Silencing of long noncoding RNA LEF1-AS1 prevents the progression of hepatocellular carcinoma via the crosstalk with microRNA-136-5p/WNK1

Long noncoding RNAs (lncRNAs) have been recognized as cancer-associated biological molecules, favoring hepatocellular carcinoma (HCC) progression. This study was conducted to elucidate the effects lncRNA lymphoid enhancer-binding Factor 1 antisense RNA (LEF1-AS1) on the pathological development of HCC, along with the crosstalk involving microRNA-136-5p (miR-136-5p) and with-no-K (lysine) kinase 1 (WNK1). The study recruited primary HCC tissues and their corresponding nonneoplastic liver tissues. The gain- and loss-of-function studies were performed in HCC cells HuH-7 and tumor xenografts in nude mice. The dual luciferase reporter gene assay system, RNA pull-down, and radioimmunoprecipitation assays were applied to detect their interactions among lncRNA LEF1-AS1, miR-136-5p, and WNK1. 5-Ethynyl-2′-deoxyuridine staining, scratch test, Transwell assays, and in vitro tube formation assays were conducted to examine HCC cell proliferation, migration, and invasion and HUVEC angiogenesis. HCC tissues and cells contained high lncRNA LEF1-AS1 expression. LncRNA LEF1-AS1 upregulation triggered markedly increased HCC cell proliferation, migration, and invasion and human umbilical vein endothelial cell angiogenesis. In vivo silencing lncRNA LEF1-AS1 resulted in reduced tumor cell vitality and matrix metalloproteinase-9 and the vascular endothelial growth factor expression. Additionally, the role of lncRNA LEF1-AS1 was found to be largely dependent on WNK1. Association of lncRNA LEF1-AS1 with WNK1 blocked the inhibitory effect of miR-136-5p on WNK1, which was confirmed by in vivo experiments. Altogether, our results revealed an important role of lncRNA LEF1-AS1 in regulating the HCC progression by regulating WNK1, providing a potential biomarker for the therapeutic modalities regarding HCC.     

Long noncoding RNA LEF1-AS1 silencing suppresses the initiation and development of prostate cancer by acting as a molecular sponge of miR-330-5p via LEF1 repression

Prostate cancer (PCa) is one of the major cancers affecting males with high mortality around the world. Recent studies have found that some long noncoding RNAs play a critical part in the cellular processes of PCa. In our study, aberrant expressed lymphoid enhancer-binding factor-1 antisense RNA 1 (LEF1-AS1), microRNA-330-5p (miR-330-5p), and lymphoid enhancer-binding factor-1 (LEF1) were screened out from a microarray database, the role of the novel noncoding RNA regulatory circuitry in the initiation and development of PCa was investigated. LEF1-AS1 and LEF1 were highly expressed while miR-330-5p was poorly expressed in PCa. Following that, the PCa PC-3 cell line was adopted for subsequently experiments, in which the expression of LEF1-AS1 and miR-330-5p was subsequently altered by means of exogenous transfection. After that, the effects of up- or downregulation of LEF1-AS1 and miR-330-5p on epithelial–mesenchymal transition (EMT) and the cell ability for proliferation, invasion, migration in vitro, and tumorigenesis and lymph node metastasis (LNM) in vivo were evaluated. RNA crosstalk revealed that LEF1-AS1 bound to miR-330-5p and LEF1 was the target gene of miR-330-5p. Silenced LEF1-AS1 or elevated miR-330-5p exhibited inhibited EMT processes, reduced ability of proliferation, invasion and migration, coupling with decreased tumorigenesis and LNM in nude mice. The key findings of this study collectively propose downregulation of LEF1-AS1 competing with miR-330-5p to inhibit EMT, invasion and migration of PCa by LEF1 repression.     

