HOTAIR Levels Research Articles

P.038 Investigating the role of long non-coding RNAs in glioblastoma multiforme

Background: Malignant gliomas are the most common and deadly brain tumors. Mean survival rate for a patient diagnosed with a glioblastoma multiforme (GBM) remains slightly over one year. Standard of care consists of treatment with temozolomide (TMZ) and radiotherapy. Recent work has highlighted functions of long non-coding RNAs (lncRNAs) in GBM progression and TMZ response even though the information regarding these newly discovered molecules is sparse. The overarching objective of this project was thus to assess the expression of select lncRNAs in GBM tumor samples and in models of TMZ resistance. Methods: A qRT-PCR-based approach was undertaken to measure six lncRNAs in 19 primary GBM samples, four GBM cell lines and in-house developed TMZ-resistant GBM cells. Results: Elevated levels of Hotair and H19 were observed in primary GBM tumors while decreased expression of MEG3 was recorded in the same samples. Interestingly, levels of PANDA increased 3.4-fold in GBM cells resistant to TMZ when compared with their sensitive counterparts. Conclusions: Overall, this work provides evidence of lncRNA deregulation in GBM tumors and reveals a previously unexplored lncRNA potentially involved in TMZ resistance. Modulation of lncRNA targets via RNAi-mediated approaches is envisioned to clarify their function and to strengthen their position as therapeutic options in GBMs.

Circulating HOTAIR expression predicts the clinical response to neoadjuvant chemotherapy in patients with breast cancer.

Long noncoding RNA HOTAIR has been detected in the serum of patients with various malignances and may be served as novel biomarker for diagnosis and prognosis prediction of breast cancer. However, the value of circulating HOTAIR to predict the response to neoadjuvant chemotherapy (NAC) remains unclear. In the present study, we analyzed whether pretreatment circulating HOTAIR levels predict the response to NAC and investigated prognostic impact of circulating HOTAIR on disease-free survival (DFS) in breast cancer patients treated with NAC. Circulating HOTAIR levels in the serum of 112 breast cancer patients before NAC were measured using quantitative real-time PCR. The correlation of circulating HOTAIR with the clinicopathologic status and the response to NAC were analyzed. Kaplan-Meier survival analysis and log-rank test were used to estimate the DFS. In 112 serum samples obtained before NAC, high circulating HOTAIR was associated with larger tumor size, more positive lymph nodes as well as more distant metastasis. However, there was no significant correlation between the circulating HOTAIR levels and age, Ki67 status or hormone receptor. Furthermore, patients with high circulating HOTAIR achieved less clinical response as well as pathologic complete response than those with low circulating HOTAIR (p< 0.05). The Kaplan-Meier survival curve with a median follow-up of 48 months demonstrated that patients with high circulating HOTAIR expression had a worse disease-free survival than those with low circulating HOTAIR (log-rank p= 0.012). High circulating HOTAIR level correlates with less response to neoadjuvant chemotherapy as well as a worse prognosis in breast cancer patients. Therefore, the present study provides a favorable basis to use circulating HOTAIR as a predictor of neoadjuvant chemotherapy response.

Low expression of long noncoding RNA MT1JP is associated with poor overall survival in gastric cancer patients: Protocol for meta-analysis.

Background:Although several researches have investigated the association between development and metastasis of gastric cancer (GC) and the expression level of MT1JP, there are no consensuses about whether its expression is associated with overall survival (OS) and clinical feature for GC patients.Methods:The databases including PubMed, EMBase databases, and the Cochrane Library were searched from inception to January 30, 2016, to identify the eligible studies. The quality of included studies was assessed according to reporting recommendations for tumor marker prognostic studies (REMARK). The association between expression level of LncRNA HOTAIR with OS for GC patients was assessed by calculating the pooled hazard ratio (HR) and 95% confidence interval (95% CI) using STATA version 12.0. Heterogeneity among studies will be assessed using the I2 statistic.Results:Randomized controlled trials (RCTs), prospective cohort studies, and case–control studies will be used for the qualitative and quantitative synthesis of the meta-analysis to explore the association between MT1JP expression levels with OS for gastric cancer patients.Conclusion:We aim to draw an objective conclusion of the association between MT1JP expression levels with OS for gastric cancer patients.

