Knockdown of LncRNA SCAMP1 suppressed malignant biological behaviours of glioma cells via modulating miR-499a-5p/LMX1A/NLRC5 pathway

Retracted article: Knockdown of long non-coding RNA AGAP2-AS1 suppresses the proliferation and metastasis of glioma by targeting microRNA-497-5p

Yi Sun, Yulong Shen and Xing Li. Knockdown of long non-coding RNA AGAP2-AS1 suppresses the proliferation and metastasis of glioma by targeting microRNA-497-5p. Bioengineered. 2021 Oct. doi: 10.1080/21655979.2021.1995573.Since publication, significant concerns have been raised about the compliance with ethical policies for human research and the integrity of the data reported in the article.When approached for an explanation, the authors provided some original data but were not able to provide all the necessary supporting information. As verifying the validity of published work is core to the scholarly record's integrity, we are retracting the article. All authors listed in this publication have been informed.We have been informed in our decision-making by our editorial policies and the COPE guidelines. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as 'Retracted.'

CircATXN7 regulates the proliferation and invasion of esophageal cancer cells through miR-4319/NLRC5

BACKGROUND

This study aimed to explore the molecular mechanism through which circular RNA of ataxin 7 (circATXN7) regulates the proliferation and invasion of esophageal cancer (EC) cells via microRNA (miR)-4319/NLR family CARD domain containing 5 (NLRC5).

METHODS

The localization of circATXN7 in EC cells was determined by RNA fluorescent in situ hybridization (RNA-FISH). The mRNA levels of circATXN7, miR-4319, and NLRC5 were quantified by reverse transcription-polymerase chain reactions. The binding activity of circATXN7 to miR-4319 was assessed using RNA-binding protein immunoprecipitation. Whether circATXN7 regulates the proliferation of EC cells via miR-4319 was explored using dual-luciferase reporter gene colony formation assays. Protein levels were quantified by western blot. The effect of NLRC5 on the proliferation and invasion of EC cells was examined using colony formation and Transwell assays. A subcutaneous transplanted tumor nude mouse model was established to observe the effect of circATXN7 on the proliferation of EC cells in vivo.

RESULTS

circATXN7 localized mainly to the cytoplasm. Overexpression or inhibition of miR-4319 significantly regulated the proliferation of EC cells, while circATXN7 competitively inhibited miR-4319 expression. Overexpression of miR-4319 significantly inhibited NLRC5 expression, indicating NLRC5 is a downstream regulatory target of miR-4319. circATXN7 influenced NLRC5 expression via miR-4319. In vivo tumor formation experiments in nude mice revealed that knocking down circATXN7 regulated NLRC5 expression via miR-4319 and significantly inhibited the proliferation of EC cells.

CONCLUSIONS

In vitro cell and in vivo animal experiments showed that circATXN7 regulates the proliferation, invasion, and migration of EC cells through the miR-4319/NLRC5 signaling pathway.

Critical roles of lncRNA-mediated autophagy in urologic malignancies

Urologic oncology is a significant public health concern on a global scale. Recent research indicates that long chain non-coding RNAs (lncRNAs) and autophagy play crucial roles in various cancers, including urologic malignancies. This article provides a summary of the latest research findings, suggesting that lncRNA-mediated autophagy could either suppress or promote tumors in prostate, kidney, and bladder cancers. The intricate network involving different lncRNAs, target genes, and mediated signaling pathways plays a crucial role in urological malignancies by modulating the autophagic process. Dysregulated expression of lncRNAs can disrupt autophagy, leading to tumorigenesis, progression, and enhanced resistance to therapy. Consequently, targeting particular lncRNAs that control autophagy could serve as a dependable diagnostic tool and a promising prognostic biomarker in urologic oncology, while also holding potential as an effective therapeutic approach.

