TGF-β-activated lncRNA LINC00115 is a critical regulator of glioma stem-like cell tumorigenicity

Role of Extracellular Vesicles in the Progression of Brain Tumors

Brain tumors, and, in particular, glioblastoma (GBM), are among the most aggressive forms of cancer. In spite of the advancement in the available therapies, both diagnosis and treatments are still unable to ensure pathology-free survival of the GBM patients for more than 12-15 months. At the basis of the still poor ability to cope with brain tumors, we can consider: (i) intra-tumor heterogeneity; (ii) heterogeneity of the tumor properties when we compare different patients; (iii) the blood-brain barrier (BBB), which makes difficult both isolation of tumor-specific biomarkers and delivering of therapeutic drugs to the brain. Recently, it is becoming increasingly clear that cancer cells release large amounts of extracellular vesicles (EVs) that transport metabolites, proteins, different classes of RNAs, DNA, and lipids. These structures are involved in the pathological process and characterize any particular form of cancer. Moreover, EVs are able to cross the BBB in both directions. Starting from these observations, researchers are now evaluating the possibility to use EVs purified from organic fluids (first of all, blood and saliva), in order to obtain, through non-invasive methods (liquid biopsy), tumor biomarkers, and, perhaps, also for obtaining nanocarriers for the targeted delivering of drugs.

Cancer stem cells: advances in knowledge and implications for cancer therapy

Cancer stem cells (CSCs), a small subset of cells in tumors that are characterized by self-renewal and continuous proliferation, lead to tumorigenesis, metastasis, and maintain tumor heterogeneity. Cancer continues to be a significant global disease burden. In the past, surgery, radiotherapy, and chemotherapy were the main cancer treatments. The technology of cancer treatments continues to develop and advance, and the emergence of targeted therapy, and immunotherapy provides more options for patients to a certain extent. However, the limitations of efficacy and treatment resistance are still inevitable. Our review begins with a brief introduction of the historical discoveries, original hypotheses, and pathways that regulate CSCs, such as WNT/β-Catenin, hedgehog, Notch, NF-κB, JAK/STAT, TGF-β, PI3K/AKT, PPAR pathway, and their crosstalk. We focus on the role of CSCs in various therapeutic outcomes and resistance, including how the treatments affect the content of CSCs and the alteration of related molecules, CSCs-mediated therapeutic resistance, and the clinical value of targeting CSCs in patients with refractory, progressed or advanced tumors. In summary, CSCs affect therapeutic efficacy, and the treatment method of targeting CSCs is still difficult to determine. Clarifying regulatory mechanisms and targeting biomarkers of CSCs is currently the mainstream idea.

Hidden regulators: the emerging roles of lncRNAs in brain development and disease

Long non-coding RNAs (lncRNAs) have emerged as critical players in brain development and disease. These non-coding transcripts, which once considered as "transcriptional junk," are now known for their regulatory roles in gene expression. In brain development, lncRNAs participate in many processes, including neurogenesis, neuronal differentiation, and synaptogenesis. They employ their effect through a wide variety of transcriptional and post-transcriptional regulatory mechanisms through interactions with chromatin modifiers, transcription factors, and other regulatory molecules. Dysregulation of lncRNAs has been associated with certain brain diseases, including Alzheimer's disease, Parkinson's disease, cancer, and neurodevelopmental disorders. Altered expression and function of specific lncRNAs have been implicated with disrupted neuronal connectivity, impaired synaptic plasticity, and aberrant gene expression pattern, highlighting the functional importance of this subclass of brain-enriched RNAs. Moreover, lncRNAs have been identified as potential biomarkers and therapeutic targets for neurological diseases. Here, we give a comprehensive review of the existing knowledge of lncRNAs. Our aim is to provide a better understanding of the diversity of lncRNA structure and functions in brain development and disease. This holds promise for unravelling the complexity of neurodevelopmental and neurodegenerative disorders, paving the way for the development of novel biomarkers and therapeutic targets for improved diagnosis and treatment.

LINC00115 aggravates thyroid cancer progression by targeting miR-489-3p, which downregulates EVA1A to regulate the Hippo signaling pathway

LINC00115 has been documented to regulate many different cancers; however, its function in thyroid cancer (THCA) remains unexplored. Therefore, we examined the effects of LINC00115 on THCA and the associated molecular mechanisms. In THCA cell lines and tumor samples, the expression levels of LINC00115, miR-489-3p, and EVA1A were analyzed by qRT-PCR along with respective controls. Cell viability, migration, and apoptosis were analyzed by employing CCK-8, transwell, and western blotting assays, respectively. Xenograft experiments were done to assess in vivo tumor growth. The interaction among LINC00115, miR-489-3p, and EVA1A was tested using RNA-binding protein immunoprecipitation and luciferase assays. Key proteins of the Hippo signaling pathway were ascertained by western blotting. The outcomes elucidated that LINC00115 was overexpressed in THCA cell lines and tumor tissues. LIN00115 knockdown reduced in vitro proliferation and migration but facilitated apoptosis in THCA cells and inhibited in vivo tumor growth. The target of LINC00115 was miR-489-3p, which binds to EVA1A in THCA. Functional assays revealed that miR-489-3p inhibition boosted THCA cell proliferation and migration, but hindered apoptosis. However, EVA1A knockdown resulted in the opposite effects via the Hippo signaling pathway. Additionally, miR-489-3p inhibition partially negated the effects of LINC00115 knockdown in THCA cells, and EVA1A knockdown remarkably impeded the effects of miR-489-3p inhibition in THCA cells. Thus, LINC00115 knockdown suppressed THCA carcinogenesis via targeting miR-489-3p, which regulates EVA1A expression and affects the Hippo signaling pathway.

Immunological processes of enhancers and suppressors of long non-coding RNAs associated with brain tumors and inflammation

Immunological processes, such as inflammation, can both cause tumor suppression and cancer progression. Moreover, deregulated levels of long non-coding RNA (lncRNA) expression in the brain may cause inflammation and lead to the growth of tumors. Like other biological processes, the immune system's role in cancer is complicated, varies, and can help or hurt the cancer's maintenance. According to research, inflammation and brain cancer are correlated via several signaling pathways. A variety of lncRNAs have recently been revealed to influence cancer by modulating inflammatory pathways. As a result, lncRNAs have the potential to influence carcinogenesis, tumor formation, or tumor suppression via an increase or decrease in inflammation functions. Although the study and targeting of lncRNAs have made great progress in the treatment of cancer, there are definitely limitations and challenges. Using new technologies like nanocarriers and cell-penetrating peptides (CPPs) to target treatments without hurting healthy body tissues has shown to be very effective. In this review article, we have collected significantly related lncRNAs and their inhibitory or stimulating roles in inflammation and brain cancer for the first time. However, there are limitations, such as side effects and damage to normal tissues. With the advancement of new targeting technologies, these lncRNAs may be candidates for the specific targeting therapy of brain cancers by limiting inflammation or stimulating the immune system against them in the future.

LINC00115 promotes chemoresistant breast cancer stem-like cell stemness and metastasis through SETDB1/PLK3/HIF1α signaling

BACKGROUND

Cancer stem-like cell is a key barrier for therapeutic resistance and metastasis in various cancers, including breast cancer, yet the underlying mechanisms are still elusive. Through a genome-wide lncRNA expression profiling, we identified that LINC00115 is robustly upregulated in chemoresistant breast cancer stem-like cells (BCSCs).

METHODS

LncRNA microarray assay was performed to document abundance changes of lncRNAs in paclitaxel (PTX)-resistant MDA-MB-231 BCSC (ALDH+) and non-BCSC (ALDH-). RNA pull-down and RNA immunoprecipitation (RIP) assays were performed to determine the binding proteins of LINC00115. The clinical significance of the LINC00115 pathway was examined in TNBC metastatic lymph node tissues. The biological function of LINC00115 was investigated through gain- and loss-of-function studies. The molecular mechanism was explored through RNA sequencing, mass spectrometry, and the CRISPR/Cas9-knockout system. The therapeutic potential of LINC00115 was examined through xenograft animal models.