ARFHPV E7 oncogene, lncRNA HOTAIR, miR-331-3p and its target, NRP2, form a negative feedback loop to regulate the apoptosis in the tumorigenesis in HPV positive cervical cancer.

The objective of this study was to explore the role of HOTAIR in the development of cervical cancer, as well as its downstream signaling pathway. We conducted computational analysis, luciferase assay to explore downstream of HOTAIR and miR-331-3p. Real-time PCR and Western blot were carried out to detect the relationship among E7, HOTAIR, miR-331-3p, NRP2, and P53. Finally, MTT assay and flow cytometry analysis were performed to validate the effect of E7 and miR-331-3p on cell apoptosis and proliferation. NRP2 was identified as a virtual target gene of miR-331-3p with a binding site of miR-331-3p, and HOTAIR was directly sponged to miR-331-3p, miR-331-3p reduced luciferase activity of wild-type of NRP2 3'UTR and HOTAIR, but not those of mutant NRP2 3'UTR and HOTAIR. MiR-331-3p down-regulated NRP2 and E7 expression levels, and further promoted cell apoptosis, while inhibited cell proliferation. Cell transfected with HPV16 E7 displayed lower levels of HOTAIR, NRP2 and P53, a higher level of miR-331-3p, over-expression of E7 further repressed cell apoptosis, while improved cell proliferation compared with control. Normal HPV (+) group exhibited a higher miR-331-3p, and lower mRNA levels of HOTAIR and NRP2 than HPV (-) group. According to the result of IHC (immunohistochemistry), we found that NRP2 protein was highly expressed in HPV (-) group compared to that in HPV (+) group. E7-HOTAIR-miR-331-3p-NRP2-E7 formed a regulatory loop, and could be involved in the pathogenesis of cervical cancer.

The long non-coding RNA HOTAIR is transcriptionally activated by HOXA9 and is an independent prognostic marker in patients with malignant glioma.

The lncRNA HOTAIR has been implicated in several human cancers. Here, we evaluated the molecular alterations and upstream regulatory mechanisms of HOTAIR in glioma, the most common primary brain tumors, and its clinical relevance. HOTAIR gene expression, methylation, copy-number and prognostic value were investigated in human gliomas integrating data from online datasets and our cohorts. High levels of HOTAIR were associated with higher grades of glioma, particularly IDH wild-type cases. Mechanistically, HOTAIR was overexpressed in a gene dosage-independent manner, while DNA methylation levels of particular CpGs in HOTAIR locus were associated with HOTAIR expression levels in GBM clinical specimens and cell lines. Concordantly, the demethylating agent 5-Aza-2′-deoxycytidine affected HOTAIR transcriptional levels in a cell line-dependent manner. Importantly, HOTAIR was frequently co-expressed with HOXA9 in high-grade gliomas from TCGA, Oncomine, and our Portuguese and French datasets. Integrated in silico analyses, chromatin immunoprecipitation, and qPCR data showed that HOXA9 binds directly to the promoter of HOTAIR. Clinically, GBM patients with high HOTAIR expression had a significantly reduced overall survival, independently of other prognostic variables. In summary, this work reveals HOXA9 as a novel direct regulator of HOTAIR, and establishes HOTAIR as an independent prognostic marker, providing new therapeutic opportunities to treat this highly aggressive cancer.

LncRNA HOTAIR influences cell growth, migration, invasion, and apoptosis via the miR-20a-5p/HMGA2 axis in breast cancer.

