LncRNA H19 promotes lung cancer proliferation and metastasis by inhibiting miR-200a function

Low expression of long non-coding RNA ARAP1-AS1 can inhibit lung cancer proliferation by inducing G0/G1 cell cycle organization

Background

This paper examines the expression, function, and molecular mechanism of long non-coding ribonucleic acid (lncRNA) ARAP1 antisense RNA 1 (ARAP1-AS1) in lung cancer. Specifically, it aims to clarify the molecular mechanism of lncRNA ARAP1-AS1 that affects the occurrence and development of lung cancer, and provide a theoretical basis and molecular targets for targeted therapy or early diagnosis of lung cancer.

Methods

Fluorescence quantitative detection of lncRNA ARAP1-AS1 expression in lung cancer tissues and cell lines, and methylthiazolyldiphenyl-tetrazolium (MTT), plate cloning experiment, and flow cytometry were used to detect the effect of knockdown of lncRNA ARAP1-AS1 on cell proliferation, clone formation, and the cell cycle, respectively. Western blotting was used to detect the expression of cell cycle-related proteins as well as the effect of knockdown of lncRNA ARAP1-AS1 on lung cancer. Cell proliferation was assessed by a nude mouse subcutaneous tumor formation experiment.

Results

LncRNA ARAP1-AS1 is highly expressed in lung cancer tissues and cells. Knockdown of LncRNA ARAP1-AS1 can significantly inhibit the proliferation and clonal formation of lung cancer cells and induce G0/G1 cell cycle arrest. Knockdown of ARAP1-AS1 can markedly inhibit the expression of cell cycle-related protein cyclin D1, but has no significant effect on the expression of cyclin-dependent kinase (CDK)4 and CDK6. Furthermore, knockdown of ARAP1-AS1 can also notably inhibit the growth of lung cancer cells and substantially reduce the expression of Ki-67 in tumor-bearing tissues in nude mice.

Conclusions

LncRNA ARAP1-AS1 is highly expressed in lung cancer. Knocking down of this gene can significantly inhibit cell proliferation in vitro and in vivo, and can also cause G0/G1 cell cycle arrest by inhibiting the expression of cyclin D1.

Long intergenic non-coding RNA Linc00485 promotes lung cancer progression by modulating miR-298/c-Myc axis

Long non‐coding RNAs (lncRNAs), which are non‐protein‐coding transcripts, are emerging as novel biomarkers for cancer diagnosis. Their dysregulation is increasingly recognized to contribute to the development and progression of human cancers, including lung cancer. Linc00485 is a newly discovered cancer‐related lncRNA; however, little is known about its role in lung cancer progression. In this study, we found that the expression of Linc00485 was significantly increased in human lung cancer tissue and associated with malignant phenotypes, including tumour‐node‐metastasis (TNM) stage, metastasis and relapse. Furthermore, the proliferative, migratory and invasive abilities of lung cancer cells in vitro were significantly enhanced by overexpression of Linc00485 but inhibited by its silencing. Mechanistically, Linc00485 regulated the expression of c‐Myc by directly binding to miR‐298; the effects of Linc00485 overexpression could be significantly reversed by a c‐Myc inhibitor or small interfering RNA. Xenotransplantation experiments showed that Linc00485 silencing significantly weakened the proliferation potential of A549 cells in vivo. Overall, these findings indicate that Linc00485 overexpression down‐regulates miR‐298, resulting in the up‐regulation of c‐Myc and thereby promoting the development of lung cancer.

Long non-coding RNA H19 deficiency ameliorates bleomycin-induced pulmonary inflammation and fibrosis

Background

The poor understanding of pathogenesis in idiopathic pulmonary fibrosis (IPF) impaired development of effective therapeutic strategies. The aim of the current study is to investigate the roles of long non-coding RNA H19 (lncRNA H19) in the pulmonary inflammation and fibrosis of IPF.

Methods

Bleomycin was used to induce pulmonary inflammation and fibrosis in mice. The mRNAs and proteins expression in lung tissues was determined by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. H19 knockout (H19^−/−) mice were generated by CRISPR/Cas9.

Results

The expression of H19 mRNA was up-regulated in fibrotic lungs patients with IPF as well as in lungs tissues that obtained from bleomycin-treated mice. H19^−/− mice suppressed bleomycin-mediated pulmonary inflammation and inhibited the Il6/Stat3 signaling. H19 deficiency ameliorated bleomycin-induced pulmonary fibrosis and repressed the activation of TGF-β/Smad and S1pr2/Sphk2 in the lungs of bleomycin-treated mice.

Conclusions

Our data suggests that H19 is a profibrotic lncRNA and a potential therapeutic target for IPF.