RESULTS

LINC00115 functions as a scaffold lncRNA to link SETDB1 and PLK3, leading to enhanced SETDB1 methylation of PLK3 at both K106 and K200 in drug-resistant BCSC. PLK3 methylation decreases PLK3 phosphorylation of HIF1α and thereby increases HIF1α stability. HIF1α, in turn, upregulates ALKBH5 to reduce m6A modification of LINC00115, resulting in attenuated degradation of YTHDF2-dependent m6A-modified RNA and enhanced LINC00115 stability. Thus, this positive feedback loop provokes BCSC phenotypes and enhances chemoresistance and metastasis in triple-negative breast cancer. SETDB1 inhibitor TTD-IN with LINC00115 ASO sensitizes PTX-resistant cell response to chemotherapy in a xenograft animal model. Correlative expression of LINC00115, methylation PLK3, SETDB1, and HIF1α are prognostic for clinical triple-negative breast cancers.

CONCLUSIONS

Our findings uncover LINC00115 as a critical regulator of BCSC and highlight targeting LINC00115 and SETDB1 as a potential therapeutic strategy for chemotherapeutic resistant breast cancer.

Long intergenic non-protein coding RNA 115 (Linc00115): A notable oncogene in human malignancies

Long noncoding RNAs (LncRNAs) are RNA transcripts ranging from 200 to 1000 nucleotides that have emerged as critical regulators of gene expression. Growing evidence highlights their involvement in tumor development. In particular, long intergenic non-protein coding RNA115 (Linc00115) has been identified as an oncogene across various human malignancies, with aberrant expression strongly linked to poor clinical outcomes in cancer patients. This review aims to delve into the expression patterns of Linc00115 and elucidate the underlying molecular mechanisms behind its oncogenic properties. Moreover, we discuss the potential utility of Linc00115 as a valuable diagnostic and prognostic biomarker in cancer.

LINC00115 promotes gastric cancer partly by the miR-212-5p/ATPAF1 axis

LncRNAs are known to be key regulators in the initiation and development of diverse cancers. Whether LINC00115 is involved in the regulation of gastric cancer (GC) progression remains unclear. Here, we aimed to show the function of LINC00115 in GC. RT-qPCR was used to measure gene expression in GC tissues and cells. Colony formation, EdU, TUNEL, and wound healing assays were used to analyze cellular processes in GC. The in vivo GC xenograft model was established. We observed that LINC00115 was highly expressed in GC. Functionally, silencing LINC00115 inhibited GC cell proliferation, and migration but facilitated GC apoptosis. Mechanistically, LINC00115 sponged miR-212-5p, while miR-212-5p targeted ATPAF1 in GC cells. Rescue assays showed ATPAF1 overexpression countervailed the inhibitory role of LINC00115 depletion in GC progression in vitro and in vivo. Overall, LINC00115 promoted GC progression by upregulating ATPAF1 via miR-212-5p.

LINC01980 induced by TGF-beta promotes hepatocellular carcinoma metastasis via miR-376b-5p/E2F5 axis

Hepatocellular carcinoma (HCC) is one of the most aggressive human malignancies worldwide. However, the molecular mechanism of HCC metastasis is largely unknown. Long non-coding RNA (lncRNA) plays a key role in gene regulation, and dysregulation of lncRNA is critical to cancer metastasis. LINC01980 has been reported in ESCC recently, but the mechanism underlying its function in HCC is still unknown. In this study, we found that LINC01980 was upregulated and associated with notably poor overall survival in HCC patients. Functionally, LINC01980 played a carcinogenic role and promoted HCC metastasis. Mechanically, LINC01980 enhanced the E2F5 expression via competitively binding miR-376b-5p, thereby inducing epithelial-mesenchymal transition and promoting HCC cells migration and invasion. In addition, LINC01980-mediated HCC cells metastasis was dependent on E2F5. What's more, TGF-β activated LINC01980 transcription through the canonical TGF-β/SMAD signaling pathway in HCC. In conclusion, LINC01980, activated by the canonical TGF-β/SMAD pathway, promoted HCC metastasis via miR-376b-5p/E2F5 axis. Therefore, LINC01980 might be a potential prognostic biomarker and therapeutic target of HCC.

Role of Non-Coding RNAs in TGF-β Signalling in Glioma

Brain tumours and Gliomas, in particular, are among the primary causes of cancer mortality worldwide. Glioma diagnosis and therapy have not significantly improved despite decades of efforts. Autocrine TGF-β signalling promotes glioma proliferation, invasion, epithelial-to-mesenchymal transition (EMT), and drug resistance. Non-coding RNAs such as miRNA, lncRNA, and circRNAs have emerged as critical transcriptional and post-transcriptional regulators of TGF-β pathway components in glioma. Here, we summarize the complex regulatory network among regulatory ncRNAs and TGF-β pathway during Glioma pathogenesis and discuss their role as potential therapeutic targets for Gliomas.

METTL3-mediated m6A modification of LINC00839 maintains glioma stem cells and radiation resistance by activating Wnt/β-catenin signaling

Long noncoding RNAs (lncRNAs) are involved in glioma initiation and progression. Glioma stem cells (GSCs) are essential for tumor initiation, maintenance, and therapeutic resistance. However, the biological functions and underlying mechanisms of lncRNAs in GSCs remain poorly understood. Here, we identified that LINC00839 was overexpressed in GSCs. A high level of LINC00839 was associated with GBM progression and radiation resistance. METTL3-mediated m6A modification on LINC00839 enhanced its expression in a YTHDF2-dependent manner. Mechanistically, LINC00839 functioned as a scaffold promoting c-Src-mediated phosphorylation of β-catenin, thereby inducing Wnt/β-catenin activation. Combinational use of celecoxib, an inhibitor of Wnt/β-catenin signaling, greatly sensitized GSCs to radiation. Taken together, our results showed that LINC00839, modified by METTL3-mediated m6A, exerts tumor progression and radiation resistance by activating Wnt/β-catenin signaling.

Regulation of EMT Markers, Extracellular Matrix, and Associated Signalling Pathways by Long Non-Coding RNAs in Glioblastoma Mesenchymal Transition: A Scoping Review

Glioblastoma (GBM) mesenchymal (MES) transition can be regulated by long non-coding RNAs (lncRNAs) via modulation of various factors (Epithelial-to-Mesenchymal (EMT) markers, biological signalling, and the extracellular matrix (ECM)). However, understanding of these mechanisms in terms of lncRNAs is largely sparse. This review systematically analysed the mechanisms by which lncRNAs influence MES transition in GBM from a systematic search of the literature (using PRISMA) performed in five databases (PubMed, MEDLINE, EMBASE, Scopus, and Web of Science). We identified a total of 62 lncRNAs affiliated with GBM MES transition, of which 52 were upregulated and 10 were downregulated in GBM cells, where 55 lncRNAs were identified to regulate classical EMT markers in GBM (E-cadherin, N-cadherin, and vimentin) and 25 lncRNAs were reported to regulate EMT transcription factors (ZEB1, Snai1, Slug, Twist, and Notch); a total of 16 lncRNAs were found to regulate the associated signalling pathways (Wnt/β-catenin, PI3k/Akt/mTOR, TGFβ, and NF-κB) and 14 lncRNAs were reported to regulate ECM components (MMP2/9, fibronectin, CD44, and integrin-β1). A total of 25 lncRNAs were found dysregulated in clinical samples (TCGA vs. GTEx), of which 17 were upregulated and 8 were downregulated. Gene set enrichment analysis predicted the functions of HOXAS3, H19, HOTTIP, MEG3, DGCR5, and XIST at the transcriptional and translational levels based on their interacting target proteins. Our analysis observed that the MES transition is regulated by complex interplays between the signalling pathways and EMT factors. Nevertheless, further empirical studies are required to elucidate the complexity in this process between these EMT factors and the signalling involved in the GBM MES transition.

