Long noncoding RNA SBF2-AS1 contributes to the growth and metastatic phenotypes of NSCLC via regulating miR-338-3p/ADAM17 axis.
ABSTRACT: Non-small cell lung cancer (NSCLC) is a type of refractory malignant lung cancer with a high rate of metastasis and mortality. Currently, long non-coding RNA (lncRNA) SBF2 Antisense RNA 1 (SBF2-AS1) is considered as a biomarker for a variety of tumors. However, the function of SBF2-AS1 in the growth and metastasis of NSCLC needs to be further studied. In this study, we revealed that SBF2-AS1 was overexpressed in NSCLC tissues compared with that in normal tissues. SBF2-AS1 silencing restrained the growth and aggressive phenotypes of NSCLC cell in vitro. Consistently, SBF2-AS1 knockdown hindered the growth of NSCLC cell in nude mice. The following luciferase reporter gene assay and RNA immunoprecipitation (RIP) assay suggested the relationship between miR-338-3p and SBF2-AS1. The rescue experiments showed that miR-338-3p inhibitor abolished SBF2-AS1 silencing caused inhibition on the growth, migration and invasiveness of NSCLC cell. The luciferase reporter assay and immunoblotting assay validated that A Disintegrin and Metalloprotease 17 (ADAM17) was a target of miR-338-3p. In addition, SBF2-AS1 positively regulated the level of ADAM17 through sponging for miR-338-3p. Finally, we revealed that SBF2-AS1 contributed to the proliferation and metastatic phenotypes of NSCLC cell via regulating miR-338-3p/ADAM17 axis.
Project description:Glioblastoma (GBM) is the most aggressive primary intracranial tumor of adults and confers a poor prognosis due to high vascularization. Hence anti-angiogenic therapy has become a promising strategy for GBM treatment. In this study, the transcription factor nuclear factor of activated T-cells 5 (NFAT5) was significantly elevated in glioma samples and GBM cell lines, and positively correlated with glioma WHO grades. Knockdown of NFAT5 inhibited GBM cell-driven angiogenesis. Furthermore, long non-coding RNA SBF2 antisense RNA 1 (SBF2-AS1) was upregulated in glioma samples and knockdown of SBF2-AS1 impaired GBM-induced angiogenesis. Downregulation of NFAT5 decreased SBF2-AS1 expression at transcriptional level. In addition, knockdown of SBF2-AS1 repressed GBM cell-driven angiogenesis via enhancing the inhibitory effect of miR-338-3p on EGF like domain multiple 7 (EGFL7). In vivo study demonstrated that the combination of NFAT5 knockdown and SBF2-AS1 knockdown produced the smallest xenograft volume and the lowest microvessel density. NFAT5/SBF2-AS1/miR-338-3p/EGFL7 pathway may provide novel targets for glioma anti-angiogenic treatment.
Project description:Background and aims:Studies show that the long non-coding RNA, SBF2-AS1, plays a critical role in cancer progression, but the role of SBF2-AS1 in gastric cancer has not been reported. Therefore, this study aimed to elucidate the mechanism of SBF2-AS1 in gastric cancer (GC). Methods:A meta-analysis, based on the gene expression omnibus database and TCGA dataset was performed to explore the prognostic value of SBF2-AS1 in GC. RT-PCR was also conducted to investigate the clinicopathologic value of SBF2-AS1 in GC. The effect of SBF2-AS1 in GC cell lines was conducted by gain or loss-of-function assays, and the SBF2-AS1 target gene was confirmed using a luciferase reporter assay and bioinformatics. Results:SBF2-AS1 was overexpressed in GC tissues and cell lines, and SBF2-AS1 overexpression indicated poor overall survival and could serve as an independent prognostic factor. Moreover, knockdown of SBF2-AS1 inhibited cell growth, invasion, and metastasis, promoted apoptosis, and caused cell cycle arrest. Luciferase reporter and gain- or loss-of-function assays indicated that SBF2-AS1 acted as a competing endogenous (ceRNA) for microRNA (miR)-302b-3p, which blocked the inhibitory effect of miR-302b-3p on the E2F transcription factor 3 (E2F3). Conclusion:SBF2-AS1 could be a potential diagnostic and prognostic biomarker in GC, and SBF2-AS1 accelerates tumor progression via the miR-302b-3p/E2F3 axis.
