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Long noncoding RNAs (lncRNAs) are RNA molecules of 200 nucleotides or more in length that are not translated into proteins. Their expression is tissue-specific, with the vast majority involved in the regulation of cellular processes and functions. Many human diseases, including cancer, have been shown to be associated with deregulated lncRNAs, rendering them potential therapeutic targets and biomarkers for differential diagnosis. The expression of lncRNAs in the nervous system varies in different cell types, implicated in mechanisms of neurons and glia, with effects on the development and functioning of the brain. Reports have also shown a link between changes in lncRNA molecules and the etiopathogenesis of brain neoplasia, including glioblastoma multiforme (GBM). GBM is an aggressive variant of brain cancer with an unfavourable prognosis and a median survival of 14–16 months. It is considered a brain-specific disease with the highly invasive malignant cells spreading throughout the neural tissue, impeding the complete resection, and leading to post-surgery recurrences, which are the prime cause of mortality. The early diagnosis of GBM could improve the treatment and extend survival, with the lncRNA profiling of biological fluids promising the detection of neoplastic changes at their initial stages and more effective therapeutic interventions. This review presents a systematic overview of GBM-associated deregulation of lncRNAs with a focus on lncRNA fingerprints in patients' blood. [ABSTRACT FROM AUTHOR]

Purpose: To investigate whether long noncoding RNAs (lncRNAs) are involved in the development or malignant behavior of ovarian high‐grade serous carcinoma (HGSC), we attempted to identify lncRNAs specific to HGSC. Methods: Total RNAs were isolated from HGSC, normal ovarian, and fallopian tube tissue samples and were subjected to a PCR array that can analyze 84 cancer‐associated lncRNAs. The lncRNAs that were upregulated and downregulated in HGSC in comparison to multiple samples of normal ovary and fallopian tube were validated by real‐time RT‐PCR. To infer the function, ovarian cancer cell lines that overexpress the identified lncRNAs were established, and the activation of cell proliferation, migration, and invasion was analyzed. Results: Eleven lncRNAs (ACTA2‐AS1, ADAMTS9‐AS2, CBR3‐AS1, HAND2‐AS1, IPW, LINC00312, LINC00887, MEG3, NBR2, TSIX, and XIST) were downregulated in HGSC samples. We established the cell lines that overexpress ADAMTS9‐AS2, CBR3‐AS1, or NBR2. In cell lines overexpressing ADAMTS9‐AS2, cell proliferation was suppressed, but migration and invasion were promoted. In cell lines overexpressing CBR3‐AS1 or NBR2, cell migration tended to be promoted, although cell proliferation and invasion were unchanged. Conclusion: We identified eleven lncRNAs that were specifically downregulated in HGSC. Of these, CBR3‐AS1, NBR2, and ADAMTS9‐AS2 had unique functions in the malignant behaviors of HGSC. [ABSTRACT FROM AUTHOR]

This study explored the mechanism that ADAMTS9-AS2/miR-196b-5p/PPP1R12B/cell cycle pathway axis in inhibiting the malignant progression of esophageal cancer (EC), providing a new idea for targeted molecular therapy of EC. The expression data of EC tissue were acquired from TCGA database. The target lncRNA, downstream miRNA and its target gene were determined by bioinformatics analysis. ADAMTS9-AS2, miR-196b-5p and PPP1R12B levels in EC tissue and cells were assayed through qRT-PCR. Western blot was applied to assess protein level of PPP1R12B in cells and tissues, as well as protein expression of CDK1, cyclin A2, cyclin B1 and Plk1 in EC cells. Cell proliferation was assayed via CCK-8 assay. Cell cycle distribution was analyzed by flow cytometry. Cell migratory and invasive abilities were measured through scratch healing and transwell assays. Pearson correlation analysis was utilized to analyze relationship among ADAMTS9-AS2, miR-196b-5p and PPP1R12B. RIP was introduced to assess binding among the three. Dual-luciferase assay was utilized to verify targeted binding sites. The tumor formation in nude mice assay was utilized to detect tumorigenesis of EC cells in vivo. ADAMTS9-AS2 was significantly lowly expressed while miR-196b-5p was increased in EC tissue and cells. ADAMTS9-AS2 bound to miR-196b-5p and constrained its expression. Overexpressed ADAMTS9-AS2 inhibited EC cell malignant progression via downregulating miR-196b-5p, while overexpressed miR-196b-5p reversed this inhibitory effect. ADAMTS9-AS2 modulated PPP1R12B level by competitively inhibiting miR-196b-5p. PPP1R12B played a modulatory role in EC by inhibiting cell cycle pathway. Overexpressed ADAMTS9-AS2 regulated the tumor-forming ability of EC cells in vivo through miR-196b-5p/PPP1R12B/cell cycle signaling pathway axis. ADAMTS9-AS2 downregulated PPP1R12B by adsorbing miR-196b-5p, so as to regulate the cell cycle signaling pathway to inhibit EC malignant progression. [ABSTRACT FROM AUTHOR]