To study the regulatory effect of lncRNA HOTAIR/miR‐20a‐5p/HMGA2 axis on breast cancer (BC) cell growth, cell mobility, invasiveness, and apoptosis. The microarray data of lncRNAs and mRNAs with differential expression in BC tissues were analyzed in the Cancer Genome Atlas (TCGA) database. LncRNA HOX transcript antisense RNA (lncRNA HOTAIR) expression in BC was assessed by qRT‐PCR. Cell viability was confirmed using MTT and colony formation assay. Cell apoptosis was analyzed by TdT‐mediated dUTP nick‐end labeling (TUNEL) assay. Cell mobility and invasiveness were testified by transwell assay. RNA pull‐down and dual luciferase assay were used for analysis of the correlation between lncRNA HOTAIR and miR‐20a‐5p, as well as relationship of miR‐20a‐5p with high mobility group AT‐hook 2 (HMGA2). Tumor xenograft study was applied to confirm the correlation of lncRNA HOTAIR/miR‐20a‐5p/HMGA2 axis on BC development in vivo. The expression levels of the lncRNA HOTAIR were upregulated in BC tissues and cells. Knockdown lncRNA HOTAIR inhibited cell propagation and metastasis and facilitated cell apoptosis. MiR‐20a‐5p was a target of lncRNA HOTAIR and had a negative correlation with lncRNA HOTAIR. MiR‐20a‐5p overexpression in BC suppressed cell growth, mobility, and invasiveness and facilitated apoptosis. HMGA2 was a target of miR‐20a‐5p, which significantly induced carcinogenesis of BC. BC cells progression was mediated by lncRNA HOTAIR via affecting miR‐20a‐5p/HMGA2 in vivo. LncRNA HOTAIR affected cell growth, metastasis, and apoptosis via the miR‐20a‐5p/HMGA2 axis in breast cancer.

LncRNA HOTAIR promotes cell migration and invasion by regulating MKL1 via inhibition miR206 expression in HeLa cells

BackgroundLong non-coding RNAs (lncRNAs) have emerged as a new and crucial layer of gene regulation in recent years and regulate various biological processes such as carcinogenesis and metastasis. LncRNA HOTAIR, an oncogenic lncRNA, is involved in human tumorigenesis and dysregulated in cervical cancer. Megakaryoblastic leukemia 1 (MKL1), as a transcription coactivity factor, involved in cancer metastasis and cell differentiation. However, the precise mechanism of biological roles of HOTAIR and MKL1 in cancer cells remain unclear.MethodsThe expression levels of HOTAIR and MKL1 were measured by quantitative PCR (qPCR), immunoblotting, in situ hybridization (ISH) and immunohistochemistry (IHC). Wound-healing and transwell assays were used to examine the invasive abilities of HeLa cells. Luciferase reporter assays and CHIP were used to determine how MKL1 regulates HOTAIR. Tissue microarray and immunohistochemical staining were used to assess the correlation between HOTAIR and MKL1 in Cervical cancer tissues in vivo.ResultIn this study, we have identified that MKL1 had a role in the induction of migration and invasion in cervical cancer cells. Moreover, the expression level of MKL1, as the targeting gene of miR206, was decreased after HOTAIR inhibition in HeLa cells. Agreement with it, Highly level of MKL1 correlation with HOTAIR is validated in cervical cancer tissues. Importantly, HOTAIR is observed to participate in the silencing of miR206 expression. Interestingly, HOTAIR inhibition could also accelerate the expression of MKL1 in cytoplasm. What is more, MKL1 can activate the transcription of HOTAIR through binding the CArG box in the promoter of HOTAIR.ConclusionThese elucidates that the phenotypic effects of migration and invasion observed after HOTAIR inhibition, at least in part, through the regulation of MKL1 via inhibition of miR206 expression in HeLa cells. These data indicate the existence of a positive feedback loop between HOTAIR and MKL1. Together, these findings suggest that MKL1 is an important player in the functions of HOTAIR in the migration and invasion of cancer cells.

Long non-coding RNA HOTAIR promotes UVB-induced apoptosis and inflammatory injury by up-regulation of PKR in keratinocytes

