DDX11-AS1 modulates DNA damage repair to enhance paclitaxel resistance of lung adenocarcinoma cells.

Aim: To investigate the influence of DDX11-AS1 on paclitaxel (PTX) resistance in lung adenocarcinoma (LUAD). Methods: LncRNA expression and functional enrichment analyses were processed via bioinformatics methods. DDX11-AS1 expression was detected via quantitative real-time PCR. Cell counting kit-8, colony formation, flow cytometry and comet assays were manipulated to measure cell proliferation, apoptosis, cell cycle and DNA damage repair, respectively. Western blot was used to assess DNA damage-related protein expression. Results: DDX11-AS1 was in a high expression status in LUAD, and could promote LUAD cell proliferation and PTX resistance, while suppressing cell apoptosis. DNA damage repairing ability was also modulated by the change of DDX11-AS1 expression. Conclusion: LncRNA DDX11-AS1 promotes DNA damage repair to enhance PTX resistance in LUAD.

LncRNA DDX11-AS1 Promotes Chemoresistance through LIN28A-Mediated ATG12 mRNA Stabilization in Breast Cancer.

INTRODUCTION: During breast cancer chemotherapy, the chemoresistance that frequently accompanies the treatment has become a big challenge. Long noncoding RNAs (LncRNAs) have been related to the development of chemoresistance in multiple cancer types. LncRNA DDX11-AS1 has shown a carcinogenic role in lung and colorectal cancer and was reported to enhance oxaliplatin resistance in gastric cancer and Taxol insensitivity in esophageal cancer. But its role in breast cancer chemotherapy drug resistance remains unknown. This study aimed to investigate the function and mechanism of lncRNA DDX11-AS1 in breast cancer chemoresistance. METHODS: The relationship between DDX11-AS1 and adriamycin (ADR) resistance was confirmed by qPCR, cell viability tests, and survival analysis. Then, RNA immunoprecipitation was conducted to evaluate the interaction between DDX11-AS1 and RNA-binding protein LIN28A. The regulation effect of LIN28A on autophagy-related genes ATG7 or ATG12 was detected by RNA stability assay and Western blot. Their correlation analysis was evaluated in GEO datasets and further validated by immunohistochemical results. The clinical significance of DDX11-AS1, ATG7, or ATG12 was evaluated by Kaplan-Meier Plotter analysis. RESULTS: Here, we reported DDX11-AS1 was significantly upregulated in chemoresistant breast cancer cells and overexpression of DDX11-AS1 promoted ADR resistance in breast cancer. LIN28A could interact with DDX11-AS1 and was involved in DDX11-AS1-mediated ADR resistance. Interfering with LIN28A reversed DDX11-AS1-induced ADR resistance. LIN28A could increase the protein level of ATG7 and ATG12 by increasing their mRNA stability. Survival analysis showed that ATG12 expression level was negatively correlated with the prognosis of breast cancer patients. CONCLUSION: This study clarifies the role of DDX11-AS1 in breast cancer chemoresistance and revealed a new mechanism, that is, interacting with LIN28A to stabilize ATG7 and ATG12 and jointly promote chemorefractory. These findings warrant further in vivo investigations to study DDX11-AS1 as a potential target to overcome chemoresistance.

Long non-coding RNA DDX11-AS1 promotes the proliferation and migration of glioma cells by combining with HNRNPC.

Glioma is a malignant tumor of the central nervous system with complex pathogenesis, difficult operation, and a high postoperative recurrence rate. At present, there is still a lack of effective treatment. Long non-coding RNA DDX11 antisense RNA 1 (DDX11-AS1) has been shown to promote tumor development, such as hepatocellular carcinoma, esophageal cancer, etc. However, its molecular mechanism in glioma is poorly understood. In this study, we found that the expression of DDX11-AS1 was elevated in glioma tissues, and patients with high expression of DDX11-AS1 had poor prognosis. DDX11-AS1 was a potential prognostic marker. Functionally, DDX11-AS1 promoted glioma cell proliferation and migration. Mechanistically, DDX11-AS1 interacted with RNA-binding protein heterogeneous nuclear ribonucleoprotein C (HNRNPC) to promote Wnt/ß-catenin and AKT pathways and the epithelial-mesenchymal transition process. In summary, our study manifests that the DDX11-AS1/HNRNPC axis may play a vital part in the occurrence and development of glioma, which provides new ideas and therapeutic targets for the diagnosis, treatment, and prognosis of glioma.

