SBF2-AS1 Expression Research Articles

Low expression of lncRNA SBF2-AS1 regulates the miR-302b-3p/TGFBR2 axis, promoting metastasis in laryngeal cancer.

The 5-year survival rate of laryngeal cancer continues to decline, and the laryngeal particularity of the anatomy adversely affects the patient's quality of life. Emerging evidence suggests that long noncoding RNAs (lncRNAs) are closely correlated to key steps in the malignant progression of cancer cells. In this study, we report the role of lncRNA SBF2-AS1/miR-302b-3p/TGFBR2 interactions in the metastasis of laryngeal squamous cell carcinoma (LSCC). We verified that SBF2-AS1 was significantly downregulated in LSCC tissues and cell lines using qRT-PCR analysis. Its low expression was correlated to lymph node metastasis and an advanced clinical stage. More importantly, LSCC patients with low expression of SBF2-AS1 tended to have a poor prognosis. Based on this, we performed gain-of-function and loss-of-function experiments in LSCC cell lines. The results confirmed that knocking down SBF2-AS1 can promote the metastasis of LSCC cells and enhance epithelial-mesenchymal transition phenotype, while the upregulation of SBF2-AS1 expression resulted in the opposite. Our in vivo model verified that SBF2-AS1 overexpression could inhibit LSCC cell metastasis. Subsequent mechanistic studies revealed that SBF2-AS1 acted as a competing endogenous RNA that upregulated the expression of TGFBR2 by endogenous sponging for miR-302b-3p in LSCC cell lines. Moreover, miR-302b-3p overexpression reversed the inhibitory effects on LSCC metastasis induced by upregulation of SBF2-AS1 expression, and inhibition of TGFBR2 expression reversed the effect of SBF2-AS1 on metastasis. Our study proposes SBF2-AS1 as a biomarker to predict the prognosis of LSCC patients and a novel potential therapeutic target.

The molecular mechanisms of the long noncoding RNA SBF2-AS1 in regulating the proliferation of oesophageal squamous cell carcinoma

The long noncoding RNASBF2-AS1 can promote the occurrence and development of many kinds of tumours, but its role in oesophageal squamous cell carcinoma (ESCC) is unknown. We found that SBF2-AS1 was up-regulated in ESCC, and its expression was positively correlated with tumor size (P = 0.0001), but was not related to gender, age, TNM stage, histological grade, and lymphnode metastasis (P > 0.05). It was further found that the higher the expression of SBF2-AS1, the lower the survival rate. COX multivariate analysis showed that the expression of SBF2-AS1 was an independent prognostic factor. Functional experiments show that inhibition of SBF2-AS1 can inhibit the proliferation of ESCC through in vivo and in vitro, and overexpression of SBF2-AS1 can promote the proliferation of ESCC and inhibit its apoptosis. In mechanism, SBF2-AS1/miR-338-3P, miR-362-3P/E2F1 axis are involved in the regulation of ESCC growth. In general, SBF2-AS1 may be used as ceRNA to combine with miR-338-3P and miR-362-3P to up-regulate the expression ofE2F1, and ultimately play a role in promoting cancer. It may be used as a therapeutic target and a biomarker for prognosis.

The Clinical Prognostic Value of lncRNA SBF2-AS1 in Cancer Patients: A Meta-Analysis.