Long noncoding RNA LEF1-AS1 binds with HNRNPL to boost the proliferation,migration, and invasion in osteosarcoma by enhancing the mRNA stability of LEF1

Osteosarcoma (OS) is the most frequent type of cancer that starts in the bones, with a rather high tendency to metastasize to other bones at the early stages. Although many types of research have demonstrated that long noncoding RNAs commonly take part in the development of various cancers, the modulating mechanism of LEF1-AS1 in OS was unknown yet. In this study, our results disclosed that LEF1-AS1, as well as LEF1, had higher expression levels in OS cells than that in normal bone cells. LEF1-AS1 knockdown dramatically inhibited the proliferation, migration, as well as invasion in OS, which proved that LEF1-AS1 contributed to the growth of OS. Furthermore, HNRNPL knockdown suppressed the expression of LEF1. LEF1-AS1 was confirmed to sponge HNRNPL and HNRNPL could bind with LEF1. Both LEF1-AS1 and HNRNPL could enhance the stability of LEF1 mRNA. LEF1-AS1 acted as a promoter in stimulating the Wnt signaling pathway in OS. In rescue experiments, overexpression of LEF1 partially offset the inhibition LEF1-AS1 knockdown brought in the proliferation, migration as well as invasion of OS cells. Collectively, this study had investigated that LEF1-AS1 bound with HNRNPL to promote OS cell proliferation, migration as well as invasion by enhancing the messenger RNA stability of LEF1.     

Long noncoding RNA DLX6-AS1 promotes liver cancer by increasing the expression of WEE1 via targeting miR-424-5p

Long noncoding RNAs (lncRNAs) played an important role in tumorigenesis and development of hepatocellular carcinoma (HCC). In this study, we first demonstrated that lncRNA DLX6 antisense RNA 1 (DLX6-AS1) was upregulated in cancer tissues and cells lines compared with normal adjacent and cell line. Knock-down DLX6-AS1 by transfection with small interfering RNA (siRNA) suppressed cell proliferation, migration, and invasion of HCC cells. Cell cycle analysis showed that cells transfected with siRNA were arrested in G0/G1 phase. Then, we performed dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay to show that DLX6-AS1 could bind with miR-424-5p. And cotransfection inhibitor of miR-424-5p with siRNA of DLX6-AS1 could abolish the inhibitory effect of siRNA of DLX6-AS1 on cell proliferation, migration, and invasion. Moreover, we further demonstrated that the oncogene WEE1 G2 checkpoint kinase (WEE1) was the target of miR-424-5p and expression levels of WEE1 were positive correlation with that of DLX6-AS1. Taken together, these results suggested that upregulated DLX6-AS1 promoted cell proliferation, migration, and invasion of HCC through increasing expression of WEE1 via targeting miR-424-5p.     

MiR-526b targets lncRNA SLC16A1-AS1 to suppress cell proliferation in triple-negative breast cancer

The present study investigated the potential interaction between miR-526b and lncRNA SLC16A1-AS1 in triple-negative breast cancer (TNBC). Expression of miR-526b and SLC16A1-AS1 in TNBC tumor tissues and paired nontumor tissues from 60 TNBC patients was detected by real-time polymerase chain reaction (RT-qPCR). The interaction between miR-526b and SLC16A1-AS1 was evaluated with overexpression experiments, followed by RT-qPCR. The proliferation and migration of cells were detected with cell counting kit-8 assay and Transwell assay, respectively. Apoptosis of cells was assessed by cell apoptosis assay. The expression of apoptosis-related proteins was quantified by Western blot analysis. MiR-526b was predicted to bind with SLC16A1-AS1. Overexpression of miR-526b in TNBC cells decreased the expression levels of SLC16A1-AS1, while overexpression of SLC16A1-AS1 did not affect the expression of miR-526b. In TNBC tissues, miR-526b was downregulated in TNBC tissues, while SLC16A1-AS1 was upregulated in TNBC tissues compared to that in nontumor tissues. The expression of SLC16A1-AS1 and miR-526b were inversely correlated. In vitro experiments showed that overexpression of SLC16A1-AS1 promoted cell proliferation and invasion but suppressed cell apoptosis. MiR-526b played an opposite role and suppressed the function of SLC16A1-AS1. MiR-526b is downregulated in TNBC and it targets SLC16A1-AS1 to regulate proliferation, apoptosis, and invasion of TNBC cells.     