Targeting long non-coding RNAs in cancer therapy using CRISPR-Cas9 technology: A novel paradigm for precision oncology

Cancer is the second leading cause of death worldwide, despite recent advances in its identification and management. To improve cancer patient diagnosis and care, it is necessary to identify new biomarkers and molecular targets. In recent years, long non-coding RNAs (lncRNAs) have surfaced as important contributors to various cellular activities, with growing proof indicating their substantial role in the genesis, development, and spread of cancer. Their unique expression profiles within specific tissues and their wide-ranging functionalities make lncRNAs excellent candidates for potential therapeutic intervention in cancer management. They are implicated in multiple hallmarks of cancer, such as uncontrolled proliferation, angiogenesis, and immune evasion. This review article explores the innovative application of CRISPR-Cas9 technology in targeting lncRNAs as a cancer therapeutic strategy. The CRISPR-Cas9 system has been widely applied in functional genomics, gene therapy, and cancer research, offering a versatile platform for lncRNA targeting. CRISPR-Cas9-mediated targeting of lncRNAs can be achieved through CRISPR interference, activation or the complete knockout of lncRNA loci. Combining CRISPR-Cas9 technology with high-throughput functional genomics makes it possible to identify lncRNAs critical for the survival of specific cancer subtypes, opening the door for tailored treatments and personalised cancer therapies. CRISPR-Cas9-mediated lncRNA targeting with other cutting-edge cancer therapies, such as immunotherapy and targeted molecular therapeutics can be used to overcome the drug resistance in cancer. The synergy of lncRNA research and CRISPR-Cas9 technology presents immense potential for individualized cancer treatment, offering renewed hope in the battle against this disease.

NLRC5 potentiates anti-tumor CD8+ T cells responses by activating interferon-β in endometrial cancer

OBJECTIVES

NLR family CARD domain containing 5 (NLRC5) could promote major histocompatibility complex class I (MHC-I)-dependent CD8+ T cell-mediated anticancer immunity. In this study, the immunosurveillance role and underlying mechanisms of NLRC5 in endometrial cancer (EC) were characterized.

METHODS

CD8+ T cells were separated from healthy women's peripheral blood by using magnetic beads. The effect of NLRC5 and interferon-β (IFN-β) on immunosurveillance of EC were examined through a mouse tumor model and a CD8+ T cell-EC cell coculture system after NLRC5 overexpression and IFN-β overexpression or depletion. The effect of NLRC5 on IFN-β expression was examined with gain- and loss-of-function experiments.

RESULTS

NLRC5 overexpression in the EC cell and CD8+ T cell coculture system inhibited EC cell proliferation and migration and promoted EC cell apoptosis and CD8+ T cell proliferation. In vivo, NLRC5 overexpression increased the proportion of CD8+ T cells and inhibited EC progression. Furthermore, IFN-β overexpression in the EC cell and CD8+ T cell coculture system activated CD8+ T cell proliferation; however, genetic depletion of IFN-β exerted the opposite effects. In addition, NLRC5 could negatively regulate IFN-β expression in EC cells. Mechanistically, NLRC5 potentiated the antitumor responses of CD8+ T cells to EC by activating IFN-β.

CONCLUSIONS

Taken together, our findings demonstrated that NLRC5 potentiates anti-tumor CD8+ T cells responses by activating interferon-β in EC, suggesting that genetically escalated NLRC5 and IFN-β may act as potential candidates for the clinical translation of adjuvant immunotherapies to patients with EC.

Insight into Cancer Immunity: MHCs, Immune Cells and Commensal Microbiota

Cancer cells circumvent immune surveillance via diverse strategies. In accordance, a large number of complex studies of the immune system focusing on tumor cell recognition have revealed new insights and strategies developed, largely through major histocompatibility complexes (MHCs). As one of them, tumor-specific MHC-II expression (tsMHC-II) can facilitate immune surveillance to detect tumor antigens, and thereby has been used in immunotherapy, including superior cancer prognosis, clinical sensitivity to immune checkpoint inhibition (ICI) therapy and tumor-bearing rejection in mice. NK cells play a unique role in enhancing innate immune responses, accounting for part of the response including immunosurveillance and immunoregulation. NK cells are also capable of initiating the response of the adaptive immune system to cancer immunotherapy independent of cytotoxic T cells, clearly demonstrating a link between NK cell function and the efficacy of cancer immunotherapies. Eosinophils were shown to feature pleiotropic activities against a variety of solid tumor types, including direct interactions with tumor cells, and accessorily affect immunotherapeutic response through intricating cross-talk with lymphocytes. Additionally, microbial sequencing and reconstitution revealed that commensal microbiota might be involved in the modulation of cancer progression, including positive and negative regulatory bacteria. They may play functional roles in not only mucosal modulation, but also systemic immune responses. Here, we present a panorama of the cancer immune network mediated by MHCI/II molecules, immune cells and commensal microbiota and a discussion of prospective relevant intervening mechanisms involved in cancer immunotherapies.