LncRNA DDX11 antisense RNA 1 promotes EMT process of esophageal squamous cell carcinoma by sponging miR-30d-5p to regulate SNAI1/ZEB2 expression and Wnt/ß-catenin pathway.

LncRNA DDX11 antisense RNA 1 (DDX11-AS1) is recognized as having an imperative oncogenic role in different types of human cancer. Nevertheless, the functions, as well as the basic mechanisms of DDX11-AS1 in the EMT process of esophageal squamous cell carcinoma (ESCC), are yet to be clarified. In this research, high DDX11-AS1 expression was detected in ESCC cells as well as tissues and was linked to the poor prognosis of patients with ESCC. DDX11-AS1 promoted cell proliferation, migration, invasion ability and epithelial mesenchymal transition (EMT) process in vitro. Mechanistic analysis depicted that DDX11-AS1 may function as a ceRNA through sponging miR-30d-5p to upregulate the expression of SNAI1 and ZEB2. Meanwhile, overexpression of DDX11-AS1 might cause the activation of the Wnt/ß-catenin signaling pathway via targeting miR-30d-5p. On the whole, the findings of this research illustrate that DDX11-AS1 may act as an EMT-related lncRNA to advance ESCC progression through sponging miR-30d-5p to regulate SNAI1/ZEB2 expression and activate the Wnt/ß-catenin pathway, which indicates that it might serve as a probable therapeutic target for ESCC.

Landscape analysis of lncRNAs shows that DDX11-AS1 promotes cell-cycle progression in liver cancer through the PARP1/p53 axis.

Although long non-coding RNAs (lncRNAs) play important roles in tumorigenesis, the underlying mechanisms are unclear. Transcriptomic analysis of 33 hepatocellular carcinoma (HCC) samples revealed that the most enriched pathway for differentially expressed genes was related to the cell cycle process, where DDX11-AS1 is the most significant lncRNA. Upregulation of DDX11-AS1 expression through demethylation was significantly associated with a poor prognosis. Further mechanistic studies revealed that DDX11-AS1 promoted the growth of HCC by interacting with PARP1 through attenuating its binding to p53, leading to downregulated expression of p53 for inhibiting the transcription of downstream genes such as p21. Knockdown of DDX11-AS1 expression in xenograft mice using anti-DDX11-AS1 oligonucleotide suppressed liver tumor proliferation. These findings indicate that DDX11-AS1 plays a role in the development of liver cancer by affecting the cell cycle.

Long non-coding RNA DDX11-AS1 promotes esophageal carcinoma cell proliferation and migration through regulating the miR-514b-3p/RBX1 axis.

Esophageal carcinoma (ESCA) is one of the most aggressive malignancies with extremely high morbidity and mortality. At present, limited advancement in ESCA treatment has achieved. Therefore, it is urgent to explore the pathogenesis and progression mechanism of ESCA to provide the basis for the formulation of novel therapeutic strategies. Previous studies have found that long non-coding RNA (lncRNA) DDX11-AS1 expression enhances the paclitaxel resistance of ESCA cells. However, the mechanisms underlying the drug resistance conferred by lncRNA DDX11-AS1 in ESCA remains to be elucidated. Our research aims to clarify the role and mechanism of lncRNA DDX11-AS1 in regulating the progression of ESCA. We found that the expression of lncRNA DDX11-AS1 in ESCA tissues and cell lines was significantly upregulated. Subsequently, silencing lncRNA DDX11-AS1 significantly inhibited the proliferation, migration and invasion of ESCA cells, and induced the level of cell apoptosis. In terms of mechanism, our data showed that miR-514b-3p/RING box protein 1 (RBX1) axis played a crucial role in the oncogenic function of lncRNA DDX11-AS1. LncRNA DDX11-AS1 expression impaired the inhibitory function of miR-514b-3p on RBX1 through sponging effect. Taken together, our data support the notion that lncRNA DDX11-AS1 promotes the progression of ESCA through miR-514b-3p/RBX1 axis. Our research uncovers the novel regulatory role of lncRNA DDX11-AS1 in ESCA and lays a theoretical basis for developing novel treatment strategy of ESCA.

