Over-expression of long noncoding RNA HOTAIRM1 promotes cell proliferation and invasion in human glioblastoma by up-regulating SP1 via sponging miR-137

Genetic Biomarkers in Astrocytoma: Diagnostic, Prognostic, and Therapeutic Potential

Astrocytoma is the most common adult brain tumor, with glioblastoma being the deadliest neuro-related malignancy. Despite advances in oncology, the prognosis for astrocytoma, especially glioblastoma, remains poor, and tracking disease progression is challenging due to a lack of robust biomarkers. Genetic biomarkers, including microRNAs, cell-free DNA, circulating tumor DNA, circular RNA, and long noncoding RNA, can serve as potential diagnostic and therapeutic targets. In this review, we examine the existing literature, analyzing the various less established liquid and tumor genetic biomarkers and their potential to act as diagnostic, prognostic, and therapeutic targets. We highlight the clinical challenges and limitations in implementing liquid biopsy strategies in clinical practice. The article discusses the potential of liquid biopsies as valuable tools for personalized astrocytoma management while emphasizing the need for standardized protocols and further advancements to establish their clinical utility and therapeutic application.

Glioblastoma stem cell long non-coding RNAs: therapeutic perspectives and opportunities

Glioblastoma poses a formidable challenge among primary brain tumors: its tumorigenic stem cells, capable of self-renewal, proliferation, and differentiation, contribute substantially to tumor initiation and therapy resistance. These glioblastoma stem cells (GSCs), resembling conventional stem and progenitor cells, adopt pathways critical for tissue development and repair, promoting uninterrupted tumor expansion. Long non-coding RNAs (lncRNAs), a substantial component of the human transcriptome, have garnered considerable interest for their pivotal roles in normal physiological processes and cancer pathogenesis. They display cell- or tissue-specific expression patterns, and extensive investigations have highlighted their impact on regulating GSC properties and cellular differentiation, thus offering promising avenues for therapeutic interventions. Consequently, lncRNAs, with their ability to exert regulatory control over tumor initiation and progression, have emerged as promising targets for innovative glioblastoma therapies. This review explores notable examples of GSC-associated lncRNAs and elucidates their functional roles in driving glioblastoma progression. Additionally, we delved deeper into utilizing a 3D in vitro model for investigating GSC biology and elucidated four primary methodologies for targeting lncRNAs as potential therapeutics in managing glioblastoma.

The Talented LncRNAs: Meshing into Transcriptional Regulatory Networks in Cancer

As a group of diseases characterized by uncontrollable cell growth, cancer is highly multifaceted in how it overrides checkpoints controlling proliferation. Amongst the regulators of these checkpoints, long non-coding RNAs (lncRNAs) can have key roles in why natural biological processes go haywire. LncRNAs represent a large class of regulatory transcripts that can localize anywhere in cells. They were found to affect gene expression on many levels from transcription to mRNA translation and even protein stability. LncRNA participation in such control mechanisms can depend on cell context, with given transcripts sometimes acting as oncogenes or tumor suppressors. Importantly, the tissue-specificity and low expression levels of lncRNAs make them attractive therapeutic targets or biomarkers. Here, we review the various cellular processes affected by lncRNAs and outline molecular strategies they use to control gene expression, particularly in cancer and in relation to transcription factors.

Specificity Proteins (Sp) and Cancer

The specificity protein (Sp) transcription factors (TFs) Sp1, Sp2, Sp3 and Sp4 exhibit structural and functional similarities in cancer cells and extensive studies of Sp1 show that it is a negative prognostic factor for patients with multiple tumor types. In this review, the role of Sp1, Sp3 and Sp4 in the development of cancer and their regulation of pro-oncogenic factors and pathways is reviewed. In addition, interactions with non-coding RNAs and the development of agents that target Sp transcription factors are also discussed. Studies on normal cell transformation into cancer cell lines show that this transformation process is accompanied by increased levels of Sp1 in most cell models, and in the transformation of muscle cells into rhabdomyosarcoma, both Sp1 and Sp3, but not Sp4, are increased. The pro-oncogenic functions of Sp1, Sp3 and Sp4 in cancer cell lines were studied in knockdown studies where silencing of each individual Sp TF decreased cancer growth, invasion and induced apoptosis. Silencing of an individual Sp TF was not compensated for by the other two and it was concluded that Sp1, Sp3 and Sp4 are examples of non-oncogene addicted genes. This conclusion was strengthened by the results of Sp TF interactions with non-coding microRNAs and long non-coding RNAs where Sp1 contributed to pro-oncogenic functions of Sp/non-coding RNAs. There are now many examples of anticancer agents and pharmaceuticals that induce downregulation/degradation of Sp1, Sp3 and Sp4, yet clinical applications of drugs specifically targeting Sp TFs are not being used. The application of agents targeting Sp TFs in combination therapies should be considered for their potential to enhance treatment efficacy and decrease toxic side effects.