Project description:Long noncoding RNA (lncRNA) play important roles in the pathogenesis of cancer. LncRNA SBF2-AS1is unregulated in lung cancer tissues, while its biological function and molecular mechanism are largely unknown. RNA sequencing results suggest cell cycle-related genes are altered after SBF2-AS1 knockdown. In vivo and in vitro experiments confirm SBF2-AS1 could promote tumorigenesis of lung cancer. Further experiments prove SBF2-AS1 could bind with miR-338-3p and miR-362-3p to regulate various cell cycle-related genes, including E2F1. These results indicate the existence of ceRNA network driven by SBF2-AS1 through sponging miRNAs. Overall design: A549 cells are plated into 6-well plate and then transfected small interfering RNA (siRNA) specifically targeting SBF2-AS1 or negative control (NC) siRNA. 24 hours after transfection, cells are harvested and extract total RNA with TRIZol reagent.
Project description:Recent evidence has proven that long noncoding RNAs (lncRNAs) play important roles in cancer biology, while few lncRNAs have been characterized in NSCLC. Here, we characterized a novel lncRNA, SBF2 antisense RNA 1 (SBF2-AS1), in non-small cell lung cancer (NSCLC).Quantitative real-time PCR was used to quantify SBF2-AS1 expression in NSCLC tissues and cell lines. The correlation of SBF2-AS1 expression with clinicopathologic features was analyzed in a cohort NSCLC patient. Loss of function and gain of function studies were performed to determine the effects of SBF2-AS1 on proliferation and metastasis of NSCLC cells. RNA immunoprecipitation and chromosome immunoprecipitation assay was performed to confirm the interaction between SBF2-AS1 with protein and chromosome.We confirmed that SBF2-AS1 was significantly upregulated in NSCLC compared with corresponding non-tumor tissues, and a high expression level of SBF2-AS1 was correlated with lymph node metastasis and advanced TNM stage. Using siRNAs specifically targeting SBF2-AS1 and plasmid vector, we successfully silenced and overexpressed SBF2-AS1 in NSCCLC cell lines and investigated its biological function both in vitro and in vivo. After the silencing of SBF2-AS1, the metastasis of NSCLC cells was significantly inhibited, the silencing of SBF2-AS1 decreased the proliferation of NSCLC cells, and the cell cycle was arrested at the G1 phase; while overexpression promoted proliferation ability. Xenograft tumor models revealed that the silencing of SBF2-AS1 inhibited tumor growth in vivo. We speculated that SBF2-AS1 might negatively regulate P21. RNA immunoprecipitation discovered that SBF2-AS2 could bind with a core component of polycomb repressive complex2, SUZ12. Additionally chromatin immunoprecipitation assay demonstrated that, after silencing SBF2-AS1, the enrichment of SUZ12 and trimethylation of histone 3 lysine 27 decreased at the promoter region of P21.We demonstrated that SBF2-AS1 is upregulated in NSCLC and promotes proliferation of NSCLC tumor cells. SBF2-AS1 may serve as a novel biomarker and potential therapeutic target for NSCLC patients.
Project description:Objective: This study is implemented to probe into the function of lncRNA SBF2-AS1 as a competing endogenous RNA (ceRNA) to sponge microRNA-142-3p (miR-142-3p) in modulating TWF1 expression in the gemcitabine resistance of pancreatic cancer. Results: LncRNA SBF2-AS1 was highly expressed in pancreatic cancer tissues and cells. SBF2-AS1 was found to be associated with gemcitabine resistance in pancreatic cancer. Knock-down of SBF2-AS1 inhibited proliferation, epithelial-mesenchymal transition, while promoting apoptosis of gemcitabine resistant pancreatic cancer cells. SBF2-AS1 inhibited the expression of TWF1 by competitively binding with miR-142-3p in pancreatic cancer. Conclusion: Our study demonstrates that knock-down of SBF2-AS1 inhibits the expression of TWF1 by competitively binding with miR-142-3p to induce gemcitabine resistance in pancreatic cancer. Methods: Expression of SBF2-AS1 was tested in pancreatic cancer tissues and cells. Construction of AsPC-1/GEM and PANC-1/GEM cells with low expression of SBF2-AS1 was performed to determine the biological behaviors of drug-resistant cells. AsPC-1 and PANC-1 cells expressing SBF2-AS1 and/or miR-142-3p were constructed and treated with different concentrations of gemcitabine to detect the sensitivity of the cells to gemcitabine. The binding relationship between SBF2-AS1 and miR-142-3p and between miR-142-3p and TWF1 were determined.
