Effect and Mechanism of LncRNA HOTAIR on Migration, Apoptosis and Proliferation of Hepatocellular Carcinoma Cells

<sec> <title>Objective:</title> This study was designed to probe the influence and mechanism of lncRNA HOTAIR on migration, apoptosis and proliferation of hepatocellular carcinoma (HCC) cells. </sec> <sec> <title>Methods:</title> We evaluated LncRNA HOTAIR expression in HCC tissues and adjacent tissues, and serum of HCC patients and healthy controls. Later, we knocked down lncRNA HOTAIR, and utilized CCK-8 to determine Hep3B cell proliferation, flow cytometry for prospecting Hep3B cell apoptosis, and cell scratch assay for observing Hep3B cell migration.We anticipated the direct target of lncRNA HOTAIR, and adopted luciferase reporter assay to verify. Moreover, we inhibitedmiR-126-5p expression, and rescue experiment for evaluating the influence of si-HOTAIR+miR-126-5p inhibitors on Hep3B cell migration, apoptosis as well as proliferation. </sec> <sec> <title>Results:</title> Our results showed that lncRNA HOTAIR expression in tumor tissues and serum was significantly increased. Moreover, lncRNA HOTAIR inhibition significantly decreased the Hep3B cell proliferation rate, elevated Hep3B cell apoptosis rate, and inhibited Hep3B cell migration. Luciferase reporter assay suggested that miR-126-5p was the direct target of lncRNA HOTAIR. Furthermore, co-transfection of si-HOTAIR+miR-126-5p inhibitor could diminishthe effects of HOTAIR silencing on apoptosis, proliferation and migration. </sec> <sec> <title>Conclusion:</title> Silencing of lncRNA-HOTAIR can inhibit the HCC cell migration and proliferation, and increase the apoptosis by up-regulating miR-126-5p expression. </sec>

Mechanism of Long Noncoding RNA HOTAIR in Nucleus Pulposus Cell Autophagy and Apoptosis in Intervertebral Disc Degeneration

Objective. Intervertebral disc degeneration (IDD) contributes to cervical and lumbar diseases. Long noncoding RNAs (lncRNAs) are implicated in IDD. This study explored the mechanism of lncRNA HOTAIR in IDD. Methods. Normal and degenerative nucleus pulposus (NP) cells were isolated from NP tissues obtained in intervertebral disc surgery. Cell morphology was observed by immunocytochemistry staining and toluidine blue staining. NP cell markers were detected by RT-qPCR. Proliferation was detected by MTT assay. Autophagy-related proteins were detected by Western blot. Autophagosome was observed by monodansylcadaverine fluorescence staining. Apoptosis was detected by TUNEL staining and flow cytometry. si-HOTAIR and/or miR-148a inhibitor was introduced into degenerative NP cells. Binding relationships among HOTAIR, miR-148a, and PTEN were predicted and verified by dual-luciferase reporter assay and RNA pull-down. Finally, IDD rat models were established. Rat caudal intervertebral discs were assessed by HE staining. Expressions of HOTAIR, miR-148a, and PTEN were determined by RT-qPCR. Results. HOTAIR was highly expressed in degenerative NP cells p < 0.05 . si-HOTAIR inhibited degenerative NP cell apoptosis and autophagy p < 0.05 . HOTAIR upregulated PTEN as a sponge of miR-148a. miR-148a was poorly expressed in degenerative NP cells. miR-148a deficiency partially reversed the inhibition of si-HOTAIR on degenerative NP cell autophagy and apoptosis (all p < 0.05 ). In vivo assay confirmed that si-HOTAIR impeded autophagy and apoptosis in intervertebral disc tissues, thus improving pathological injury in IDD rats (all p < 0.05 ). Conclusion. LncRNA HOTAIR promoted NP cell autophagy and apoptosis via promoting PTEN expression as a ceRNA of miR-148a in IDD.

Expression of Long Noncoding RNA HOTAIR and Its Influence on the PTEN/PI3K/AKT Pathway and Inflammation in Patients With Osteoarthritis

Objective: Our research was designed to investigate the correlations among expression of PTEN/PI3K/AKT pathway, clinical-related indicators, and long noncoding RNA HOX transcript antisense RNA (lncRNA HOTAIR) in osteoarthritis (OA). Methods: The expression of immune-inflammatory indicators was detected in OA patients and normal people, and peripheral blood mononuclear cells (PBMCs) were extracted to induce human chondrocytes (CHs). Reverse transcription-quantitative polymerase chain reaction was performed to measure lncRNA HOTAIR expression. The levels of inflammatory cytokines and adiponectin were detected using enzyme-linked immunosorbent assay. Cell Counting Kit-8 was used to assess the viability of CHs. Western blot analysis was utilized to evaluate related protein expression.Results: LncRNA HOTAIR showed high expression in PBMCs of OA patients with the sensitivity and specificity of receiver-operating characteristics (ROC) curve according to the area under the ROC curve, indicating that lncRNA HOTAIR might act as a biomarker of OA. Moreover, lncRNA HOTAIR was positively correlated with total cholesterol, high sensitivity C-reactive protein, immunoglobulin G, tumor necrosis factor-α (TNF-α), and visual analog scale score, which were found to be independent risk factors for lncRNA HOTAIR expression. Besides, overexpression of lncRNA HOTAIR diminished cell viability and IL-10 expression but augmented TNF-α expression in OA-CHs stimulated by OA-PBMCs. Meanwhile, lncRNA HOTAIR overexpression elevated the levels of PI3K, AKT proteins and reduced PTEN protein expression in OA-CHs.Conclusions: Conclusively, lncRNA HOTAIR was upregulated in PBMCs of OA patients, which facilitated the inflammatory response of OA by orchestrating inflammatory cytokines and the PTEN/PI3K/AKT pathway.

