lncRNA HOTAIR Research Articles

HoxC6 Functions as an Oncogene and Isoform HoxC6-2 May Play the Primary Role in Gastric Carcinogenesis.

Based on previous researches of HoxC6, this study aims to investigate the expression levels of isoforms HoxC6-1 and HoxC6-2 and to explore their roles in gastric carcinogenesis as well as the possible molecular mechanism. We investigated expression levels of HoxC6, HoxC6-1, and HoxC6-2 in gastric cancer tissues, coupled with relevant data in TCGA dataset. In vitro, HoxC6, HoxC6-1, and HoxC6-2 knockdown by small interference RNA was carried for evaluating the changes of malignant biological behaviors of gastric cancer cells, such as proliferation, migration, invasion, apoptosis, and cell cycle alternation. Metastasis-related nucleotide lncRNA HOTAIR was selected by bioinformatics, and verification was carried out by in vitro researches. Data suggested HoxC6-1 and HoxC6-2 were considerably over-expressed with different folds in gastric cancerous tissues. Decreased expression of HoxC6-2 was detected in well-differentiated type of gastric cancer. In vitro, the conclusion that HoxC6 functions as a tumor oncogene illuminated by previous studies was verified again. Additionally, down-regulating of HoxC6-2 significantly inhibited SGC-7901 and BGC-823 cells from proliferation, migration, invasion, apoptosis, while quite slight results or none statistically significant results were observed when HoxC6-1 was knockdown. Besides, over-expression of HOTAIR, which is relevant with HoxC6 during gastric carcinogenesis, was detected in gastric cancerous tissues. Restored expression of HoxC6 partially reversed the decreased migration caused by down-regulating HOTAIR in gastric cancer cells. HoxC6 acts as an oncogene in gastric carcinogenesis and might be a promising therapeutic target. Isoform HoxC6-2 plays a primary carcinogenic role in gastric carcinogenesis. HOTAIR, over-expressed in gastric cancer, might regulate HoxC6 on the protein level in promoting migration of gastric cells.

HOTAIR Promotes Cisplatin Resistance of Osteosarcoma Cells by Regulating Cell Proliferation, Invasion, and Apoptosis via miR-106a-5p/STAT3 Axis

Osteosarcoma (OS) is a common primary malignant bone tumor among adolescences, and the emergence of multidrug resistance poses a huge challenge for clinical treatment of OS. LncRNA HOTAIR (HOX antisense intergenic RNA) has been reported to be associated with many malignancies, including OS. However, the underlying mechanisms of HOTAIR involved in drug resistance in OS are obscure. Our study showed that HOTAIR was upregulated in cisplatin (DDP)-resistant OS tissues and cells. HOTAIR knockdown decreased the DDP resistance, drug resistance–related gene expression, cell proliferation, and invasion and promoted apoptosis of Saos2/DDP, MG-63/DDP, and U2OS/DDP cells. Mechanism researches displayed that miR-106a-5p was downregulated in DDP-resistant OS tissues and cells. MiR-106a-5p directly bound with HOTAIR and was regulated by HOTAIR. Moreover, STAT3 was inhibited by miR-106a-5p at a post-transcriptional level, and the transfection of miR-106a-5p reversed the upregulation of STAT3 caused by HOTAIR overexpression. The increase or decrease of miR-106a-5p suppressed the effect of HOTAIR upregulation or downregulation on DDP resistance, cell proliferation, invasion, and apoptosis of Saos2/DDP, MG-63/DDP, and U2OS/DDP cells. What’s more, the transfection of STAT3 siRNA reversed the decrease of DDP resistance, cell proliferation, and invasion and rescued the increase of apoptosis induced by miR-106a-5p inhibition. These data suggested that HOTAIR enhanced DDP resistance of Saos2/DDP, MG-63/DDP, and U2OS/DDP cells by affecting cell proliferation, invasion, and apoptosis via miR-106a-5p/STAT3 axis.