Ischemic stroke is a common disease threatening human health. ADAMTS9-AS2 is a lncRNA that has been widely studied in tumors, but not in ischemic stroke. The purpose of this study was to investigate the role and potential molecular mechanism of ADAMTS9-AS2 in endothelial cell function after ischemic stroke in vivo and in vitro. The results showed that ADAMTS9-AS2 was decreased in the plasma of acute ischemic stroke (AIS) patients and in the brain tissue and plasma of MCAO mice, and the low expression of ADAMTS9-AS2 was associated with the increase in infarct size. Besides, compared with the control group, MCAO treatment slightly promoted angiogenesis, which was enhanced by the overexpression of ADAMTS9-AS2. Molecular mechanism results indicated that ADAMTS9-AS2 and miR-185-5p affected the pathological process of ischemic stroke through ceRNA mechanism, and IGFBP-2 was a downstream target gene of miR-185-5p. These findings demonstrated that ADAMTS9-AS2 promoted angiogenesis through regulating miR-185-5p/IGFBP-2 axis, suggesting that ADAMTS9-AS2 may be a potential marker for the diagnosis and treatment of neurological diseases. [ABSTRACT FROM AUTHOR]

Background: Long non‐coding RNA ADAM metallopeptidase with thrombospondin type 1 motif, 9 antisense RNA 2 (ADAMTS9‐AS2) was recognized as a novel tumor suppressor and plays an important role in the initiation and progression of malignant behavior in human cancers, although its plasma expression and clinical value in patients with non‐small cell lung cancer (NSCLC) remain unknown. We aimed to analyze the diagnostic role of ADAMTS9‐AS2 and cytokeratin 19 fragmentation antigen (CYFRA 21‐1) in NSCLC. Methods: The present study included 80 control subjects, 80 patients with benign lung lesion and 80 NSCLC patients. The expression of ADAMTS9‐AS2 in the tissue and plasma was detected by a real‐time polymerase chain reaction. Serum CYFRA 21‐1 was analyzed using an enzyme‐linked immunosorbent assay. Results: In comparison with benign lung lesion and controls, tissue and plasma ADAMTS9‐AS2 expression were significantly down‐regulated in NSCLC (p < 0.001). Decreased ADAMTS9‐AS2 expression was associated with TNM stages in NSCLC patients (p < 0.001). Up‐regulation of CYFRA 21‐1 was reported among NSCLC patients and it was associated with TNM staging. Tissue and plasma ADAMTS9‐AS2 expression levels were the predicting factors for NSCLC and they both correlated negatively with CYFRA 21‐1 levels. Plasma ADAMTS9‐AS2 levels had a significant positive correlation with their tumor tissue levels. Plasma ADAMTS9‐AS2 showed a higher sensitivity (95%) and specificity (99.1%) in the diagnosis of NSCLC than CYFRA 21‐1 (61.3% sensitivity and 60% specificity). Conclusions: Our results suggested that decreased plasma ADAMTS9‐AS2 expression might act as a novel non‐invasive tumor biomarker in NSCLC diagnosis. Furthermore, plasma ADAMTS9‐AS2 might predict aggressive tumor behavior. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common malignancy among women, with the highest incidence rate worldwide. Dysregulation of long noncoding RNAs during the preliminary stages of breast carcinogenesis is poorly understood. In this study, we performed RNA sequencing to identify long noncoding RNA expression profiles associated with early‐stage breast cancer. RNA sequencing was performed on six invasive ductal carcinoma (IDC) tissues along with paired normal tissue samples, seven ductal carcinoma in situ tissues, and five apparently normal breast tissues. We identified 375 differentially expressed lncRNAs (DElncRNAs) in IDC tissues compared to paired normal tissues. Antisense transcripts (~ 58%) were the largest subtype among DElncRNAs. About 20% of the 375 DElncRNAs were supported by typical split readings leveraging their detection confidence. Validation was performed in n = 52 IDC and paired normal tissue by qRT‐PCR for the identified targets (ADAMTS9‐AS2, EPB41L4A‐AS1, WDFY3‐AS2, RP11‐295M3.4, RP11‐161M6.2, RP11‐490M8.1, CTB‐92J24.3, and FAM83H‐AS1). We evaluated the prognostic significance of DElncRNAs based on TCGA datasets and report that overexpression of FAM83H‐AS1 was associated with patient poor survival. We confirmed that the downregulation of ADAMTS9‐AS2 in breast cancer was due to promoter hypermethylation through in vitro silencing experiments and pyrosequencing.

