Exosome-Mediated Transfer of Long Noncoding RNA HOTAIR Regulates Temozolomide Resistance by miR-519a-3p/RRM1 Axis in Glioblastoma

Extracellular Vesicles as Mediators and Potential Targets in Combating Cancer Drug Resistance

Extracellular vesicles (EVs) are key mediators in the communication between cancer cells and their microenvironment, significantly influencing drug resistance. This review provides a comprehensive analysis of the roles of EVs in promoting drug resistance through mechanisms such as drug efflux, apoptosis resistance, autophagy imbalance, and tumor microenvironment modulation. Despite extensive research, details of EVs biogenesis, cargo selection, and specific pathways in EVs-mediated drug resistance are not fully understood. This review critically examines recent advancements, highlighting key studies that elucidate the molecular mechanisms of EVs functions. Additionally, innovative therapeutic strategies targeting EVs are explored, including inhibiting EVs biogenesis, engineering EVs for drug delivery, and identifying resistance-inhibiting molecules within EVs. By integrating insights from primary research and proposing new directions for future studies, this review aims to advance the understanding of EVs in cancer biology and foster effective interventions to mitigate drug resistance in cancer therapy.

HOTAIR in cancer: diagnostic, prognostic, and therapeutic perspectives

The long non-coding RNA HOTAIR is overexpressed in many cancers and is associated with several cancer-promoting effects, including increased cell proliferation, migration and treatment resistance. HOTAIR levels correlate with tumor stage, lymph node metastasis and overall survival in patients with various types of cancer. This highlights the potential uses of HOTAIR, including early cancer detection, predicting patient outcome, identifying high-risk individuals and assisting in therapy selection and monitoring. The aim of this review is to provide a comprehensive summary of the research progress, molecular mechanisms and clinical significance of HOTAIR in various human cancers. In addition, the clinical applications of HOTAIR, such as targeted therapy, radiotherapy, chemotherapy and immunotherapy, are discussed, and relevant information on the potential future advances of HOTAIR in cancer research is provided.

Roles of HOTAIR Long Non-coding RNA in Gliomas and Other CNS Disorders

HOX transcript antisense intergenic RNA (HOTAIR) is a long non-coding RNA (lncRNA) which is increasingly being perceived as a tremendous molecular mediator of brain pathophysiology at multiple levels. Epigenetic regulation of target gene expression carried out by HOTAIR is thorough modulation of chromatin modifiers; histone methyltransferase polycomb repressive complex 2 (PRC2) and histone demethylase lysine-specific demethylase 1 (LSD1). Incidentally, HOTAIR was the first lncRNA shown to elicit sponging of specific microRNA (miRNA or miR) species in a trans-acting manner. It has been extensively studied in various cancers, including gliomas and is regarded as a prominent pro-tumorigenic and pro-oncogenic lncRNA. Indeed, the expression of HOTAIR may serve as glioma grade predictor and prognostic biomarker. The objective of this timely review is not only to outline the multifaceted pathogenic roles of HOTAIR in the development and pathophysiology of gliomas and brain cancers, but also to delineate the research findings implicating it as a critical regulator of overall brain pathophysiology. While the major focus is on neuro-oncology, wherein HOTAIR represents a particularly potent underlying pathogenic player and a suitable therapeutic target, mechanisms underlying the regulatory actions of HOTAIR in neurodegeneration, traumatic, hypoxic and ischemic brain injuries, and neuropsychiatric disorders are also presented.

Tumorigenic and tumoricidal properties of exosomes in cancers; a forward look

In recent decades, emerging data have highlighted the critical role of extracellular vesicles (EVs), especially (exosomes) Exos, in the progression and development of several cancer types. These nano-sized vesicles are released by different cell lineages within the cancer niche and maintain a suitable platform for the interchange of various signaling molecules in a paracrine manner. Based on several studies, Exos can transfer oncogenic factors to other cells, and alter the activity of immune cells, and tumor microenvironment, leading to the expansion of tumor cells and metastasis to the remote sites. It has been indicated that the cell-to-cell crosstalk is so complicated and a wide array of factors are involved in this process. How and by which mechanisms Exos can regulate the behavior of tumor cells and non-cancer cells is at the center of debate. Here, we scrutinize the molecular mechanisms involved in the oncogenic behavior of Exos released by different cell lineages of tumor parenchyma. Besides, tumoricidal properties of Exos from various stem cell (SC) types are discussed in detail.