The prognostic impact of abnormally expressed, long noncoding RNAs in acute myeloid leukemia: a meta-analysis

ABSTRACT Objectives: A growing number of studies demonstrate that long noncoding RNAs (lncRNAs) could act as biomarkers to determine the prognosis of acute myeloid leukemia (AML) patients. Nonetheless, the significance of lncRNAs in AML prognosis remains unclear. We conducted a meta-analysis to assess the prognostic indicators of abnormally expressed lncRNAs in AML. Methods: Literature was searched using PubMed, EMBASE, and Web of Science databases up to November 10, 2018. Results: Thirteen studies with 2755 individuals were included. The abnormal expression of lncRNAs was associated with worse overall survival (OS) in AML patients, especially in cytogenetically normal AML (CN-AML), and was associated with shorter disease-free survival and event-free survival. Subgroup analysis showed that high levels of HOTAIR and TUG1 were associated with poor OS. Discussion: Overexpression of lncRNA HOTAIR and TUG1 were reported in two separate studies, and correlated with worse AML prognoses. Conclusion: Abnormally expressed lncRNAs are significantly related to worse prognoses of AML patients and might serve as potential prognostic markers to predict the prognosis of AML patients.

Dynamic Regulative Biomarker: Long Noncoding RNA (lncRNA) in Metastatic Breast Cancer.

Breast tumor is a common cancer in women all over the world. Long noncoding RNA (lncRNA) provides a significant and new perspective on understanding biomarkers as well as on the potential prognostic regulation of breast cancer. Its transcription, in turn, serves as a regulator in diagnosing breast cancer and preventing risk of recurrence. Here, we review the evolution of lncRNAs and discuss their regulative roles in the metastasis of breast cancer. Moreover, we aim to detect the expression level of lncRNA HOTAIR in different stages of breast cancer. Sixty patients with breast cancer at different stages were divided into four groups based on different stages. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression level of lncRNA HOTAIR in breast tumor tissue. Compared to stage I breast cancer, the expression profiles of lncRNA HOTAIR in stage II, III, IV breast cancer are significantly elevated (p < 0.05). The expression profiles of lncRNA HOTAIR in stage III and IV breast cancer are significantly increased compared with stage II breast cancer. Consistent with microRNAs (miRNA), lncRNAs could function as underlying effective biomarkers to affect the biogenesis and gene control across all lifetime. The interaction between lncRNA and miRNA plays a crucial role in the metastasis of breast cancer and provides a potential biomarker target for breast cancer metastasis therapy. Our study has also demonstrated that the expression profiles of lncRNA HOTAIR in stage II, III, IV breast cancer are significantly elevated.

Upregulation of PUM1 Expression in Preeclampsia Impairs Trophoblast Invasion by Negatively Regulating the Expression of the lncRNA HOTAIR.

Pumilio (PUM) proteins are members of a highly conserved RNA-binding protein family that posttranscriptionally regulate gene expression in many organisms. However, their roles in the placenta are unclear. In the present study, we report the requirement for the PUM homolog 1 (PUM1) gene in preeclampsia (PE). Immunofluorescence and immunohistochemical data showed that PUM1 was highly expressed in human placental villi from women with PE compared to healthy controls (HCs). Further, PUM1 overexpression repressed, and knockdown enhanced, the invasion and proliferation of trophoblasts. Interestingly, PUM1 knockdown promoted trophoblast invasion in a villous explant culture model, while PUM1 overexpression repressed these effects. Furthermore, lncRNA transcriptome sequencing coupled with RNA immunoprecipitation (RIP) revealed that PUM1 inhibits trophoblast invasion in PE by downregulating the expression of lncRNA HOTAIR. Moreover, PUM1 regulates HOTAIR expression via a posttranscriptional mechanism. Using RNA-protein pull-down and mRNA stability assays, we identified PUM1 as a specific binding partner that decreased the half-life of HOTAIR and lowered the steady-state level of HOTAIR expression, suggesting a novel posttranscriptional regulatory mechanism. Collectively, these findings identified a novel RNA regulatory mechanism, revealing a new pathway governing the regulation of PUM1/HOTAIR in trophoblast invasion in the pathogenesis of PE.