The long non-coding RNA HOTAIRM1 promotes tumor aggressiveness and radiotherapy resistance in glioblastoma

Glioblastoma is the most common malignant primary brain tumor. To date, clinically relevant biomarkers are restricted to isocitrate dehydrogenase (IDH) gene 1 or 2 mutations and O6-methylguanine DNA methyltransferase (MGMT) promoter methylation. Long non-coding RNAs (lncRNAs) have been shown to contribute to glioblastoma pathogenesis and could potentially serve as novel biomarkers. The clinical significance of HOXA Transcript Antisense RNA, Myeloid-Specific 1 (HOTAIRM1) was determined by analyzing HOTAIRM1 in multiple glioblastoma gene expression data sets for associations with prognosis, as well as, IDH mutation and MGMT promoter methylation status. Finally, the role of HOTAIRM1 in glioblastoma biology and radiotherapy resistance was characterized in vitro and in vivo. We identified HOTAIRM1 as a candidate lncRNA whose up-regulation is significantly associated with shorter survival of glioblastoma patients, independent from IDH mutation and MGMT promoter methylation. Glioblastoma cell line models uniformly showed reduced cell viability, decreased invasive growth and diminished colony formation capacity upon HOTAIRM1 down-regulation. Integrated proteogenomic analyses revealed impaired mitochondrial function and determination of reactive oxygen species (ROS) levels confirmed increased ROS levels upon HOTAIRM1 knock-down. HOTAIRM1 knock-down decreased expression of transglutaminase 2 (TGM2), a candidate protein implicated in mitochondrial function, and knock-down of TGM2 mimicked the phenotype of HOTAIRM1 down-regulation in glioblastoma cells. Moreover, HOTAIRM1 modulates radiosensitivity of glioblastoma cells both in vitro and in vivo. Our data support a role for HOTAIRM1 as a driver of biological aggressiveness, radioresistance and poor outcome in glioblastoma. Targeting HOTAIRM1 may be a promising new therapeutic approach.

HOTAIRM1 Promotes Malignant Progression of Transformed Fibroblasts in Glioma Stem-Like Cells Remodeled Microenvironment via Regulating miR-133b-3p/TGFβ Axis

Recent studies have reported that cancer associated fibroblasts (CAFs) and glioma stem-like cells (GSCs) played active roles in glioma progression in tumor microenvironment (TME). Long non-coding RNAs (lncRNAs) have been found to be closely associated with glioma development in recent years, however, their molecular regulatory mechanisms on CAFs in GSCs remodeled TME kept largely unelucidated. Our study found that GSCs could induce malignant transformation of fibroblasts (t-FBs) based on dual-color fluorescence tracing orthotopic model. Associated with poor prognosis, Lnc HOXA transcript antisense RNA, myeloid-specific 1 (HOTAIRM1) was highly expressed in high-grade gliomas and t-FBs. Depleting HOTAIRM1 inhibited the proliferation, invasion, migration, and even tumorigenicity of t-FB. Conversely, overexpression of HOTAIRM1 promoted malignancy phenotype of t-FB. Mechanistically, HOTAIRM1 directly bound with miR-133b-3p, and negatively regulated the latter. MiR-133b-3p partly decreased the promotion effect of HOTAIRM1 on t-FBs. Furthermore, transforming growth factor-β (TGFβ) was verified to be a direct target of miR-133b-3p. HOTAIRM1 can modulate TGFβ via competing with miR-133b-3p. Collectively, HOTAIRM1/miR-133b-3p/TGFβ axis was involved in modulating t-FBs malignancy in TME remodeled by GSCs, which had the potential to serve as a target against gliomas.