Unveiling the functional paradigm of exosome-derived long non-coding RNAs (lncRNAs) in cancer: based on a narrative review and systematic review

BACKGROUND AND PURPOSE

The intricate mechanisms underlying intercellular communication within the tumor microenvironment remain largely elusive. Recently, attention has shifted towards exploring the intercellular signaling mediated by exosomal long non-coding RNAs (lncRNAs) within this context. This comprehensive systematic review aims to elucidate the functional paradigm of exosome-derived lncRNAs in cancer.

MATERIALS AND METHODS

The review provides a comprehensive narrative of lncRNA definition, characteristics, as well as the formation, sorting, and uptake processes of exosome-derived lncRNAs. Additionally, it describes comprehensive technology for exosome research and nucleic acid drug loading. This review further systematically examines the cellular origins, functional roles, and underlying mechanisms of exosome-derived lncRNAs in recipient cells within the cancer setting.

RESULTS

The functional paradigm of exosome-derived lncRNAs in cancer mainly depends on the source cells and sorting mechanism of exosomal lncRNAs, the recipient cells and uptake mechanisms of exosomal lncRNAs, and the specific molecular mechanisms of lncRNAs in recipient cells. The source cells of exosomal lncRNAs mainly involved in the current review included tumor cells, cancer stem cells, normal cells, macrophages, and cancer-associated fibroblasts.

CONCLUSION

This synthesis of knowledge offers valuable insights for accurately identifying exosomal lncRNAs with potential as tumor biomarkers. Moreover, it aids in the selection of appropriate targeting strategies and preclinical models, thereby facilitating the clinical translation of exosomal lncRNAs as promising therapeutic targets against cancer. Through a comprehensive understanding of the functional role of exosome-derived lncRNAs in cancer, this review paves the way for advancements in personalized medicine and improved treatment outcomes.

Advances on Liquid Biopsy Analysis for Glioma Diagnosis

Gliomas comprise the most frequent primary central nervous system (CNS) tumors, characterized by remarkable genetic and epigenetic heterogeneity, difficulty in monitoring, and increased relapse and mortality rates. Tissue biopsy is an established method of tumor cell collection and analysis that enables diagnosis, classification of different tumor types, and prediction of prognosis upon confirmation of tumor's location for surgical removal. However, it is an invasive and often challenging procedure that cannot be used for frequent patient screening, detection of mutations, disease monitoring, or resistance to therapy. To this end, the minimally invasive procedure of liquid biopsy has emerged, allowing effortless tumor sampling and enabling continuous monitoring. It is considered a novel preferable way to obtain faster data on potential tumor risk, personalized diagnosis, prognosis, and recurrence evaluation. The purpose of this review is to describe the advances on liquid biopsy for glioma diagnosis and management, indicating several biomarkers that can be utilized to analyze tumor characteristics, such as cell-free DNA (cfDNA), cell-free RNA (cfRNA), circulating proteins, circulating tumor cells (CTCs), and exosomes. It further addresses the benefit of combining liquid biopsy with radiogenomics to facilitate early and accurate diagnoses, enable precise prognostic assessments, and facilitate real-time disease monitoring, aiming towards more optimal treatment decisions.