Expression profiles of serum long non-coding RNA in ovarian cancer patients receiving platinum-containing chemotherapy

Abstract Background Long non-coding RNAs (lncRNAs) appear to be one of the key regulators of cellular signaling processes. According to several authors, they play a crucial role in the regulation of the antitumor immune response. Dysregulation of lncRNA profile is associated with carcinogenesis. Alteration of the lncRNA profile in ovarian cancer (OC) tumor tissue was shown. The aim of our study was to identify serum lncRNAs as potential biomarkers in ovarian cancer. Methods The study included 34 patients with verified ovarian cancer II-IV FIGO stage. Blood sampling was performed before treatment and after 3 courses of standard neoadjuvant (paclitaxel 175 mg/m² + carboplatin AUC 6 every 3 weeks) chemotherapy. To isolate free-circulating RNA from serum, the SileksMagNA-Direct magnetic particle kit was used. Analysis of the normalized expression of lncRNA MALAT, HOTAIR and PVT1 was carried out using qPCR method with normalization by 18S. We assessed the correlations between lncRNA levels and the patient age, tumor stage and CA-125 level. For statistical analysis, the ANOVA criterion (Statistika 13.0) was used. Results We have established strong correlations between the HOTAIR plasma level and age (p = 0.120) and CA-125 level (p = 0.082), and weak correlation with a relapse-free period duration (p = 0.167). The level of MALAT strongly correlated with age (p = 0.050) and with a relapse-free period duration (p = 0.014) and weakly correlated with the stage of ovarian cancer (p = 0.140). PVT1 expression did not reliably correlate with any of the studied clinical and biological parameters. Conclusion The revealed relationships between the levels of circulating MALAT and HOTAIR in the blood plasma of patients with OC require further study of these epigenetic regulators in OC carcinogenesis and chemoresistance. Free circulating lncRNA MALAT and HOTAIR, as an element of a liquid biopsy, are potential prognostic and predictive biomarkers for OC. Legal entity responsible for the study The authors. Funding RFBR (project number 19-315-50012). Disclosure All authors have declared no conflicts of interest.

LncRNA HOTAIR regulates the proliferation and apoptosis of vascular smooth muscle cells through targeting miRNA-130b-3p/PPARα axis.

To investigate the role of long non-coding RNA (lncRNA) HOTAIR in influencing the proliferative and apoptotic abilities of vascular smooth muscle cells (VSMCs) by regulating microRNA-130b-3p (miRNA-130b-3p)/peroxisome proliferator-activated receptor alpha (PPARα) axis. The expression levels of HOTAIR, miRNA-130b-3p, and PPARα in VSMCs treated with different doses of ox-LDL for different time points were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The subcellular distribution of HOTAIR in VSMCs was examined. The regulatory effects of HOTAIR, miRNA-130b-3p, and PPARα on the viability and apoptosis of ox-LDL-treated with VSMCs were assessed. The interaction among HOTAIR, miRNA-130b-3p, and PPARα was evaluated through Dual-luciferase reporter gene assay and Western blot. After treatment of different doses of ox-LDL in VSMCs, the levels of HOTAIR and PPARα were gradually downregulated, whereas miRNA-130b-3p was upregulated. The overexpression of HOTAIR reversed the enhanced viability and suppressed apoptosis in ox-LDL-treated VSMCs. HOTAIR was mainly distributed in nucleus of VSMCs. MiRNA-130b-3p was the direct target of HOTAIR and its level was negatively regulated by HOTAIR. Moreover, miRNA-130b-3p could bind to PPARα and could negatively regulate its level. The knockdown of HOTAIR could reverse the regulatory effect of PPARα on the proliferative and apoptotic abilities of VSMCs CONCLUSIONS: HOTAIR reduces the proliferative ability and stimulates the apoptosis in ox-LDL-treated VSMCs by targeting miRNA-130b-3p/PPARα axis.

Exosomes-Derived Long Non-Coding RNA HOTAIR Reduces Laryngeal Cancer Radiosensitivity by Regulating microRNA-454-3p/E2F2 Axis.

