LncRNA SNHG3 is activated by E2F1 and promotes proliferation and migration of non-small-cell lung cancer cells through activating TGF-β pathway and IL-6/JAK2/STAT3 pathway

High SNHG expression may predict a poor lung cancer prognosis based on a meta-analysis

BACKGROUND

An increasing number of small nucleolar RNA host genes (SNHGs) have been revealed to be dysregulated in lung cancer tissues, and abnormal expression of SNHGs is significantly correlated with the prognosis of lung cancer. The purpose of this study was to conduct a meta-analysis to explore the correlation between the expression level of SNHGs and the prognosis of lung cancer.

METHODS

A comprehensive search of six related databases was conducted to obtain relevant literature. Relevant information, such as overall survival (OS), progression-free survival (PFS), TNM stage, lymph node metastasis (LNM), and tumor size, was extracted. Hazard ratios (HRs) and 95% confidence intervals (CIs) were pooled to evaluate the relationship between SNHG expression and the survival outcome of lung cancers. Sensitivity and publication bias analyses were performed to explore the stability and reliability of the overall results.

RESULTS

Forty publications involving 2205 lung cancer patients were included in this meta-analysis. The pooled HR and 95% CI values indicated a significant positive association between high SNHG expression and poor OS (HR: 1.890, 95% CI: 1.595-2.185), disease-free survival (DFS) (HR: 2.31, 95% CI: 1.57-3.39) and progression-free survival (PFS) (HR: 2.01, 95% CI: 0.66-6.07). The pooled odds ratio (OR) and 95% CI values indicated that increased SNHG expression may be correlated with advanced TNM stage (OR: 1.509, 95% CI: 1.267-1.799), increase risk of distant lymph node metastasis (OR: 1.540, 95% CI: 1.298-1.828), and large tumor size (OR: 1.509, 95% CI: 1.245-1.829). Sensitivity analysis and publication bias results showed that each result had strong reliability and robustness, and there was no significant publication bias or other bias.

CONCLUSION

Most SNHGs are upregulated in lung cancer tissues, and high expression of SNHGs predicts poor survival outcomes in lung cancer. SNHGs may be potential prognostic markers and promising therapeutic targets.

Clinical Implication of E2F Transcription Factor 1 in Hepatocellular Carcinoma Tissues

Background: To date, the clinical management of advanced hepatocellular carcinoma (HCC) patients remains challenging and the mechanisms of E2F transcription factor 1 (E2F1) underlying HCC are obscure. Materials and Methods: Our study integrated datasets mined from several public databases to comprehensively understand the deregulated expression status of E2F1. Tissue microarrays and immunohistochemistry staining was used to validate E2F1 expression level. The prognostic value of E2F1 was assessed. In-depth subgroup analyses were implemented to compare the differentially expressed levels of E2F1 in HCC patients with various tumor stages. Functional enrichments were used to address the predominant targets of E2F1 and shedding light on their potential roles in HCC. Results: We confirmed the elevated expression of E2F1 in HCC. Subgroup analyses indicated that elevated E2F1 level was independent of various stages in HCC. E2F1 possessed moderate discriminatory capability in differentiating HCC patients from non-HCC controls. Elevated E2F1 correlated with Asian race, tumor classification, neoplasm histologic grade, eastern cancer oncology group, and plasma AFP levels. Furthermore, high E2F1 correlated with poor survival condition and pooled HR signified E2F1 as a risk factor for HCC. Enrichment analysis of differentially expressed genes, coexpressed genes, and putative targets of E2F1 emphasized the importance of cell cycle pathway, where CCNE1 and CCNA2 served as hub genes. Conclusions: We confirmed the upregulation of E2F1 and explored the prognostic value of E2F1 in HCC patients. Two putative targeted genes (CCNE1 and CCNA2) of E2F1 were identified for their potential roles in regulating cell cycle and promote antiapoptotic activity in HCC patients.

Role of Non-Coding RNAs in Hepatocellular Carcinoma Progression: From Classic to Novel Clinicopathogenetic Implications

Hepatocellular carcinoma (HCC) is a predominant malignancy with increasing incidences and mortalities worldwide. In Western countries, the progressive affirmation of Non-alcoholic Fatty Liver Disease (NAFLD) as the main chronic liver disorder in which HCC occurrence is appreciable even in non-cirrhotic stages, constitutes a real health emergency. In light of this, a further comprehension of molecular pathways supporting HCC onset and progression represents a current research challenge to achieve more tailored prognostic models and appropriate therapeutic approaches. RNA non-coding transcripts (ncRNAs) are involved in the regulation of several cancer-related processes, including HCC. When dysregulated, these molecules, conventionally classified as "small ncRNAs" (sncRNAs) and "long ncRNAs" (lncRNAs) have been reported to markedly influence HCC-related progression mechanisms. In this review, we describe the main dysregulated ncRNAs and the relative molecular pathways involved in HCC progression, analyzing their implications in certain etiologically related contexts, and their applicability in clinical practice as novel diagnostic, prognostic, and therapeutic tools. Finally, given the growing evidence supporting the immune system response, the oxidative stress-regulated mechanisms, and the gut microbiota composition as relevant emerging elements mutually influencing liver-cancerogenesis processes, we investigate the relationship of ncRNAs with this triad, shedding light on novel pathogenetic frontiers of HCC progression.

A comprehensive insight into the role of small nucleolar RNAs (snoRNAs) and SNHGs in human cancers

Long non-coding RNAs (lncRNAs), which comprise most non-coding RNAs (ncRNAs), have recently become a focus of cancer research. How many functional ncRNAs exist is still a matter of debate. Although insufficient evidence supports that most lncRNAs function as transcriptional by-products, it is widely known that an increasing number of lncRNAs play essential roles in cells. Small nucleolar RNAs (snoRNAs), 60-300 nucleotides in length, have been better studied than long non-coding RNAs (lncRNAs) and are predominantly present in the nucleolus. Most snoRNAs are encoded in introns of protein- and non-protein-coding genes called small nucleolar RNA host genes (SNHGs). In this article, we explore the biology and characteristics of SNHGs and their role in developing human malignancies. In addition, we provide an update on the ability of these snoRNAs to serve as prognostic and diagnostic variables in various forms of cancer.

The E2F1/MELTF axis fosters the progression of lung adenocarcinoma by regulating the Notch signaling pathway

BACKGROUND

Lung adenocarcinoma (LUAD) represents the predominant subtype of lung cancer. MELTF, an oncogene, exhibits high expression in various cancer tissues. Nevertheless, the precise role of MELTF in the progression of LUAD remains enigmatic. This work was devised to investigate the effect of MELTF on LUAD progression and its underlying mechanism.

METHODS

mRNA expression data of LUAD were from The Cancer Genome Atlas database, and the enrichment pathway of MELTF was analyzed. The upstream transcription factors of MELTF were predicted, and the correlation between MELTF and E2F1 as well as the expression of the two in LUAD tissues were dissected by bioinformatics. The expression of MELTF and E2F1 in LUAD tissues and cells was assayed by qRT-PCR. Effects of MELTF/E2F1 on proliferation, migration, and invasion of LUAD cells were tested by CCK-8, colony formation, and Transwell assays. The binding relationship between E2F1 and MELTF was estimated by dual-luciferase reporter gene assay and ChIP assay. Western blot was utilized to assay the expression of Notch signaling pathway-related proteins in different treatment groups.

RESULTS

Bioinformatics analysis and qRT-PCR results exhibited high expression of E2F1 and MELTF in LUAD tissues and cells, respectively. Dual-luciferase reporter gene assay and ChIP assay ascertained the binding of E2F1 to MELTF. MELTF was ascertained to enrich the Notch signaling pathway by bioinformatics means. In cell experiments, MELTF was shown to foster the malignant progression of LUAD cells and promoted the expression of NOTCH1 and HES1 proteins, but RO4929097 offset the effect of MELTF on cells. Rescue assay confirmed that E2F1 activated MELTF to promote LUAD progression via the Notch signaling pathway.

CONCLUSION

Together, our outcomes demonstrated that E2F1 fostered LUAD progression by activating MELTF via the Notch signaling activity. Hence, MELTF emerged as a feasible target for treating LUAD.

SnoRNA and lncSNHG: Advances of nucleolar small RNA host gene transcripts in anti-tumor immunity

The small nucleolar RNA host genes (SNHGs) are a group of genes that can be transcript into long non-coding RNA SNHG (lncSNHG) and further processed into small nucleolar RNAs (snoRNAs). Although lncSNHGs and snoRNAs are well established to play pivotal roles in tumorigenesis, how lncSNHGs and snoRNAs regulate the immune cell behavior and function to mediate anti-tumor immunity remains further illustrated. Certain immune cell types carry out distinct roles to participate in each step of tumorigenesis. It is particularly important to understand how lncSNHGs and snoRNAs regulate the immune cell function to manipulate anti-tumor immunity. Here, we discuss the expression, mechanism of action, and potential clinical relevance of lncSNHGs and snoRNAs in regulating different types of immune cells that are closely related to anti-tumor immunity. By uncovering the changes and roles of lncSNHGs and snoRNAs in different immune cells, we aim to provide a better understanding of how the transcripts of SNHGs participate in tumorigenesis from an immune perspective.

