Role of ANKHD1/LINC00346/ZNF655 Feedback Loop in Regulating the Glioma Angiogenesis via Staufen1-Mediated mRNA Decay

Structural basis of the Integrator complex assembly and association with transcription factors

Integrator is a multi-subunit protein complex responsible for premature transcription termination of coding and non-coding RNAs. This is achieved via two enzymatic activities, RNA endonuclease and protein phosphatase, acting on the promoter-proximally paused RNA polymerase Ⅱ (RNAPⅡ). Yet, it remains unclear how Integrator assembly and recruitment are regulated and what the functions of many of its core subunits are. Here, we report the structures of two human Integrator sub-complexes: INTS10/13/14/15 and INTS5/8/10/15, and an integrative model of the fully assembled Integrator bound to the RNAPⅡ paused elongating complex (PEC). An in silico protein-protein interaction screen of over 1,500 human transcription factors (TFs) identified ZNF655 as a direct interacting partner of INTS13 within the fully assembled Integrator. We propose a model wherein INTS13 acts as a platform for the recruitment of TFs that could modulate the stability of the Integrator's association at specific loci and regulate transcription attenuation of the target genes.

The pathogenesis mechanism and potential clinical value of lncRNA in gliomas

Glioma is the most common malignant tumor in the central nervous system, and its unique pathogenesis often leads to poor treatment outcomes and prognosis. In 2021, the World Health Organization (WHO) divided gliomas into five categories based on their histological characteristics and molecular changes. Non-coding RNA is a type of RNA that does not encode proteins but can exert biological functions at the RNA level, and long non-coding RNA (lncRNA) is a type of non-coding RNA with a length exceeding 200 nt. It is controlled by various transcription factors and plays an indispensable role in the regulatory processes in various cells. Numerous studies have confirmed that the dysregulation of lncRNA is critical in the pathogenesis, progression, and malignancy of gliomas. Therefore, this article reviews the proliferation, apoptosis, invasion, migration, angiogenesis, immune regulation, glycolysis, stemness, and drug resistance changes caused by the dysregulation of lncRNA in gliomas, and summarizes their potential clinical significance in gliomas.

Regulation of inflammatory response by LINC00346 via miR-25-3p-mediated modulation of the PTEN/PI3K/AKT/NF-κB pathway

Long intergenic non-coding RNA 346 (LINC00346) has been reported to be involved in the development of atherosclerosis and specific cancers by affecting signaling pathways. However, its function in inflammation has not been thoroughly studied. Therefore, its expression pattern and function were determined in the human macrophage-like cell line THP-1. Lipopolysaccharide (LPS) treatment induced the expression of LINC00346. LPS-induced NF-κB activation and proinflammatory cytokine expression were suppressed or enhanced by the overexpression or knockdown of LINC00346, respectively. Analyses using dual luciferase assay and decoy RNAs that could block RNA-RNA interactions indicated that LINC00346 improves phosphatase and tensin homolog (PTEN) expression by sponging miR-25-3p. Subsequently, PTEN suppresses phosphoinositide-3 kinase (PI3K)-mediated conversion of phosphatidylinositol-4,5-bisphosphate (PIP2) into phosphatidylinositol-3,4,5-trisphosphate (PIP3) as well as consequent activation of protein kinase B (AKT) and NF-κB. Interestingly, database analysis revealed that the expression levels of LINC00346 and PTEN were simultaneously decreased in breast cancer tissues. Further analyses conducted using a breast cancer cell line, MDA-MB-231, confirmed the functional relationship among LINC00346, miR-25-3p, and PTEN in LPS-induced activation of NF-κB. These results indicate that miR-25-3p-sponging activity of LINC00346 affects the balance between PTEN and PI3K as well as the downstream activation of AKT/NF-κB pathway in inflammatory conditions.

Zinc finger Protein207 orchestrates glioma migration through regulation of epithelial-mesenchymal transition

BACKGROUND

Glioma represents the predominant primary malignant brain tumor. For several years, molecular profiling has been instrumental in the management and therapeutic stratification of glioma, providing a deeper understanding of its biological complexity. Accumulating evidence unveils the putative involvement of zinc finger proteins (ZNFs) in cancer. This study aimed to elucidate the role and significance of ZNF207 in glioma.

METHODS

Utilizing online data such as The Cancer Genome Atlas (TCGA), the Chinese Glioma Genome Atlas (CGGA), the Genotype-Tissue Expression (GTEx) project, the Clinical Proteomic Tumor Analysis Consortium (CPTAC), and the Human Protein Atlas (HPA) databases, in conjunction with bioinformatics methodologies including GO, KEGG, GSEA, CIBERSORT immune cell infiltration estimation, and protein-protein interaction (PPI) analysis, enabled a comprehensive exploration of ZNF207's involvement in gliomagenesis. Immunohistochemistry and RT-PCR techniques were employed to validate the expression level of ZNF207 in glioma samples. Subsequently, the biological effects of ZNF207 on glioma cells were explored through in vitro assays.