Long noncoding RNA SOX21-AS1 promotes cervical cancer progression by competitively sponging miR-7/VDAC1

Growing evidence has shown that long noncoding RNAs (lncRNAs) play crucial roles in cervical cancer. Dy000sregulation of lncRNA SOX21 antisense RNA 1 (SOX21-AS1) has been reported in several tumors. However, its expression pattern and potential biological function in cervical cancer (CC) have not been investigated. In this study, we first reported that SOX21-AS1 expression was significantly upregulated in both CC tissues and cell lines. High expression of SOX21-AS1 was found to be significantly correlated with Federation of Gynecology and Obstetrics (FIGO) stage, lymph node metastasis and depth of cervical invasion. Further clinical assay confirmed that high SOX21-AS1 expression was associated with shorter overall survival and could be used as a potential prognostic biomarker for CC patients. Functional investigation showed that knockdown of SOX21-AS1 suppressed CC cells proliferation, migration, and invasion, as well as epithelial to mesenchymal transition progress. Furthermore, our data showed that microRNA-7 (miR-7) interacted with SOX21-AS1 by directly targeting the miRNA-binding site in the SOX21-AS1 sequence, and quantitative real-time polymerase chain reaction results showed overexpression of SOX21-AS1 decreased the levels of miR-7 in CC cells. Moreover, we confirmed that miR-7 directly targeted the 3′-untranslated region of voltage dependent anion channel 1 (VDAC1). Final in vitro assay suggested that in CC cells with SOX21-AS1, VDAC1 overexpression resulted in an increase of cell proliferation, migration, and invasion. Overall, our findings illuminate how SOX21-AS1 formed a regulatory network to confer an oncogenic function in CC and SOX21-AS1 could be regarded as an efficient therapeutic target and potential biomarker for CC patients.     

E2F1-mediated MNX1-AS1-miR-218-5p-SEC61A1 feedback loop contributes to the progression of colon adenocarcinoma

The long noncoding RNA MNX1-AS1 has been reported to facilitate the progression of glioblastoma and ovarian cancer. Nevertheless, the biological roles and underlying mechanisms of MNX1-AS1 in colon adenocarcinoma have not been studied until now. In the current study, MNX1-AS1 was upregulated in colon adenocarcinoma. JASPAR prediction tool showed that E2F1 could bind to the promoter region of MNX1-AS1. The chromatin immunoprecipitation assay and luciferase reporter assay were used to verify the interactions between MNX1-AS1 and E2F1. Then functional assays revealed that downregulation of MNX1-AS1 decreased cell proliferation, migration, and invasion in colon adenocarcinoma, but upregulation of E2F1 reversed the effects. Moreover, subcellular fractionation assay manifested that MNX1-AS1 was enriched in the cytoplasm of colon adenocarcinoma cells, thus we speculated whether MNX1-AS1 could function as a competing endogenous RNA (ceRNA) to play roles in colon adenocarcinoma. Bioinformatics analysis and luciferase reporter assay indicated that MNX1-AS1 could sponge microRNA-218-5p (miR-218-5p). Furthermore, we discovered that SEC61A1 was downstream target of miR-218-5p, and MNX1-AS1 acted as a ceRNA to upregulate the expression of SEC61A1 through sponging miR-218-5p. Finally, rescue assays confirmed that MNX1-AS1 facilitated the progression of colon adenocarcinoma through regulating miR-218-5p/SEC61A1 axis. Taken together, we concluded that E2F1-mediated MNX1-AS1-miR-218-5p-SEC61A1 feedback loop contributed to the progression of colon adenocarcinoma.     

LncRNA HAND2-AS1 inhibits 5-fluorouracil resistance by modulating miR-20a/PDCD4 axis in colorectal cancer