NLRC5-CIITA Fusion Protein as an Effective Inducer of MHC-I Expression and Antitumor Immunity

Aggressive tumors evade cytotoxic T lymphocytes by suppressing MHC class-I (MHC-I) expression that also compromises tumor responsiveness to immunotherapy. MHC-I defects strongly correlate to defective expression of NLRC5, the transcriptional activator of MHC-I and antigen processing genes. In poorly immunogenic B16 melanoma cells, restoring NLRC5 expression induces MHC-I and elicits antitumor immunity, raising the possibility of using NLRC5 for tumor immunotherapy. As the clinical application of NLRC5 is constrained by its large size, we examined whether a smaller NLRC5-CIITA fusion protein, dubbed NLRC5-superactivator (NLRC5-SA) as it retains the ability to induce MHC-I, could be used for tumor growth control. We show that stable NLRC5-SA expression in mouse and human cancer cells upregulates MHC-I expression. B16 melanoma and EL4 lymphoma tumors expressing NLRC5-SA are controlled as efficiently as those expressing full-length NLRC5 (NLRC5-FL). Comparison of MHC-I-associated peptides (MAPs) eluted from EL4 cells expressing NLRC5-FL or NLRC5-SA and analyzed by mass spectrometry revealed that both NLRC5 constructs expanded the MAP repertoire, which showed considerable overlap but also included a substantial proportion of distinct peptides. Thus, we propose that NLRC5-SA, with its ability to increase tumor immunogenicity and promote tumor growth control, could overcome the limitations of NLRC5-FL for translational immunotherapy applications.

Nucleotide-Binding Oligomerization Domain (NOD)-Like Receptor Subfamily C (NLRC) as a Prognostic Biomarker for Glioblastoma Multiforme Linked to Tumor Microenvironment: A Bioinformatics, Immunohistochemistry, and Machine Learning-Based Study

Purpose

Glioblastoma multiforme (GBM) remains the deadliest primary brain tumor. We aimed to illuminate the role of nucleotide-binding oligomerization domain (NOD)-like receptor subfamily C (NLRC) in GBM.

Patients and Methods

Based on public database data (mainly The Cancer Genome Atlas [TCGA]), we performed bioinformatics analysis to visually evaluate the role and mechanism of NLRCs in GBM. Then, we validated our findings in a glioma tissue microarray (TMA) by immunohistochemistry (IHC), and the prognostic value of NOD1 was assessed via random forest (RF) models.

Results

In GBM tissues, the expression of NLRC members was significantly increased, which was related to the low survival rate of GBM. Additionally, Cox regression analysis revealed that the expression of NOD1 (among NLRCs) served as an independent prognostic marker. A nomogram based on multivariate analysis proved the effective predictive performance of NOD1 in GBM. Enrichment analysis showed that high expression of NOD1 could regulate extracellular structure, cell adhesion, and immune response to promote tumor progression. Then, immune infiltration analysis showed that NOD1 overexpression correlated with an enhanced immune response. Then, in a glioma TMA, the results of IHC revealed that the increase in NOD1 expression indicated high recurrence and poor prognosis of human glioma. Furthermore, the expression level of NOD1 showed good prognostic value in the TMA cohort via RF.

Conclusion

The value of NOD1 as a biomarker for GBM was demonstrated. The possible mechanisms may lie in the regulatory role of NLRC-related pathways in the tumor microenvironment.

A novel prognostic related lncRNA signature associated with amino acid metabolism in glioma

Background

Glioma is one of the deadliest malignant brain tumors in adults, which is highly invasive and has a poor prognosis, and long non-coding RNAs (lncRNAs) have key roles in the progression of glioma. Amino acid metabolism reprogramming is an emerging hallmark in cancer. However, the diverse amino acid metabolism programs and prognostic value remain unclear during glioma progression. Thus, we aim to find potential amino-related prognostic glioma hub genes, elaborate and verify their functions, and explore further their impact on glioma.