Phenotypic Changes of LncRNA Hotair in Non-Small-Cell Lung Cancer and Its Clinical Application

Non-small-cell lung cancer (NSCLC) is one of the main causes of death of malignant tumors of the respiratory system. At present, the clinical demand for biomarkers for predicting and diagnosing the disease is increasing. Overexpression of LncRNA Hotair (Homeobox transcriptional antisense intergenic RNA) has been previously reported to be associated with poor prognosis and high mortality in different malignancies. qRT-PCR results showed that the expression of LncRNA Hotair in tumor tissue and serum of patients with non-small-cell lung cancer was significantly upregulated. Clinicopathological correlation analysis showed that the upregulation of LncRNA Hotair expression was closely related to lymph node metastasis and tumor lymph node metastasis (TNM) stage ( P < 0.05). The results showed that transfection of pcDNA3.1-Hotair could promote the expression of LncRNA Hotair in NSCLC, while transfection of Si-Hotair could reduce the expression level of LncRNA Hotair, hinder the migration and invasion of cancer cells, and promote cell apoptosis. After transfection of Si-Hotair, molecular markers related to migration, the level of E-cadherin and Bax, increased and the level of vimentin, Bcl-2, MMP-3, VEGF, Ki-67 and PCNA decreased. This shows that the proliferation and migration of A549 cells are promoted and LncRNA Hotair deletion can inhibit the proliferation and migration of lung cancer cells. These results show that the expression level of LncRNA Hotair of NSCLC cell lines can promote the invasion and migration of NSCLC, and its expression has a significant correlation with Lymph node metastasis, tumor size, and TNM stage. Therefore, this target is of great significance for the clinical diagnosis and treatment of NSCLC.

Orthogonal Proteomics Methods to Unravel the HOTAIR Interactome

Accumulating evidence highlights the role of long non-coding RNAs (lncRNA) in cellular homeostasis, and their dysregulation in disease settings. Most lncRNAs function by interacting with proteins or protein complexes. While several orthogonal methods have been developed to identify these proteins, each method has its inherent strengths and limitations. Here, we combine two RNA-centric methods ChIRP-MS and RNA-BioID to obtain a comprehensive list of proteins that interact with the well-known lncRNA HOTAIR. Overexpression of HOTAIR has been associated with a metastasis-promoting phenotype in various cancers. Although HOTAIR is known to bind with PRC2 and LSD1 protein complexes, only very limited unbiased comprehensive approaches to map its interactome have been performed. Both ChIRP-MS and RNA-BioID data sets show an association of HOTAIR with mitoribosomes, suggesting that HOTAIR has functions independent of its (post-)transcriptional mode-of-action.

STEM-23. LncRNA HOTAIR SPONGES miR301a-3p TO PROMOTE GLIOMA’S PROLIFERATION AND INVASION THROUGH THE ACTIVATION OF FosL1

BACKGROUND Non-coding RNAs, including LncRNAs, function in regulating glioblastomas’ numerous oncogenic phenotypes, such as invasiveness and stemness of glioblastoma stem cells. These LncRNAs contain long non-encoding RNA transcripts &gt;200 nucleotides in length, many of which show cell type-specific expression. In this project, we investigated how TRPM7, a promoter for glioma’s proliferation and invasion, regulates LncRNA and contributes to glioma tumorigenesis. METHODS 1) Total RNA, from either with A172 glioma cells or A172 glioma cells with TRPM7 knocked out (A172 KO), were extracted and then parallelly subjected to Human Cancer Pathway Finder, RT2 LncRNA PCR Array. 2) We then analyzed the prognostic role of LncRNAs using a publicly available bioinformatics data set (www.Oncolanc.org). 3) We examined the effects of TRPM7-regulated LncRNA, and its downstream molecules miR301a-3p and FosL1 oncogene, on the proliferation and invasion of glioma cells in A172 and PDX-L12 cells by either inhibition or activation of the above molecules. RESULTS 1) Data analysis from RT2 data resulted in a list of 10 downregulated and 7 upregulated LncRNAs whose transcripts are statistically significant with fold changes greater than 2.0 by TRPM7 knockout. 2) The results showed that TRPM7 functions as a positive regulator of LncRNA, HOTAIR, which is an unfavorable prognostic factor of 7-year overall survival in glioma patients. 3) In addition, we found that LncRNA HOTAIR sponges miR-301a-3p to promote proliferation, invasion, and stemness of glioma through upregulating the oncogene FosL1. 4) Furthermore, we identified that FosL1 is a novel prognostic marker of glioma patients. CONCLUSION Our results demonstrated the role of TRPM7-regulated LncRNA HOTAIR as a miRNA sponge in glioma, which shed new light on LncRNA-directed therapeutics in glioma.