Excessive exposure to ultraviolet (UV) rays can cause damage of the skin and may induce cancer, immunosuppression, photoaging, and inflammation. The long non-coding RNA (lncRNA) HOX antisense intergenic RNA (HOTAIR) is involved in multiple human biological processes. However, its role in UVB-induced keratinocyte injury is unclear. This study was performed to investigate the effects of HOTAIR in UVB-induced apoptosis and inflammatory injury in human keratinocytes (HaCaT cells). Quantitative real-time polymerase chain reaction was performed to analyze the expression levels of HOTAIR, PKR, TNF-α, and IL-6. Cell viability was measured using trypan blue exclusion method and cell apoptosis using flow cytometry and western blot. ELISA was used to measure the concentrations of TNF-α and IL-6. Western blot was used to measure the expression of PKR, apoptosis-related proteins, and PI3K/AKT and NF-κB pathway proteins. UVB induced HaCaT cell injury by inhibiting cell viability and promoting cell apoptosis and expressions of IL-6 and TNF-α. UVB also promoted the expression of HOTAIR. HOTAIR suppression increased cell viability and decreased apoptosis and expression of inflammatory factors in UVB-treated cells. HOTAIR also promoted the expression of PKR. Overexpression of HOTAIR decreased cell viability and increased cell apoptosis and expression of inflammatory factors in UVB-treated cells by upregulating PKR. Overexpression of PKR decreased cell viability and promoted cell apoptosis in UVB-treated cells. Overexpression of PKR activated PI3K/AKT and NF-κB pathways. Our findings identified an essential role of HOTAIR in promoting UVB-induced apoptosis and inflammatory injury by up-regulating PKR in keratinocytes.

Involvement of aberrantly activated HOTAIR/EZH2/miR-193a feedback loop in progression of prostate cancer

BackgroundThough androgen deprivation therapy is the standard treatment for prostate cancer (PCa), most patients would inevitably progress to castration-resistant prostate cancer (CRPC) which is the main cause of PCa death. Therefore, the identification of novel molecular mechanism regulating cancer progression and achievement of new insight into target therapy would be necessary for improving the benefits of PCa patients. This study aims to study the function and regulatory mechanism of HOTAIR/EZH2/miR-193a feedback loop in PCa progression.MethodsMSKCC and TCGA datasets were used to identify miR-193a expression profile in PCa. Cell Counting Kit-8 (CCK-8) assays, colony formation, invasion, migration, flow cytometry, a xenograft model and Gene Set Enrichment Analysis were used to detect and analyze the biological function of miR-193a. Then, we assessed the role of HOTAIR and EZH2 in regulation of miR-193a expression by using plasmid, lentivirus and small interfering RNA (siRNA). Luciferase reporter assays and chromatin immunoprecipitation assays were performed to detect the transcriptional activation of miR-193a by EZH2 and HOTAIR. Further, qRT-PCR and luciferase reporter assays were conducted to examine the regulatory role of miR-193a controlling the HOTAIR expression in PCa. Finally, the correlation between HOTAIR, EZH2 and miR-193a expression were analyzed using In situ hybridization and immunohistochemistry.ResultsWe found that miR-193a was significantly downregulated in metastatic PCa through mining MSKCC and TCGA datasets. In vitro studies revealed that miR-193a inhibited PCa cell growth, suppressed migration and invasion, and promoted apoptosis; in vivo results demonstrated that overexpression of miR-193a mediated by lentivirus dramatically reduced PCa xenograft tumor growth. Importantly, we found EZH2 coupled with HOTAIR to repress miR-193a expression through trimethylation of H3K27 at miR-193a promoter in PC3 and DU145 cells. Interestingly, further evidence illustrated that miR-193a directly targets HOTAIR showing as significantly reduced HOTAIR level in miR-193a overexpressed cells and tissues. The expression level of miR-193a was inversely associated with that of HOTAIR and EZH2 in PCa.ConclusionThis study firstly demonstrated that miR-193a acted as tumor suppressor in CRPC and the autoregulatory feedback loop of HOTAIR/EZH2/miR-193a served an important mechanism in PCa development. Targeting this aberrantly activated feedback loop may provide a potential therapeutic strategy.

LncRNA HOTAIR contributes to the tumorigenesis of nasopharyngeal carcinoma via up-regulating FASN.

