Long noncoding RNA TPT1-AS1 downregulates the microRNA-770-5p expression to inhibit glioma cell autophagy and promote proliferation through STMN1 upregulation

Regulation of autophagy by non-coding RNAs in human glioblastoma

Glioblastoma, a lethal form of brain cancer, poses substantial challenges in treatment due to its aggressive nature and resistance to standard therapies like radiation and chemotherapy. Autophagy has a crucial role in glioblastoma progression by supporting cellular homeostasis and promoting survival under stressful conditions. Non-coding RNAs (ncRNAs) play diverse biological roles including, gene regulation, chromatin remodeling, and the maintenance of cellular homeostasis. Emerging evidence reveals the intricate regulatory mechanisms of autophagy orchestrated by non-coding RNAs (ncRNAs) in glioblastoma. The diverse roles of these ncRNAs in regulating crucial autophagy-related pathways, including AMPK/mTOR signaling, the PI3K/AKT pathway, Beclin1, and other autophagy-triggering system regulation, sheds light on ncRNAs biological mechanisms in the proliferation, invasion, and therapy response of glioblastoma cells. Furthermore, the clinical implications of targeting ncRNA-regulated autophagy as a promising therapeutic strategy for glioblastoma treatment are in the spotlight of ongoing studies. In this review, we delve into our current understanding of how ncRNAs regulate autophagy in glioblastoma, with a specific focus on microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), and their intricate interplay with therapy response.

Dual perspective on autophagy in glioma: Detangling the dichotomous mechanisms of signaling pathways for therapeutic insights

Autophagy is a normal physiological process that aids the recycling of cellular nutrients, assisting the cells to cope with stressed conditions. However, autophagy's effect on cancer, including glioma, is uncertain and involves complicated molecular mechanisms. Several contradictory reports indicate that autophagy may promote or suppress glioma growth and progression. Autophagy inhibitors potentiate the efficacy of chemotherapy or radiation therapy in glioma. Numerous compounds stimulate autophagy to cause glioma cell death. Autophagy is also involved in the therapeutic resistance of glioma. This review article aims to detangle the complicated molecular mechanism of autophagy to provide a better perception of the two-sided role of autophagy in glioma and its therapeutic implications. The protein and epigenetic modulators of the cytoprotective and cytotoxic role of autophagy are described in this article. Moreover, several signaling pathways are associated with autophagy and its effects on glioma. We have reviewed the molecular pathways and highlighted the signaling axis involved in cytoprotective and cytotoxic autophagy. Additionally, this article discusses the role of autophagy in therapeutic resistance, including glioma stem cell maintenance and tumor microenvironment regulation. It also summarizes several investigations on the anti-glioma effects of autophagy modulators to understand the associated mechanisms and provide insights regarding its therapeutic implications.

Long non-coding RNA TPT1-AS1 inhibits ferroptosis in ovarian cancer by regulating GPX4 via CREB1 regulation

BACKGROUND

Long non-coding RNAs (lncRNAs) play crucial roles in cellular processes, with dysregulation implicated in various diseases, including cancers. The lncRNA TPT1-AS1 (TPT1 Antisense RNA 1) promotes tumor progression in several cancers, including ovarian cancer (OC), but its influence on ferroptosis and interaction with other proteins remains underexplored.

METHODS

In this study, we employed a multi-faceted approach to investigate the functional significance of TPT1-AS1 in OC. We assessed TPT1-AS1 expression in OC specimens and cell lines using RT-qPCR, in situ hybridization (ISH), and fluorescence in situ hybridization (FISH) assays. Functional assays included evaluating the impact of TPT1-AS1 knockdown on OC cell proliferation, migration, invasiveness, and cell cycle progression. Further, we explored and validated the interaction of TPT1-AS1 with other proteins using bioinformatics. Finally, we investigated TPT1-AS1 involvement in erastin-induced ferroptosis using Iron Assay, Malondialdehyde (MDA) assay, and reactive oxygen species (ROS) detection.