Zinc Finger E-Box Binding Homeobox Family: Non-Coding RNA and Epigenetic Regulation in Gliomas

Gliomas are the most common malignant brain tumours. Among them, glioblastoma (GBM) is a grade four tumour with a median survival of approximately 15 months and still limited treatment options. Although a classical epithelial to mesenchymal transition (EMT) is not the case in glioma due to its non-epithelial origin, the EMT-like processes may contribute largely to the aggressive and highly infiltrative nature of these tumours, thus promoting invasive phenotype and intracranial metastasis. To date, many well-known EMT transcription factors (EMT-TFs) have been described with clear, biological functions in glioma progression. Among them, EMT-related families of molecules such as SNAI, TWIST and ZEB are widely cited, well-established oncogenes considering both epithelial and non-epithelial tumours. In this review, we aimed to summarise the current knowledge with a regard to functional experiments considering the impact of miRNA and lncRNA as well as other epigenetic modifications, with a main focus on ZEB1 and ZEB2 in gliomas. Although we explored various molecular interactions and pathophysiological processes, such as cancer stem cell phenotype, hypoxia-induced EMT, tumour microenvironment and TMZ-resistant tumour cells, there is still a pressing need to elucidate the molecular mechanisms by which EMT-TFs are regulated in gliomas, which will enable researchers to uncover novel therapeutic targets as well as improve patients' diagnosis and prognostication.

Epigenetic programing of cancer stemness by transcription factors-non-coding RNAs interactions

Cancer 'stemness' is fundamental to cancer existence. It defines the ability of cancer cells to indefinitely perpetuate as well as differentiate. Cancer stem cell populations within a growing tumor also help evade the inhibitory effects of chemo- as well as radiation-therapies, in addition to playing an important role in cancer metastases. NF-κB and STAT-3 are representative transcription factors (TFs) that have long been associated with cancer stemness, thus presenting as attractive targets for cancer therapy. The growing interest in non-coding RNAs (ncRNAs) in the recent years has provided further insight into the mechanisms by which TFs influence cancer stem cell characteristics. There is evidence for a direct regulation of TFs by ncRNAs, such as, microRNAs (miRNAs), long non-coding RNAs (lncRNAs) as well as circular RNAs (circRNAs), and vice versa. Additionally, the TF-ncRNAs regulations are often indirect, involving ncRNA-target genes or the sponging of other ncRNA species by individual ncRNAs. The information is rapidly evolving and this review provides a comprehensive review of TF-ncRNAs interactions with implications on cancer stemness and in response to therapies. Such knowledge will help uncover the many levels of tight regulations that control cancer stemness, providing novel opportunities and targets for therapy in the process.

Tumor stemness score to estimate epithelial-to-mesenchymal transition (EMT) and cancer stem cells (CSCs) characterization and to predict the prognosis and immunotherapy response in bladder urothelial carcinoma

BACKGROUND

A growing number of investigations have suggested a close link between cancer stem cells (CSCs), epithelial-to-mesenchymal transition (EMT), and the tumor microenvironment (TME). However, the relationships between these physiological processes in bladder urothelial carcinoma (BLCA) remain unclear.

METHODS

We first explored biomarkers of tumor stemness (TS) by single-cell sequencing analysis. Then, subtypes of bladder urothelial carcinoma (BLCA) were identified using clustering analysis based on TS biomarkers. The TS score was constructed using principal component analysis to quantify tumor stemness in BLCA. Then, meta-analysis was performed to measure the hazard ratio of the TS score in BLCA cohorts. Moreover, we evaluated the clinical value of the TS score for predicting the response to tumor immunotherapy using immunotherapy cohorts. Finally, we built an EMT cell model by treating T24 cells with TGF-β and validated the relationship between the TS score and the EMT process in tumors by real-time quantitative PCR, cell invasion assays, and RNA-seq. In total, 3846 BLCA cells, 6 cell lines, 1627 BLCA samples, and 9858 samples from 32 other types of tumors were included in our study.

RESULTS

Three TS clusters and two TS-related gene clusters were identified with differential EMT activity status, CSC features, and TME characteristics in BLCA. Then, a TS scoring system was established with 61 TS-related genes to quantify the TS. The prognostic value of the TS score was then confirmed in multiple independent cohorts. A high TS score was associated with high EMT activity, CSC characteristics, high stromal cell content, high TP53 mutation rate, poor prognosis, and high tumor immunotherapy tolerance. The cell line experiment and RNA-seq further validated that our TS score can reflect the EMT and CSC characterization of tumor cells.

CONCLUSION

Overall, this research provides a better understanding of tumor invasion and metastasis mechanisms through an analysis of TS patterns with different EMT processes and CSC characteristics. The TS score provides an index for EMT and CSC research and helps clinicians develop treatment plans and predict outcomes for patients.

LINC01711 promotes transforming growth factor-beta (TGF-β) induced invasion in glioblastoma multiforme (GBM) by acting as a competing endogenous RNA for miR-34a and promoting ZEB1 expression

GBM is the central nervous system's most aggressive and malignant tumor. TGF-β expression is elevated in GBM, and it promotes invasion and EMT. TGF-β regulates the expression of several lncRNAs, which promote glioma pathogenesis. Here we characterize the role of TGF-β-induced lncRNA- LINC01711 in glioma pathogenesis. We show that LINC01711 expression is significantly upregulated in GBM tissues and is associated with poor overall survival of GBM patients. Loss-of-function studies illustrate that LINC01711 promotes proliferation, migration, and invasion in GBM. In addition, LINC01711 depletion sensitizes glioma cells to Temozolomide (TMZ) induced apoptosis by inhibiting ZEB1 expression. LINC01711 functions as a competing endogenous RNA for miR-34a and promotes ZEB1 expression to regulate invasion. Our findings suggest that LINC01711 is an attractive therapeutic target for GBM.

Non-coding RNAs and glioma: Focus on cancer stem cells

Glioblastoma and gliomas can have a wide range of histopathologic subtypes. These heterogeneous histologic phenotypes originate from tumor cells with the distinct functions of tumorigenesis and self-renewal, called glioma stem cells (GSCs). GSCs are characterized based on multi-layered epigenetic mechanisms, which control the expression of many genes. This epigenetic regulatory mechanism is often based on functional non-coding RNAs (ncRNAs). ncRNAs have become increasingly important in the pathogenesis of human cancer and work as oncogenes or tumor suppressors to regulate carcinogenesis and progression. These RNAs by being involved in chromatin remodeling and modification, transcriptional regulation, and alternative splicing of pre-mRNA, as well as mRNA stability and protein translation, play a key role in tumor development and progression. Numerous studies have been performed to try to understand the dysregulation pattern of these ncRNAs in tumors and cancer stem cells (CSCs), which show robust differentiation and self-regeneration capacity. This review provides recent findings on the role of ncRNAs in glioma development and progression, particularly their effects on CSCs, thus accelerating the clinical implementation of ncRNAs as promising tumor biomarkers and therapeutic targets.

STAT3 Inhibitors: A Novel Insight for Anticancer Therapy of Pancreatic Cancer

The signal transducer and activator of transcription (STAT) is a family of intracellular cytoplasmic transcription factors involved in many biological functions in mammalian signal transduction. Among them, STAT3 is involved in cell proliferation, differentiation, apoptosis, and inflammatory responses. Despite the advances in the treatment of pancreatic cancer in the past decade, the prognosis for patients with pancreatic cancer remains poor. STAT3 has been shown to play a pro-cancer role in a variety of cancers, and inhibitors of STAT3 are used in pre-clinical and clinical studies. We reviewed the relationship between STAT3 and pancreatic cancer and the latest results on the use of STAT3 inhibitors in pancreatic cancer, with the aim of providing insights and ideas around STAT3 inhibitors for a new generation of chemotherapeutic modalities for pancreatic cancer.

Non-coding RNAs and epithelial mesenchymal transition in cancer: molecular mechanisms and clinical implications

Epithelial-mesenchymal transition (EMT) is a fundamental process for embryonic development during which epithelial cells acquire mesenchymal characteristics, and the underlying mechanisms confer malignant features to carcinoma cells such as dissemination throughout the organism and resistance to anticancer treatments. During the past decades, an entire class of molecules, called non-coding RNA (ncRNA), has been characterized as a key regulator of almost every cellular process, including EMT. Like protein-coding genes, ncRNAs can be deregulated in cancer, acting as oncogenes or tumor suppressors. The various forms of ncRNAs, including microRNAs, PIWI-interacting RNAs, small nucleolar RNAs, transfer RNA-derived RNA fragments, long non-coding RNAs, and circular RNAs can orchestrate the complex regulatory networks of EMT at multiple levels. Understanding the molecular mechanism underlying ncRNAs in EMT can provide fundamental insights into cancer metastasis and may lead to novel therapeutic approaches. In this review, we describe recent advances in the understanding of ncRNAs in EMT and provide an overview of recent ncRNA applications in the clinic.