BackgroundChemoresistance is one of the main obstacles in the therapy of human cancers, including colorectal cancer (CRC). Long non-coding RNA heart and neural crest derivatives expressed 2-antisense RNA 1 (lncRNA HAND2-AS1) has been demonstrated to be associated with CRC. However, the function of HAND2-AS1 in 5-Fluorouracil (5-FU) resistance of CRC remains unclear.MethodsQuantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expression of HAND2-AS1, miR-20a and programmed cell death factor 4 (PDCD4) mRNA. 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay was conducted to evaluate IC50 of 5-FU and cell proliferation. Flow cytometry analysis was used to determine cell apoptosis. Transwell assay was carried out to measure cell migration and invasion. Western blot assay was conducted to examine the protein levels of B-cell lymphoma-2 (Bcl-2), BCL2-Associated X (Bax), matrix metalloprotein 2 (MMP2), MMP9 and PDCD4. Dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull down assay were utilized to verify the combination between miR-20a and HAND2-AS1. Dual-luciferase reporter assay was used to analyze the association between miR-20a and PDCD4. Murine xenograft assay was used to confirm the function of HAND2-AS1 in vivo.ResultsHAND2-AS1 and PDCD4 were downregulated and miR-20a was upregulated in 5-FU-resistant CRC tissues and cells. HAND2-AS1 suppressed 5-FU resistance, cell proliferation, migration and invasion and promoted cell apoptosis in 5-FU-resistant CRC cells. HAND2-AS1 acted as a sponge of miR-20a to regulate PDCD4 expression. Moreover, HAND2-AS1 suppressed cell progression and 5-FU resistance by upregulating PDCD4 via sponging miR-20a in 5-FU-resistant CRC cells. Besides, HAND2-AS1 inhibited tumor growth in vivo.ConclusionHAND2-AS1/miR-20a/PDCD4 axis inhibited cell progression and 5-FU resistance in 5-FU-resistant CRC cells.     

HOXC13-AS promotes breast cancer cell growth through regulating miR-497-5p/PTEN axis

Dysregulated long noncoding RNAs (lncRNAs) remains to be explored in tumorigenesis. LncRNA HOXC13 antisense RNA (HOXC13-AS) has been found as an oncogene in many cancers; however, the role of HOXC13-AS in breast cancer still elusive. In this study, the HOXC13-AS levels and its role in cell proliferation was first measured by real-time quantitative polymerase chain reaction, Cell Counting Kit-8 assay, and colony formation assay. It showed that HOXC13-AS was increased in breast cancer tissues compared with the adjacent normal tissues and upregulated HOXC13-AS promoted the growth of breast cancer cells. Then, we found that the miR-497-5p levels were downregulated in cancer tissues compared with the adjacent tissues and miR-497-5p suppressed breast cancer cell proliferation. Further study showed that HOXC13-AS could function as a “sponge” for miR-497-5p then suppress miR-497-5p expression. Moreover, we next identified that Phosphatase and Tensin homolog (PTEN) is the target of miR-497-5p. Overexpression of miR-497-5p by chemical mimics decreased the expression of PTEN, while downregulation of miR-497-5p by HOXC13-AS rescued the expression of PTEN. Finally, we showed that HOXC13-AS promoted the proliferation of breast cancer cells and tumor growth through miR-497-5p/PTEN axis in vitro and in vivo. Hence, we conclude that HOXC13-AS, which is significantly upregulated in breast cancers, promoted cell proliferation through the suppressed miR-497-5p and further upregulated PTEN.     

LncRNA DLX6-AS1 promotes tumor proliferation and metastasis in osteosarcoma through modulating miR-641/HOXA9 signaling pathway

Osteosarcoma (OS) is the most common primary malignant bone tumor. Recently, increasing evidence has shown that the long noncoding RNA (lncRNA) DLX6-AS1 (distal-less homeobox 6 antisense 1) plays significant roles in various types of cancers. However, the functions and underlying mechanisms of DLX6-AS1 have not been explored in OS yet. In this study, we assessed the expression of DLX6-AS1 in OS tissues and cell lines and explored the underlying molecular mechanisms. DLX6-AS1 was found to be significantly upregulated in OS tissues and OS cell lines. High expression of DLX6-AS1 was significantly correlated with advanced TNM stage, high tumor grade, and distant metastasis of patients with OS. Knockdown of DLX6-AS1 suppressed OS cell proliferation, invasion, and migration, and induced cell apoptosis. Knockdown of DLX6-AS1 also suppressed in vivo tumor growth. Bioinformatics and luciferase assay analysis showed that DLX6-AS1 functioned as a competing endogenous RNA (ceRNA) to negatively regulate miR-641 expression. Furthermore, miR-641 was found to target the 3′ untranslated region of homeobox protein Hox-A9 (HOXA9) and suppressed the expression of HOXA9. Mechanistic studies showed that DLX6-AS1 regulated OS cell proliferation, invasion, and migration via regulating HOXA9 by acting as a ceRNA for miR-641. Our results suggested that DLX6-AS1 functions as a ceRNA by targeting miR-641/HOXA9 signal pathway to suppress OS cell proliferation and metastasis. Our study may provide novel insights into understanding pathogenesis and development of OS.     