Methods

Glioblastoma (GBM) and low-grade glioma (LGG) patients' data were downloaded from TCGA and CCGA datasets. LncRNAs associated with amino acid metabolism were discriminated against via correlation analysis. LASSO analysis and Cox regression analysis were conducted to identify lncRNAs related to prognosis. GSVA and GSEA were performed to predict the potential biological functions of lncRNA. Somatic mutation data and CNV data were further built to demonstrate genomic alterations and the correlation between risk scores. Human glioma cell lines U251 and U87-MG were used for further validation in vitro experiments.

Results

There were eight amino-related lncRNAs in total with a high prognostic value that were identified via Cox regression and LASSO regression analyses. The high risk-score group presented a significantly poorer prognosis compared with the low risk-score group, with more clinicopathological features and characteristic genomic aberrations. Our results provided new insights into biological functions in the above signature lncRNAs, which participate in the amino acid metabolism of glioma. LINC01561 is one of the eight identified lncRNAs, which was adopted for further verification. In in vitro experiments, siRNA-mediated LINC01561 silencing suppresses glioma cells' viability, migration, and proliferation.

Conclusion

Novel amino-related lncRNAs associated with the survival of glioma patients were identified, and a lncRNA signature can predict glioma prognosis and therapy response, which possibly has vital roles in glioma. Meanwhile, it emphasized the importance of amino acid metabolism in glioma, particularly in providing deeper research at the molecular level.

ceRNA network of lncRNA MIR210HG/miR-377-3p/LMX1A in malignant proliferation of glioma cells

BACKGROUND

Glioma represents the most heterogeneous and malignant form of brain tumor with a poor prognosis. The long non-coding RNA (LncRNA)-mediated competing endogenous RNA (ceRNA) network plays a regulatory role in cancer progression.

OBJECTIVES

The present study was conducted to expound on the role of lncRNA MIR210 host gene (MIR210HG)-mediated ceRNA mechanism in the malignant proliferation of glioma cells and provide a novel theoretical basis for the treatment of glioma.

METHODS

Expression levels of lncRNA MIR210HG, microRNA (miR)-377-3p, and LIM homeobox transcription factor 1 alpha (LMX1A) in glioma tissues and cells were determined by reverse-transcription quantitative polymerase chain reaction. Then, cell proliferation was assessed by cell counting kit-8 and colony formation assays. After that, the subcellular localization of lncRNA MIR210HG was analyzed by subcellular fractionation assay and the bindings of miR-377-3p to lncRNA MIR210HG and LMX1A were analyzed by the dual-luciferase assay. Glioma cells were transfected with si-MIR210HG, miR-377-3p inhibitor, or overexpressed-LMX1A vectors to evaluate their effects on the malignant proliferation of glioma cells.

RESULTS

LncRNA MIR210HG was elevated in glioma tissues and cells and inhibition of lncRNA MIR210HG reduced the proliferation potential of glioma cells. LncRNA MIR210HG targeted and inhibited miR-377-3p and miR-377-3p targeted and inhibited LMX1A transcription. miR-377-3p downregulation or LMX1A overexpression reversed the inhibition of silencing lncRNA MIR210HG on glioma cell proliferation.

CONCLUSION

LncRNA MIR210HG was upregulated in glioma tissues and cells and inhibition of lncRNA MIR210HG suppressed glioma cell proliferation through promoting miR-377-3p and repressing LMX1A.

Circular RNA circ_0079593 facilitates glioma development via modulating miR-324-5p/XBP1 axis