The Role of Non-Coding RNAs in Glioma

For decades, research in cancer biology has been focused on the protein-coding fraction of the human genome. However, with the discovery of non-coding RNAs (ncRNAs), it has become known that these entities not only function in numerous fundamental life processes such as growth, differentiation, and development, but also play critical roles in a wide spectrum of human diseases, including cancer. Dysregulated ncRNA expression is found to affect cancer initiation, progression, and therapy resistance, through transcriptional, post-transcriptional, or epigenetic processes in the cell. In this review, we focus on the recent development and advances in ncRNA biology that are pertinent to their role in glioma tumorigenesis and therapy response. Gliomas are common, and are the most aggressive type of primary tumors, which account for ~30% of central nervous system (CNS) tumors. Of these, glioblastoma (GBM), which are grade IV tumors, are the most lethal brain tumors. Only 5% of GBM patients survive beyond five years upon diagnosis. Hence, a deeper understanding of the cellular non-coding transcriptome might help identify biomarkers and therapeutic agents for a better treatment of glioma. Here, we delve into the functional roles of microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA) in glioma tumorigenesis, discuss the function of their extracellular counterparts, and highlight their potential as biomarkers and therapeutic agents in glioma.

Oncofetal proteins and cancer stem cells

Cancer stem cells (CSCs) are considered as a small population of cells with stem-like properties within the tumor bulk, and are largely responsible for tumor recurrence, metastasis, and therapy resistance. CSCs share critical features with embryonic stem cells (ESCs). The pluripotent transcription factors (TFs) and developmental signaling pathways of ESCs are invariably hijacked by CSCs termed ‘oncofetal drivers’ in many cancers, which are rarely detectable in adult tissues. The unique expression pattern makes oncofetal proteins ideal therapeutic targets in cancer treatment. Therefore, elucidation of oncofetal drivers in cancers is critical for the development of effective CSCs-directed therapy. In this review, we summarize the common pluripotent TFs such as OCT4, SOX2, NANOG, KLF4, MYC, SALL4, and FOXM1, as well as the development signaling including Wnt/β-catenin, Hedgehog (Hh), Hippo, Notch, and TGF-β pathways of ESCs and CSCs. We also describe the newly identified oncofetal proteins that drive the self-renewal, plasticity, and therapy-resistance of CSCs. Finally, we explore how the clinical implementation of targeting oncofetal drivers, including small-molecule inhibitors, vaccines, antibodies, and CAR-T (chimeric antigen receptor T cell) can facilitate the development of CSCs-directed therapy.

LncRNA-Dependent Mechanisms of Transforming Growth Factor-β: From Tissue Fibrosis to Cancer Progression

Transforming growth factor-β (TGF-β) is a crucial pathogenic mediator of inflammatory diseases. In tissue fibrosis, TGF-β regulates the pathogenic activity of infiltrated immunocytes and promotes extracellular matrix production via de novo myofibroblast generation and kidney cell activation. In cancer, TGF-β promotes cancer invasion and metastasis by enhancing the stemness and epithelial mesenchymal transition of cancer cells. However, TGF-β is highly pleiotropic in both tissue fibrosis and cancers, and thus, direct targeting of TGF-β may also block its protective anti-inflammatory and tumor-suppressive effects, resulting in undesirable outcomes. Increasing evidence suggests the involvement of long non-coding RNAs (lncRNAs) in TGF-β-driven tissue fibrosis and cancer progression with a high cell-type and disease specificity, serving as an ideal target for therapeutic development. In this review, the mechanism and translational potential of TGF-β-associated lncRNAs in tissue fibrosis and cancer will be discussed.

lncRNA PRADX is a Mesenchymal Glioblastoma Biomarker for Cellular Metabolism Targeted Therapy

Glioblastoma (GBM) is the most common and lethal type of primary malignant central nervous system (CNS) tumor with an extremely poor prognosis, and the mesenchymal subtype of GBM has the worst prognosis. Here, we found that lncRNA PRADX was overexpressed in the mesenchymal GBM and was transcriptionally regulated by RUNX1-CBFβ complex, overexpressed PRADX suppressed BLCAP expression via interacting with EZH2 and catalyzing trimethylation of lysine 27 on histone H3 (H3K27me3). Moreover, we showed that BLCAP interacted with STAT3 and reduced STAT3 phosphorylation, overexpressed PRADX activated STAT3 phosphorylation, and promoted ACSL1 expression via suppressing BLCAP expression, accelerating tumor metabolism. Finally, we determined that combined of ACSL1 and CPT1 inhibitors could reverse the accelerated cellular metabolism and tumor growth induced by PRADX overexpression in vivo and in vitro. Collectively, PRADX/PRC2 complex activated the STAT3 pathway and energy metabolism in relation to mesenchymal GBM progression. Furthermore, our findings provided a novel therapeutic strategy targeting the energy metabolism activity of GBM.

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.

The Emerging role of EMT-related lncRNAs in therapy resistance and their application as biomarkers

Cancer is the world's second largest cause of death. The most common cancer treatments are surgery, radiation therapy, and chemotherapy. Drug resistance, epithelial-to-mesenchymal transition (EMT), and metastasis are all pressing issues in cancer therapy today. Increasing evidence showed that drug-resistant and EMT are co-related with each other. Indeed, drug-resistant cancer cells possess enhanced EMT and invasive ability. Recent researches have demonstrated lncRNAs (long noncoding RNAs) are noncoding transcripts, which play an important role in the regulation of EMT, metastasis, and drug resistance in different cancers. However, the relationships among lncRNAs, EMT, and drug resistance are still unclear. These effects could be exerted via several signaling pathways such as TGF-β, PI3K-AKT, and Wnt/β-catenin. Identifying the crucial regulatory roles of lncRNAs in these pathways and processes leads to the development of novel targeted therapies. We review the key aspects of lncRNAs associated with EMT and therapy resistance. We focus on the crosstalk between lncRNAs and molecular signaling pathways affecting EMT and drug resistance. Moreover, each of the mentioned lncRNAs could be used as a potential diagnostic, prognostic, and therapeutic biomarker for cancer. Although, there are still many challenges to investigate lncRNAs for clinical applications.

Integrated Analysis of Competitive Endogenous RNA Networks in Acute Ischemic Stroke

Background: Acute ischemic stroke (AIS) is a severe neurological disease with complex pathophysiology, resulting in the disability and death. The goal of this study is to explore the underlying molecular mechanisms of AIS and search for new potential biomarkers and therapeutic targets.

Methods: Integrative analysis of mRNA and miRNA profiles downloaded from Gene Expression Omnibus (GEO) was performed. We explored differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMirs) after AIS. Target mRNAs of DEMirs and target miRNAs of DEGs were predicted with target prediction tools, and the intersections between DEGs and target genes were determined. Subsequently, Gene Ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analyses, Gene set enrichment analysis (GSEA), Gene set variation analysis (GSVA), competitive endogenous RNA (ceRNA) (lncRNA-miRNA-mRNA) network, protein–protein interaction (PPI) network, and gene transcription factors (TFs) network analyses were performed to identify hub genes and associated pathways. Furthermore, we obtained AIS samples with evaluation of immune cell infiltration and used CIBERSORT to determine the relationship between the expression of hub genes and infiltrating immune cells. Finally, we used the Genomics of Drug Sensitivity in Cancer (GDSC) database to predict the effect of the identified targets on drug sensitivity.