长非编码RNA ILF3-AS1通过调控miR-130a-3p/PTEN轴抑制宫颈癌细胞的增殖

ILF3反义RNA 1（ILF3 antisense RNA 1,ILF3-AS1）是一条定位于染色体19p13.2的lncRNA,它是白介素增强子结合因子3 (interleukin enhancer binding factor 3,ILF3)的反义RNA。ILF3-AS1在多种肿瘤发生发展中发挥关键作用,但其在宫颈癌中的作用尚无研究探讨。本文利用TCGA及GTEx数据库进行生物信息学分析提示,ILF3-AS1在宫颈癌组织中低表达（P<0.001）并与良好预后相关（P=0.045）。qRT-PCR结果显示,ILF3-AS1在宫颈癌组织及SiHa、HeLa、CaSki宫颈癌细胞系中表达较对照组均呈下降趋势。过表达ILF3-AS1可明显抑制宫颈癌细胞增殖活力及促进宫颈癌细胞凋亡。Star Base v3.0数据库分析提示,ILF3-AS1可靶向吸附miR-130a-3p;而miR-130a-3p可靶向结合PTEN。qRT-PCR检测显示,miR-130a-3p在宫颈癌中的表达量明显高于正常宫颈组织（P<0.01）。荧光素酶报告基因结果显示,ILF3-AS1可以与miR-130a-3p 特异性结合（P<0.01）。HeLa细胞过表达ILF3-AS1后,miR-130a-3p表达量明显下调（P<0.01）;在过表达ILF3-AS1细胞中,同时转染miR-130a-3p mimics,能部分逆转LF3-AS1对于细胞增殖的抑制作用（P<0.001）。HeLa细胞在过表达ILF3-AS1后,磷酸酶及张力蛋白同源物基因(phosphatase and tensin homolog deleted on chromosome ten,PTEN) mRNA（P<0.001）及蛋白质（P<0.001）表达量显著升高;当同时转染miR-130a-3p mimics,PTEN的 mRNA（P<0.001)及蛋白质（P<0.001）的表达升高被明显抑制。综上,ILF3-AS1可以作为miR-130a-3p的吸附海绵靶向调控PTEN表达,从而抑制宫颈癌细胞的增殖。     

Long noncoding RNA FOXD2-AS1 promotes glioma malignancy and tumorigenesis via targeting miR-185-5p/CCND2 axis

Glioma is the most aggressive malignant tumor in the adult central nervous system. Abnormal long noncoding RNA (lncRNA) FOXD2-AS1 expression was associated with tumor development. However, the possible role of FOXD2-AS1 in the progression of glioma is not known. In the present study, we used in vitro and in vivo assays to investigate the effect of abnormal expression of FOXD2-AS1 on glioma progression and to explore the mechanisms. FOXD2-AS1 was upregulated in glioma tissue, cells, and sphere subpopulation. Upregulation of FOXD2-AS1 was correlated with poor prognosis of glioma. Downregulation of FOXD2-AS1 decreased cell proliferation, migration, invasion, stemness, and epithelial-mesenchymal transition (EMT) in glioma cells and inhibited tumor growth in transplanted tumor. We also revealed that FOXD2-AS1 was mainly located in cytoplasm and microRNA (miR)-185-5p both targeted FOXD2-AS1 and CCND2 messenger RNA (mRNA) 3′-untranslated region (3′-UTR). miR-185-5p was downregulated in glioma tissue, cells, and sphere subpopulation. Downregulation of miR-185-5p was closely correlated with poor prognosis of glioma patients. In addition, miR-185-5p mimics decreased cell proliferation, migration, invasion, stemness, and EMT in glioma cells. CCND2 was upregulated in glioma tissue, cells, and sphere subpopulation. Upregulation of CCND2 was closely correlated with poor prognosis of glioma patients. CCND2 knockdown decreased cell proliferation, migration, invasion, and EMT in glioma cells. In glioma tissues, CCND2 expression was negatively associated with miR-185-5p, but positively correlated with FOXD2-AS1. FOXD2-AS1 knockdown and miR-185-5p mimics decreased CCND2 expression. Inhibition of miR-185-5p suppressed FOXD2-AS1 knockdown-induced decrease of CCND2 expression. Overexpression of CCND2 suppressed FOXD2-AS1 knockdown-induced inhibition of glioma malignancy. Taken together, our findings highlight the FOXD2-AS1/miR-185-5p/CCND2 axis in the glioma development.     