Project description:BACKGROUND:Acquired drug resistance is a constraining factor in clinical treatment of glioblastoma (GBM). However, the mechanisms of chemoresponsive tumors acquire therapeutic resistance remain poorly understood. Here, we aim to investigate whether temozolomide (TMZ) resistance of chemoresponsive GBM was enhanced by long non-coding RNA SBF2 antisense RNA 1 (lncRNA SBF2-AS1) enriched exosomes. METHOD:LncSBF2-AS1 level in TMZ-resistance or TMZ-sensitive GBM tissues and cells were analyzed by qRT-PCR and FISH assays. A series of in vitro assay and xenograft tumor models were performed to observe the effect of lncSBF2-AS1 on TMZ-resistance in GBM. CHIP assay were used to investigate the correlation of SBF2-AS1 and transcription factor zinc finger E-box binding homeobox 1 (ZEB1). Dual-luciferase reporter, RNA immunoprecipitation (RIP), immunofluorescence and western blotting were performed to verify the relation between lncSBF2-AS1, miR-151a-3p and XRCC4. Comet assay and immunoblotting were performed to expound the effect of lncSBF2-AS1 on DNA double-stand break (DSB) repair. A series of in vitro assay and intracranial xenografts tumor model were used to determined the function of exosomal lncSBF2-AS1. RESULT:It was found that SBF2-AS1 was upregulated in TMZ-resistant GBM cells and tissues, and overexpression of SBF2-AS1 led to the promotion of TMZ resistance, whereas its inhibition sensitized resistant GBM cells to TMZ. Transcription factor ZEB1 was found to directly bind to the SBF2-AS1 promoter region to regulate SBF2-AS1 level and affected TMZ resistance in GBM cells. SBF2-AS1 functions as a ceRNA for miR-151a-3p, leading to the disinhibition of its endogenous target, X-ray repair cross complementing 4 (XRCC4), which enhances DSB repair in GBM cells. Exosomes selected from temozolomide-resistant GBM cells had high levels of SBF2-AS1 and spread TMZ resistance to chemoresponsive GBM cells. Clinically, high levels of lncSBF2-AS1 in serum exosomes were associated with poor response to TMZ treatment in GBM patients. CONCLUSION:We can conclude that GBM cells remodel the tumor microenvironment to promote tumor chemotherapy-resistance by secreting the oncogenic lncSBF2-AS1-enriched exosomes. Thus, exosomal lncSBF2-AS1 in human serum may serve as a possible diagnostic marker for therapy-refractory GBM.
Project description:Evidence has indicated that M2 macrophages promote the progression of cancers, but few focus on the ability of M2 macrophage-derived exosomes in pancreatic cancer (PC). This study aims to explore how M2 macrophages affect malignant phenotypes of PC through regulating long non-coding RNA SET-binding factor 2 antisense RNA 1 (lncRNA SBF2-AS1)/microRNA-122-5p (miR-122-5p)/X-linked inhibitor of apoptosis protein (XIAP) axis. THP-1 cells were transformed into M1 macrophages by lipopolysaccharide and interferon-? treatment, and into M2 macrophages after interleukin-4 treatment. The PANC-1 PC cell line with the largest lncRNA SBF2-AS1 expression was selected, and M2 macrophage-derived exosomes were isolated and identified. A number of assays were applied for the examination of lncRNA SBF2-AS1 expression, PC cell biological functions and subcellular localization of lncRNA SBF2-AS1. XIAP expression was detected, along with the interaction among lncRNA SBF2-AS1, miR-122-5p and XIAP. M2 macrophage exosomal lncRNA SBF2-AS1 expression's effects on the tumorigenic ability of PANC-1 cells in nude mice were also investigated. M2 macrophage-derived exosomes promoted progression of PC cells. Overexpressed lncRNA SBF2-AS1 promoted progression of PC cells. LncRNA SBF2-AS1 was found to act as a competing endogenous RNA to repress miR-122-5p and up-regulate XIAP. Constrained lncRNA SBF2-AS1 in M2 macrophage-derived exosomes contributed to restraining tumorigenic ability of PC cells. Collectively, our study reveals that constrained lncRNA SBF2-AS1 in M2 macrophage-derived exosomes increases miR-122-5p expression to restrain XIAP expression, which further inhibits PC progression.
Project description:Objective:Long noncoding RNA (LncRNA) SBF2-AS1 was reportedly to function as an oncogene in several types of cancers, such as hepatocellular carcinoma, nonsmall cell lung cancer, glioma, and colorectal cancer. However, the biological roles and regulatory mechanisms of SBF2-AS1 in gastric cancer (GC) are unknown. Methods:The expression of SBF2-AS1 and miR-545 were examined in GC tissues and cell lines via real-time quantitative PCR. The relationship of SBF2-AS1 with miR-545 was verified via dual-luciferase reporter gene assay and RNA immunoprecipitation. The influences of SBF2-AS1 on cell proliferation, migration, and invasion were determined using cell counting Kit-8 (CCK-8), wound healing, and transwell invasion assays, respectively. Results:LncRNA SBF2-AS1 expression was upregulated in GC tissues, especially in advanced clinical stage cases. Moreover, increased SBF2-AS1 indicated a poor survival rate. Functionally, the downregulation of SBF2-AS1 by siRNA in GC cells suppressed the proliferation, migration, and invasion. In terms of mechanism, SBF2-AS1 can directly bind to miR-545 and regulate its expression. Moreover, SBF2-AS1 knockdown significantly decreased the expression of EMS1, which was the direct target of miR-545. Importantly, inhibition of miR-545 or overexpression of EMS1 partially reversed SBF2-AS1-depletion-caused suppression on proliferation, migration, and invasion. Conclusion:These findings elucidated a crucial role of SBF2-AS1 as a miR-545 sponge in GC cells, suggesting that SBF2-AS1 might be a potential target for GC.