Roles of TGF‑β signalling pathway‑related lncRNAs in cancer (Review)

Long non-coding RNAs (lncRNAs) are a class of RNAs that are >200 nucleotides in length that do not have the ability to be translated into protein but are associated with numerous diseases, including cancer. The involvement of lncRNAs in the signalling of certain signalling pathways can promote tumour progression; these pathways include the transforming growth factor (TGF)-β signalling pathway, which is related to tumour development. The expression of lncRNAs in various tumour tissues is specific, and their interaction with the TGF-β signalling pathway indicates that they may serve as new tumour markers and therapeutic targets. The present review summarized the role of TGF-β pathway-associated lncRNAs in regulating tumorigenesis in different types of cancer and their effects on the TGF-β signalling pathway.

Prognostic signature of lipid metabolism associated LncRNAs predict prognosis and treatment of lung adenocarcinoma

BACKGROUND

Lung adenocarcinoma (LUAD) is the most predominant histological subtype of lung cancer. Abnormal lipid metabolism is closely related to the development of LUAD. LncRNAs are involved in the regulation of various lipid metabolism-related genes in various cancer cells including LUAD. Here, we aimed to identify lipid metabolism-related lncRNAs associated with LUAD prognosis and to propose a new prognostic signature.

METHODS

First, differentially expressed lncRNAs (DE-lncRNAs) from the TCGA-LUAD and the GSE31210 dataset were identified. Then the correlation analysis between DE-lncRNAs and lipid metabolism genes was performed to screen lipid metabolism-related lncRNAs. Cox regression analyses were performed in the training set to establish a prognostic model and the model was validated in the testing set and the validation set. Moreover, The role of this model in the underlying molecular mechanisms, immunotherapy, and chemotherapeutic drug sensitivity analysis was predicted by methods such as Gene Set Enrichment Analysis, immune infiltration, tumor mutational burden (TMB), neoantigen, Tumor Immune Dysfunction and Exclusion, chemosensitivity analysis between the high- and low-risk groups. The diagnostic ability of prognostic lncRNAs has also been validated. Finally, we validated the expression levels of selected prognostic lncRNAs by quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

The prognostic model was constructed based on four prognostic lncRNAs (LINC00857, EP300-AS1, TBX5-AS1, SNHG3) related to lipid metabolism. The receiver operating characteristic curve (ROC) and Kaplan Meier (KM) curves of the risk model showed their validity. The results of Gene Set Enrichment Analysis suggested that differentially expressed genes in high- and low-risk groups were mainly enriched in immune response and cell cycle. There statistical differences in TMB and neoantigen between high- and low-risk groups. Drug sensitivity analysis suggested that patients with low risk scores may have better chemotherapy outcomes. The results of qRT-PCR were suggesting that compared with the normal group, the expressions of EP300-AS1 and TBX5-AS1 were down-regulated in the tumor group, while the expressions of LINC00857 and SNHG3 were up-regulated. The four prognostic lncRNAs had good diagnostic capabilities, and the overall diagnostic model of the four prognostic lncRNAs was more effective.

CONCLUSION

A total of 4 prognostic lncRNAs related to lipid metabolism were obtained and an effective risk model was constructed.

MiR-124-3p Reduces Bone Mineral Density in Postmenopausal Osteoporosis Rats Through Regulating Signal Transducer and Activator of Transcription 3 Pathway

We aimed to study the effect of miR-124-3p on postmenopausal osteoporosis (POP) rats through regulating the signal transducer and activator of transcription 3 (STAT3) pathway. Rats were randomly divided into normal group, model group and miR-124-3p antagomir group. Enzyme-linked immunosorbent assay (ELISA) was performed to determine the levels of receptor activator of nuclear factor-κB (RANK) and osteoprotegerin (OPG). BMD of femur was significantly lower in model group and miR-124-3p antagomir group than that in normal group at 12 weeks after modeling, while it was significantly higher in miR-124-3p antagomir group than that in model group. Positive expression of BMP2 was obviously higher in miR-124-3p antagomir group than that in model group. Protein expression of p-STAT3 was evidently lower in miR-124-3p antagomir group than that in model group. Besides, POP rats have significantly increased level of miR-124-3p compared with that in normal group. In model group and miR-124-3p antagomir group, the content of OPG was remarkably lower, and the content of RANK was remarkably higher than those in normal group. In miR-124-3p antagomir group, the content of OPG was remarkably higher, and RANK was remarkably lower than those in model group. MiR-124-3p reduces BMD in POP rats through up-regulating the STAT3 pathway.

Establishment of Prognostic Signatures of N6-Methyladenosine-Related lncRNAs and Their Potential Functions in Hepatocellular Carcinoma Patients

N6-methyladenosine (m6a)-related mRNAs and lncRNAs have been explored for their functions in several cancers. The present study aimed to identify potential signatures of m6a-related lncRNAs in hepatocellular carcinoma (HCC). We downloaded the expression and clinical data from The Cancer Genome Atlas (TCGA) database. The interacted mRNAs and lncRNAs, prognosis-related lncRNAs, potential metabolic pathways of lncRNAs, immune infiltration of various cells, and CD274 (PD-L1) -related lncRNAs were analyzed. Then, in vitro experiments explored the role of AC012073.1 (LOC105377626) in HCC cell lines. We found that candidate 14 lncRNA signatures play functions in HCC maybe by affecting immune infiltration, cell cycle, Notch signaling pathway, etc. LncRNA AC012073.1 (LOC105377626) functions as oncogenic roles in affecting HCC prognosis.

Quercetin encapsulated in Folic Acid-Modified Liposomes is therapeutic against osteosarcoma by non-Covalent binding to the JH2 Domain of JAK2 Via the JAK2-STAT3-PDL1

Osteosarcoma (OS) is a malignant solid tumor prone to lung metastasis that occurs in adolescents aged 15-19 years. Neoadjuvant chemotherapy and surgical treatment aimed at curing OS have gained limited progress over the last 30 years. Exploring new effective second-line therapies for OS patients is a serious challenge for researchers. Quercetin, a multiple biologically active polyphenolic flavonoid, has been used in tumor therapy. However, the exact mechanism of quercetin is still unknown, which limits the application of quercetin. In the current study, we found that quercetin could inhibit JAK2 through the JH2 domain in a non-covalent manner, resulting in the inhibition of OS proliferation and immune escape via the JAK2-STAT3-PD-L1 signaling axis. More importantly, to overcome the shortcomings of quercetin, including low water solubility and low oral availability, we encapsulated it with folic acid-modified liposomes. The transportation of quercetin by folic acid-modified liposomes may provide a feasible strategy to cure OS.

Long non-coding RNAs and exosomal lncRNAs: Potential functions in lung cancer progression, drug resistance and tumor microenvironment remodeling

Among the different kinds of tumors threatening human life, lung cancer is one that is commonly observed in both males and females. The aggressive behavior of lung cancer and interactions occurring in tumor microenvironment enhances the malignancy of this tumor. The lung tumor cells have demonstrated capacity in developing chemo- and radio-resistance. LncRNAs are a category of non-coding RNAs that do not encode proteins, but their aberrant expression is responsible for tumor development, especially lung cancer. In the present review, we focus on both lncRNAs and exosomal lncRNAs in lung cancer, and their ability in regulating proliferation and metastasis. Cell cycle progression and molecular mechanisms related to lung cancer metastasis such as EMT and MMPs are regulated by lncRNAs. LncRNAs interact with miRNAs, STAT, Wnt, EZH2, PTEN and PI3K/Akt signaling pathways to affect progression of lung cancer cells. LncRNAs demonstrate both tumor-suppressor and tumor-promoting functions in lung cancer. They can be considered as biomarkers in lung cancer and especially exosomal lncRNAs present in body fluids are potential tools for minimally invasive diagnosis. Furthermore, we discuss regulation of lncRNAs by anti-cancer drugs and genetic tools as well as the role of these factors in therapy response of lung cancer cells.

LINC01806 mediated by STAT1 promotes cell proliferation, migration, invasion, and stemness in non-small cell lung cancer through Notch signaling by miR-4428/NOTCH2 axis

Background

Non-small cell lung cancer (NSCLC), the most primary lung cancer subtype, threatens human health globally. Long non-coding RNAs (lncRNAs) have been uncovered to affect multiple cancers progression. Nevertheless, the specific function of long intergenic non-protein coding RNA 1806 (LINC01806) in NSCLC remains elusive.

Methods

RT-qPCR and western blot were involved in this study. The influence of LINC01806 on NSCLC was assessed by in vitro and in vivo assays. Via ChIP, RNA pull down, RIP, and luciferase reporter assays, the in-depth cellular mechanisms of LINC01806 in NSCLC were explored.

Results

LINC01806 expression was high in NSCLC cell lines. Functionally, LINC01806 knockdown impeded cell proliferation, migration, invasion, and stemness, along with tumor growth. As for its mechanism, signal transducer and activator of transcription 1 (STAT1) activated LINC01806 transcription in NSCLC. Furthermore, LINC01806 sequestered microRNA-4428 (miR-4428) to enhance notch receptor 2 (NOTCH2) expression, thus activating Notch signaling pathway. Finally, in vitro and in vivo assays jointly validated that LINC01806 exerted its function in NSCLC development via miR-4428/NOTCH2 pathway.

