lncRNA Differentiation Antagonizing Non-protein Coding RNA Research Articles

Spotlight on the Expanding Role of DANCR in Tumorigenesis and Tumor Progression

Context: Long non-coding RNA (lncRNA) is a novel set of non-coding RNAs (ncRNA), over 200 nucleotides in length, accounting for the regulation of genes and chromosome structure. There are a few articles, mostly focusing on changes in the expression profile of DANCR. However, this review tried to collect documents to discuss the molecular mechanisms of this lncRNA in different cellular signaling pathways, considering microRNAs, to obtain a better understanding of its mode of action. Evidence Acquisition: Differentiation antagonizing non-protein coding RNA (DANCR) is a cancer-associated lncRNA whose dysregulation, mostly upregulation, has been reported in almost all cancers, particularly in stages of invasion, migration, and progression. The regulatory mechanism of DANCR is mostly working as competitive endogenous RNAs (ceRNAs), leading to the hypothesis that lncRNA DANCR has oncogenic functions in malignancies. LncRNA DANCR harbors a number of MicroRNA Response Elements (MREs) for various microRNAs involved in different pathways, which are responsible for turning the situation toward supremacy for the dissemination of cancerous cells and ultimately metastasis, such as PI3K/Akt, TGF-β, Wnt, JAK-STAT, EMT, and DNA damages. In fact, lncRNA DANCR could potentially sequester microRNAs from their targeted mRNAs, which share the same MREs as DANCR. Conclusion: This review article provides proper evidence, of why the aberrant expression of DANCR pathophysiologically turns the circumstances toward supremacy for the progression, migration, and invasion of cancerous cells, and proposes this lncRNA as a potent and extremely promising prognostic marker for the early detection of tumor progression and metastasis, as well as a therapeutic target for controlling the progression of several human malignancies.

LncRNA DANCR restrained the survival of mycobacterium tuberculosis H37Ra by sponging miR-1301-3p/miR-5194.

Tuberculosis is a worldwide contagion caused by Mycobacterium tuberculosis (MTB). MTB is characterized by intracellular parasitism and is semi-dormant inside host cells. The persistent inflammation caused by MTB can form a granuloma in lesion regions and intensify the latency of bacteria. In recent years, several studies have proven that long non-coding RNAs (lncRNAs) play critical roles in modulating autophagy. In our study, the Gene Expression Omnibus (GEO) databases were searched for lncRNAs that are associated with tuberculosis. We found that lncRNA differentiation antagonizing non-protein coding RNA (DANCR) increased in the peripheral blood samples collected from 54 pulmonary tuberculosis patients compared to 23 healthy donors. By constructing DANCR overexpression cells, we analyzed the possible cellular function of DANCR. After analyzing our experiments, it was found that the data revealed that upregulation of DANCR facilitated the expression of signal transducer and activator of transcription 3, autophagy-related 4D cysteine peptides, autophagy-related 5, Ras homolog enriched in the brain, and microtubule-associated protein 1A/1B light chain 3 (STAT3, ATG4D, ATG5, RHEB, and LC3, respectively) by sponging miR-1301-3p and miR-5194. Immunofluorescence analysis indicated that DANCR played a positive role in both autophagosome formation and fusion of autolysosomes in macrophages. The colony-forming unit (CFU) assay data also showed that the cells overexpressing DANCR were more efficient in eliminating the intracellular H37Ra strain. Consequently, these data suggest that DANCR restrained intracellular survival of M. tuberculosis by promoting autophagy via miR-1301-3p and miR-5194.

Exploring the Temporal Correlation of Sarcopenia with Bone Mineral Density and the Effects of Osteoblast-Derived Exosomes on Myoblasts through an Oxidative Stress-Related Gene.