Result: We identified 293 DEGs and 26 DEMirs associated with AIS. DEGs were found to be mainly enriched in inflammation and immune-related signaling pathways through enrichment analysis. The ceRNA network included nine lncRNAs, 13 miRNAs, and 21 mRNAs. We used the criterion AUC >0.8, to screen a 3-gene signature (FBL, RPS3, and RPS15) and the aberrantly expressed miRNAs (hsa-miR-125a-5p, hsa-miR-125b-5p, hsa-miR-148b-3p, and hsa-miR-143-3p) in AIS, which were verified by a method of quantitative PCR (qPCR) in HT22 cells. T cells CD8, B cells naïve, and activated NK cells had statistical increased in number compared with the acute cerebral infarction group. By predicting the IC50 of the patient to the drug, AZD0530, Z.LLNle.CHO and NSC-87877 with significant differences between the groups were screened out. AIS demonstrated heterogeneity in immune infiltrates that correlated with the occurrence and development of diseases.

Conclusion: These findings may contribute to a better understanding of the molecular mechanisms of AIS and provide the basis for the development of novel treatment targets in AIS.

In Silico Analysis Identifies Upregulated lncRNA DLGAP1-AS1 Which Is Correlated to Poor Prognosis and Promotes Cell Proliferation in Glioblastoma

Long noncoding RNAs have been reported to regulate the tumorigenesis, growth, and metastasis of glioblastomas. In this study, we identified 1623 differently expressed mRNAs and 38 lncRNAs utilizing the CGGA and TCGA databases. Among these mRNAs and lncRNAs, we focused on DLGAP1-AS1 in this study. The results demonstrated that DLGAP1-AS1 was higher in WHO IV glioma than in WHO II and WHO III gliomas, higher in WHO III glioma than in WHO II glioma samples, higher in IDH1 wildtype glioma than in IDH1-mutant glioma samples, and higher in 1p/19q noncodeletion glioma than in 1p/19q codeletion glioma samples. Moreover, we observed that higher expression levels of DLGAP1-AS1 were correlated to shorter OS time in both low-grade and high-grade gliomas. Next, we evaluated the function of DLGAP1-AS1 in GBM using in vivo experiments. The data revealed that DLGAP1-AS1 knockdown greatly hindered U87 cell and U251 cell proliferation. Using coexpression network analysis, we identified that ATG4A was a potential downstream target of DLGAP1-AS1. The further analysis showed that ATG4B was significantly upregulated and correlated to shorter OS time in gliomas using both the CGGA and TCGA databases. Finally, we showed that ablated ATG4B greatly hindered GBM cell proliferation. Our conclusion suggested that DLGAP1-AS1 may be a potential prognosis biomarker and facilitated the occurrence and development of glioma via ATG4A in GBM.

The long and short non-coding RNAs modulating EZH2 signaling in cancer

Non-coding RNAs (ncRNAs) are a large family of RNA molecules with no capability in encoding proteins. However, they participate in developmental and biological processes and their abnormal expression affects cancer progression. These RNA molecules can function as upstream mediators of different signaling pathways and enhancer of zeste homolog 2 (EZH2) is among them. Briefly, EZH2 belongs to PRCs family and can exert functional roles in cells due to its methyltransferase activity. EZH2 affects gene expression via inducing H3K27me3. In the present review, our aim is to provide a mechanistic discussion of ncRNAs role in regulating EZH2 expression in different cancers. MiRNAs can dually induce/inhibit EZH2 in cancer cells to affect downstream targets such as Wnt, STAT3 and EMT. Furthermore, miRNAs can regulate therapy response of cancer cells via affecting EZH2 signaling. It is noteworthy that EZH2 can reduce miRNA expression by binding to promoter and exerting its methyltransferase activity. Small-interfering RNA (siRNA) and short-hairpin RNA (shRNA) are synthetic, short ncRNAs capable of reducing EZH2 expression and suppressing cancer progression. LncRNAs mainly regulate EZH2 expression via targeting miRNAs. Furthermore, lncRNAs induce EZH2 by modulating miRNA expression. Circular RNAs (CircRNAs), like lncRNAs, affect EZH2 expression via targeting miRNAs. These areas are discussed in the present review with a focus on molecular pathways leading to clinical translation.

Transforming Growth Factor-Beta-Regulated LncRNA-MUF Promotes Invasion by Modulating the miR-34a Snail1 Axis in Glioblastoma Multiforme

Transforming growth factor beta (TGF-β)-regulated long-non-coding RNAs (lncRNAs) modulate several aspects of tumor development such as proliferation, invasion, metastasis, epithelial to mesenchymal transition (EMT), and drug resistance in various cancers, including Glioblastoma multiforme (GBM). We identified several novel differentially expressed lncRNAs upon TGF-β treatment in glioma cells using genome-wide microarray screening. We show that TGF-β induces lncRNA-MUF in glioma cells, and its expression is significantly upregulated in glioma tissues and is associated with poor overall survival of GBM patients. Knockdown of lncRNA-MUF reduces proliferation, migration, and invasion in glioma cells and sensitizes them to temozolomide (TMZ)-induced apoptosis. In addition, lncRNA-MUF downregulation impairs TGF-β-induced smad2/3 phosphorylation. In line with its role in regulating invasion, lncRNA-MUF functions as a competing endogenous RNA (ceRNA) for miR-34a and promotes Snail1 expression. Collectively, our findings suggest lncRNA-MUF as an attractive therapeutic target for GBM.

Small nucleolar RNA SNORA71A promotes epithelial-mesenchymal transition by maintaining ROCK2 mRNA stability in breast cancer

Metastasis is the primary reason of death in patients with cancer. Small nucleolar noncoding RNAs (snoRNAs) are conserved 60–300 nucleotide noncoding RNAs, involved in post‐transcriptional regulation of mRNAs and noncoding RNAs. Despite their essential roles in cancer, the roles of snoRNAs in epithelial‐mesenchymal transition (EMT)‐induced metastasis have not been studied extensively. Here, we used small RNA sequencing to screen for snoRNAs related to EMT and breast cancer metastasis. We found a higher expression of SNORA71A in metastatic breast cancer tissues compared to nonmetastatic samples. Additionally, SNORA71A promoted the proliferation, migration, invasion and EMT of MCF‐7 and MDA‐MB‐231 cells. Mechanistically, SNORA71A elevated mRNA and protein levels of ROCK2, a negative regulator of TGF‐β signaling. Rescue assays showed ROCK2 abrogated the SNORA71A‐mediated increase in proliferation, migration, invasion and EMT. Binding of SNORA71A to mRNA stability regulatory protein G3BP1, increased ROCK2 mRNA half‐life. Furthermore, G3BP1 depletion abolished the SNORA71A‐mediated upregulation of ROCK2. In vivo, SNORA71A overexpression promoted breast tumor growth, and SNORA71A knockdown inhibited breast cancer growth and metastasis. We suggest SNORA71A enhances metastasis of breast cancer by binding to G3BP1 and stabilizing ROCK2.

Identification of an IL-4-Related Gene Risk Signature for Malignancy, Prognosis and Immune Phenotype Prediction in Glioma

Background: Emerging molecular and genetic biomarkers have been introduced to classify gliomas in the past decades. Here, we introduced a risk signature based on the cellular response to the IL-4 gene set through Least Absolute Shrinkage and Selection Operator (LASSO) regression analysis. Methods: In this study, we provide a bioinformatic profiling of our risk signature for the malignancy, prognosis and immune phenotype of glioma. A cohort of 325 patients with whole genome RNA-seq expression data from the Chinese Glioma Genome Atlas (CGGA) dataset was used as the training set, while another cohort of 667 patients from The Cancer Genome Atlas (TCGA) dataset was used as the validating set. The LASSO model identified a 10-gene signature which was considered as the optimal model. Results: The signature was confirmed to be a good predictor of clinical and molecular features involved in the malignancy of gliomas. We also identified that our risk signature could serve as an independently prognostic biomarker in patients with gliomas (p < 0.0001). Correlation analysis showed that our risk signature was strongly correlated with the Tregs, M0 macrophages and NK cells infiltrated in the microenvironment of glioma, which might be a supplement to the existing incomplete innate immune mechanism of glioma phenotypes. Conclusions: Our IL-4-related gene signature was associated with more aggressive and immunosuppressive phenotypes of gliomas. The risk score could predict prognosis independently in glioma, which might provide a new insight for understanding the IL-4 involved mechanism of gliomas.