Conclusion

LINC01806 enhanced NOTCH2 expression to stimulate Notch signaling via sponging miR-4428, thereby facilitating NSCLC progression, which provided a novel mechanism for NSCLC therapeutic approaches.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02560-8.

lncRNA RP11-10A14.5: a potential prognosis biomarker for LUAD through regulation on proliferation and metastasis

Lung cancer is the malignancy most commonly seen worldwide. Emerging evidences indicated that lncRNAs may serve as a prognosis marker and play important role in NSCLC tumor biology. In this work, we analyzed the prognosis value of RP11-10A14.5 using TCGA and GEPIA database and expression profiles using PCR and FISH assay. The biological roles of RP11-10A14.5 in cell growth and invasion were determined by in vitro and in vivo experiments. Expression of RP11-10A14.5 is correlated with increased clinical stage and poor survival prognosis. In vitro experiments revealed that RP11-10A14.5 was widely expressed in lung cancer cell lines and mainly distributed in the cytoplasm and enhanced the growth, invasion and migration ability of NSCLC cell lines. Immunofluorescence assay suggested that RP11-10A14.5 may promote EMT by downregulating E-cadherin and upregulating N-cadherin and Vimentin. Flow cytometry results suggested that RP11-10A14.5 did not significantly affect cell cycle function, but could significantly inhibit apoptosis which may further enhance metastasis cell survival. In conclusion, RP11-10A14.5 is associated with clinical stage and poor survival outcome, may serve as a diagnosis and prognosis predictor for LUAD. Further, RP11-10A14.5 could promote LUAD cell growth and metastasis.

Small nucleolar RNA host gene 3 functions as a novel biomarker in liver cancer and other tumour progression

Cancer has become the most life-threatening disease in the world. Mutations in and aberrant expression of genes encoding proteins and mutations in noncoding RNAs, especially long noncoding RNAs (lncRNAs), have significant effects in human cancers. LncRNAs have no protein-coding ability but function extensively in numerous physiological and pathological processes. Small nucleolar RNA host gene 3 (SNHG3) is a novel lncRNA and has been reported to be differentially expressed in various tumors, such as liver cancer, gastric cancer, and glioma. However, the interaction mechanisms for the regulation between SNHG3 and tumor progression are poorly understood. In this review, we summarize the results of SNHG3 studies in humans, animal models, and cells to underline the expression and role of SNHG3 in cancer. SNHG3 expression is upregulated in most tumors and is detrimental to patient prognosis. SNHG3 expression in lung adenocarcinoma remains controversial. Concurrently, SNHG3 affects oncogenes and tumor suppressor genes through various mechanisms, including competing endogenous RNA effects. A deeper understanding of the contribution of SNHG3 in clinical applications and tumor development may provide a new target for cancer diagnosis and treatment.

LncRNA SNHG3 Facilitates the Malignant Phenotype of Cholangiocarcinoma Cells via the miR-3173-5p/ERG Axis

BACKGROUND

Long noncoding RNA (lncRNA) small nucleolar RNA host gene 3 (SNHG3) is an oncogenic lncRNA that has been reported in many cancers, but the role of SNHG3 in cholangiocarcinoma (CCA) remains largely unknown. Bioinformatic analysis revealed a regulatory relationship among SNHG3, miR-3173-5p, and ERG. miR-3173-5p is a tumour suppressive miRNA, while ERG is an oncogene. In the present study, we focused on the regulatory effects and molecular mechanisms of SNHG3 in CCA.

METHOD

The expression of SNHG3 and miR-3173-5p was evaluated using qRT-PCR analysis. Knockdown of SNHG3 was achieved by shRNA. Cell viability was assessed by MTT assay. Migration and invasion were determined by Transwell assay. Flow cytometry was used to assess cell apoptosis. Western blots were applied to quantify protein levels. Furthermore, using RNA pulldown and dual luciferase assays, the interactions between SNHG3 and miR-3173-5p and between miR-3173-5p and ERG in CCA cells were validated.

RESULTS

SNHG3 was significantly upregulated in CCA cells compared with normal human intrahepatic biliary epithelial cells. Knockdown of SNHG3 inhibited the proliferation and migration of CCA cells. Mechanistically, SNHG3-sponged miR-3173-5p, thus releasing the repression of ERG by miR-3173-5p. Rescue experiments showed that the miR-3173-5p/ERG axis mediated the oncogenic effect of SNHG3.

CONCLUSION

Taken together, our data suggest that SNHG3 is a pleiotropic oncogenic lncRNA in CCA. Knockdown of SNHG3 expression suppressed malignant phenotypes in CCA cells via the miR-3173-5p/ERG axis.

Integrated Analysis of lncRNA and mRNA Expression Profiles Indicates Age-Related Changes in Meniscus

Little has been known about the role of long non-coding RNA (lncRNA) involves in change of aged meniscus. Microarray analyses were performed to identify lncRNAs and mRNAs expression profiles of meniscus in young and aging adults and apple bioinformatics methods to analyse their potential roles. The differentially expressed (DE) lncRNAs and mRNAs were confirmed by qRT-PCR. A total of 1608 DE lncRNAs and 1809 DE mRNAs were identified. Functional and pathway enrichment analyses of all DE mRNAs showed that DE mRNAs were mainly involved in the TGF-beta, Wnt, Hippo, PI3K-Akt signaling pathway. The expressions of TNFRSF11B and BMP2 were significantly upregulated in aging group. LASSO logistic regression analysis of the DE lncRNAs revealed four lncRNAs (AC124312.5, HCG11, POC1B-AS1, and AP001011.1) that were associated with meniscus degradation. CNC analysis demonstrated that AP001011 inhibited the expression of TNFRSF11B and AC1243125 upregulated the expression of TNFRSF11B. CeRNA analysis suggested that POC1B-AS1 regulates the expression of BMP2 by sponging miR 130a-3p, miR136-5p, miR 18a-3p, and miR 608. Furthermore, subcellular localization and m⁶A modification sites prediction analysis of these four lncRNAs was performed. These data lay a foundation for extensive studies on the role of lncRNAs in change of aged meniscus.

Potential diagnostic and prognostic value of the long non-coding RNA SNHG3 in human cancers: A systematic review and meta-analysis

BACKGROUND

Small nucleolar RNA host gene 3 (SNHG3), as a novel long non-coding RNA (lncRNA) participates in the oncogenic processes of various cancers. We combined a systematic review and a meta-analysis to assess the potential role of SNHG3 as a pan-cancer marker for cancer diagnosis and prognosis.

METHODS

Our study comprehensively searched for SNHG3 expression profiling studies from PubMed, Web of Science, Excerpta Medica Database (EMBASE), Cochrane Library, Google Scholar, and The Cancer Genome Atlas (TCGA). The diagnostic capacity of SNHG3 for all cancers in TCGA database was evaluated from the perspective of pooled sensitivity, specificity, diagnostic odds ratio (DOR), area under the curve (AUC) of the summary receiver operating characteristic (sROC) curve. Also, this research studied the correlation of SNHG3 expression and the overall survival to access its prognostic value.

RESULTS

A sum total of 11,888 cancer patients and 730 controls from 44 eligible studies were enrolled in this integrated analysis. In TCGA database, SNHG3 was significantly upregulated in most types of cancers (16/33, 48%). The pooled sensitivity, specificity, and DOR with 95% CIs was 0.72 (95% CI: 0.60-0.82), 0.87 (95% CI: 0.84-0.90), and 18 (95% CI: 11-30), respectively. Similarly, the AUC of the sROC curve was 0.89 (95% CI: 0.86-0.92), indicating SNHG3 was highly conserved as a diagnosis biomarker. Additionally, SNHG3 overexpression significantly deteriorated the overall survival of cancer patients (pooled HR = 1.28, 95% CI:1.11-1.48; P < 0.05).

CONCLUSIONS

These findings suggest that the lncRNA SNHG3 could serve as a promising diagnostic and prognostic biomarker.

N6-methyladenosine-induced SVIL antisense RNA 1 restrains lung adenocarcinoma cell proliferation by destabilizing E2F1

Accumulating evidence indicates that N6-methyladenosine (m6A) and long noncoding RNAs (lncRNAs) play crucial roles in cancer development. However, the biological roles of m6A and lncRNAs in lung cancer tumorigenesis are largely unknown. In this study, SVIL antisense RNA 1 (SVIL-AS1) was downregulated in lung adenocarcinoma (LUAD) tissues and was associated with a favorable prognosis in patients with LUAD. SVIL-AS1 overexpression suppressed LUAD cell proliferation and blocked cell cycle arrest. Mechanistically, METTL3 increased the m6A modification and transcript stability of SVIL-AS1. The enhanced SVIL-AS1 expression mediated by METTL3 suppressed E2F1 and E2F1-target genes. Moreover, SVIL-AS1 accelerated E2F1 degradation. The reduction in cell proliferation induced by SVIL-AS1 overexpression could be rescued by E2F1 overexpression or METTL3 knockdown. In conclusion, our work demonstrated the role and mechanism of METTL3-induced SVIL-AS1 in LUAD, which connects m6A and lncRNA in lung cancer carcinogenesis.