RESULTS

Our results demonstrate elevated expression of ZNF207 in gliomas, correlating with unfavorable patient outcomes. Stratification analyses were used to delineate the prognostic efficacy of ZNF207 in glioma with different clinicopathological characteristics. Immunocorrelation analysis revealed a significant association between ZNF207 expression and the infiltration levels of T helper cells, macrophages, and natural killer (NK) cells. Utilizing ZNF207 expression and clinical features, we constructed an OS prediction model and displayed well discrimination with a C-index of 0.861. Moreover, the strategic silencing of ZNF207 attenuated glioma cell advancement, evidenced by diminished cellular proliferation, weakened cell tumorigenesis, augmented apoptotic activity, and curtailed migratory capacity alongside the inhibition of the epithelial-mesenchymal transition (EMT) pathway.

CONCLUSIONS

ZNF207 may identify as a prospective biomarker and therapeutic candidate for glioma prevention, providing valuable insights into understanding glioma pathogenesis and treatment strategies.

Insights into the roles of non-coding RNAs and angiogenesis in glioblastoma: An overview of current research and future perspectives

Glioblastoma (GBM) is a highly aggressive type of primary brain cancer with a poor prognosis, and despite intensive research, survival rates have not significantly improved. Non-coding RNAs (ncRNAs) are emerging as critical regulators of GBM pathogenesis, including angiogenesis, which is essential for tumor growth and invasion. MicroRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) have been identified as regulators of angiogenesis in GBM. miRNAs such as miR-21, miR-10b, and miR-26a promote angiogenesis by targeting anti-angiogenic factors, while lncRNAs such as H19 and MALAT1 inhibit angiogenesis by regulating pro-angiogenic factors. CircRNAs, such as circSMARCA5 and circBACH2, also regulate angiogenesis through various mechanisms. Similarly, signaling pathways such as the vascular endothelial growth factor (VEGF) pathway play critical roles in angiogenesis and have been targeted for GBM therapy. However, resistance to anti-angiogenic therapies is a significant obstacle in clinical practice. Developing novel therapeutic strategies targeting ncRNAs and angiogenesis is a promising approach for GBM. Potential targets include miRNAs, lncRNAs, circRNAs, and downstream signaling pathways that regulate angiogenesis. This review highlights the critical roles of ncRNAs and angiogenesis in GBM pathogenesis and the potential for new therapeutic strategies targeting these pathways to improve the prognosis and quality of life for GBM patients.

Evaluating the Molecular Properties and Function of ANKHD1, and Its Role in Cancer

Ankyrin repeat and single KH domain-containing protein 1 (ANKHD1) is a large, scaffolding protein composed of two stretches of ankyrin repeat domains that mediate protein-protein interactions and a KH domain that mediates RNA or single-stranded DNA binding. ANKHD1 interacts with proteins in several crucial signalling pathways, including receptor tyrosine kinase, JAK/STAT, mechanosensitive Hippo (YAP/TAZ), and p21. Studies into the role of ANKHD1 in cancer cell lines demonstrate a crucial role in driving uncontrolled cellular proliferation and growth, enhanced tumorigenicity, cell cycle progression through the S phase, and increased epithelial-to-mesenchymal transition. Furthermore, at a clinical level, the increased expression of ANKHD1 has been associated with greater tumour infiltration, increased metastasis, and larger tumours. Elevated ANKHD1 resulted in poorer prognosis, more aggressive growth, and a decrease in patient survival in numerous cancer types. This review aims to gather the current knowledge about ANKHD1 and explore its molecular properties and functions, focusing on the protein's role in cancer at both a cellular and clinical level.

Insights into the Role of LncRNAs and miRNAs in Glioma Progression and Their Potential as Novel Therapeutic Targets

Accumulating evidence supports that both long non-coding and micro RNAs (lncRNAs and miRNAs) are implicated in glioma tumorigenesis and progression. Poor outcome of gliomas has been linked to late-stage diagnosis and mostly ineffectiveness of conventional treatment due to low knowledge about the early stage of gliomas, which are not possible to observe with conventional diagnostic approaches. The past few years witnessed a revolutionary advance in biotechnology and neuroscience with the understanding of tumor-related molecules, including non-coding RNAs that are involved in the angiogenesis and progression of glioma cells and thus are used as prognostic biomarkers as well as novel therapeutic targets. The emerging research on lncRNAs and miRNAs highlights their crucial role in glioma progression, offering new insights into the disease. These non-coding RNAs hold significant potential as novel therapeutic targets, paving the way for innovative treatment approaches against glioma. This review encompasses a comprehensive discussion about the role of lncRNAs and miRNAs in gene regulation that is responsible for the promotion or the inhibition of glioma progression and collects the existing links between these key cancer-related molecules.

