LncRNA SNHG12 promotes proliferation and epithelial mesenchymal transition in hepatocellular carcinoma through targeting HEG1 via miR-516a-5p

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.

The pivotal role of EMT-related noncoding RNAs regulatory axes in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) remains a major health problem worldwide, being the leading cause of cancer-related deaths, with limited treatment options, especially in its advanced stages. Tumor resistance is closely associated with the activation of the EMT phenomenon and its reversal, being modulated by different molecules, including noncoding RNAs (ncRNAs). Noncoding RNAs have the potential to function as both tumor suppressors and oncogenic molecules, controlling the malignant potential of HCC cells. Basically, these molecules circulate in the tumor microenvironment, encapsulated in exosomes. Their impact on cell biology is more significant than originally expected, which makes related research rather complex. The temporal and spatial expression patterns, precise roles and mechanisms of specific ncRNAs encapsulated in exosomes remain primarily unknown in different stages of the disease. This review aims to highlight the recent advances in ncRNAs related to EMT and classifies the described mechanism as direct and indirect, for a better summarization. Moreover, we provide an overview of current research on the role of ncRNAs in several drug resistance-related pathways, including the emergence of resistance to sorafenib, doxorubicin, cisplatin and paclitaxel therapy. Nevertheless, we comprehensively discuss the underlying regulatory mechanisms of exosomal ncRNAs in EMT-HCC via intercellular communication pathways.

Long non-coding RNAs (lncRNAs) in hepatocellular carcinoma progression: Biological functions and new therapeutic targets

Liver is an important organ in body that performs vital functions such as detoxification. Liver is susceptible to development of cancers, and hepatocellular carcinoma (HCC) is among them. 75-85% of liver cancer cases are related to HCC. Therefore, much attention has been directed towards understanding factors mediating HCC progression. LncRNAs are epigenetic factors with more than 200 nucleotides in length located in both nucleus and cytoplasm and they are promising candidates in cancer therapy. Directing studies towards understanding function of lncRNAs in HCC is of importance. LncRNAs regulate cell cycle progression and growth of HCC cells, and they can also induce/inhibit apoptosis in tumor cells. LncRNAs affect invasion and metastasis in HCC mainly by epithelial-mesenchymal transition (EMT) mechanism. Revealing the association between lncRNAs and downstream signaling pathways in HCC is discussed in the current manuscript. Infectious diseases can affect lncRNA expression in mediating HCC development and then, altered expression level of lncRNA is associated with drug resistance and radio-resistance. Biomarker application of lncRNAs and their role in prognosis and diagnosis of HCC are also discussed to pave the way for treatment of HCC patients.

The hsa-miR-516a-5p and hsa-miR-516b-5p microRNAs reduce the migration and invasion on T98G glioblastoma cell line

microRNAs (miRNAs) are involved in numerous functions and processes in the brain and other organs through the regulation of gene and protein expression. miRNA dysregulation is associated with the development of several diseases, including the brain and Central Nervous System cancer (CNS). The hsa-miR-516a-5p and hsa-miR-516b-5p are involved in proliferation, migration, and invasion in different tumor models, but their antitumor effect has not been evaluated in cancer of CNS. Therefore, we aimed to assess the effect of the miRNAs hsa-miR-516a-5p and miRNA hsa-miR-516b-5p on the Glioblastoma cell line (T98G). We used synthetic miRNA mimics to induce the overexpression of both miRNAs in the cell line, which was corroborated by RT-qPCR. Next, we evaluated the effect on proliferation, migration, and invasion using the CyQuant direct kit, ThinCert ™ inserts and invasion BioCoat ™ Matrigel® Invasion Chambers. We found upregulation of these miRNAs induced significant changes on the migration and invasion processes of T98G cells, but not affected the proliferation rate. These results suggest that both microRNAs could be playing an important role in the control of tumor progression towards metastasis. The bioinformatics analysis showed that target genes for these miRNAs are involved in different biological processes such as in cell adhesion molecule binding and cell junction disassembly, which are important for cancer progression. Further studies and experimental validation are needed to identify the genes regulated by microRNAs.

Revealing lncRNA Biomarkers Related to Chronic Obstructive Pulmonary Disease Based on Bioinformatics

Background

Chronic obstructive pulmonary disease (COPD) is a common chronic disease of the respiratory tract, with high prevalence, high disability, and poor prognosis. However, the molecular mechanism of COPD needs to be further revealed.