Long non-coding RNAs (lncRNAs), as competitive endogenous RNAs (ceRNAs), play a critical role in biological processes of cancer. However, the roles of specific lncRNAs in ceRNA network of lung adenocarcinoma (LUAD) remains largely unclear. Herein, we identified the roles of lncRNA ADAMTS9-AS1/AS2 (ADAMTS-AS1/AS2) in lung adenocarcinoma by bioinformatics analyses and functional verification. First, differentially expressed genes ADAMTS9-AS1, ADAMTS9-AS2 and ADAMTS9 were screened out from GSE130779. Then the expression correlation of these three genes was analyzed. The results showed that ADAMTS9-AS1, ADAMTS9-AS2 and ADAMTS9 were down-regulated in LUAD, and were positively correlated with each other. After that, miRcode was used to find miR-150 which binds to ADAMTS9-AS1/ADAMTS9-AS2/ADAMTS9. Next, co-expression analysis and functional enrichment analyses were performed to further analyze differentially expressed genes. The results showed that the differentially expressed genes were mainly enriched in Beta3 integrin cell surface interactions and epithelial-to-mesenchymal transition. Finally, the cell functions of ADAMTS9-AS1 and ADAMTS9-AS2 in A549 and NCI-H1299 cell lines were verified. In vitro cell studies confirmed that ADAMTS9-AS1 and ADAMTS9-AS2 play an inhibitory role in LUAD cells.

BackgroundLong non-coding RNAs (lncRNAs) are key regulators of triple-negative breast cancer (TNBC) progression, but further work is needed to fully understand the functional relevance of these non-coding RNAs in this cancer type. Herein, we explored the functional role of the lncRNA ADAMTS9-AS2 in TNBC.MethodsNext-generation sequencing was conducted to compare the expression of different lncRNAs in TNBC tumor and paracancerous tissues, after which ADAMTS9-AS2differential expression in these tumor tissues was evaluated via qPCR. The functional role of this lncRNA was assessed by overexpressing it in vitro and in vivo. FISH and PCR were used to assess the localization of ADAMTS9-AS2within cells. Downstream targets of ADAMTS9-AS2 signaling were identified via RNA pulldown assays and transcriptomic sequencing.ResultsThe expression ofADAMTS9-AS2 was decreased in TNBC tumor samples (P < 0.05), with such downregulation being correlated with TNM stage, age, and tumor size. Overexpressing ADAMTS9-AS2 promoted the apoptotic death and cell cycle arrest of tumor cells in vitro and inhibited tumor growth in vivo. From a mechanistic perspective, ADAMTS9-AS2 was found to control the expression of RPL22 and to thereby modulate TGF-β signaling to control TNBC progression.ConclusionADAMTS9-AS2 controls the expression of RPL22 and thereby regulates TNBC malignancy via the TGF-β signaling pathway.

Long non-coding RNAs (lncRNAs), as competitive endogenous RNAs (ceRNAs), play a critical role in biological processes of cancer. However, the roles of specific lncRNAs in ceRNA network of lung adenocarcinoma (LUAD) remains largely unclear. Herein, we identified the roles of lncRNA ADAMTS9-AS1/AS2 (ADAMTS-AS1/AS2) in lung adenocarcinoma by bioinformatics analyses and functional verification. First, differentially expressed genes ADAMTS9-AS1, ADAMTS9-AS2 and ADAMTS9 were screened out from GSE130779. Then the expression correlation of these three genes was analyzed. The results showed that ADAMTS9-AS1, ADAMTS9-AS2 and ADAMTS9 were down-regulated in LUAD, and were positively correlated with each other. After that, miRcode was used to find miR-150 which binds to ADAMTS9-AS1/ADAMTS9-AS2/ADAMTS9. Next, co-expression analysis and functional enrichment analyses were performed to further analyze differentially expressed genes. The results showed that the differentially expressed genes were mainly enriched in Beta3 integrin cell surface interactions and epithelial-to-mesenchymal transition. Finally, the cell functions of ADAMTS9-AS1 and ADAMTS9-AS2 in A549 and NCI-H1299 cell lines were verified. In vitro cell studies confirmed that ADAMTS9-AS1 and ADAMTS9-AS2 play an inhibitory role in LUAD cells. [ABSTRACT FROM AUTHOR]

