Expression of Long Non-Coding RNA (lncRNA) Small Nucleolar RNA Host Gene 1 (SNHG1) Exacerbates Hepatocellular Carcinoma Through Suppressing miR-195

Functional role of lncRNAs in gastrointestinal malignancies: the peculiar case of small nucleolar RNA host gene family

Long noncoding RNAs (lncRNAs) play crucial roles in normal physiology and are often de-regulated in disease states such as cancer. Recently, a class of lncRNAs referred to as the small nucleolar RNA host gene (SNHG) family have emerged as important players in tumourigenesis. Here, we discuss new findings describing the role of SNHGs in gastrointestinal tumours and summarize the three main functions by which these lncRNAs promote carcinogenesis, namely: competing with endogenous RNAs, modulating protein function, and regulating epigenetic marking. Furthermore, we discuss how SNHGs participate in different hallmarks of cancer, and how this class of lncRNAs may serve as potential biomarkers in cancer diagnosis and therapy.

Tumorigenesis of basal muscle invasive bladder cancer was mediated by PTEN protein degradation resulting from SNHG1 upregulation

BACKGROUND

Phosphatase and tensin homolog deleted on chromosome ten (PTEN) serves as a powerful tumor suppressor, and has been found to be downregulated in human bladder cancer (BC) tissues. Despite this observation, the mechanisms contributing to PTEN's downregulation have remained elusive.

METHODS

We established targeted genes' knockdown or overexpressed cell lines to explore the mechanism how it drove the malignant transformation of urothelial cells or promoted anchorageindependent growth of human basal muscle invasive BC (BMIBC) cells. The mice model was used to validate the conclusion in vivo. The important findings were also extended to human studies.

RESULTS

In this study, we discovered that mice exposed to N-butyl-N-(4-hydroxybu-tyl)nitrosamine (BBN), a specific bladder chemical carcinogen, exhibited primary BMIBC accompanied by a pronounced reduction in PTEN protein expression in vivo. Utilizing a lncRNA deep sequencing high-throughput platform, along with gain- and loss-of-function analyses, we identified small nucleolar RNA host gene 1 (SNHG1) as a critical lncRNA that might drive the formation of primary BMIBCs in BBN-treated mice. Cell culture results further demonstrated that BBN exposure significantly induced SNHG1 in normal human bladder urothelial cell UROtsa. Notably, the ectopic expression of SNHG1 alone was sufficient to induce malignant transformation in human urothelial cells, while SNHG1 knockdown effectively inhibited anchorage-independent growth of human BMIBCs. Our detailed investigation revealed that SNHG1 overexpression led to PTEN protein degradation through its direct interaction with HUR. This interaction reduced HUR binding to ubiquitin-specific peptidase 8 (USP8) mRNA, causing degradation of USP8 mRNA and a subsequent decrease in USP8 protein expression. The downregulation of USP8, in turn, increased PTEN polyubiquitination and degradation, culminating in cell malignant transformation and BMIBC anchorageindependent growth. In vivo studies confirmed the downregulation of PTEN and USP8, as well as their positive correlations in both BBN-treated mouse bladder urothelium and tumor tissues of bladder cancer in nude mice.

CONCLUSIONS

Our findings, for the first time, demonstrate that overexpressed SNHG1 competes with USP8 for binding to HUR. This competition attenuates USP8 mRNA stability and protein expression, leading to PTEN protein degradation, consequently, this process drives urothelial cell malignant transformation and fosters BMIBC growth and primary BMIBC formation.

The long non-coding RNA SNHG1 attenuates chondrocyte apoptosis and inflammation via the miR-195/IKK-α axis

Multiple studies have suggested that long non-coding RNAs (lncRNAs) are involved in the development and progression of osteoarthritis (OA). However, how lncRNA SNHG1 regulates OA remains unknown. This study aimed to explore how SNHG1 regulates chondrocyte apoptosis and inflammation. Our data showed that H₂O₂-treated chondrocytes exhibited lower expression of SNHG1 and secreted higher levels of IL-6, IL-8, and TNF-α than untreated cells. Further, overexpressing SNHG1 reduced chondrocyte apoptosis and production of inflammatory factors. Additionally, SNHG1 targets miR-195 directly, and IKK-α has direct biding sites for miR-195. Of note, IKK-α acts as an inhibitor of the NF-κB signaling pathway. These findings suggest that SNHG1 can upregulate IKK-α by inhibiting miR-195 and thus, inhibit NF-κB activity. Our in vivo experiments validate our in vitro findings. Thus, under oxidative stress, SNHG1 inhibits the activation of NF-κB to attenuate chondrocyte apoptosis and inflammation via the miR-195/IKK-α axis. Targeting SNHG1 may serve as a potential novel therapeutic approach for OA.

Identification of m6A-Related lncRNA to Predict the Prognosis of Patients with Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. In the past decades, HCC treatment has achieved great progress; however, the overall prognosis remains poor. Therefore, it is the need of the hour to identify new prognostic biomarkers which can advance our understanding related to the underlying molecular mechanism of adverse prognosis and apply them to clinical work in prognosis prediction. In the present study, data of 576 HCC patients and 292 normal control cases from TCGA and ICGC databases were enrolled to our bioinformatic analysis. SNHG1 and SNHG3 were identified as overlapping genes in TCGA and ICGC databases using Pearson correlation analysis and univariate Cox regression analysis. Further, we used the median of the SNHG1 and SNHG3 expression values as the cutoff values to define the HCC patient groups with high or low expression level. The subsequent analysis revealed that abnormal high expression of SNHG1 or SNHG3 affected the immune infiltration patterns and the crosstalk among immune cells. Moreover, high expression of SNHG1 or SNHG3 resulted in drug resistant to AKT inhibitor VII, bexarotene, bicalutamide, dasatinib, erlotinib, and gefitinib. In addition, lower tumor neoantigen burden was observed in high SNHG1 or SNHG3 group. Further, we found significant relation between the aberrant upregulation of SNHG1 and SNHG3 in tumor grade and stage. We established a nomogram to systematically predict the 5- and 8-year overall survival of liver cancer patients with good accuracy. Finally, the in vitro assays suggest that SNHG1 and SNHG3 promote the proliferative, migratory, and invasive abilities of HCC cells.

lncRNA GHET1 Promotes the Progression of Triple-Negative Breast Cancer via Regulation of miR-377-3p/GRSF1 Signaling Axis

Objective

This study is aimed at investigating the role of lncRNA GHET1 in the progression of triple-negative breast cancer (TNBC).

Methods

Tumor tissues and paracancerous tissues (normal) of TNBC patients were collected. Human normal breast cells (MCF10A) and TNBC cells (MDA-MB-468 and HCC1937) were employed for in vitro analysis. The expression of lncRNA GHET1, miR-377-3p, and GRSF1 was detected by qRT-PCR. The lncRNA GHET1 and miR-377-3p were overexpressed or knocked down in the TNBC cells, respectively. To determine the specific biological activities of the TNBC cells, MTT, flow cytometry, and wound healing assay were adopted to evaluate the cellular proliferation, apoptosis, and migration abilities, respectively. MMP-9 and MMP-2 protein expression levels were detected as well by Western blot in the cells. The relationship between miR-377-3p and lncRNA GHET1, miR-377-3p, and GRSF1 was validated using dual-luciferase reporter assay.

Results

lncRNA GHET1 was significantly upregulated in the TNBC patients' tissues and the TNBC cell lines. Overexpression of lncRNA GHET1 significantly increased the proliferation and migration ability, but decreased apoptosis in the TNBC cells. Additionally, overexpression of lncRNA GHET1 upregulated both MMP-9 and MMP-2 protein expression levels. Correlation analysis found that miR-377-3p had a positive relationship with GRSF1, but had a negative relationship with lncRNA GHET1. miR-377-3p mimic attenuated the effects of lncRNA GHET1 on cellular proliferation, apoptosis, and migration of the TNBC cells.

Conclusion

lncRNA GHET1 promotes TNBC progression through the miR-377-3p/GRSF1 signaling axis.

Long non-coding RNA small nucleolar RNA host genes: functions and mechanisms in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors of the digestive system, with a high degree of malignancy. Although treatment methods are constantly improving, the mortality of patients is still very high, and the small nucleolar RNA host gene (SNHG) plays an important role in the occurrence and development of cancer. It can activate downstream signaling molecules by acting on microRNA and microRNA target genes, promote the proliferation, invasion, and migration of HCC cells, and provide a new molecular target for the treatment of HCC. At present, the molecular mechanisms of HCC remain unclear. In this study, the mechanism and signaling pathway of SNHG in HCC are reviewed, which provides a theoretical basis for the clinical treatment of HCC.