High expression of small nucleolar RNA host gene 3 predicts poor prognosis and promotes bone metastasis in prostate cancer by activating transforming growth factor-beta signaling

Bone metastasis is closely related to tumor death in prostate cancer (PC). Long noncoding RNA small nucleolar RNA host gene 3 (SNHG3) has been implicated in the initiation and progression of multiple human cancers. Nevertheless, the biological function of SNHG3 in PC has not been elucidated. Our results indicated that SNHG3 was upregulated in bone metastasis-positive PC tissues compared to bone metastasis-negative PC tissues and adjacent normal tissues. High expression of SNHG3 indicates advanced clinicopathological features and predicts poor prognosis in patients with PC. Meanwhile, SNHG3 knockdown suppressed the proliferation, migration, and invasion abilities of PC cells and inhibited PC cell metastasis to the bone. Mechanistically, SNHG3 enhanced the expression of transforming growth factor beta receptor 1 (TGFBR1) and activated transforming growth factor-Beta (TGF-β) signaling by targeting miR-214-3p. Our study demonstrated the novel role of the SNHG3/miR-214-3p/TGF-β axis in tumor growth and bone metastasis in PC, indicating that SNHG3 may act as a biomarker and promising therapeutic target against PC.

A diagnostic and prognostic value of blood-based circulating long non-coding RNAs in Thyroid, Pancreatic and Ovarian Cancer

Several studies have demonstrated the potential of circulating long non-coding RNAs (lncRNAs) as promising cancer biomarkers. Herein, we addressed the regulatory role of circulating lncRNAs and their potential value as diagnostic/prognostic markers for thyroid, pancreatic and ovarian cancers. Furthermore, we analyzed and measured the clinical implications and association of lncRNAs with sensitivity, specificity, and area under the ROC curve (AUC). Based on our meta-analysis, we found that GAS8-AS1 could discriminate thyroid cancer from non-cancer and other cancers with higher accuracy (AUC = 0.746; sensitivity = 61.70%, and specificity = 90.00%). Similarly, for ovarian cancer, lncRNA RP5-837J1.2 was found to have ideal diagnostic potential with critical clinical specifications of AUC = 0.996; sensitivity = 97.30% and specificity = 94.60%. Whereas we could not find any lncRNA having high diagnostic/prognostic efficiency in pancreatic cancer. We believe that lncRNAs mentioned above may explore clinical settings for the diagnosis and prognosis of cancer patients.

DNA-methylation-induced silencing of DIO3OS drives non-small cell lung cancer progression via activating hnRNPK-MYC-CDC25A axis

DNA methylation is a class of epigenetic modification manner, which is responsible for the inactivation of various tumor suppressors. Recently, long non-coding RNAs (lncRNAs) were revealed to be implicated in a variety of malignancies, including non-small cell lung cancer (NSCLC). However, the contributions of lncRNAs to DNA-methylation-induced oncogenic effects in NSCLC remain largely unknown. In this study, we identified a DNA-methylation-repressed lncRNA DIO3 opposite strand upstream RNA (DIO3OS) in NSCLC. DIO3OS is downregulated in NSCLC, and its low expression is related to poor prognosis. Ectopic expression of DIO3OS repressed NSCLC cell growth and motility and promoted NSCLC cell apoptosis in vitro. DIO3OS also repressed NSCLC tumorigenesis and metastasis in vivo. DIO3OS knockdown exhibited opposite biological effects. DIO3OS competitively bound heterogeneous nuclear ribonucleoprotein K (hnRNPK), repressed the binding of hnRNPK to MYC DNA and MYC mRNA, reduced the promoting roles of hnRNPK on MYC transcription and translation, led to the repression of MYC transcription and translation, and therefore remarkably decreased the expression of MYC and CDC25A, a downstream target of MYC. Additionally, depletion of hnRNPK blocked the tumor-suppressive roles of DIO3OS in NSCLC. In conclusion, these findings identified DIO3OS as an important protective factor against NSCLC via modulating hnRNPK-MYC-CDC25A axis.

LncRNA SNHG3 promotes gastric cancer cell proliferation and metastasis by regulating the miR-139-5p/MYB axis

The long non-coding RNA (lncRNA) SNHG3 has been shown to play oncogenic roles in several cancer types, but the mechanisms underlying its activity are poorly understood. In this study, we aimed to explore the clinical relevance and mechanistic role of SNHG3 in gastric cancer (GC). We found that SNHG3 expression in GC cell lines and tissues was significantly increased, and the upregulation of this lncRNA was correlated with tumor clinical stage and decreased patient survival. Knocking down SNHG3 in GC cells impaired the proliferative, migratory, and invasive activity in vitro and constrained in vivo GC xenograft tumor growth. Mechanistically, SNHG3 was found to bind and sequester miR-139-5p, thereby indirectly promoting the upregulation of the miR-139-5p target gene MYB. These data demonstrated that SNHG3 functions in an oncogenic manner to drive GC proliferation, migration, and invasion by regulating the miR-139-5p/MYB axis.

LncRNA-ENST00000556926 regulates the proliferation, apoptosis and mRNA transcriptome of malignant-transformed BEAS-2B cells induced by coal tar pitch

As a byproduct of coal tar distillation, coal tar pitch (CTP) has been proven to be carcinogenic to human. However, the mechanisms of lung cancer induced by CTP are still unclear. It has been shown that long non-coding RNAs (LncRNAs) play an important role in the development of human cancers. This study aims to investigate the effect of LncRNA-ENST00000556926 on malignant-transformed human bronchial epithelial (BAES-2B) cells induced by coal tar pitch extracts (CTPE). In this study, BEAS-2B cells were treated with 2.4 μg/ml of CTPE for 72 h and then passaged; and the cells were treated 4 times in the same procedure, then passaged until passage 30 (CTPE30). Cell counting kit-8 (CCK-8) assay was used to detect cell viability, then cell cycle and apoptosis were analyzed by flow cytometry, and transcriptome sequencing analysis was used to detect differentially expressed mRNAs after interference of ENST00000556926. The results indicated that the expression of ENST00000556926 in CTPE30 group was significantly higher compared with control group. Furthermore, after interfering the expression of ENST00000556926, cell viability was inhibited, and cell cycle was arrested while apoptosis of malignant-transformed BEAS-2B cells was promoted. Moreover, a total of 159 differentially expressed mRNAs were screened out after interference of ENST00000556926, including 62 up-regulated mRNAs and 97 down-regulated mRNAs. In addition, knockdown of ENST00000556926 decreased the expression of thioredoxin domain containing 5 (TXNDC5) and FOXD1. In conclusion, LncRNA-ENST00000556926 could regulate the proliferation, apoptosis and mRNA transcriptome of malignant-transformed BEAS-2B cells induced by CTP, which may provide a novel treatment strategy for lung cancer.

CircRPPH1 promotes cell proliferation, migration and invasion of non-small cell lung cancer (NSCLC) via the PI3K/AKT and JAK2/STAT3 signaling axes

Non-small cell lung cancer (NSCLC) has markedly increased morbidity and mortality rate worldwide. Circular RNAs (circRNAs) were shown to regulate NSCLC progression. But, the underlying pathways of the circRPPH1-mediated regulation of NSCLC still need further exploration. We evaluated circRPPH1 levels in NSCLC tissues and cell lines via qRT-RCR. Moreover, using ectopic plasmid incorporation and siRNA assays, we analyzed the circRPPH1-mediated regulation of cell proliferation (CP), migration (CM), and invasion (CI) in NSCLC cell lines (H1975 and A549 cells), using CCK-8, colony forming, scratch wound, and transwell assays, respectively. CircRPPH1 levels were remarkably high in the NSCLC tissues and cell lines. The transfection experiments showed that circRPPH1 overexpression was able to promote CP, CM and CI of NSCLC cells, while CP, CM and CI were significantly restrained by the knockdown of circRPPH1. We also displayed that circRPPH1 knockdown suppressed the cell progression via inactivating the PI3K/AKT and JAK2/STAT3 signaling axes. Subsequently, in vivo experiment in nude mice was demonstrated that the inhibition of circRPPH1 could reduce the tumor growth of NSCLC. circRPPH1 may accelerate the growth and metastasis of NSCLC, in culture conditions and in animal models, by stimulating the PI3K/AKT and JAK2/STAT3 signaling axes, thus promoting the development of NSCLC.

Long non-coding RNA SNHG3 promotes the progression of clear cell renal cell carcinoma via regulating BIRC5 expression

Background

Research has shown that the progression of clear cell renal cell carcinoma (ccRCC) is modulated by long non-coding RNAs (lncRNAs). However, the roles of specific lncRNAs in the malignancy of ccRCC are still unknown.

Methods

TCGA and GSE66272 datasets were used to predict differentially expressed genes (DEGs) in ccRCC. ENCORI database was employed to display BIRC5 miRNA network and potential lncRNA interactions for miRNAs. KM plotter and correlation analyses were performed to identify the overall survival (OS)- and BIRC5-related miRNAs. Quantitative real-time PCR (qRT-PCR) was used to verify the BIRC5 mRNA in the seventy paired clinical samples of ccRCC tissues. The ccRCC A498 and 786-O were individually transfected with lncRNA SNHG3 and LINC00997 and then western blotting was used to detect the BIRC5 protein expression. The Dual-luciferase reporter assay was used to examine the regulatory interaction between lncRNA SNHG3 and microRNA (miRNA/miR)-10b-5p.