Background: Long non-coding RNAs (lncRNAs) are key regulators of triple-negative breast cancer (TNBC) progression, but further work is needed to fully understand the functional relevance of these non-coding RNAs in this cancer type. Herein, we explored the functional role of the lncRNA ADAMTS9-AS2 in TNBC. Methods: Next-generation sequencing was conducted to compare the expression of different lncRNAs in TNBC tumor and paracancerous tissues, after which ADAMTS9-AS2differential expression in these tumor tissues was evaluated via qPCR. The functional role of this lncRNA was assessed by overexpressing it in vitro and in vivo. FISH and PCR were used to assess the localization of ADAMTS9-AS2within cells. Downstream targets of ADAMTS9-AS2 signaling were identified via RNA pulldown assays and transcriptomic sequencing. Results: The expression ofADAMTS9-AS2 was decreased in TNBC tumor samples (P < 0.05), with such downregulation being correlated with TNM stage, age, and tumor size. Overexpressing ADAMTS9-AS2 promoted the apoptotic death and cell cycle arrest of tumor cells in vitro and inhibited tumor growth in vivo. From a mechanistic perspective, ADAMTS9-AS2 was found to control the expression of RPL22 and to thereby modulate TGF-β signaling to control TNBC progression. Conclusion: ADAMTS9-AS2 controls the expression of RPL22 and thereby regulates TNBC malignancy via the TGF-β signaling pathway. [ABSTRACT FROM AUTHOR]

Oral submucosal fibrosis (OSF) is one of the pre‐cancerous lesions of oral squamous cell carcinoma (OSCC). Its malignant rate is increasing, but the mechanism of malignancy is not clear. We previously have elucidated the long non‐coding RNA (lncRNA) expression profile during OSF progression at the genome‐wide level. However, the role of lncRNA ADAMTS9‐AS2 in OSF progression via extracellular communication remains unclear. lncRNA ADAMTS9‐AS2 is down‐regulated in OSCC tissues compared with OSF and normal mucous tissues. Low ADAMTS9‐AS2 expression is associated with poor overall survival. ADAMTS9‐AS2 is frequently methylated in OSCC tissues, but not in normal oral mucous and OSF tissues, suggesting tumour‐specific methylation. Functional studies reveal that exosomal ADAMTS9‐AS2 suppresses OSCC cell growth, migration and invasion in vitro. Mechanistically, exosomal ADAMTS9‐AS2 inhibits AKT signalling pathway and regulates epithelial‐mesenchymal transition markers. Through profiling miRNA expression profile regulated by exosomal ADAMTS9‐AS2, significantly enriched pathways include metabolic pathway, PI3K‐Akt signalling pathway and pathways in cancer, indicating that exosomal ADAMTS9‐AS2 exerts its functions through interacting with miRNAs during OSF progression. Thus, our findings highlight the crucial role of ADAMTS9‐AS2 in the cell microenvironment during OSF carcinogenesis, which is expected to become a marker for early diagnosis of OSCC. [ABSTRACT FROM AUTHOR]

The long-chain noncoding RNA ADAMTS9-AS2 functions as a tumor suppressor gene in many cancers. However, the underlying mechanism remains to be fully elucidated in bladder cancer (BC). ADAMTS9-AS2 exhibited a lower expression level in BC samples and cell lines. In addition, overexpression of ADAMTS9-AS2 obviously suppressed proliferation and migration, and induced apoptosis of T24 cells, while transfection with the ADAMTS9-AS2 inhibitor had opposite results in 5637 cells. Furthermore, miR-182-5p was the target microRNA of ADAMTS9-AS2 and was negatively correlated with ADAMTS9-AS2 expression. Upregulation of miR-182-5p reversed the effects of ADAMTS9-AS2 overexpression on biological function in T24 cells. ADAMTS9-AS2 was a tumor suppressor that inhibited BC cell proliferation and induced cellular apoptosis by targeting miR-182-5p, and it could be a promising target for BC treatment. [ABSTRACT FROM AUTHOR]

Nowadays, research on CSCs is still in an initial stage, and there are few studies reporting the successful isolation and identification of CSCs. In the present study, we attempted to isolate CSCs through cultivating the cell line MKN45 in defined serum‐free medium and study the expression of stem cell markers or related proteins (Oct3/4, Sox2, Nanog and CD44) in CSCs. Moreover, immunofluorescence staining was performed to validate the stem cell markers of spheroid body‐forming cells. Further experiments were used to evaluate the SPOP expression in tumorsphere cells. In addition, ADAMTS9‐AS2 is a lncRNA that contributes to the genesis and development of many cancers, including gastric cancer (GC). We found ADAMTS9‐AS2 functioned as an anti‐oncogene and positively correlated with the expression of SPOP in GC tissues by combining bioinformatics analyses. Furthermore, we reported that ADAMTS9‐AS2 regulated the expression of SPOP in GC cells and tumorsphere cells to inhibit GC progression. Together, our results demonstrated that SPOP and ADAMTS9‐AS2 can be potential targets for GC treatment. [ABSTRACT FROM AUTHOR]