Sarcopenia is an age-related accelerated loss of muscle strength and mass. Bone and muscle are closely related as they are physically adjacent, and bone can influence muscle. However, the temporal association between bone mineral density (BMD) and muscle mass in different regions of the body after adjustment for potential indicators and the mechanisms by which bone influences muscle in sarcopenia remain unclear. Therefore, this study aimed to explore the temporal association between muscle mass and BMD in different regions of the body and mechanisms by which bone regulates muscle in sarcopenia. Here, cross-lagged models were utilized to analyze the temporal association between BMD and muscle mass. We found that low-density lipoprotein (LDL-C) positively predicted appendicular lean mass. Mean whole-body BMD (WBTOT BMD), lumbar spine BMD (LS BMD), and pelvic BMD (PELV BMD) temporally and positively predicted appendicular lean mass, and appendicular lean mass temporally and positively predicted WBTOT BMD, LS BMD, and PELV BMD. Moreover, this study revealed that primary mice femur osteoblasts, but not primary mice skull osteoblasts, induced differentiation of C2C12 myoblasts through exosomes. Furthermore, the level of long noncoding RNA (lncRNA) taurine upregulated 1 (TUG1) was decreased, and the level of lncRNA differentiation antagonizing nonprotein coding RNA (DANCR) was increased in skull osteoblast–derived exosomes, the opposite of femur osteoblast–secreted exosomes. In addition, lncRNA TUG1 enhanced and lncRNA DANCR suppressed the differentiation of myoblasts through regulating the transcription of oxidative stress–related myogenin (Myog) gene by modifying the binding of myogenic factor 5 (Myf5) to the Myog gene promoter via affecting the nuclear translocation of Myf5. The results of the present study may provide novel diagnostic biomarkers and therapeutic targets for sarcopenia.

The lncRNA DANCR promotes development of atherosclerosis by regulating the miR-214-5p/COX20 signaling pathway

BackgroundAlthough long non-coding RNA differentiation antagonizing non-protein coding RNA (DANCR) has been reported to be involved in atherosclerosis (AS) development, its specific mechanism remains unclear.MethodsDANCR expression levels in blood samples of AS patients and oxidized low-density lipoprotein (ox-LDL) treated vascular smooth muscle cells (VSMCs) and human umbilical vein endothelial cells (HUVECs) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The small interfering RNA targeting DANCR (si-DANCR) was used to silence DANCR expression. Cell viability was assessed by CCK-8 assay. Cell apoptosis was evaluated by flow cytometry. Levels of inflammatory cytokines, anti-oxidative enzyme superoxide dismutase (SOD) activity, and malonaldehyde (MDA) were detected by specific commercial kits. An animal AS model was established to confirm the role of DANCR/microR-214-5p/COX20 (the chaperone of cytochrome c oxidase subunit II COX2) in AS development.ResultsDANCR was significantly increased in the blood samples of AS patients and ox-LDL treated VSMCs and HUVECs. DANCR downregulation obviously increased viability and reduced apoptosis of ox-LDL-treated VSMCs and HUVECs. Meanwhile, DANCR downregulation reduced the levels of inflammatory cytokines, including interleukin (IL)-6 (IL-6), IL-1beta (IL-1β), IL-6 and tumor necrosis factor (TNF)-alpha (TNF-α) and MDA while increasing the SOD level in ox-LDL-treated VSMCs and HUVECs. DANCR regulated COX20 expression by acting as a competing endogenous RNA (ceRNA) of miR-214-5p. Rescue experiments demonstrated that miR-214-5p downregulation obviously attenuated si-DANCR-induced protective effects on ox-LDL-caused endothelial injury.ConclusionsOur results revealed that DANCR promoted AS progression by targeting the miR-214-5p/COX20 axis, suggesting that DANCR might be a potential therapeutic target for AS.

High serum exosomal long non-coding RNA DANCR expression confers poor prognosis in patients with breast cancer.

BackgroundExosomal long non‐coding RNAs (lncRNAs) serve as excellent candidate biomarkers for clinical applications. The expression of differentiation antagonizing non‐protein coding RNA (DANCR) has been shown to be decreased in breast cancer (BC) tissues and cell lines. However, the clinical value of circulating exosomal DANCR in BC has not been explored.MethodsA total of 120 BC patients, 70 benign breast disease (BBD) patients, and 105 healthy women were recruited in this study. Total RNA was extracted from serum samples, and the level of serum exosomal lncRNA DANCR was evaluated by quantitative real‐time reverse transcription‐polymerase chain reaction (qRT‐PCR).ResultsSerum exosomal lncRNA DANCR levels were significantly higher in BC patients than in BBD patients and normal controls. The diagnostic performance of serum exosomal lncRNA DANCR was good, and the combination of serum exosomal lncRNA DANCR, CA153, and CEA greatly improved the diagnostic accuracy for BC. High serum exosomal lncRNA DANCR level was associated with various clinicopathological variables including lymph node metastasis, ER status, HER2 status, and TNM stage. In addition, the BC patients in the high serum exosomal lncRNA DANCR expression group had significantly shorter 5‐year overall survival time. Multivariate analysis demonstrated that serum exosomal lncRNA DANCR was an independent risk factor for BC.ConclusionSerum exosomal lncRNA DANCR may be a useful non‐invasive biomarker for the clinical diagnosis and prognosis of BC.