RESULTS

Our findings revealed that TPT1-AS1 overexpression in OC correlated with an unfavorable prognosis. TPT1-AS1 knockdown suppressed cell proliferation, migration, and invasiveness. Additionally, TPT1-AS1 inhibited erastin-induced ferroptosis, and in vivo experiments confirmed its oncogenic impact on tumor development. Mechanistically, TPT1-AS1 was found to regulate Glutathione Peroxidase 4 (GPX4) transcription via CREB1 (cAMP response element-binding protein 1) and interact with RNA-binding protein (RBP) KHDRBS3 (KH RNA Binding Domain Containing, Signal Transduction Associated 3) to regulate CREB1.

CONCLUSION

TPT1-AS1 promotes OC progression by inhibiting ferroptosis and upregulating CREB1, forming a regulatory axis with KHDRBS3. These findings highlight the regulatory network involving lncRNAs, RBPs, and transcription factors in cancer progression.

Long non-coding RNAs; potential contributors in cancer chemoresistance through modulating diverse molecular mechanisms and signaling pathways

One of the mainstays of cancer treatment is chemotherapy. Drug resistance, however, continues to be the primary factor behind clinical treatment failure. Gene expression is regulated by long non-coding RNAs (lncRNAs) in several ways, including chromatin remodeling, translation, epigenetic, and transcriptional levels. Cancer hallmarks such as DNA damage, metastasis, immunological evasion, cell stemness, drug resistance, metabolic reprogramming, and angiogenesis are all influenced by LncRNAs. Numerous studies have been conducted on LncRNA-driven mechanisms of resistance to different antineoplastic drugs. Diverse medication kinds elicit diverse resistance mechanisms, and each mechanism may have multiple contributing factors. As a result, several lncRNAs have been identified as new biomarkers and therapeutic targets for identifying and managing cancers. This compels us to thoroughly outline the crucial roles that lncRNAs play in drug resistance. In this regard, this article provides an in-depth analysis of the recently discovered functions of lncRNAs in the pathogenesis and chemoresistance of cancer. As a result, the current research might offer a substantial foundation for future drug resistance-conquering strategies that target lncRNAs in cancer therapies.

SP2-induced circPUM1 modulates chemoresistance and nature killer cell toxicity in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a type of tumour found in the cavity that is characterized by differentiation and metastasis to the lymph nodes. Although diagnosis strategy and clinical treatment have recently improved, the outcomes for OSCC patients remain unsatisfactory. This study verified the characteristics of circPUM1 in OSCC cells, subsequently generating dysregulated circPUM1 cell models, showing that circPUM1 promoted chemoresistance and natural killer (NK) cell toxicity. Furthermore, the transcription factor SP2 regulated the expression of circPUM1 in OSCC cells, circPUM1 acted as a molecular sponge for miR-770-5p. Moreover, Nucleosome Assembly Protein 1 Like 1 (NAP1L1) is a downstream target for miR-770-5p and essential for circPUM1-mediated cisplatin resistance and NK cell cytotoxicity in OSCC cells. The network composed of SP2, circPUM1, miR-770-5p and NAP1L1 in OSCC appears to be a promising avenue for the development of novel targets for diagnosing or treating OSCC.

The important role of miR-770 as a novel potential diagnostic and therapeutic target for human cancer and other diseases

MicroRNA-770 (miR-770) is an RNA gene, located on chromosome 14q32.2. It has important effects on the pathobiology of cancers and other human diseases. It is known to be a tumor suppressor in breast cancer, ovarian cancer, gastric cancer, non-small cell lung cancer, prostate cancer, and glioblastoma. In colorectal adenocarcinoma and oral squamous cell carcinoma, miR-770 is regarded as an oncogenic miRNA. In several disorders, miR-770 dysregulation has been recognized as a potential biomarker for disease diagnosis and prognosis. Dysregulation of miR-770 has also been demonstrated in non-malignant human disorders, including Alzheimer's disease, dilated cardiomyopathy, diabetic nephropathy, Hirschsprung's disease, osteoarthritis, silicosis, and type 2 diabetes mellitus. In the current review, we have obtained the miR-770 target genes, ontology, and related pathways. We have also provided a comprehensive review of miR-770 in both malignant and non-malignant disorders and explained its possible therapeutic implications.