Long non-coding RNA FEZF1-AS1 induced progression of ovarian cancer via regulating miR-130a-5p/SOX4 axis

Emerging studies have revealed the critical role of long non-coding RNAs (lncRNAs) in epithelial ovarian cancer (EOC) development and progression. Till now, the roles and potential mechanisms regarding FEZF1 antisense RNA 1 (FEZF1-AS1) within ovarian cancer (OC) remain unclear. The objective of this study was to uncover the biological function and the underlying mechanism of LncRNA FEZF1-AS1 in OC progression. FEZF1-AS1 expression levels were studied in cell lines and tissues of human ovarian cancer. In vitro studies were performed to evaluate the impact of FEZF1-AS1 knock-down on the proliferation, invasion, migration and apoptosis of OC cells. Interactions of FEZF1-AS1 and its target genes were identified by luciferase reporter assays. Our data showed overexpression of FEZF1-AS1 in OC cell lines and tissues. Cell migration, proliferation, invasion, wound healing and colony formation were suppressed by silencing of FEZF1-AS1. In contrast, cell apoptosis was promoted by FEZF1-AS1 knock-down in vitro. Furthermore, online bioinformatics analysis and tools suggested that FEZF1-AS1 directly bound to miR-130a-5p and suppressed its expression. Moreover, the inhibitory effects of miR-130a-5p on the OC cell growth were reversed by FEZF1-AS1 overexpression, which was associated with the increase in SOX4 expression. In conclusion, our results revealed that FEZF1-AS1 promoted the metastasis and proliferation of OC cells by targeting miR-130a-5p and its downstream SOX4 expression.     

Long noncoding RNA MNX1-AS1 contributes to lung cancer progression through the miR-527/BRF2 pathway

Lung cancer belongs to a leading popular and malignant cancer around the world. However, the root mechanism underlying lung cancer progression remains unclear. Recently, long noncoding RNA (lncRNA) has been identified as important for tumorigenesis. LncRNA MNX1-AS1 is proven to regulate colon adenocarcinoma, cervical cancer, glioblastoma, and ovarian cancer. Whether MNX1-AS1 participates in lung cancer needs investigation. In our research, we found that MNX1-AS1 was dramatically upregulated in lung cancer. MNX1-AS1 upregulation indicated poor prognosis in lung cancer patients. Functionally, MNX1-AS1 promoted lung cancer progression through regulating proliferation, migration, and invasion. Mechanistically, MNX1-AS1 was found to locate in the cytoplasm and interact with miR-527. Through inhibiting miR-527 availability, MNX1-AS1 facilitated BRF2 expression. Restoration of BRF2 rescued defects of proliferation, migration, and invasion caused by MNX1-AS1 knockdown. Taken together, our study found a novel signaling pathway, namely MNX1-AS1/miR-527/BRF2 axis, involved in lung cancer progression.     