Exosomes Secreted by Mesenchymal Stem Cells Induce Immune Tolerance to Mouse Kidney Transplantation via Transporting LncRNA DANCR.

Mesenchymal stem cells induce kidney transplant tolerance by increasing regulatory T (Treg) cells. Bone marrow mesenchymal stem cell exosomes (BMMSC-Ex) promote Treg cell differentiation. Long non-coding RNA differentiation antagonizing non-protein coding RNA (DANCR) is expressed in BMMSCs and can be encapsulated in exosomes. We aimed to explore the role of DANCR in BMMSC-Ex in immune tolerance after kidney transplantation and related mechanism. The isogenic/allograft kidney transplantation mouse model was established, and levels of serum creatinine (SCr) were determined. Hematoxylin-eosin staining was conducted to detect the inflammation, and immunohistochemistry was performed to detect the infiltration of CD4+ T cells. Levels of IFN-γ, IL-17, and IL-2 were examined by ELISA. Flow cytometry was conducted to determine Treg cells. In the allograft group, the inflammatory response was severe, CD4+ T cell infiltration, SCr levels, and plasma rejection-related factors were up-regulated, while injection of BMMSC-Ex reversed the results. BMMSC-Ex increased Treg cells in kidney transplantation mice. Interference with DANCR reversed the promoting effect of BMMSC-Ex on Treg cell differentiation. DANCR bound to SIRT1, promoted ubiquitination and accelerated its degradation. The injection of BMMSC-Ex (after interference with DANCR) promoted SIRT1 levels, inflammatory response, CD4+ T cell infiltration, SCr levels, and plasma rejection related factors' expression, while Treg cells were decreased. LncRNA DANCR in BMMSC-Ex promoted Treg cell differentiation and induced immune tolerance of kidney transplantation by down-regulating SIRT1 expression in CD4+ T cells.

Inhibition of the lncRNA DANCR attenuates cardiomyocyte injury induced by oxygen-glucose deprivation via the miR-19a-3p/MAPK1 axis.

Long noncoding RNAs (lncRNAs) have been considered as crucial regulators of acute myocardial infarction (AMI). In this study, to analyze the effect of differentiation antagonizing nonprotein coding RNA (DANCR) of lncRNA on cardiomyocyte damage in AMI, cardiomyocyte injury was induced by oxygen-glucose deprivation (OGD). Cell counting kit-8 (CCK-8) assay and flow cytometry were used to assess cell viability and apoptosis, respectively. Quantitative real-time PCR was used to measure the expression levels of DANCR and miR-19a-3p. Bioinformatics analysis and luciferase gene reporter assay were utilized to explore the relationship among DANCR, miR-19a-3p, and mitogen-activated protein kinase 1 (MAPK1). CCK-8 and TUNEL assays were used to explore the effects of DANCR alone or plus miR-19a-3p on the viability and apoptosis of OGD/R-exposed HL-1 cells. Western blot analysis was used to detect changes in the MAPK1/ERK1/2 pathway in HL-1 cells. We found that DANCR expression and miR-19a-3p level are negatively correlated as DANCR expression is increased, while miR-19a-3p level is decreased in AMI patients' serum and OGD/R-exposed HL-1 cells. DANCR knockdown increased miR-19a-3p level, and miR-19a-3p inhibition increased DANCR expression. Moreover, DANCR directly binds to miR-19a-3p. DANCR knockdown reduced viability but induced apoptosis in OGD/R-exposed HL-1 cells, while miR-19a-3p inhibition weakens these effects. Furthermore, MAPK1 is a target of miR-19a-3p. miR-19a-3p overexpression decreases MAPK1 and ERK1/2 in HL-1 cells, while miR-19a-3p inhibition increases MAPK1 and ERK1/2 in HL-1 cells. Moreover, DANCR knockdown reduces myocardium apoptosis in mice with the left anterior descending artery ligated. DANCR knockdown effectively restores myocardial cell apoptosis by regulating the miR-19a-3p/MAPK1/ERK1/2 axis.