Project description:PSMA3 antisense RNA 1 (PSMA3?AS1), a long noncoding RNA, promotes the progression of esophageal squamous cell carcinoma. However, no study to date has explored the expression or roles of PSMA3?AS1 in non?small cell lung carcinoma (NSCLC). The present study examined the expression profile and role of PSMA3?AS1 in NSCLC. It also aimed to identify how PSMA3?AS1 promotes the malignant phenotype of NSCLC cells. PSMA3?AS1 expression in NSCLC tissues and cell lines was measured by reverse transcription?quantitative polymerase chain reaction. Cell Counting Kit?8, cell apoptosis, Transwell migration and invasion, and xenograft tumor assays were conducted to study the effects of PSMA3?AS1 on the aggressive phenotype of NSCLC cells. Furthermore, bioinformatics analysis, RNA immunoprecipitation, luciferase reporter assay, western blotting, and rescue experiments were used to elucidate the interaction among PSMA3?AS1, microRNA?409?3p (miR?409?3p), and spindlin 1 (SPIN1) in NSCLC cells. In the present study, high levels of PSMA3?AS1 were confirmed in both NSCLC tissues and cell lines. An increased PSMA3?AS1 level was correlated with advanced tumor?node?metastasis stage and increased lymph node metastasis. Patients with NSCLC with high PSMA3?AS1 levels had shorter overall survival than those with low PSMA3?AS1 levels. PSMA3?AS1 depletion significantly decreased NSCLC cell proliferation, migration, and invasion, as well as substantially increased cell apoptosis in vitro. Furthermore, PSMA3?AS1 deficiency decreased NSCLC tumor growth in vivo. Through molecular mechanism assays, it was revealed that PSMA3?AS1 acted as a molecular sponge for miR?409?3p and consequently increased SPIN1 expression. Notably, rescue experiments revealed that the inhibition of miR?409?3p or restoration of SPIN1 expression abrogated the effects of PSMA3?AS1 knockdown in NSCLC cells. Collectively, PSMA3?AS1 functioned as an oncogenic long noncoding RNA in NSCLC. PSMA3?AS1 sponged miR?409?3p and thus increased SPIN1 expression, promoting the aggressive phenotype of NSCLC cells.
Project description:Objective:Our present study aimed to further investigate the molecular basis of long non-coding RNA homeobox A11 antisense (HOXA11-AS) in the tumorigenesis of non-small cell lung cancer (NSCLC). Methods:HOXA11-AS, microRNA-148a-3p (miR-148a-3p), and DNA methyltransferase 1 (DNMT1) mRNA levels were measured by RT-qPCR assay. DNMT1 protein level was determined by Western blot assay. Cell proliferative capacity and apoptotic rate were determined by CCK-8 assay and flow cytometry analysis, respectively. The relationships of HOXA11-AS, miR-148a-3p, and DNMT1 were tested through bioinformatics analysis, luciferase assay, and RNA pull down assay. Mouse xenograft models of NSCLC were established to examine the biological function of HOXA11-AS in vivo. Results:HOXA11-AS expression was notably upregulated and miR-148a-3p expression was conspicuously downregulated in NSCLC tissues and cells. HOXA11-AS knockdown curbed NSCLC cell proliferation and promoted cell apoptosis through directly increasing miR-148a-3p expression. Moreover, miR-148a-3p overexpression suppressed NSCLC cell proliferation and induced cell apoptosis. HOXA11-AS functioned as a competing endogenous RNA (ceRNA) of miR-148a-3p to increase DNMT1 expression in NSCLC cells. And, DNMT1 upregulation weakened the influence of HOXA11-AS1 loss on NSCLC cell proliferation and apoptosis. Additionally, HOXA11-AS knockdown suppressed NSCLC xenograft growth by upregulating miR-148a-3p and downregulating DNMT1 in vivo. Conclusion:HOXA11-AS facilitated NSCLC tumorigenesis through miR-148a-3p/DNMT1 axis in vitro and in vivo, deepening our understanding of the molecular basis of HOXA11-AS in the development of NSCLC.