Long Non-Coding RNAs in Diagnosis, Treatment, Prognosis, and Progression of Glioma: A State-of-the-Art Review

Relationship between lncRNA MALAT1 and Chemo-radiotherapy Resistance of Cancer Cells: Uncovered Truths

The advancement of novel technologies, coupled with bioinformatics, has led to the discovery of additional genes, such as long noncoding RNAs (lncRNAs), that are associated with drug resistance. LncRNAs are composed of over 200 nucleotides and do not possess any protein coding function. These lncRNAs exhibit lower conservation across species, are typically expressed at low levels, and often display high specificity towards specific tissues and developmental stages. The LncRNA MALAT1 plays crucial regulatory roles in various aspects of genome function, encompassing gene transcription, splicing, and epigenetics. Additionally, it is involved in biological processes related to the cell cycle, cell differentiation, development, and pluripotency. Recently, MALAT1 has emerged as a novel mechanism contributing to drug resistance or sensitivity, attracting significant attention in the field of cancer research. This review aims to explore the mechanisms through which MALAT1 confers resistance to chemotherapy and radiotherapy in cancer cells.

Glycolysis‑related lncRNA may be associated with prognosis and immune activity in grade II‑III glioma

Glucose metabolism, as a novel theory to explain tumor cell behavior, has been intensively studied in various tumors. The present study explored the long non-coding RNAs (lncRNAs) related to glycolysis in grade II-III glioma, aiming to provide a promising target for further research. Pearson correlation analysis was used to identify glycolysis-related lncRNAs. Univariate/multivariate Cox regression analysis and the Least Absolute Shrinkage and Selection Operator algorithm were applied to identify glycolysis-related lncRNAs to construct a prognosis prediction model. Subsequently, multi-dimensional evaluations were used to verify whether the risk model could predict the prognosis and survival rate of patients with grade II-III glioma. Finally, it was verified by functional experiments. The present study finally identified seven glycolysis-related lncRNAs (CRNDE, AC022034.1, RHOQ-AS1, AL159169.2, AL133215.2, AC007098.1 and LINC02587) to construct a prognosis prediction model. The present study further investigated the underlying immune microenvironment, somatic landscape and functional enrichment pathways. Additionally, individualized immunotherapeutic strategies and candidate compounds were identified to guide clinical treatment. The experimental results demonstrated that CRNDE could increase the proliferation of SHG-44 cells. In conclusion, a large sample of human grade II-III glioma in The Cancer Genome Atlas database was used to construct a risk model using glycolysis-related lncRNAs to predict the prognosis of patients with grade II-III glioma.

Long non-coding RNA H19 regulates neurogenesis of induced neural stem cells in a mouse model of closed head injury

Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury. We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement. However, the neural regeneration efficiency of induced neural stem cells remains limited. In this study, we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells. We found that H19 was the most downregulated neurogenesis-associated lncRNA in induced neural stem cells compared with induced pluripotent stem cells. Additionally, we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons. We predicted the target genes of H19 and discovered that H19 directly interacts with miR-325-3p, which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells. Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation, and miR-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition. Furthermore, H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells. Notably, silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice. Our results reveal that H19 regulates the neurogenesis of induced neural stem cells. H19 inhibition may promote the neural differentiation of induced neural stem cells, which is closely associated with neurological recovery following closed head injury.

Exosomal long non-coding RNAs in glioblastoma

Glioblastoma multiforme (GBM) is the most prevalent primary tumor found in the central nervous system, accounting for 70% of all adult brain tumors. The median overall survival rate is one year post-diagnosis with treatment, and only four months without treatment. Current GBM diagnostic methods, such as magnetic resonance imaging (MRI), surgery, and brain biopsies, have limitations. These include difficulty distinguishing between tumor recurrence and post-surgical necrotic regions, and operative risks associated with obtaining histological samples through direct surgery or biopsies. Consequently, there is a need for rapid, inexpensive, and minimally invasive techniques for early diagnosis and improved subsequent treatment. Research has shown that tumor-derived exosomes containing various long non-coding RNAs (lncRNAs) play critical regulatory roles in immunomodulation, cancer metastasis, cancer development, and drug resistance in GBM. They regulate genes that enhance cancer growth and progression and alter the expression of several key signaling pathways. Due to the specificity and sensitivity of exosomal lncRNAs, they have the potential to be used as biomarkers for early diagnosis and prognosis, as well as to monitor a patient's response to chemotherapy for GBM. In this review, we discuss the role of exosomal lncRNAs in the pathogenesis of GBM and their potential clinical applications for early diagnosis.