Exosomal miR-181a-5p derived from SAOS-2 cells promotes macrophages M2 polarization by targeting RORA

Although the interaction between tumor cells and tumor-associated macrophages (TAMs) has been widely studied; however, the mechanism of osteosarcoma cells in regulating the polarization of TAMs remains unclear. Exosomes from SAOS-2 cells were isolated and validated by electron microscopy and Western blot. Transfection of indicated plasmids was applied to modify the expressions of miR-181a-5p and RAR-related orphan receptor alpha (RORA). Flow cytometric analysis was carried out to analyze M1/M2 macrophage polarization. Quantitative real-time PCR was performed to determine the levels of miR-181a-5p and RORA. Protein levels of CD63, CD81, RORA, CD163, CD206, IL-10, CXCL10, and IL-1β were evaluated by Western blot. The direct interaction of miR-181a-5p and RORA was validated by dual-luciferase activity assay. The expression of miR-181a-5p was upregulated in osteosarcoma tissues and presented in SAOS-2-derived exosomes. SAOS-2-derived exosomes promoted the polarization of M2 macrophages by transferring miR-181a-5p. In addition, RORA was downregulated in osteosarcoma tissues and showed a negative correlation with miR-181a-5p. RORA was found to be the downstream target of miR-181a-5p in SAOS-2 cells. Inhibition of RORA reversed the effects of miR-181a-5p knockdown on the polarization of M2 macrophages. The results showed that exosomal miR-181a-5p derived from osteosarcoma cells induced polarization of M2 macrophages via targeting RORA.

New perspectives in liquid biopsy for glioma patients

PURPOSE OF REVIEW

Gliomas are the most common primary tumors of the central nervous system. They are characterized by a disappointing prognosis and ineffective therapy that has shown no substantial improvements in the past 20 years. The lack of progress in treating gliomas is linked with the inadequacy of suitable tumor samples to plan translational studies and support laboratory developments. To overcome the use of tumor tissue, this commentary review aims to highlight the potential for the clinical application of liquid biopsy (intended as the study of circulating biomarkers in the blood), focusing on circulating tumor cells, circulating DNA and circulating noncoding RNA.

RECENT FINDINGS

Thanks to the increasing sensitivity of sequencing techniques, it is now possible to analyze circulating nucleic acids and tumor cells (liquid biopsy).

SUMMARY

Although studies on the use of liquid biopsy are still at an early stage, the potential clinical applications of liquid biopsy in the study of primary brain cancer are many and have the potential to revolutionize the approach to neuro-oncology, and importantly, they offer the possibility of gathering information on the disease at any time during its history.

Extracellular vesicles and particles impact the systemic landscape of cancer

Intercellular cross talk between cancer cells and stromal and immune cells is essential for tumor progression and metastasis. Extracellular vesicles and particles (EVPs) are a heterogeneous class of secreted messengers that carry bioactive molecules and that have been shown to be crucial for this cell-cell communication. Here, we highlight the multifaceted roles of EVPs in cancer. Functionally, transfer of EVP cargo between cells influences tumor cell growth and invasion, alters immune cell composition and function, and contributes to stromal cell activation. These EVP-mediated changes impact local tumor progression, foster cultivation of pre-metastatic niches at distant organ-specific sites, and mediate systemic effects of cancer. Furthermore, we discuss how exploiting the highly selective enrichment of molecules within EVPs has profound implications for advancing diagnostic and prognostic biomarker development and for improving therapy delivery in cancer patients. Altogether, these investigations into the role of EVPs in cancer have led to discoveries that hold great promise for improving cancer patient care and outcome.

Functions and underlying mechanisms of lncRNA HOTAIR in cancer chemotherapy resistance

Chemotherapy has been one of the most important treatments for advanced cancer in recent decades. Although the sensitivity rate of initial chemotherapy is high, patients with chemotherapy resistant tumors, experience tumor recurrence. In recent years, many studies have shown that homeobox transcript antisense intergenic RNA (HOTAIR) is involved in many pathological processes including carcinogenesis. The abnormal regulation of a variety of cell functions by HOTAIR, such as apoptosis, the cell cycle, epithelial-mesenchymal transition, autophagy, self-renewal, and metabolism, is associated with chemotherapy resistance. Therefore, there is an urgent need to understand the biology and mechanism underlying the role of HOTAIR in tumor behavior and its potential as a biomarker for predicting the effect of chemotherapy. In this manuscript, we review the mechanisms underlying HOTAIR-related drug resistance and discuss the limitations of current knowledge and propose potential future directions.