The therapeutic options for nasopharyngeal carcinoma (NPC) treatment have been restricted mainly to radiotherapy or chemotherapy, and the clinical treatment effect remains unsatisfactory. The primary purpose of this study was to investigate the molecular mechanisms of NPC and to find effective novel therapeutic targets for NPC. In order to analyze the expression level of lncRNA HOTAIR and FASN in human NPC clinical tissues or NPC cells, total RNA was extracted with TRIzol and the relative mRNA expression levels were detected by quantitative Real-time PCR. The endogenous expression of HOTAIR was modulated using lentivirus vectors transfection. The protein levels of Fatty acid synthase (FASN), p21 and MMP-9 in NPC cells were determined by Western blot when HOTAIR was knockdown. A free Fatty acid quantitation assay was performed to detect the intracellular free Fatty acid in NPC cells. The CCK-8 and colony formation assays were performed for cell viability and proliferation determination. The cell cycle of NPC cells was also determined by flow cytometric analysis. A matrigel invasion assay was performed to analyze the invasive ability of NPC cells. In this study, we observed a significant upregulation of lncRNA HOTAIR in NPC cells and clinical NPC specimens. The expression of Fatty acid synthase (FASN) was positively correlated to HOTAIR in NPC specimens. Knockdown of HOTAIR led to downregulation of FASN in NPC cells, thus suppressing cell proliferation and invasion. Additionally, de novo synthesis of cellular free fatty acid in NPC cells was inhibited when HOTAIR was knockdown. Furthermore, the protein levels of MMP-9 and p21 were downregulated when HOTAIR was knockdown. We suggest that HOTAIR is important in the progression and recurrence of NPC, perhaps through upregulating FASN. Targeting HOTAIR may be an effective therapeutic strategy for NPC.

Serum HOTAIR and GAS5 levels as predictors of survival in patients with glioblastoma.

Circulating long non-coding RNAs (lncRNAs) are a new class of cancer biomarkers. However, their significance in predicting outcomes in glioblastoma patients is unclear. We measured the levels of six known oncogenic lncRNAs-CRNDE, GAS5, H19, HOTAIR, MALAT1, and TUG1 in serum samples from 106 patients with primary glioblastoma and analyzed their association with outcomes. High levels of HOTAIR were associated with decreased probability of 2-year overall survival (adjusted hazard ratio [HR] = 2.04; 95% confidence interval [CI] = 1.08-9.76), and disease-free survival (adjusted HR = 1.82; 95% CI = 1.04-6.17). High levels of GAS5 were associated with increased probability of 2-year overall survival (adjusted HR = 0.44; 95% CI = 0.18-0.99), and disease-free survival (adjusted HR = 0.46; 95% CI = 0.16-0.98). HOTAIR and GAS5 levels could serve as reciprocal prognostic predictors of survival and disease progression in patients with glioblastoma.

Gemcitabine treatment causes resistance and malignancy of pancreatic cancer stem-like cells via induction of lncRNA HOTAIR.

Gemcitabine is the first-line chemotherapeutic agent for advanced adenocarcinoma of the pancreas, despite the high risk of chemoresistance as a major disadvantage. In the past few years, significant advances have been made in the field of pancreatic cancer stem-like cells (CSCs) and their critical roles in drug resistance, invasion and metastasis, which are tightly regulated by long non-coding RNAs (lncRNAs). The present study demonstrated that HOX antisense intergenic RNA (HOTAIR) is not different between the pancreatic cancer cell line PANC-1 and its enriched CSC sub-population. However, after gemcitabine treatment, the expression levels of HOTAIR in CSCs were induced, but not in PANC-1 cells. HOTAIR induced by gemcitabine failed to cause chemoresistance, but promoted the clonogenicity, proliferation and migration of the cells. By introducing HOTAIR using lentivirus, chemoresistance was induced and the self-renewal capacity, proliferation and migration were significantly promoted. By contrast, HOTAIR knockdown in PANC-1 CSCs treated with or without gemcitabine decreased the cell proliferation, altered the cell cycle progression and induced apoptosis, demonstrating its critical roles in regulating the malignant character of PANC-1 CSCs. In conclusion, the present study demonstrated that HOTAIR may be induced by gemcitabine and acts as a tumor promoter by inhibiting the chemosensitivity, and promoting the self-renewal capacity, proliferation and migration of PANC-1 CSCs, which supports its potential application as a novel therapeutic approach for pancreatic cancer.