Non-coding RNAs regulating endothelial progenitor cells for venous thrombosis: promising therapy and innovation

Venous thromboembolism, which includes deep venous thrombosis (DVT) and pulmonary embolism, is the third most common vascular disease in the world and seriously threatens the lives of patients. Currently, the effect of conventional treatments on DVT is limited. Endothelial progenitor cells (EPCs) play an important role in the resolution and recanalization of DVT, but an unfavorable microenvironment reduces EPC function. Non-coding RNAs, especially long non-coding RNAs and microRNAs, play a crucial role in improving the biological function of EPCs. Non-coding RNAs have become clinical biomarkers of diseases and are expected to serve as new targets for disease intervention. A theoretical and experimental basis for the development of new methods for preventing and treating DVT in the clinic will be provided by studies on the role and molecular mechanism of non-coding RNAs regulating EPC function in the occurrence and development of DVT. To summarize, the characteristics of venous thrombosis, the regulatory role of EPCs in venous thrombosis, and the effect of non-coding RNAs regulating EPCs on venous thrombosis are reviewed. This summary serves as a useful reference and theoretical basis for research into the diagnosis, prevention, treatment, and prognosis of venous thrombosis.

The role and clinical relevance of long non-coding RNAs in glioma

Glioma represents a complex and heterogeneous disease, posing significant challenges to both clinicians and researchers. Despite notable advancements in glioma treatment, the overall survival rate for most glioma patients remains dishearteningly low. Hence, there is an urgent necessity to discover novel biomarkers and therapeutic targets specifically tailored for glioma. In recent years, long non-coding RNAs (lncRNAs) have emerged as pivotal regulators of gene expression and have garnered attention for their involvement in the development and progression of various cancers, including glioma. The dysregulation of lncRNAs plays a critical role in glioma pathogenesis and influences clinical outcomes. Consequently, there is growing interest in exploring the potential of lncRNAs as diagnostic and prognostic biomarkers, as well as therapeutic targets. By understanding the functions and dysregulation of lncRNAs in glioma, researchers aim to unlock new avenues for the development of innovative treatment strategies catered to glioma patients. The identification and thorough characterization of lncRNAs hold the promise of novel therapeutic approaches that could potentially improve patient outcomes and enhance the management of glioma, ultimately striving for better prospects and enhanced quality of life for those affected by this challenging disease. The primary objective of this paper is to comprehensively review the current state of knowledge regarding lncRNA biology and their intricate roles in glioma. It also delves into the potential of lncRNAs as valuable diagnostic and prognostic indicators and explores their feasibility as promising targets for therapeutic interventions.

Silencing of the MEG3 gene promoted anti-cancer activity and drug sensitivity in glioma

Aberrant expression of MEG3 has been shown in various cancers. The purpose of this study is to evaluate the effect of MEG3 on glioma cells and the use of potential chemotherapeutics in glioma by modulating MEG3 expression. Cell viability, migration and chemosensitivity were assayed. Cell death was evaluated in MEG3 overexpressing and MEG3 suppressed cells. MEG3 expression was compared in patient-derived glioma cells concerning IDH1 mutation and WHO grades. Silencing of MEG3 inhibited cell proliferation and reduced cell migration while overexpression of MEG3 promoted proliferation in glioma cells. MEG3 inhibition improved the chemosensitivity of glioma cells to 5-fluorouracil (5FU) but not to navitoclax. On the other hand, there is no significant effect of MEG3 expression on temozolamide (TMZ) treatment which is a standard chemotherapeutic agent in glioma. Suppression of the MEG3 gene in patient-derived oligodendroglioma cells also showed the same effect whereas glioblastoma cell proliferation and chemosensitivity were not affected by MEG3 inhibition. Further, as a possible cell death mechanism of action apoptosis was investigated. Although MEG3 is a widely known tumour suppressor gene and its loss is associated with several cancer types, here we reported that MEG3 inhibition can be used for improving the efficiency of known chemotherapeutic drug sensitivity. We propose that the level of MEG3 should be evaluated in the treatment of different glioma subtypes that are resistant to effective drugs to increase the potential effective drug applications.

Long non-coding RNA H19: a potential biomarker and therapeutic target in human malignant tumors

Long non-coding RNAs play important roles in cellular functions and disease development. H19, as a long non-coding RNA, is pervasively over-expressed in almost all kinds of human malignant tumors. Although many studies have reported that H19 is closely associated with tumor cell proliferation, apoptosis, invasion, metastasis, and chemoresistance, the role and mechanism of H19 in gene regulation and tumor development are largely unclear. In this review, we summarized the recent progress in the study of the major functions and mechanisms of H19 lncRNA in cancer development and progression. H19 possesses both oncogenic and tumor-suppressing activities, presumably through regulating target gene transcription, mRNA stability and splicing, and competitive inhibition of endogenous RNA degradation. Studies indicate that H19 may involve in cell proliferation and apoptosis, tumor initiation, migration, invasion, metastasis and chemoresistance and may serve as a potential biomarker for early diagnosis, prognosis, and novel molecular target for cancer therapy.