Results

BICR5 is associated with the progression of ccRCC. The two novel lncRNAs (LINC00997, SNHG3) were up-regulated in ccRCC tissues and positively with the BICR5 protein expression. However, Suppressing SNHG3 expression reduced BIRC5 protein expression compared with the LINC00997, most importantly, Suppressing SNHG3 expression suppressed tumor progression in vitro. In addition, SNHG3 promotes the expression of BIRC5 protein by sponging microRNA-10b-5p.

Conclusions

Our findings suggest that SNHG3 plays a vital role in promoting ccRCC via the microRNA-10b-5p/BIRC5 axis and may serve as a novel therapeutic target for the treatment of patients with ccRCC.

LINC01234 aggravates cell growth and migration of triple-negative breast cancer by activating the Wnt pathway

Triple-negative breast cancer (TNBC) is a common cancer with increasing incidence and mortality in female. Increasing studies have revealed that long noncoding RNAs (lncRNAs) are novel molecules regulating tumors. Long intergenic non-protein coding RNA 1234 (LINC01234) has been demonstrated to function as an oncogene in several tumors. However, the role of LINC01234 in TNBC remains unelucidated. Herein, RT-qPCR showed that LINC01234 expression was upregulated in both TNBC tissues and cell lines. Functionally, knockdown of LINC01234 suppressed proliferation, migration, invasion, epithelial-mesenchymal transition (EMT) process, and promoted apoptosis in TNBC cells. Xenograft mouse models revealed that LINC01234 downregulation inhibited TNBC tumor growth in vivo. Furthermore, LINC01234 was transcriptionally elevated by Sp1 transcription factor (SP1) in TNBC cells. Mechanistically, LINC01234 interacted with miR-525-5p and miR-525-5p targeted MEIS2. Rescue assays manifested that MEIS2 overexpression rescued the cellular processes inhibited by silenced LINC01234. Moreover, we validated that LINC01234 regulated the activation of the Wnt pathway through modulating MEIS2 in TNBC cells. In conclusion, LINC01234 aggravated TNBC cell growth, migration, invasion and EMT by modulating the miR-525-5p/MEIS2 axis and activating the Wnt/β-catenin signaling pathway.

E2F transcription factor 1 (E2F1) promotes the transforming growth factor TGF-β1 induced human cardiac fibroblasts differentiation through promoting the transcription of CCNE2 gene

The differentiation of cardiac fibroblast to myofibroblast is the key process of cardiac fibrosis. In the study, we aimed to determine the function of E2F Transcription Factor 1 (E2F1) in human cardiac fibroblasts (HCFs) differentiation, search for its downstream genes and elucidate the function of them in HCFs differentiation. As a result, we found that E2F1 was up-regulated in TGF-β1-induced HCFs differentiation. Silencing the expression of E2F1 by siRNA in HCFs, we found that the expression of differentiation-related genes (Collagen-1, α-Smooth muscle actin, and Fibronectin-1) was significantly suppressed, combining with proliferation and migration assay, we determined that HCFs differentiation was decreased. Luciferase report assay and immunoprecipitation proved that the oncogene CCNE2 was a direct target gene of E2F1, overexpression of CCNE2 was found in differentiated HCFs, silencing the expression of CCNE2 by siRNA decreased HCFs differentiation. Our research suggested that E2F1 and its downstream target gene CCNE2 play a vital role in TGF-β1-induced HCFs differentiation, thus E2F1 and CCNE2 may be a potential therapeutic target for cardiac fibrosis.

Revisiting Lung Cancer Metastasis: Insight From the Functions of Long Non-coding RNAs

Globally, lung cancer is the most common cause of cancer-related deaths. After diagnosis at all stages, <7% of patients survive for 10 years. Thus, diagnosis at later stages and the lack of effective and personalized drugs reflect a significant need to better understand the mechanisms underpinning lung cancer progression. Metastasis should be responsible for the high lethality and recurrence rates seen in lung cancer. Metastasis depends on multiple crucial steps, including epithelial–mesenchymal transition, vascular remodeling, and colonization. Therefore, in-depth investigations of metastatic molecular mechanisms can provide valuable insights for lung cancer treatment. Recently, long noncoding RNAs (lncRNAs) have attracted considerable attention owing to their complex roles in cancer progression. In lung cancer, multiple lncRNAs have been reported to regulate metastasis. In this review, we highlight the major molecular mechanisms underlying lncRNA-mediated regulation of lung cancer metastasis, including (1) lncRNAs acting as competing endogenous RNAs, (2) lncRNAs regulating the transduction of several signal pathways, and (3) lncRNA coordination with enhancer of zeste homolog 2. Thus, lncRNAs appear to execute their functions on lung cancer metastasis by regulating angiogenesis, autophagy, aerobic glycolysis, and immune escape. However, more comprehensive studies are required to characterize these lncRNA regulatory networks in lung cancer metastasis, which can provide promising and innovative novel therapeutic strategies to combat this disease.

The Tyrosine Kinase-Driven Networks of Novel Long Non-coding RNAs and Their Molecular Targets in Myeloproliferative Neoplasms

Recent research has focused on the mechanisms by which long non-coding RNAs (lncRNAs) modulate diverse cellular processes such as tumorigenesis. However, the functional characteristics of these non-coding elements in the genome are poorly understood at present. In this study, we have explored several mechanisms that involve the novel lncRNA and microRNA (miRNA) axis participating in modulation of drug response and the tumor microenvironment of myeloproliferative neoplasms (MPNs). We identified novel lncRNAs via mRNA sequencing that was applied to leukemic cell lines derived from BCR-ABL1-positive and JAK2-mutant MPNs under treatment with therapeutic tyrosine kinase inhibitors (TKI). The expression and sequence of novel LNC000093 were further validated in both leukemic cells and normal primary and pluripotent cells isolated from human blood, including samples from patients with chronic myelogenous leukemia (CML). Downregulation of LNC000093 was validated in TKI-resistant CML while a converse expression pattern was observed in blood cells isolated from TKI-sensitive CML cases. In addition to BCR-ABL1-positive CML cells, the driver mutation JAK2-V617F-regulated lncRNA BANCR axis was further identified in BCR-ABL1-negative MPNs. Further genome-wide validation using MPN patient specimens identified 23 unique copy number variants including the 7 differentially expressed lncRNAs from our database. The newly identified LNC000093 served as a competitive endogenous RNA for miR-675-5p and reversed the imatinib resistance in CML cells through regulating RUNX1 expression. The extrinsic function of LNC000093 in exosomal H19/miR-675-induced modulation for the microenvironment was also determined with significant effect on VEGF expression.

Screening Prognosis-Related lncRNAs Based on WGCNA to Establish a New Risk Score for Predicting Prognosis in Patients with Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) remains an important cause of cancer death. The molecular mechanism of hepatocarcinogenesis and prognostic factors of HCC have not been completely uncovered.

METHODS

In this study, we screened out differentially expressed lncRNAs (DE lncRNAs), miRNAs (DE miRNAs), and mRNAs (DE mRNAs) by comparing the gene expression of HCC and normal tissue in The Cancer Genome Atlas (TCGA) database. DE mRNAs were used to perform Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Then, the miRNA and lncRNA/mRNA modules that were most closely related to the survival time of patients with HCC were screened to construct a competitive endogenous RNA (ceRNA) network by weighted gene coexpression network analysis (WGCNA). Moreover, univariable Cox regression and Kaplan-Meier curve analyses of DE lncRNAs and DE mRNAs were conducted. Finally, the lasso-penalized Cox regression analysis and nomogram model were used to establish a new risk scoring system and predict the prognosis of patients with liver cancer. The expression of survival-related DE lncRNAs was verified by qRT-PCR.

RESULTS

A total of 1896 DEmRNAs, 330 DElncRNAs, and 76 DEmiRNAs were identified in HCC and normal tissue samples. Then, the turquoise miRNA and turquoise lncRNA/mRNA modules that were most closely related to the survival time of patients with HCC were screened to construct a ceRNA network by WGCNA. In this ceRNA network, there were 566 lncRNA-miRNA-mRNA regulatory pairs, including 30 upregulated lncRNAs, 16 downregulated miRNAs, and 75 upregulated mRNAs. Moreover, we screened out 19 lncRNAs and 14 hub mRNAs related to prognosis from this ceRNA network by univariable Cox regression and Kaplan-Meier curve analyses. Finally, a new risk scoring system was established by selecting the optimal risk lncRNAs from the 19 prognosis-related lncRNAs through lasso-penalized Cox regression analysis. In addition, we established a nomogram model consisting of independent prognostic factors to predict the survival rate of HCC patients. Finally, the correlation between the risk score and immune cell infiltration and gene set enrichment analysis were determined.

CONCLUSIONS

In conclusion, the results may provide potential biomarkers or therapeutic targets for HCC and the establishment of the new risk scoring system and nomogram model provides the new perspective for predicting the prognosis of HCC.