BackgroundStudies have revealed exosomes are implicated in tumor microenvironment and tumorigenesis. Emerging evidence suggests long non-coding RNAs (lncRNAs) possess pivotal roles in laryngeal cancer progression. For this study, we aimed to find out the mechanism of exosomes and lncRNA HOTAIR in laryngeal cancer.MethodsLaryngeal cancer cells-derived exosomes were initially extracted, separated and identified. Flow cytometry was applied to detect apoptosis to evaluate the effect of exosomes on cell radiosensitivity. Dual luciferase reporter gene assay, RNA pull-down and RNA immunoprecipitation assays were conducted to verify the interactions among HOTAIR, microRNA (miR)-454-3p and E2F2. The gain-and-loss functions of HOTAIR or miR-454-3p were carried out to explore their effects on TU212 and LLN cell viability, apoptosis and radiosensitivity. Levels of HOTAIR, miR-454-3p and E2F2 were detected after different treatments. An in vivo analysis was carried out in mice bearing laryngeal cancer xenografts.ResultsLaryngeal cancer-derived exosomes reduced laryngeal cancer cell radiosensitivity. HOTAIR expression was increased after cells were treated with exosome, and HOTAIR overexpression reduced laryngeal cancer cell radiosensitivity. Besides, HOTAIR worked as a competing endogenous RNA (ceRNA) of miR-454-3p to regulate E2F2 in laryngeal cancer cells. In vivo results were reproduced in in vivo studies, which demonstrated that HOTAIR knockdown reduced laryngeal cancer cell radiosensitivity by sponging miR-454-3p to silence E2F2.ConclusionExosome-mediated HOTAIR acts as a ceRNA of miR-545-3p to regulate E2F2, thereby negatively regulating the radiosensitivity of laryngeal cancer cells. This study may offer novel insight into laryngeal cancer treatment.

Down-regulated lncRNA HOTAIR alleviates polycystic ovaries syndrome in rats by reducing expression of insulin-like growth factor 1 via microRNA-130a.

It has been found that long noncoding RNA HOTAIR, microRNA‐130a (miR‐130a) and insulin‐like growth factor 1 (IGF1) expression are associated with ovarian cancer, thus, we hypothesised that the HOTAIR/miR‐130a/IGF1 axis might associate with endocrine disorders and biological behaviours of ovarian granulosa cells in rat models of polycystic ovary syndrome (PCOS). PCOS rat models were established by injection of dehydro‐isoandrosterone, followed by treatment of si‐HOTAIR, oe‐HOTAIR, miR‐130a mimics or miR‐130a inhibitors. Serum hormonal levels were determined to evaluate endocrine conditions. The effect of HOTAIR and miR‐130a on activities of isolated ovarian granulosa cells was assessed, as well as the involvement of IGF1.In the ovarian tissues and granulosa cells of PCOS rat models, highly expressed HOTAIR and IGF1 and poorly expressed miR‐130a were identified. In response to oe‐HOTAIR, serum levels of E2, T and LH were increased and serum levels of FSH were reduced; the proliferation of granulosa cells was reduced and apoptosis was promoted; notably, expression of miR‐130a was reduced while expression of IGF1 was increased. The treatment of si‐HOTAIR reversed the situation. Furthermore, the binding of HOTAIR to miR‐130a and targeting relationship of miR‐130a and IGF1 were confirmed. LncRNA HOTAIR up‐regulates the expression of IGF1 and aggravates the endocrine disorders and granulosa cell apoptosis through competitive binding to miR‐130a in rat models of PCOS. Based on our finding, we predict that competitive binding of HOTAIR to miR‐130a may act as a novel target for the molecular treatment of PCOS.

MiR-326 Inhibits Inflammation and Promotes Autophagy in Silica-Induced Pulmonary Fibrosis through Targeting TNFSF14 and PTBP1.

Silicosis is a kind of irreversible pulmonary fibrosis induced by the long-term inhalation of silica particles. The therapeutic strategy based on the microRNAs might be an effective way for the treatment of silicosis. Our previous miRNA microarray data indicated that miR-326 was decreased in the mouse lung tissues of silica-induced pulmonary fibrosis. However, the specific functions of miR-326 on silica-induced pulmonary fibrosis remain unclear. The objective was to determine the expression and the biological effects of miR-326 in silica-induced pulmonary fibrosis. Methods included mouse models of silica-induced pulmonary fibrosis and miR-326 intervention that were established separately to explore the effect of miR-326 in vivo. The cell models of SiO2-treated lung epithelial cells (HBE and A549) and TGF-β1-stimulated lung fibroblast cells (MRC-5 and NIH/3T3) were used to investigate the mechanism of miR-326 in vitro. Hematoxylin and eosin staining was used to evaluate the severity and distribution of fibrosis of mouse lung tissues. Western blot and immunofluorescence assays were performed to measure the downstream molecules of miR-326. Transmission electron microscopy pictures showed the autophagy activity. The results showed miR-326 is down-regulated in the fibrotic lung tissues of silica-treated mice, while increased expression of miR-326 attenuates silica-induced pulmonary fibrosis in vivo. Tumor necrosis factor superfamily-14 (TNFSF14) and polypyrimidine tract-binding protein 1 (PTBP1) are identified as the targets of miR-326. MiR-326 dampens pulmonary inflammation through targeting TNFSF14 and promotes autophagy activity of fibroblasts through targeting PTBP1. LncRNA HOTAIR facilitates inflammation via sponging miR-326. In conclusion, we demonstrate that miR-326 inhibits inflammation and promotes autophagy activity by targeting TNFSF14 and PTBP1 separately to alleviate silica-induced pulmonary fibrosis. Our results might shed new light on the therapeutic strategies for silica-induced pulmonary fibrosis.

