CircPTPRA blocks the recognition of RNA N6-methyladenosine through interacting with IGF2BP1 to suppress bladder cancer progression

Abstract Background Circular RNAs (circRNAs) have been found to have significant impacts on bladder cancer (BC) progression through various mechanisms. In this study, we aimed to identify novel circRNAs that regulate the function of IGF2BP1, a key m6A reader, and explore the regulatory mechanisms and clinical significances in BC. Methods Firstly, the clinical role of IGF2BP1 in BC was studied. Then, RNA immunoprecipitation sequencing (RIP-seq) analysis was performed to identify the circRNAs interacted with IGF2BP1 in BC cells. The overall biological roles of IGF2BP1 and the candidate circPTPRA were investigated in both BC cell lines and animal xenograft studies. Subsequently, we evaluated the regulation effects of circPTPRA on IGF2BP1 and screened out its target genes through RNA sequencing. Finally, we explored the underlying molecular mechanisms that circPTPRA might act as a blocker in recognition of m6A. Results We demonstrated that IGF2BP1 was predominantly binded with circPTPRA in the cytoplasm in BC cells. Ectopic expression of circPTPRA abolished the promotion of cell proliferation, migration and invasion of BC cells induced by IGF2BP1. Importantly, circPTPRA downregulated IGF2BP1-regulation of MYC and FSCN1 expression via interacting with IGF2BP1. Moreover, the recognition of m6A-modified RNAs mediated by IGF2BP1 was partly disturbed by circPTPRA through its interaction with KH domains of IGF2BP1. Conclusions This study identifies exonic circular circPTPRA as a new tumor suppressor that inhibits cancer progression through endogenous blocking the recognition of IGF2BP1 to m6A-modified RNAs, indicating that circPTPRA may serve as an exploitable therapeutic target for patients with BC.

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circAkap17b acts as a miR-7 family molecular sponge to regulate FSH secretion in rat pituitary cells

Journal of Molecular Endocrinology ◽

10.1530/jme-20-0036 ◽

2020 ◽

Vol 65 (4) ◽

pp. 135-148

Author(s):

Chang-Jiang Wang ◽

Fei Gao ◽

Yi-Jie Huang ◽

Dong-Xu Han ◽

Yi Zheng ◽

...

Keyword(s):

Noncoding Rna ◽

Molecular Mechanisms ◽

Target Genes ◽

Luciferase Reporter ◽

Circular Rnas ◽

Pituitary Cells ◽

Rat Pituitary ◽

Rna Immunoprecipitation ◽

Rat Pituitary Cells

The pituitary gland functions as a prominent regulator of diverse physiologic processes by secreting multiple hormones. Circular RNAs (circRNAs) are an emerging novel type of endogenous noncoding RNA that have recently been recognized as powerful regulators participating in various biological processes. However, the physiological roles and molecular mechanisms of circRNAs in pituitary remain largely unclear. Herein, we concentrated on expounding the biological function and molecular mechanism of circRNA in rat pituitary. In this study, we identified a novel circRNA in pituitary tissue, circAkap17b, which was pituitary- and stage-specific. Then, we designed circAkap17b siRNA and constructed an overexpression plasmid to evaluate the effect of loss- and gain-of-circAkap17b function on FSH secretion. Interestingly, silencing circAkakp17b significantly inhibited FSH expression and secretion, while overexpression of circAkap17b enhanced FSH expression and secretion. Furthermore, dual luciferase reporter and RNA immunoprecipitation (RIP) assays confirmed that circAkap17b could serve as miR-7 sponge to regulate target genes. Additionally, miR-7b suppressed FSH expression and secretion by directly targeting Fshb through the dual luciferase reporter and RT-qPCR analysis. Additionally, rescue experiments showed that circAkap17b could regulate FSH secretion in pituitary cells through a circAkap17b-miR-7-Fshb axis. Collectively, we demonstrated that circAkap17b could act as a molecular sponge of miR-7 to upregulate expression of the target gene Fshb and facilitate FSH secretion. These findings provide evidence for a novel regulatory role of circRNAs in pituitary.