Crosstalk between SOX Genes and Long Non-Coding RNAs in Glioblastoma

Glioblastoma (GBM) continues to be the most devastating primary brain malignancy. Despite significant advancements in understanding basic GBM biology and enormous efforts in developing new therapeutic approaches, the prognosis for most GBM patients remains poor with a median survival time of 15 months. Recently, the interplay between the SOX (SRY-related HMG-box) genes and lncRNAs (long non-coding RNAs) has become the focus of GBM research. Both classes of molecules have an aberrant expression in GBM and play essential roles in tumor initiation, progression, therapy resistance, and recurrence. In GBM, SOX and lncRNAs crosstalk through numerous functional axes, some of which are part of the complex transcriptional and epigenetic regulatory mechanisms. This review provides a systematic summary of current literature data on the complex interplay between SOX genes and lncRNAs and represents an effort to underscore the effects of SOX/lncRNA crosstalk on the malignant properties of GBM cells. Furthermore, we highlight the significance of this crosstalk in searching for new biomarkers and therapeutic approaches in GBM treatment.

Association of altered metabolic profiles and long non-coding RNAs expression with disease severity in breast cancer patients: analysis by 1H NMR spectroscopy and RT-q-PCR

INTRODUCTION

Globally, one of the major causes of cancer related deaths in women is breast cancer. Although metabolic pattern is altered in cancer patients, robust metabolic biomarkers with a potential to improve the screening and disease monitoring are lacking. A complete metabolome profiling of breast cancer patients may lead to the identification of diagnostic/prognostic markers and potential targets.

OBJECTIVES

The aim of this study was to analyze the metabolic profile in the serum from 43 breast cancer patients and 13 healthy individuals.

MATERIALS & METHODS

We used ¹H NMR spectroscopy for the identification and quantification of metabolites. q-RT-PCR was used to examine the relative expression of lncRNAs.

RESULTS

Metabolites such as amino acids, lipids, membrane metabolites, lipoproteins, and energy metabolites were observed in the serum from both patients and healthy individuals. Using unsupervised PCA, supervised PLS-DA, supervised OPLS-DA, and random forest classification, we observed that more than 25 metabolites were altered in the breast cancer patients. Metabolites with AUC value > 0.9 were selected for further analysis that revealed significant elevation of lactate, LPR and glycerol, while the level of glucose, succinate, and isobutyrate was reduced in breast cancer patients in comparison to healthy control. The level of these metabolites (except LPR) was altered in advanced-stage breast cancer patients in comparison to early-stage breast cancer patients. The altered metabolites were also associated with over 25 signaling pathways related to metabolism. Further, lncRNAs such as H19, MEG3 and GAS5 were dysregulated in the breast tumor tissue in comparison to normal adjacent tissue.

CONCLUSION

The study provides insights into metabolic alteration in breast cancer patients. It also provides an avenue to examine the association of lncRNAs with metabolic patterns in patients.

TUG1 aggravates intracerebral hemorrhage injury by inhibiting angiogenesis in an miR-26a-dependent manner

Long non-coding RNA taurine-upregulated gene 1 (TUG1) plays pivotal roles in angiogenesis, an important mechanism of neural repair after intracerebral hemorrhage (ICH). However, the role of TUG1 in angiogenesis following ICH is not clear. Therefore, in this study, we investigated the role and the underlying mechanism of TUG1 in neurologic impairment and cerebral angiogenesis following ICH. The ICH rat model was established and then rats were injected with TUG1-expressing plasmid (pcDNA-TUG1) or miR-26a mimic, a critical regulator of VEGF-mediated angiogenesis. We confirmed the overexpression of TUG1 and miR-26a by qRT-PCR. The neurological deficits of ICH rats were evaluated by modified neurological severity scores. The expression of angiogenesis markers VEGF and CD31 were examined by immunohistochemistry and western blot. The interaction between TUG1 and miR-26a was determined by luciferase reporter assay. Our results showed that ICH caused a marked upregulation of TUG1 and a significant downregulation of miR-26a. TUG1 overexpression led to the deterioration of neurologic function and inhibited cerebral angiogenesis in ICH rats. In contrast, overexpression of miR-26a alleviated the neurologic damage and promoted cerebral angiogenesis in ICH rats, but these could be attenuated by TUG1 overexpression. Furthermore, TUG1 directly bound to miR-26a and inhibited its expression. Importantly, TUG1 overexpression inhibited the expression of VEGF by targeting miR-26a. In conclusion, our results indicated that TUG1 aggravated ICH-mediated injury by suppressing angiogenesis by downregulating miR-26a. This suggests a rationale for targeting TUG1/miR-26a in the therapy of ICH.