BackgroundLncRNAs have been shown to play essential roles in cancer therapeutic response. However, the detailed mechanism of lncRNAs in temozolomide (TMZ) resistance in glioblastoma (GBM) remain to be elucidated.MethodsTo elucidate the mechanism maintaining TMZ resistance, we constructed two TMZ-resistant GBM cell lines (T98G-R/U118-R). LncRNAs from four public datasets were reanalyzed, and the candidate lncRNA ADAMTS9-AS2 was evaluated in TMZ-treated GBM patients and in vitro cell lines.ResultsReanalysis of lncRNA expression profiles identified ADAMTS9-AS2 as significantly overexpressed in TMZ-resistant GBM cells and as positively associated with the IC50 of TMZ in GBM cells. Overexpression of ADAMTS9-AS2 was also significantly associated with poor TMZ response and shorter progression-free survival (PFS) in TMZ-treated GBM patients. Knockdown of ADAMTS9-AS2 inhibited proliferation and attenuated the IC50 of TMZ, as well as mitigating invasion and migration in TMZ-resistant GBM cells. Subsequent investigations indicated that reduced expression of ADAMTS9-AS2 significantly suppressed expression of the FUS protein, which was predicted as a direct substrate of ADAMTS9-AS2. Expression trends of FUS were directly correlated with those of ADAMTS9-AS2, as shown by increasing concentrations and prolonged treatment with TMZ. RNA pull-down and RIP assays indicated that both endogenous and exogenous ADAMTS9-AS2 directly binds to the RRM and Znf_RanBP2 domains of FUS, consequently increasing FUS protein expression. Knockdown of ADAMTS9-AS2 reduced the half-life of FUS and decreased FUS protein stability via K48 ubiquitin degradation. Moreover, the E3 ubiquitin-protein ligase MDM2 interacts with and down regulates FUS, while the RRM and Znf_RanBP2 domains of FUS facilitate its binding with MDM2. ADAMTS9-AS2 decreased the interaction between MDM2 and FUS, which mediates FUS K48 ubiquitination. Additionally, knockdown of the ADAMTS9-AS2/FUS signaling axis significantly alleviated progression and metastasis in TMZ-resistant cells.ConclusionADAMTS9-AS2 possessed a novel function that promotes TMZ resistance via upregulating the FUS/MDM2 axis in GBM cells. The RRM or Znf_RanBP2 domains of FUS facilitate the combination of ADAMTS9-AS2 and FUS, competitively inhibiting MDM2-dependent FUS K48 ubiquitination and resulting in enhanced FUS stability and TMZ resistance. Our results suggest that the ADAMTS9-AS2/FUS/MDM2 axis may represent a suitable prognostic biomarker and a potential target in TMZ-resistant GBM therapy.

Breast cancer is the most common malignancy among women, with the highest incidence rate worldwide. Dysregulation of long noncoding RNAs during the preliminary stages of breast carcinogenesis is poorly understood. In this study, we performed RNA sequencing to identify long noncoding RNA expression profiles associated with early‐stage breast cancer. RNA sequencing was performed on six invasive ductal carcinoma (IDC) tissues along with paired normal tissue samples, seven ductal carcinoma in situ tissues, and five apparently normal breast tissues. We identified 375 differentially expressed lncRNAs (DElncRNAs) in IDC tissues compared to paired normal tissues. Antisense transcripts (~ 58%) were the largest subtype among DElncRNAs. About 20% of the 375 DElncRNAs were supported by typical split readings leveraging their detection confidence. Validation was performed in n = 52 IDC and paired normal tissue by qRT‐PCR for the identified targets (ADAMTS9‐AS2, EPB41L4A‐AS1, WDFY3‐AS2, RP11‐295M3.4, RP11‐161M6.2, RP11‐490M8.1, CTB‐92J24.3, and FAM83H‐AS1). We evaluated the prognostic significance of DElncRNAs based on TCGA datasets and report that overexpression of FAM83H‐AS1 was associated with patient poor survival. We confirmed that the downregulation of ADAMTS9‐AS2 in breast cancer was due to promoter hypermethylation through in vitro silencing experiments and pyrosequencing. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim of this study was to elucidate the regulatory effect of long non-coding RNA (lncRNA) ADAMTS9-AS2 on Tamoxifen (TAM) resistance in breast cancer (BC), and to explore its underlying mechanism. PATIENTS AND METHODS: TAM-resistant BC cell lines were first verified. Subsequently, cell proliferation and apoptosis were detected using cell counting kit-8 (CCK-8), 5-ethynyl-2’-deoxyuridine (EdU) assay and flow cytometry, respectively. Protein levels of ABCB1, ABCC1, and ABCG2 in TAM-treated MCF-7 and MCF-7R cells were determined by Western blot. ADAMTS9-AS2 expression in BC tissues, para-cancerous tissues, as well as MCF-7 and MCF-7R cells, was accessed by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between ADAMTS9-AS2 expression with pathological grade and tumor size of BC was explored. Chromatin fractionation was conducted to elucidate the subcellular distribution of ADAMTS9-AS2. The binding condition between ADAMTS9-AS2 and microRNA-130a-5p, as well as microRNA-130a-5p and PTEN, was verified by the dual-luciferase reporter gene assay. Furthermore, regulatory effects of ADAMTS9-AS2, microRNA-130a-5p, and PTEN on the proliferation and apoptosis of MCF-7R cells were determined. RESULTS: MCF-7R cells were identified with TAM resistance. ADAMTS9-AS2 was lowly expressed in BC tissues and MCF-7R cells. Particularly, ADAMTS9-AS2 expression in BC tissues with grade III-IV or tumor size ≥2 cm was significantly lower than that of controls. Dual-luciferase reporter gene assay confirmed the binding condition between ADAMTS9-AS2 and microRNA- 130a-5p, showing a negative correlation indicated by Pearson correlation analysis. PTEN was positively correlated with ADAMTS9-AS2. Overexpression of ADAMTS9-AS2 reversed the increased viability and decreased apoptosis induced by microRNA-130a-5p mimics transfection. In addition, PTEN knockdown reversed the decreased viability and accelerated apoptosis caused by ADAMTS9-AS2 overexpression. CONCLUSIONS: We found that ADAMTS9-AS2 is lowly expressed in BC tissues and drug-resistant BC cells. Low expression of ADAMTS9-AS2 inhibits PTEN expression and enhances tamoxifen resistance through targeting microRNA-130a-5p. [ABSTRACT FROM AUTHOR]