Long non‑coding RNA DANCR represses the viability, migration and invasion of multiple myeloma cells by sponging miR‑135b‑5p to target KLF9.

Multiple myeloma (MM) is a malignancy of plasma cells that leads to marrow failure and bone lesions. Numerous studies have verified the link between long non‑coding RNAs (lncRNAs) and MM. The present study aimed to examine the role and underlying mechanism of differentiation antagonizing non‑protein coding RNA (DANCR) in MM cells. The relative expression levels of DANCR, microRNA (miR)‑135b‑5p and Krüppel‑like factor 9 (KLF9) were examined using reverse transcription‑quantitative PCR. Cell viability was assessed using the MTT assay, while relative cell migration and invasion were evaluated using Transwell assays. Moreover, the dual‑luciferase reporter assay was used to examine the interplay between DANCR, miR‑135b‑5p and KLF9. Western blotting was performed to determine the expression level of KLF9. It was found that lncRNA DANCR and KLF9 were downregulated, while miR‑135b‑5p was upregulated in the serum of patients with MM and in MM cells compared with the controls. Overexpressing DANCR or knocking down miR‑135b‑5p reduced the viability of the MM cells, as well as restrained MM cells from migrating and invading. Furthermore, DANCR directly targeted miR‑135b‑5p and was negatively correlated with miR‑135b‑5p. It was also found that KLF9 was targeted by miR‑135b‑5p and was inversely correlated with miR‑135b‑5p expression. The impact of lncRNA DANCR‑mediated suppression on cell viability, invasion and migration was partially abolished by short hairpin RNA KLF9 or miR‑135b‑5p mimics transfection in MM cells. Thus, it was suggested that lncRNA DANCR repressed the viability, migration and invasion of MM cells by sponging miR‑135b‑5p to target KLF9.

LncRNA DANCR improves the dysfunction of the intestinal barrier and alleviates epithelial injury by targeting the miR-1306-5p/PLK1 axis in sepsis.

Intestinal barrier dysfunction often occurs in various acute or chronic pathological conditions and has been identified as an important clinical problem. Herein, we explored the biological role and molecular mechanism of Polo-like kinase 1 (PLK1) and differentiation antagonizing non-protein coding RNA (DANCR) in intestinal barrier dysfunction caused by sepsis. RT-qPCR analysis was used to examine PLK1, miR-1306-5p, and DANCR expression in NCM460 cells after LPS treatment. TUNEL assay and Western blot analysis were performed to explore PLK1 function in cell apoptosis and intestinal barrier in vitro. Hematoxylin and eosin staining, Western blot analysis, and TUNEL assay were used to investigate DANCR function in the intestinal barrier and cell apoptosis in vivo. The interaction between miR-1306-5p and PLK1 (or DANCR) was validated by luciferase reporter assay. As a result, PLK1 overexpression decreased cell apoptosis and promoted intestinal barrier function. Moreover, DANCR was validated as a sponge of miR-1306-5p to target PLK1. In addition, we found that DANCR overexpression decreased intestinal mucosal permeability and colon mucosa epithelial cell apoptosis in vivo. Conclusively, DANCR improved intestinal barrier dysfunction and alleviated epithelial injury by targeting the miR-1306-5p/PLK1 axis in sepsis.

Emerging role of lncRNA DANCR in progenitor cells: beyond cancer.

Long noncoding RNAs (lncRNAs) are important participants in biological processes including cell proliferation, differentiation and death, as well as pathogenesis of various diseases. LncRNA differentiation antagonizing non-protein coding RNA (DANCR) is an emerging regulator in cell metabolism and many diseases besides cancers. DANCR is negative in epidermal, osteoblastic and endoderm differentiation, but positive in chondrogenic differentiation of progenitor cells. It is protective for calcification of the ligamentum flavum, stroke, acute myocardial infarction and arterial calcification, but a risk factor for bone loss, fracture healing and idiopathic pulmonary fibrosis. In addition, DANCR is a potential target for improving tissue regeneration. Mechanically, DANCR, a cytoplasmic lncRNA, sponges corresponding microRNAs or interacts with various proteins. This review aims to summarize the role of DANCR in progenitor cells and provide perspectives for further studies.

LncRNA DANCR promotes ATG7 expression to accelerate hepatocellular carcinoma cell proliferation and autophagy by sponging miR-222-3p.