Growth arrest-specific 5 lncRNA as a valuable biomarker of chemoresistance in osteosarcoma

Osteosarcoma is the most common primary malignant bone tumour in children and teenagers, and it is characterised by drug resistance and high metastatic potential. Increasing studies have highlighted the critical roles of long noncoding RNAs (lncRNAs) as oncogenes or tumour suppressors as well as new biomarkers and therapeutic targets in osteosarcoma. The growth arrestspecific 5 (GAS5) lncRNA can function as a tumour suppressor in several cancers. The present study aimed to validate GAS5 and other chemoresistanceassociated lncRNAs as biomarkers in a cohort of primary osteosarcoma samples, to obtain predictive information on resistance or sensitivity to treatment. The GAS5 and a panel of lncRNAs related to chemoresistance [SNGH1, FOXD2-AS1, deleted in lymphocytic leukemia (DLEU2) and LINC00963] were evaluated in a cohort of osteosarcoma patients enrolled at the Careggi University Hospital. Total RNA was extracted from formalin-fixed paraffin-embedded (FFPE) tissue sections and the expression levels of the lncRNAs were quantified by qPCR. A bioinformatic analysis on deposited RNA-seq data was performed to validate the qPCR results. Clustering analysis shows that GAS5 could be linked to the expression of isoforms 02 and 04 of the lncRNA DLEU2, whereas the DLEU2 isoform 08 is linked to the lncRNA LINC00963. We found that GAS5 is significantly increased in patients with a good prognosis and is expressed differently between chemosensitive and chemoresistant osteosarcoma patients. However, the results obtained are not concordant with the in-silico analysis performed on the TARGET osteosarcoma dataset. In the future, we would enlarge the case series, including different disease settings.

Positive feedback loop of lncRNA SNHG1/miR‑16‑5p/GATA4 in the regulation of hypoxia/reoxygenation‑induced cardiomyocyte injury

Numerous studies have demonstrated that long non-coding RNAs (lncRNAs) serve an important regulatory role in ischemic injury of cardiomyocytes. lncRNA small nucleolar RNA host gene 1 (SNHG1) could effectively protect cardiomyocytes against various injuries. However, the role of SNHG1 in ischemic cardiomyocyte injury is unclear. It was hypothesized that SNHG1 may have a protective effect on cardiomyocyte injury induced by hypoxia/reoxygenation (H/R) by sponging microRNA (miRNA/miR). The purpose of the present study was to explore the role and molecular mechanism of SNHG1 in ischemic cardiomyocyte injury. A H9c2 cardiomyocyte H/R model was established. The expression levels of SNHG1 in cardiomyocytes treated with H/R were detected using reverse transcription-quantitative PCR. A luciferase reporter assay was used to analyze the associations among SNHG1, miR-16-5p and GATA binding protein 4 (GATA4). Chromatin immunoprecipitation experiments were performed to analyze the interaction between SNHG1 and GATA4. Cell Counting Kit-8, enzyme-linked immunosorbent assay, terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling and western blotting experiments were used to detect cell activity, lactate dehydrogenase release, apoptosis and apoptosis-related proteins (Bcl-2, Bax, Cleaved caspase-3 and Cleaved caspase-9), respectively. The expression levels of SNHG1 were downregulated in cardiomyocytes treated with H/R. Overexpression of SNHG1 had a protective effect on cardiomyocyte injury induced by H/R. In addition, SNHG1 could regulate the expression levels of GATA4 via sponging of miR-16-5p. Further experiments revealed that GATA4 could bind to the promoter region of SNHG1 and subsequently regulated the expression levels of SNHG1, indicating the important role of the positive feedback loop of SNHG1/miR-16-5p/GATA4 in cardiomyocyte ischemic injury. To conclude, the present study revealed the protective effect of the SNHG1/miR-16-5p/GATA4 positive feedback loop on cardiomyocyte injury induced by H/R and provided a potential therapeutic target for ischemic cardiomyocyte injury.

Long Noncoding RNA SNHG1 Regulates LMNB2 Expression by Sponging miR-326 and Promotes Cancer Growth in Hepatocellular Carcinoma

OBJECTIVE

The purpose of the study is to explore the potential competing endogenous RNA (ceRNA) network and investigate the molecular mechanism of long noncoding RNA (lncRNA) small nucleolar RNA host gene 1 (SNHG1) in hepatocellular carcinoma (HCC) development.

METHODS

By analyzing the data of HCC in The Cancer Genome Atlas (TCGA) database, we included differentially expressed lncRNA and microRNA (miRNA) profiles and constructed ceRNA networks related to the prognosis of HCC patients. qRT-PCR, Western blotting, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), transwell assay, and the nude mouse model were employed to test the effects of SNHG1 and LMNB2 on tumor proliferation and growth in vitro and in vivo.

RESULTS

In the study, we identified 115 messenger RNAs (mRNAs), 12 lncRNAs, and 37 miRNAs by intersecting differentially expressed genes (DEGs) in TCGA and StarBase databases. Then, SNHG1-miR-326-LMNB2 pathway came into notice after further survival analysis and hub gene screening. Our results showed that SNHG1 expression was upregulated significantly in HCC tissues and cell lines. Downregulation of both LMNB2, the target of miR-326 in HCC, and SNHG1 inhibited tumor proliferation and growth in vitro and in vivo. Furthermore, SNHG1 could regulate LMNB2 expression through binding to miR-326 in HCC cell lines.

CONCLUSION

SNHG1 is a promising prognostic factor in HCC, and the SNHG1-miR-326-LMNB2 axis may be a potential therapeutic target for HCC.

Retracted: Expression of Long Non-Coding RNA (lncRNA) Small Nucleolar RNA Host Gene 1 (SNHG1) Exacerbates Hepatocellular Carcinoma Through Suppressing miR-195

Retracted, due to breach of publishing guidelines, following the identification of non-original and manipulated figure images. Reference: Hui Zhang, Dong Zhou, Mingang Ying, Minyong Chen, Peng Chen, Zhaoshuo Chen, Fan Zhang: Expression of Long Non-Coding RNA (lncRNA) Small Nucleolar RNA Host Gene 1 (SNHG1) Exacerbates Hepatocellular Carcinoma Through Suppressing miR-195. Med Sci Monit, 2016; 22: 4820-4829. DOI: 10.12659/MSM.898574.

High expression of lncRNA SNHG1 in prostate cancer patients and inhibition of SNHG1 suppresses cell proliferation and promotes apoptosis

Objective

This study aimed to investigate the expression of long non-coding RNA (lncRNA) small nucleolar RNA host gene 1 (SNHG1) in prostate cancer (PCa) patients and to assess the effects of SNHG1 on PCa cell proliferation and apoptosis.

Materials and Methods

A total of 134 PCa patients were randomly included from patients who underwent surgical resection at our hospital from October 2015 to December 2016. The SNHG1 expression levels in PCa tissues and paired adjacent non-cancerous tissues were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The association of the SNHG1 expression with clinical-pathological features of PCa patients was summarized and evaluated. A short interfering (si) RNA targeting SNHG1 and pcDNA3.1-SNHG1 were transfected into PC3 and DU145 PCa cell lines, and transfection efficiency was verified by qRT-PCR. Cell proliferation and apoptosis were assessed by methylthiazolyldiphenyl-tetrazolium bromide (MTT) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays, respectively.

Results

The SNHG1 expression was significantly upregulated in PCa tumor tissues compared with paired adjacent non-cancerous tissues. The SNHG1 expression was obviously associated with the TNM stage, Gleason Score, lymph node invasion, and long-term metastasis mortality rate. Silencing of SNHG1 inhibited cell proliferation and promoted apoptosis in PC3 and DU145 PCa cell lines in vitro, while overexpression of SNHG1 led to opposite results.

Conclusion

LncRNA SNHG1 was upregulated and associated with aggressive malignant behavior in PCa progression. SNHG1 might serve as a potential prognostic biomarker and potential therapeutic target for PCa.

Early detection of hepatocellular carcinoma via liquid biopsy: panel of small extracellular vesicle-derived long noncoding RNAs identified as markers

This study investigated the diagnostic potential of serum small extracellular vesicle‐derived long noncoding RNAs (EV‐lncRNAs) for hepatocellular carcinoma (HCC). Driver oncogenic lncRNA candidates were selected by a comparative analysis of lncRNA expression profiles from two whole transcriptome human HCC datasets (Catholic_LIHC and TCGA_LIHC). Expression of selected lncRNAs in serum and small EVs was evaluated using quantitative reverse transcription PCR. Diagnostic power of serum EV‐lncRNAs for HCC was determined in the test (n = 44) and validation (n = 139) cohorts. Of the six promising driver onco‐lncRNAs, DLEU2, HOTTIP, MALAT1, and SNHG1 exhibited favorable performance in the test cohort. In the validation cohort, serum EV‐MALAT1 displayed excellent discriminant ability, while EV‐DLEU2, EV‐HOTTIP, and EV‐SNHG1 showed good discriminant ability between HCC and non‐HCC. Furthermore, a panel combining EV‐MALAT1 and EV‐SNHG1 achieved the best area under the curve (AUC; 0.899, 95% CI = 0.816–0.982) for very early HCC, whereas a panel with EV‐DLEU2 and alpha‐fetoprotein exhibited the best positivity (96%) in very early HCC. Serum small EV‐MALAT1, EV‐DLEU2, EV‐HOTTIP, and EV‐SNHG1 may represent promising diagnostic markers for very early‐stage HCC.

Targeting Long Non-Coding RNAs in Hepatocellular Carcinoma: Progress and Prospects

Hepatocellular carcinoma is the fifth-ranked cancer worldwide with a relatively low five-year survival rate. Long non-coding RNAs are a group of RNAs with remarkable aberrant expression which could act on multiple bioprocesses and ultimately impact upon tumor proliferation, invasion, migration, metastasis, apoptosis, and therapy resistance in cancer cells including hepatocellular carcinoma cells. In recent years, long non-coding RNAs have been reported to be indispensable targets in clinical target therapy to stop the growth of cancer and prolong the lifespan of patients with hepatocellular carcinoma. In this review, we enumerate the signaling pathways and life activities affected by long non-coding RNAs in hepatocellular carcinoma cells to illustrate the role of long non-coding RNAs in the development and therapy resistance of hepatocellular carcinoma.