Background:The mortality and recurrence of patients with cancer is of high prevalence. SET-binding factor 2 (SBF2) antisense RNA1 (lncRNA-SBF2-AS1) is a promising long non-coding RNA. There is increasing evidence that SBF2-AS1 is abnormally expressed in various tumors and is associated with cancer prognosis. However, the identification of the effect of lncRNA SBF2-AS1 in tumors remains necessary.Materials and Methods:Up to November 2, 2020, electronic databases, including PubMed, Cochrane Library, EMBASE, Medline, and Web of Science, were searched. The results were evaluated by pooled odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs).Results:A total of 11 literatures on cancer patients were included for the present meta-analysis. The combined results revealed that high expression of SBF2-AS1 was significantly associated with unfavorable overall survival (OS) (HR = 1.48, 95% CI: 1.34-1.62, P < 0.00001) in a variety of cancers. In additional, the increase in SBF2-AS1 expression was also correlated with tumor size ((larger vs. smaller) OR = 2.34, 95% CI: 1.47-3.70, P = 0.0003), advanced TNM stage ((III/IV vs. I/II) OR = 2.78, 95% CI: 1.75-4.41, P < 0.0001), lymph node metastasis ((Positive vs. Negative) OR = 3.06, 95% CI: 1.93-4.86, P < 0.00001), and histological grade ((poorly vs. well/moderately) OR = 2.58, 95% CI: 1.47-4.52, P = 0.001) in patients with cancer. Furthermore, The Cancer Genome Atlas (TCGA) dataset valuated that SBF2-AS1 was upregulated in a variety of tumors, and predicted the worse prognosis.Conclusions:Our results of this meta-analysis demonstrate that high SBF2-AS1 expression may become a potential target for predicting the prognosis of human cancers.

Downregulation of SBF2-AS1 functions as a tumor suppressor in clear cell renal cell carcinoma by inhibiting miR-338-3p-targeted ETS1.

Clear cell renal cell carcinoma (ccRCC) is the most prevalent type of kidney cancer in adults, accompanied by an increasing incidence rate worldwide. We found that SBF2-AS1 was a differentially expressed long-noncoding RNA (lncRNA) in ccRCC through the microarray-based expression analyses. The aim of the present study was to explore the role of SBF2-AS1 in ccRCC development by assessing its effects on cellular processes and further investigate the underlying mechanism. SBF2-AS1 was found to be highly expressed in ccRCC tissues and cells. Ectopic expression and knockdown of SBF2-AS1 and miR-338-3p were performed in ccRCC 768-O cells to explore their effects on cell proliferation, migration, invasion, apoptosis and autophagy by EdU assay, scratch test, Transwell assay, calcein-AM/PI, and GFP-LC3 immunofluorescence assays, respectively. The interactions among SBF2-AS1, miR-338-3p and ETS1 were analyzed using dual-luciferase reporter, RIP and RNA pull-down assays. SBF2-AS1 specifically bound to miR-338-3p and inhibited its expression. Moreover, ETS1 was targeted by miR-338-3p. The knockdown of SBF2-AS1 or ETS1 or overexpression of miR-338-3p resulted in reduced cell proliferation, migration and invasion but elevated cell apoptosis and autophagy. In vivo experiments verified the tumor-suppressive role of silencing SBF2-AS1 in tumor growth of nude mice xenografted with ccRCC cells. Thus, silencing SBF2-AS1 exerted suppressive effects on ccRCC by elevating miR-338-3p and suppressing ETS1.

Long Noncoding RNASBF2-AS1 Promotes Gastric Cancer Progression via Regulating miR-545/EMS1 Axis.

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.

Down-regulated lncRNA SBF2-AS1 in M2 macrophage-derived exosomes elevates miR-122-5p to restrict XIAP, thereby limiting pancreatic cancer development.

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‐γ 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.

LncRNA SBF2-AS1 affects the radiosensitivity of non-small cell lung cancer via modulating microRNA-302a/MBNL3 axis