Molecular and Circulating Biomarkers in Patients with Glioblastoma

Glioblastoma is the most aggressive malignant tumor of the central nervous system with a low survival rate. The difficulty of obtaining this tumor material represents a major limitation, making the real-time monitoring of tumor progression difficult, especially in the events of recurrence or resistance to treatment. The identification of characteristic biomarkers is indispensable for an accurate diagnosis, the rigorous follow-up of patients, and the development of new personalized treatments. Liquid biopsy, as a minimally invasive procedure, holds promise in this regard. The purpose of this paper is to summarize the current literature regarding the identification of molecular and circulating glioblastoma biomarkers and the importance of their integration as a valuable tool to improve patient care.

Examples of Inverse Comorbidity between Cancer and Neurodegenerative Diseases: A Possible Role for Noncoding RNA

Cancer is one of the most common causes of death; in parallel, the incidence and prevalence of central nervous system diseases are equally high. Among neurodegenerative diseases, Alzheimer’s dementia is the most common, while Parkinson’s disease (PD) is the second most frequent neurodegenerative disease. There is a significant amount of evidence on the complex biological connection between cancer and neurodegeneration. Noncoding RNAs (ncRNAs) are defined as transcribed nucleotides that perform a variety of regulatory functions. The mechanisms by which ncRNAs exert their functions are numerous and involve every aspect of cellular life. The same ncRNA can act in multiple ways, leading to different outcomes; in fact, a single ncRNA can participate in the pathogenesis of more than one disease—even if these seem very different, as cancer and neurodegenerative disorders are. The ncRNA activates specific pathways leading to one or the other clinical phenotype, sometimes with obvious mechanisms of inverse comorbidity. We aimed to collect from the existing literature examples of inverse comorbidity in which ncRNAs seem to play a key role. We also investigated the example of mir-519a-3p, and one of its target genes Poly (ADP-ribose) polymerase 1, for the inverse comorbidity mechanism between some cancers and PD. We believe it is very important to study the inverse comorbidity relationship between cancer and neurodegenerative diseases because it will help us to better assess these two major areas of human disease.

Serum-derived extracellular vesicles facilitate temozolomide resistance in glioblastoma through a HOTAIR-dependent mechanism

Extracellular vesicle (EV)-mediated transfer of long non-coding RNAs (lncRNAs) has been reported to regulate chemoresistance in various cancers. We herein investigate the therapeutic potential of bioinformatically identified HOTAIR transferred by serum-derived EVs (serum-EVs) in temozolomide (TMZ) resistance of glioblastoma (GBM) and the downstream mechanisms. EVs were isolated from the serum of GBM patients. Expression of HOTAIR was examined in the clinical tissue samples and serum-EVs of GBM patients. The downstream miRNAs of HOTAIR and its target genes were predicted in silico. The effects of the HOTAIR transmitted by serum-EVs in malignant phenotypes, tumor growth, and TMZ resistance were assessed in vitro and in vivo. HOTAIR expression was upregulated in clinical tissues, cells, and serum-EVs of GBM. Co-culture data showed that GBM-serum-EVs facilitated GBM cell proliferative and invasive phenotypes and TMZ resistance by elevating HOTAIR. In GBM cells, HOTAIR competitively bound to miR-526b-3p and weakened miR-526b-3p’s binding ability to EVA1, thus increasing the expression of EVA1. Furthermore, HOTAIR carried by serum-EVs promoted tumor growth and TMZ resistance in vivo by suppressing miR-526b-3p-mediated EVA1 inhibition. GBM-serum-EV-enclosed HOTAIR may augment GBM progression and chemoresistance through miR-526b-3p downregulation and EVA1 upregulation. These results provide a strategy to reduce TMZ resistance in GBM treatment.

Exosomal lncRNA HOTAIR Promotes the Progression and Angiogenesis of Endometriosis via the miR-761/HDAC1 Axis and Activation of STAT3-Mediated Inflammation

Background

Long non-coding RNA (lncRNA) and exosomes are implicated in endometriosis development. We measured the expression of an exosomal lncRNA, homeobox transcript antisense RNA (HOTAIR), and explored its molecular mechanism in endometriosis progression.