ZNF655 mediated by LINC01210/miR-124-3p axis promotes the progression of gastric cancer

Gastric cancer (GC) is a common malignant tumor that usually originates from the epithelium of the gastric mucosa. ZNF655 was a suppressor gene of many cancers. However, the mechanism of ZNF655 in GC remains unknown. Quantitative polymerase chain reaction was used to assess the expression of ZNF655, LINC01210, and miR-124-3p. Western blotting was used to monitor ZNF655 protein expression. MTT, clone formation, transwell, and flow cytometry were all used to investigate the functions of GC cells. The interactions between ZNF655, LINC01210, and miR-124-3p were confirmed using the dual-luciferase reporter gene assay and the RIP assay. ZNF655 was highly expressed in GC cells. ZNF655 knockdown reduced GC cell viability, proliferation, migration, invasion, and induced apoptosis. The level of miR-124-3p was significantly reduced in GC cells. Besides, miR-124-3p targeted ZNF655 and inhibited its expression. MiR-124-3p mimics inhibited GC cell progression, but ZNF655 overexpression reversed these effects. Moreover, LINC01210 was found to be highly expressed in GC cells and to be able to sponge miR-124-3p. Furthermore, inhibiting miR-124-3p or increasing ZNF655 could counteract the effects of LINC01210 knockdown on GC cell development. Finally, ZNF655 promoted GC cell progression and was regulated by the LINC01210/miR-124-3p axis.

Identification of Prognostic Signature of Necroptosis-Related lncRNAs and Molecular Subtypes in Glioma

Background

In tumor progression and epigenetic regulation, long non-coding RNA (lncRNA) and necroptosis are crucial regulators. However, in glioma microenvironment, the role of necroptosis-related lncRNAs (NRLs) remains unknown.

Method

In this study, the RNA-seq and clinical annotation of glioma patients were analyzed using the Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) databases. To investigate prognosis and tumor microenvironment of NRLs in gliomas, we conducted a prediction model based on the training cohort. The accuracy of the model was verified in the verification cohort.

Results

A signature composed of 13 NRLs was identified, and all glioma patients were divided into two groups. We found that each group has unique survival outcomes, biological behaviors, and immune infiltrating status. The necroptosis-related lncRNA signature (NRLS) model was found to be an independent risk factor in multivariate Cox analysis. Immunosuppressive microenvironment was positively correlated with the high-risk group. Due to significantly different IC50 between risk groups, NRLS could be used as a guide for chemotherapeutic treatment. Further, the entire cohort was divided into two clusters depending on NRLs. Consensus clustering method and the risk scoring system were basically similar. Survival probability was higher in Cluster 2, while Cluster 1 has stronger immunologic infiltration.

Conclusion

The predictive signature could be a prognostic factor independently and serve to detect the role of NRLs in glioma immunotherapy response.

ZNF655 accelerates progression of pancreatic cancer by promoting the binding of E2F1 and CDK1

Pancreatic cancer has an extremely terrible prognosis and is a common cause of cancer death. In this study, the clinic value, biological function and underlying mechanisms of Zinc finger protein 655 (ZNF655) in human pancreatic cancer were evaluated. The expression level of ZNF655 in pancreatic cancer was determined by immunohistochemistry (IHC) staining. The biological effects of ZNF655 in pancreatic cancer cells was investigated by loss/gain-of-function assays in vitro and in vivo. The downstream molecular mechanism of ZNF655 was explored using co-immunoprecipitation (Co-IP), dual-luciferase reporter and chromatin immunoprecipitation (Ch-IP). ZNF655 expression was significantly elevated in human pancreatic cancer and possessed clinical value in predicting poor prognosis. Functionally, ZNF655 knockdown inhibited the biological progression of pancreatic cancer cells, which was characterized by weaken proliferation, enhanced apoptosis, arrested cell cycle in G2, impeded migration, and suppressed tumor growth. Mechanistically, ZNF655 played an important role in promoting the binding of E2F transcription factor 1 (E2F1) to the cyclin-dependent kinase 1 (CDK1) promoter. Furthermore, knockdown of CDK1 alleviated the promoting effects of ZNF655 overexpression in pancreatic cancer cells. The promotive role of ZNF655 in pancreatic cancer via CDK1 was determined, which drew further interest regarding its clinical application as a promising therapeutic target.

Evolving Insights Into the Biological Function and Clinical Significance of Long Noncoding RNA in Glioblastoma

Glioblastoma (GBM) is one of the most prevalent and aggressive cancers worldwide. The overall survival period of GBM patients is only 15 months even with standard combination therapy. The absence of validated biomarkers for early diagnosis mainly accounts for worse clinical outcomes of GBM patients. Thus, there is an urgent requirement to characterize more biomarkers for the early diagnosis of GBM patients. In addition, the detailed molecular basis during GBM pathogenesis and oncogenesis is not fully understood, highlighting that it is of great significance to elucidate the molecular mechanisms of GBM initiation and development. Recently, accumulated pieces of evidence have revealed the central roles of long noncoding RNAs (lncRNAs) in the tumorigenesis and progression of GBM by binding with DNA, RNA, or protein. Targeting those oncogenic lncRNAs in GBM may be promising to develop more effective therapeutics. Furthermore, a better understanding of the biological function and underlying molecular basis of dysregulated lncRNAs in GBM initiation and development will offer new insights into GBM early diagnosis and develop novel treatments for GBM patients. Herein, this review builds on previous studies to summarize the dysregulated lncRNAs in GBM and their unique biological functions during GBM tumorigenesis and progression. In addition, new insights and challenges of lncRNA-based diagnostic and therapeutic potentials for GBM patients were also introduced.