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Mir-155 Enhances B-Cell Lymphoma Growth By Targeting TBRG1

Blood ◽

10.1182/blood.v126.23.4820.4820 ◽

2015 ◽

Vol 126 (23) ◽

pp. 4820-4820 ◽

Cited By ~ 1

Author(s):

Joost Kluiver ◽

Izabella Slezak-Prochazka ◽

Melanie Winkle ◽

Lydia Visser ◽

Arjan Diepstra ◽

...

Keyword(s):

B Cell ◽

Molecular Mechanisms ◽

Target Genes ◽

Conflicts Of Interest ◽

Cell Lymphoma ◽

Ectopic Expression ◽

B Cell Lymphoma ◽

Argonaute 2 ◽

Rna Immunoprecipitation

Abstract Several studies have indicated an important role for miR-155 in the pathogenesis of B-cell lymphoma. Highly elevated levels of miR-155 were indeed observed in most B-cell lymphomas with the exception of Burkitt lymphoma (BL). However, the molecular mechanisms that underlie the oncogenic role of miR-155 in B-cell lymphoma are not well understood. To identify the miR-155 targets relevant for B-cell lymphoma, we performed RNA immunoprecipitation of Argonaute 2 in Hodgkin lymphoma (HL) cells upon miR-155 inhibition and in BL cells upon ectopic expression of miR-155. We identified 54 miR-155-specific target genes in BL cells and confirmed miR-155 targeting of DET1, TBRG1 (NIAM1), TRIM32, HOMEZ, PSIP1 and JARID2. Five of these targets are also regulated by endogenous miR-155 in HL cells. Both overexpression of miR-155 and inhibition of expression of the miR-155 target gene TBRG1 increased proliferation of BL cells. In primary B-cell lymphoma TBRG1-positive cases have significant lower levels of miR-155 as compared to TBRG1-negative cases, suggesting that TBRG1 is also regulated by miR-155 in primary B-cell lymphoma. Thus, our data indicate that miR-155 plays an oncogenic role in B-cell lymphoma by targeting the tumor suppressor TBRG1. Disclosures No relevant conflicts of interest to declare.

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TEAD4 modulated LncRNA MNX1-AS1 contributes to gastric cancer progression partly through suppressing BTG2 and activating BCL2

Molecular Cancer ◽

10.1186/s12943-019-1104-1 ◽

2020 ◽

Vol 19 (1) ◽

Cited By ~ 12

Author(s):

You Shuai ◽

Zhonghua Ma ◽

Weitao Liu ◽

Tao Yu ◽

Changsheng Yan ◽

...

Keyword(s):

Gastric Cancer ◽

Cancer Progression ◽

Molecular Mechanisms ◽

Mechanistic Model ◽

Ectopic Expression ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Tissue Samples ◽