Long non-coding RNA SNHG1 suppresses cell migration and invasion and upregulates SOCS2 in human gastric carcinoma

Gastric carcinoma (GC) is one of the most common malignancies and the third leading cause of cancer-related deaths worldwide. Long noncoding RNAs (lncRNAs) may be an important class of functional regulators involved in human gastric cancers development. In this study, we investigated the clinical significance and function of lncRNA SNHG1 in GC. SNHG1 was significantly downregulated in GC tumor tissues compared with adjacent noncancerous tissues. Overexpression of SNHG1 in BGC-823 cells remarkably inhibited not only cell proliferation, migration, invasion in vitro, but also tumorigenesis and lung metastasis in the chick embryo chorioallantoic membrane (CAM) assay in vivo. Conversely, inhibition of SNHG1 by transfection of siRNA in AGS cells resulted in opposite phenotype changes. Mechanically, SNHG1 was found interacted with ILF3, NONO and SFPQ. RNA-seq combined with bioinformatic analysis identified a serial of downstream genes of SNHG1, including SOCS2, LOXL2, LTBP3, LTBP4. Overexpression of SNHG1 induced SOCS2 expression whereas knockdown of SNHG1 decreased SOCS2 expression. In addition, knockdown of SNHG1 promoted the activation of JAK2/STAT signaling pathway. Taken together, our data suggested that SNHG1 suppressed aggressive phenotype of GC cells and regulated SOCS2/JAK2/STAT pathway.

•

SNHG1 was significantly downregulated in GC tumor tissues.

•

SNHG1 suppressed proliferation and migration of GC cells.

•

SNHG1 localized in nucleus of GC cells and interacted with ILF3, NONO and SFPQ.

•

SNHG1 regulate SOCS2 expression in GC cell lines and JAK2/STAT signaling pathway in AGS cells.

LINC00922 promotes the proliferation, migration, invasion and EMT process of liver cancer cells by regulating miR-424-5p/ARK5

AMPK-related protein kinase 5 (ARK5) promotes the deterioration of hepatocellular carcinoma (HCC). From the perspective of lncRNA-miRNA-mRNA, this study explored in-depth the intervention mechanism of ARK5. The binding relationship between miR-424-5p and two genes (LINC00922 and ARK5) were analyzed by Bioinformatics and dual-luciferase experiments. After clinical sample collection, the expressions of miR-424-5p, LINC00922 and ARK5 in HCC tissues were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). The correlation between LINC00922, miR-424-5p, and ARK5 in HCC tissues was analyzed by Pearson correlation. The influences of miR-424-5p, LINC00922 and ARK5 on the basic functions (viability, migration and invasion) of cancer cells were detected by cell counting kit-8, wound healing, and Transwell experiments, and their regulatory effects on related genes, as well as their relationship, were tested by qRT-PCR and Western blot. MiR-424-5p was low expressed, whereas LINC00922 and ARK5 were high expressed in HCC tissues. MiR-424-5p was negatively associated with LINC00922 and ARK5 that was positively associated with LINC00922. Interestingly, LINC00922 partially shared an identical binding site of miR-424-5p with ARK5. LINC00922 its overexpression partially offset the inhibitory effect of miR-424-5p on cancer cell functions. ARK5 silencing repressed the malignant phenotype of cancer cells and inhibited the expressions of epithelial-to-mesenchymal transition (EMT)-related molecules (Vimentin, Snail and N-Cadherin). However, these effects were partially neutralized by miR-424-5p inhibitors. LINC00922 increases the cell viability, migration, invasion and EMT process of HCC cells by regulating the miR-424-5p/ARK5 axis, and thus may serve as a potential target for targeted therapy.

The Impact of Long Non-Coding RNAs in the Pathogenesis of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is among the utmost deadly human malignancies. This type of cancer has been associated with several environmental, viral, and lifestyle risk factors. Among the epigenetic factors which contribute in the pathogenesis of HCC is dysregulation of long non-coding RNAs (lncRNAs). These transcripts modulate expression of several tumor suppressor genes and oncogenes and alter the activity of cancer-related signaling axes. Several lncRNAs such as NEAT1, MALAT1, ANRIL, and SNHG1 have been up-regulated in HCC samples. On the other hand, a number of so-called tumor suppressor lncRNAs namely CASS2 and MEG3 are down-regulated in HCC. The interaction between lncRNAs and miRNAs regulate expression of a number of mRNA coding genes which are involved in the pathogenesis of HCC. H19/miR-15b/CDC42, H19/miR-326/TWIST1, NEAT1/miR-485/STAT3, MALAT1/miR-124-3p/Slug, MALAT1/miR-195/EGFR, MALAT1/miR-22/SNAI1, and ANRIL/miR-144/PBX3 axes are among functional axes in the pathobiology of HCC. Some genetic polymorphisms within non-coding regions of the genome have been associated with risk of HCC in certain populations. In the current paper, we describe the recent finding about the impact of lncRNAs in HCC.

SNHG1 knockdown upregulates miR-376a and downregulates FOXK1/Snail axis to prevent tumor growth and metastasis in HCC

Long non-coding RNAs (lncRNAs), microRNAs (miRNAs or miRs), and genes are emerging players in cancer progression. In the present study, we explored the roles and interactions of oncogenic lncRNA small nucleolar RNA host gene 1 (SNHG1), miR-376, forkhead box protein K1 (FOXK1), and Snail in hepatocellular carcinoma (HCC). Expression of SNHG1, miR-376, and FOXK1 in HCC was characterized in clinical HCC tissues of 75 patients with HCC. The interactions between SNHG1 and miR-376 and between miR-376 and FOXK1 were predicted and confirmed by dual-luciferase reporter gene and RNA immunoprecipitation assays. Overexpression and knockdown experiments were performed in HCC cells to examine the effects of the SNHG1/miR-376/FOXK1/Snail axis on viability, apoptosis, invasiveness, and migrating abilities. Their effects on tumor growth and metastasis were validated in nude mouse models. SNHG1 and FOXK1 were upregulated, and miR-376a was downregulated in HCC. SNHG1 knockdown contributed to suppression of HCC cell viability, invasion, and migration properties and promotion of apoptosis. SNHG1 could competitively bind to miR-376a to upregulate its target gene FOXK1, which upregulated Snail. SNHG1 knockdown delayed cancer progression both in vitro and in vivo by upregulating miR-376a and downregulating FOXK1 and Snail. SNHG1 knockdown exerts anti-tumor activity in HCC, suggesting a therapeutic target.

Downregulated microRNA-129-5p by Long Non-coding RNA NEAT1 Upregulates PEG3 Expression to Aggravate Non-alcoholic Steatohepatitis

Long non-coding RNAs (lncRNAs) have recently emerged as inflammation-associated biological molecules with a specific role in the progression of liver fibrosis conditions including non-alcoholic steatohepatitis (NASH). The aim of this study was to elucidate the effects of lncRNA nuclear enriched abundant transcript 1 (NEAT1), microRNA-129-5p (miR-129-5p), and paternally expressed gene 3 (PEG3) on the biological activities of hepatic stellate cells (HSCs) subjected to NASH. First, microarray-based analysis revealed upregulated PEG3 in NASH. Liver tissues from mice fed a methionine–choline-deficient (MCD) diet exhibited increased expression of NEAT1 and PEG3 along with lower miR-129-5p expression. A series of in vitro and in vivo assays were then performed on HSCs after transfection with shPEG3, miR-129-5p mimic, or treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of the nuclear factor-kappa B (NF-κB) signaling pathway. Results confirmed the alleviated fibrosis by restoring miR-129-5p, while depleting PEG3 or NEAT1, as evidenced by the inactivation of HSCs. To sum up, NEAT1 can bind specifically to miR-129-5p and consequently regulate miR-129-5p and PEG3 expression in relation to the HSC activation occurring in NASH. Thus, NEAT1-targeted inhibition against miR-129-5p presents a promising therapeutic strategy for the treatment of NASH.

Long noncoding RNA SNHG1 promotes human prostate cancer progression by sponging miR-383-5p

Prostate cancer is the most common urinary malignancy in males. Long noncoding RNA small nucleolar RNA host gene 1 (lncRNA SNHG1) has been reported to play a crucial role in the development of various cancers. However, the understanding of SNHG1 in prostate cancer is still limited and needs further investigation. In this study, we found the level of SNHG1 was significantly upregulated in prostate cancer tissues and cells. Knockdown of SNHG1 significantly suppressed proliferation, migration and invasion and promoted cell apoptosis in prostate cancer cells. In addition, knockdown of SNHG1 significantly downregulated proliferating cell nuclear antigen and upregulated cleaved caspase-3. MiR-383-5p was identified to be a target of SNHG1 by bioinformatics analysis, dual-luciferase reporter assay, RNA immunoprecipitation assay and RNA pull-down assay. MiR-383-5p was significantly downregulated in prostate cancer tissues and cells. Inhibition of miR-383-5p could partially restore the effects of SNHG1 knockdown on prostate cancer cell proliferation, apoptosis, migration and invasion. Furthermore, murine xenograft models were established to investigate the effects of SNHG1 and miR-383-5p in tumorigenesis in vivo. We found SNHG1 knockdown or miR-383-5p overexpression repressed tumor growth in vivo. In conclusion, SNHG1 contributed to prostate cancer progression by targeting miR-383-5p, elucidating that SNHG1 might be a target for prostate cancer therapy.