LncRNA differentiation antagonizing non-protein coding RNA (DANCR) is an oncogene in various malignant cancers, including hepatocellular carcinoma (HCC). Autophagy is an intracellular self-digestion mechanism that accelerates the progression of HCC via promoting cell survival. However, the role of lncRNA DANCR in HCC, and the mechanism of lncRNA DANCR in the regulation of autophagy in HCC remains unknown. Therefore, the aims of this study are the investigation of the role of lncRNA DANCR in HCC, and the exploration of the molecular mechanism of lncRNA DANCR in regulating autophagy of HCC cells. In this study, the expression of lncRNA DANCR, miR-222-3p, and autophagy-related gene 7 (ATG7) was detected by qRT-PCR. The cell proliferation and colony formation were measured by Cell Counting Kit-8 (CCK-8) assay and colony formation assay. And the autophagic flux was evaluated by mRFP-GFP-LC3B reporter. The autophagy related proteins were analyzed by Western blotting. Besides, the relationship between lncRNA DANCR and miR-222-3p, as well as between miR-222-3p and ATG7, was determined by Dual-Luciferase reporter system. We found high expression of lncRNA DANCR and ATG7, and low expression of miR-222-3p in HCC tissues and cell lines. And lncRNA DANCR positively correlated with poor survival of HCC patients. Moreover, the knockdown of lncRNA DANCR inhibited cell proliferation and autophagy of HCC cells. And we predicted and proved that lncRNA DANCR induced cell proliferation, colony formation and autophagy by increasing ATG7 and suppressing miR-222-3p. Our study demonstrates the promoting role of lncRNA DANCR in HCC, and indicates the regulatory effects of lncRNA DANCR on regulating autophagy of HCC.

LncRNA DANCR Promotes Proliferation and Metastasis of Breast Cancer Cells Through Sponging miR-4319 and Upregulating VAPB.

Background: Breast cancer is one of the most prevalent cancers that often occur in females. Long noncoding RNA differentiation antagonizing nonprotein coding RNA (DANCR) has been involved in the pathogenesis of various tumors, including breast cancer. This study aimed to investigate the role and underlying mechanism of DANCR in breast cancer. Materials and Methods: The level of DANCR was detected in breast cancer tissues and cells by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability was evaluated by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Cell apoptosis was assessed using flow cytometry. Cell migration and invasion were estimated by the Transwell assay. The relationship between DANCR, miR-4319, and vesicle-associated membrane protein-associated protein B (VAPB) was confirmed by bioinformatic analysis and dual-luciferase reporter assay. The level of microRNA-4319 (miR-4319) was tested by qRT-PCR. The expression of VAPB was measured by qRT-PCR or Western blot assay. Results: DANCR and VAPB were upregulated, while miR-4319 was downregulated in breast cancer tissues and cells. Knockdown of DANCR hindered proliferation, migration, and invasion and promoted apoptosis of breast cancer cells. DANCR knockdown inhibited breast cancer development through regulating miR-4319. Inhibition of miR-4319 restrained breast cancer cell progression by targeting VAPB. Moreover, DANCR regulated VAPB expression by sponging miR-4319 in breast cancer cells. Conclusion: DANCR facilitated breast cancer cell progression through regulating the miR-4319/VAPB axis, indicating that DANCR might be a potential biomarker and therapeutic target for breast cancer treatment.

Exosome-Derived Differentiation Antagonizing Non-Protein Coding RNA Promotes Tumor Recurrences in Hepatitis C-Related Hepatocellular Carcinoma