Silenced lncRNA DDX11-AS1 or up-regulated microRNA-34a-3p inhibits malignant phenotypes of hepatocellular carcinoma cells via suppression of TRAF5.

BACKGROUND: Studies have discussed long noncoding RNA DDX11-AS1 (DDX11-AS1)-mediated downstream mechanism in hepatocellular carcinoma (HCC). The goal of this study was to investigate the regulatory mechanism of DDX11-AS1-mediated microRNA-34a-3p (miR-34a-3p)/tumor necrosis factor receptor-associated factor 5 (TRAF5) axis on HCC cells. METHODS: DDX11-AS1, miR-34a-3p and TRAF5 expression levels in HCC were detected. The correlation of DDX11-AS1, miR-34a-3p and TRAF5 in HCC patients was analyzed by Pearson test. HCC cells were transfected with corresponding plasmid/oligonucleotide, and cell proliferation, migration, invasion, apoptosis and tumor formation ability were detected. Bioinformatics software, dual luciferase report experiment and RNA-pull down experiment analysis were applied to verify the targeting relationship between DDX11-AS1, miR-34a-3p and TRAF5. RESULTS: Elevated DDX11-AS1 and TRAF5 and reduced miR-34a-3p exhibited in HCC. Silenced DDX11-AS1 or up-regulated miR-34a-3p inhibited the proliferation, migration, invasion, promoted apoptosis of HCC cells and repressed the tumor growth in nude mice. In addition, DDX11-AS1 bound to miR-34a-3p to target TRAF5. Silencing TRAF5 or elevating miR-34a-3p expression mitigated up-regulated DDX11-AS1-mediated promotion of tumor growth. CONCLUSION: Silenced DDX11-AS1 or up-regulated miR-34a-3p inhibits HCC cell growth via elevation of TRAF5, which could be of great benefit to find early diagnostic markers for HCC patients.

LncRNA DDX11-AS1 Exerts Oncogenic Roles in Glioma Through Regulating miR-499b-5p/RWDD4 Axis.

BACKGROUND: Long noncoding RNAs (lncRNA) exert essential functions during tumorigenesis. However, how lncRNAs participate in glioma development remains poorly researched. This study aimed to determine how DDX11-AS1 affects glioma progression. METHODS: Gene expression was analyzed by qRT-PCR. Survival rate curve was plotted in 56 glioma patients. Loss-of-function assays were performed to analyze proliferation, migration, and invasion through CCK8, colony formation, and transwell assays. Luciferase assay and RNA pulldown assays were conducted to illustrate the underlying molecular mechanism. RESULTS: DDX11-AS1 expression was upregulated in glioma tissues and cells. DDX11-AS1 overexpression was linked with poor prognostic value. DDX11-AS1 knockdown suppressed proliferation, migration, and invasion while inducing apoptosis. DDX11-AS1 interacted with miR-499b-5p to eliminate it, leading to upregulation of RWDD4 expression. RWDD4 was upregulated in glioma while miR-499b-5p was downregulated. CONCLUSION: DDX11-AS1 upregulation promotes glioma progression through acting as a competing endogenous RNA for miR-499b-5p to upregulate RWDD4.

LncRNA DDX11-AS1 accelerates hepatocellular carcinoma progression via the miR-195-5p/MACC1 pathway.