Dysregulation of lnc-SNHG1 and miR-216b-5p correlate with chemoresistance and indicate poor prognosis of serous epithelial ovarian cancer

Aim

This study aimed to explore whether the dysregulation of lnc-small nucleolar RNA host gene 1 (SNHG1) and miR-216b-5p correlated with chemoresistance and indicated poor prognosis of serous epithelial ovarian cancer (EOC).

Methods and results

The expression of lnc-SNHG1 was upregulated, while miR-216b-5p showed low expression in patients with chemoresistant EOC compared with patients with chemosensitive EOC. The multivariate Cox regression analysis showed that the expression of miR-216b-5p and FIGO stage were independent prognostic factors for the overall survival (OS) of patients with serous EOC. Kaplan–Meier curves revealed a significant association of the increased expression level of lnc-SNHG1 with shorter OS and disease-free survival (DFS). Patients with a low expression level of miR-216b-5p also had shorter OS and DFS. The biological functions were tested using CCK-8 assay, colony formation assay, wound healing assay, and cell apoptosis. The knockdown of SNHG1 and the overexpression of miR-216b-5p stimulated paclitaxel sensitivity in A2780/Taxol cells through inhibiting cell growth and migration and promoting apoptosis. The inhibition of miR-216b-5p could rescue the effect of lnc-SNHG1 inhibition on the sensitivity of A2780/Taxol cells to paclitaxel. Luciferase reporter assay, RNA Binding Protein Immunoprecipitation Assay (RIP), and quantitative reverse transcription–polymerase chain reaction (qRT-PCR) indicated that lnc-SNHG1 acted as a sponge of miR-216b-5p in A2780/Taxol cells.

Conclusions

This study showed that the overexpression of lnc-SNHG1 and decreased expression level of miR-216b-5p correlated with the chemoresistance of patients with serous EOC and indicated shorter OS and DFS. Lnc-SNHG1 functioned as a ceRNA with miR-216b-5p, which was critical in modulating the paclitaxel sensitivity of ovarian cancer cells.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-020-00750-4.

Downregulation of the long noncoding RNA SNHG1 inhibits tumor cell migration and invasion by sponging miR-195 through targeting Cdc42 in oesophageal cancer

Despite the poor prognosis of oesophageal cancer (EC), the molecular mechanisms of EC are still unclear. In recent years, role of lncRNA in cancer development attracted much attention. The present study aimed to investigate the effects of the long noncoding RNA SNHG1 on the migration and invasion of EC cells and the possible mechanisms involved. The effects of SNHG1 on cell proliferation, migration, and invasion were determined and its relationship with miR-195/Cdc42 axis was investigated. It was found SNHG1 and Cdc42 were significantly upregulated, and miR-195 was significantly downregulated in both EC tissues and cell lines. In addition, the inhibition of either SNHG1 or Cdc42 resulted in suppression of cell proliferation, migration, and invasion, while inhibition of miR-195 led to opposite results and reversed the effects of si-SNHG1. We also observed that higher SNHG1 predicted poorer prognosis of EC patients. In summary, inhibition of SNHG1 can suppress the cell migration and invasion of EC cells by sponging miR-195 through targeting Cdc42. This study might provide deeper insights into the SNHG1/miR-195/Cdc42 axis in EC.

Long Non-Coding RNA SNHG1 Regulates the Wnt/β-Catenin and PI3K/AKT/mTOR Signaling Pathways via EZH2 to Affect the Proliferation, Apoptosis, and Autophagy of Prostate Cancer Cell

Background

Prostate cancer (PCa) is the most common malignant cancer in western developed countries, which has seriously threatened the life style and life quality of men. Its pathogenesis and causes remain indistinct. Currently, it is found that lncRNA-SNHG1 (SNHG1) is highly expressed in multiple tumors with proto-oncogene effect, but its function and mechanism in PCa need to be further studied.

Methods

The expression of SNHG1 and EZH2 was detected by RT-qPCR in the 20 pairs of PCa tissue, adjacent tissue and PCa cell lines. They were transfected with siRNA NC, SNHG1 siRNA, EZH2 siRNA, SNHG1 siRNA+empty, and SNHG1 siRNA+EZH2 overexpression. Then, MTT and colony formation assay were used to detect the proliferation and cloning ability of PCa cells LNCaP and PC3. Transwell and flow cytometry were used to measure cell migration and invasion ability and apoptosis level respectively. Immunofluorescence was used to detect the LC3 spot formation. Western blot was used to detect the expression of the autophagy-related proteins, and PI3K/AKT/mTOR and Wnt/β-catenin signaling pathway related proteins. Finally, in vivo nude mice tumorigenesis experiment to explore the effect of SNHG1 expression on PCa.

Results

We found that SNHG1 and EZH2 were up-regulated in PCa tissue and cells. The expression of SNHG1 and EZH2 was positively correlated. RNA pull down and RNA IP assay further confirmed that SNHG1 bound to EZH2. The proliferation, colony formation, migration and invasion of LNCaP and PC3 cells were significantly reduced with the interference with SNHG1or EZH2 compared with the control group. The related proteins of Wnt/β-catenin and PI3K/AKT/mTOR signaling pathway were significantly reduced after the interference with SNHG1 or EZH2; after simultaneous interference with SNHG1 and overexpression of EZH2, the functional effects on LNCaP and PC3 cells interfered with SNHG1 were reversed. These results were also confirmed in vivo nude mice tumor formation experiments.

Conclusions

This study reveals that lncRNA-SNHG1 regulates Wnt/β-catenin and PI3K/AKT/mTOR signaling pathways via EZH2 gene to affect proliferation, apoptosis and autophagy of PCa cells. This experiment provides ideas and experimental basis for the improvement and treatment of PCa.

Epigenetic silencing of CDKN1A and CDKN2B by SNHG1 promotes the cell cycle, migration and epithelial-mesenchymal transition progression of hepatocellular carcinoma

Enhanced SNHG1 (small nucleolar RNA host gene 1) expression has been found to play a critical role in the initiation and progression of hepatocellular carcinoma (HCC) with its detailed mechanism largely unknown. In this study, we show that SNHG1 promotes the HCC progression through epigenetically silencing CDKN1A and CDKN2B in the nucleus, and competing with CDK4 mRNA for binding miR-140-5p in the cytoplasm. Using bioinformatics analyses, we found hepatocarcinogenesis is particularly associated with dysregulated expression of SNHG1 and activation of the cell cycle pathway. SNHG1 was upregulated in HCC tissues and cells, and its knockdown significantly inhibited HCC cell cycle, growth, metastasis, and epithelial–mesenchymal transition (EMT) both in vitro and in vivo. Chromatin immunoprecipitation and RNA immunoprecipitation assays demonstrate that SNHG1 inhibit the transcription of CDKN1A and CDKN2B through enhancing EZH2 mediated-H3K27me3 in the promoter of CDKN1A and CDKN2B, thus resulting in the de-repression of the cell cycle. Dual-luciferase assay and RNA pulldown revealed that SNHG1 promotes the expression of CDK4 by competitively binding to miR-140-5p. In conclusion, we propose that SNHG1 formed a regulatory network to confer an oncogenic function in HCC and SNHG1 may serve as a potential target for HCC diagnosis and treatment.

lncRNA SNHG1 Promotes Basal Bladder Cancer Invasion via Interaction with PP2A Catalytic Subunit and Induction of Autophagy

Although basal muscle-invasive bladder cancers (MIBCs) are predominant, are more aggressive, and have bad prognoses, molecular mechanisms underlying how basal MIBC formation/progression have been barely explored. In the present study, SNHG1, a long non-coding RNA, was shown to be expressed at higher levels in basal MIBC cells than in other types of bladder BC cells, and its presence could promote basal MIBC cell invasion. The results revealed that SNHG1 specifically induced MMP2 expression via increasing its transcription and mRNA stability. In one mechanism, SNHG1 directly bound with PP2A catalytic subunit (PP2A-c) to inhibit interactions of PP2A-c with c-Jun and then promoted c-Jun phosphorylation that, in turn, mediated MMP2 transcription. In another mechanism, SNHG1 markedly induced autophagy in the cells via induction of increases in the abundance of autophagy-related proteins. The latter initiated autophagy and further abolished miR-34a stability, which reduced overall miR-34a binding directly to the 3' UTR of MMP2 mRNA, thereby promoting MMP2 mRNA stabilization. These results provided novel insight into understanding the specific functions of SNHG1 in basal MIBC. Such findings may ultimately prove highly significant for the design/synthesis of new SNHG1-based compounds for the treatment of basal MIBC patients.