Methods

We obtained the gene expression profile and miRNA expression profile of COPD patients from Gene Expression Omnibus (GEO) database, and the differentially expressed genes (DEGs) and differentially expressed miRNAs (DEmis) in COPD were identified. Subsequently, the COPD-related ceRNA network was constructed based on the interaction between lncRNA, miRNA, and mRNA using the lncACTdb database. Finally, the Cytoscape software was used to analyze the network topology and COPD-related lncRNAs.

Results

Firstly, the 519 DEGs and 17 DEmis were identified from COPD GEO datasets. GO enrichment showed that leukocyte chemotaxis, cell chemotaxis, and myeloid leukocyte migration were upregulated, and muscle and membrane repolarization-related biological progress were downregulated in COPD. KEGG pathway enrichment shows that the p53 pathway was upregulated in COPD. Hallmark enrichment showed that chronic neutrophil inflammation was a sign of the pathogenesis of COPD. Next, a ceRNA network including 93 DEGs, 2 DEmi, 463 lncRNAs, and 1157 DEG-lncRNA, DEmi-lncRNA, and DEmi-DEG interactions were obtained. The hub-lncRNA (the network is ranked in the top 10) as the core marker of COPD, including SNHG12, SLFNL1-AS1, KCNQ1OT1, XIST, EAF1-AS1, FOXD2-AS1, NORAD, PINK1-AS and RP11-69E11.4. And the cytoHubba analysis identified ATM, SMAD7 and HIF1A as hub genes of ceRNA network.

Conclusion

This study provides a landscape of ceRNA network of COPD, which help to reveal the underlying pathophysiological mechanisms of COPD and shed light on novel therapeutic strategies for COPD.

Circ_0005397 enhances hepatocellular carcinoma progression through miR-1283/HEG1

INTRODUCTION AND OBJECTIVES

Circular RNA (circRNA) has been confirmed to be an important regulator for the progression of hepatocellular carcinoma (HCC). However, the role and regulatory mechanism of circ_0005397 in HCC are not completely clear.

PATIENTS AND METHODS

Fifty HCC patients were included in this study. Reverse transcription-qPCR analysis was used to appraise circ_0005397, microRNA (miR)-1283, HEG homolog 1 (HEG1) mRNA expression levels, while western blot was used to identify HEG1, PCNA, Bax and Bcl-2 protein expression levels. Furthermore, cell proliferation, apoptosis, migration, invasion and angiogenesis were judged through cell counting kit-8 assay, EdU assay, Caspase3 activity test, flow cytometry, transwell assay and tube formation experiment. Dual-luciferase reporter assay and RIP assay were used to verify the targeting relationship between miR-1283 and circ_0005397 or HEG1. Finally, the effect of circ_0005397 on HCC tumor development was detected by mice experiments in vivo.

RESULTS

Circ_0005397 was highly expressed in HCC tissues and cells, in HCC cell lines. Circ_0005397 silencing inhibited proliferation, migration, invasion and angiogenesis, while induced apoptosis in HCC cells. Circ_0005397 could sponge miR-1283, and miR-1283 could target HEG1. MiR-1283 inhibitor incompletely counteracted the effect of si-circ_0005397 on HCC cell progression, while HEG1 overexpression partially overturned the effect of miR-1283 on HCC cell progression. Circ_0005397 regulated the expression of HEG1 through targeting miR-1283. Moreover, circ_0005397 silencing blocked the growth of HCC tumors in vivo.

CONCLUSIONS

Circ_0005397 regulated HEG1 by targeting miR-1283, thereby promoting HCC development.

KMT2B promotes the growth of renal cell carcinoma via upregulation of SNHG12 expression and promotion of CEP55 transcription

Background

This study aims to clarify the mechanistic action of long non-coding RNA (lncRNA) SNHG12 in the development of renal cell carcinoma (RCC), which may be associated with promoter methylation modification by KMT2B and the regulation of the E2F1/CEP55 axis.

Methods

TCGA and GEO databases were used to predict the involvement of SNHG12 in RCC. Knockdown of SNHG12/E2F1/CEP55 was performed. Next, SNHG12 expression and other mRNAs were quantified by RT-qPCR. Subsequently, CCK-8 was used to detect cell proliferation. Wound healing assay and Transwell assay were used to detect cell migration and invasion, respectively. The in vitro angiogenesis of human umbilical vein endothelial cells (HUVECs) was explored by matrigel-based capillary-like tube formation assay. ChIP assay was used to detect H3K4me3 in SNHG12 promoter region. The binding of E2F1 to CEP55 promoter region was analyzed with ChIP and dual luciferase reporter assays. RIP assay was used to detect the binding of SNHG12 to E2F1. Finally, the effect of SNHG12 on the tumor formation and angiogenesis of RCC was assessed in nude mouse xenograft model.