Abstract 3481: Leveraging protein coding gene expression profiles to accurately impute lncRNA transcriptome of cancer cells

Abstract Long noncoding RNAs (lncRNAs) represent a large, diverse and tissue-specific class of transcripts that are involved in gene regulation. Recent large-scale cancer sequencing efforts indicate that lncRNAs are an important component of the cancer transcriptome, and may play a critical role in carcinogenesis and drug sensitivity. Accurate profiling of lncRNAs however remains a challenge owing to significantly lower expression levels than mRNA, requiring deep paired-end total RNA sequencing, which can be prohibitively expensive. Additionally, previous generation microarrays that constitute a vast majority of GEO and ArrayExpress datasets do not provide comprehensive lncRNA coverage. Here we propose a lncRNA expression imputation (LEXI) framework to reconstruct the lncRNA transcriptome of cancer cells using their mRNA expression profiles. Our goal is to provide a tool that enables the harnessing of enormous wealth of publicly available cancer mRNA datasets and discover novel lncRNAs associated with carcinogenesis and drug sensitivity. The LEXI approach is based on learning patterns of mRNA expression associated with each lncRNA across a diverse cohort of cancer cells and then predict lncRNA expression profile of uncharacterized cells. We developed LEXI by evaluating the performance of various machine-learning algorithms benchmarked in a cross-validation study across a cohort of 675 cancer cell lines and 9755 pan-cancer tissues. We adapted the LEXI framework based on optimal performance and computation time and show that LEXI accurately predicts lncRNA expression profiles in both cell lines and tissues. To demonstrate the utility of LEXI, we reconstruct the lncRNA transcriptome of over 1000 cell lines and 2000 TCGA samples, and compare with RNAseq measured lncRNA levels in corresponding samples. We further show expression levels of MALAT1, HOTAIR, CCAT1 and other established cancer-associated lncRNAs are accurately predicted across cancer types, and can be used to discover novel associations in uncharacterized phenotypes. LEXI will be available as a free resource for researchers to easily obtain lncRNA profiles using their own mRNA data. Citation Format: Aritro Nath, Paul Geeleher, R. Stephanie Huang. Leveraging protein coding gene expression profiles to accurately impute lncRNA transcriptome of cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3481. doi:10.1158/1538-7445.AM2017-3481

Expression of Serum LncRNA HOTAIR in Non-small Cell Lung Cancer and Its Clinical Significance

背景与目的长链非编码RNA HOX转录反义RNA（HOX transcript antisense RNA, HOTAIR）在多种肿瘤中异常表达。本研究旨在探讨非小细胞肺癌（non-small cell lung cancer, NSCLC）患者血清中lncRNA HOTAIR的水平及其临床意义。方法采用实时定量聚合酶链反应（polymerase chain reaction, PCR）方法检测64例NSCLC患者和64例正常对照血清中HOTAIR的水平，统计分析血清中HOTAIR的水平与NSCLC临床病理参数之间的关系。结果与正常对照组相比，NSCLC患者血清中HOTAIR水平明显升高，两组之间的差异具有统计学意义（P < 0.01）。血清中HOTAIR水平与NSCLC患者的肿瘤大小、（tumor-node-metastasis, TNM）分期及淋巴转移有关（P < 0.05），而与患者的年龄、性别、吸烟、分化程度及病理类型均无明显相关（P > 0.05）。结论NSCLC患者血清中HOTAIR水平明显升高，HOTAIR可能参与了NSCLC的发病过程。

HOTAIR role in melanoma progression and its identification in the blood of patients with advanced disease.

The molecular mechanisms responsible for the metastatic progression of melanoma have not been fully defined yet. We have recently shown that an important role in this process is certainly played by HOX genes, whose regulation is under control of particular non-coding RNAs, some of which are present within the HOX locus. HOTAIR is the most studied among them, whose aberrant expression is associated with the metastatic progression of many malignancies. The aim of this study was to verify the role played by HOTAIR in metastatic progression of melanoma and to evaluate the circulating levels of HOTAIR in the blood of patients with metastatic melanoma. A series of melanocytic lesions were selected to evaluate the potential changes in the expression of HOTAIR during the evolution of the disease through in situ and molecular approaches. None of the benign melanocytic lesions showed the presence of HOTAIR. The staining of HOTAIR resulted very weak in the primary pT1 lesions, while it was very strong in all pairs of primary tissues and corresponding metastases. Surprisingly, we found the presence of HOTAIR in some intratumoral lymphocytes, while this positivity decreased in lymphocyte component further away from the tumor. HOTAIR was also detected in the serum of selected metastatic patients. These data allowed us to speculate on the fundamental role played by HOTAIR in tumor evolution of melanoma. Its presence in intratumoral lymphocytes might suggest that its involvement in the modulation of tumor microenvironment and the detection in the serum could be used in the management of melanoma patients.