INTRODUCTION AND AIM: Long non-coding RNA (lncRNA) has been shown to be a vital regulator of cancer progression, including hepatocellular carcinoma (HCC). However, the role of DEAD/H box protein 11 antisense RNA 1 (DDX11-AS1) in HCC remains to be further studied. MATERIAL AND METHODS: The expression levels of DDX11-AS1, miR-195-5p and metastasis-associated in colon cancer-1 (MACC1) were determined by quantitative real-time PCR (qRT-PCR). Cell counting kit-8 (CCK-8), transwell and apoptosis determination assays were used to evaluate cell proliferation, migration, invasion and apoptosis, respectively. Mice xenograft models were constructed to verify the effect of DDX11-AS1 on HCC tumor growth in vivo. Furthermore, lactate production, glucose consumption, ATP level and glucose uptake were detected to assess cell glucose metabolism. The interactions among DDX11-AS1, miR-195-5p and MACC1 were verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Moreover, western blot (WB) analysis was performed to evaluate the protein levels. RESULTS: DDX11-AS1 was upregulated in HCC tissues and cells, and its silencing could inhibit HCC cell proliferation, migration, invasion and glucose metabolism, and promote apoptosis in vitro. Also, DDX11-AS1 knockdown reduced HCC tumor growth in vivo. Besides, DDX11-AS1 could interact with miR-195-5p, and miR-195-5p inhibitor reversed the inhibitory effect of silenced DDX11-AS1 on HCC cell progression. In addition, MACC1 was a target of miR-195-5p, and its overexpression reversed the suppression effect of miR-195-5p on HCC cell progression. CONCLUSION: Our data revealed that DDX11-AS1 could act as an oncogenic regulator in HCC, providing a potential therapeutic target for HCC treatment.

LncRNA DDX11-AS1 Promotes Bladder Cancer Occurrence Via Protecting LAMB3 from Downregulation by Sponging miR-2355-5p.

Background: As a subtype of human genitourinary system cancer, the morbidity of bladder cancer (BC) continues to rise. Because of the high potentiality of cell metastasis, the 5-year survival rate of BC is relatively low. Long noncoding RNAs (lncRNAs) have been verified by a large body of literature to engage in the tumorigenesis of a few cancers. DDX11-AS1 has been elucidated as a malignancy promoter in several cancers; therefore, its mysterious role in BC attracted our interest as being well worth investigating. Aim of the Study: The primary consideration of this article was to clarify the part that DDX11-AS1 plays in the progression of BC. Methods: The expression of DDX11-AS1 in BC was revealed by quantitative real-time polymerase chain reaction. The biological functions of DDX11-AS1 in BC were evaluated through CCK-8 (Cell Counting Kit-8), EDU, TUNEL (TdT-mediated dUTP nick-end labeling), flow cytometry analysis, and Western Blot assays. Luciferase or RNA immunoprecipitation assay was used to investigate the interaction between miR-2355-5p and DDX11-AS1 (or LAMB3). Results: DDX11-AS1 manifested remarkably high level in BC and promoted the malignancy of BC. Moreover, miR-2355-5p was validated to be able to bind with DDX11-AS1 and inhibit cell proliferation in BC. Furthermore, our data suggested that LAMB3 expression was evidently upregulated in BC cells and inversely modulated by miR-2355-5p. Besides, LAMB3 may bind with miR-2355-5p. Ultimately, rescue assays indicated that the restrained development of BC in sh-DDX11-AS1#1-transfected cells could be restored by enforced expression of LAMB3. Conclusion: DDX11-AS1 facilitates the tumorigenesis of BC by the miR-2355-5p/LAMB3 axis.

DDX11-AS1exacerbates bladder cancer progression by enhancing CDK6 expression via suppressing miR-499b-5p.

PURPOSE: We investigated DDX11-AS1 effects on bladder cancer (BLCA) progression to identify a new potential therapeutic target for BLCA. METHODS: BLCA cases (n = 108) were enrolled. SW780 and J82 cells were transfected. Cell counting kit-8 (CCK-8) assay, wound healing assay and transwell migration assay was conducted. Cell cycle and apoptosis was detected by flow cytometry. Luciferase reporter assay was performed. DDX11-AS1, miR-499b-5p and CDK6 mRNA expression in tissues/cells was determined by quantitative real-time polymerase chain reaction (qRT-PCR). In vivo experiment was performed using nude mice. CDK6 and Ki67 proteins expression in cells and xenograft tumors were researched by Western blot and immunohistochemistry. RESULTS: Overexpressed DDX11-AS1 in BLCA was associated with poor outcome of patients. Compared with siCtrl group, SW780 and J82 cells of siDDX11-AS1 group had lower OD450 value (P < 0.01), less cells in S phase, more apoptosis cells (P < 0.05), higher relative wound width (P < 0.05) and less invasive cell number (P < 0.01). DDX11-AS1 promoted CDK6 expression via inhibiting miR-499b-5p. Compared with oe-DDX11-AS1 group, SW780 cells of oe-DDX11-AS1 + miR-499b-5p mimic group and oe-DDX11-AS1 + siCDK6 group had lower OD450 value (P < 0.01), less cells in S phrase, more apoptosis cells (P < 0.01), higher relative wound width (P < 0.05) and less invasive cell numbers (P < 0.01). DDX11-AS1 knockdown inhibited SW780 cells growth in vivo and suppressed CDK6 and Ki67 expression in xenograft tumors. CONCLUSION: DDX11-AS1 exacerbates BLCA progression by enhancing CDK6 expression via suppressing miR-499b-5p.