Background & Aims: Differentiation antagonizing non-protein coding RNA (DANCR) associated with various types of neoplasms. Hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) (HCV-HCC) has a high risk of recurrence. We explored the role of DANCR in HCV-related hepatocarcinogenesis and identified potential therapeutic targets and non-invasive prognostic markers for long-term outcome of HCV-HCC after surgical resection. Methods: DANCR relevant to HCV-HCC were identified by comparative RNA-sequencing of tumor (T) and adjacent non-tumor (ANT) tissues in a screening set, validated using real-time PCR Target lncRNAs in tissues and serum exosomes were used to predict HCC recurrence of HCV-HCC after curative surgical resection in a large application cohort. Exosome-Derived DANCR was explored using JFH1-infected cells and macrophages. Results: We confirmed that DANCR was upregulated by HCV infection and identified as the lncRNA most relevant to HCV-HCC in tumor as compared to ANT tissues. In 183 HCV-HCC patients followed for 10 years after curative HCC resection, the expression level of circulating exosomal DANCR was positively associated with HCC recurrence and was the most predictive factor associated with HCC recurrence and mortality (hazard ratio/95% confidence intervals: 7.0/4.3–11.6 and 2.7/1.5–5.1, respectively). In vitro study further demonstrated that exosomal DANCR was positively associated with mesenchymal-associated β-catenin expression in HCV infectious hepatocyte and macrophages, which might consequently promote tumor cell migration and invasion abilities in the tumor microenvironment. Conclusions: The lncRNA DANCR is highly relevant to disease progression of HCV-HCC Furthermore, circulating exosomal DANCR might serve as a non-invasive prognostic biomarker for HCV-HCC. Funding Statement: This study supported by the grants from the Ministry of Science Technology (MOST) grant (108-2314-B-037-079-MY3) (106-2221-E-039-011-MY3); China medical University (CMU108-MF-93), (CMU108-Z-02), (CMU108-S-22); Kaohsiung Medical University (KMU-Q108009), (KMUQ109005), (108-CCH-KMU-001); partially by Kaohsiung Medical University Research Grant KMU-TC108A04 and KMU-TC108B06. This study was partially supported by of Liquid Biopsy and of Cancer Research, Kaohsiung Medical University, and the Center for Intelligent Drug Systems and Smart Bio-devices (IDS2B) from The Featured Areas Research Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE) in Taiwan. Declaration of Interests: All authors declare no support from any organization other than the below mentioned ones for the submitted work; no financial relationships with any organizations that might have an interest in the submitted work in the previous 3 years; and no other relationships or activities that could appear to have influenced the submitted work. Hence, all authors declare themselves to be independent from funders with respect to this manuscript. Ethics Approval Statement: The study protocol was approved by the Institutional Review Board at each hospital and the TLCN User Committee and was carried out in accordance with the Declaration of Helsinki and the guidelines of the International Conference on Harmonization for Good Clinical Practice.

Circulating lncRNA DANCR as a potential auxillary biomarker for the diagnosis and prognostic prediction of colorectal cancer

Studies have shown that long non-coding RNAs (lncRNAs) play vital roles in the development of cancer, including colorectal cancer (CRC). Our purpose is to validate the diagnostic value of serum differentiation antagonizing non-protein coding RNA (DANCR) in CRC by focusing on its expression and clinical application. lncRNA expression profiles of CRC patients were obtained and analyzed by repurposing the publically available microarray data. Tissue or serum specimens were obtained from 40 patients with primary CRC, 10 patients with recurrent CRC, 40 patients with colorectal polyps, and 40 healthy controls. It was found that DANCR level in the CRC tissue and serum was significantly increased, and serum DANCR expression was decreased in post-operative patients as compared with that in pre-treatment patients and recurrent patients. In addition, serum DANCR expression was significantly correlated with different TNM stages. Correlation analysis of DANCR and other diagnostic indicators showed that the serum DANCR expression level was significantly correlated with CA199 but not with CEA in CRC patients. As for diagnostic efficiency by ROC analysis, the area under the curve (AUC) of serum DANCR was higher than that of CEA and CA199 in CRC group vs. colorectal polyp group. Simultaneous detection of DANCR, CEA and CA199 yielded the highest sensitivity and AUC as compared with either of them alone. Taken together, serum DANCR was up-regulated in CRC patients and high expression of DANCR may prove to be a potential biomarker for the diagnosis of CRC.

LncRNA DANCR Promotes Sorafenib Resistance via Activation of IL-6/STAT3 Signaling in Hepatocellular Carcinoma Cells.