LncRNA MEG3: Potential stock for precision treatment of cardiovascular diseases

The prevalence and mortality rates of cardiovascular diseases are increasing, and new treatment strategies are urgently needed. From the perspective of basic pathogenesis, the occurrence and development of cardiovascular diseases are related to inflammation, apoptosis, fibrosis and autophagy of cardiomyocytes, endothelial cells and other related cells. The involvement of maternally expressed gene 3 (MEG3) in human disease processes has been increasingly reported. P53 and PI3K/Akt are important pathways by which MEG3 participates in regulating cell apoptosis. MEG3 directly or competitively binds with miRNA to participate in apoptosis, inflammation, oxidative stress, endoplasmic reticulum stress, EMT and other processes. LncRNA MEG3 is mainly involved in malignant tumors, metabolic diseases, immune system diseases, cardiovascular and cerebrovascular diseases, etc., LncRNA MEG3 has a variety of pathological effects in cardiomyocytes, fibroblasts and endothelial cells and has great clinical application potential in the prevention and treatment of AS, MIRI, hypertension and HF. This paper will review the research progress of MEG3 in the aspects of mechanism of action, other systemic diseases and cardiovascular diseases, and point out its great potential in the prevention and treatment of cardiovascular diseases. lncRNAs also play a role in endothelial cells. In addition, lncRNA MEG3 has shown biomarker value, prognostic value and therapeutic response measurement in tumor diseases. We boldly speculate that MEG3 will play a role in the emerging discipline of tumor heart disease.

Association of Polymorphisms in the Long Non-Coding RNA HOTAIR with Recurrent Pregnancy Loss in a Korean Population

Recurrent pregnancy loss (RPL) affects 1% to 5% of women, with devastating effects on both reproductive health and psychological well-being. Homeobox (HOX) transcript antisense RNA (HOTAIR) is a long non-coding RNA (lncRNA) produced by HOXC; it plays a major role in invasion and development of ovarian and other cancers. The aim of the present study was to analyze effects of HOTAIR polymorphisms (rs4759314 A>G, rs920778 T>C, rs1899663 G>T, and rs7958904 G>C) on RPL in Korean women. A total of 403 women with RPL and 383 healthy women were selected for this study. Genotyping analysis was performed with the polymerase chain reaction, restriction fragment length polymorphism, and the TaqMan genotyping assay. Clinical characteristics were compared using Student's unpaired t-test and the chi-square test for categorical variables. Logistic regression was performed to evaluate associations between single nucleotide polymorphisms and RPL incidence. In all assays, p < 0.05 was considered significant. HOTAIR polymorphisms rs4759314A>G and rs920778T>C were highly associated with increased risk of RPL, specifically the haplotypes rs4759314A>G/rs1899663G>T (G-T) and rs4759314A>G/rs920778 T>C (G-C). These associations were maintained in haplotypes that contained three polymorphisms (rs4759314 A>G, rs920778 T>C, and rs1899663 G>T) A-C-G, G-T-G, and G-T-T, further indicating that the HOTAIR rs4759314 and rs920778 polymorphisms play significant roles in idiopathic RPL in Korean women.

Emerging trends and research foci of epithelial–mesenchymal transition in gliomas: A scientometric analysis and review

Background

Epithelial–mesenchymal transition (EMT) is a key factor in the invasion and migration of glioma cells, and the study of EMT in gliomas has become a hot topic over the past decade. Scientometric analysis is gaining more attention since it can obtain hot topics and emerging trends in a research field. This article analyzed the research related to EMT in gliomas for the first time, including descriptions of research situations, evaluations of research foci, and predictions of emerging trends.

Methods

We searched the topic-related original articles from January 2012 to December 2021 in the Web of Science Core Collection (WoSCC) by using a specific strategy, and a total of 1,217 publications were obtained. The WoS platform, VOS viewer, and CiteSpace were used to analyze the annual distribution of publications and citations, authors and density of keywords, and other analyses including countries, institutions, references, clustering, burst analysis, and the timeline view of keywords.

Results

Scientometric analysis identified that the study of EMT in gliomas has developed fast and received continuous attention in the last decade. Based on the results of data analysis, most publications on the topic came from China, and the United States had the highest betweenness centrality. The top 10 co-cited references revealed the landmark documents that had greatly promoted the development of this field. The major focus is on the cellular and molecular mechanisms of EMT in gliomas, and the therapy related to EMT target and non-coding RNAs has been developing fast in recent years.

Conclusions

This study revealed the intimate connections between EMT and gliomas, and the complex mechanisms regulating EMT in gliomas had been studied widely in the last decade. Exploring the deep mechanisms of EMT in gliomas is the foundation of the targeted inhibitions, which can promote the development of therapies for gliomas.

Identification of Prognostic LncRNAs Subtypes Predicts Prognosis and Immune Microenvironment for Glioma

Glioma is the most commonly occurring primary neuroepithelial neoplasm. Long noncoding RNAs (lncRNAs) are emerging as pivotal modulators of gene expression in the immune system and play critical roles in the growth, progression, and immune response of carcinomas. In this study, we performed univariate Cox regression analysis on survival data from TCGA and identified 20 prognostic lncRNAs. Moreover, we revealed that these prognosis-related lncRNAs (PRLnc) were dysregulated in glioma. Furthermore, we constructed a signature based on the expression levels of these prognosis-related lncRNAs based on 13 prognostic lncRNAs, including AGAP2-AS1, CYTOR, MIR155HG, LINC00634, HOTAIRM1, SNHG18, LINC01841, LINC01842, LINC01426, MIR9-3HG, TMEM220-AS1, LINC00641, LINC01270, and LINC01503. The Kaplan–Meier curves show that high-risk patients had a shorter survival time. Finally, the glioma samples were classified into 2 subgroups based on the median expression of prognosis-related lncRNAs in each sample. In summary, these findings suggest that PRLnc is associated with tumor-infiltrating immune cells in glioma and that subtype 2 patients may respond more positively to immunotherapy.