Glioma is a common brain tumor with high mortality. Circular RNAs (circRNAs) play crucial roles in tumor occurrence and development. However, the function and molecular basis of circ_0079593 in glioma remain unknown. Quantitative real-time PCR (qPCR) and Western blot were used for expression determination of circ_0079593, microRNA-324-5p (miR-324-5p) and X-box binding protein 1 (XBP1). Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry, transwell assays, and tube formation assay were employed to evaluate cell functions. Glycolysis was determined via detecting glucose consumption, lactate production and ATP level. The binding relationship between miR-324-5p and circ_0079593 or XBP1 was validated by dual-luciferase reporter assay and RNA Immunoprecipitation (RIP) assay. Besides, xenograft assay was applied to test tumor growth in vivo. Circ_0079593 and XBP1 levels were elevated, while miR-324-5p level was declined in glioma. Silencing of circ_0079593 restrained proliferation, mobility, angiogenesis and glycolysis and induced apoptosis in glioma cells. Circ_0079593 accelerated glioma progression via sequestering miR-324-5p, one of the targets of circ_0079593. XBP1 was a target gene of miR-324-5p, and miR-324-5p alleviated the malignant growth of glioma by repressing XBP1. Furthermore, silence of circ_0079593 hindered tumor growth in vivo. Circ_0079593 contributed to the malignant evolution of glioma via modulating miR-324-5p and downstream XBP1 gene, suggesting that circ_0079593 might be a promising therapeutic target for glioma. Circ_0079593 was boosted in glioma. Circ_0079593 depletion restrained glioma progression. Circ_0079593 triggered glioma development via miR-324-5p/XBP1 axis. Circ_0079593 silence suppressed glioma tumorigenesis in vivo.

Dual role of pseudogene TMEM198B in promoting lipid metabolism and immune escape of glioma cells

Dysregulation of pseudogenes, enhancement of fatty acid synthesis and formation of immunosuppressive microenvironment are important factors that promote the malignant progression of glioma. It is of great significance to search for the molecular mechanism of interaction between the three and then perform targeted interference for improving the treatment of glioma. In this study, we found that pseudogene transmembrane protein 198B (TMEM198B) was highly expressed in glioma tissues and cell lines, and it could promote malignant progression of glioma by regulating lipid metabolism reprogramming and remodeling immune microenvironment. Applying the experimental methods of gene interference, lipidomics and immunology, we further confirmed that TMEM198B promoted PLAG1 like zinc finger 2 (PLAGL2) expression by mediating tri-methylation of histone H3 on lysine 4 (H3K4me3) of PLAGL2 through binding to SET domain containing 1B (SETD1B). Increased PLAGL2 could transcriptional activate ATP citrate lyase (ACLY) and ELOVL fatty acid elongase 6 (ELOVL6) expression, and then influenced the biological behaviors of glioma cells via enhancing the de novo lipogenesis and fatty acid acyl chain elongation. At the same time, TMEM198B promoted macrophages lipid accumulation and intensification of fatty acid oxidation (FAO) through glioma-derived exosomes (GDEs), further induced macrophages to M2 polarization, which subsequently facilitated immune escape of glioma cells. In conclusion, our present study clarifies that the TMEM198B/PLAGL2/ACLY/ELOVL6 pathway conducts crucial regulatory effects on the malignant progression of glioma, which provides novel targets and new ideas for molecular targeted therapy and immunotherapy of glioma.

Expression pattern of NLRC5 in the postnatal mouse brain

Nucleotide oligomerization domain-like receptors (NLRs), belonging to a large family of pattern recognition receptors, participate in the host's first line of defense against invading pathogens. Caspase recruitment domain containing 5 (NLRC5), the largest member in the NLR family, is demonstrated to be involved in the innate immune response and inflammatory diseases far and wide. Recent studies report that NLRC5 is associated with some central nervous system (CNS) diseases. Besides, NLRC5 is a mastery regulator for the expression of MHC class I both in the immune system and the CNS, while MHC class I is expressed and exerts its function in the brain. Therefore, it is necessary to investigate the expression pattern of NLRC5 in the developing and adult CNS. In our study, postnatal brain sections of C57BL/6 J mice are analyzed for the expression of NLRC5 protein by immunofluorescence. In the postnatal stages of developing telencephalon, NLRC5 exhibits a spatial and temporal expression pattern. NLRC5 is time-specifically expressed in subfields of hippocampus and different layers of prefrontal cortex. Moreover, it is shown that NLRC5 is highly cell type specific. It can be expressed in large quantities by neurons and microglia, but rarely expressed by astrocytes. Taken together, our research is important for further understanding the biological characteristics of NLRC5 and its function in the CNS.