Long non-coding RNA DDX11-AS1 promotes non-small cell lung cancer development via regulating PI3K/AKT signalling.

Non-small cell lung cancer (NSCLC) has been considered to be the most common category of lung cancer, comprising approximately 80% of lung cancers. Long non-coding RNAs (lncRNAs) were diffusely documented to modulate carcinogenesis or progression of tumours. However, the role of DDX11-AS1 was still unclear in NSCLC. Bioinformatics analysis and experimental assays including hematoxylin and eosin (H&E) staining, RT-qPCR, colony formation, CCK-8, flow cytometry, western blot and xenograft assays were applied to investigate the biological role and molecular mechanism of DDX11-AS1 in NSCLC. The level of lncRNA DDX11-AS1 was up-regulated in NSCLC tumour tissues and cells. In function aspect, knockdown of DDX11-AS1 caused an apparent inhibitive effect on cell proliferation in vitro and in vivo. DDX11-AS1 inhibition promoted cell apoptosis in vitro. In mechanism, the protein level of phosphorylated AKT was reduced by DDX11-AS1 inhibition but increased by DDX11-AS1 overexpression. These results indicated that DDX11-AS1 exacerbated NSCLC progression via activating PI3K/AKT signalling pathway. All in all, DDX11-AS1 promotes NSCLC development via regulating PI3K/AKT signalling.

DDX11-AS1 contributes to osteosarcoma progression via stabilizing DDX11.

Increasing evidence has uncovered that long noncoding RNAs (lncRNAs) play extremely important roles in numerous steps of gene regulation concerning the progression of tumors. Defined as a kind of lncRNA, DDX11-AS1 has been considered to be closely related to the tumorigenesis of malignancies. Nevertheless, the underlying regulatory role of it in osteosarcoma remains to be analyzed and elucidated. In this research, a dramatically upregulated expression of DDX11-AS1 was detected in osteosarcoma cells. Loss-of-function assays revealed that decreased expression of DDX11-AS1 impaired osteosarcoma cell proliferation, metastasis as well as epithelial-mesenchymal transition (EMT) process. Afterwards, molecular mechanism tests validated that DDX11-AS1 could sponge miR-873-5p to upregulate DDX11 expression in osteosarcoma. Additionally, functional tests delineated that upregulation of miR-873-5p inhibited cell proliferation, metastasis as well as EMT process in osteosarcoma progression. Further, DDX11-AS1 was verified to regulate the mRNA stability of DDX11 through binding with IGF2BP2 in osteosarcoma. Final rescue tests in vitro and in vivo further elucidated that DDX11 overexpression could reversed the DDX11-AS1 downregulation-mediated effect on osteosarcoma progression. To sum up, DDX11-AS1 contributes to osteosarcoma progression via stabilizing DDX11.

Long non-coding RNA DDX11-AS1 facilitates gastric cancer progression by regulating miR-873-5p/SPC18 axis.