Reporter Assays

Abstract Background Gastric cancer (GC) is the third leading cause of cancer-related mortality globally. Long noncoding RNAs (lncRNAs) are dysregulated in obvious malignancies including GC and exploring the regulatory mechanisms underlying their expression is an attractive research area. However, these molecular mechanisms require further clarification, especially upstream mechanisms. Methods LncRNA MNX1-AS1 expression in GC tissue samples was investigated via microarray analysis and further determined in a cohort of GC tissues via quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays. Cell proliferation and flow cytometry assays were performed to confirm the roles of MNX1-AS1 in GC proliferation, cell cycle regulation, and apoptosis. The influence of MNX1-AS1 on GC cell migration and invasion was explored with Transwell assays. A xenograft tumour model was established to verify the effects of MNX1-AS1 on in vivo tumourigenesis. The TEAD4-involved upstream regulatory mechanism of MNX1-AS1 was explored through ChIP and luciferase reporter assays. The mechanistic model of MNX1-AS1 in regulating gene expression was further detected by subcellular fractionation, FISH, RIP, ChIP and luciferase reporter assays. Results It was found that MNX1-AS1 displayed obvious upregulation in GC tissue samples and cell lines, and ectopic expression of MNX1-AS1 predicted poor clinical outcomes for patients with GC. Overexpressed MNX1-AS1 expression promoted proliferation, migration and invasion of GC cells markedly, whereas decreased MNX1-AS1 expression elicited the opposite effects. Consistent with the in vitro results, MNX1-AS1 depletion effectively inhibited the growth of xenograft tumour in vivo. Mechanistically, TEAD4 directly bound the promoter region of MNX1-AS1 and stimulated the transcription of MNX1-AS1. Furthermore, MNX1-AS1 can sponge miR-6785-5p to upregulate the expression of BCL2 in GC cells. Meanwhile, MNX1-AS1 suppressed the transcription of BTG2 by recruiting polycomb repressive complex 2 to BTG2 promoter regions. Conclusions Our findings demonstrate that MNX1-AS1 may be able to serve as a prognostic indicator in GC patients and that TEAD4-activatd MNX1-AS1 can promote GC progression through EZH2/BTG2 and miR-6785-5p/BCL2 axes, implicating it as a novel and potent target for the treatment of GC.

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The role of m6A modification in the biological functions and diseases

Signal Transduction and Targeted Therapy ◽

10.1038/s41392-020-00450-x ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Xiulin Jiang ◽

Baiyang Liu ◽

Zhi Nie ◽

Lincan Duan ◽

Qiuxia Xiong ◽

...

Keyword(s):

Cancer Progression ◽

Molecular Mechanisms ◽

Target Genes ◽

Rna Modification ◽

Biological Functions ◽

Rna Methylation ◽

Downstream Target ◽

Different Types ◽

M6a Rna Methylation

AbstractN6-methyladenosine (m6A) is the most prevalent, abundant and conserved internal cotranscriptional modification in eukaryotic RNAs, especially within higher eukaryotic cells. m6A modification is modified by the m6A methyltransferases, or writers, such as METTL3/14/16, RBM15/15B, ZC3H3, VIRMA, CBLL1, WTAP, and KIAA1429, and, removed by the demethylases, or erasers, including FTO and ALKBH5. It is recognized by m6A-binding proteins YTHDF1/2/3, YTHDC1/2 IGF2BP1/2/3 and HNRNPA2B1, also known as “readers”. Recent studies have shown that m6A RNA modification plays essential role in both physiological and pathological conditions, especially in the initiation and progression of different types of human cancers. In this review, we discuss how m6A RNA methylation influences both the physiological and pathological progressions of hematopoietic, central nervous and reproductive systems. We will mainly focus on recent progress in identifying the biological functions and the underlying molecular mechanisms of m6A RNA methylation, its regulators and downstream target genes, during cancer progression in above systems. We propose that m6A RNA methylation process offer potential targets for cancer therapy in the future.

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NUSAP1 Promotes Gastric Cancer Progression Through Regulation of Yap Stability

10.21203/rs.3.rs-33883/v1 ◽

2020 ◽

Author(s):

Hui Guo ◽

Jianping Zou ◽

Ling Zhou ◽

Yan He ◽

Miao Feng ◽

...

Keyword(s):