LncRNA SCAMP1 disrupts the balance between miR-26a-5p and ZEB2 to promote osteosarcoma cell viability and invasion

Osteosarcoma often occurs in children and adolescents and affects their health. The survival rate of osteosarcoma patients is unsatisfactory due to the lack of early detection and metastasis development and drug resistance. Hence, dissection of molecular insight into osteosarcoma initiation and progression is pivotal to provide the new therapeutic strategy. In recent years, long noncoding RNAs (lncRNAs) have burst into stage in osteosarcoma development and malignant behaviors. LncRNA SCAMP1 has been discovered to play an essential role in carcinogenesis and progression. However, the mechanisms of lncRNA SCAMP1-involved tumorigenesis have not been reported in human osteosarcoma. In this study, we utilized multiple cellular biological approaches to determine the function of lncRNA SCAMP1 in osteosarcoma cells. Moreover, we performed several molecular biological approaches to define the mechanism by which lncRNA SCAMP1 regulated cell viability and invasion in osteosarcoma. We dissected that lncRNA SCAMP1 promoted progression of osteosarcoma via modulation of miR-26a-5p/ZEB2 axis. In conclusion, targeting lncRNA SCAMP1 and its downstream targets, miR-26a-5p and ZEB2, might be a useful approach for osteosarcoma therapy.

Inhibition of NLRC5 attenuates the malignant growth and enhances the sensitivity of gastric cancer cells to 5‑FU chemotherapy by blocking the carcinogenic effect of YY1

Gastric cancer (GC) is one of the commonest malignant tumors of the digestive system, characterized by high morbidity and mortality rates. It has been reported that NOD like receptor (NLR) family, CARD domain containing 5 (NLRC5) serves an important role in the occurrence and development of GC. Therefore, the current study aimed to investigate the role of NLRC5 in GC. The mRNA and protein expression levels of NLRC5 in GC cell lines were determined by reverse transcription-quantitative PCR and western blot analysis, respectively. Additionally, following NLRC5 knockdown, cell proliferation, invasion and migration were evaluated using Cell Counting Kit 8, colony formation, wound healing and Transwell assays, and western blot analysis. The NLRC and Yin Yang 1 (YY1) expression in the AGS cells with 5-FU resistance were detected by western blotting. The sensitivity of GC cells to 5-fluorouracil (5-FU) was detected by flow cytometry and western blot analysis. Additionally, the binding capacity of YY1 on NLRC5 promoter was predicted using JASPAR database and it was further verified by chromatin immunoprecipitation and luciferase reporter assays. Finally, to elucidate the mechanism underlying the effect of NLRC5 on GC, YY1 was overexpressed and NLRC5 was silenced in GC cell lines. The results showed that NLRC5 was abnormally upregulated in GC cells. In addition, NLRC5 knockdown significantly attenuated the proliferation, invasion and migration abilities of GC cells, while it enhanced the sensitivity of GC cells to 5-FU. The above effects were regulated by the YY1 transcription factor. Overall, the results of the present study indicated that NLRC5 silencing could reduce the malignant growth and enhance the sensitivity of GC cells to 5-FU chemotherapy via inhibiting the carcinogenic effect of YY1.

NLR family CARD domain containing 5 promotes hypoxia-induced cancer progress and carboplatin resistance by activating PI3K/AKT via carcinoembryonic antigen related cell adhesion molecule 1 in non-small cell lung cancer

It is well known that non-small cell lung cancer (NSCLC) is a malignant tumor with high incidence in the world. We aimed to clarify a possible target and identify its precise molecular biological mechanism in NSCLC. NLR family CARD domain containing 5 (NLRC5) is widely expressed in tissues and exerts a vital role in anti-tumor immunity. We determined NLRC5 expression by RT-qPCR and western blot assay. The role of NLRC5 in the development of NSCLC was assessed by a loss-of-function assay. CCK-8, Annexin-V-FITC/PI Apoptosis Detection Kit, Transwell, and wound healing assays were used to determine the cell functions. Drug resistance-related proteins were analyzed by western blot assay. Furthermore, the modulation of NLRC5 on carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) expression and subsequent PI3K/AKT signaling was assessed. In this study, a hyper-expression of NLRC5 was found in NSCLC tissues and cell lines. Knockdown of NLRC5 suppressed cell viability, invasion, and migration, and furthermore promoted cell apoptosis in NSCLC cells. Moreover, under normoxia or hypoxia treatment, the upregulation of NLRC5 was related to carboplatin resistance. NLRC5 silencing increased carboplatin-resistant cell chemosensitivity, as evidenced by the increase in the cell inhibition rate and decrease in drug resistance-related protein expression. Mechanistically, NLRC5 knockdown inhibited the expression of CEACAM1 and subsequently blocked the PI3K/AKT signaling pathway. In conclusion, NLRC5 promotes the malignant biological behaviors of NSCLC cells by activating the PI3K/AKT signaling pathway via the regulation of CEACAM1 expression under normoxia and hypoxia.