An Axis between the Long Non-Coding RNA HOXA11-AS and NQOs Enhances Metastatic Ability in Oral Squamous Cell Carcinoma

Long non-coding RNAs (lncRNAs) play critical roles in human cancers. HOXA11 anti-sense RNA (HOXA11-AS) is an lncRNA belonging to the homeobox (HOX) gene cluster that promotes liver metastasis in human colon cancer. However, its role and mechanism of action in human oral squamous cell carcinoma (OSCC) are unclear. In this study, we investigated HOXA11-AS expression and function in human OSCC tissues and cell lines, as well as a mouse model of OSCC. Our analyses showed that HOXA11-AS expression in human OSCC cases correlates with lymph node metastasis, nicotinamide adenine dinucleotide (NAD)(P)H: quinone oxidoreductase 1 (NQO1) upregulation, and dihydronicotinamide riboside (NRH): quinone oxidoreductase 2 (NQO2) downregulation. Using the human OSCC cell lines HSC3 and HSC4, we demonstrate that HOXA11-AS promotes NQO1 expression by sponging microRNA-494. In contrast, HOXA11-AS recruits zeste homolog 2 (EZH2) to the NQO2 promoter to suppress its expression via the trimethylation of H3K27. The upregulation of NQO1 enzymatic activity by HOXA11-AS results in the consumption of flavin adenine dinucleotide (FAD), which reduces FAD-requiring glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity and suppresses glycolysis. However, our analyses show that lactic acid fermentation levels are preserved by glutaminolysis due to increased malic enzyme-1 expression, promoting enhanced proliferation, invasion, survival, and drug resistance. In contrast, suppression of NQO2 expression reduces the consumption of NRH via NQO2 enzymatic activity and increases NAD levels, which promotes enhanced stemness and metastatic potential. In mouse tumor models, knockdown of HOXA11-AS markedly suppressed tumor growth and lung metastasis. From these findings, targeting HOXA11-AS may strongly suppress high-grade OSCC by regulating both NQO1 and NQO2.

Post-Transcriptional Modifications of RNA as Regulators of Apoptosis in Glioblastoma

This review is devoted to changes in the post-transcriptional maturation of RNA in human glioblastoma cells, which leads to disruption of the normal course of apoptosis in them. The review thoroughly highlights the latest information on both post-transcriptional modifications of certain regulatory RNAs, associated with the process of apoptosis, presents data on the features of apoptosis in glioblastoma cells, and shows the relationship between regulatory RNAs and the apoptosis in tumor cells. In conclusion, potential target candidates are presented that are necessary for the development of new drugs for the treatment of glioblastoma.

Emerging role of lncRNAs in drug resistance mechanisms in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) originates in the squamous cell lining the mucosal surfaces of the head and neck region, including the oral cavity, nasopharynx, tonsils, oropharynx, larynx, and hypopharynx. The heterogeneity, anatomical, and functional characteristics of the patient make the HNSCC a complex and difficult-to-treat disease, leading to a poor survival rate and a decreased quality of life due to the loss of important physiologic functions and aggressive surgical injury. Alteration of driver-oncogenic and tumor-suppressing lncRNAs has recently been recently in HNSCC to obtain possible biomarkers for diagnostic, prognostic, and therapeutic approaches. This review provides current knowledge about the implication of lncRNAs in drug resistance mechanisms in HNSCC. Chemotherapy resistance is a major therapeutic challenge in HNSCC in which lncRNAs are implicated. Lately, it has been shown that lncRNAs involved in autophagy induced by chemotherapy and epithelial–mesenchymal transition (EMT) can act as mechanisms of resistance to anticancer drugs. Conversely, lncRNAs involved in mesenchymal–epithelial transition (MET) are related to chemosensitivity and inhibition of invasiveness of drug-resistant cells. In this regard, long non-coding RNAs (lncRNAs) play a pivotal role in both processes and are important for cancer detection, progression, diagnosis, therapy response, and prognostic values. As the involvement of more lncRNAs is elucidated in chemoresistance mechanisms, an improvement in diagnostic and prognostic tools could promote an advance in targeted and specific therapies in precision oncology.