LncRNA HOTAIRM1 knockdown inhibits cell glycolysis metabolism and tumor progression by miR-498/ABCE1 axis in non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) is a major contributor of cancer-related mortality. Long non-coding RNAs (lncRNAs) are indicated to participate in the pathogenesis of NSCLC.

OBJECTIVE

In this research, the effects of lncRNA HOXA transcript antisense RNA, myeloid-specific 1 (HOTAIRM1) on NSCLC progression and underlying mechanism were revealed.

METHODS

The expression levels of HOTAIRM1 and microRNA-498 (miR-498) were detected by quantitative real time polymerase chain reaction (qRT-PCR) in NSCLC tissues, cells or exosomes. The protein expression of CD63, CD81, hexokinase 2 (HK2) and ATP binding cassette subfamily E member 1 (ABCE1) was determined by western blot. Cell viability, apoptosis, migration and invasion were investigated by cell counting kit-8 (CCK-8), flow cytometry, transwell migration and invasion assays, respectively. Cell glycolysis metabolism was revealed by glucose uptake and lactate production assays and western blot analysis. The binding relationship between miR-498 and HOTAIRM1 or ABCE1 was predicted by DIANA-LncBase v2 and starBase online database, and identified by dual-luciferase reporter assay. The effects of HOTAIRM1 on NSCLC growth in vivo were revealed by in vivo tumor formation assay.

RESULTS

HOTAIRM1 expression was dramatically upregulated, whereas miR-498 expression was significantly downregulated in NSCLC tissues cells or exosomes as compared to control groups. Mechanistically, HOTAIRM1 knockdown repressed cell viability, migration, invasion and glycolysis metabolism, whereas induced cell apoptosis in NSCLC; however, miR-498 inhibitor hindered these effects. Functionally, HOTAIRM1 functioned as a sponge of miR-498 and miR-498 targeted ABCE1. In addition, HOTAIRM1 silencing inhibited NSCLC growth in vivo by downregulating ABCE1 and upregulating miR-498 expression.

CONCLUSIONS

HOTAIRM1 knockdown repressed cell glycolysis metabolism and tumor development by reducing ABCE1 expression through sponging miR-498 in NSCLC, which provided a theoretical basis for further studying NSCLC progression.

Long Noncoding RNA Expression in Adrenal Cortical Neoplasms

Long noncoding RNAs (lncRNAs) consist of nucleic acid molecules that are greater than 200 nucleotides in length and they do not code for specific proteins. A growing body of evidence indicates that these lncRNAs have important roles in tumorigenesis. Separating adrenal cortical adenomas from carcinomas is often a difficult problem for the surgical pathologist. This is especially true when only small needle biopsies are available for examination. We used in situ hybridization (ISH) analysis to study normal adrenal cortical tissues and adrenal cortical tumors to determine the role of specific lncRNAs in tumor development and classification. The lncRNAS studied included metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), psoriasis susceptibility-related RNA gene induced by stress (PRINS), and HOX antisense intergenic RNA myeloid 1 (HAM1). We constructed a tissue microarray (TMA) for the studies and also analyzed a subset of cases by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Two 1-mm duplicate cores of normal adrenal cortex (NAC) (n = 23), adrenal cortical adenomas (ACAs) (n = 95), and adrenal cortical carcinomas (ACCs), (n = 20) were used on the TMA. The results of ISH were analyzed by image analysis. ISH showed predominantly nuclear expression of lncRNAs in adrenal cortical tissues. MALAT1 showed more expression in ACCs than in NAC and ACA (p < 0.05). PRINS had higher expression in NACs and ACAs than in ACCs. The lncRNAs MALAT1, PRINS, and HAM1 are all expressed in normal and neoplastic adrenal cortical tissues. MALAT1 had the highest expression in ACC compared to ACAs and may have a role in ACC development.

Long Non-Coding RNA NCK1-AS1 Serves an Oncogenic Role in Gastric Cancer by Regulating miR-137/NUP43 Axis

Introduction

Long non-coding RNA (lncRNA) NCK1-AS1 could regulate multiple cancer progression. However, little is known regarding the roles and acting mechanisms of NCK-AS1 in gastric cancer (GC) progression. This work was aimed to explore the relationship between NCK1-AS1 and GC progression to illustrate the mechanisms of NCK1-AS1.