LncRNA HOTAIR is a novel endothelial mechanosensitive gene.

To better address whether the long noncoding RNAs (lncRNAs) HOTAIR and HOTTIP are mechanosensitive genes, they were investigated in differentially challenged endothelial cells with respect to a circuit of tensional forces, considering the performance of both arterial and venous endothelial cells. We subjected arterial- and venous-obtained endothelial cells to a circuit of tensional forces within a shear stress model in vitro. Real-time quantitative polymerase chain reaction analysis indicated that microRNA (miRNA)-related processing machinery is significantly required in shear stressed arterial endothelial cell metabolism, which orchestrates miRNA (small noncoding RNA) involvement, and their involvement suggests lncRNA involvement. Of lncRNAs HOTAIR and HOTTIP, only HOTAIR was mechanosensitive considering both arterial and venous endothelial cells, presenting a positive correlation between methylation signature and gene expression. Thereafter, using bioinformatics tools, lncRNA HOTAIR was predicted to modulate miRNA185, miRNA-21, and miRNA23b downregulation. We compared the values of gene expression with a Pearson's correlation test, and expected correlations were observed for miRNA185 (r = 0.8664), miRNA-21 (r = 0.8605), and miRNA23b (0.9128). Taken together, these findings clearly show that lncRNA HOTAIR responds to the shear stress and emerges as a novel mechanosensitive gene in endothelial cells. Altogether, this understanding of mechanosensitive transcriptional and posttranscriptional control involving HOTAIR can also lead to new forms of therapeutic intervention for various diseases, as well as new strategies for tissue engineering and regenerative medicine.

Long non-coding RNA HOTAIR functions as a competitive endogenous RNA to regulate PRAF2 expression by sponging miR-326 in cutaneous squamous cell carcinoma

BackgroundLncRNAs may exert a regulatory effect in tumorigenesis. Although the expression of lncRNA HOTAIR has been confirmed to be notably elevated in the tissues of CSCC, its biological mechanism in CSCC is still unknown.MethodsHOTAIR expression level in CSCC cell lines was monitored via qRT-PCR. Then CCK-8 assay, Transwell assay and EdU assay were adopted to detect cell migration and proliferation. Meanwhile, through bioinformatics analysis and luciferase reporter gene detection, a new target of HOTAIR was identified. Additionally, Western blotting and RIP analysis were adopted to discuss the possible mechanism.ResultsHOTAIR expression in CSCC cell lines exhibited an obvious elevation. Cell function analysis revealed that HOTAIR overexpression remarkably facilitated CSCC cell migration, proliferation and EMT process, which were impeded by down-regulation of HOTAIR. Furthermore, HOTAIR competitively bound to miR-326, so as to positively modulate miR-326 expression.ConclusionsThese results present that HOTAIR, as a ceRNA, regulates PRAF2 expression by competitive binding to miR-326 during CSCC.

Blockage of HOTAIR Reduced Cell Proliferation in Human Ovarian Cancer Cells Through Upregulation of AKT2

Ovarian cancer (OC) is the most leading cause of cancer-related death in women. lncRNA HOTAIR is emerging as an onco-lncRNA that its overexpression provokes progression and metastasis in OC. In this study, we focused on evaluating the efficiency of antisense-based HOTAIR inhibition in OC tumor cells death. We transfected antisense LNA GapmeR into OC cell line (SKOV3). Then, the survival rates of SKOV3 were measured by MTT at all three time points after transfection. Moreover, we examined the expression level of AKT2 in SKOV3 under the influence of GapmeRs using qPCR at 24, 48 and 72 h after transfection. The viability of SKOV3 was significantly reduced over time under the suppression of lncRNA HOTAIR. The qPCR results disclosed the remarkable increase in AKT2 expression level via inhibition of HOTAIR in SKOV3 cell line. Our data imply that inhibition of HOTAIR by antisense LNA GapmeR induced OC cell death. Hence, we concluded that antisense-based strategies might be considered as a potential therapeutic approach in OC treatment.