Long Non Coding RNA Based Regulation of Cerebrovascular Endothelium

The rapid and high throughput discovery of long non coding RNAs (lncRNAs) has far outstripped the functional annotation of these novel transcripts in their respective cellular contexts. The cells of the blood brain barrier (BBB), especially the cerebrovascular endothelial cells (CVECs), are strictly regulated to maintain a controlled state of homeostasis for undisrupted brain function. Several key pathways are understood in CVEC function that lead to the development and maintenance of their barrier properties, the dysregulation of which leads to BBB breakdown and neuronal injury. Endothelial lncRNAs have been discovered and functionally validated in the past decade, spanning a wide variety of regulatory mechanisms in health and disease. We summarize here the lncRNA-mediated regulation of established pathways that maintain or disrupt the barrier property of CVECs, including in conditions such as ischemic stroke and glioma. These lncRNAs namely regulate the tight junction assembly/disassembly, angiogenesis, autophagy, apoptosis, and so on. The identification of these lncRNAs suggests a less understood mechanistic layer, calling for further studies in appropriate models of the blood brain barrier to shed light on the lncRNA-mediated regulation of CVEC function. Finally, we gather various approaches for validating lncRNAs in BBB function in human organoids and animal models and discuss the therapeutic potential of CVEC lncRNAs along with the current limitations.

Crucial Roles of miR-625 in Human Cancer

Genetic and epigenetic characteristics are core factors of cancer. MicroRNAs (miRNAs) are small non-coding RNAs which regulate gene expression at the post-transcriptional level via binding to corresponding mRNAs. Recently, increasing evidence has proven that miRNAs regulate the occurrence and development of human cancer. Here, we mainly review the abnormal expression of miR-625 in a variety of cancers. In summarizing the role and potential molecular mechanisms of miR-625 in various tumors in detail, we reveal that miR-625 is involved in a variety of biological processes, such as cell proliferation, invasion, migration, apoptosis, cell cycle regulation, and drug resistance. In addition, we discuss the lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA networks and briefly explain the specific mechanisms of competing endogenous RNAs. In conclusion, we reveal the potential value of miR-625 in cancer diagnosis, treatment, and prognosis and hope to provide new ideas for the clinical application of miR-625.

ZNF655 Promotes the Progression of Glioma Through Transcriptional Regulation of AURKA

Objectives

Glioma has a high degree of malignancy, strong invasiveness, and poor prognosis, which is always a serious threat to human health. Previous studies have reported that C2H2 zinc finger (ZNF) protein is involved in the progression of various cancers. In this study, the clinical significance, biological behavior, and molecule mechanism of ZNF655 in glioma were explored.

Methods

The expression of ZNF655 in glioma and its correlation with prognosis were analyzed through public datasets and immunohistochemical (IHC) staining. The shRNA-mediated ZNF655 knockdown was used to explore the effects of ZNF655 alteration on the phenotypes and tumorigenesis of human glioma cell lines. Chromatin immunoprecipitation (ChIP)-qPCR and luciferase reporter assays were performed to determine the potential mechanism of ZNF655 regulating Aurora kinase A (AURKA).

Results

ZNF655 was abundantly expressed in glioma tissue and cell lines SHG-44 and U251. Knockdown of suppressed the progression of glioma cells, which was characterized by reduced proliferation, enhanced apoptosis, cycle repression in G2, inhibition of migration, and weakened tumorigenesis. Mechanistically, transcription factor ZNF655 activated the expression of AURKA by directly binding to the promoter of AURKA. In addition, downregulation of AURKA partially reversed the promoting effects of overexpression of ZNF655 on glioma cells.

Conclusions

ZNF655 promoted the progression of glioma by binding to the promoter of AURKA, which may be a promising target for molecular therapy.

The feedback loop of ANKHD1/lncRNA MALAT1/YAP1 strengthens the radioresistance of CRC by activating YAP1/AKT signaling

Innate radioresistance substantially limits the effectiveness of radiotherapy for colorectal cancer (CRC); thus, a strategy to enhance the radiosensitivity of CRC is urgently needed. Herein, we reported that ankyrin repeat and KH domain containing 1 (ANKHD1) serves as a key regulator of radioresistance in CRC. ANKHD1 was highly expressed in CRC tissues and was highly correlated with Yes-associated protein 1 (YAP1) in CRC. Our results first revealed that ANKHD1 knockdown could increase the radiosensitivity of CRC by regulating DNA-damage repair, both in vitro and in vivo. Furthermore, the interactive regulation between ANKHD1 or YAP1 and lncRNA MALAT1 was revealed by RIP and RNA pull-down assays. Moreover, our results also demonstrated that MALAT1 silencing can radiosensitize CRC cells to IR through YAP1/AKT axis, similar to ANKHD1 silencing. Taken together, we report a feedback loop of ANKHD1/MALAT1/YAP1 that synergistically promotes the transcriptional coactivation of YAP1 and in turn enhances the radioresistance of CRC by regulating DNA-damage repair, probably via the YAP1/AKT axis. Our results suggested that targeting the YAP1/AKT axis downstream of ANKHD1/MALAT1/YAP1 may enhance the radiosensitivity of CRC.