Cucurbitacin B enhances apoptosis in gefitinib resistant non‑small cell lung cancer by modulating the miR‑17‑5p/STAT3 axis

Tyrosine kinase inhibitors, such as gefitinib, are currently widely used as targeted therapeutics for non-small cell lung cancer (NSCLC). Although drug resistance has become a major obstacle to successful treatment, mechanisms underlying resistance to gefitinib remain unclear. Therefore, the present study aimed to investigate the impact of adjunctive cucurbitacin B (CuB) on gefitinib resistance (GR) in the PC9 cell line, including identifying underlying mechanisms. Reverse transcription-quantitative PCR demonstrated significant downregulation of microRNA (miR)-17-5p expression in GR PC9 cells (PC9/GR), and this could be reversed by CuB. During combination treatment with CuB and gefitinib at IC₂₅, PC9/GR cell proliferation was downregulated, and apoptosis was upregulated. The presence of a miR-17-5p inhibitor negated the effects of CuB and gefitinib, whereas the presence of a miR-17-5p mimic enhanced them. Luciferase assays demonstrated that the hypothetical target gene, signal transducer and activator of transcription 3 (STAT3), was directly targeted by miR-17-5p. Moreover, significant elevation of the STAT3 protein and phosphorylation levels in PC9/GR cells was reversed by the addition of CuB, despite a lack of change in STAT3 transcription level. During combined treatment with CuB and gefitinib at IC₂₅, the STAT3 protein expression was negatively associated with the expression of miR-17-5p. Overexpression of STAT3 increased proliferation and decreased apoptosis and the protein levels of apoptosis-related factors cleaved caspase-3 and cleaved caspase-9 of PC9/GR cells. Findings indicated that STAT3 protein and phosphorylation levels became elevated in response to gefitinib, and that CuB-induced miR-17-5p expression led to STAT3 degradation, thereby ameliorating GR. In summary, CuB reduced the proliferation of GR PC9 cells by modulating the miR-17-5p/STAT3 axis, and may represent a promising potential novel strategy for the reversal of GR.

Construction of Novel lncRNA-miRNA-mRNA Network Associated With Recurrence and Identification of Immune-Related Potential Regulatory Axis in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant diseases globally. Despite continuous improvement of treatment methods, high postoperative recurrence rate remains an urgent problem. In order to determine the mechanism underlying recurrence of liver cancer and identify prognostic genes, data from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) were integrated and analyzed. Differentially expressed genes (DEGs) between HCC tissue and normal liver tissue were identified, and a protein–protein interaction network was constructed to find hub genes. Clinical correlation analysis and disease-free survival (DFS) analysis were performed using the R language and GEPIA to identify relapse-related genes. Correlation analysis was used to identify a potential regulatory axis. Dual-luciferase reporter gene assay was used to confirm the reliability of the long non-coding RNA (lncRNA)–microRNA (miRNA)–mRNA regulatory axis. Immune infiltration analysis was performed using the TIMER database. Correlations between immune gene markers and ASF1B were verified using quantitative real-time polymerase chain reaction (RT-qPCR). In this work, we found that nine lncRNAs and five mRNAs were significantly overexpressed in HCC tissues from patients with recurrence. SNHG3, LINC00205, ASF1B, AURKB, CCNB1, CDKN3, and DTL were also closely related to HCC grade and stage. Survival analysis showed that these seven DEGs were significantly correlated with poor DFS. Correlation analysis identified SNHG3–miR-214-3p–ASF1B as a potential regulatory axis. Dual-luciferase reporter gene assay showed that SNHG3 and ASF1B directly bound to miR-214-3p. ASF1B was negatively regulated by miRNA-214-3p, and overexpression of SNHG3 could inhibit the expression of miRNA-214-3p. In addition, ASF1B was positively correlated with immune infiltration. A reduction in ASF1B could markedly inhibit the expression of CD86, CD8, STAT1, STAT4, CD68, and PD1 in HCC cells. Flow cytometry showed that SNHG3 promoted the PD-1 expression by regulating ASF1B. Meanwhile, elevated ASF1B predicted poor prognosis of HCC patients in subgroups with decreased B cells, CD8+ T cells, or neutrophils, and those with enriched CD4+ T cells. In conclusion, we found that a novel lncRNA SNHG3/miR-214-3p/ASF1B axis could promote the recurrence of HCC by regulating immune infiltration.

[Role of long noncoding RNA SNHG3 in regulating proliferation, migration and invasion of cervical cancer SiHa cells]

OBJECTIVE

To investigate the regulatory role of the long non-coding RNA (lncRNA) small nucleolar host gene 3 (SNHG3) in proliferation, migration and invasion of human cervical cancer cell line SiHa.

OBJECTIVE

Array data were retrieved from GEO database to analyze the expression levels of SNHG3 in cervical cancer and adjacent normal tissues. SiHa cells were transfected with a small interfering RNA (siRNA) targeting SNHG3, and the changes in the transcriptional levels of lncRNA SNHG3 and the epithelial-mesenchymal transition (EMT) markers N-cadherin, Snail, vimentin and E-cadherin were detected using real-time quantitative PCR; the protein expressions of N-cadherin, Snail, vimentin and E-cadherin were determined using Western blotting. Cell counting kit-8 (CCK8) assay was utilized to assess the proliferation capacity of the transfected cells. Wound healing assay and Transwell assay were performed to evaluate the transversal and longitudinal migration and invasion abilities of the cells.

OBJECTIVE

SNHG3 was over-expressed in cervical cancer tissues and SiHa cells. In SiHa cells, knocking down SNHG3 significantly inhibited the proliferation (P < 0.001), migration (P < 0.01) and invasion abilities (P < 0.001) of the cells, down-regulated the expression levels of N-cadherin, Snail and vimentin (P < 0.001) and up-regulated the expression of E-cadherin (P < 0.001).

OBJECTIVE

SNHG3 may promote the proliferation, migration and invasion of SiHa cells by activating the EMT signaling pathway.

The Effect of lncRNA SNHG3 Overexpression on Lung Adenocarcinoma by Regulating the Expression of miR-890

The lncRNA small nucleolar host gene 3 (SNHG3) was discovered to play an important role in the occurrence and development of lung adenocarcinoma (LUAD). However, the underlying molecular mechanism of SNHG3 in LUAD remains unclear. In the present study, SNHG3 expression levels in LUAD tissues and cell lines were analyzed using reverse transcription-quantitative PCR. The effects of SNHG3 on the proliferation, apoptosis, migration, and invasion of LUAD cells were determined using Cell Counting Kit-8, colony formation, flow cytometry, wound healing, and Transwell chamber assays, respectively. The specific underlying mechanism of SNHG3 in LUAD was investigated using bioinformatics analysis and a dual luciferase reporter assay. The results revealed that SNHG3 expression levels were downregulated in LUAD tissues and cell lines. Functionally, SNHG3 overexpression suppressed the proliferation, migration, and invasion of LUAD cells, while promoting apoptosis. Mechanistically, microRNA- (miR-) 890 was identified as a potential target of SNHG3, and its expression was negatively regulated by SNHG3. Notably, SNHG3 was found to promote LUAD progression by targeting miR-890. In conclusion, the findings of the present study revealed that lncRNA SNHG3 promoted the occurrence and progression of LUAD by regulating miR-890 expression.

Zhike pingchuan granules improve bronchial asthma by regulating the IL-6/JAK2/STAT3 pathway

The present study aimed to investigate the effects of zhike pingchuan granules (ZKPC) on bronchial asthma and the underlying mechanism. A bronchial asthma mouse model was established by aerosol inhalation of ovalbumin. The changes in lung pathomorphology were observed by hematoxylin and eosin staining. The levels of IL-1β, TNF-α and IL-6 in bronchoalveolar lavage fluid (BALF) and serum were detected by corresponding ELISA kits. Levels of reactive oxygen species, malondialdehyde and superoxide dismutase in lung tissues were analyzed using corresponding kits. The expression of proteins related to apoptosis and the IL-6/janus kinase 2 (JAK2)/STAT3 pathway was detected by western blot analysis. The results showed that ZKPC significantly restored the dry/wet ratio and alleviated lung pathomorphology of bronchial asthmatic mice. In addition, ZKPC inhibits inflammation, oxidative stress levels and cell apoptosis in bronchial asthmatic mice and also suppressed the IL-6/JAK2/STAT3 pathway. Fedratinib (a JAK2 inhibitor) further strengthened the alleviative effects of ZKPC on bronchial asthma. In conclusion, ZKPC improved bronchial asthma by suppressing the IL-6/JAK2/STAT3 pathway.

The lncRNA OGFRP1/miR-149-5p/IL-6 axis regulates prostate cancer chemoresistance

BACKGROUND

The long non-coding RNA (lncRNA) OGFRP1 has been found to promote malignancy in prostate cancer (PC) and other cancer types. How this lncRNA functions in the regulation of PC chemoresistance, however, is poorly defined.

METHODS

qRT-PCR was employed to measure OGFRP1, miR-149-5p, and IL-6 expression in PC tissues and cells. IC50 values for paclitaxel and docetaxel in PC cells were assessed via a CCK-8 assay approach. Putative miR-149-5p binding targets were identified and validated through bioinformatics assays and luciferase reporter assays, respectively. The impact of OGFRP1 on PC chemoresistance in vivo was validated using a xenograft model system.

RESULTS

Docetaxel-resistant PC (PC/DR) cells and tissues exhibited reduced OGFRP1 expression and increased miR-149-5p expression. Knocking down OGFRP1 augmented the sensitivity of these PC cells to docetaxel and paclitaxel in vitro and in vivo. Mechanistically, OGFRP1 was found to bind and sequester miR-149-5p within PC/DR cells, thereby indirectly regulating IL-6 expression. Consistent with this model, the overexpression of IL-6 reversed the OGFRP1 knockdown-mediated reductions in docetaxel and paclitaxel IC50 values for these PC cells.