Bone Marrow Mesenchymal Stem Cell (BMSC)-Exosomes Overexpressing miR-141 Inhibit the Malignant Biological Behavior of Glioma Cells via Wnt Signaling

Our study explores whether BMSC-exosomes overexpressing miR-141 can regulate Wnt signal to inhibit the malignant biological behavior of glioma cells. Thirty healthy mice were selected to construct a glioma mouse model and assigned randomly into the control group, miR-141 NC group, and miR-141 mimic group followed by analysis of cell proliferation, apoptosis, protein expression and mRNA expression by MTT method, flow cytometry, Western blot and RT-PCR methods. Compared with the other two groups, miR-141 mimic group showed reduced number of cell proliferation at 24 h and 48 h, decreased cell migration and invasion ability, and the increased cell apoptosis rate (P < 0.05). In miR-141 mimic group, the protein expression of miR-141 was the highest, while the protein expression of β-catenin, survivin and c-myc was the lowest (P < 0.05). In conclusion, BMSC-exosomes overexpressing miR-141 can inhibit the malignant biological behavior of GC cells possibly by inhibiting the activation of Wnt signaling pathway.

LncRNA GIHCG promoted the proliferation and migration of renal cell carcinoma through regulating miR-499a-5p/XIAP axis

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LncRNA GIHCG facilitated the proliferation and migration while suppressed apoptosis of RCC cells.

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LncRNA GIHCG directly sponged miR-499a-5p and down-regulated its expression.

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MiR-499a-5p negatively regulated XIAP expression.

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LncRNA GIHCG knockdown inhibited the growth and metastasis of RCC in nude mice.

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LncRNA GIHCG contributed to the development of RCC through miR-499a-5p/XIAP axis.

Background

Our previous study demonstrated that lncRNA GIHCG is upregulated in renal cell carcinoma (RCC) and that knockdown of lncRNA GIHCG suppresses the proliferation and migration of RCC cells. However, the mechanism of lncRNA GIHCG in RCC needs further exploration.

Methods

The proliferation, cell cycle, migration, and apoptosis of RCC cells were tested using CCK-8, flow cytometry, wound healing and Annexin-V/-FITC/PI flow cytometry assays, respectively. Dual-luciferase reporter and RNA pull-down or RNA immunoprecipitation assays (RIPs) were performed to analyze the interactions among lncRNA GIHCG, miR-499a-5p and XIAP. A tumour xenograft study was conducted to verify the function of lncRNA GIHCG in RCC development in vivo.

Results

Knockdown of lncRNA GIHCG inhibited cell proliferation and migration and induced G0/G1 arrest while promoting apoptosis. Overexpression of lncRNA GIHCG led to the opposite results. LncRNA GIHCG sponged miR-499a-5p and downregulated its expression in RCC cells. MiR-499a-5p overexpression suppressed RCC cell growth. MiR-499a-5p targeted XIAP and inhibited its expression. LncRNA GIHCG knockdown reduced the growth of tumour xenografts in vivo and the expression of XIAP while increasing miR-499a-5p levels.

Conclusion

LncRNA GIHCG accelerated the development of RCC by targeting miR-499a-5p and increasing XIAP levels.

The up-regulation of LRIG1 expression inhibits the proliferation, apoptosis and invasion of glioma cells

OBJECTIVE

To illustrate the role of LRIG1 in regulating the Notch signaling pathway and glioma cell proliferation, apoptosis and invasion.