Abstract Increasing studies revealed that aberrant expression of long non-coding RNAs (lncRNAs) play critical roles in ovarian cancer (OC) progression. However, the roles and underlying mechanisms of ADAMTS9-AS2 in OC remain unclear. In the present study, we showed that ADAMTS9-AS2 expression was significantly decreased in OC tissues and cell lines. Low ADAMTS9-AS2 expression was correlated with advanced FIGO stage, lymph-node metastasis, and poor overall survival of OC patients. Function assays showed that ADAMTS9-AS2 reduced OC cells proliferation, invasion, and epithelial-mesenchymal transition (EMT) processes in vitro and restrained tumor growth in vivo. The underlying mechanism studies indicated that ADAMTS9-AS2 functioned as a competing endogenous RNA (ceRNA) for miR-182-5p to promote cell proliferation and invasion. In addition, we revealed that FOXF2 acted as a direct target of miR-182-5p and mediated the effects of ADAMTS9-AS2 on OC cells progression. Taken together, our data suggested that lncRNA ADAMTS9-AS2 decreased OC progression by regulating miR-182-5p/FOXF2 axis, indicating ADAMTS9-AS2 could serve as a potential therapeutic target for OC treatment. [ABSTRACT FROM AUTHOR]

Recent decade has seen a tremendous progress in identification of the role of different long non-coding RNAs (lncRNAs) in human pathologies. ADAMTS9-AS2 is an example of lncRNAs with different roles in human disorders. It is mostly acknowledged as a tumor suppressor lncRNA in different types of cancers. However, it has been reported to be up-regulated in tongue squamous cell carcinoma, salivary adenoid cystic carcinoma and glioblastoma. Moreover, ADAMTS9-AS2 is possibly involved in the pathoetiology of pulpitis, acute ischemic stroke, type 2 diabetes and its complications. This lncRNA sponges miR-196b-5p, miR-223–3p, miR-130a-5p, miR-600, miR-223–3p, miR-27a-3p, miR-32, miR-143–3p, miR-143–3p and miR-182–5p in order to regulate downstream mRNAs. This review aims at summarization of the role of ADAMTS9-AS2 in different disorders with a particular focus on its diagnostic and prognostic values. [ABSTRACT FROM AUTHOR]

Melittin (MEL) has been reported to exhibit anti-cancer effects in vitro against several types of cancer. Long non-coding RNA (lncRNA) ADAMTS9-AS2 can be used as a tumor suppressor. However, there is insufficient data on the potential link between MEL and ADAMTS9-AS2 in hepatocellular carcinoma (HCC). RT-qPCR, CCK-8, colony formation, scratch wound healing and transwell assays were used to detect the function of MEL or ADAMTS9-AS2 on HCC cells. Furthermore, Western blot analysis was applied to determine that whether an association existed in MEL or ADAMTS9-AS2 with the PI3K/AKT/mTOR signal pathway. In addition, RT-qPCR and Western blot analysis validated that whether MEL has a demethylation effect. All the experimental data showed that MEL or ADAMTS9-AS2 inhibited the proliferation, migration and invasion of MHCC97-H and HepG2 cells, which may relate to PI3K/AKT/mTOR signal pathway. Moreover, the result showed that MEL treatment inhibited the expression of DNA methyltransferase protein-1 (DNMT1), which acted as the role of demethylation, and then up-regulated the expression of ADAMTS9-AS2, affecting the development of HCC. ADAMTS9-AS2 played a role in MEL-induced HCC inhibition. This study provided an interesting theoretical basis and further evidence for the potential application of MEL in the treatment of HCC. [Display omitted] • Melittin up-regulates ADAMTS9-AS2 to inhibit the progression of HCC. • Providing evidence for the potential application of MEL in the treatment of HCC. • MEL or ADAMTS9-AS2 inhibited the progression of HCC via PI3K/AKT/mTOR signal pathway. [ABSTRACT FROM AUTHOR]