Clinicopathological and prognostic value of lncRNA TPT1-AS1 in cancer: a systematic review study and meta-analysis

INTRODUCTION

Aberrant expression of lncRNAs in cancer cells can impact their key phenotypes. We aimed to summarize available evidence on clinicopathological and prognostic value of lncRNA TPT1-AS1 in cancer.

METHODS

A systematic search was performed on Medline and Embase databases using relevant key terms covering lncRNA TPT1-AS1, cancer, and clinical outcomes. The effect size estimates and their 95 % confidence interval (CI) were pooled using random-effects models. Meta- analyses were conducted using STATA 16.0 software.

RESULTS

Seventeen articles met our eligibility criteria. Tumor tissue compared to normal tissue showed increased level of lncRNA TPT1-AS1 expression (pooled standardized mean difference (95 % CI): 0.65 (0.52-0.79)). Overexpression of this lncRNA was a significant predictor for poor prognosis (Pooled log-rank test P-value < 0.001); in patients with high-level of lncRNA TPT1-AS1, the risk of death at five years was 1.40 times greater than their counterparts. The pooled Odds ratios for association lncRNA TPT1-AS1 with tumor stage, tumor size, and lymph node metastasis were 1.94 (95 % CI: 0.90-4.19, 8 studies, I² = 79.6 %), 2.33 (95 % CI: 1.31-4.14, 5 studies, I² = 40.0 %), and 1.89 (95 % CI: 1.08-3.36, 5 studies, I² = 61.7 %), respectively. Regarding the identified potential mechanisms, lncRNA TPT1-AS1 plays a role in cancer growth mainly by sponging miRNAs and regulating their downstream targets or controlling the expression of key cell cycle regulators.

CONCLUSION

In cancer patients, elevated expression of lncRNA TPT1-AS1 might be associated with a shorter Overall Survival, advanced stages, larger tumor size, and lymph node metastasis.

A review of literature: role of long noncoding RNA TPT1-AS1 in human diseases

Human diseases are multifactorial processes mainly driven by the intricate interactions of genetic and environmental factors. Long noncoding RNAs (lncRNAs) represent a type of non-coding RNAs with more than 200 nucleotides. Multiple studies have demonstrated that the dysregulation of lncRNAs is associated with complex biological as well as pathological processes through various mechanism, especially the regulation of gene transcription and related signal transduction pathways. Moreover, an increasing number of studies have explored lncRNA-based clinical applications in different diseases. For instance, the lncRNA Tumor Protein Translationally Controlled 1 (TPT1) Antisense RNA 1 (TPT1-AS1) was found to be dysregulated in several types of disease and strongly associated with patient prognosis and diverse clinical features. Recent studies have also documented that TPT1-AS1 modulates numerous biological processes through multiple mechanisms, including cell proliferation, apoptosis, autophagy, invasion, migration, radiosensitivity, chemosensitivity, stemness, and extracellular matrix (ECM) synthesis. Furthermore, TPT1-AS1 was regarded as a promising biomarker for the diagnosis, prognosis and treatment of several human diseases. In this review, we summarize the role of TPT1-AS1 in human diseases with the aspects of its expression, relevant clinical characteristics, molecular mechanisms, biological functions, and subsequent clinical applications.

Comparative mRNA/micro-RNA co-expression network drives melanomagenesis by promoting epithelial-mesenchymal transition and vasculogenic mimicry signaling