Gastric Cancer ◽

Cancer Progression ◽

Target Genes ◽

Hippo Pathway ◽

Critical Role ◽

Xenograft Model ◽

Migration And Invasion

Abstract Background:Nucleolar and spindle associated protein (NUSAP1) is involved in tumor initiation, progression and metastasis. However, there are limited studies regarding the role of NUSAP1 in gastric cancer (GC). Methods: The expression profile and clinical significance of NUSAP1 in GC were analysed in online database using GEPIA, Oncomine and KM plotter, which was further confirmed in clinical specimens.The functional role of NUSAP1 were detected utilizing in vitro and in vivo assays. Western blotting, qRT-PCR, the cycloheximide-chase, immunofluorescence staining and Co-immunoprecipitaion (Co-IP) assays were performed to explore the possible molecular mechanism by which NUSAP1 stabilizes YAP protein. Results:In this study, we found that the expression of NUSAP1 was upregulated in GC tissues and correlates closely with progression and prognosis. Additionally, abnormal NUSAP1 expression promoted malignant behaviors of GC cells in vitro and in a xenograft model. Mechanistically, we discovered that NUSAP1 physically interacts with YAP and furthermore stabilizes YAP protein expression, which induces the transcription of Hippo pathway downstream target genes. Furthermore, the effects of NUSAP1 on GC cell growth, migration and invasion were mainly mediated by YAP. Conclusions:Our data demonstrates that the novel NUSAP1-YAP axis exerts an critical role in GC tumorigenesis and progression, and therefore could provide a novel therapeutic target for GC treatment.

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SPNS2 Downregulation Induces EMT and Promotes Colorectal Cancer Metastasis via Activating AKT Signaling Pathway

Frontiers in Oncology ◽

10.3389/fonc.2021.682773 ◽

2021 ◽

Vol 11 ◽

Author(s):

Lei Lv ◽

Qiyi Yi ◽

Ying Yan ◽

Fengmei Chao ◽

Ming Li

Keyword(s):

Colorectal Cancer ◽

Molecular Mechanisms ◽

Cancer Metastasis ◽

Epithelial Mesenchymal Transition ◽

Ectopic Expression ◽

Migration And Invasion ◽

Akt Inhibitor ◽

Colon Adenoma ◽

Mesenchymal Transition

Spinster homologue 2 (SPNS2), a transporter of S1P (sphingosine-1-phosphate), has been reported to mediate immune response, vascular development, and pathologic processes of diseases such as cancer via S1P signaling pathways. However, its biological functions and expression profile in colorectal cancer (CRC) is elusive. In this study, we disclosed that SPNS2 expression, which was regulated by copy number variation and DNA methylation of its promoter, was dramatically upregulated in colon adenoma and CRC compared to normal tissues. However, its expression was lower in CRC than in colon adenoma, and low expression of SPN2 correlated with advanced T/M/N stage and poor prognosis in CRC. Ectopic expression of SPNS2 inhibited cell proliferation, migration, epithelial–mesenchymal transition (EMT), invasion, and metastasis in CRC cell lines, while silencing SPNS2 had the opposite effects. Meanwhile, measuring the intracellular and extracellular level of S1P after overexpression of SPNS2 pinpointed a S1P-independent model of SPNS2. Mechanically, SPNS2 led to PTEN upregulation and inactivation of Akt. Moreover, AKT inhibitor (MK2206) abrogated SPNS2 knockdown-induced promoting effects on the migration and invasion, while AKT activator (SC79) reversed the repression of migration and invasion by SPNS2 overexpression in CRC cells, confirming the pivotal role of AKT for SPNS2’s function. Collectively, our study demonstrated the suppressor role of SPNS2 during CRC metastasis, providing new insights into the pathology and molecular mechanisms of CRC progression.

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Cooperation of SRPK2, Numb and p53 in the malignant biology and chemosensitivity of colorectal cancer

Bioscience Reports ◽

10.1042/bsr20191488 ◽

2020 ◽

Vol 40 (1) ◽

Author(s):

Guosen Wang ◽

Weiwei Sheng ◽

Jingtong Tang ◽

Xin Li ◽

Jianping Zhou ◽

...