ABSTRACT Background: Long non-coding RNAs (lncRNAs) have been reported to participate in many diseases including non-small cell lung cancer (NSCLC), thus our objective was to investigate the impact of lncRNA SBF2-AS1 modulating microRNA-302a (miR-302a) expression on radiosensitivity of NSCLC. Methods: The expression of SBF2-AS1, miR-302a and muscleblind-like 3 (MBNL3) in NSCLC tissues of the radiotherapy-sensitive and radiotherapy-resistant groups was tested. The radiosensitivity of parent and resistant strains (NCI-H1299 and NCI-H1299R cells) was detected. Further, cells were treated with si-SBF2-AS1 and miR-302a mimics to determine their roles in proliferation and apoptosis of parent strain and resistant strain cells as well as transfected cells. The in-vivo growth capacity of the cells and the effect of radiotherapy on tumor size of NSCLC were detected. Results: Up-regulated SBF2-AS1 and MBNL3 and down-regulated miR-302a in NSCLC tissues of the radiotherapy resistant group. Overexpression of SBF2-AS1 and MBNL3 and low expression of miR-302a were witnessed in NCI-H1299R cells. Down-regulated SBF2-AS1 or up-regulated miR-302a suppressed the proliferation while boosted the apoptosis of NCI-H1299 cells and decreased the radioresistance of the NCI-H1299R cells. Silencing SBF2-AS1 or up-regulating miR-302a restrained tumor growth in vivo. Conclusion: Our study presents that high expression of miR-302a or inhibition of SBF2-AS1 can enhance the radiosensitivity and apoptosis of NSCLC cells through downregulation of MBNL3, which is a therapeutic target for NSCLC.

Long non-coding SBF2-AS1 acting as a competing endogenous RNA to sponge microRNA-142-3p to participate in gemcitabine resistance in pancreatic cancer via upregulating TWF1.

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.

Silencing of long noncoding RNA SBF2-AS1 inhibits proliferation, migration and invasion and contributes to apoptosis in osteosarcoma cells by upregulating microRNA-30a to suppress FOXA1 expression

ABSTRACTObjectives: Long noncoding RNA (lncRNA) SBF2-AS1 was found to be related to some tumors. Nevertheless, the role of SBF2-AS1 in osteosarcoma (OS) is still needed to be elaborated. This study is conducted to examine the expression of lncRNA SBF2-AS1 in OS with the involvement of microRNA-30a (miR-30a) and FOXA1.Methods: OS tissues and its corresponding adjacent normal tissues were obtained for the detection of SBF2-AS1 expression and its relations with clinical phenotypes. OS cells with most significant expression of SBF2-AS1 were selected for subsequent experiments. Moreover, a series of experiments were performed to detect proliferation, invasion, migration, colony formation, cell cycle distribution and apoptosis of OS cells. Furthermore, the binding site between SBF2-AS1 and miR-30a as well as between miR-30a and FOXA1 was verified.Results: SBF2-AS1 was overexpressed in tissues and cells of OS. Additionally, silencing of SBF2-AS1 and miR-30a overexpression inhibited the proliferation, migration and invasion of OS cells and promoted their apoptosis. Moreover, lncRNA SBF2-AS1 regulated miR-30a by serving as a ceRNA, thus promoting FOXA1 expression. Furthermore, interfered SBF2-AS1 or upregulated miR-30a restrained the growth of OS.Conclusion: Our study confirms that silencing of SBF2-AS1 represses proliferation, migration and invasion of OS cells and promotes their apoptosis by binding to miR-30a and inhibiting FOXA1 expression.

Long noncoding RNA SBF2-AS1 act as a ceRNA to modulate cell proliferation via binding with miR-188-5p in acute myeloid leukemia

LncRNA SBF2-AS1 has been reported to be implicated in the deterioration of multiple human cancers. However, the roles and underlying mechanisms of SBF2-AS1 in acute myeloid leukemia (AML) are still unclear. In the present study, the online GEPIA database showed that SBF2-AS1 expression was significantly increased in AML samples. QRT-PCR results showed that SBF2-AS1 expression was upregulated in AML cells. CCK-8 assay revealed that SBF2-AS1 inhibition decreased AML cells proliferation ability in vitro. Flow cytometry assays showed that SBF2-AS1 inhibition induced AML cells apoptosis and arrested AML cells in G0/G1 phase. Mechanistically, miR-188-5p was identified as a direct target of SBF2-AS1. SBF2-AS1 upregulated the expression level of ZFP91 by sponging miR-188-5p. And the effects of SBF2-AS1 suppression on AML cells progression could be abolished by miR-188-5p inhibitors. Moreover, we found that SBF2-AS1 inhibition reduced tumor growth in vivo. Taken together, our findings elucidated that SBF2-AS1 could act as a miRNA sponge in AML progression, and provided a potential therapeutic strategy for AML treatment.