New Insights into LINC00346 and its Role in Disease

Accumulating evidence has shown that long intergenic non-protein-coding RNA 346 (LINC00346) functions as an oncogene in the tumorigenesis of several cancers. The expression level of LINC00346 has been shown to be obviously correlated with prognosis, lymphoma metastasis, histological grade, TNM stage, tumor size and pathologic stage. LINC00346 has been found to regulate specific cellular functions by interacting with several molecules and signaling pathways. In this review, we summarize recent evidence concerning the role of LINC00346 in the occurrence and development of diseases. We also discuss the potential clinical utility of LINC00346, thereby providing new insight into the diagnosis and treatment of diseases. In addition, we further discuss the potential clinical utility of LINC00346 in the diagnosis, prognostication, and treatment of diseases.

LncRNAs and the Angiogenic Switch in Cancer: Clinical Significance and Therapeutic Opportunities

Angiogenesis is one of the hallmarks of cancer, and the establishment of new blood vessels is vital to allow for a tumour to grow beyond 1-2 mm in size. The angiogenic switch is the term given to the point where the number or activity of the pro-angiogenic factors exceeds that of the anti-angiogenic factors, resulting in the angiogenic process proceeding, giving rise to new blood vessels accompanied by increased tumour growth, metastasis, and potential drug resistance. Long noncoding ribonucleic acids (lncRNAs) have been found to play a role in the angiogenic switch by regulating gene expression, transcription, translation, and post translation modification. In this regard they play both anti-angiogenic and pro-angiogenic roles. The expression levels of the pro-angiogenic lncRNAs have been found to correlate with patient survival. These lncRNAs are also potential drug targets for the development of therapies that will inhibit or modify tumour angiogenesis. Here we review the roles of lncRNAs in regulating the angiogenic switch. We cover specific examples of both pro and anti-angiogenic lncRNAs and discuss their potential use as both prognostic biomarkers and targets for the development of future therapies.

High Level of Staufen1 Expression Confers Longer Recurrence Free Survival to Non-Small Cell Lung Cancer Patients by Promoting THBS1 mRNA Degradation

Stau1 is a pluripotent RNA-binding protein that is responsible for the post-transcriptional regulation of a multitude of transcripts. Here, we observed that lung cancer patients with a high Stau1 expression have a longer recurrence free survival. Strikingly, Stau1 did not impair cell proliferation in vitro, but rather cell migration and cell adhesion. In vivo, Stau1 depletion favored tumor progression and metastases development. In addition, Stau1 depletion strongly impaired vessel maturation. Among a panel of candidate genes, we specifically identified the mRNA encoding the cell adhesion molecule Thrombospondin 1 (THBS1) as a new target for Staufen-mediated mRNA decay. Altogether, our results suggest that regulation of THBS1 expression by Stau1 may be a key process involved in lung cancer progression.

Pseudogene RPL32P3 regulates the blood-tumor barrier permeability via the YBX2/HNF4G axis

The existence of the blood–tumor barrier (BTB) severely hinders the transport of anti-tumor drugs to brain tumor tissues. Selectively opening BTB is of great significance to improve the chemotherapy effect of glioma. Pseudogenes have been recognized as important regulators in various biologic processes. In this study, we identified that ribosomal protein L32 pseudogene 3 (RPL32P3) was highly expressed in glioma-exposed endothelial cells (GECs). Knockdown of RPL32P3 decreased the expression of tight junction-related proteins (TJPs) and increased BTB permeability. Subsequent analysis of the underlying mechanism indicated that RPL32P3 recruited lysine methyltransferase 2 A (KMT2A) to the Y-box binding protein 2 (YBX2) promoter region and mediated H3K4me3 to promote YBX2 transcription. Highly expressed YBX2 bound and stabilized hepatocyte nuclear factor 4 gamma (HNF4G) mRNA. Highly expressed HNF4G directly bound to the promoters of TJPs ZO-1, occludin and claudin-5 to promote their transcriptional activities and regulated BTB permeability. The simultaneous knockdown of RPL32P3, YBX2, and HNF4G combined with doxorubicin (DOX) increased the apoptosis of glioma cells. In conclusion, the current study indicated that RPL32P3 knockdown increased BTB permeability through the YBX2/HNF4G pathway. These findings may provide new targets for the comprehensive treatment of glioma.