Methods

Expression of HOTAIR and microRNA (miR)-761 in different endometrial tissues was measured. Exosomes were isolated from a culture medium of endometrial stromal cells (ESCs). RT-qPCR was used to measure HOTAIR expression in different exosome types. CCK-8, Edu, wound healing, transwell assays, flow cytometry and tube formation were used to detect the role of exosomal HOTAIR on ESCs and human umbilical vein endothelial cells (HUVECs). The relationship among miR-761, HOTAIR, and histone deacetylase 1 (HDAC1) was verified by dual-luciferase reporter assay. ESCs were transfected with miR-761 mimics or HDAC1 small interfering RNA (si-RNA) to ascertain if alterations in expression of miR-761 or HDAC1 could reverse the effect of exosomal HOTAIR. Then, we detected the effect of the HOTAIR/miR-761/HDAC1 axis on signal transducer and activator of transcription 3 (STAT3)-mediated inflammation. In vivo experiments were conducted to verify in vitro results.

Results

HOTAIR expression was upregulated and miR-761 expression was downregulated in ectopic endometrium tissues. HOTAIR was packaged into exosomes and transported from ESCs to surrounding cells. Exosomal HOTAIR promoted the proliferation, migration, and invasion, and inhibited the apoptosis of ESCs. Angiogenesis of HUVECs was enhanced after cultured with exosomal HOTAIR. HOTAIR acted as a competing endogenous RNA to downregulate miR-761 and increase HDAC1 expression. miR-761 overexpression or HDAC1 knockdown reversed the role of exosomal HOTAIR on ESCs and HUVECs. The HOTAIR/miR-761/HDAC1 axis could activate STAT3-related proinflammatory cytokines and stattic (inhibitor of phosphorylated-STAT3) could reverse the effect of HOTAIR on ESCs and HUVECs. In vivo experiments suggested that exosomal HOTAIR promoted the growth of endometrial lesions in vivo.

Conclusion

Exosomal HOTAIR promoted the progression and angiogenesis of endometriosis by regulating the miR-761/HDAC1 axis and activating STAT3-mediated inflammation in vitro and in vivo, which may provide promising treatment for endometriosis.

Dynamic Intercell Communication between Glioblastoma and Microenvironment through Extracellular Vesicles

Glioblastoma is simultaneously the most common and most aggressive primary brain tumor in the central nervous system, with poor patient survival and scarce treatment options. Most primary glioblastomas reoccur and evolve radio- and chemoresistant properties which make them resistant to further treatments. Based on gene mutations and expression profiles, glioblastoma is relatively well classified; however, research shows that there is more to glioblastoma biology than that defined solely by its genetic component. Specifically, the overall malignancy of the tumor is also influenced by the dynamic communication to its immediate and distant environment, as important messengers to neighboring cells in the tumor microenvironment extracellular vesicles (EVs) have been identified. EVs and their cargo can modulate the immune microenvironment and other physiological processes, and can interact with the host immune system. They are involved in tumor cell survival and metabolism, tumor initiation, progression, and therapy resistance. However, on the other hand EVs are thought to become an effective treatment alternative, since they can cross the blood-brain barrier, are able of specific cell-targeting and can be loaded with various therapeutic molecules.

Current landscape of tumor-derived exosomal ncRNAs in glioma progression, detection, and drug resistance

Glioma is the most common and fatal tumor of the central nervous system in humans. Despite advances in surgery, radiotherapy, and chemotherapeutic agents, glioma still has a poor prognosis. The tumor microenvironment (TME) of glioma is of highly complex heterogeneity, which relies on a network-based communication between glioma cells and other stromal cell types. Exosomes are the most common type of naturally occurring extracellular vesicles, ranging in size from 40 to 160 nm, and can serve as carriers for proteins, RNAs, and other biologically active molecules. Recent evidence has shown that glioma-derived exosomes (GDEs) can be integrally detected in the local tissue and circulatory blood samples, and also can be transferred to recipient cells to mediate transmission of genetic information. Non-coding RNAs (ncRNAs) mainly including microRNA, long non-coding RNA, and circular RNA, account for a large portion of the human transcriptome. A broad range of ncRNAs encapsulated in GDEs is reported to exert regulatory functions in various pathophysiological processes of glioma. Herein, this review summarizes the latest findings on the fundamental roles of GDE ncRNAs that have been implicated in glioma behaviors, immunological regulation, diagnosis potential, and treatment resistance, as well as the current limitations and perspectives. Undoubtedly, a thorough understanding of this area will provide comprehensive insights into GDE-based clinical applications for combating gliomas.