Gastric cancer (GC) is a malignant tumour with high lethality. Accruing evidence elucidates the critical adjusting role of long non-coding RNA (lncRNAs) in human cancers. DDX11 antisense RNA 1 (DDX11-AS1) was previously found to be involved in GC pathogenesis. However, the precise molecular mechanisms of DDX11-AS1 need to be further investigated. In this study, we found that DDX11-AS1 expression was up-regulated in GC tumour tissues and cells. Increased DDX11-AS1 expression was associated with advanced TNM stage and lymph node metastasis. Functionally, knockdown of DDX11-AS1 repressed cell proliferation and clone formation, while induced cell cycle arrest and apoptosis. As expected, DDX11-AS1 overexpression displayed the opposite effect. Mechanically, DDX11-AS1 enhanced SPC18 expression through acting as a ceRNA for miR-873-5p. Furthermore, the inhibitory effect of DDX11-AS1 silencing on malignant biological behaviour of GC cells was attenuated by either miR-873-5p inhibitor or SEC11A up-regulation. Moreover, suppression of DDX11-AS1 also decreased GC tumorigenesis in vivo. In conclusion, DDX11-AS1 may serve as an oncogene in GC progression by sponging miR-873-5p and promoting SPC18 expression, providing a new insight into the mechanisms of DDX11-AS1 and elucidating a promising therapy target in GC.

Mechanism of LncRNA DDX11-AS1 in Regulating Proliferation, Migration and Apoptosis of Gastric Cancer Cells by Targeting MiR-497-5p / 胃肠病学

Background: LncRNA expression was up-regulated or down-regulated in gastric cancer, but the mechanism of role of LncRNA in the development and progression of gastric cancer was not been fully clarified. Aims: To investigate the mechanism of LncRNA DDX11-AS1 in regulating the proliferation, migration and apoptosis of gastric cancer cells by targeting the expression of miR-497-5p. Methods: qRT-PCR was used to detect the expressions of DDX11-AS1 and miR-497-5p in gastric cancer tissue and cell lines. Pearson method was used to analyze the correlation between DDX11-AS1 and miR-497-5p in gastric cancer tissue. Gastric cancer HGC-27 cells were randomly divided into NC group, si-con group, si-DDX11-AS1 group, miR-con group, miR-497-5p group, si-DDX11-AS1+anti-miR-con group, si-DDX11-AS1+anti-miR-497-5p group. The cell proliferation was detected by MTT. The cell apoptosis was detected by flow cytometry. Transwell assay was used to detect the migration and invasion ability. The dual luciferase reporter system assay was used to verify the targeted regulatory relationship between DDX11-AS1 and miR-497-5p. The protein expressions of cyclin D1, cleaved caspase-3, MMP-2 and MMP-9 were detected by Western blotting. Results: The expression of DDX11-AS1 in gastric cancer tissue and cell lines was significantly increased (P<0.05), while the expression of miR-497-5p was significantly decreased (P<0.05), DDX11-AS1 was negatively correlated with miR-497-5p (r=-0.754, P<0.05). Interfering the expression of DDX11-AS1 or up-regulating the expression of miR-497-5p significantly inhibited cell proliferation, migration and invasion (P<0.05), apoptosis rate was significantly increased (P<0.05), and the expressions of cyclin D1, MMP-2 and MMP-9 were significantly decreased (P<0.05), and the expression of cleaved caspase-3 was significantly increased (P<0.05). The dual luciferase reporter assay demonstrated that DDX11-AS1 negatively regulated the expression and activity of miR-497-5p. Inhibition of miR-497-5p expression reversed the effect of interference with DDX11-AS1 expression on the biological behavior of gastric cancer cells. Conclusions: Interference with LncRNA DDX11-AS1 expression can inhibit the proliferation, migration, invasion and induce apoptosis of gastric cancer cells by targeting and up-regulating the expression of miR-497-5p.

The resistance of esophageal cancer cells to paclitaxel can be reduced by the knockdown of long noncoding RNA DDX11-AS1 through TAF1/TOP2A inhibition.