The mechanism of action of HOX antisense intergenic RNA in gastric cancer

Objective Investigate the mechanism of HOX antisense intergenic RNA (HOTAIR) in the pathogenesis of gastric cancer. Methods 40 patients with gastric cancer were selected, there were 29 males and 21 females with an average age of (51.7±10.8) years; Ⅰ period 20 cases, Ⅱ period 10 cases, Ⅲ period 6 cases, Ⅳ period 4 cases; 9 cases of high differentiation, 12 cases of middle differentiation and 19 cases of low differentiation. The expression levels of long non-coding RNA (lncRNA) HOTAIR in cancer tissues and adjacent tissues of gastric cancer patients were detected by real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR), andanalyzed the correlation between the expression of HOTAIR and the clinical characteristics of gastric cancer patients. lncRNA HOTAIR small interfering RNA (siRNA) were designed and synthesized, and the silencing model was established in the primary SGC-7901 gastric cancer cell line. The expression of lncRNA HOTAIR in primary SGC-7901 gastric cancer cells was detected, add the effects of lncRNA HOTAIR on the proliferation and apoptosis of cancer cellsanalyzed. The molecular regulatory mechanism was studied by Western blotting and RT-qPCR. Results The expression of lncRNA HOTAIR in cancer tissues was (4.367±0.352), higher than that in adjacent tissues (0.984±0.782) (P 0.05). After 48 h of lncRNA HOTAIR siRNA transfection, the ratio of early apoptotic cells [(22.69±3.21)% vs. (10.97±1.52)%], late apoptotic cells [(30.41±3.97)% vs. (7.40±1.71)%] and necrotic cells [(5.53±0.74)% vs. (3.44±0.42)%] was significantly higher than that of untransfected cells (t=5.715, 9.220, 4.254, P<0.05). The relative expression of Wnt3a protein in the cells after transfection was significantly lower than that in the untransfected group (0.39±0.07 vs. 0.92±0.13, t=6.217, P<0.05). Conclusion lncRNA HOTAIR is up-regulated in gastric cancer, while inhibiting HOTAIR expression can inhibit the activation of Wnt/β-catenin signaling pathway by down-regulating Wnt3a protein expression, thereby promoting the apoptosis of gastric cancer cells. Key words: Long non-coding RNA HOX antisense intergenic RNA; Gastric cancer; Apoptosis

Microarray and RNA in situ hybridization assay for recurrence risk markers of breast carcinoma and ductal carcinoma in situ: Evidence supporting the use of diverse pathways panels.

Breast tumor stratification by recurrence-risk is critical for deciding patient treatment. Here an approach combining cancer pathways microarray data complemented by RNA in situ hybridization (ISH) was investigated as a means for recurrence marker discovery and visualization in pathology specimens. LncRNA and mRNA expressions in breast carcinomas with low (n = 8) vs intermediate/high (n = 10) recurrence-scores as estimated by 21-gene assay and pathology review were compared by microarray assay. Tissue microarrays were prepared from breast carcinomas (n = 20) and ductal carcinoma in situ (DCIS) specimens (n = 84 patients) with known outcomes. Thirteen RNA ISH assays were performed: lncRNAs (BBC3-1, FER3, RAD21-AS1, ZEB1-2) and mRNAs (GLO1, GLTSCR2, TGFB1, TLR2) (implicated by the microarray data); MKI67; a pooled panel of recurrence-associated proliferation markers (BIRC5, Cyclin B1, MKI67, MYBL2, STK15); a pooled panel of non-proliferation recurrence-associated markers (CEACAM5, HTF9C, NDRG1, TP53, SLC7A5); and lncRNAs H19 and HOTAIR. Seven lncRNAs and 10 mRNAs showed significantly (P < .05) altered upregulation or downregulation by microarray assay: carcinoma RNA ISH staining did not mirror these patterns. HOTAIR staining was associated with a higher breast cancer recurrence score (P = .0152); qualitatively, H19 was massively expressed in a metaplastic triple negative breast carcinoma. Among the DCIS cohort, significant associations with multiple outcome variables were noted for TGFB1 and the non-proliferation panel (P-value range: .0001 to .047); proliferation panel staining showed an association with increasing DCIS grade (P = .0269) but not with outcomes. The findings support recurrence-risk estimation by the use of multi-marker panels that are representative of diverse cellular pathways rather than over-reliance on proliferation targets. H19, HOTAIR, and TGFB1 RNA ISH show potential for selective diagnostics.