The antitumour activity of C21 steroidal glycosides and their derivatives of Baishouwu: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Baishouwu has been used in China for thousands of years since it was first discovered in the late Tang Dynasty and flourished in the Song and Ming Dynasties. The Chinese herbal medicines named Baishouwu include Cynanchum auriculatum Royle ex Wight., Cynanchum bungei Decne. and Cynanchum wilfordii Hemsl. It is described in the Sign of Materia Medica as "sweet, bitter, reinforce liver and kidney, and non-toxic". It is widely used for nourishing the blood to expel wind, reinforcing liver and kidney, strengthening bones and muscles.

AIM OF THE REVIEW

In this review, the current research status of the C₂₁ steroidal glycosides and their derivatives of Baishouwu for malignant tumours and their anti-tumour mechanisms are discussed. This may lay the ground for potential application of Baishouwu and its active ingredients in the treatment of tumours.

MATERIALS AND METHODS

Scientific databases, including PubMed, Elsevier, Science Direct, Google Scholar, CNKI, WANFANG DATA and VIP were searched to gather data about Baishouwu and its C₂₁ steroidal glycosides and their derivatives.

RESULTS

Prior literature indicates that Baishouwu has important biological activities such as anti-tumour, anti-epileptic, reducing cholesterol, protection of liver and kidney and immunomodulatory, which are of increasing interest, especially its anti-tumour activity. Recent studies demonstrate that the C₂₁ steroidal glycosides of Baishouwu, which have prominent antitumour efficacy, are one of its main active ingredients. Presently, a variety of C₂₁ steroidal glycosides have been isolated from Baishouwu medicinal part, the tuberous root. This review summarizes the various antitumour activities of the C₂₁ steroidal glycosides and their derivatives of Baishouwu.

CONCLUSIONS

In this review, the antitumour effects and mechanisms of total C₂₁ steroidal glycosides and monomers and derivatives of Baishouwu in vitro and in vivo were summarized. Baishouwu can inhibit tumourigenesis by blocking tumour cell cycle progression, regulating numerous signaling pathways, promoting apoptosis, inhibiting tumour cells proliferation and metastasis, improving immunity and so on. This review provides a theoretical basis for inheriting and developing the medical heritage of the motherland, exploring the resources of traditional Chinese medicine for ethnic minorities and clinical rational drug use.

Long Non-coding RNA HOTAIR in Central Nervous System Disorders: New Insights in Pathogenesis, Diagnosis, and Therapeutic Potential

Central nervous system (CNS) disorders, such as ischemic stroke, neurodegenerative diseases, multiple sclerosis, traumatic brain injury, and corresponding neuropathological changes, often lead to death or long-term disability. Long non-coding RNA (lncRNA) is a class of non-coding RNA with a transcription length over 200 nt and transcriptional regulation. lncRNA is extensively involved in physiological and pathological processes through epigenetic, transcription, and post-transcriptional regulation. Further, dysregulated lncRNA is closely related to the occurrence and development of human diseases, including CNS disorders. HOX Transcript antisense RNA (HOTAIR) is the first discovered lncRNA with trans-transcriptional regulation. Recent studies have shown that HOTAIR may participate in the regulation of the occurrence and development of CNS disorders. In addition, HOTAIR has the potential to become a new biomarker for the diagnosis and prognosis assessment of CNS disorders and even provide a new therapeutic target for CNS disorders. Here, we reviewed the research results of HOTAIR in CNS disorders to provide new insights into the pathogenesis, diagnostic value, and therapeutic target potential of HOTAIR in human CNS disorders.

Prognostic utility of lncRNAs (LINC00565 and LINC00641) as molecular markers in glioblastoma multiforme (GBM)

Background and aim

Glioblastoma multiforme (GBM) is primary brain tumor grade IV characterized by fast cell proliferation, high mortality and morbidity and most lethal gliomas. Molecular approaches underlying its pathogenesis and progression with diagnostic and prognostic value have been an area of interest. Long-non coding RNAs (lncRNAs) aberrantly expressed in GBM have been recently studied. The aim is to investigate the clinical role of lncRNA565 and lncRNA641 in GBM patients.

Patients and methods

Blood samples were withdrawn from 35 newly diagnosed GBM cases with 15 healthy individuals, then lncRNA565 and lncRNA641 expression were evaluated using real time-PCR. Their diagnostic efficacy was detected using receiver operating characteristic curve. Progression free survival (PFS) and overall survival (OS) were studied using Kaplan–Meier curves.

Results

lncRNAs expressions were increased significantly among GBM as compared to control group. Their expressions were correlated with clinico-pathological data and survival pattern for the studied GBM patients. Higher levels of both lncRNAs were correlated to worse performance status. Expression of lncRNA565 was increased with large tumor size (≥ 5 cm). Survival analysis showed that both investigated lncRNA were increased with worse PFS and OS.

Conclusion

Expression of lncRNA565 and lncRNA641 in a liquid biopsy sample can be used as prognostic biomarker for GBM patients.