Integrative Analysis of Three Novel Competing Endogenous RNA Biomarkers with a Prognostic Value in Lung Adenocarcinoma

Increasing evidence has shown competitive endogenous RNAs (ceRNAs) play key roles in numerous cancers. Nevertheless, the ceRNA network that can predict the prognosis of lung adenocarcinoma (LUAD) is still lacking. The aim of the present study was to identify the prognostic value of key ceRNAs in lung tumorigenesis. Differentially expressed (DE) RNAs were identified between LUAD and adjacent normal samples by limma package in R using The Cancer Genome Atlas database (TCGA). Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway function enrichment analysis was performed using the clusterProfiler package in R. Subsequently, the LUAD ceRNA network was established in three steps based on ceRNA hypothesis. Hub RNAs were identified using degree analysis methods based on Cytoscape plugin cytoHubba. Multivariate Cox regression analysis was implemented to calculate the risk score using the candidate ceRNAs and overall survival information. The survival differences between the high-risk and low-risk ceRNA groups were determined by the Kaplan-Meier and log-rank test using survival and survminer package in R. A total of 2,989 mRNAs, 185 lncRNAs, and 153 miRNAs were identified. GO and KEGG pathway function enrichment analysis showed that DE mRNAs were mainly associated with “sister chromatid segregation,” “regulation of angiogenesis,” “cell adhesion molecules (CAMs),” “cell cycle,” and “ECM-receptor interaction.” LUAD-related ceRNA network was constructed, which comprised of 54 nodes and 78 edges. Top ten hub RNAs (hsa-miR-374a-5p, hsa-miR-374b-5p, hsa-miR-340-5p, hsa-miR-377-3p, hsa-miR-21-5p, hsa-miR-326, SNHG1, RALGPS2, and PITX2) were identified according to their degree. Kaplan-Meier survival analyses demonstrated that hsa-miR-21-5p and RALGPS2 had a significant prognostic value. Finally, we found that a high risk of three novel ceRNA interactions (SNHG1-hsa-miR-21-5p-RALGPS2, SNHG1-hsa-miR-326-RALGPS2, and SNHG1-hsa-miR-377-3p-RALGPS2) was positively associated with worse prognosis. Three novel ceRNAs (SNHG1-hsa-miR-21-5p-RALGPS2, SNHG1-hsa-miR-326-RALGPS2, and SNHG1-hsa-miR-377-3p-RALGPS2) might be potential biomarkers for the prognosis and treatment of LUAD.

A prognostic model composed of four long noncoding RNAs predicts the overall survival of Asian patients with hepatocellular carcinoma

Based on accumulating evidence, long noncoding RNAs (lncRNAs) are potential biomarkers and therapeutic targets for many diseases, including tumors. In this study, we consulted The Cancer Genome Atlas (TCGA) database to explore the functions and modulatory mechanisms of lncRNAs as competing endogenous RNAs (ceRNAs) in hepatocellular carcinoma (HCC) in Asian patients and constructed a risk scoring system composed of four lncRNAs (SNHG1, STEAP3-AS1, RUSC1-AS1, and SNHG3) to predict the outcomes of Asian patients with HCC. The prognostic value of this risk model was validated in the internal validation cohort (n = 157). The stratified survival analysis revealed good performance for the risk model in stratifying clinical features. According to the Cox proportional hazard regression analysis, the four-lncRNA risk model is an independent prognostic model for Asian patients with HCC. Finally, we developed a nomogram that integrates prognostic signals and other clinical information to predict 1-, 3-, and 5-year overall survival rates. In conclusion, the prognostic lncRNAs identified in our study exerted potential biological effects on the development of HCC. The risk scoring model based on four lncRNAs may be an effective classification tool for assessing the prognosis of Asian patients with HCC.

Long Non-Coding RNAs in Biliary Tract Cancer-An Up-to-Date Review

The term long non-coding RNA (lncRNA) describes non protein-coding transcripts with a length greater than 200 base pairs. The ongoing discovery, characterization and functional categorization of lncRNAs has led to a better understanding of the involvement of lncRNAs in diverse biological and pathological processes including cancer. Aberrant expression of specific lncRNA species was demonstrated in various cancer types and associated with unfavorable clinical characteristics. Recent studies suggest that lncRNAs are also involved in the development and progression of biliary tract cancer, a rare disease with high mortality and limited therapeutic options. In this review, we summarize current findings regarding the manifold roles of lncRNAs in biliary tract cancer and give an overview of the clinical and molecular consequences of aberrant lncRNA expression as well as of underlying regulatory functions of selected lncRNA species in the context of biliary tract cancer.

An Emerging Class of Long Non-coding RNA With Oncogenic Role Arises From the snoRNA Host Genes

The small nucleolar RNA host genes (SNHGs) are a group of long non-coding RNAs, which are reported in many studies as being overexpressed in various cancers. With very few exceptions, the SNHGs (SNHG1, SNHG3, SNHG5, SNHG6, SNHG7, SNHG12, SNHG15, SNHG16, SNHG20) are recognized as inducing increased proliferation, cell cycle progression, invasion, and metastasis of cancer cells, which makes this class of transcripts a viable biomarker for cancer development and aggressiveness. Through our literature research, we also found that silencing of SNHGs through small interfering RNAs or short hairpin RNAs is very effective in both in vitro and in vivo experiments by lowering the aggressiveness of solid cancers. The knockdown of SNHG as a new cancer therapeutic option should be investigated more in the future.

Long non-coding RNAs: How to regulate the metastasis of non-small-cell lung cancer

Non–small‐cell lung cancer (NSCLC) has become the most lethal human cancer because of the high rate of metastasis. Hence, clarifying the molecular mechanism underlying NSCLC metastasis is very important to improve the prognosis of patients with NSCLC. Long non‐coding RNAs (LncRNAs) are a class of RNA molecules longer than 200 nucleotides, which can participate in diverse biological processes. About 18% of human LncRNAs were recently found to be associated with tumours. Many studies indicated that aberrant expression of LncRNAs played key roles in the progression and metastasis of NSCLC. According to the function in tumours, LncRNAs can be divided into two classes: oncogenic LncRNAs and tumour‐suppressor LncRNAs. In this review, we summarized the main molecular mechanism of LncRNAs regulating NSCLC metastasis, including three aspects: (a) LncRNAs interact with miRNAs as ceRNAs; (b) LncRNAs bind with target proteins; and (c) LncRNAs participate in the transduction of different signal pathways. Then, LncRNAs can exert their function to regulate the metastasis of NSCLC through influencing the progression of epithelial‐mesenchymal transition (EMT) and the properties of cancer stem cell (CSC). But, it is necessary to do some further research to demonstrate the LncRNAs particular regulatory mechanism of inhibiting the metastasis of NSCLC and explore new drugs targeting LncRNAs.

Small Nucleolar RNA Host Gene 1 (SNHG1) and Chromosome 2 Open Reading Frame 48 (C2orf48) as Potential Prognostic Signatures for Liver Cancer by Constructing Regulatory Networks

Background

Liver cancer is a common malignant tumor with poor prognosis. The present study sought to identify potential signatures that can predict the prognosis of patients with liver cancer.

Material/Methods

The RNA sequencing (RNA-seq) and clinical information of liver cancer patients were obtained from the Cancer Genome Atlas (TCGA) database. Differentially expressed long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and messenger RNAs (mRNAs) were identified between liver cancer and adjacent normal tissues. After predicting lncRNA–miRNA and miRNA–mRNA pairs using online databases, the competing endogenous RNA (ceRNA) networks were constructed. Furthermore, the prognostic value of these differentially expressed genes was evaluated using univariate and multivariate Cox regression analyses.

Results

After constructing the ceRNA network, 2 lncRNAs small nucleolar RNA host gene 1 (SNHG1) and chromosome 2 open reading frame 48 (C2orf48) with the most nodes were identified. Correlation analysis revealed that SNHG1 was correlated with miR-195 and C2orf48 was correlated with miR-195 and miR-93. High expression of SNHG1, C2orf48, and miR-93 can contribute to poorer clinical outcomes compared to low expression. Furthermore, low miR-195 expression was correlated with shorter survival time than was high expression. SNHG1 and C2orf48 were closely associated with histology grade. Univariate and multivariate Cox regression analyses confirmed that SNHG1 and C2orf48 are risk factors for liver cancer.

Conclusions

Our findings revealed that SNHG1 and C2orf48 possess potential prognostic value and should be considered as possible biomarkers for predicting clinical outcomes for patients with liver cancer.

Can small nucleolar RNA be a novel molecular target for hepatocellular carcinoma?

BACKGROUND

Globally, hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death. Recently, many studies have demonstrated that small nucleolar RNA (snoRNA) was closely related to HCC.

OBJECTIVE

To explore whether snoRNA can be used as a molecular target for HCC.

METHODS

The PubMed, Embase, and Cochrane databases were searched for the published literatures related to snoRNA and HCC until August 12, 2019. After identification, screening, and verification, this study finally included 26 studies correlating small nucleolar RNA host gene (SNHG) and HCC, and 8 studies correlating snoRNA and HCC. Based on the collation of the relevant literature, the correlation network diagram between snoRNAs and HCC was constructed.

RESULTS

The SNHGs, such as SNHG1, SNHG6, SNHG16, and SNHG20 can play varied roles in HCC through different regulatory mechanisms. These SNHGs can promote and inhibit tumorigenesis. SNORD76 can promote the proliferation of tumor tissues and cells in vitro through different pathways. SnoU2_19 and SNORD76 can function through the same pathway. SNHG3, SNHG20, SNHG6, SNORD76, and snoRA47 can modulate epithelial-mesenchymal transition (EMT) to regulate the development of HCC cell or tissue. SNHG16, SNORD76, and SnoU2_19 can regulate the development of HCC through Wnt/β-catenin signaling pathway.

CONCLUSION

snoRNA can regulate the occurrence of HCC by modulating multiple molecular signaling pathways. Hence, snoRNA can be a potential molecular target for HCC.