BackgroundHepatocellular carcinoma (HCC) is one of the major malignancies and the second most common cause of cancer-related death worldwide. Sorafenib, an approved first-line systematic treatment agent for HCC, is capable to effectively improve the survival of patients with advanced HCC. The long-noncoding RNA (lncRNA) differentiation antagonizing non-protein coding RNA (DANCR) has been reported to exert oncogenic functions in several kinds of human cancers. However, the role of lncRNA DANCR in sorafenib resistance in HCC remains unknown.MethodsThe expression levels of DANCR in HCC tissues were detected by qRT-PCR. DANCR overexpression and knockdown models were established and utilized to investigate the functional role of DANCR on sorafenib resistance in HCC cells. The MS2-binding sequences-MS2-binding protein–based RNA immunoprecipitation assay, RNA pull-down and luciferase reporter assay was used to detect the association between DANCR and PSMD10 mRNA. The activation of DANCR transcription mediated by STAT3 was assessed by luciferase reporter and chromatin immunoprecipitation assays.ResultsWe found that DANCR was significantly overexpressed in HCC tissues and associated with prognosis of HCC patients. Overexpression and knockdown experiments demonstrated that DANCR promoted sorafenib resistance in HCC cells in vitro and in vivo. Mechanistically, the role of DANCR relied largely on the association with PSMD10. DANCR stabilized PSMD10 mRNA through blocking the repressing effect of several microRNAs on PSMD10. Besides, DANCR activated IL-6/STAT3 signaling via PSMD10. Furthermore, we revealed that DANCR transcription was enhanced by the activation of IL-6/STAT3 signaling, indicating a positive feedback loop of DANCR and IL-6/STAT3 signaling.ConclusionCollectively, our study is the first to elucidate the mechanism of DANCR-mediated sorafenib resistance via PSMD10-IL-6/STAT3 signaling axis, which provides a promising target for developing new therapeutic strategy for sorafenib tolerance of HCC.

LncRNA DANCR attenuates brain microvascular endothelial cell damage induced by oxygen-glucose deprivation through regulating of miR-33a-5p/XBP1s

Brain microvascular endothelial cell (BMEC) survival and angiogenesis after ischemic stroke has great significance for improving the prognosis of stroke. Abnormal variants of lncRNAs are closely associated with stroke. In this study, we examined the effects and molecular mechanisms of differentiation antagonizing non-protein coding RNA (DANCR) on apoptosis, migration, and angiogenesis of oxygen-glucose deprivation (OGD)-treated BMECs. We found that DANCR expression significantly increased at 2, 4, 6, 8, and 10 h after OGD. DANCR overexpression promoted cell viability, migration, and angiogenesis in OGD-treated BMECs. Additionally, we found that X-box binding protein l splicing (XBP1s) expression was positively correlated with DANCR expression. DANCR overexpression promoted XBP1s expression in OGD-treated BMECs. Silenced XBP1s reversed the effect of DANCR in OGD-treated BMECs. Furthermore, we found that microRNA (miR)-33a-5p bound to DANCR and the 3'-UTR of XBP1. miR-33a-5p overexpression inhibited proliferation, migration, angiogenesis, and XBP1s expression in OGD-treated DANCR-overexpressing BMECs, reversing the protective effect of DANCR. Finally, we found that XBP1s expression promoted proliferation, migration, and angiogenesis, reversing the damaging effect of miR-33a-5p. In conclusion, DANCR enhanced survival and angiogenesis in OGD-treated BMECs through the miR-33a-5p/XBP1s axis.

Angelica Sinensis Polysaccharide Suppresses Epithelial-Mesenchymal Transition and Pulmonary Fibrosis via a DANCR/AUF-1/FOXO3 Regulatory Axis.

Idiopathic pulmonary fibrosis (IPF) is characterized by the accumulation of lung fibroblasts and extracellular matrix deposition. Angelica sinensis polysaccharide (ASP), the major bioactive component that can extracted from roots of angelica, plays functional roles in immunomodulation, anti-tumor activity, and hematopoiesis. Emerging evidence has suggested that long noncoding RNAs (lncRNAs) play important roles in pathophysiological processes in various diseases. However, the roles of lncRNAs and ASP in IPF remain poorly understood. In the present study, we investigated the effects of ASP in IPF, as well as their functional interactions with lncRNA DANCR (differentiation antagonizing non-protein coding RNA). IPF models were established by treating Sprague-Dawley rats with BLM and treating alveolar type Ⅱ epithelial (RLE-6TN) cells with TGF-β1. Our results showed that ASP treatment suppressed pulmonary fibrosis in rats and fibrogenesis in RLE-6TN cells. The lncRNA DANCR is downregulated after ASP treatment in both rat lung tissues and RLE-6TN cells, and DANCR overexpression dramatically reversed the suppressive effects of ASP in IPF. Mechanistically, DANCR directly binds with AUF1 (AU-binding factor 1), thereby upregulating FOXO3 mRNA and protein levels. Moreover, overexpression of AUF1 or FOXO3 reversed the functional effects induced by ASP treatment. In conclusion, our findings showed that DANCR mediates ASP-induced suppression of IPF via upregulation of FOXO3 protein levels in an AUF1-dependent manner. Therefore, DANCR could serve as a promising therapeutic target in IPF treatment with ASP.