LncRNA LINC00115 facilitates lung cancer progression through miR-607/ITGB1 pathway

Dysregulated long noncoding RNAs (lncRNAs) have potential roles in various cancer types. The objective of this study was to investigate the expression and the underlying role of long intergenic nonprotein coding RNA 115 (LINC00115) in lung cancer. The relative expression of LINC00115 and miR-607 in tumor tissues and cells was detected by real-time PCR. After overexpression or knockdown of LINC00115 expression in tumor cells, the changes in the proliferation, migration, and invasion capacities were detected via Counting Kit-8 (CCK-8) assay and transwell assays. The interplay among LINC00115, miR-607, and integrin β1 (ITGB1) was confirmed by bioinformatics analyses and luciferase reporter assay. In addition, tumor cells with LINC00115 knockdown were injected into nude mice to investigate the effect of LINC00115 on tumorigenesis in vivo. LINC00115 was highly expressed in tumor tissues and cells. LINC00115 promoted the malignant properties of tumor cells. Investigation to its molecular mechanism revealed that LINC00115 functioned as a competitive endogenous RNA (ceRNA), regulating the expression of ITGB1 by sponging miR-607 to affect tumor growth. The LINC00115/miR-607/ITGB1 signaling axis might be a novel therapeutic target in lung cancer.

Association study of a genetic variant in the long intergenic noncoding RNA (linc01080) with schizophrenia in Han Chinese

BACKGROUND

Schizophrenia is currently considered to be a polygene-related disease with unknown etiology. This research will verify whether the single nucleotide polymorphism (SNP) of the long intergenic noncoding RNA01080 (linc01080) contributes to the susceptibility and phenotypic heterogeneity of schizophrenia, with a view to providing data support for the prevention and individualized treatment of this disease.

METHOD

The SNP rs7990916 in linc01080 were genotyped in 1139 schizophrenic and 1039 controls in a Southern Chinese Han population by the improved multiplex ligation detection reaction (imLDR) technique. Meanwhile, we assessed and analyzed the association between this SNP and schizophrenics' clinical symptoms, and the cognitive function.

RESULT

There was no significant difference in genotype distribution, allele frequency distribution, gender stratification analysis between the two groups. However, the SNP of rs7990916 was significantly associated with the age of onset in patients with schizophrenia (P = 8.22E-07), patients with T allele had earlier onset age compared with CC genotype carriers. In terms of cognitive function, patients with T allele scored lower than CC genotype carriers in the Tower of London score and symbol coding score in the Brief assessment of Cognition (BACS), and the difference was statistically significant (P = 0.014, P = 0.022, respectively).

CONCLUSION

Our data show for the first time that linc01080 polymorphism may affect the age of onset and neurocognitive function in patients with schizophrenia.

N6-Methyladenosine-Related Long Non-coding RNA Signature Associated With Prognosis and Immunotherapeutic Efficacy of Clear-Cell Renal Cell Carcinoma

Increasing evidence suggests that N6-methyladenosine (m6A) and long non-coding RNAs (lncRNAs) play important roles in cancer progression and immunotherapeutic efficacy in clear-cell renal cell carcinoma (ccRCC). In this study, we conducted a comprehensive ccRCC RNA-seq analysis using The Cancer Genome Atlas data to establish an m6A-related lncRNA prognostic signature (m6A-RLPS) for ccRCC. Forty-four prognostic m6A-related lncRNAs (m6A-RLs) were screened using Pearson correlation analysis (|R| > 0.7, p < 0.001) and univariable Cox regression analysis (p < 0.01). Using consensus clustering, the patients were divided into two clusters with different overall survival (OS) rates and immune status according to the differential expression of the lncRNAs. Gene set enrichment analysis corroborated that the clusters were enriched in immune-related activities. Twelve prognostic m6A-RLs were selected and used to construct the m6A-RLPS through least absolute shrinkage and selection operator Cox regression. We validated the differential expression of the 12 lncRNAs between tumor and non-cancerous samples, and the expression levels of four m6A-RLs were further validated using Gene Expression Omnibus data and Lnc2Cancer 3.0 database. The m6A-RLPS was verified to be an independent and robust predictor of ccRCC prognosis using univariable and multivariable Cox regression analyses. A nomogram based on age, tumor grade, clinical stage, and m6A-RLPS was generated and showed high accuracy and reliability at predicting the OS of patients with ccRCC. The prognostic signature was found to be strongly correlated to tumor-infiltrating immune cells and immune checkpoint expression. In conclusion, we established a novel m6A-RLPS with a favorable prognostic value for patients with ccRCC. The 12 m6A-RLs included in the signature may provide new insights into the tumorigenesis and allow the prediction of the treatment response of ccRCC.

Down-regulated LINC00115 inhibits prostate cancer cell proliferation and invasion via targeting miR-212-5p/FZD5/Wnt/β-catenin axis

Prostate cancer is the second most frequent malignancy in men worldwide, and its incidence is increasing. Therefore, it is urgently required to clarify the underlying mechanisms of prostate cancer. Although the long non‐coding RNA LINC00115 was identified as an oncogene in several cancers, the expression and function of LINC00115 in prostate cancer have not been explored. Our results showed that LINC00115 was significantly up‐regulated in prostate cancer tissues, which was significantly associated with a poor prognosis for prostate cancer patients. Functional studies showed that knockdown LINC00115 inhibited cell proliferation and invasion. In addition, LINC00115 served as a competing endogenous RNA (ceRNA) through sponging miR‐212‐5p to release Frizzled Family Receptor 5 (FZD5) expression. The expression of miR‐212‐5p was noticeably low in tumour tissues, and FZD5 expression level was down‐regulated with the knockdown of LINC00115. Knockdown LINC00115 inhibited the Wnt/β‑catenin signalling pathway by inhibiting the expression of FZD5. Rescue experiments further showed that LINC00115 inhibits prostate cancer cell proliferation and invasion via targeting miR‐212‐5p/ FZD5/ Wnt/β‐catenin axis. The present study provided clues that LINC00115 may be a promising novel therapeutic target for prostate cancer patients.

Network Pharmacology Analysis of Molecular Mechanism of Curcuma Longa L. extracts Regulating Glioma Immune Inflammatory Factors: Implications for Precise Cancer Treatment

INTRODUCTION

Curcuma longa L. has been associated with different antioxidant, anti-inflammatory, bactericidal and anticancer effects, but the mechanisms of the effects are not yet clearly understood. This study aimed to investigate the key targets and the effect of potential molecular mechanisms of Curcuma longa L. extracts on glioma using different network pharmacology analysis approaches.

METHODS

The components of Curcuma longa were extracted by gas chromatography-mass spectrometry (GC-MS), and the active components related to the occurrence and development of glioma were determined by traditional Chinese medicine systems pharmacology database and analysis platform (TCMSP) database, and the same targets of the active components and glioma were screened by network pharmacology approach. Then, the protein's function and regulatory pathway of the common targets were analyzed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. The protein's action and regulatory pathway of the common targets were analyzed with the Cytoscape package using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database to construct the target interaction network through which the key targets were identified.

RESULTS

GC-MS combined with TCMSP database was used to identify the active components related to the occurrence and development of glioma in Curcuma longa. Finally, we identified the active components 1-(1,5-Dimethyl-4-hexenyl)-4-methyl benzene and Zingiberene. At the same time, 190 target genes of Curcuma longa extracts on glioma were obtained using the Venn diagram. The results of GO analysis showed that the biological processes involved included a response to stimulation, metabolic process, inflammatory process, cell differentiation, and regulation of biological processes. KEGG analysis showed that the PI3K-Akt signaling pathway, MAPK signaling pathway, Th17 cell differentiation, and proteoglycan pathway might be involved in cancer. Further analyses showed that the IL-17 signaling pathway and Interleukin-4 and interleukin-13 signaling were involved in the inflammatory pathway. The analysis of key nodes showed that GSK3B, MAPK14, HSP90AA1, MAPK3 and MAPK8 were IL-17 signaling pathways, while HIF1A and JAK3 were Interleukin-4 and interleukin-13 signaling pathways.

CONCLUSION

Curcuma longa extracts can regulate the occurrence and development of glioma by regulating the immune-inflammatory responses.

