for early-stage lung cancer. By using droplet digital polymerase chain reaction, we determined the diagnostic performance of 26 lung cancer–associated lncRNAs in plasma of a development cohort of 63 lung cancer patients and 33 cancer-free individuals, and a validation cohort of 39 lung cancer patients and 28 controls. In the development cohort, 7 of the 26 lncRNAs were reliably measured in plasma. Two (SNHG1 and RMRP) displayed a considerably high plasma level in lung cancer patients vs. cancer-free controls (all P < .001). Combined use of the plasma lncRNAs as a biomarker signature produced 84.13% sensitivity and 87.88% specificity for diagnosis of lung cancer, independent of stage and histological type of lung tumor, and patients' age and sex (all P > .05). The diagnostic value of the plasma lncRNA signature for lung cancer early detection was confirmed in the validation cohort. The plasma lncRNA signature may provide a potential blood-based assay for diagnosing lung cancer at the early stage. Nevertheless, a prospective study is warranted to validate its clinical value.

The Prognostic Value of Expression of the Long Noncoding RNA (lncRNA) Small Nucleolar RNA Host Gene 1 (SNHG1) in Patients with Solid Malignant Tumors: A Systematic Review and Meta-Analysis

BACKGROUND The long non-coding RNA (lncRNA) small nucleolar RNA host gene 1 (SNHG1) is expressed in solid malignant tumors. The aim of this systematic review and meta-analysis was to determine whether expression of the lncRNA SNHG1 was associated with prognosis in patients with malignancy. MATERIAL AND METHODS A literature review from Jan 1970 to July 2018 identified publications in the English language. Databases searched included: PubMed, OVID, Web of Science, the Cochrane Database, Embase, EBSCO, Google Scholar. Systematic review and meta-analysis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The Newcastle-Ottawa Scale (NOS) assessment tool for risk of bias was used. RESULTS Eight publications (570 patients) and eight solid tumors were identified, including osteosarcoma, colorectal cancer, hepatocellular carcinoma, non-small cell lung cancer, esophageal cancer, ovarian cancer, glioma, and gastric cancer. Meta-analysis showed that expression of the lncRNA SNHG1 was significantly correlated with reduced overall survival (OS) (HR=1.917; 95% CI, 1.58-2.31) (P<0.001). Subgroup analysis showed that lncRNA SNHG1 expression was significantly correlated with TNM stage (OR=3.99; 95% CI, 2.48-6.43) and lymph node metastasis (OR=3.12; 95% CI, 1.95-4.98). There were no significant correlations between lncRNA SNHG1 expression and patient gender, tumor subtype, or tumor size. CONCLUSIONS Systematic literature review and meta-analysis identified eight publications that included 570 patients with eight types of solid malignant tumor, and showed that the expression of the lncRNA SNHG1 was significantly associated with worse clinical outcome.

Small nucleolar RNA host gene 1: A new biomarker and therapeutic target for cancers

OBJECTIVES

Long non-coding RNAs (lncRNAs), a group of transcripts with length greater than 200 nucleotides, have been involved in multiple pathophysiological processes of the human body, especially in tumorigenesis and progression of cancers. The aberrant expression of lncRNAs processes crucial functions involved in proliferation, apoptosis and metastatic capacity of cancers. Recent studies have revealed that small nucleolar RNA host gene 1 (SNHG1), a long non-coding RNA transcribed from UHG, was located in chromosome 11. Aberrant expression of SNHG1 has been demonstrated to be associated with various sites of cancers such as glioma, esophageal cancer, gastric cancer and many others, and its deregulation could be related to survival and prognosis of cancer patients. Pertinent to clinical practice, SNHG1 might act as a prognostic biomarker for tumors and might even serve as potential target for therapy. In this review, we summarized current researches concerning the role of SNHG1 in tumor progression and discussed its mechanisms involved.