Non-Coding RNAs in Glioma Microenvironment and Angiogenesis

Glioma, especially glioblastoma, is the most common and lethal brain tumor. In line with the complicated vascularization processes and the strong intratumoral heterogeneity, tumor-associated blood vessels in glioma are regulated by multiple types of cells through a variety of molecular mechanisms. Components of the tumor microenvironment, including tumor cells and tumor-associated stromata, produce various types of molecular mediators to regulate glioma angiogenesis. As critical regulatory molecules, non-coding RNAs (ncRNAs) inside cells or secreted to the tumor microenvironment play essential roles in glioma angiogenesis. In this review, we briefly summarize recent studies about the production, delivery, and functions of ncRNAs in the tumor microenvironment, as well as the molecular mechanisms underlying the regulation of angiogenesis by ncRNAs. We also discuss the ncRNA-based therapeutic strategies in the anti-angiogenic therapy for glioma treatment.

Long noncoding RNA SNHG4: a novel target in human diseases

Recently, long noncoding RNAs (lncRNAs) have attracted great attention from researchers. LncRNAs are non-protein-coding RNAs of more than 200 nucleotides in length. Multiple studies have been published on the relationship between lncRNA expression and the progression of human diseases. LncRNA small nucleolar RNA host gene 4 (SNHG4), a member of the lncRNA SNHG family, is abnormally expressed in a variety of human diseases, including gastric cancer, renal cell carcinoma, glioblastoma, neuroblastoma, prostate cancer, colorectal cancer, osteosarcoma, cervical cancer, liver cancer, lung cancer, non-small-cell lung cancer, neonatal pneumonia, diabetic retinopathy, neuropathic pain, acute cerebral infarction, acute myeloid leukaemia, and endometriosis. In this paper, the structure of SNHG4 is first introduced, and then studies in humans, animal models and cells are summarized to highlight the expression and function of SNHG4 in the above diseases. In addition, the specific mechanism of SNHG4 as a competing endogenous RNA (ceRNA) is discussed. The findings indicate that SNHG4 can be used as a biomarker for disease prognosis evaluation and as a potential target for disease diagnosis and treatment.

Alu RNA and their roles in human disease states

Alu RNA are implicated in the poor prognosis of several human disease states. These RNA are transcription products of primate specific transposable elements called Alu elements. These elements are extremely abundant, comprising over 10% of the human genome, and 100 to 1000 cytoplasmic copies of Alu RNA per cell. Alu RNA do not have a single universal functional role aside from selfish self-propagation. Despite this, Alu RNA have been found to operate in a diverse set of translational and transcriptional mechanisms. This review will focus on the current knowledge of Alu RNA involved in human disease states and known mechanisms of action. Examples of Alu RNA that are transcribed in a variety of contexts such as introns, mature mRNA, and non-coding transcripts will be discussed. Past and present challenges in studying Alu RNA, and the future directions of Alu RNA in basic and clinical research will also be examined.

Long non-coding RNAs and circular RNAs in tumor angiogenesis: From mechanisms to clinical significance

Long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) execute a wide array of functions in physiological and pathological processes, including tumor progression. Angiogenesis, an elaborate multistep process driving new blood vessel formation, accelerates cancer progression by supplying nutrients and energy. Dysregulated lncRNAs and circRNAs can reportedly impact cancer progression by influencing angiogenesis. However, the expanding landscape of lncRNAs and circRNAs in tumor progression-dependent angiogenesis remains largely unknown. This review summarizes the major functions of angiogenic lncRNAs (Angio-LncRs) and angiogenic circRNAs (termed Angio-CircRs) and their cancer mechanisms. Moreover, we highlight the commonalities of lncRNAs and circRNAs in epigenetic, transcriptional, and post-transcriptional regulation as well as illustrate how Angio-LncRs and Angio-CircRs induce cancer onset and progression. We also discuss their potential clinical applications in diagnosis, prognosis, and anti-angiogenic therapies.

NF-κB-activated SPRY4-IT1 promotes cancer cell metastasis by downregulating TCEB1 mRNA via Staufen1-mediated mRNA decay

Previous study demonstrated that most long non-coding RNAs (lncRNAs) function as competing endogenous RNAs or molecular sponges to negatively modulate miRNA and regulate tumor development. However, the molecular mechanisms of lncRNAs in cancer are not fully understood. Our study describes the role of the lncRNA SPRY4 intronic transcript 1 (SPRY4-IT1) in cancer metastasis by mechanisms related to Staufen1 (STAU1)-mediated mRNA decay (SMD). Briefly, we found that, high SPRY4-IT1 expression was associated with aggressiveness and poor outcome in human colorectal, breast and ovarian cancer tissues. In addition, functional assays revealed that SPRY4-IT1 significantly promoted colorectal, breast and ovarian cancer metastasis in vitro and in vivo. Mechanistically, microarray analyses identified several differentially-expressed genes upon SPRY4-IT1 overexpression in HCT 116 colorectal cancer cells. Among them, the 3'-UTR of transcription elongation factor B subunit 1 (TCEB1) mRNA can base-pair with the Alu element in the 3'-UTR of SPRY4-IT1. Moreover, SPRY4-IT1 was found to bind STAU1, promote STAU1 recruitment to the 3'-UTR of TCEB1 mRNA, and affect TCEB1 mRNA stability and expression, resulting in hypoxia-inducible factor 1α (HIF-1α) upregulation, and thereby affecting cancer cell metastasis. In addition, STAU1 depletion abrogated TCEB1 SMD and alleviated the pro-metastatic effect of SPRY4-IT1 overexpression. Significantly, we revealed that SPRY4-IT1 is also transactivated by NF-κB/p65, which activates SPRY4-IT1 to inhibit TCEB1 expression, and subsequently upregulate HIF-1α. In conclusion, our results highlight a novel mechanism of cytoplasmic lncRNA SPRY4-IT1 in which SPRY4-IT1 affecting TCEB1 mRNA stability via STAU1-mediated degradation during cancer metastasis.