SEMA3F Promotes Liver Hepatocellular Carcinoma Metastasis by Activating Focal Adhesion Pathway

Previous studies have shown that semaphorin-3F (SEMA3F) functions as a tumor suppressor in several tumor types. However, the role of SEMA3F in the metastasis and prognosis of liver hepatocellular carcinoma (LIHC) remains unknown. In this study, by performing bioinformatics analysis on the transcriptome profiles from The Cancer Genome Atlas (TCGA), we demonstrated that SEMA3F was significantly upregulated in LIHC tissues, compared with normal controls. Moreover, the expression value of SEMA3F was positively correlated with patients' pathological stages and tumor metastasis, predicting a poor overall survival. Besides, SEMA3F expression level was negatively correlated with its methylation level, but positively correlated with its gene copy number. Differential expression analysis of LIHC samples with high or low SEMA3F expression values suggested that 983 genes were differentially expressed, among which 723 genes were upregulated and 260 genes were downregulated. Furthermore, enrichment analysis of differentially expressed genes revealed that SEMA3F was involved in the activation of focal adhesion pathway, which induced tumor metastasis. Taken together, our results suggested that the oncogenic function of SEMA3F promoted hepatocellular carcinoma metastasis by activating focal adhesion pathway.

Up-Regulation of MicroRNA-21 Indicates Poor Prognosis and Promotes Cell Proliferation in Esophageal Squamous Cell Carcinoma via Upregulation of lncRNA SNHG1

Introduction

MicroRNA-21 (miRNA-21) and lncRNA SNHG1 (small nucleolar RNA host gene 1) are known to be aberrantly upregulated and promote tumor progression in various cancers. Nevertheless, very few studies have determined the roles of tissue and circulating miRNA-21 and SNHG1 in ESCC patients. Particularly, knowledge about the characteristics of miRNA-21 and SNHG1 expression and their correlations with survival rates, as well as their interaction with each other remains inadequate in ESCC.

Methods

Thse expression level of miRNA-21 and SNHG1 of tissues, serum and cell lines were detected by qRT-PCR, and the characteristics of their expression and clinicopathology were analyzed. Then, the diagnostic and prognosis value of serum and tissue miRNA-21 and SNHG1 were evaluated, respectively. In addition, the interaction with each other between miRNA-21 and SNHG1, as well as the effect on ESCC cell proliferation were further clarified.

Results

The expression level of miRNA-21 and SNHG1 are significantly upregulated in tissues, serum and cell lines of ESCC, and tissue miRNA-21 and SNHG1 significantly correlates with lymph node metastasis, TNM stage, tumor size, and poor overall survival in ESCC patients. The receiver operating characteristic (ROC) curves show that areas under the ROC curve (AUC) for serum miRNA-21 and SNHG1 are 0.928 and 0.850, respectively. Pearson correlation coefficient indicated that the expression levels of miRNA-21 and SNHG1 in frozen cancerous tissues are significantly associated with their respective serum levels. Further, Cox univariate and multivariate analyses reveal that miRNA-21 and SNHG1 are independent prognostic factors for overall survival (OS) and disease-free survival (DFS) in ESCC patients. In addition, our in vitro data revealed a novel regulatory pathway, in which miRNA-21 is probably a unidirectional upstream positive regulator of SNHG1 in ESCC cells, and the interaction between miRNA-21 and SNHG1 plays an important role in the proliferation of ESCC cells.

Discussion

In summary, our data show that SNHG1 may be a novel downstream target of miRNA-21 and not vice versa in ESCC cells and contributes significantly toward the proliferation of ESCC cells. These findings suggest that miRNA-21 and SNHG1 may serve as potential diagnostic, prognostic biomarkers and therapeutic targets for ESCC patients.

Transcriptome alteration spectrum in rat lung induced by radiotherapy

Radiation therapy is crucial for curative treatment of lung cancer, which frequently leads to lung injury. Long non-coding RNAs (lncRNAs) are a group of RNAs longer than 200 nucleotides and lack protein-coding capacity. Increasing evidences demonstrate the important roles of lncRNAs in biological processes. However, the mechanism underlying the association of ionizing radiation with alterations in mRNA and lncRNA expression and lung injury remains unclear. In our study, the male Sprague-Dawley (SD) rats were exposed to a dose of 18 Gy of 6 MV X-ray and the transcriptome spectrum was studied. To identify the differentially expressed mRNAs and lncRNAs induced by X-ray, the RNA sequencing data of lung tissues from irradiated and normal rats for 4, 8, and 16 weeks were analyzed, using |log2_ratio| ≥ 1 and q ≤ 0.05 as thresholds for significantly differential expression. The number of differentially expressed mRNAs was 1097 (686 up- and 411 down-) for 4-week radiotherapy group, 3006 (1935 up- and 1071 down-) for 8-week group and 1838 (1178 up- and 660 down-) for 16-week group. There were 606 (279 up- and 327 down-) differentially expressed lncRNAs in 4-week group, 1715 (831 up- and 884 down-) in 8-week group and 1043 (656 up- and 387 down-) in 16-week group. The differentially expressed mRNAs were mainly involved in cell cycle regulation and Fc receptor pathway, while the lncRNA target genes were significantly enriched in cellular stress response and regulation of cell migration. Moreover, compared with the control group, the irradiated group presented higher tissue specificity of lncRNAs. Radiation-induced lung injury, especially the dynamic network of lncRNAs and mRNAs, is worthy of study. Investigation on the regulatory details of related pathways is significant for the prevention of radiation-related lung injury, as well as the improvement of radiation therapy.

Comprehensive analysis of differentially expressed lncRNAs as diagnostic and prognostic markers for colorectal cancer

Colorectal cancer (CRC) is the third most common type of cancer worldwide. Recent studies had revealed the important roles of long non-coding RNAs (lncRNAs) in a variety of human cancers, including CRC. However, the molecular mechanisms associated with CRC remain largely undetermined. In the current study, the GSE21510 dataset was analyzed to identify differentially expressed mRNAs and lncRNAs in CRC samples. The Database for Annotation, Visualization and Integrated Discovery was used to perform Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway bioinformatics analysis. Furthermore, protein-protein interaction networks were constructed to reveal interactions among differentially expressed proteins. Kaplan-Meier analysis was subsequently performed to determine the association between key lncRNA expression and the overall survival of patients with CRC. A total of 107 upregulated lncRNAs and 43 downregulated lncRNAs were identified in CRC. A lncRNA mediated co-expression network was also constructed in CRC. Bioinformatics analysis indicated that lncRNAs were associated with a series of biological processes, including 'xenobiotic glucuronidation', 'rRNA processing', 'sister chromatid cohesion', 'cell proliferation', 'mitotic nuclear division' and 'cell cycle regulation'. Furthermore, a higher expression of small nucleolar RNA host gene 17, tetratricopeptide repeat domain 2B-antisense RNA (AS) 1, erythrocyte membrane protein band 4.1 like 4A-AS2, deleted in lymphocytic leukemia 2, and a lower expression of muscle blind like splicing regulator 1-AS1 and LOC389332 were associated with shorter overall survival time in CRC samples. The present study provides useful information that can be used in the identification of novel biomarkers for CRC.

LINC00511 as a ceRNA promotes cell malignant behaviors and correlates with prognosis of hepatocellular carcinoma patients by modulating miR-195/EYA1 axis

BACKGROUND

Recently, a growing number of reports indicated that long non-coding RNAs (lncRNAs) were involved in the development of various cancers. However, the performance of LINC00511 is still limited in hepatocellular carcinoma (HCC). Thus, we attempted to assess the effect of LINC00511 and underlying mechanism in HCC progression.

METHODS

TCGA and GEO database acted as supporters to provide us clinical samples data. Overall survival (OS) analyses were plotted using Kaplan-Meier method. Five cell lines were utilized to detect LINC00511 expression level and Cell Counting Kit-8 (CCK-8), colony formation and transwell assays were conducted to examine the effects on cell behaviors. The correlations between LINC00511 and miR-195 or eyes absent homolog 1 (EYA1) were confirmed by luciferase reporter assay. Quantitative real-time PCR and western blotting were fulfilled to ascertain the mRNA and protein expression levels.

RESULTS

In this study, we found that LINC00511 was high-regulated in HCC tissue samples and cell lines, which might be linked with unfavorable prognosis of HCC patients and clinical parameters. Loss-of-function experiments determined that LINC00511 deficiency inhibited cell proliferation, colony formation and invasive activity in HepG2 cells, while gain-of-function experiments showed the counter impacts in Huh7 cells. Bioinformatics tools and luciferase reporter assays revealed that LINC00511 may act as a competing endogenous RNA (ceRNA) for miR-195 and positively correlate with EYA1, which was reinforced by rescue experiments.

CONCLUSION

Taken together, these findings indicated that LINC00511 interacted with EYA1 promoted HCC development via mediating miR-195, proposing a promising therapeutic biomarker for HCC diagnosis and prognosis.

Long non-coding small nucleolar RNA host genes in digestive cancers

Although long noncoding RNAs (lncRNAs) do not have protein coding capacities, they are involved in the pathogenesis of many types of cancers, including hepatocellular carcinoma, cervical cancer, and gastric cancer. Notably, the roles of lncRNAs are vital in nearly every aspect of tumor biology. Long non‐coding small nucleolar RNA host genes (lnc‐SNHGs) are abnormally expressed in multiple cancers, including urologic neoplasms, respiratory tumors, and digestive cancers, and play vital roles in these cancers. These host genes could participate in tumorigenesis by regulating proliferation, migration, invasion and apoptosis of tumor cells. This review focuses on the overview of the roles that lnc‐SNHGs play in the formation and progression of digestive cancers.

lncRNA GAS5-promoted apoptosis in triple-negative breast cancer by targeting miR-378a-5p/SUFU signaling

PURPOSE

Long-chain noncoding RNAs (lncRNAs) are involved in regulating the sensitivity of cancer cells to chemotherapeutic drugs, but the specific mechanism of action is not well understood. The aim of this study was to investigate the effect of lncRNA growth-stasis specific transcript 5 (GAS5) on triple-negative breast cancer (TNBC).