Results

SNHG12 was highly expressed in RCC tissues and cells, and it was related to the poor prognosis of RCC patients. SNHG12 knockdown significantly inhibited RCC cell proliferation, migration, and invasion and HUVEC angiogenesis. KMT2B up-regulated SNHG12 expression through modifying H3K4me3 in its promoter region. In addition, SNHG12 promoted CEP55 expression by recruiting the transcription factor E2F1. Knockdown of SNHG12 blocked E2F1 recruitment and down-regulated the expression of CEP55, thereby inhibiting tumor formation and angiogenesis in nude mice.

Conclusion

The evidence provided by our study highlighted the involvement of KMT2B in up-regulation of lncRNA as well as the transcription of CEP55, resulting in the promotion of angiogenesis and growth of RCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02607-w.

Long noncoding RNASEH1-AS1 exacerbates the progression of non-small cell lung cancer by acting as a ceRNA to regulate microRNA-516a-5p/FOXK1 and thereby activating the Wnt/β-catenin signaling pathway

BACKGROUND

Till now, no study has focused on the functions of RNASEH1 antisense RNA 1 (RNASEH1-AS1) in non-small cell lung cancer (NSCLC). Accordingly, we measured the expression of RNASEH1-AS1 in NSCLC and characterized its functions in detail. Finally, our research elucidated the mechanisms that occurred downstream of RNASEH1-AS1.

METHODS

RNASEH1-AS1 expression was examined utilizing TCGA database and qRT-PCR. Functional experiments were conducted to study the tumor-associated functions of RNASEH1-AS1. The targeting relationship among RNASEH1-AS1, microRNA-516a-5p (miR-516a-5p), and forkhead box K1 (FOXK1) was revealed utilizing RNA immunoprecipitation and luciferase reporter assays.

RESULTS

Utilizing TCGA database and our own cohort, we found a significantly increased level of RNASEH1-AS1 in NSCLC. The high level of RNASEH1-AS1 was markedly related with poor clinical outcomes. Knockdown of RNASEH1-AS1 expression inhibited NSCLC cell growth, metastatic capacities, and epithelial-mesenchymal transition and promoted the apoptosis in vitro, whereas RNASEH1-AS1 overexpression exerted the opposite effects. Additionally, knocking down RNASEH1-AS1 expression suppressed tumor growth in vivo. RNASEH1-AS1 was confirmed to act as a miR-516a-5p sponge, consequently upregulating FOXK1 expression in NSCLC cells. As revealed by the subsequent rescue experiments, the miR-516a-5p/FOXK1 axis served as a downstream effector of RNASEH1-AS1. In addition, by controlling the miR-516a-5p/FOXK1 axis, RNASEH1-AS1 was capable of activating the Wnt/β-catenin pathway.

CONCLUSION

RNASEH1-AS1 exacerbated the oncogenicity of NSCLC by affecting the miR-516a-5p/FOXK1 axis and consequently promoting the activation of Wnt/β-catenin pathway. Our newly identified RNASEH1-AS1/miR-516a-5p/FOXK1/Wnt/β-catenin network may offer an interesting foundation for NSCLC treatment in the clinic.

Detection and analysis of long noncoding RNA expression profiles related to epithelial-mesenchymal transition in keloids

BACKGROUND

The role of epithelial-mesenchymal transition (EMT) in the pathogenesis of keloids is currently raising increasing attention. Long noncoding RNAs (lncRNAs) govern a variety of biological processes, such as EMT, and their dysregulation is involved in many diseases including keloid disease. The aim of this study was to identify differentially expressed EMT-related lncRNAs in keloid tissues versus normal tissues and to interpret their functions.

RESULTS

Eleven lncRNAs and 16 mRNAs associated with EMT were identified to have differential expression between keloid and normal skin tissues (fold change > 1.5, P < 0.05). Gene Ontology (GO) analysis showed that these differentially expressed mRNAs functioned in the extracellular matrix, protein binding, the positive regulation of cellular processes, the Set1C/COMPASS complex and histone acetyltransferase activity. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis demonstrated that these mRNAs are involved in pathways in cancer. The lncRNA, XLOC_000587 may promote cell proliferation and migration by enhancing the expression of ENAH, while AF268386 may facilitate the invasive growth of keloids by upregulating DDR2.

CONCLUSIONS

We characterized the differential expression profiles of EMT-related lncRNAs and mRNAs in keloids, which may contribute to preventing the occurrence and development of keloids by targeting the corresponding signaling pathways. These lncRNAs and mRNAs may provide biomarkers for keloid diagnosis and serve as potential targets for the treatment of this disease.

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.