Emodin inhibits the progression of acute pancreatitis via regulation of lncRNA TUG1 and exosomal lncRNA TUG1

Acute pancreatitis (AP) is one of the most frequent gastrointestinal diseases and has no specific treatment. It has been shown that dysfunction of pancreatic acinar cells can lead to AP progression. Emodin is a natural product, which can alleviate the symptoms of AP. However, the mechanism by which emodin regulates the function of pancreatic acinar cells remains unclear. Thus, the present study aimed to investigate the mechanism by which emodin modulates the function of pancreatic acinar cells. To mimic AP in vitro, pancreatic acinar cells were cotreated with caerulein and lipopolysaccharide (LPS). Exosomes were isolated using the ExoQuick precipitation kit. Western blot analysis, Nanosight Tracking analysis and transmission electron microscopy were performed to detect the efficiency of exosome separation. Gene expression was detected by reverse transcription‑quantitative PCR. The levels of IL‑1β and TNF‑α were detected by ELISA. The data indicated that emodin significantly decreased the levels of IL‑1β and TNF‑α in the supernatant samples derived from AR42J cells cotreated with caerulein and LPS. In addition, emodin significantly promoted the proliferation of AR42J cells cotreated with caerulein and LPS, and inhibited apoptosis, while the effect of emodin was reversed by long non‑coding (lnc)RNA taurine upregulated 1 (TUG1) overexpression. The expression level of TUG1 in AR42J cells or exosomes derived from AR42J cells was significantly increased following treatment of the cells with LPS and caerulein, while this effect was notably reversed by emodin treatment. In addition, exosomes derived from caerulein and LPS cotreated AR42J cells inhibited the differentiation and anti‑inflammatory function of regulatory T cells, while treatment of the cells with emodin significantly decreased this effect. In conclusion, the data indicated that emodin inhibited the induction of inflammation in AR42J cells by regulating the expression of cellular and exosomal lncRNA. Therefore, emodin may be used as a potential agent for the treatment of AP.

Exosomal transfer of miR‑25‑3p promotes the proliferation and temozolomide resistance of glioblastoma cells by targeting FBXW7

Intrinsic or acquired resistance to temozolomide (TMZ) is a frequent occurrence in patients with glioblastoma (GBM). Accumulating evidence has indicated that the exosomal transfer of proteins and RNAs may confer TMZ resistance to recipient cells; however, the potential molecular mechanisms are not fully understood. Thus, the aim of the present study was to elucidate the possible role of exosomal microRNAs (miRNAs/miRs) in the acquired resistance to TMZ in GBM. A TMZ-resistant GBM cell line (A172R) was used, and exosomes derived from A172R cells were extracted. Exosomal miR-25-3p was identified as a miRNA associated with TMZ resistance. The potential functions of exosomal miR-25-3p were evaluated by reverse transcription-quantitative PCR, as well as cell viability, colony formation and soft agar assay, flow cytometry, western blot analysis, BrdU incorporation assay, tumor xenograft formation, luciferase reporter assay and RNA immunoprecipitation. It was found that A172R-derived exosomes promoted the proliferation and TMZ resistance of sensitive GBM cells. Moreover, miR-25-3p epxression was upregulated in the exosomes of A172R cells and in serum samples of patients with GBM treated with TMZ. The depletion of exosomal miR-25-3p partially abrogated the effects induced by the transfer of exosomes from A172R cells. By contrast, miR-25-3p overexpression facilitated the proliferation and TMZ resistance of sensitive GBM cells. F-box and WD repeat domain-containing-7 (FBXW7) was identified as a direct target of miR-25-3p. FBXW7 knockdown promoted the proliferation and TMZ resistance of GBM cells. Furthermore, the exosomal transfer of miR-25-3p promoted c-Myc and cyclin E expression by downregulating FBXW7. Our results provided a novel insight into exosomal microRNAs in acquired TMZ resistance of GBM cells. Besides, exosomal miR-25-3p might be a potential prognostic marker for GBM patients.