Study of long non-coding RNA HOTAIR expression in middle ear cholesteatoma

Objective:To discuss the different expression of some long-chain noncoding RNA between middle ear cholesteatoma epithelial tissue and normal external ear canal skin.Method:Real-time quantitative PCR was used to detect the expression of 6 kinds of lncRNA: HOTAIR, ANCR, TINCR, PRINS, BANCR, PICSAR in 25 cases of cholesteatoma epithelial tissues and 15 cases of normal external auditory canal skin tissue samples, respectively. And compared the expression level of lncRNA in patients with different degree of bone destruction.Result:Expression level of HOTAIR was significantly increased in cholesteatoma epithelial tissues compared with the normal external auditory canal skin tissues,and the difference is statistically significant (P< 0.01). While there was no statistically significant difference expression of the rest of the five kinds of lncRNA between middle ear cholesteatoma epithelial tissues and normal external ear canal skin (P> 0.05). And there was no statistically significant difference expression of HOTAIR in patients with different degree of bone destruction (P> 0.05).Conclusion:Expression level of HOTAIR was up-regulated in middle ear cholesteatoma epithelial tissue compared with the normal external auditory canal skin tissues, and the expression level of HOTAIR has no obvious correlation with degree of bone destruction in patients with cholesteatoma.

Long non-coding RNA HOTAIR inhibits miR-17-5p to regulate osteogenic differentiation and proliferation in non-traumatic osteonecrosis of femoral head.

Background and aimThe biological functions of non-coding RNAs (ncRNAs) have been widely identified in many human diseases. In the present study, the relationship between long non-coding RNA HOTAIR and microRNA-17-5p (miR-17-5p) and their roles in osteogenic differentiation and proliferation in non-traumatic osteonecrosis of femoral head (ONFH) were investigated.MethodsThe expression levels of HOTAIR and miR-17-5p in the mesenchymal stem cells (MSCs) derived from patients with non-traumatic ONFH and osteoarthritis (OA) were examined by real-time PCR. BMP-2 induced human MSCs from bone marrow (hMSC-BM) were used for osteogenic differentiation.ResultsIt was observed that the expression level of miR-17-5p was lower and the level of HOTAIR was higher in samples of non-traumatic ONFH compared with OA. HOTAIR downregulation induced by si-HOTAIR led to the increase of miR-17-5p expression and the decrease of miR-17-5p target gene SMAD7 expression. The values of osteogenic differentiation markers, including RUNX2 and COL1A1 mRNA expression and ALP activity, were also elevated by si-HOTAIR. However, the increase of these values was canceled by miR-17-5p inhibitor or SMAD7 upregulation.ConclusionHOTAIR played a role in regulating osteogenic differentiation and proliferation through modulating miR-17-5p and its target gene SMAD7 in non-traumatic ONFH.

LncRNAs as an intermediate in HPV16 promoting myeloid-derived suppressor cell recruitment of head and neck squamous cell carcinoma.

The emerging evidence showed that long noncoding RNAs (lncRNAs) are involved in cell growth and apoptosis as well as cancer progression and metastasis of malignant tumor, however, limited data are available on the role of lncRNAs in human papillomavirus (HPV)-associated Head and neck squamous cell carcinomas (HNSCC). Here, we demonstrated that 23.98% of 196 HNSCC cases in Southwest China could be classified as HPV16 infection. The number of MDSCs in HPV-positive HNSCC was significantly higher than normal control, indicating that HPV infection may promote MDSCs aggregation. Then, we applied an array-based approach to monitor the lncRNA expression between HPV-positive HNSCC, HPV-negative HNSCC and normal oral mucous, and obtained 132 different lncRNAs in different HPV infected states of HNSCC. HOTAIR, PROM1, CCAT1, and MUC19 mRNA levels, determined by qRT-PCR were inversely correlated with MDSCs collection of HPV-associated HNSCC in 2 independent patient cohorts. The results may provide a rationale for the further evaluation of lncRNAs as a molecular target to elucidate the molecular mechanism of HPV promoting MDSCs collection of HNSCC.