RETRACTED ARTICLE: Silencing lncRNA HOTAIR declines synovial inflammation and synoviocyte proliferation and promotes synoviocyte apoptosis in osteoarthritis rats by inhibiting Wnt/β-catenin signaling pathway

Statement of Retraction We, the Editors and Publisher of the journal Cell Cycle, have retracted the following article: Tian Mao, Chengjian He, Huafeng Wu, Bo Yang & Xin Li (2019) ‘Silencing lncRNA HOTAIR declines synovial inflammation and synoviocyte proliferation and promotes synoviocyte apoptosis in osteoarthritis rats by inhibiting Wnt/β-catenin signaling pathway’ Cell Cycle, 18:22, https://doi.org/10.1080/15384101.2019.1671716 Since publication, the authors have raised significant concerns about the reliability of the data presented in the article. As the Editor and Publisher also have concerns about the integrity of the reported results, all parties have agreed to retract the article to ensure correction of the scholarly record. We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as ‘Retracted’.

MiR‐200c overexpression inhibits the invasion and tumorigenicity of epithelial ovarian cancer cells by suppressing lncRNA HOTAIR in mice

Epithelial ovarian cancer (EOC) is a common ovarian cancer in gynecological cancers today. It has been found that microRNAs and long-chain noncoding RNA (lncRNA) regulate the gene transcriptional expression in cells. However, it is not well understood that the upstream and downstream regulatory molecules of lncRNA HOX antisense intergenic RNA (HOTAIR). The effects of miR-200c overexpression on the invasion and nude mouse tumorigenicity, as well as lncRNA HOTAIR and snail expression of EOC SKOV3 cells, should be further explored. The expression of miR-200c and lncRNA HOTAIR was detected by reverse transcription PCR (RT-PCR) in EOC SKOV3 cells. The whole miR-200c gene fragment was cloned into a lentiviral plasmid vector. The miR-200c expression in transducted SKOV3 cells with reconstructed miR-200c lentivirus was significantly higher than the negative control (P < .01). The lentivirus-miR-200c-SKOV3 cells show that the invasion ability was significantly decreased compared with the negative control (P < .01). The nude mouse tumorigenicity was significantly decreased compared with that of the control group (P < .01). The snail protein expression in lentivirus-miR-200c-SKOV3 xenograft tumor was significantly decreased compared with the negative control lentivirus-SKOV3 group (P < .05). The miR-200c overexpression significantly decreased the expressions of lncRNA HOTAIR and snail, but increased E-cadherin expression in the lentivirus-miR-200c transducted SKOV3 cells of xenograft tumor, compared with the negative control (P < .05). The miR-200c overexpression in SKOV3 cells with transducted lentivirus-miR-200c can inhibit lncRNA HOTAIR expression, decrease snail, increase E-cadherin and significantly reduce the invasion and tumorigenicity of EOC SKOV3 cells. These results suggest that the miR-200c and lncRNA HOTAIR could be effective therapeutic targets for human epithelial ovarian cancer treatment.

LncRNA HOTAIR promotes gastric cancer proliferation and metastasis via targeting miR-126 to active CXCR4 and RhoA signaling pathway.