This study aimed to identify a novel disease-associated differentially co-expressed mRNA-microRNA (miRNA) that is associated with vasculogenic mimicry (VM) and epithelial-to-mesenchymal transition (EMT) network at different stages of melanoma. By applying weighted gene co-expression network analysis, we constructed a VM+EMT biological network with the available microarray dataset downloaded from a public database. Quantitative real-time PCR, immunohistochemical staining, and CD31-periodic acid solution dual staining were performed to confirm the expression of genes associated with EMT and VM formation in subjects with malignant melanoma (n = 18) and primary melanoma (n = 13) and in healthy subjects (n = 10). Our findings suggested that phosphatidylserine-specific phospholipase A1-alpha (PLA1A) and dermokine (DMKN) genes function as oncogenes that trigger VM and EMT processes during melanomagenesis on interaction with miR-370, miR-563, and miR-770-5p. PLA1A and DMKN genes can be considered potential VM+EMT network-based diagnostic biomarkers for distinguishing between melanoma patients. We postulate that a network with altered PLA1A/miR-563 and DMNK/miR-770-5p/miR-370 may contribute to melanomagenesis by triggering the EMT signaling pathway and VM formation. This study provides a potentially valuable approach for the early diagnosis and prognosis of melanoma progression.

Non-coding RNA-mediated autophagy in cancer: A protumor or antitumor factor?

Autophagy, usually referred to as macroautophagy, is a cytoprotective behavior that helps cells, especially cancer cells, escape crises. However, the role of autophagy in cancer remains controversial. The induction of autophagy is favorable for tumor growth, as it can degrade damaged cell components accumulated during nutrient deficiency, chemotherapy, or other stresses in a timely manner. Whereas the antitumor effect of autophagy might be closely related to its crosstalk with metabolism, immunomodulation, and other pathways. Recent studies have verified that lncRNAs and circRNAs modulate autophagy in carcinogenesis, cancer cells proliferation, apoptosis, metastasis, and chemoresistance via multiple mechanisms. A comprehensive understanding of the regulatory relationships between ncRNAs and autophagy in cancer might resolve chemoresistance and also offer intervention strategies for cancer therapy. This review systematically displays the regulatory effects of lncRNAs and circRNAs on autophagy in the contexts of cancer initiation, progression, and resistance to chemo- or radiotherapy and provides a novel insight into cancer therapy.

lncRNA TPT1‑AS1 knockdown inhibits liver cancer cell proliferation, migration and invasion

Long non-coding RNA (lncRNA) tumor protein translationally controlled 1 antisense RNA 1 (TPT1-AS1) serves as an oncogene in several tumors, including ovarian and cervical cancer. However, the functional role of TPT1-AS1 in liver cancer (LC) is not completely understood. The present study aimed to explore the role of TPT1-AS1 in LC. In this study, the reverse transcription-quantitative PCR results demonstrated that TPT1-AS1 expression was significantly upregulated in LC tissues and cell lines compared with adjacent paracancerous tissues and THLE-3 cells, respectively. Elevated TPT1-AS1 expression was significantly associated with TNM stage lymph node metastasis and poor prognosis in patients with LC, as determined via χ² and Kaplan-Meier survival analyses. By constructing TPT1-AS1 knockdown LC cell lines (HepG2 and SNU-182), loss-of-function experiments, including Cell Counting Kit-8, colony formation, flow cytometry, wound healing and Transwell assays, were performed to explore the function role of TPT1-AS1 in LC in vitro. The results demonstrated that TPT1-AS1 knockdown inhibited LC cell proliferation, G₁/S transition, migration and invasion compared with the small interfering RNA (si)-negative control (NC) group. Mechanistically, TPT1-AS1 knockdown markedly decreased CDK4, N-cadherin and Vimentin expression levels, but notably increased p21 and E-cadherin expression levels compared with the si-NC group. Therefore, the results of the present study suggested that TPT1-AS1 might serve as a promising therapeutic target for LC treatment.

miR-770-5p inhibits the activation of pulmonary fibroblasts and silica-induced pulmonary fibrosis through targeting TGFBR1