Keyword(s):

Colorectal Cancer ◽

Cell Migration ◽

Cancer Progression ◽

Molecular Mechanisms ◽

Migration And Invasion ◽

Chemical Agent ◽

Cell Migration And Invasion ◽

Agent Treatment ◽

Hct116 Cells

Abstract Serine-arginine protein kinase 2 (SRPK2) is aberrantly expressed in human malignancies including colorectal cancer (CRC). However, little is known about the molecular mechanisms, and the role of SRPK2 in chemosensitivity remains unexplored in CRC. We recently showed that SRPK2 promotes pancreatic cancer progression by down-regulating Numb and p53. Therefore, we investigated the cooperation between SRPK2, Numb and p53 in the cell migration, invasion and chemosensitivity of CRC in vitro. Here, we showed that SRPK2 expression was higher in CRC tumors than in nontumor tissues. SRPK2 expression was positively associated with clinicopathological characteristics of CRC patients, including tumor differentiation, T stage, N stage and UICC stage. Additionally, SRPK2 had no association with mutant p53 (mtp53) in SW480 and SW620 cells, but negatively regulated Numb and wild-type p53 (wtp53) in response to 5-fluorouracil or cisplatin treatment in HCT116 cells. Moreover, SRPK2, Numb and p53 coimmunoprecipitated into a triple complex with or without the treatment of 5-fluorouracil in HCT116 cells, and p53 knockdown reversed the up-regulation of wtp53 induced by SRPK2 silencing with chemical agent treatment. Furthermore, overexpression of SRPK2 increased cell migration and invasion and decreased chemosensitivity to 5-fluorouracil or cisplatin in HCT116 cells. Conversely, SRPK2 silencing decreased cell migration and invasion and increased chemosensitivity to 5-fluorouracil or cisplatin, yet these effects could be reversed by p53 knockdown under chemical agent treatment. These results thus reveal a novel role of SRPK2-Numb-p53 signaling in the progression of CRC and demonstrate that SRPK2 is a potential therapeutic target for CRC clinical therapy.

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Silencing of lncRNA MIR497HG via CRISPR/Cas13d Induces Bladder Cancer Progression Through Promoting the Crosstalk Between Hippo/Yap and TGF-β/Smad Signaling

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2020.616768 ◽

2020 ◽

Vol 7 ◽

Author(s):

Changshui Zhuang ◽

Ying Liu ◽

Shengqiang Fu ◽

Chaobo Yuan ◽

Jingwen Luo ◽

...

Keyword(s):

Bladder Cancer ◽

Cell Line ◽

Cancer Progression ◽

Molecular Mechanisms ◽

Transforming Growth Factor ◽

Transforming Growth Factor Β ◽

Pathological Process ◽

The Cancer Genome Atlas ◽

Migration And Invasion

A subset of long non-coding RNAs (lncRNAs), categorized as miRNA-host gene lncRNAs (lnc-miRHGs), is processed to produce miRNAs and involved in cancer progression. This work aimed to investigate the influences and the molecular mechanisms of lnc-miRHGs MIR497HG in bladder cancer (BCa). The miR-497 and miR-195 were derived from MIR497HG. We identified that lnc-miRHG MIR497HG and two harbored miRNAs, miR-497 and miR-195, were downregulated in BCa by analyzing The Cancer Genome Atlas and our dataset. Silencing of MIR497HG by CRISPR/Cas13d in BCa cell line 5637 promoted cell growth, migration, and invasion in vitro. Conversely, overexpression of MIR497HG suppressed cell progression in BCa cell line T24. MiR-497/miR-195 mimics rescued significantly the oncogenic roles of knockdown of MIR497HG by CRISPR/Cas13d in BCa. Mechanistically, miR-497 and miR-195 co-ordinately suppressed multiple key components in Hippo/Yap and transforming growth factor β signaling and particularly attenuated the interaction between Yap and Smad3. In addition, E2F4 was proven to be critical for silencing MIR497HG transcription in BCa cells. In short, we propose for the first time to reveal the function and mechanisms of MIR497HG in BCa. Blocking the pathological process may be a potential strategy for the treatment of BCa.