LncRNA GATA6-AS1 Inhibits the Progression of Non-Small Cell Lung Cancer via Repressing microRNA-543 to Up-Regulating RKIP

Background

Much evidence unveils the significance of long non-coding RNAs (lncRNAs) in diverse cancers. This study was designed to clarify the function and mechanism of lncRNA GATA6 antisense RNA 1 (GATA6-AS1) in the progression of non-small cell lung cancer (NSCLC).

Methods

GATA6-AS1, miR-543 and Raf kinase inhibitor protein (RKIP) mRNA expressions were detected by qRT-PCR. Chi-square test was adopted to analyze the relationship between GATA6-AS1 expression and the clinicopathological parameters of NSCLC patients. NSCLC cells H1299 and H460 cells were used as overexpression or knockdown models, respectively, and cell proliferation and metastasis were determined by CCK-8 and Transwell assays. RKIP, E-cadherin, N-cadherin, STAT3, p-STAT3 expressions in NSCLC cells were detected by Western blot. The targeting relationship between GATA6-AS1 and miR-543 was confirmed by dual-luciferase reporter assay.

Results

GATA6-AS1 was significantly lowly expressed in NSCLC tissues and cell lines, and its low expression level was significantly correlated with larger tumor size and positive lymph node metastasis. GATA6-AS1 overexpression inhibited the proliferation, migration, invasion and epithelial–mesenchymal transition of NSCLC cells, while GATA6-AS1 knockdown caused the opposite effects. Mechanistically, it was confirmed that GATA6-AS1 impeded NSCLC cell proliferation and metastasis by adsorbing miR-543 and up-regulating the expression of RKIP.

Conclusions

As a tumor suppressor, GATA6-AS1 participates in suppressing the progression of NSCLC by modulating the miR-543/RKIP axis.

Levonorgestrel Ameliorates Adenomyosis via lncRNA H19/miR-17/TLR4 Pathway

Purpose

To explore the mechanism of levonorgestrel (LNG)-ameliorating adenomyosis through long non-coding RNA H19 (lncRNA H19)/miR-17/Toll-like receptor 4 (TLR4) pathway.

Patients and Methods

A total of 71 cases of adenomyosis and 54 cases of normal endometrium were sampled. Quantitative polymerase chain reaction (qPCR) was employed to quantify lncRNA H19, miR-17, and TLR4 mRNA, while Western blot (WB) was used to quantify TLR4 protein. Effects of LNG on normal endometrial stromal cells (ESCs) were evaluated. Suppression/over-expression vectors of lncRNA H19, miR-17, and TLR4 were constructed to observe their effects on ESCs.

Results

MiR-17 and TLR4 mRNA were up-regulated and lncRNA H19 was down-regulated in adenomyosis. After LNG treatment, lncRNA H19 was up-regulated while miR-17 and TLR4 were down-regulated. LNG, up-regulation of lncRNA H19, and down-regulation of miR-17 and TLR4 portend increased apoptosis, G1-arrested cells, as well as inhibited inflammation. Dual-luciferase reporter (DLR) assay conformed the targeting relation of lncRNA H19/miR-17/TLR4 pathway.

Conclusion

LNG ameliorates adenomyosis via lncRNA H19/miR-17/TLR4 pathway.

Role of microRNA/Epithelial-to-Mesenchymal Transition Axis in the Metastasis of Bladder Cancer

Bladder cancer (BC) is the 11th most common diagnosed cancer, and a number of factors including environmental and genetic ones participate in BC development. Metastasis of BC cells into neighboring and distant tissues significantly reduces overall survival of patients with this life-threatening disorder. Recently, studies have focused on revealing molecular pathways involved in metastasis of BC cells, and in this review, we focus on microRNAs (miRNAs) and their regulatory effect on epithelial-to-mesenchymal transition (EMT) mechanisms that can regulate metastasis. EMT is a vital process for migration of BC cells, and inhibition of this mechanism restricts invasion of BC cells. MiRNAs are endogenous non-coding RNAs with 19-24 nucleotides capable of regulating different cellular events, and EMT is one of them. In BC cells, miRNAs are able to both induce and/or inhibit EMT. For regulation of EMT, miRNAs affect different molecular pathways such as transforming growth factor-beta (TGF-β), Snail, Slug, ZEB1/2, CD44, NSBP1, which are, discussed in detail this review. Besides, miRNA/EMT axis can also be regulated by upstream mediators such as lncRNAs, circRNAs and targeted by diverse anti-tumor agents. These topics are also discussed here to reveal diverse molecular pathways involved in migration of BC cells and strategies to target them to develop effective therapeutics.