Silicosis is a devastating interstitial lung disease arising from long-term exposure to inhalable silica. Regrettably, no therapy currently can effectively reverse the silica-induced fibrotic lesion. Emerging evidence has indicated that the dysregulation of microRNAs is involved in silica-induced pulmonary fibrosis. The aim of this study is to explore the expression pattern and underlying mechanisms of miR-770-5p in silica-induced pulmonary fibrosis. Consistent with our previous miRNA microarray analysis, the results of qRT-PCR showed that miR-770-5p expression was downregulated in silica-induced pulmonary fibrosis in humans and animal models. Administration of miR-770-5p agomir significantly reduced the fibrotic lesions in the lungs of mice exposed to silica dust. MiR-770-5p also exhibited a dramatic reduction in TGF-β1-activated human pulmonary fibroblasts (MRC-5). Transfection of miR-770-5p mimics significantly decreased the viability, migration ability, and S/G0 phase distribution, as well as the expression of fibronectin, collagen I, and α-SMA in TGF-β1-treated MRC-5 cells. Transforming growth factor-β receptor 1 (TGFBR1) was confirmed as a direct target of regulation by miR-770-5p. The expression of TGFBR1 was significantly increased in pulmonary fibrosis. Knockdown of TGFBR1 blocked the transduction of the TGF-β1 signaling pathway and attenuated the activation of MRC-5 cells, while overexpression of TGFBR1 effectively restored the activation of MRC-5 cells inhibited by miR-770-5p. Together, our results demonstrated that miR-770-5p exerted an anti-fibrotic effect in silica-induced pulmonary fibrosis by targeting TGFBR1. Targeting miR-770-5p might provide a new therapeutic strategy to prevent the abnormal activation of pulmonary fibroblasts in silicosis.

A novel circular RNA, circPUS7 promotes cadmium-induced transformation of human bronchial epithelial cells by regulating Kirsten rat sarcoma viral oncogene homolog expression via sponging miR-770

Cadmium is a human carcinogen, which induces cancers by mechanisms that are not fully understood. Induction of oxidative stress, apoptosis resistance, genotoxic effects, and epigenetic modulations have been indicated to regulate cadmium-induced carcinogenesis. Circular RNAs are epigenetic regulators that have been recognized to play essential roles in carcinogenesis. Yet, the involvement of circular RNAs in cadmium carcinogenesis remains unclear. In this study, a novel circular RNA, circPUS7, was identified and described for the first time. CircPUS7 was significantly upregulated at week 12, 16, and 20 during the cadmium-induced transformation of human bronchial epithelial BEAS-2B cells. Knockdown of circPUS7 in cadmium-transformed BEAS-2B (T-BEAS-2B) cells significantly attenuated transformation markers including cell proliferation, migration, invasion, and anchorage-independent growth. Moreover, circPUS7 promoted malignant phenotypes by competitively binding with miR-770. Overexpression of miR-770 significantly inhibited the transformation properties of T-BEAS-2B cells while inhibition of miR-770 potently reversed the inhibitory effects of circPUS7 knockdown in proliferation, migration, invasion, and anchorage-independent growth of the T-BEAS-2B cells. Kirsten rat sarcoma viral oncogene homolog (KRAS), which was increased synchronically with circPUS7 during cadmium-induced cell transformation, was regulated by circPUS7 through sponging miR-770. In summary, our findings demonstrate that circPUS7 promotes cadmium-induced cell transformation through sponging miR-770 to regulate KRAS expression, providing a new perspective with the involvement of circular RNAs to further understand the mechanisms of cadmium carcinogenesis.

Long non-coding RNA TPT1-AS1 sensitizes breast cancer cell to paclitaxel and inhibits cell proliferation by miR-3156-5p/caspase 2 axis