LncRNA HOTAIR sponges miR-301a-3p to promote glioblastoma proliferation and invasion through upregulating FOSL1

Glioblastoma, one of the most fatal brain tumors, is associated with a dismal prognosis and an extremely short overall survival. We previously reported that the overexpressed transient receptor potential channel TRPM7 is an essential glioblastoma regulator. Accumulating evidence suggests that long noncoding RNAs (lncRNAs) play an important role in glioma's initiation and progression. However, the function of lncRNA, HOX transcript antisense intergenic RNA (HOTAIR) mediated by TRPM7 in glioma remains unclear. In this study, HOTAIR expression was found to be positively regulated by TRPM7, significantly upregulated in glioma tissues, and is a poor prognosis factor for glioma patients. Moreover, reduced HOTAIR expression impeded the proliferation and invasion of glioma cells. Mechanistically, HOTAIR directly interacted with miR-301a-3p, and downregulation of miR-301a-3p efficiently reversed FOSL1 suppression induced by siRNA HOTAIR, which implied that HOTAIR positively regulated FOSL1 level through sponging miR-301a-3p and played an oncogenic role in glioma progression. In contrast to HOTAIR's role, miR-301a-3p alone served as a tumor suppressor to decrease glioma cell viability and migration/invasion. In agreement with HOTAIR's role, FOSL1 functioned as a tumorigenic gene in glioma pathogenesis, which was highly expressed in glioma tissues, and was shown to be an unfavorable prognostic factor for glioma patients. Mechanically, FOSL1 inhibition by siRNA FOSL1 efficiently rescued the oncogenic-like phenotypes caused by the miR-301a-3p inhibitor in glioma pathogenesis. SIGNIFICANCE: Our study elucidated the role of TRPM7-mediated HOTAIR as a miRNA sponge to target downstream FOSL1 oncogene and therefore consequently contribute to gliomagenesis, which shed new light on TRPM7/lncRNA-directed diagnostic and therapeutic approach in glioma.

The Involvement of Long Non-Coding RNAs in Glioma: From Early Detection to Immunotherapy

Glioma is a brain tumor that arises in the central nervous system and is categorized according to histology and molecular genetic characteristics. Long non-coding RNAs (lncRNAs) are RNAs longer than 200 nucleotides in length. They have been reported to influence significant events such as carcinogenesis, progression, and increased treatment resistance on glioma cells. Long non-coding RNAs promote cell proliferation, migration, epithelial-to-mesenchymal transition and invasion in glioma cells. Various significant advancements in transcriptomic profiling studies have enabled the identification of immune-related long non-coding RNAs as immune cell-specific gene expression regulators that mediates both stimulatory and suppressive immune responses, implying lncRNAs as potential candidates for improving immunotherapy efficacy against tumors and due to the lack of different diagnostic and treatments for glioma, lncRNAs are potential candidates to be used as future diagnostic, prognostic biomarker and treatment tools for glioma. This review’s primary purpose is to concentrate on the role of long non-coding RNAs in early glioma identification, treatment, and immunotherapy.

An Unanticipated Modulation of Cyclin-Dependent Kinase Inhibitors: The Role of Long Non-Coding RNAs

It is now definitively established that a large part of the human genome is transcribed. However, only a scarce percentage of the transcriptome (about 1.2%) consists of RNAs that are translated into proteins, while the large majority of transcripts include a variety of RNA families with different dimensions and functions. Within this heterogeneous RNA world, a significant fraction consists of sequences with a length of more than 200 bases that form the so-called long non-coding RNA family. The functions of long non-coding RNAs range from the regulation of gene transcription to the changes in DNA topology and nucleosome modification and structural organization, to paraspeckle formation and cellular organelles maturation. This review is focused on the role of long non-coding RNAs as regulators of cyclin-dependent kinase inhibitors’ (CDKIs) levels and activities. Cyclin-dependent kinases are enzymes necessary for the tuned progression of the cell division cycle. The control of their activity takes place at various levels. Among these, interaction with CDKIs is a vital mechanism. Through CDKI modulation, long non-coding RNAs implement control over cellular physiology and are associated with numerous pathologies. However, although there are robust data in the literature, the role of long non-coding RNAs in the modulation of CDKIs appears to still be underestimated, as well as their importance in cell proliferation control.

HOTTIP Mediated Therapy Resistance in Glioma Cells Involves Regulation of EMT-Related miR-10b