CONCLUSIONS

OGFRP1 can sequester miR-149-5p, thereby indirectly promoting IL-6 upregulation and thereby promoting chemoresistance in PC cells. This OGFRP1/miR-149-5p/IL-6 axis may thus be a promising target for therapeutic efforts aimed at PC chemosensitization and treatment.

Small nucleolar RNA host genes promoting epithelial-mesenchymal transition lead cancer progression and metastasis

The small nucleolar RNA host genes (SNHGs) belong to the long non-coding RNAs and are reported to be able to influence all three levels of cellular information-bearing molecules, that is, DNA, RNA, and proteins, resulting in the generation of complex phenomena. As the host genes of the small nucleolar RNAs (snoRNAs), they are commonly localized in the nucleolus, where they exert multiple regulatory functions orchestrating cellular homeostasis and differentiation as well as metastasis and chemoresistance. Indeed, worldwide literature has reported their involvement in the epithelial-mesenchymal transition (EMT) of different histotypes of cancer, being able to exploit peculiar features, for example, the possibility to act both in the nucleus and the cytoplasm. Moreover, SNHGs regulation is a fundamental topic to better understand their role in tumor progression albeit such mechanism is still debated. Here, we reviewed the biological functions of SNHGs in particular in the EMT process and discussed the perspectives for new cancer therapies.

KCNQ1OT1 lncRNA affects the proliferation, apoptosis, and chemoresistance of small cell lung cancer cells via the JAK2/STAT3 axis

Background

Small cell lung cancer (SCLC) is a devastating and aggressive neuroendocrine carcinoma characterized by high cellular proliferation and early metastatic spread. Numerous studies have demonstrated that long noncoding RNAs (lncRNAs) can regulate tumor generation and development, including in SCLC. The current study aimed to assess the effect of the lncRNA, KCNQ1OT1, on the proliferation, apoptosis, and chemoresistance of SCLC and the potential underlying molecular mechanism.

Methods

Matched chemo-resistant and sensitive cells were applied to RNA isolation and followed by expression profiling by microarray analysis and subsequent quantitative polymerase chain reaction (qPCR) validation. Cell viability and apoptosis were determined by Cell Counting Kit-8 and flow cytometry to examine the chemoresistance and apoptosis of KCNQ1OT1 knockdown with lentivirus-mediated RNA interference. Furthermore, cell proliferation was studied by colony formation, and invasion and migration were tested by Transwell cell invasion and wound-healing assays, respectively. A tumor xenograft model was established to determine the role of KCNQ1OT1 in tumor growth and chemoresistance in response to KCNQ1OT1 knockdown in vivo. Western blot analysis, qPCR, and immunohistochemistry were used to detect the levels of messenger RNA (mRNA) Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway-related markers.

Results

Higher expression of KCNQ1OT1 was detected in SCLC chemo-resistant verso chemo-sensitive cells. Knockdown of KCNQ1OT1 inhibited SCLC cell viability and cloning ability, hindered cell migration and invasion, induced apoptosis in vitro, and suppressed tumor growth and chemoresistance in vivo, by activating the JAK2/STAT3 signaling pathway.

Conclusions

This is the first study to indicate that lncRNA KCNQ1OT1 promotes cell proliferation and invasion, and prevents apoptosis of SCLC by activating the JAK2/STAT3 pathway.

m6A demethylase FTO induces NELL2 expression by inhibiting E2F1 m6A modification leading to metastasis of non-small cell lung cancer

Non-small cell lung cancer (NSCLC) represents one of the primary causes of cancer-related mortality all over the world. Following our initial finding of the upregulated expression of E2F transcription factor-1 (E2F1) in the NSCLC-related microarray, this study aimed to explore the regulatory role of E2F1 and underlying mechanism in NSCLC development. NSCLC cell viability, migration, and invasion were evaluated utilizing Cell Counting Kit 8 (CCK-8), 5-ethynyl-2′-deoxyuridine (EdU), wound-healing, and Transwell assays. Loss- and gain-function assays were performed to determine the effects of the fat mass and obesity-associated protein (FTO)/E2F1/neural epidermal growth factor-like 2 (NELL2) axis on NSCLC cell behaviors in vitro and NSCLC tumor growth in vivo. E2F1 was highly expressed in both NSCLC tissues and cells. E2F1 augmented the viability, migration, and invasion of NSCLC cells, which was attributable to E2F1 transcriptionally activating NELL2. FTO upregulated the expression of E2F1 by inhibiting the m6A modification of E2F1. The FTO/E2F1/NELL2 axis modulated NSCLC cell viability, migration, and invasion in vitro as well as affected NSCLC tumor growth and metastasis in vivo. The FTO/E2F1/NELL2 axis may impart pro-tumorigenic effects on the cell behavior of NSCLC cells and thus accelerate NSCLC progression.

Overexpression of lncRNA SNGH3 Predicts Unfavorable Prognosis and Clinical Outcomes in Human Cancers: Evidence from a Meta-Analysis

Long noncoding RNAs (lncRNAs) have been confirmed to play a crucial role in human disease, especially in tumor development and progression. Small nucleolar RNA host gene (SNHG3), a newly identified lncRNA, has been found dysregulated in various cancers. Nevertheless, the results remain controversial. Thus, we aim to analyze the comprehensive data to elaborate the association between SNHG3 expression and clinical outcomes in multiple cancers. We searched PubMed, Web of Science, Cochrane Library, Embase, and MEDLINE database to identify eligible articles. STATA software was applied to calculate the hazard ratio (HR) and odds ratio (OR) with 95% confidence interval (95% CI) for survival outcomes and clinical parameters, respectively. Besides, the data from The Cancer Genome Atlas (TCGA) dataset was extracted to verify the results in our meta-analysis. There were thirteen studies totaling 919 cancer patients involved in this meta-analysis. The results demonstrated that high SNHG3 expression was significantly associated with poor overall survival (OS) (HR = 2.53, 95% CI: 1.94-3.31) in cancers, disease-free survival (DFS) (HR = 3.89, 95% CI: 1.34-11.3), and recurrence-free survival (RFS) (HR = 2.42, 95% CI: 1.14-5.15) in hepatocellular carcinoma. Analysis stratified by analysis method, sample size, follow-up time, and cancer type further verified the prognostic value of SNHG3. Additionally, patients with high SNHG3 expression tended to have more advanced clinical stage, higher histological grade, earlier distant metastasis, and earlier lymph node metastasis. Excavation of TCGA dataset valuated that SNHG3 was upregulated in various cancers and predicted worse OS and DFS. Overexpressed SNHG3 was strongly associated with poor survival and clinical outcomes in human cancers and therefore can serve as a promising biomarker for predicting patients' prognosis.

Long Noncoding RNA Small Nucleolar Host Gene: A Potential Therapeutic Target in Urological Cancers

The incidence of urological cancer has been gradually increasing in the last few decades. However, current diagnostic tools and treatment strategies continue to have limitations. Substantial evidence shows that long noncoding RNAs (lncRNAs) play essential roles in carcinogenesis and the progression, treatment response and prognosis of multiple human cancers, including urological cancers, gastrointestinal tumours, reproductive cancers and respiratory neoplasms. LncRNA small nucleolar RNA host genes (SNHGs), a subgroup of lncRNAs, have been found to be dysregulated in tumour cell biology. In this review, we summarize the impacts of lncRNA SNHGs in urological malignancies and the underlying mechanisms.

lncRNA LINC00473 promotes proliferation, migration, invasion and inhibition of apoptosis of non-small cell lung cancer cells by acting as a sponge of miR-497-5p

Lung cancer is the leading cause of cancer-associated death worldwide and exhibits a poor prognosis. The present study aimed to determine the effect of long non-coding (lnc)RNA-LINC00473 on the development of non-small cell lung cancer (NSCLC) cells by regulating the expression of microRNA (miR)-497-5p. Reverse transcription-quantitative PCR was conducted to detect the level of LINC00473 and miR-497-5p. An MTT assay, flow cytometry and Transwell tests were performed to evaluate the proliferation, apoptosis, migration and invasion of NSCLC cells. Western blotting was performed to detect the expression of apoptosis- and migration-related proteins. RNA immunoprecipitation and a luciferase reporter assay were performed to verify the regulatory relationship between lncRNA-LINC00473 and miR-497-5p. LINC00473 expression was upregulated in lung cancer tissues and NSCLC cells (A549 and H1299) when compared with adjacent tissues or human bronchial epithelial cell lines and the 5-year survival rate was lower in patients with high LINC00473 expression compared with in patients with low LINC00473 expression. A negative correlation between LINC00473 and miR-497-5p was observed in lung cancer tissues. Proliferation, migration and invasion as well as the related protein levels were increased in A549 and H1299 transfected with pcDNA3.1-LINC00473, while the opposite results were obtained in A549 and H1299 transfected with small interfering (si)-LINC00473. Notably, it was demonstrated that LINC00473 could bind directly with miR-497-5p and inhibit its expression. miR-497-5p inhibitors reversed the effect of si-LINC00473. Furthermore, the present study demonstrated that LINC00473 promoted the malignant behaviour of NSCLC cells via regulating the ERK/p38 and MAPK signalling pathways and the expression of miR-497-5p.