HOTAIR, a well‐known long noncoding RNAs (lncRNA), has been recognized to contribute to the tumor metastasis in several tumors. But its role in gastric cancer remains elusive. Here, we reported an increase in HOTAIR promoted proliferation and metastasis of gastric cancer cell lines. The HOTAIR and miR‐126 level was determined in 15 paired primary gastric cancer tissues and their adjacent noncancerous gastric tissues. Over‐expression or downregulation HOTAIR was conducted in AGS or BGC‐823 cells to investigate the impact of HOTAIR in proliferation and metastasis. Then dual luciferase reporter assay was utilized to study the interaction between CXCR4 and miR‐126. Cells transfected with shHOTAIR or miR‐126 mimic were subjected to western blot to investigate the role of SDF‐1/CXCR4 signaling in HOTAIR mediated proliferation and metastasis. HOTAIR was highly expressed in gastric cancer tissues and several gastric cancer cell lines. Overexpressed HOTAIR facilitated proliferation and metastasis in vitro while HOTAIR knockdown inhibit proliferation and metastasis. A negative correlation was observed between miR‐126 and HOTAIR. And, we also confirmed the decrease in miR‐126 in clinic specimen. Furthermore, HOTAIR and miR‐126 negatively regulated each other and then increase or decrease CXCR4 expression and downstream pathway, respectively. CXCR4 was confirmed as a direct target of miR‐126. Our study demonstrated that high HOTAIR expression promote proliferation and metastasis in gastric cancer via miR‐126/CXCR4 axis and downstream signaling pathways.

Long non-coding RNA HOTAIR modulates intervertebral disc degenerative changes via Wnt/\u03b2-catenin pathway

BackgroundIntervertebral disc degeneration (IDD) has a complicated and enigmatic pathogenic process. Accumulating evidence shows that long non-coding RNAs (LncRNAs) play a role in the pathogenesis of IDD. This study aimed to investigate the expression and role of the LncRNA HOTAIR in IDD pathogenesis.MethodsNucleus pulposus (NP) tissue samples from 10 patients with idiopathic scoliosis and 10 patients with lumbar disc herniation were collected. qRT-PCR was used to assess the expression of HOTAIR and ECM-related genes; western blotting was used to detect the expression of senescence biomarkers, apoptosis-related proteins, and Wnt/β-catenin pathway; flow cytometry was used to detect apoptosis; and the MTT assay was used to determine cell proliferation. Moreover, a classic needle-punctured rat tail model was used to investigate the role of HOTAIR in IDD in vivo.ResultsThe results showed that the expression of HOTAIR significantly increased during IDD progression. The overexpression of HOTAIR was found to induce nucleus pulposus (NP) cell senescence, apoptosis, and extracellular matrix (ECM) degradation. HOTAIR silencing by RNA interference in NP cells prevented interleukin-1β-induced NP cell senescence, apoptosis, and ECM degradation. Furthermore, we found that the Wnt/β-catenin pathway played a role in regulating HOTAIR to induce these changes in NP cells. Moreover, HOTAIR inhibition in a rat model effectively attenuated IDD symptoms in vivo.ConclusionsOur findings confirmed that HOTAIR promoted NP cell senescence, apoptosis, and ECM degradation via the activation of the Wnt/β-catenin pathway, while silencing HOTAIR attenuated this degeneration process, indicating a potential therapeutic target against IDD.

LncRNA HOTAIR upregulates autophagy to promote apoptosis and senescence of nucleus pulposus cells.

Intervertebral disc degeneration (IDD) is a complex and chronic disease that involves disc cell senescence, death, and extracellular matrix (ECM) degradation. HOTAIR, a long non-coding RNA (lncRNA) is reportedly associated with autophagy, whereas autophagy is shown to promote IDD. However, how it affects nucleus pulposus (NP) cells, the primary component of intervertebral discs is still unclear. We hypothesized that HOTAIR promotes NP cell apoptosis and senescence through upregulating autophagy. Thus, silencing HOTAIR should inhibit autophagy and exert a therapeutic effect on IDD. Our in vitro experiments in human NP cells revealed that HOTAIR expression positively correlated with IDD grade, and overexpression enhanced autophagy. Autophagy inhibition via 3-methyladenine reversed HOTAIR stimulatory effects on apoptosis, senescence, and ECM catabolism, while the AMP-activated protein kinase (AMPK) inhibitor Compound C suppressed HOTAIR-induced autophagy through regulating AMPK/mTOR/ULK1 pathways. Our in vivo experiment then illustrated that silencing HOTAIR ameliorates IDD in rats. Collectively, we demonstrated that HOTAIR stimulates autophagy to promote NP cell apoptosis, senescence, and ECM catabolism. Therefore, silencing HOTAIR has the potential to become a treatment option for IDD.