MATERIALS AND METHODS

In this review, we summarized and figured out recent studies concerning the expression and biological mechanisms of SNHG1in tumor development. The related studies were obtained through a systematic search of PubMed, Embase and Cochrane Library.

RESULTS

SNHG1 was a valuable cancer-related lncRNA that the expression level was up-regulation in a variety of malignancies, including glioma, esophageal cancer, lung cancer, gastric cancer, hepatocellular carcinoma, colorectal carcinoma, prostate cancer, cervical cancer, osteosarcoma, neuroblastoma, nasopharyngeal carcinoma. The aberrant expressions of SNHG1 have shown to contribute to proliferation, migration, and invasion of cancer cells.

CONCLUSIONS

SNHG1 represents promising novel biomarkers for various cancer types and have a great potential to be effectively used in clinical practice in the near future.

Long non-coding RNA CASC15 promotes tongue squamous carcinoma progression through targeting miR-33a-5p

Long non-coding RNAs (lncRNAs) have gained a lot of attention because they participate in several human disorders, including tumors. This study determined the role of LncRNA CASC15 (cancer susceptibility candidate 15) in the development of tongue squamous cell carcinoma (TSCC). Here, we identified that CASC15 expression was upregulated in TSCC samples and cell lines. We showed that overexpression of CASC15 promoted cell proliferation, cycle, and migration in TSCC. In addition, we revealed that miR-33a-5p expression was downregulated in TSCC tissues and cell lines. Moreover, we showed that the expression of CASC15 was negatively related with miR-33a-5p expression in TSCC tissues. Ectopic expression of miR-33a-5p suppressed cell proliferation, cycle, and migration in TSCC. Elevated expression of CASC15 suppressed miR-33a-5p expression and promoted ZEB1 expression in SCC4 cell. Ectopic expression of CASC15 promoted TSCC cell proliferation, cycle, and migration through targeting miR-33a-5p. These results suggested that lncRNA CASC15 and miR-33a-5p might be exploited as new markers of TSCC and were potential treatment targets for TSCC patients.

Long Noncoding RNA SNHG1 Promotes Neuroinflammation in Parkinson's Disease via Regulating miR-7/NLRP3 Pathway

Parkinson's disease (PD) is the second most common neurodegenerative disorders. Neuroinflammation plays an important role in the pathogenesis of PD. Long noncoding RNA small nucleolar RNA host gene 1 (SNHG1) was elevated in the brain specimens of PD patients and MPP+-treated SH-SY5Y cells. The expression of mouse Snhg1 and miR-7 was firstly determined in lipopolysaccharide (LPS)-induced BV2 cells. The role and mechanism of SNHG1 in the neuroinflammation of PD were investigated using gain- and loss-of function approaches both in vitro and in vivo. Snhg1 expression was elevated, whereas miR-7 reduced in LPS-induced BV2 cells. Upregulation of Snhg1 elevated, and Snhg1 knockdown suppressed LPS-induced BV2 microglial activation and inflammation. miR-7 reversed, while anti-miR-7 further enhanced the effects of Snhg1 on BV2 cells. Furthermore, we found that Snhg1 functioned as a competing endogenous RNA for miR-7 to regulate nod-like receptor protein 3 (NLRP3) expression, leading to the activation of NLRP3 inflammasome. In the microglial culture supernatant transfer model, knockdown of Snhg1 or NLRP3 in LPS-stimulated BV2 cells inhibited primary neurons from apoptosis and elevated caspase-3 activity. Additionally, Snhg1 was increased in MPTP-induced PD mouse models. Downregulation of Snhg1 elevated miR-7 expression, suppressed the activation of microglia and NLRP3 inflammasome as well as dopaminergic neuron loss in the midbrain substantia nigra pars compacta in MPTP-treated mice. In conclusion, our study suggests that SNHG1 promotes neuroinflammation in the pathogenesis of PD via modulating miR-7/NLRP3 pathway.