Methods

NCK1-AS1 expression level in GC tissues and cells was measured with a quantitative real-time PCR method. In vitro experiments including cell counting kit-8 assay, colony formation assay, wound-healing assay, and transwell invasion assay were employed to detect biological roles of NCK1-AS1 in GC progression. In vivo experiments were performed to analyze the roles of NCK1-AS1 on GC malignant phenotype. Moreover, mechanisms behind the biological roles of NCK1-AS1 in GC were investigated using bioinformatic analysis, luciferase activity reporter assay, RNA immunoprecipitation assay, and rescue experiments.

Results

NCK1-AS1 was found to have elevated expression in GC tissues and cells in comparison with normal counterparts. Loss-of-function experiments showed knockdown of NCK1-AS1 refrained GC cell proliferation, colony formation, migration, and invasion in vitro. Animal experiments showed silence of NCK1-AS1 suppresses tumor growth in vivo. Functionally, NCK1-AS1 serves as a sponge for microRNA-137 (miR-137) to upregulate nucleoporin 43 (NUP43) expression in GC. Rescue experiments proved the carcinogenic role of NCK1-AS1/miR-137/NUP43 axis in GC progression.

Discussion

In conclusion, the NCK1-AS1/miR-137/NUP43 axis was identified that could contribute to GC malignancy behaviors.

Long noncoding RNA HOTAIRM1 in human cancers

Long noncoding RNAs (lncRNAs) are a group of RNAs over 200 nucleotides in length involved in diverse processes in tumor cells including proliferation, invasion and apoptosis. Given these facts, it is hardly accidental that variations in the expression of some lncRNAs have been found to be closely related to carcinogenesis and tumor growth and metastasis. HOTAIRM1, first discovered as an important factor for granulocytic differentiation in NB4 promyelocytic leukemia, has been shown to be a salient cancer-related lncRNA abnormally expressed in a variety of tumors. In this review, we summarize current evidence on the critical role of HOTAIRM1 in human malignancy, its potential mechanism of action and future use in the development of effective therapeutics.

Long Noncoding RNA WEE2-AS1 Plays an Oncogenic Role in Glioblastoma by Functioning as a Molecular Sponge for MicroRNA-520f-3p

The long noncoding RNA WEE2 antisense RNA 1 (WEE2-AS1) plays an oncogenic role in hepatocellular carcinoma and triple negative breast cancer progression. In this study, we investigated the expression and roles of WEE2-AS1 in glioblastoma (GBM). Furthermore, the molecular mechanisms behind the oncogenic actions of WEE2-AS1 in GBM cells were explored in detail. WEE2-AS1 expression was detected using quantitative real-time polymerase chain reaction. The roles of WEE2-AS1 in GBM cells were evaluated by the cell counting kit-8 assay, flow cytometric analysis, Transwell cell migration and invasion assays, and tumor xenograft experiments. WEE2-AS1 expression was evidently enhanced in GBM tissues and cell lines compared with their normal counterparts. An increased level of WEE2-AS1 was correlated with the average tumor diameter, Karnofsky Performance Scale score, and shorter overall survival among GBM patients. Functionally, depleted WEE2-AS1 attenuated GBM cell proliferation, migration, and invasion in vitro, promoted cell apoptosis, and impaired tumor growth in vivo. Mechanistically, WEE2-AS1 functioned as a molecular sponge for microRNA-520f-3p (miR-520f-3p) and consequently increased specificity protein 1 (SP1) expression in GBM cells. A series of recovery experiments revealed that the inhibition of miR-520f-3p and upregulation of SP1 could partially abrogate the influences of WEE2-AS1 downregulation on GBM cells. In conclusion, WEE2-AS1 can adsorb miR-520f-3p to increase endogenous SP1 expression, thereby facilitating the malignancy of GBM. Therefore, targeting the WEE2-AS1–miR-520f-3p–SP1 pathway might be a promising therapy for the management of GBM in the future.

miR-137: A Novel Therapeutic Target for Human Glioma

MicroRNA (miR)-137 is highly expressed in the brain and plays a crucial role in the development and prognosis of glioma. In this review, we aim to summarize the latest findings regarding miR-137 in glioma cell apoptosis, proliferation, migration, invasion, angiogenesis, drug resistance, and cancer treatment. In addition, we focus on the identified miR-137 targets and pathways in the occurrence and development of glioma. Finally, future implications for the diagnostic and therapeutic potential of miR-137 in glioma were discussed.