Roles of Long Noncoding RNAs in Conferring Glioma Progression and Treatment

Accompanying the development of biomedicine, our knowledge of glioma, one of the most common primary intracranial carcinomas, is becoming more comprehensive. Unfortunately, patients with glioblastoma (GBM) still have a dismal prognosis and a high relapse rate, even with standard combination therapy, namely, surgical resection, postoperative radiotherapy and chemotherapy. The absence of validated biomarkers is responsible for the majority of these poor outcomes, and reliable therapeutic targets are indispensable for improving the prognosis of patients suffering from gliomas. Identification of both precise diagnostic and accurate prognostic markers and promising therapeutic targets has therefore attracted considerable attention from researchers. Encouragingly, accumulating evidence has demonstrated that long noncoding RNAs (lncRNAs) play important roles in the pathogenesis and oncogenesis of various categories of human tumors, including gliomas. Nevertheless, the underlying mechanisms by which lncRNAs regulate diverse biological behaviors of glioma cells, such as proliferation, invasion and migration, remain poorly understood. Consequently, this review builds on previous studies to further summarize the progress in the field of lncRNA regulation of gliomas over recent years and addresses the potential of lncRNAs as diagnostic and prognostic markers and therapeutic targets.

The Staufen1-dependent cell cycle regulon or how a misregulated RNA-binding protein leads to cancer

In recent years, an increasing number of reports have linked the RNA-binding protein Staufen1 (STAU1) to the control of cell decision making. In non-transformed cells, STAU1 balances the expression of messenger RNA (mRNA) regulons that regulate differentiation and well-ordered cell division. Misregulation of STAU1 expression and/or functions changes the fragile balance in the expression of pro- and anti-proliferative and apoptotic genes and favours a novel equilibrium that supports cell proliferation and cancer development. The misregulation of STAU1 functions causes multiple coordinated modest effects in the post-transcriptional regulation of many RNA targets that code for cell cycle regulators, leading to dramatic consequences at the cellular level. The new tumorigenic equilibrium in STAU1-mediated gene regulation observed in cancer cells can be further altered by a slight increase in STAU1 expression that favours expression of pro-apoptotic genes and cell death. The STAU1-dependent cell cycle regulon is a good model to study how abnormal expression of an RNA-binding protein promotes cell growth and provides an advantageous selection of malignant cells in the first step of cancer development.

Glioma glycolipid metabolism: MSI2-SNORD12B-FIP1L1-ZBTB4 feedback loop as a potential treatment target

Abnormal energy metabolism, including enhanced aerobic glycolysis and lipid synthesis, is a well-established feature of glioblastoma (GBM) cells. Thus, targeting the cellular glycolipid metabolism can be a feasible therapeutic strategy for GBM. This study aimed to evaluate the roles of MSI2, SNORD12B, and ZBTB4 in regulating the glycolipid metabolism and proliferation of GBM cells. MSI2 and SNORD12B expression was significantly upregulated and ZBTB4 expression was significantly low in GBM tissues and cells. Knockdown of MSI2 or SNORD12B or overexpression of ZBTB4 inhibited GBM cell glycolipid metabolism and proliferation. MSI2 may improve SNORD12B expression by increasing its stability. Importantly, SNORD12B increased utilization of the ZBTB4 mRNA transcript distal polyadenylation signal in alternative polyadenylation processing by competitively combining with FIP1L1, which decreased ZBTB4 expression because of the increased proportion of the 3' untranslated region long transcript. ZBTB4 transcriptionally suppressed the expression of HK2 and ACLY by binding directly to the promoter regions. Additionally, ZBTB4 bound the MSI promoter region to transcriptionally suppress MSI2 expression, thereby forming an MSI2/SNORD12B/FIP1L1/ZBTB4 feedback loop to regulate the glycolipid metabolism and proliferation of GBM cells. In conclusion, MSI2 increased the stability of SNORD12B, which regulated ZBTB4 alternative polyadenylation processing by competitively binding to FIP1L1. Thus, the MSI2/SNORD12B/FIP1L1/ZBTB4 positive feedback loop plays a crucial role in regulating the glycolipid metabolism of GBM cells and provides a potential drug target for glioma treatment.