Circulating Long Noncoding RNA HOTAIR is an Essential Mediator of Acute Myocardial Infarction

Background/Aims: Acute myocardial infarction (AMI) is one of the leading causes of death in the world. However, specific diagnostic biomarkers have not been fully determined, and candidate regulatory targets for AMI have not been identified to date. Long noncoding RNAs (lncRNAs) are a class of RNA molecules that have diverse regulatory functions during embryonic development, normal life, and disease in higher organisms. However, research on the role of lncRNAs in cardiovascular diseases, particularly AMI, is still in its infancy. HOX antisense intergenic RNA (HOTAIR), a 2.2 kb lncRNA, was initially described as a modulator of HOX gene expression. Recent studies have illustrated the important role of HOTAIR in cancer progression, but few studies have reported its function in cardiac disease, including AMI. In the current study, we aimed to detect the expression of HOTAIR during AMI and to explore its function in hypoxia-induced cardiomyocyte injury in neonatal cardiomyocytes. Methods: In 50 consecutively enrolled AMI patients, we examined the serum expression levels of HOTAIR and analysed its correlation with cardiac troponin I (cTnI) expression. Another 50 age- and sex-matched subjects served as healthy controls. Next, the HOTAIR expression was detected in the serum from C57BL/6J mice subjected to coronary artery ligation and in neonatal rat cardiomyocytes induced by hypoxia. Cultured cardiomyocytes apoptosis were measured by terminal deoxynucleotide transferase dUTP nick end labelling (TUNEL) staining. A search for miRNAs that had complementary base paring with HOTAIR was performed utilizing an online software program, and the interaction between miR-1 and HOTAIR was examined using a luciferase reporter assay. Results: Our study revealed that HOTAIR expression was significantly decreased in the serum of AMI patients compared with that of the healthy controls. Similarly, we observed that HOTAIR was downregulated in the serum of mice subjected to coronary artery ligation and in cultured cardiomyocytes exposed to hypoxia. Furthermore, we observed that the adenovirus vector-driven overexpression of HOTAIR dramatically limited hypoxia-induced myocyte apoptosis, whereas knockdown HOTAIR by AdshHOTAIR (adenoviral short hairpin HOTAIR) exhibited the opposite phenotype. Mechanistically, we discovered that the cardioprotective function of HOTAIR is partly based on the negative regulation of miR-1. Conclusions: Taken together, the results of our study suggest that HOTAIR is a protective factor for cardiomyocytes and that the plasma concentration of HOTAIR may serve as a biomarker for human AMI diagnosis.

Elevated HOTAIR expression associated with cisplatin resistance in non-small cell lung cancer patients

This study investigated the mechanism of drug resistance in non-small cell lung cancer (NSCLC) patients. We specifically studied whether long noncoding RNAs influence drug resistance in NSCLC to discover new therapeutic targets to increase the survival rate of drug-resistant NSCLC patients. Tissue samples were collected from NSCLC patients, and total RNA was isolated for assessment of HOTAIR expression and drug resistance status. MTT assays, tumor sphere formation assays, and western blot were performed to cytologically determine the relationship between HOTAIR expression and cisplatin resistance, as well as to elucidate the potential molecular mechanism involved. HOTAIR expression in tissues of drug-resistant NSCLC patients was higher than that of non-drug-resistant patients. HOTAIR expression was elevated in cisplatin-resistant cell strains (A549/CDDP), and reducing HOTAIR expression increased the sensitivity of A549/CDDP cells to cisplatin. In addition, overexpression of HOTAIR in A549 cells increased resistance to cisplatin. Tumor sphere formation assays showed that the volume of spheres formed by cell strains expressing elevated levels of HOTAIR was greater than that of cell strains with low expression. Western blot experiments showed that elevated expression of HOTAIR upregulated tumor stem cell-related biomarkers and HOTAIR expression was directly related to Klf4 expression. Elevated HOTAIR expression is associated with drug resistance in NSCLC patients and is related to Klf4 upregulation, providing a new therapeutic target for drug-resistant NSCLC patients.