METHODS

Quantitative real-time polymerase chain reaction and flow cytometry were used to screen lncRNA associated with tumor resistance. Double luciferase reporter gene assay, flow cytometry, and Western blot assay were used to determine whether miRNA 378a-5p and SUFU were involved in tumor cell apoptosis induced by lncRNA GAS5. A mouse model of subcutaneous xenografts was established to investigate the relationship between lncRNA GAS5 and tumor resistance in vivo.

RESULTS

In this study, the expression of lncRNA GAS5 was significantly downregulated in cells treated with paclitaxel (PTX) or cisplatin (CIS). Furthermore, TNBC cells with low expression of lncRNA GAS5 had a lower percentage of apoptosis under stress conditions, especially in serum-free medium. More interestingly, the expression level of lncRNA GAS5 in TNBC patients was associated with tumor resistance to PTX and CIS. In addition, RNA immunoprecipitation experiments confirmed that lncRNA GAS5 and miR-378 could directly bind to each other. Moreover, the miR-378a-5p target of SUFU could promote lncRNA GAS5-induced apoptosis of TNBC cells. Finally, lncRNA GAS5 overexpressed MDA-231R could enhance the sensitivity of TNBC to PTX.

CONCLUSION

The above results confirmed that lncRNA GAS5 could induce apoptosis in TNBC cells by targeting miR-378a-5p/SUFU signaling.

A novel long non-coding RNA LINC00355 promotes proliferation of lung adenocarcinoma cells by down-regulating miR-195 and up-regulating the expression of CCNE1

Lung adenocarcinoma is the most common subtype of non-small-cell lung cancer affecting people all over the globe. Recent studies have indicated that long non-coding RNAs (lncRNAs) possess the ability to regulate gene expression. Initially, we uncovered increased LINC00355 expressions in lung adenocarcinoma tissues and cells. Functionally, our findings demonstrated that LINC00355 silencing suppressed the proliferation in vitro and in vivo. In addition, we found that LINC00355 negatively regulated miR-195 in lung adenocarcinoma cells. Simultaneously, silencing LINC00355 by shRNA resulted in suppressed proliferation, colony formation and promoted cell cycle arrest and apoptosis via miR-195. Moreover, silencing LINC00355 by shRNA inhibited the cyclin E1 (CCNE1) gene expression via miR-195 in lung adenocarcinoma cells. Collectively, this study demonstrates the novel lncRNA LINC00355 in regulatory network of CCNE1 via miR-195 in lung adenocarcinoma, highlighting LINC00355 as a new target for the treatment of lung adenocarcinoma.

Identification of key genes and long non-coding RNA associated ceRNA networks in hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. Although multiple efforts have been made to understand the development of HCC, morbidity, and mortality rates remain high. In this study, we aimed to discover the mRNAs and long non-coding RNAs (lncRNAs) that contribute to the progression of HCC. We constructed a lncRNA-related competitive endogenous RNA (ceRNA) network to elucidate the molecular regulatory mechanism underlying HCC.

Methods

A microarray dataset (GSE54238) containing information about both mRNAs and lncRNAs was downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) and lncRNAs (DElncRNAs) in tumor tissues and non-cancerous tissues were identified using the limma package of the R software. The miRNAs that are targeted by DElncRNAs were predicted using miRcode, while the target mRNAs of miRNAs were retrieved from miRDB, miRTarBas, and TargetScan. Functional annotation and pathway enrichment of DEGs were performed using the EnrichNet website. We constructed a protein–protein interaction (PPI) network of DEGs using STRING, and identified the hub genes using Cytoscape. Survival analysis of the hub genes and DElncRNAs was performed using the gene expression profiling interactive analysis database. The expression of molecules with prognostic values was validated on the UALCAN database. The hepatic expression of hub genes was examined using the Human Protein Atlas. The hub genes and DElncRNAs with prognostic values as well as the predictive miRNAs were selected to construct the ceRNA networks.

Results

We found that 10 hub genes (KPNA2, MCM7, CKS2, KIF23, HMGB2, ZWINT, E2F1, MCM4, H2AFX, and EZH2) and four lncRNAs (FAM182B, SNHG6, SNHG1, and SNHG3) with prognostic values were overexpressed in the hepatic tumor samples. We also constructed a network containing 10 lncRNA–miRNA–mRNA pathways, which might be responsible for regulating the biological mechanisms underlying HCC.

Conclusion

We found that the 10 significantly overexpressed hub genes and four lncRNAs were negatively correlated with the prognosis of HCC. Further, we suggest that lncRNA SNHG1 and the SNHG3-related ceRNAs can be potential research targets for exploring the molecular mechanisms of HCC.

MicroRNA and mRNA Interaction Network Regulates the Malignant Transformation of Human Bronchial Epithelial Cells Induced by Cigarette Smoke

This study analyzes the correlation and interaction of miRNAs and mRNAs and their biological function in the malignant transformation of BEAS-2B cells induced by cigarette smoke (CS). Normal human bronchial epithelial cells (BEAS-2B) were continuously exposed to CS for 30 passages (S30) to establish an in vitro cell model of malignant transformation. The transformed cells were validated by scratch wound healing assay, transwell migration assay, colony formation and tumorigenicity assay. The miRNA and mRNA sequencing analysis were performed to identify differentially expressed miRNAs (DEMs) and differentially expressed genes (DEGs) between normal BEAS-2B and S30 cells. The miRNA-seq data of lung cancer with corresponding clinical data obtained from TCGA was used to further identify lung cancer-related DEMs and their correlations with smoking history. The target genes of these DEMs were predicted using the miRDB database, and their functions were analyzed using the online tool “Metascape.” It was found that the migration ability, colony formation rate and tumorigenicity of S30 cells enhanced. A total of 42 miRNAs and 753 mRNAs were dysregulated in S30 cells. The change of expression of top five DEGs and DEMs were consistent with our sequencing results. Among these DEMs, eight miRNAs were found dysregulated in lung cancer tissues based on TCGA data. In these eight miRNAs, six of them including miR-96-5p, miR-93-5p, miR-106-5p, miR-190a-5p, miR-195-5p, and miR-1-3p, were found to be associated with smoking history. Several DEGs, including THBS1, FN1, PIK3R1, CSF1, CORO2B, and PREX1, were involved in many biological processes by enrichment analysis of miRNA and mRNA interaction. We identified the negatively regulated miRNA-mRNA pairs in the CS-induced lung cancer, which were implicated in several cancer-related (especially EMT-related) biological process and KEGG pathways in the malignant transformation progress of lung cells induced by CS. Our result demonstrated the dysregulation of miRNA-mRNA profiles in cigarette smoke-induced malignant transformed cells, suggesting that these miRNAs might contribute to cigarette smoke-induced lung cancer. These genes may serve as biomarkers for predicting lung cancer pathogenesis and progression. They can also be targets of novel anticancer drug development.

LINC00473 promotes hepatocellular carcinoma progression via acting as a ceRNA for microRNA-195 and increasing HMGA2 expression

Hepatocellular carcinoma (HCC) is a most aggressive malignant tumor. Nevertheless, the molecular mechanisms underlying HCC are still completely unclear. LINC00473 is identified as a tumor promoter in many cancers. In this investigation, the function of LINC00473 was specifically focused on. We exhibited that LINC00473 was obviously elevated in HCC cells compared to QSG-7701 cells. Functionally, down-regulation of LINC00473 could prevent HCC cell viability and cell proliferation. For another, HCC cell colony formation capacity was greatly restrained while cell apoptosis was triggered by loss of LINC00473. Meanwhile, would-healing assay and transwell invasion experiments were employed in our present study. As demonstrated, we observed that HCC cell migratory and invasive ability were obviously suppressed by the silence of LINC00473. Apart from these, mechanistic investigations implied miR-195 was a sponge target of LINC00473. It is widely established miR-195 is a famous tumor inhibitory gene regulator in various cancers. Here, we confirmed the binding correlation between LINC00473 and miR-195 using RIP assay. Subsequently, in vivo experiments were employed and it was manifested that LINC00473 was able to promote HCC tumor growth via acting as a ceRNA to inhibit miR-195. HMGA2 is a kind of nuclear-binding protein and it is involved in various cancers. We predicted it as a target of miR-195 and we confirmed their correlation. In addition, HMGA2 was repressed by loss of LINC00473, which was rescued by miR-195 inhibitors. Then, we found that angiogenic fator vascular endothelial growth factor (VEGF) was inhibited by loss of LINC00473 whereas anti-angiogenic factor EPN2 was induced in vivo. Taken all these together, our study revealed the significance of LINC00473/miR-195/HMGA2 signaling axis for the first time in HCC progression. It was suggested the potential possibility of LINC00473 as an indicator for HCC.