LncRNA HAND2-AS1 exerts anti-oncogenic effects on ovarian cancer via restoration of BCL2L11 as a sponge of microRNA-340-5p

In the early stage of ovarian cancer (OC), molecular biomarkers are critical for its diagnosis and treatment. Nevertheless, there is little research on the mechanism underlying tumorigenesis in OC. Herein, we aimed to explore whether long noncoding RNA (lncRNA) HAND2-AS1 participated in the regulation of the cell proliferation, migration, and apoptosis of OC by regulating B-cell lymphoma 2 like 11 (BCL2L11) and microRNA-340-5p (miR-340-5p). Differentially expressed lncRNAs in OC were screened by microarray-based analysis. HAND2-AS1, BCL2L11, and miR-340-5p expression was assessed in normal ovarian and OC tissues and human OC cell lines. Then, the relationships among HAND2-AS1, BCL2L11, and miR-340-5p were explored. Ectopic expression and depletion experiments were applied to analyze the effects of HAND2-AS1, miR-340-5p and BCL2L11 on migration, invasion, and proliferation of OC cells, as well as apoptosis. Lastly, the tumor xenograft in nude mice was conducted to test the tumorigenesis in vivo. In silico analysis displayed poor expression of HAND2-AS1 in OC. HAND2-AS1 specifically sponged with miR-340-5p which was found to directly target BCL2L11. Importantly, HAND2-AS1 or BCL2L11 overexpression or miR-340-5p downregulation resulted in reduction of cell invasion and migration, together with decrease of cell proliferation and increase of cell apoptosis in OC. Besides, high-expressed HAND2-AS1 inhibited the tumorigenesis in nude mice. To sum up, these data suggests HAND2-AS1 as an anti-oncogene in OC through upregulation of BCL2L11 by competitively binding to miR-340-5p, which demonstrates that there are potential diagnosis and therapy values of HAND2-AS1 in OC.     

Long noncoding RNA FEZF1-AS1 predicts poor prognosis and modulates pancreatic cancer cell proliferation and invasion through miR-142/HIF-1α and miR-133a/EGFR upon hypoxia/normoxia

Nowadays, pancreatic cancer (PC) remains the most lethal tumor, partially due to the invasive and treatment-resistant phenotype induced by the extent of hypoxic stress within the tumor tissue. According to previous studies, miR-142/HIF-1α and miR-133a/EGFR could modulate PC cell proliferation under hypoxic and normoxic conditions, respectively. In the present study, FEZF1-AS1, a recently described oncogenic long noncoding RNA, was predicted to target both miR-142 and miR-133a; thus, we hypothesized that FEZF1-AS1 might affect PC cell proliferation through these two axes under hypoxic or normoxic conditions. In PC cell lines, FEZF1-AS1 acted as an oncogene via promoting PC cell proliferation and invasion through miR-142/HIF-1α axis under hypoxic condition; however, FEZF1-AS1 failed to affect the protein levels of HIF-1α and VEGF under the normoxic condition, suggesting the existence of another signaling pathway under normoxic condition. As predicted by an online tool, FEZF1-AS1 could target miR-133a to inhibit its expression; under the normoxic condition, FEZF1-AS1 exerted its effect on PC cell lines through miR-133a/EGFR axis. Taken together, FEZF1-AS1 might be a promising target in controlling the aberrant proliferation and invasion of PC cell lines.     

LncRNA CERS6-AS1 promotes proliferation and metastasis through the upregulation of YWHAG and activation of ERK signaling in pancreatic cancer

LncRNAs play essential regulatory roles in pancreatic cancer (PC) tumorigenesis and progression. We aimed to investigate the role of lncRNA CERS6-AS1 in PC. CERS6-AS1 expression was determined in PC tissues and cell lines by PCR analysis. The roles of CERS6-AS1 on proliferation, migration, invasion, and epithelial to mesenchymal transition (EMT) were confirmed via CCK-8 assay, EDU assay, transwell assay, wound healing assay, and western blot assay. Besides, the interaction between CERS6-AS1 and their target genes was verified by luciferase report assays and RIP assays. Animal assays and clinical data analysis were performed to validate the functions in vivo. We found that lncRNA CERS6-AS1 was highly expressed in PC tissues and cells. Additionally, high expression of CERS6-AS1 was obviously associated with poor prognosis. Functional assays demonstrated that CERS6-AS1 downregulation significantly inhibited PC cell growth and migration. Moreover, CERS6-AS1 exerted as a molecular sponge for miR-217-5p (miR-217), and miR-217 was confirmed as a potential target of CERS6-AS1. Subsequently, miR-217 suppressed PC cell proliferation and metastasis by directly targeting YWHAG, which interacted with RAF1 and promoted its phosphorylation, leading to RAF1-mediated ERK signaling activation and translocation of phosphorylated ERK from the cytoplasm to the nucleus. Mechanically, CERS6-AS1 silencing significantly inhibited PC cell proliferation and metastasis via a miR-217/YWHAG/RAF1 signaling axis. CERS6-AS1 exerts as a carcinogen in PC to promote malignant features and behaves as a competitive endogenous RNA for miR-217. We identified CERS6-AS1 as a potential biomarker or therapeutic target to improve PC diagnosis and treatment outcomes.Subject terms: Oncogenes, Tumour biomarkers     