Long Noncoding RNA SBF2-AS1 Is Critical for Tumorigenesis of Early-Stage Lung Adenocarcinoma

Emerging evidence demonstrates that long non-coding RNAs (lncRNAs) are deeply involved in the development of various cancers. This study identified that SBF2-AS1, an early-stage-specific lncRNA, is critical for the tumorigenesis of lung adenocarcinoma (LUAD). We first analyzed LUAD transcriptome data from The Cancer Genome Atlas and the GEO database by weighted gene co-expression network analysis (WGCNA). Five early LUAD-specific lncRNAs were filtered out, and only SBF2-AS1 was upregulated in LUAD. High expression of SBF2-AS1 indicates poor survival of LUAD, especially the early-stage LUAD, but not lung squamous cell carcinoma. SBF2-AS1 promotes LUAD cells proliferation in vitro, and RNA-sequencing data shows that many cell-cycle-related genes were downregulated after SBF2-AS1 knockdown. Mechanically, SBF2-AS1 could competitively bind with miR-338-3p and miR-362-3p to increase E2F1 expression. Finally, we show that the SBF2-AS1-miR-338-3p/362-3p-E2F1 axis could promote LUAD tumorigenesis in vitro and in vivo. Our study demonstrates that SBF2-AS1, an early-stage-specific lncRNA, promotes LUAD tumorigenesis by sponging miR-338-3p and miR-362-3p and increasing E2F1 expression. The SBF2-AS1-miR-338-3p/362-3p-E2F1 regulatory axis may serve as a prognostic marker and potential therapeutic target for LUAD.

Long noncoding RNA SBF2-AS1 promotes colorectal cancer proliferation and invasion by inhibiting miR-619-5p activity and facilitating HDAC3 expression.

Evidence, demonstrating long noncoding RNAs (lncRNAs) as critical players in cancer, remains to increase. lncRNA SBF2-AS1 was reported to be involved in several cancers, such as hepatocellular carcinoma. However, the role of SBF2-AS1 in colorectal cancer (CRC) is unknown. We showed lncRNA SBF2-AS1 expression was growing in CRC samples, especially in advanced cases. Accordingly, SBF2-AS1 possesses higher expression in CRC cell lines than in normal cell line. Moreover, SBF2-AS1 high expression indicated a low survival rate. Functionally, SBF2-AS1 knockdown suppressed the proliferation, migration, and invasion of CRC cells. In terms of mechanism, SBF2-AS1 upregulation restrained the activity of miR-619-5p and led to overexpression of HDAC3. Importantly, downregulation of miR-619-5p or HDAC3 overexpression reversed SBF2-AS1-silencing-caused suppression on proliferation and metastasis. Summarily, our findings elucidated a crucial role of SBF2-AS1 as a miR-619-5p sponge, shedding novel light on lncRNA-related prognostics.

LncRNA SBF2-AS1 promotes the progression of cervical cancer by regulating miR-361-5p/FOXM1 axis

Long non-coding RNAs (lncRNAs) have been identified as critical players in tumorigenesis. Previous studies revealed that lncRNA SBF2-AS1 was involved in tumor progression. However, the role and underlying mechanism of SBF2-AS1 in cervical cancer (CC) remain unknown. In the present study, our data showed that SBF2-AS1 expression was significantly increased in CC. High SBF2-AS1 expression was associated with advanced FIGO stage and lymph node metastasis of CC patients. Function assays showed that SBF2-AS1 inhibition significantly reduced CC cells proliferation both in vitro and in vivo. Mechanistically, we showed that SBF2-AS1 upregulation restrained the activity of miR-361-5p and led to overexpression of FOXM1 in CC cells. Furthermore, we found that miR-361-5p inhibitors could rescue the effects of SBF2-AS1 inhibition on CC cells proliferation. Taken together, we demonstrated that the SBF2-AS1/miR-361-5p/FOXM1 axis might play an important role in CC progression. SBF2-AS1 might serve as a potential therapeutic target for CC treatment.