RETRACTED: LncRNA DANCR silence inhibits SOX5-medicated progression and autophagy in osteosarcoma via regulating miR-216a-5p

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Authors and Editor-in-Chief. The authors of this article have informed the editors that the human anti-LC3 antibody used in this work recognized multiple antigens in murine tissues, leading them to believe that the antibody is contaminated. This possible contamination further leads them to determine that the data generated using these antibodies, and any conclusions based on that data, cannot be considered accurate. Furthermore, the authors also report that subsequent work has revealed that the DANCR/miR-216a-5p axis plays a role in the regulation of beta-oxidation and downstream non-programmed cell death and homeostasis. They therefore have requested to retract this article as unreliable. The authors have not provided the relevant raw data for the editors' review, or the subsequent reported role of DANCR in beta-oxidation. Therefore, given the authors' loss of confidence in these findings, the Editor-in-Chief supports the decision to retract the article.

LncRNA DANCR promotes tumor growth and angiogenesis in ovarian cancer through direct targeting of miR-145.

Differentiation antagonizing non-protein coding RNA (DANCR) is a newly identified oncogenic long noncoding RNA found in various cancers. However, the functional role of DANCR in tumor angiogenesis and the underlying mechanisms are still unclear. The expression of DANCR was determined in ovarian malignant tissues and cell lines. The functional role of DANCR in tumor angiogenesis was revealed by the following methods: CD31 staining of ovarian tumor tissues, matrigel-plug assay tissues, HUVEC-related tube formation assay, and invasion assay. Enzyme-linked immunosorbent assay, Western blotting, luciferase assay, and rescue experiments were used to investigate the underlying mechanisms of DANCR-regulating angiogenesis. DANCR was upregulated in ovarian malignant tissues and ovarian cancer cells. Knockdown of DANCR efficiently impaired ovarian tumor growth through inhibition of tumor angiogenesis. Furthermore, the conditional culture medium from DANCR-knockdown ovarian cells significantly inhibited tube formation and invasion of HUVEC in vitro. Mechanistic investigation indicated that vascular endothelial growth factor A (VEGF-A, VEGF) plays a crucial role during DANCR inhibition of tumor angiogenesis in ovarian cancer. Further results demonstrated that miR-145 is the direct binding target of DANCR during regulation of VEGF expression and tumor angiogenesis in ovarian cancer cells. Collectively, DANCR plays a promotional role in tumor angiogenesis in ovarian cancer through regulation of miR-145/VEGF axis. Therefore, DANCR may be a novel therapy target for ovarian cancer.

MicroRNA-33a-5p suppresses esophageal squamous cell carcinoma progression via regulation of lncRNA DANCR and ZEB1

Increasing evidence displays that microRNAs (miRNAs) participate in the development of various human malignancies, including esophageal squamous cell carcinoma (ESCC). MicroRNA-33a-5p (miR-33a-5p) has recently been reported to function as a tumor suppressor in many human cancers. However, the expression and role of miR-33a-5p in ESCC remains largely unknown. Herein, we discovered that miR-33a-5p was down-regulated in both ESCC tissues and cell lines, compared with their normal counterparts, and decreased expression of miR-33a-5p was found to be closely associated with poor patient prognosis of ESCC. Moreover, functional experiments revealed that up-regulation of miR-33a-5p inhibited cell proliferation and metastasis of ESCC cells. In addition, the expression level of miR-33a-5p was found to be negatively correlated with the long non-coding RNA (lncRNA) differentiation antagonizing non-protein coding RNA (DANCR), in both ESCC tissues and cell lines. Furthermore, zinc-finger-enhancer binding protein 1 (ZEB1) was predicted and confirmed to be a direct target of miR-33a-5p in ESCC. Further mechanistic investigation indicated that DANCR may function as a competing endogenous RNA (ceRNA) to sponge miR-33a-5p, and thereby up-regulate ZEB1 expression in ESCC. This study highlights the functions of miR-33a-5p in the progression of ESCC and suggests that the DANCR/miR-33a-5p/ZEB1 axis may be a potential prognostic and therapeutic target.