Long noncoding RNA TPT1-AS1 downregulates the microRNA-770-5p expression to inhibit glioma cell autophagy and promote proliferation through STMN1 upregulation

Through the microarray analysis, long noncoding RNA TPT1-AS1 (TPT1-AS1) was identified in the development of glioma. However, the specific effect of TPT1-AS1 on glioma autophagy in the recent years has not fully been investigated. Therefore, the purpose of our present study is to investigate the function of TPT1-AS1 on affecting autophagy of glioma cells through regulation of microRNA-770-5p (miR-770-5p)-mediated stathmin 1 (STMN1). Initially, the expression of TPT1-AS1, miR-770-5p, and STMN1 were determined in glioma cell lines, followed by the prediction and validation of their interaction. After that, the effects of TPT1-AS1, miR-770-5p, and STMN1 on the in vitro glioma cell proliferation and autophagy were assessed using EdU assay and macrophage-derived chemokine (MDC) and on the in vivo tumor development and autophagy were evaluated using a nude mouse xenograft tumor assay and immunofluorescence assay. In comparison with the normal cells, the glioma cells displayed upregulated expression of TPT1-AS1 and STMN1, but a downregulated miR-770-5p expression. miR-770-5p, which directly targeted STMN1, could be downregulated by TPT1-AS1. Subsequently, in glioma cells, TPT1-AS1 can function to competitively bind to miR-770-5p, thus regulatEing STMN1 expression. Moreover, glioma cell proliferation and autophagy could be mediated through the TPT1-AS1/miR-770-5p/STMN1 axis. From our data we conclude an inhibitory function of TPT1-AS1 in glioma cell autophagy by downregulating miR-770-5p and upregulating STMN1, which may be instrumental for the therapeutic targeting and clinical management of glioma.     

lncRNA OSER1-AS1 acts as a ceRNA to promote tumorigenesis in hepatocellular carcinoma by regulating miR-372-3p/Rab23 axis

Long non-coding RNAs (lncRNAs) are crucial regulators of tumorigenesis and progression in human cancer, including hepatocellular carcinoma (HCC). However, the role of most lncRNAs that are dysregulated in HCC remains to be elucidated. Here, we investigated the role of OSER1-AS1 in the progression of HCC. The results of database and qRT-PCR analysis demonstrated that OSER1-AS1 was highly expressed in HCC tissues and the high expression of OSER1-AS1 was closely associated with larger tumor size, advanced tumor stages, lower disease free survival and overall survival of HCC patients. OSER1-AS1 knockdown significantly inhibited the proliferation, invasion and migration of HCC cells, and induced the apoptosis. In addition, the dual luciferase reporter assay directly demonstrated that OSER1-AS1 functioned as a molecular sponge for miR-372-3p to promote Rab23 expression. Moreover, the results of immunohistochemistry and western blot analysis showed that Rab23 was highly expressed in HCC tissues, and the high expression of Rab23 was closely associated with the poor overall survival of HCC patients. Immunofluorescence assay also found the subcellular localization of Rab23 in HCC cells. Rab23 was obviously downregulated in cells that were transfected with miR-372-3p mimics. MiR-372-3p mimics significantly inhibited the proliferation and invasion of HCC cells). Rab23 restoration partially reversed miR-372-3p-induced tumor suppressive effects on HCC cells. In conclusion, we found that OSER1-AS1 acted as a ceRNA to sponge miR-372-3p, thereby positively regulating the Rab23 expression and ultimately acting as a tumor suppressor gene in HCC progression.