Growing number of long noncoding RNAs (lncRNAs) are emerging as new modulators in cancer origination and progression. A lncRNA, ADAM metallopeptidase with thrombospondin type 1 motif, 9 (ADAMTS9) antisense RNA 2 (ADAMTS9-AS2), with unknown function, is the antisense transcript of tumor suppressor ADAMTS9. In the present study, we investigated the expression pattern and functional role of ADAMTS9-AS2 in glioma by using real-time PCR and gain-/loss-of-function studies. The results showed that the ADAMTS9-AS2 expression was significantly downregulated in tumor tissues compared with normal tissues and reversely associated with tumor grade and prognosis. Multivariate analysis of the prognosis factors showed that low ADAMTS9-AS2 expression was a significant independent predictor of poor survival in glioma. Overexpression of ADAMTS9-AS2 resulted in significant inhibition of cell migration in glioma, whereas knockdown of ADAMTS9-AS2 showed the opposite effect. We also found that ADAMTS9-AS2 expression was negatively correlated with DNA methyltransferase-1 (DNMT1). In addition, DNMT1 knockdown led to remarkable enhancement of ADAMTS9-AS2 expression. By 5-aza-dC treatment, the ADAMTS9-AS2 expression was also reactivated. The results suggested that ADAMTS9-AS2 is a novel tumor suppressor modulated by DNMT1 in glioma. LncRNA ADAMTS9-AS2 may serve as a potential biomarker and therapeutic target for glioma. [ABSTRACT FROM AUTHOR]

Background: Long non-coding RNAs (lncRNA) have been identified as novel molecular regulators in cancers. LncRNA ADAMTS9-AS2 can mediate the occurrence and development of cancer through various ways, such as regulating miRNAs, activating the classical signaling pathways in cancer, and so on, which have been studied by many scholars. In this review, we summarize the molecular mechanisms of ADAMTS9-AS2 in different human cancers., Methods: Through a systematic search of PubMed, lncRNA ADAMTS9-AS2 mediated molecular mechanisms in cancer are summarized inductively., Results: ADAMTS9-AS2 aberrantly expression in different cancers is closely related to cancer proliferation, invasion, migration, and inhibition of apoptosis. The involvement of ADAMTS9-AS2 in DNA methylation, mediating PI3K / Akt / mTOR signaling pathways, and regulating miRNAs and proteins, shows its significant potential as a therapeutic cancer target., Conclusion: LncRNA ADAMTS9-AS2 can become a promising biomolecular marker and a therapeutic target for human cancer., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Graphical abstract Highlights • ADAMTS9-AS2 remarkedly increases in TSCC, especially in TSCC samples with lymphnode metastasis. • ADAMTS9-AS2 expression correlates with the clinical importance and poor prognosis in TSCC. • ADAMTS9-AS2 konckdown inhibits TSCC cell proliferation, migration and invasion. • ADAMTS9-AS2 promotes TSCC metastasis and proliferation via miR-600/EZH2 axis. Abstract Long noncoding RNAs (lncRNAs) are a type of noncoding RNA transcript that are characterized by lack of protein-coding capacity. The vital role of lncRNAs in tongue squamous cell carcinoma (TSCC) is attracting increasing attention. In the present study, we identify a key lncRNA regulating TSCC metastasis and investigated the underlying mechanism. Our results indicate that the lncRNA ADAMTS9-AS2 is most significantly upregulated in TSCC tissues from patients with lymph node metastasis and is closely associated with poor prognosis. Furthermore, ADAMTS9-AS2 knockdown in TSCC cells leads to a inhibition of cell migration and invasion and reverses TGF-β1 induced EMT. ADAMTS9-AS2 knockdown also inhibits TSCC cell growth in vitro and in vivo. In addition, we show that ADAMTS9-AS2 is a cytoplasmic lncRNA that shares the miRNA response elements (MREs) of miR-600 with EZH2, which is confirmed by a luciferase reporter assay and AGO2-dependent RNA immunoprecipitation (RIP). In summary, our results demonstrate an explicit oncogenic role of ADAMTS9-AS2 in TSCC tumorigenesis via competition with miR-600, suggesting a new regulatory mechanism of ADAMTS9-AS2 and providing a potential therapeutic target for TSCC patients. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) have been implicated in the biology of esophageal cancer via mRNA degradation or translational inhibition. CDH3 is also aberrantly expressed in numerous cancers. This study was conducted with the hypothesis that ADAMTS9-AS2 or CDH3 methylation plays a role in esophageal cancer cell activity and in vivo development. Firstly, mRNA levels of ADAMTS9-AS2 and CDH3 in esophageal cancer tissues and cells were detected by reverse-transcription quantitative polymerase chain reaction. Afterward, esophageal cancer OE21 cells were treated with overexpression of ADAMTS9-AS2, siRNA against ADAMTS9-AS2, overexpression of CDH3 and demethylating agent 5-aza-dc. The biological functions of esophageal cancer OE21 cells were assayed to define the regulatory mechanisms of ADAMTS9-AS2 in esophageal cancer. The interactions among ADAMTS9-AS2, DNMT1/DNMT3 (A/B) and CDH3 were detected by MSP, RNA pull-down, RIP, and ChIP assays. The in vitro findings were reproduced in nude mice to explore the role of ADAMTS9-AS2 in the development of esophageal cancer in vivo. Esophageal cancers expressed low levels of ADAMTS9-AS2 and high levels of CDH3. Methylation of CDH3 promoter was induced by ADAMTS9-AS2 via DNMT1/DNMT3 (A/B). Furthermore, proliferation, invasion, and migration of esophageal cancer cells were inhibited by ADAMTS9-AS2 via downregulation of CDH3. Suppressed esophageal cancer development in vivo was also detected after ADAMTS9-AS2 overexpression. Overexpressed ADAMTS9-AS2 aids in the suppression of esophageal cancer development, which is achieved via inducing CDH3 promoter methylation., (© 2019 Wiley Periodicals, Inc.)