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CircRNA_0058063 functions as a ceRNA in bladder cancer progression via targeting miR-486-3p/FOXP4 axis

10.21203/rs.2.17516/v2 ◽

2019 ◽

Author(s):

Haote Liang ◽

Hang Huang ◽

Yeping Li ◽

Yongyong Lu ◽

Tingyu Ye

Keyword(s):

Bladder Cancer ◽

Cancer Progression ◽

Luciferase Reporter ◽

Circular Rnas ◽

Aberrant Expression ◽

Normal Tissues ◽

Tumorigenesis And Progression ◽

Rna Immunoprecipitation ◽

Reporter Assays ◽

Proliferation And Invasion

Abstract Emerging evidences have uncovered critical regulatory roles of circular RNAs (circRNAs) function as dynamic scaffolding molecules in tumorigenesis and progression. However, the aberrant expression and clinical significance of hsa_circ_0058063 (circRNA_0058063) in bladder cancer (BC) remain poorly understood. circRNA expression was analyzed via a microarray in cancerous tissue and non-carcinoma tissues. Luciferase reporter assays and RNA immunoprecipitation (RIP) were both conducted to uncover the function of circRNA_0058063 in BC. circRNA_0058063 was overexpressed in BC tissues compared to adjacent normal tissues. Knockdown of circRNA_0058063 dramatically decreased cell proliferation and invasion, and promoted apoptosis in 5637 and BIU-87 cell lines. Furthermore, mechanistic investigations showed that circRNA_0058063 and FOXP4 could directly bind to miR-486-3p, demonstrating that circRNA_0058063 regulated FOXP4 expression by competitively binding to miR-486-3p. Taken together, circRNA_0058063 functions by sponging miR-486-3p in BC progression, which could be act as a new biomarker and further developed to be a therapeutic target in BC.

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Circular RNA hsa_circ_0081343 promotes trophoblast cell migration and invasion and inhibits trophoblast apoptosis by regulating miR-210-5p/DLX3 axis

10.21203/rs.3.rs-361692/v1 ◽

2021 ◽

Author(s):

Jiansheng Xie ◽

Hui Wang ◽

Caiqun Luo ◽

Xiaoxia Wu ◽

Jianming Zhang ◽

...

Keyword(s):

Luciferase Activity ◽

Circular Rna ◽

Extravillous Trophoblast ◽

Migration And Invasion ◽

Circular Rnas ◽

Protein Levels ◽

Apoptosis Protein ◽

Luciferase Activity Assay ◽

Rna Immunoprecipitation

Abstract Background: Various circular RNAs (circRNAs) are dysregulated in the placenta of fetal growth restriction fetuses, but their role and regulatory mechanisms have not been fully elucidated. Herein, we aimed to elucidate the role of hsa_circ_0081343 in regulating the migration, invasion, and apoptosis in the human extravillous trophoblast HTR-8 cells.Methods: circRNA and miRNA levels were examined using quantitative real-time PCR (RT-PCR). Overexpression plasmid constructs and siRNA were used to overexpress and knockdown hsa_circ_0081343, respectively. Transwell assay and flow cytometry analysis were performed to evaluate the effect of hsa_circ_0081343 or miR-210-5p on migration, invasion, and apoptosis. Protein levels were analyzed using western blot. Dual luciferase activity assay and anti-AGO2 RNA immunoprecipitation (RIP) assays were performed to identify the relationship between miR-210-5p and hsa_circ_0081343.Results: Hsa_circ_0081343 expression was significantly downregulated in 37 FGR placental tissues as compared to healthy placental control tissues. Hsa_circ_0081343 overexpression possibly inhibits apoptosis by downregulating the expression of cleaved caspase 3 and caspase 9 and alleviates the migration and invasion of HTR-8 cells by inducing the expression of MMP2 and MMP9. The dual luciferase activity and anti-AGO2 RIP assay results showed that hsa_circ_0081343 binds to miR-210-5p. miR-210-5p overexpression eliminated the effect of hsa_circ_0081343 overexpression in HTR-8 cells. Finally, DLX3 was identified as a direct target of miR-210-5p. Conclusions: Hsa_circ_0081343 regulates the migration, invasion, and apoptosis of HTR-8 cells via the hsa-miR-210-5p/DLX3 axis. Thus, hsa_circ_0081343 plays a key role in the etiology and pathogenesis of FGR implicating its importance as a novel candidate for targeted FGR therapy.

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