Long non-coding RNAs (lncRNAs) are key modulators during cancer progression. Application of using lncRNA expression to evaluate patient prognosis and sensitivity to treatment is highly anticipated, yet the expression and mechanism of many lncRNAs remain unknown. Herein, we projected for the investigation of TPT1-AS1 function in breast cancer. TPT1-AS1 was assessed by bioinformatic analysis of publicly available datasets and quantitative real-time PCR (qRT-PCR). Cell sensitivity to paclitaxel and cell proliferation was measured by flow cytometry and CCK-8. Interaction among TPT1-AS1, microRNA (miRNA, miR)-3156-5p and Caspase 2 (CASP2) was studied by bioinformatic analysis, qRT-PCR, western blot as well as dual luciferase reporter assay. Herein, TPT1-AS1 was significantly diminished in breast cancer from publicly available datasets and our collected samples. In breast cancer cells, TPT1-AS1 overexpression repressed cell proliferation and sensitized breast cancer cells to paclitaxel. RegRNA 2.0 predicted a potential interaction between TPT1-AS1 and miR-3156-5p which was confirmed by qRT-PCR as well as dual luciferase reporter assay. CASP2, a proapoptotic gene, was corroborated to be targeted by miR-3156-5p. Meanwhile, TPT1-AS1 upregulated CASP2 in breast cancer cells, and its biological function was reversed by CASP2 knockdown. Collectively, TPT1-AS1 diminished cell proliferation and sensitized cells to chemotherapy by sponging miR-3156-5p and upregulating CASP2, acting as a biomarker for patients with breast cancer.

Roles of Long Noncoding RNAs in Conferring Glioma Progression and Treatment

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

CircABCC3 knockdown inhibits glioblastoma cell malignancy by regulating miR-770-5p/SOX2 axis through PI3K/AKT signaling pathway

BACKGROUND

Circular RNAs (circRNAs) are found to regulate glioblastoma evolution. However, the role of circ-ATP binding cassette subfamily C member 3 (circABCC3) in glioblastoma process is still unknown. In this study, the effects of circABCC3 on glioblastoma tumorigenesis and underlying mechanism were revealed.

METHODS

The expression levels of circABCC3, microRNA-770-5p (miR-770-5p) and sex determining region Y-box protein 2 (SOX2) mRNA were determined by quantitative real-time polymerase chain reaction (qRT-PCR). The expression of phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway-related proteins and SOX2 protein was detected by western blot analysis. Cell proliferation and invasion were severally investigated by cell colony formation and transwell invasion assays. Cell migration was demonstrated by transwell migration and wound-healing assays. Cell apoptosis was revealed by flow cytometry analysis. Tube formation was investigated by tube formation assay. The associated relationship between miR-770-5p and circABCC3 or SOX2 was predicted by starbase or targetscan online database, and identified by dual-luciferase reporter assay, RNA immunoprecipitation assay or RNA pull-down assay. The impacts of circABCC3 knockdown on glioblastoma growth in vivo were revealed by in vivo assay.

RESULTS

CircABCC3 and SOX2 expression were dramatically upregulated, while miR-770-5p expression was apparently downregulated in glioblastoma tissues and cells compared with control groups. CircABCC3 expression was higher in stage III glioblastoma tissues than in stage I + II glioblastoma tissues with close correlation with tumor-node-metastasis (TNM) stage. CircABCC3 absence inhibited cell proliferation, migration, invasion, tube formation and the activation of PI3K/AKT pathway, whereas induced cell apoptosis in glioblastoma. Additionally, circABCC3 acted as a sponge for miR-770-5p, and miR-770-5p targeted SOX2. MiR-770-5p inhibitors impaired the impacts of circABCC3 silencing on glioblastoma progression, angiogenesis and PI3K/AKT pathway. Furthermore, circABCC3 knockdown repressed tumor growth in vivo.

CONCLUSION

CircABCC3 regulated glioblastoma development via miR-770-5p/SOX2 axis through PI3K/AKT pathway. This finding lays a theoretical foundation for studying circRNA-directed therapy for glioblastoma.

lncRNA FBXL19-AS1 is a diagnosis biomarker for paediatric patients with acute myeloid leukemia

BACKGROUND

Long non-coding RNAs (lncRNA) have emerged as novel clinical biomarkers and therapeutic targets for various tumors because of their disease- and stage-restricted expression. lncRNA FBXL19 antisense RNA 1 (FBXL19-AS1) expression has been confirmed to be up-regulated in several tumors. However, its expression and effects in paediatric acute myeloid leukemia (AML) have not been elucidated.

METHODS

Serum FBXL19-AS1 expression was determined in 137 AML patients compared to 43 healthy controls ( < 0.01).