Role of Long Non-Coding RNAs in Conferring Resistance in Tumors of the Nervous System

Tumors of the nervous system can be originated from several locations. They mostly have high mortality and morbidity rate. The emergence of resistance to chemotherapeutic agents is a hurdle in the treatment of patients. Long non-coding RNAs (lncRNAs) have been shown to influence the response of glioblastoma/glioma and neuroblastoma to chemotherapeutic agents. MALAT1, NEAT1, and H19 are among lncRNAs that affect the response of glioma/glioblastoma to chemotherapy. As well as that, NORAD, SNHG7, and SNHG16 have been shown to be involved in conferring this phenotype in neuroblastoma. Prior identification of expression amounts of certain lncRNAs would help in the better design of therapeutic regimens. In the current manuscript, we summarize the impact of lncRNAs on chemoresistance in glioma/glioblastoma and neuroblastoma.

LncRNA PlncRNA-1 accelerates the progression of prostate cancer by regulating PTEN/Akt axis

Long non-coding RNAs are key regulators of tumor development and progression, with the potential to be biomarkers of tumors. This study aimed to explore the role of PlncRNA-1 in the progression of prostate cancer (PCa). We found that PlncRNA-1 was up-regulated in 85.29% of PCa tissues and could predict the T stage of PCa patients to a certain extent. Results showed that inhibition of PlncRNA-1 expression potentially promoted cell apoptosis, suppressed the proliferation, migration, and invasion of cells, and triggered G2/M cycle arrest in vitro and in vivo. PlncRNA-1 was mainly localized in the nucleus and PlncRNA-1 expression and phosphatase and tensin homologue (PTEN) expression were negatively correlated. Mechanistically, knockdown of PlncRNA-1 increased expression levels of PTEN protein and phosphorylated PTEN protein, and decreased expression levels of Akt protein and phosphorylated Akt protein. Rescue experiments demonstrated that PTEN inhibitors abolished the changes in PTEN/Akt pathway caused by PlncRNA-1 interference. PlncRNA-1 can promote the occurrence and development of PCa via the PTEN/Akt pathway. PlncRNA-1 may, therefore, be a new candidate target for the treatment of PCa.

Critical role of HOX transcript antisense intergenic RNA (HOTAIR) in gliomas

Despite extensive research, gliomas are associated with high morbidity and mortality, mainly attributed to the rapid growth rate, excessive invasiveness, and molecular heterogeneity, as well as regenerative potential of cancer stem cells. Therefore, elucidation of the underlying molecular mechanisms and the identification of potential molecular diagnostic and prognostic biomarkers are of paramount importance. HOX transcript antisense intergenic RNA (HOTAIR) is a well-studied long noncoding RNA, playing an emerging role in tumorigenesis of several human cancers. A growing amount of preclinical and clinical evidence highlights the pro-oncogenic role of HOTAIR in gliomas, mainly attributed to the enhancement of proliferation and migration, as well as inhibition of apoptosis. In vitro and in vivo studies demonstrate that HOTAIR modulates the activity of specific transcription factors, such as MXI1, E2F1, ATF5, and ASCL1, and regulates the expression of cell cycle-associated genes along with related signaling pathways, like the Wnt/β-catenin axis. Moreover, it can interact with specific miRNAs, including miR-326, miR-141, miR-148b-3p, miR-15b, and miR-126-5p. Of importance, HOTAIR has been demonstrated to enhance angiogenesis and affect the permeability of the blood-tumor barrier, thus modulating the efficacy of chemotherapeutic agents. Herein, we provide evidence on the functional role of HOTAIR in gliomas and discuss the benefits of its targeting as a novel approach toward glioma treatment.