Long non-coding RNA NEAT1/miR-193a-3p regulates LPS-induced apoptosis and inflammatory injury in WI-38 cells through TLR4/NF-κB signaling

Pneumonia is a primary pulmonary infection disease with a high morbidity and mortality worldwide. Identification of key long non-coding RNAs (lncRNAs) facilitates to the development of effective therapeutic targets for pneumonia. LncRNA NEAT1 was vital and functional in inflammatory diseases but has not been studied in pneumonia. The aim of this study was to investigate the role of NEAT1 in pneumonia and explore its potential mechanism. Lipopolysaccharide (LPS) was applied into WI-38 cells to establish cell model of pneumonia. Cells were transfected with shRNA-NEAT1, miR-193a-3p or negative control. Real time quantitative PCR and western blot were performed to detect mRNA level and protein expression, respectively. Cell counting kit-8 (CCK-8) assay was performed to detect cell viability. Flow cytometry analysis was performed to determine cell apoptosis. Cell viability was significantly declined and cell apoptosis was increased in LPS-treated WI-38 cells. NEAT1 was upregulated under LPS treatment and NEAT1 inhibition significantly improved cell viability, decreased cell apoptosis and the production of inflammatory cytokines. The expression level of miR-193a-3p was regulated by NEAT1, and NEAT1 reversed miR-193a-3p overexpression-alleviated inflammatory injury that include inflammation and apoptosis induced by LPS. Further, NEAT1 and miR-193a-3p regulated the activity of Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) signaling. Therefore, NEAT1 may function as a ceRNA by sponging miR-193a-3p to regulate the activation of TLR4/NF-κB signaling to alleviate inflammation and apoptosis of WI-38 cells induced by LPS, thus influencing the development of pneumonia. Our findings implied that NEAT1 might serve as a neoteric therapy target for pneumonia.

LncRNA SNHG1 alleviates IL-1β-induced osteoarthritis by inhibiting miR-16-5p-mediated p38 MAPK and NF-κB signaling pathways

Long non-coding RNA (LncRNA) small nucleolar RNA host gene 1 (SNHG1) has been reported in the occurrence and development of several diseases, but its biological role and mechanism in osteoarthritis (OA) remain to be illuminated. In the present research, we aimed to investigate the effect of SNHG1 on IL-1β-induced OA and its molecular mechanism. Results revealed that SNHG1 decreased the expression of MMPs, ADAMTs, collagen, and aggrecan, and ameliorates IL-1β-induced metabolic dysfunction in normal human chondrocytes-keen. In addition, SNHG1 inhibited the expressions of pro-inflammatory cytokines in chondrocytes, including NO, PGE2, IL-6, TNF-α, i-NOS, and COX-2. Furthermore, luciferase reporter assay demonstrated that SNHG1 could directly interact with miR-16-5p and suppressed miR-16-5p expression and activity. What is more, miR-16-5p overexpression reversed SNHG1-inhibited aberrant catabolism and inflammation triggered by IL-1β stimulation. Finally, SNHG1 inhibits the expression of miR-16-5p-mediated factors involved in p38MAPK and NF-κB signaling pathways, including ERK1/2, p-p38 and p-p65. Taken together, the results of our studies illuminate that SNHG1 alleviates the inflammation of IL-1β-induced OA through the activation of miR-16-5p-mediated p38MAPK and NF-κB signaling pathway. It suggested that SNHG1 may serve as a potential target for OA diagnosis and treatment.

Long Non-Coding RNA in the Pathogenesis of Cancers

The incidence and mortality rate of cancer has been quickly increasing in the past decades. At present, cancer has become the leading cause of death worldwide. Most of the cancers cannot be effectively diagnosed at the early stage. Although there are multiple therapeutic treatments, including surgery, radiotherapy, chemotherapy, and targeted drugs, their effectiveness is still limited. The overall survival rate of malignant cancers is still low. It is necessary to further study the mechanisms for malignant cancers, and explore new biomarkers and targets that are more sensitive and effective for early diagnosis, treatment, and prognosis of cancers than traditional biomarkers and methods. Long non-coding RNAs (lncRNAs) are a class of RNA transcripts with a length greater than 200 nucleotides. Generally, lncRNAs are not capable of encoding proteins or peptides. LncRNAs exert diverse biological functions by regulating gene expressions and functions at transcriptional, translational, and post-translational levels. In the past decade, it has been demonstrated that the dysregulated lncRNA profile is widely involved in the pathogenesis of many diseases, including cancer, metabolic disorders, and cardiovascular diseases. In particular, lncRNAs have been revealed to play an important role in tumor growth and metastasis. Many lncRNAs have been shown to be potential biomarkers and targets for the diagnosis and treatment of cancers. This review aims to briefly discuss the latest findings regarding the roles and mechanisms of some important lncRNAs in the pathogenesis of certain malignant cancers, including lung, breast, liver, and colorectal cancers, as well as hematological malignancies and neuroblastoma.

Small nucleolar RNA host gene 1 promotes development and progression of colorectal cancer through negative regulation of miR-137

Small nucleolar RNA host gene 1 (SNHG1) is critical in the progression of cancers. However, the mechanism by which SNHG1 regulates the progression of colorectal cancer (CRC) remains unclear. Expressions of SNHG1 and miR‐137 in CRC tissues and cell lines were evaluated by quantitative real‐time polymerase chain reaction. A luciferase reporter gene assay was conducted to investigate miR‐137 target. Additionally, RNA pull‐down assay was performed to explore the physical association between miR‐137, SNHG1, and RNA induced silencing complex (RISC). Cell cycling and invasion were examined by flow cytometry (FCM) and transwell assays. The in vivo carcinogenic activity of SNHG1 was examined using murine xenograft models. Expression of RICTOR, serine/threonine kinase 1 (AKT), serum and glucocorticoid‐inducible kinase 1 (SGK1), p70S6K1, and LC3II/LC3I ratio was examined by Western blot analysis. SNHG1 upregulation was observed in CRC tissues and cell lines, which was associated with the lymph node metastasis, advanced TNM stage and poorer prognosis. SNHG1 increased RICTOR level in CRC via sponging miR‐137. In addition, SNHG1 silencing inhibited CRC cell proliferation and migration in vitro and in vivo. SNHG1 regulated RICTOR expression by sponging miR‐137 and promoted tumorgenesis in CRC.

The prognostic value of lncRNA SNHG1 in cancer patients: a meta-analysis

BACKGROUND

Increasing evidence revealed that high expression level of lncRNA SNHG1 was associated with the unfavorable prognosis of cancer and maybe used as a valuable biomarker for cancer patients. The present meta->analysis is to analyze existing data to reveal potential clinical application of SNHG1 on cancer prognosis and tumor progression. All of the included studies were collected through a variety of retrieval strategies. And the articles were qualified by MOOSE and PRISMA checklists.

METHODS

Up to Mar 20, 2018, literature collection was performed by comprehensive search through electronic databases, including the Cochrane library, PubMed, Embase, Web of science, Springer, Science direct, and three Chinese databases: CNKI, Weipu, and Wanfang. We analyzed 14 studies that met the criteria, and concluded that the increased SHNG1 level was correlated with poor OS and tumor progression.

RESULTS

The combined results indicated that elevated SNHG1 expression level was significantly associated with poor OS (HR = 2.06, 95% CI: 1.69-2.52, P < 0.01) and PFS (HR = 2.78, 95% CI: 1.69-4.55, P < 0.01) in various cancers. Moreover, the promoted SNHG1 expression was also associated with tumor progression ((III/IV vs. I/II: HR = 1.89, 95% CI: 1.53-2.34, P < 0.01). In stratified analyses, a significantly unfavorable association of elevated lncRNA SNHG1 and OS was observed in both digestive system (HR = 2.04, 95% CI: 1.56-2.68, P < 0.01) and non-digestive system (HR = 2.09, 95% CI: 1.55-2.83, P < 0.01) cancer patients.

CONCLUSIONS

The present analysis indicated that the increased SNHG1 is associated with poor OS in patients with general tumors and may be served as a useful prognostic biomarker.

Long intergenic noncoding RNA SNHG16 interacts with miR-195 to promote proliferation, invasion and tumorigenesis in hepatocellular carcinoma

Long non-coding RNAs (lncRNAs) have been confirmed crucial regulators in tumorgenesis. Small nucleolar RNA host gene 16 (SNHG16) has been recently shown to be dysregulated, which uncovered to be a potential oncogene in some cancers. However, the biological function and potential mechanism of SNHG16 in hepatocellular carcinoma (HCC) remain unclear. In our study, our observations showed that the expression level of SNHG16 in HCC tissues and cell lines was upregulated compared with adjacent noncancerous tissues and normal cells. In vitro, loss-of-function experiments revealed that SNHG16 knockdown suppressed the proliferation and weakened invasion of SMMC7721 and HepG2 cells. miR-195 expression was significantly decreased in HCC tissues and negatively correlated with SNHG16 expression. Furthermore, RIP and dual luciferase reporter assays showed that SNHG16 acted as an endogenous sponge by directly binding to miR-195 and downregulated its expression. SNHG16 overexpression inverted the inhibitory effect of miR-195 on proliferation and invasion of SMMC7721 and HepG2 cells. Additionally, SNHG16 depletion resulted in lower tumor growth and weight loss, in vivo. In conclusion, our findings reported that the oncogenic role of SNHG16 in HCC tumorigenesis through a novel SNHG16-miR-195 axis, which provided a novel insight for HCC and helped to probe a potential therapeutic target for the deadly disease.