Noncoding RNAs involved in the STAT3 pathway in glioma

Glioma is the most common malignant primary brain tumour in adults. Despite improvements in neurosurgery and radiotherapy, the prognosis of glioma patients remains poor. One of the main limitations is that there are no proper clinical therapeutic targets for glioma. Therefore, it is crucial to find one or more effective targets. Signal transducer and activator of transcription 3 (STAT3) is a member of the STAT family of genes. Abnormal expression of STAT3 is involved in the process of cell proliferation, migration, invasion, immunosuppression, angiogenesis, dryness maintenance, and resistance to radiotherapy and chemotherapy in glioma. Therefore, STAT3 has been considered an ideal therapeutic target in glioma. Noncoding RNAs (ncRNAs) are a group of genes with limited or no protein-coding capacity that can regulate gene expression at the epigenetic, transcriptional and posttranscriptional level. In this review, we summarized the ncRNAs that are correlated with the ectopic expression of STAT3 in glioma.

TGF-β1-mediated exosomal lnc-MMP2-2 increases blood-brain barrier permeability via the miRNA-1207-5p/EPB41L5 axis to promote non-small cell lung cancer brain metastasis

Brain metastases remain a major problem in patients with advanced non-small cell lung cancer (NSCLC). The permeability of the blood-brain barrier (BBB) is highly increased during lung cancer brain metastasis; however, the underlying mechanism remains largely unknown. We previously found that lnc-MMP2-2 is highly enriched in tumor growth factor (TGF)-β1-mediated exosomes and regulates the migration of lung cancer cells. This study aimed to explore the role of exosomal lnc-MMP2-2 in the regulation of BBB and NSCLC brain metastasis. Here, using endothelial monolayers and mouse models, we found that TGF-β1-mediated NSCLC-derived exosomes efficiently destroyed tight junctions and the integrity of these natural barriers. Overexpression of lnc-MMP2-2 in human brain microvascular endothelial cells increased vascular permeability in endothelial monolayers, whereas inhibition of lnc-MMP2-2 alleviated these effects. Furthermore, lnc-MMP2-2 knockdown markedly reduced NSCLC brain metastasis in vivo. Mechanistically, through luciferase reporter assays, RNA pull-down assay, and Ago2 RNA immunoprecipitation assay, we showed that lnc-MMP2-2 served as a microRNA sponge or a competing endogenous RNA for miR-1207-5p and consequently modulated the derepression of EPB41L5. In conclusion, TGF-β1-mediated exosomal lnc-MMP2-2 increases BBB permeability to promote NSCLC brain metastasis. Thus, exosomal lnc-MMP2-2 may be a potential biomarker and therapeutic target against lung cancer brain 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.

A Positive Feedback Loop of Long Noncoding RNA LINC00152 and KLF5 Facilitates Breast Cancer Growth

The long noncoding RNA (lncRNA) LINC00152, also known as CYTOR, displays aberrant expression in various cancers. However, its clinical value and functional mechanisms in breast cancer remain insufficiently understood. Our study found that LINC00152 is significantly upregulated in breast cancer, and that it acts as an indicator of poor survival prognosis. Further studies revealed that LINC00152 knockdown suppresses cell proliferation and tumorigenicity in vitro and in vivo. Mechanistic analyses demonstrated that LINC00152 directly binds to KLF5 protein and increases KLF5 stability. Moreover, LINC00152 is also a KLF5-responsive lncRNA, and KLF5 activates LINC00152 transcription by directly binding to its promoter. Our study suggests that LINC00152 promotes tumor progression by interacting with KLF5. LINC00152 may be a valuable prognostic predictor for breast cancer, and the positive feedback loop of LINC00152-KLF5 could be a therapeutic target in pharmacological strategies.

Synthesis and evaluation of the epithelial-to- mesenchymal inhibitory activity of indazole-derived imidazoles as dual ALK5/p38α MAP inhibitors

Drugs of targeting both activin receptor-like kinase 5 (ALK5) and p38α have therapeutic advantages, making them attractive treatment options for tumors. Two series of 4-(1H-indazol-5-yl)-5-(6-methylpyridin-2-yl)-1H-imidazoles 13a-g and 4-(1-methyl-1H-indazol-5-yl)-5-(6-methylpyridin-2-yl)-1H-imidazoles 20a-g were synthesized and evaluated for ALK5 and p38α mitogen-activated protein kinase inhibitory activity. The most potent compound, 13c (J-1090), inhibited ALK5- and p38α-mediated phosphorylation with half-maximal inhibitor concentrations of 0.004 μM and 0.004 μM, respectively, in the enzymatic assay. In this study, the effectiveness of 13c in transforming growth factor (TGF-β)-exposed U87MG cells was investigated using western blotting, immunofluorescence assays, cell migration assay, invasion assay, and RT-PCR analysis. 13c inhibited the protein expression of Slug and the protein and RNA expression of the mesenchymal-related proteins N-cadherin and vimentin. Furthermore, 13c markedly suppressed TGF-β-induced epithelial-to-mesenchymal transition (EMT), migration, and invasion in U87MG cells. These results suggest that 13c is a novel inhibitor of ALK5 with potential utility in the treatment of human glioma.

The role of cigarette smoke-induced pulmonary vascular endothelial cell apoptosis in COPD

Chronic obstructive pulmonary disease (COPD) is one of the most common chronic respiratory diseases with high morbidity and mortality. It has become the fifth most burdened and the third most deadly disease in the global economy and increases year by year. The prevention and treatment of COPD are urgent. Smoking is the main and most common risk factor for COPD. Cigarette smoke (CS) contains a large number of toxic substances, can cause a series of changes in the trachea, lung tissue, pulmonary blood vessels, and promotes the occurrence and development of COPD. In recent years, the development of epigenetics and molecular biology have provided new guidance for revealing the pathogenesis, diagnosis, and treatment of diseases. The latest research indicates that pulmonary vascular endothelial cell apoptosis initiates and participates in the pathogenesis of COPD. In this review, we summarize the current research on the epigenetic mechanisms and molecular biology of CS-induced pulmonary vascular endothelial cell apoptosis in COPD, providing a new research direction for pathogenesis of COPD and a new target for the diagnosis, treatment, and prevention of COPD.

Targeting of glioma stem-like cells with a parthenolide derivative ACT001 through inhibition of AEBP1/PI3K/AKT signaling

Glioblastoma (GBM) is the most lethal primary brain tumor in adults with a median survival of around 15 months. A potential treatment strategy involves targeting glioma stem-like cells (GSCs) that are able to initiate, maintain, and repopulate the tumor mass. Here, we identify ACT001, a parthenolide derivative, targeting GSCs through regulation of adipocyte enhancer binding protein 1 (AEBP1) signaling.

Methods: The effects of ACT001 on cell survival of normal human astrocytes (NHA) and patient-derived glioma stem-like cells (GSCs) were evaluated. RNA-Seq were performed to detect differentially expressed genes. ACT001 efficacy as a single agent or in combination with SHP-2 inhibitor SHP099 was assessed using a GSC orthotopic xenograft model.

Results: GSCs exhibit high response to ACT001 in compared with normal human astrocytes. AEBP1 is a putative target of ACT001 by RNA-Seq analysis, which expression associates with prognosis of GBM patients. Knockdown of AEBP1 inhibits GSC proliferation and glioma sphere formation. Treatment with ACT001 or PI3K inhibitor or AEBP1 depletion would impair AKT phosphorylation and GSC proliferation, whereas constitutive AKT activation rescues ACT001 treatment or AEBP1 depletion-inhibited cell proliferation. Moreover, ACT001 blocks TGF-β-activated AEBP1/AKT signaling in GSCs. ACT001 exhibits antitumor activity either as a single agent or in combination with SHP099, which provides significant survival benefits for GSC tumor xenograft-bearing animals.

Conclusions: Our data demonstrate AEBP1 as a new druggable target in GBM and ACT001 as a potential therapeutic option for improving the clinical treatment of GBM in combination with SHP099.