RESULTS

Using receiver operating characteristic curve analysis, we observed that serum FBXL19-AS1 provided the highly diagnostic performance for the detection of AML (AUC = 0.841, < 0.001). We also examined the association between serum FBXL19-AS1 expression and clinicopathological factors, finding that its high expression was associated with French-American-British classification ( = 0.011) and cytogenetics ( = 0.021). Survival assays with the Kaplan-Meier method revealed that the overall survival ( = 0.0088) and disease-free-survival ( = 0.0027) of AML patients with high serum FBXL19-AS1 levels were distinctly shorter compared to those with low serum FBXL19-AS1 levels. More importantly, Multivariate analysis identified serum FBXL19-AS1 overexpression as an independent unfavorable prognostic factor for both overall survival and disease-free-survival of AML patients.

CONCLUSIONS

Overall, our findings revealed that high expression of serum FBXL19-AS1 might be useful as a novel prognostic and diagnostic biomarker for AML patients.

Identification of differentially expressed mRNA and the Hub mRNAs modulated by lncRNA Meg3 as a competing endogenous RNA in brown adipose tissue of mice on a high-fat diet

Obesity is associated with insulin resistance, diabetes, and obesity-related metabolic disorders. Brown adipocytes have emerged as potential targets for the treatment of obesity and obesity-related diseases. However, changes that occur in brown adipose tissue during various stages of high fat diet (HFD)-induced obesity remain poorly understood. The present study aimed to determine the changes occurring in brown adipose tissue during various stages of an HFD by analyzing two microarray expression profiles. A total of 1,337 differentially expressed RNAs (DE RNAs) were identified between the HFD and ND groups, using the limma package in R. The DE RNAs included 1,249 mRNAs, 74 long non coding RNAs (lncRNAs), and 14 pseudogenes. Functional annotation of the DE mRNAs, including GO terms and KEGG pathways were identified using the Database for Annotation, Visualization, and Integrated Discovery. A protein-protein interaction network was constructed using STRING and clusters were obtained through the Molecular Complex Detection plug-in. In the present study, the lncRNA,maternally expressed gene 3 (Meg3), was identified as the DE lncRNA with a significant fold change. The network of Meg3 as a ceRNA was constructed, which demonstrated that Meg3 modulated five hub DE mRNAs via competitive binding to microRNAs.

Long noncoding RNA LIFR-AS1 suppresses proliferation, migration and invasion and promotes apoptosis through modulating miR-4262/NF-κB pathway in glioma

AIM

This study aimed to explore the role of lncRNA leukemia inhibitory factor receptor antisense RNA 1 (LIFR-AS1) on glioma and its underlying molecular mechanism.

METHODS

The expression of LIFR-AS1 and miR-4262 was detected by quantitative real-time polymerase chain reaction (qRT-RCR) in both glioma tissues and cell lines. Colony formation assay, 5-ethynyl-20-deoxyuridine (EdU) assay, flow cytometry and transwell assay were respectively conducted to detect cell clones, proliferation, apoptosis, migration and invasion. The effect of LIFR-AS1 on the chemoresistance to temozolomide (TMZ) of glioma cells was also analyzed. In addition, dual-luciferase reporter gene assay was performed to evaluate the luciferase activity. The expressions of nuclear factor-κB (NF-κB) p65, p-NF-κB p65 and inhibitor of κBα (IκBα) in glioma cells were measured by western blot.

RESULTS

LIFR-AS1 was lowly expressed and miR-4262 was highly expressed in glioma tissues and cell lines. LIFR-AS1 overexpression inhibited the proliferation, migration and invasion and promoted apoptosis of glioma cells. LIFR-AS1 overexpression also reduced the chemoresistance to TMZ of glioma cells. Moreover, LIFR-AS1 overexpression suppressed the activation of NF-κB signaling pathway in glioma cells. miR-4262 was the target gene of LIFR-AS1. We also found that miR-4262 abrogated the functions of LIFR-AS1 on cell proliferation, apoptosis, migration and invasion of glioma cells in the NF-κB pathway.