Comment on: LncRNA SBF2-AS1 promotes hepatocellular carcinoma metastasis by regulating EMT and predicts unfavorable prognosis.

Objective Recent studies have furthered our understanding of the function of long noncoding RNAs (lncRNAs) in numerous biological processes, including cancer. The present study aimed to investigate the expression of lncRNA SBF2-AS1 (SBF2-AS1) in patients with hepatocellular carcinoma (HCC) and to investigate its effect on HCC cells. Patients and methods Using quantitative reverse transcription-polymerase chain reaction, we detected SBF2-AS1 expression in HCC cell lines and primary tumor tissues. The associations between SBF2-AS1 expression and the clinicopathological factors and outcome of HCC patients were statistically analyzed. MTT assay and transwell assay were performed to determine the proliferation, migration and invasion, respectively. In addition, we evaluated the activation of Mesenchymal-epithelial transition (EMT) pathway by Western blot. Results We found that SBF2-AS1 expression levels were significantly up-regulated in HCC tissues and cell lines compared with the corresponding noncancerous liver tissues and normal hepatic cell line. In addition, high SBF2-AS1 expression levels were correlated with vein invasion (p = 0.008) and TNM stage (p = 0.013). Furthermore, Kaplan-Meier survival analysis indicated that high expressions of SBF2-AS1 were correlated with shorter overall survival of HCC patients. Univariate and multivariate analysis identified high SBF2-AS1 expression as an unfavorable prognostic factor for overall survival. Further functional analysis demonstrated that knockdown of SBF2-AS1 significantly inhibited HCC cells proliferation, migration and invasion. Mechanistically, we found that SBF2-AS1 could promote the activation of EMT pathway, which was demonstrated by measuring the expression levels of EMT-related markers. Conclusions SBF2-AS1 might be considered as a novel molecule involved in HCC development, which provides a potential therapeutic target for HCC.

LncRNA SBF2-AS1 promotes hepatocellular carcinoma metastasis by regulating EMT and predicts unfavorable prognosis.

Recent studies have furthered our understanding of the function of long noncoding RNAs (lncRNAs) in numerous biological processes, including cancer. The present study aimed to investigate the expression of lncRNA SBF2-AS1 (SBF2-AS1) in patients with hepatocellular carcinoma (HCC) and to investigate its effect on HCC cells. Using quantitative reverse transcription-polymerase chain reaction, we detected SBF2-AS1 expression in HCC cell lines and primary tumor tissues. The associations between SBF2-AS1 expression and the clinicopathological factors and outcome of HCC patients were statistically analyzed. MTT assay and transwell assay were performed to determine the proliferation, migration and invasion, respectively. In addition, we evaluated the activation of Mesenchymal-epithelial transition (EMT) pathway by Western blot. We found that SBF2-AS1 expression levels were significantly up-regulated in HCC tissues and cell lines compared with the corresponding noncancerous liver tissues and normal hepatic cell line. In addition, high SBF2-AS1 expression levels were correlated with vein invasion (p = 0.008) and TNM stage (p = 0.013). Furthermore, Kaplan-Meier survival analysis indicated that high expressions of SBF2-AS1 were correlated with shorter overall survival of HCC patients. Univariate and multivariate analysis identified high SBF2-AS1 expression as an unfavorable prognostic factor for overall survival. Further functional analysis demonstrated that knockdown of SBF2-AS1 significantly inhibited HCC cells proliferation, migration and invasion. Mechanistically, we found that SBF2-AS1 could promote the activation of EMT pathway, which was demonstrated by measuring the expression levels of EMT-related markers. SBF2-AS1 might be considered as a novel molecule involved in HCC development, which provides a potential therapeutic target for HCC.