Identification of long non-coding RNA signatures for squamous cell carcinomas and adenocarcinomas

Studies have demonstrated that both squamous cell carcinomas (SCCs) and adenocarcinomas (ACs) possess some common molecular characteristics. Evidence has accumulated to support the theory that long non-coding RNAs (lncRNAs) serve as novel biomarkers and therapeutic targets in complex diseases such as cancer.

In this study, we aimed to identify pan lncRNA signatures that are common to squamous cell carcinomas or adenocarcinomas with different tissues of origin. With the aid of elastic-net regularized regression models, a 35-lncRNA pan discriminative signature and an 11-lncRNA pan prognostic signature were identified for squamous cell carcinomas, whereas a 6-lncRNA pan discriminative signature and a 5-lncRNA pan prognostic signature were identified for adenocarcinomas. Among them, many well-known cancer relevant genes such as MALAT1 and PVT1 were included.

The identified pan lncRNA lists can help experimental biologists generate research hypotheses and adopt existing treatments for less prevalent cancers. Therefore, these signatures warrant further investigation.

Long noncoding RNA ASB16-AS1 inhibits adrenocortical carcinoma cell growth by promoting ubiquitination of RNA-binding protein HuR

Adrenocortical carcinoma is one of the aggressive malignancies and it originates from the cortex of adrenal gland. Dysregulation of long non-coding RNA plays important roles in the development of adrenocortical carcinoma. Here, we found that lncRNA ASB16-AS1 was down-regulated in adrenocortical carcinoma and ASB16-AS1 functions as tumor suppressor in vitro and in vivo. We then found that IGF1R and CDK6 are regulated by ASB16-AS1 in adrenocortical carcinoma cells by transcriptome RNA sequencing. ASB16-AS1 associates with RNA-binding protein HuR (ELAVL1) as revealed by RNA pull-down following mass spectrometry. Also, ASB16-AS1 inhibits HuR expression post-translationally by promoting its ubiquitination. ASB16-AS1 regulates IGF1R and CDK6 mRNA expression through RNA-binding protein HuR. We then found that inhibition of ASB16-AS1 attenuates the binding of ubiquitin E3 ligase BTRC to HuR and subsequently inhibits HuR protein unbiquitination and degradation. BTRC knock-down could reverse the effect of AB16-AS1 on HuR, CDK6, and IGF1R levels. Collectively, these results demonstrate that ASB16-AS1 regulates adrenocortical carcinoma cell proliferation and tackling the level of ASB16-AS1 may be developed to treat adrenocortical carcinoma.

LncRNA PPP1R14B-AS1 Promotes Tumor Cell Proliferation and Migration via the Enhancement of Mitochondrial Respiration

PPP1R14B-AS1 is an antisense long non-coding RNA with unknown functions. Herein, gene differential analyses were performed using the data of patients with liver cancer and lung adenocarcinoma (LUAD) from The Cancer Genome Atlas database. PPP1R14B-AS1 was found to be upregulated and also overexpressed in 10 other types of cancers. In addition, PPP1R14B-AS1 overexpression was associated with poor overall prognosis in eight cancers. Furthermore, PPPAR14B-AS1 upregulation was positively associated with worsening development of liver and LUAD cancers and related to poor disease-free survival. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses suggested that PPP1R14B-AS1 strongly participated in regulating cell aerobic respiration processes, such as mitochondrial electron respiration chain and NADH dehydrogenation processes. Cell cytoplasmic and nuclear RNA purification assessment results revealed that PPP1R14B-AS existed in the cell nucleus and cytoplasm. The knockdown of PPP1R14B-AS1 in HepG2 and A549 cells using PPP1R14B-AS1-specific siRNAs decreased mitochondrial respiration as demonstrated by the reduction in basal respiration and ATP production. Moreover, PPP1R14B-AS1 downregulation did not obviously affect cell glycolysis ability. Finally, PPP1R14B-AS1 inhibition inhibited HepG2 and A549 cell migration and proliferation. In summary, our study found for the first time that PPP1R14B-AS1 could be a potential biomarker for cancer diagnosis and that PPP1R14B-AS1 inhibition could be a potentially effective therapy.

EGR1-mediated linc01503 promotes cell cycle progression and tumorigenesis in gastric cancer

Objectives

Long non‐coding RNAs (lncRNAs) are key mediators in various malignancies. Linc01503 was previously elucidated to promote gastric cancer (GC) cell invasion. However, the upstream mechanism of linc01503 and its involvement in GC cell cycle, apoptosis and tumorigenesis still remain unclear.

Materials and Methods

Bioinformatics analysis and quantitative reverse transcription polymerase chain reaction (qRT‐PCR) assays were implicated to detect linc01503 level in GC. The role of linc01503 was detected by in vitro functional assays and in vivo xenograft tumour models. The association between linc01503 and its upstream effector was identified by chromatin immunoprecipitation (ChIP) assays. The mechanistic model of linc01503 was clarified using subcellular separation, fluorescence in situ hybridization, RNA‐sequencing, RNA immunoprecipitation (RIP) and ChIP assays.

Results

Linc01503 was remarkably elevated in GC and tightly linked with the overall survival of patients with GC. The key transcription factor early growth response protein 1 (EGR1) critically activated the transcription of linc01503. Functionally, linc01503 knockdown resulted in the activation of apoptosis and G1/G0 phase arrest in GC. Mechanistically, linc01503 interacted with histone modification enzyme enhancer of zeste 2 (EZH2) and lysine (K)‐specific demethylase 1A (LSD1), thereby mediating the transcriptional silencing of dual‐specificity phosphatase 5 (DUSP5) and cyclin‐dependent kinase inhibitor 1A (CDKN1A) in GC.

Conclusions

EGR1‐activated linc01503 could epigenetically silence DUSP5/CDKN1A expression to mediate cell cycle progression and tumorigenesis, implicating it as a prospective target for GC therapeutics.

Identification of Long Noncoding RNA Expression Profiles in HPV-Negative Cervical Cancer

AIM

HPV-negative cervical cancer (CC) usually appears more aggressive and causes poorer survival outcomes compared to HPV-positive cases. However, the research in regard to HPV-negative CC is rare, and the related molecular mechanism underlying remains unclear. We intended to explore the expression profiles of long noncoding RNAs (lncRNAs) and identify the tumor-associated lncRNAs which might be used as the potential biomarker for HPV-negative CC.

METHODS

Bioinformatics analyses were utilized to construct the expression profiles of lncRNAs, Gene Ontology, and KEGG analyses and draw the lncRNA-mRNA co-expression network in HPV-negative CC. The expression levels of the top 5 marked-up tumor-associated lncRNAs were detected by qRT-PCR. The effect of LINC00115 on CC growth and metastasis was studied by Cell Counting Kit-8 and transwell assays.

RESULTS

In comparison to normal cervix (NC), 2,052 lncRNAs were differentially expressed in HPV-negative CC. It demonstrated that LINC00115 was significantly upregulated in HPV-negative CC cells compared to NC, and it could promote proliferation, migration, and invasion of HPV-negative CC cells.

CONCLUSION

LINC00115 might be a potential biomarker for HPV-negative CC.

eQTL Colocalization Analyses Identify NTN4 as a Candidate Breast Cancer Risk Gene

Breast cancer genome-wide association studies (GWASs) have identified 150 genomic risk regions containing more than 13,000 credible causal variants (CCVs). The CCVs are predominantly noncoding and enriched in regulatory elements. However, the genes underlying breast cancer risk associations are largely unknown. Here, we used genetic colocalization analysis to identify loci at which gene expression could potentially explain breast cancer risk phenotypes. Using data from the Breast Cancer Association Consortium (BCAC) and quantitative trait loci (QTL) from the Genotype-Tissue Expression (GTEx) project and The Cancer Genome Project (TCGA), we identify shared genetic relationships and reveal novel associations between cancer phenotypes and effector genes. Seventeen genes, including NTN4, were identified as potential mediators of breast cancer risk. For NTN4, we showed the rs61938093 CCV at this region was located within an enhancer element that physically interacts with the NTN4 promoter, and the risk allele reduced NTN4 promoter activity. Furthermore, knockdown of NTN4 in breast cells increased cell proliferation in vitro and tumor growth in vivo. These data provide evidence linking risk-associated variation to genes that may contribute to breast cancer predisposition.