CONCLUSION

LIFR-AS1 could suppress the proliferation, migration and invasion and promote the apoptosis through modulating miR-4262/NF-κB pathway in glioma.

Complex Analysis of Retroposed Genes' Contribution to Human Genome, Proteome and Transcriptome

Gene duplication is a major driver of organismal evolution. One of the main mechanisms of gene duplications is retroposition, a process in which mRNA is first transcribed into DNA and then reintegrated into the genome. Most gene retrocopies are depleted of the regulatory regions. Nevertheless, examples of functional retrogenes are rapidly increasing. These functions come from the gain of new spatio-temporal expression patterns, imposed by the content of the genomic sequence surrounding inserted cDNA and/or by selectively advantageous mutations, which may lead to the switch from protein coding to regulatory RNA. As recent studies have shown, these genes may lead to new protein domain formation through fusion with other genes, new regulatory RNAs or other regulatory elements. We utilized existing data from high-throughput technologies to create a complex description of retrogenes functionality. Our analysis led to the identification of human retroposed genes that substantially contributed to transcriptome and proteome. These retrocopies demonstrated the potential to encode proteins or short peptides, act as cis- and trans- Natural Antisense Transcripts (NATs), regulate their progenitors’ expression by competing for the same microRNAs, and provide a sequence to lncRNA and novel exons to existing protein-coding genes. Our study also revealed that retrocopies, similarly to retrotransposons, may act as recombination hot spots. To our best knowledge this is the first complex analysis of these functions of retrocopies.

Long Non-coding RNA MINCR Regulates miR-876-5p/GSPT1 Axis to Aggravate Glioma Progression

Emerging evidence underlined the crucial roles played by long non-coding RNAs (lncRNAs) in glioma. MINCR has been reported in multiple malignancies. Here, we studied its function and potential mechanism in glioma, which remain unclear. Gene expressions were analyzed by qRT-PCR assay. Both in vitro and in vivo assays were conducted to evaluate the cellular function of MINCR in glioma. The subcellular situation of MINCR was detected by subcellular fractionation and FISH assays. Luciferase reporter, RNA pull-down and RNA immunoprecipitation (RIP) assays were combined to investigate potential mechanisms of relevant genes. MINCR was up-regulated in glioma. MINCR depletion markedly refrained glioma cell proliferation, migration and invasion via sponging miR-876-5p. MiR-876-5p suppressed the malignant behaviors of glioma via binding to GSPT1. MINCR shared the binding sites with the 3'-untranslated region of GSPT1 and prevented the binding of miR-876-5p to GSPT1 mRNA, thus up-regulating the level of GSPT1. Moreover, miR-876 inhibition and GSPT1 up-regulation counteracted the functional effect induced by silencing MINCR on glioma progression. Our findings uncovered that MINCR might aggravated glioma cell proliferation and migration via acting as competing endogenous RNA (ceRNA), indicating prospective novel therapeutic target for glioma.

Long non-coding RNA TPT1-AS1 promotes angiogenesis and metastasis of colorectal cancer through TPT1-AS1/NF90/VEGFA signaling pathway

LncRNAs have been proven closely correlated to tumor progression. A recent study identified LncRNA TPT1-AS1 (TPT1-AS1) as one of the liver-metastasis associated LncRNAs in colorectal cancer (CRC). In this study, we report that TPT1-AS1 is upregulated in CRC tissues, which is associated with poor prognosis. Functional assays unravel a pro-angiogenesis and metastasis role of TPT1-AS1. Mechanistically, Flexmap 3D assays reveal that TPT1-AS1 upregulates the VEGFA secretion in CRC cells. RNA immunoprecipitation and mRNA stability assays further show that TPT1-AS1 interacts with nuclear factor 90 (NF90) and subsequently promotes the association between NF90 and VEGFA mRNA, which leads to the upregulation of VEGFA mRNA stability. Therefore, we elucidate a new regulatory mechanism of TPT1-AS1 in CRC angiogenesis and targeting the TPT1-AS1/NF90/VEGFA axis may provide a useful strategy for diagnosis and treatment for colorectal cancer patients.