The advanced grade glioblastomas are characterized by dismal five-year survival rates and are associated with worse outcomes. Additionally, resistance to therapies is an additional burden responsible for glioma associated mortality. We studied the resistance against temozolomide (TMZ) as a surrogate to understand the mechanism of therapy resistance in glioma cancer cells. Screening of three glioma cells lines, A172, LN229 and SF268 revealed that SF268 glioma cells were particularly resistant to TMZ with the IC-50 of this cell line for TMZ ten times higher than for the other two cell lines. A role of lncRNAs in glioma progression has been identified in recent years and, therefore, we focused on lncRNAs for their role in regulating TMZ resistance in glioma cancer cells. lncRNA HOTTIP was found to be particularly elevated in SF268 cells and over-expression of HOTTIP in both A172 and LN229 remarkably increased their TMZ IC-50s, along with increased cell proliferation, migration, clonogenicity and markers of angiogenesis and metastasis. As a mechanism we observed increased expression of miRNA-10b and mesenchymal markers Zeb1/Zeb2 and reduced expression of E-cadherin in SF268 cells indicating a role of EMT in TMZ resistance. A172 and LN229 cells with overexpressed HOTTIP also had similarly induced EMT and the elevated miR-10b levels. Further, silencing of miR-10b in HOTTIP overexpressing cells as well as the SF268 cells reversed EMT with associated sensitization of all the tested cells to TMZ. Our results thus present a case for HOTTIP in native as well as acquired resistance of glioma cells against chemotherapy, with a key mechanistic role of EMT and the miR-10b. Thus, HOTTIP as well as miR-10b are critical targets for glioma therapy, and need to be tested further.

Effect of lncRNA MALAT1 on the Granulosa Cell Proliferation and Pregnancy Outcome in Patients With PCOS

Follicle arrest is one of the main characteristics of polycystic ovary syndrome (PCOS), the most common endocrinological disorder in reproductive-aged women. Increasing evidence proves that high anti-Mullerian hormone (AMH) levels may play an important role in follicular development. Long noncoding RNA (lncRNA) with a length of more than 200 nt is widely involved in the directional differentiation, growth, and development of cells, whereas whether lncRNA is involved in AMH's role in follicular development is unknown. In this study, we analyzed lncRNA expression in ovarian granulosa cells (GCs) collected from women with and without PCOS via high-throughput sequencing. The results showed that a total of 79 noncoding transcripts were differently expressed in GCs of PCOS patients, including upregulated lncRNA MALAT1. The upregulation of MALAT1 was further confirmed by RT-qPCR in GCs from a larger cohort of PCOS patients. Furthermore, knockdown MALAT1 can promote the proliferation of KGN cell in vitro. These data suggested a role for MALAT1 in the development of PCOS. Meanwhile, MALAT1 and phosphorylated SMAD 1/5 (Ser463/465) protein were upregulated in KGN cells after exogenous AMH stimulation, which identified AMH perhaps as a regulator for the expression of MALAT1. We also found that MALAT1 can predict clinical pregnancy outcome to a certain extent by ROC curve analysis (area: 0.771, p = 0.007, 95% CI: 0.617-0.925, sensitivity: 57.1%, specificity: 91.7%). Thus, our findings revealed a role of lncRNA MALAT1 in inhibiting granulosa cell proliferation and may be correlated with pregnancy outcome in PCOS.

Molecular Features of Glioma Determined and Validated Using Combined TCGA and GTEx Data Analyses

Gliomas are among the most common intracranial tumors which originated from neuroepithelial cells. Increasing evidence has revealed that long noncoding RNA (lncRNA)-microRNA (miRNA)-mRNA module regulation and tumor-infiltrating immune cells play important regulatory roles in the occurrence and progression of gliomas. However, the precise underlying molecular mechanisms remain largely unknown. Data on gliomas in The Cancer Genome Atlas lack normal control samples; to overcome this limitation, we combined 665 The Cancer Genome Atlas glioma RNA sequence datasets with 188 Genotype-Tissue Expression normal brain RNA sequences to construct an expression matrix profile after normalization. We systematically analyzed the expression of mRNAs, lncRNAs, and miRNAs between gliomas and normal brain tissues. Kaplan–Meier survival analyses were conducted to screen differentially expressed mRNAs, lncRNAs, and miRNAs. A prognostic miRNA-related competitive endogenous RNA network was constructed, and the core subnetworks were filtered using 6 miRNAs, 3 lncRNAs, and 11 mRNAs. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed to investigate the biological functions of significantly dysregulated mRNAs. Co-expression network analysis was performed to analyze and screen the core genes. Furthermore, single-sample Gene Set Enrichment Analysis and immune checkpoint gene expression analysis were performed, as co-expression analysis indicated immune gene dysregulation in glioma. Finally, the expression of representative dysregulated genes was validated in U87 cells at the transcriptional level, establishing a foundation for further research. We identified 7017 mRNAs, 437 lncRNAs, and 9 miRNAs that were differentially expressed in gliomas. Kaplan–Meier survival analysis revealed 5684 mRNAs, 61 lncRNAs, and 7 miRNAs with potential as prognostic signatures in patients with glioma. The hub subnetwork of the competing endogenous RNA network between PART1-hsa-mir-25-SLC12A5/TACC2/BSN/TLN2/ZDHHC8 was screened out. Gene co-expression network, single-sample Gene Set Enrichment Analysis, and immune checkpoint expression analysis demonstrated that tumor-infiltrating immune cells are closely related to gliomas. We identified novel potential biomarkers to predict survival and therapeutic targets for patients with gliomas based on a large-scale sample. Importantly, we filtered pivotal genes that provide valuable information for further exploration of the molecular mechanisms underlying glioma tumorigenesis and progression.