Noncoding RNAs Associated with Therapeutic Resistance in Pancreatic Cancer

Therapeutic resistance is an inevitable impediment towards effective cancer therapies. Evidence accumulated has shown that the signaling pathways and related factors are fundamentally responsible for therapeutic resistance via regulating diverse cellular events, such as epithelial-to-mesenchymal transition (EMT), stemness, cell survival/apoptosis, autophagy, etcetera. Noncoding RNAs (ncRNAs) have been identified as essential cellular components in gene regulation. The expression of ncRNAs is altered in cancer, and dysregulated ncRNAs participate in gene regulatory networks in pathological contexts. An in-depth understanding of molecular mechanisms underlying the modulation of therapeutic resistance is required to refine therapeutic benefits. This review presents an overview of the recent evidence concerning the role of human ncRNAs in therapeutic resistance, together with the feasibility of ncRNAs as therapeutic targets in pancreatic cancer.

Interaction Between LncRNA and UPF1 in Tumors

Long non-coding RNAs (LncRNAs) can bind to other proteins or RNAs to regulate gene expression, and its role in tumors has been extensively studied. A common RNA binding protein, UPF1, is also a key factor in a variety of RNA decay pathways. RNA decay pathways serve to control levels of particular RNA molecules. The expression of UPF1 is often dysregulated in tumors, an observation which suggests that UPF1 contributes to development of a variety of tumors. Herein, we review evidence from studies of fourteen lncRNAs interact with UPF1. The interaction between lncRNA and UPFI provide fundamental basis for cell transformation and tumorigenic growth.

Distinct roles for the RNA-binding protein Staufen1 in prostate cancer

BACKGROUND

Prostate cancer is one of the most common malignant cancers with the second highest global rate of mortality in men. During the early stages of disease progression, tumour growth is local and androgen-dependent. Despite treatment, a large percentage of patients develop androgen-independent prostate cancer, which often results in metastases, a leading cause of mortality in these patients. Our previous work on the RNA-binding protein Staufen1 demonstrated its novel role in cancer biology, and in particular rhabdomyosarcoma tumorigenesis. To build upon this work, we have focused on the role of Staufen1 in other forms of cancer and describe here the novel and differential roles of Staufen1 in prostate cancer.

METHODS

Using a cell-based approach, three independent prostate cancer cell lines with different characteristics were used to evaluate the expression of Staufen1 in human prostate cancer relative to control prostate cells. The functional impact of Staufen1 on several key oncogenic features of prostate cancer cells including proliferation, apoptosis, migration and invasion were systematically investigated.

RESULTS

We show that Staufen1 levels are increased in all human prostate cancer cells examined in comparison to normal prostate epithelial cells. Furthermore, Staufen1 differentially regulates growth, migration, and invasion in the various prostate cancer cells assessed. In LNCaP prostate cancer cells, Staufen1 regulates cell proliferation through mTOR activation. Conversely, Staufen1 regulates migration and invasion of the highly invasive, bone metastatic-derived, PC3 prostate cells via the activation of focal adhesion kinase.

CONCLUSIONS

Collectively, these results show that Staufen1 has a direct impact in prostate cancer development and further demonstrate that its functions vary amongst the prostate cancer cell types. Accordingly, Staufen1 represents a novel target for the development of much-needed therapeutic strategies for prostate cancer.

Emerging functions for ANKHD1 in cancer-related signaling pathways and cellular processes

ANKHD1 (ankyrin repeat and KH domain containing 1) is a large protein characterized by the presence of multiple ankyrin repeats and a K-homology domain. Ankyrin repeat domains consist of widely existing protein motifs in nature, they mediate protein-protein interactions and regulate fundamental biological processes, while the KH domain binds to RNA or ssDNA and is associated with transcriptional and translational regulation. In recent years, studies containing relevant information on ANKHD1 in cancer biology and its clinical relevance, as well as the increasing complexity of signaling networks in which this protein acts, have been reported. Among the signaling pathways of interest in oncology regulated by ANKHD1 are Hippo signaling, JAK/STAT, and STMN1. The scope of the present review is to survey the current knowledge and high-light future perspectives for ANKHD1 in the malignant phenotype of cancer cells, exploring biological, functional, and clinical reports of this protein in cancer.

Emerging functions for ANKHD1 in cancer-related signaling pathways and cellular processes

ANKHD1 (ankyrin repeat and KH domain containing 1) is a large protein characterized by the presence of multiple ankyrin repeats and a K-homology domain. Ankyrin repeat domains consist of widely existing protein motifs in nature, they mediate protein-protein interactions and regulate fundamental biological processes, while the KH domain binds to RNA or ssDNA and is associated with transcriptional and translational regulation. In recent years, studies containing relevant information on ANKHD1 in cancer biology and its clinical relevance, as well as the increasing complexity of signaling networks in which this protein acts, have been reported. Among the signaling pathways of interest in oncology regulated by ANKHD1 are Hippo signaling, JAK/STAT, and STMN1. The scope of the present review is to survey the current knowledge and highlight future perspectives for ANKHD1 in the malignant phenotype of cancer cells, exploring biological, functional, and clinical reports of this protein in cancer. [BMB Reports 2020; 53(8): 413-418].