Accumulating evidence reveals the principal role of long noncoding RNAs in the progression of clear cell renal cell carcinoma (ccRCC). However, little is known about the underlying mechanism of ADAM metallopeptidase with thrombospondin type 1 motif, 9 antisense RNA 2 (ADAMTS9-AS2) in ccRCC. Here, bioinformatics analyses verified ADAMTS9-AS2 is a long noncoding RNA and its high expression was associated with better prognosis of ccRCC. ADAMTS9-AS2 was clearly downregulated in ccRCC clinical samples and cell lines. Clinical data showed low-expressed ADAMTS9-AS2 was correlated with worse overall survival in ccRCC patients. Next, miR-27a-3p was identified as an inhibitory target of ADAMTS9-AS2 by dual-luciferase reporter and RNA immunoprecipitation assays. Both overexpressed ADAMTS9-AS2 and underexpressed miR-27a-3p in ccRCC cell lines led to the inhibition of cell proliferation and the reduction of chemoresistance. Additionally, Forkhead Box Protein O1 (FOXO1) was confirmed as the inhibitory target of miR-27a-3p. Induced by ADAMTS9-AS2 overexpression, cell proliferation and chemoresistance exhibited an obvious reduction, FOXO1 expression showed an evident increase, but all were reversed after miR-27a-3p was simultaneously overexpressed. Collectively, these results suggest ADAMTS9-AS2 inhibits the progression and impairs the chemoresistance of ccRCC via miR-27a-3p-mediated regulation of FOXO1 and may serve as a prognostic biomarker and therapeutic target for ccRCC.

Neurotropic infiltrative growth and distant metastasis are the main causes of death in salivary adenoid cystic carcinoma (SACC) patients. Long noncoding RNAs (lncRNAs) are involved in many human neoplasms, however, their potential roles in SACC are unclear. In our study, we found that ADAM metallopeptidase with thrombospondin type 1 motif, 9 (ADAMTS9) antisense RNA 2 (ADAMTS9-AS2) was significantly upregulated in SACC patients with metastasis and SACC-lung metastasis (LM) cells. Moreover, ADAMTS9-AS2 expression was closely associated with the prognosis and distant metastasis in SACC patients. Next, we found that c-myc could specifically bind to the promoter of ADAMTS9-AS2 and activated its transcription. Knockdown of ADAMTS9-AS2 significantly inhibited migration and invasion of SACC cells in vitro and distant lung metastasis in vivo. Furthermore, ADAMTS9-AS2, which mainly expressed in the cytoplasm, shared microRNA (miRNA) response elements with Integrin α6 (ITGA6). Overexpression of ADAMTS9-AS2 competitively bound to miR-143-3p that inhibited ITGA6 from miRNA-mediated degradation, and thus it activated the activity of PI3K/Akt and MEK/Erk signaling and facilitated SACC metastasis. In summary, ADAMTS9-AS2 promotes migration and invasion in SACC by competing with miR-143-3p. This sheds a new insight into the regulation mechanism of ADAMTS9-AS2, and it provides a possible application for the SACC treatment., (Copyright © 2018 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.)