Differentially expressed genes induced by β-caryophyllene in a rat model of cerebral ischemia-reperfusion injury

Experimental studies have shown that β-caryophyllene (BCP) improved neurological deficits of cerebral ischemia-reperfusion injury (CIRI) rats resulting from Middle Cerebral Artery Occlusion (MCAO). However, research on targets of BCP on CIRI has not been completed. In this study, the mRNA sequencing was used to distinguish various therapeutic multiple targets of BCP on CIRI. Differentially expressed genes (DEGs) were identified from RNA-seq analysis. CIRI induced up-regulated genes (CIRI vs. Sham) and BCP -induced down-regulated genes (BCP vs CIRI) were identified. Significant DEGs were identified only that expressed in each of all samples. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis of significant DEGs were determined by cluster Profiler. Protein interactive network (PPI) was analyzed using the String tool and Hub genes was identified by cytoHubba. Transcription factor (TF) regulatory network for the potential Hub genes was constructed. Western blot and ELISA were used to verified hub genes and relative inflammatory cytokines. After mRNA sequencing, a total of 411 DEGs were filtered based on the 2 series (CIRI vs. Sham and CIRI vs. BCP), with Pax1, Cxcl3 and Ccl20 are the most remarkable ones reversed by BCP. GO analysis was represented by DEGs involved in multiple biological process such as extra-cellular matrix organization, leukocyte migration, regulation of angiogenesis, reactive oxygen species metabolic process, etc. KEGG analysis showed that DEGs participated several signaling pathways including MAPK signaling pathway (rno04010), Cytokine-cytokine receptor interaction (rno04060), JAK-STAT signaling pathway (rno04630), and others. The protein-protein interaction (PPI) network consisted of 339 nodes and 1945 connections, and top ten Hub genes were identified by cytoHubba such as TIMP1, MMP-9, and STAT3. Subsequently, a TFs-miRNAs-targets regulatory network was established, involving 6 TFs, 5 miRNAs, and 10 hub genes, consisting of several regulated models such as Brd4 - rno-let-7e - Mmp9, Brd4 - rno-let-7i - Stat3, and Hnf4a- rno-let-7b -Timp1. Finally, western blot demonstrated that BCP could inhibit the increased TIMP1, MMP-9 and STAT3 expression in rat brains after I/R. ELISA represented that BCP could suppress inflammatory cytokines caused by CIRI and present anti-oxidative property. In conclusion, this study shows that the intervention of BCP can significantly reduce neurologic deficit, improve the cerebral ischemia, and a total of ten hub genes were found closely related to the treatment of BCP on CIRI. Prudent experimental validation suggests that the BCP might have the neuro-protective effects in CIRI by decreasing the expression of MMP-9 and TIMP-1, STAT3. In a sense, this study reveals that the MMP-9/TIMP-1 signaling pathway may be involved in the injury after CIRI and thus provides a new treatment strategy as well as a researching method for stroke.

ZNF674-AS1 antagonizes miR-423-3p to induce G0/G1 cell cycle arrest in non-small cell lung cancer cells

BACKGROUND

ZNF674-AS1, a recently characterized long noncoding RNA, shows prognostic significance in hepatocellular carcinoma and glioma. However, the expression and function of ZNF674-AS1 in non-small cell lung cancer (NSCLC) are unclear.

METHODS

In this work, we investigated the expression of ZNF674-AS1 in 83 pairs of NSCLC specimens and adjacent noncancerous lung tissues. The clinical significance of ZNF674-AS1 in NSCLC was analyzed. The role of ZNF674-AS1 in NSCLC growth and cell cycle progression was explored.

RESULTS

Our data show that ZNF674-AS1 expression is decreased in NSCLC compared to normal tissues. ZNF674-AS1 downregulation is significantly correlated with advanced TNM stage and decreased overall survival of NSCLC patients. Overexpression of ZNF674-AS1 inhibits NSCLC cell proliferation, colony formation, and tumorigenesis, which is accompanied by a G0/G1 cell cycle arrest. Conversely, knockdown of ZNF674-AS1 enhances the proliferation and colony formation of NSCLC cells. Biochemically, ZNF674-AS1 overexpression increases the expression of p21 through downregulation of miR-423-3p. Knockdown of p21 or overexpression of miR-423-3p blocks ZNF674-AS1-mediated growth suppression and G0/G1 cell cycle arrest. In addition, ZNF674-AS1 expression is negatively correlated with miR-423-3p in NSCLC specimens.

CONCLUSIONS

ZNF674-AS1 suppresses NSCLC growth by downregulating miR-423-3p and inducing p21. This work suggests the therapeutic potential of ZNF674-AS1 in the treatment of NSCLC.

Targeting SNHG3/miR-186-5p reverses the increased m6A level caused by platinum treatment through regulating METTL3 in esophageal cancer

Background

Platinum-based chemotherapy is a mainstay for treating esophageal cancer patients. In this manuscript, we have provided clues for influence of platinum on overall m6A level and further investigated the potential regulatory mechanism.

Methods

qRT-PCR was used to measure SNHG3 and miR-186-5p expression; ELISA and western blot were used to measure the expression of METTL3. CCK8 was used to measure the cell proliferation rate. Caspase 3/7 activity was used to measure the apoptosis rate. Dual luciferase reporter gene assay and RNA pull down assay were used to investigate the potential crosstalk between miR-186-5p and SNHG3; and miR-186-5p and METTL3.

Results

m6A level was increased when treated with platinum (CDDP, CPB and L-OHP). Besides, SNHG3 expression was induced and miR-186-5p expression was suppressed by platinum. Furthermore, SNHG3 could promote the m6A level, however miR-186-5p inhibited the m6A level through targeting METTL3. SNHG3 interacts with miR-186-5p to negatively regulate the expression of miR-186-5p; and miR-186-5p might bind to the 3′UTR of METTL3 to regulate its expression.

Conclusion

Platinum can increase the overall m6A level of esophageal cancer. SNHG3/miR-186-5p, induced by platinum, was involved in regulating m6A level by targeting METTL3. Our manuscript has provided clues that regulating m6A level might be a novel way to enhance the platinum efficacy.

MKL1-induced lncRNA SNHG18 drives the growth and metastasis of non-small cell lung cancer via the miR-211-5p/BRD4 axis

Megakaryocytic leukemia 1 (MKL1) is a key transcription factor involved in non-small cell lung cancer (NSCLC) growth and metastasis. Yet, its downstream target genes, especially long non-coding RNA (lncRNA) targets, are poorly investigated. In this study, we employed lncRNA array technology to identify differentially expressed lncRNAs in NSCLC cells with or without overexpression of MKL1. Candidate lncRNAs were further explored for their clinical significance and function in NSCLC. The results showed that MKL1 promoted the expression of lncRNA SNHG18 in NSCLC cells. SNHG18 upregulation in NSCLC specimens correlated with lymph node metastasis and reduced overall survival of NSCLC patients. SNHG18 expression served as an independent prognostic factor for NSCLC. Knockdown of SNHG18 blocked MKL1-induced growth and invasion of NSCLC cells in vitro. Animal studies validated the requirement for SNHG18 in NSCLC growth and metastasis. Moreover, overexpression of SNHG18 promoted NSCLC cell proliferation and invasion. Mechanically, SNHG18 exerted its prometastatic effects on NSCLC cells through repression of miR-211-5p and induction of BRD4. Clinical evidence indicated that SNHG18 expression was negatively correlated with miR-211-5p expression in NSCLC tissues. Altogether, SNHG18 acts as a lncRNA mediator of MKL1 in NSCLC. SNHG18 facilitates NSCLC growth and metastasis by modulating the miR-211-5p/BRD4 axis. Therefore, SNHG18 may be a potential therapeutic target for the treatment of NSCLC.

Dual relationship between long non-coding RNAs and STAT3 signaling in different cancers: New insight to proliferation and metastasis

Uncontrolled growth and metastasis of cancer cells is an increasing challenge for overcoming cancer, and improving survival of patients. Complicated signaling networks account for proliferation and invasion of cancer cells that need to be elucidated for providing effective cancer therapy, and minimizing their malignancy. Long non-coding RNAs (lncRNAs) are RNA molecules with a length of more than 200 nucleotides. They participate in cellular events, and their dysregulation in a common phenomenon in different cancers. Noteworthy, lncRNAs can regulate different molecular pathways, and signal transducer and activator of transcription 3 (STAT3) is one of them. STAT3 is a tumor-promoting factors in cancers due to its role in cancer proliferation (cell cycle progression and apoptosis inhibition) and metastasis (EMT induction). LncRNAs can function as upstream mediators of STAT3 pathway, reducing/enhancing its expression. This dual relationship is of importance in affecting proliferation and metastasis of cancer cells. The response of cancer cells to therapy such as chemotherapy and radiotherapy is regulated by lncRNA/STAT3 axis. Tumor-promoting lncRNAs including NEAT1, SNHG3 and H19 induces STAT3 expression, while tumor-suppressing lncRNAs such as MEG3, PTCSC3 and NKILA down-regulate STAT3 expression. Noteworthy, upstream mediators of STAT3 such as microRNAs can be regulated by lncRNAs. These complicated signaling networks are mechanistically described in the current review.