Enhancement of Breast Cancer Cell Aggressiveness by lncRNA H19 and its Mir-675 Derivative: Insight into Shared and Different Actions

Breast cancer is a major public health problem and the leading world cause of women death by cancer. Both the recurrence and mortality of breast cancer are mainly caused by the formation of metastasis. The long non-coding RNA H19, the precursor of miR-675, is involved in breast cancer development. The aim of this work was to determine the implication but, also, the relative contribution of H19 and miR-675 to the enhancement of breast cancer metastatic potential. We showed that both H19 and miR-675 increase the invasive capacities of breast cancer cells in xenografted transgenic zebrafish models. In vitro, H19 and miR-675 enhance the cell migration and invasion, as well as colony formation. H19 seems to induce the epithelial-to-mesenchymal transition (EMT), with a decreased expression of epithelial markers and an increased expression of mesenchymal markers. Interestingly, miR-675 simultaneously increases the expression of both epithelial and mesenchymal markers, suggesting the induction of a hybrid phenotype or mesenchymal-to-epithelial transition (MET). Finally, we demonstrated for the first time that miR-675, like its precursor H19, increases the stemness properties of breast cancer cells. Altogether, our data suggest that H19 and miR-675 could enhance the aggressiveness of breast cancer cells through both common and different mechanisms.

LncRNA MEG3 inhibits non-small cell lung cancer via interaction with DKC1 protein

Long non-coding RNA (lncRNA) MEG3 is a key biomarker and therapeutic target in lung cancer; however, its underlying molecular mechanism in lung cancer progression remains unclear. The present study demonstrated a novel regulatory axis in lung cancer, lncRNA MEG3/dyskeratosis congenita 1 (DKC1), and further investigated the effects and molecular mechanism of lncRNA MEG3/DKC1 in lung cancer. RT-qPCR and western blot analysis were performed to determine gene and protein expression levels. The RNA immunoprecipitation assay was performed to verify binding between lncRNA MEG3 and DKC1. Flow cytometry analysis was performed to assess cell apoptosis, while the Cell Counting Kit-8 assay was performed to determine cell viability. Transwell and wound healing assays were performed to assess cell invasion and migration, respectively. Telomerase activity was measured using the quantitative TeloTAGGG Telomerase PCR-ELISA kit. The results demonstrated that lncRNA MEG3 was downregulated, while its binding protein, DKC1, was upregulated in lung cancer cells. Furthermore, lncRNA MEG3 inhibited cell proliferation, migration, invasion and telomerase activity in A549 cells by downregulating DKC1. lncRNA MEG3 inhibited non-small cell lung cancer progression by inhibiting telomere function, cell proliferation, telomerase activity, cell migration and invasion via regulation of the DKC1 protein expression. LncRNA MEG3/DKC1 was identified as a novel dual-directional regulatory axis in the present study, acting as a promising target for the treatment of lung cancer.

New twists on long noncoding RNAs: from mobile elements to motile cancer cells

The purpose of this review is to highlight several areas of lncRNA biology and cancer that we hope will provide some new insights for future research. These include the relationship of lncRNAs and the epithelial to mesenchymal transition (EMT) with a focus on transcriptional and alternative splicing mechanisms and mRNA stability through miRNAs. In addition, we highlight the potential role of enhancer e-lncRNAs, the importance of transposable elements in lncRNA biology, and finally the emerging area of using antisense oligonucleotides (ASOs) and small molecules to target lncRNAs and their therapeutic implications.

Exosomal Long Non-Coding RNAs in Lung Diseases

Within the non-coding genome landscape, long non-coding RNAs (lncRNAs) and their secretion within exosomes are a window that could further explain the regulation, the sustaining, and the spread of lung diseases. We present here a compilation of the current knowledge on lncRNAs commonly found in Chronic Obstructive Pulmonary Disease (COPD), asthma, Idiopathic Pulmonary Fibrosis (IPF), or lung cancers. We built interaction networks describing the mechanisms of action for COPD, asthma, and IPF, as well as private networks for H19, MALAT1, MEG3, FENDRR, CDKN2B-AS1, TUG1, HOTAIR, and GAS5 lncRNAs in lung cancers. We identified five signaling pathways targeted by these eight lncRNAs over the lung diseases mentioned above. These lncRNAs were involved in ten treatment resistances in lung cancers, with HOTAIR being itself described in seven resistances. Besides, five of them were previously described as promising biomarkers for the diagnosis and prognosis of asthma, COPD, and lung cancers. Additionally, we describe the exosomal-based studies on H19, MALAT1, HOTAIR, GAS5, UCA1, lnc-MMP2-2, GAPLINC, TBILA, AGAP2-AS1, and SOX2-OT. This review concludes on the need for additional studies describing the lncRNA mechanisms of action and confirming their potential as biomarkers, as well as their involvement in resistance to treatment, especially in non-cancerous lung diseases.

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

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

Long Non-Coding RNA in the Pathogenesis of Cancers

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