Esophageal cancer (EC) is one of the most common malignancies in the world. The currently used chemotherapeutic drug for the treatment of EC is paclitaxel (PTX), the efficacy of which is affected by the development of drug resistance. The present study aims to define the role of the long noncoding RNA (lncRNA) DDX11-AS1 in the progression of EC with the involvement of PTX-resistant EC cells. First, EC and adjacent normal tissue samples were collected from 82 patients with EC, after which the expression levels of DDX11-AS1, TOP2A and TAF1 were determined. The results showed that DDX11-AS1, TOP2A and TAF1 were highly expressed in EC tissues, and there was a positive correlation between the expression levels of DDX11-AS1 and TOP2A. A PTX-resistant EC cell line was constructed. Next, we evaluated the effects of DDX11-AS1 and TOP2A on the resistance of EC cells to PTX, and the regulatory relationships between DDX11-AS1, TOP2A and TAF1 were investigated. DDX11-AS1 could promote TOP2A transcription via TAF1, and the knockdown of TOP2A or DDX11-AS1 could increase the sensitivity of EC cells to PTX. The effect of DDX11-AS1 on the growth of PTX-inhibited tumors was confirmed using a tumor formation assay in nude mice. It was verified that knocking down DDX11-AS1 reduced the expression level of TOP2A and inhibited tumor growth. In conclusion, our findings suggest that DDX11-AS1 knockdown results in reduced resistance of EC cells to PTX by inhibiting TOP2A transcription via TAF1. Therefore, DDX11-AS1 knockdown could be a promising therapeutic strategy for EC.

Long noncoding RNA DDX11-AS1 epigenetically represses LATS2 by interacting with EZH2 and DNMT1 in hepatocellular carcinoma.

Long noncoding RNAs (lncRNAs), a group of transcripts without protein coding potential, have been reported to play critical roles in progression of hepatocellular carcinoma (HCC). However, the biological role of DDX11-AS1 in HCC is not clear. In this study, we found that DDX11-AS1 expression was dramatically higher in HCC tissues and cell lines. Higher DDX11-AS1 expression predicted poor overall survival of patients. Functionally, the proliferation, cell cycle progression, migration, and invasion of HCC cells were inhibited by DDX11-AS1 silencing, while promoted by ectopic expression of DDX11-AS1. RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP) assays validated that DDX11-AS1 suppressed LATS2 expression by interacting with EZH2 and DNMT1 in HCC cells. Knockdown of DDX11-AS1 increased the mRNA and protein levels of LATS2. Overexpression of LATS2 abolished the promotive effect of DDX11-AS1 on cell growth and invasion. Besides, DDX11-AS1 promoted tumor formation in vivo. The mRNA levels of LATS2 were markedly decreased in tumor tissues and negatively correlated with DDX11-AS1 expression. Taken together, our data indicated that DDX11-AS1 may be a novel oncogene in hepatocarcinogenesis by repressing LATS2, providing a potential therapeutic target for HCC treatment.

Integrative Analysis of Dysregulated lncRNA-Associated ceRNA Network Reveals Functional lncRNAs in Gastric Cancer.

Mounting evidence suggests that long noncoding RNAs (lncRNAs) play important roles in the regulation of gene expression by acting as competing endogenous RNA (ceRNA). However, the regulatory mechanisms of lncRNA as ceRNA in gastric cancer (GC) are not fully understood. Here, we first constructed a dysregulated lncRNA-associated ceRNA network by integrating analysis of gene expression profiles of lncRNAs, microRNAs (miRNAs), and messenger RNAs (mRNAs). Then, we determined three lncRNAs (RP5-1120P11, DLEU2, and DDX11-AS1) as hub lncRNAs, in which associated ceRNA subnetworks were involved in cell cycle-related processes and cancer-related pathways. Furthermore, we confirmed that the two lncRNAs (DLEU2 and DDX11-AS1) were significantly upregulated in GC tissues, promote GC cell proliferation, and negatively regulate miRNA expression, respectively. The hub lncRNAs (DLEU2 and DDX11-AS1) could have oncogenic functions, and act as potential ceRNAs to sponge miRNA. Our findings not only provide novel insights on ceRNA regulation in GC, but can also provide opportunities for the functional characterization of lncRNAs in future studies.

DDX11-AS1 as potential therapy targets for human hepatocellular carcinoma.

Hepatocellular Carcinoma (HCC) is one of the most fatal cancers, whose incidence and death rates are still rising. Here, we report the identification of long non-coding RNAs (IncRNAs) that associated with HCC progression and metabolism based on the systematically analysis of large scale RNA-seq data from HCC patients. We identified seven lncRNAs with high confidence which were highly related with prognostic of HCC. Of note, three of them had quite different expression patterns between the control samples and the patients, and their critical roles in cancer progression were validated. We proposed that DDX11-AS1 play important role during HCC oncogenesis and may serve as potential therapy target for HCC.