METHODS

The glioma cells (U373) were divided into control group, NC group and LRIG1 group. After transfection, the CCK-8 assay, Transwell assay, and Flow cytometry were used to explore the biological function of LRIG1 in glioma cells. At the end, Western blot was used to detect the expression of LRIG1, Notch1, Hes1, Bcl-2, and Bax.

RESULTS

The LRIG1 expression in U373 cells was remarkably lower than that in normal glial cells (P=0.019). The LRIG1 expression in the LRIG1 group was successfully increased when compared with that in the control group (P=0.004). The cell viability of the LRIG1 group was significantly lower than that of the NC group and control group at 24 h, 48 h, and 72 h (P=0.040, 0.025; P=0.041, 0.041; P=0.035, 0.035) respectively. Increased LRIG1 expression level in glioma cells strongly inhibits cell migration in transwell experiment. Flow cytometry results indicated that the apoptosis rate of the LRIG1 group was critically higher than that of the NC group and control group (P=0.003; P=0.003). According to results of Western blot, the expression levels of Notch1, Hes1, Hes5, and Jagged1 in LRIG1 group were dramatically higher than that in NC group and control group (P=0.006, 0.013; P=0.025, 0.026; P=0.001, 0.004; P=0.025, 0.027; P=0.029, 0.021) reespectively. While Bax expression in LRIG1 group was lower than that of NC group and control group (P=0.018, 0.021).

CONCLUSION

The up-regulation of LRIG1 can inhibit the proliferation and migration of glioma cells and promote apoptosis by regulating the Notch signaling pathway.

Non-Coding RNAs and Brain Tumors: Insights Into Their Roles in Apoptosis

A major terrifying ailment afflicting the humans throughout the world is brain tumor, which causes a lot of mortality among pediatric and adult solid tumors. Several major barriers to the treatment and diagnosis of the brain tumors are the specific micro-environmental and cell-intrinsic features of neural tissues. Absence of the nutrients and hypoxia trigger the cells' mortality in the core of the tumors of humans' brains: however, type of the cells' mortality, including apoptosis or necrosis, has been not found obviously. Current studies have emphasized the non-coding RNAs (ncRNAs) since their crucial impacts on carcinogenesis have been discovered. Several investigations suggest the essential contribution of such molecules in the development of brain tumors and the respective roles in apoptosis. Herein, we summarize the apoptosis-related non-coding RNAs in brain tumors.

Molecular Mechanisms of lncRNAs in the Dependent Regulation of Cancer and Their Potential Therapeutic Use

Deep whole genome and transcriptome sequencing have highlighted the importance of an emerging class of non-coding RNA longer than 200 nucleotides (i.e., long non-coding RNAs (lncRNAs)) that are involved in multiple cellular processes such as cell differentiation, embryonic development, and tissue homeostasis. Cancer is a prime example derived from a loss of homeostasis, primarily caused by genetic alterations both in the genomic and epigenetic landscape, which results in deregulation of the gene networks. Deregulation of the expression of many lncRNAs in samples, tissues or patients has been pointed out as a molecular regulator in carcinogenesis, with them acting as oncogenes or tumor suppressor genes. Herein, we summarize the distinct molecular regulatory mechanisms described in literature in which lncRNAs modulate carcinogenesis, emphasizing epigenetic and genetic alterations in particular. Furthermore, we also reviewed the current strategies used to block lncRNA oncogenic functions and their usefulness as potential therapeutic targets in several carcinomas.

EGR1 modulated LncRNA HNF1A-AS1 drives glioblastoma progression via miR-22-3p/ENO1 axis

Accumulating evidences revealed that long noncoding RNAs (lncRNAs) have been participated in cancer malignant progression, including glioblastoma multiforme (GBM). Despite much studies have found the precise biological role in the regulatory mechanisms of GBM, however the molecular mechanisms, particularly upstream mechanisms still need further elucidated. RT-QPCR, cell transfection, western blotting and bioinformatic analysis were executed to detect the expression of EGR1, HNF1A-AS1, miR-22-3p and ENO1 in GBM. Cell proliferation assay, colony formation assay, wound healing, migration and invasion assays were performed to detect the malignant characters of GBM cells. The molecular regulation mechanism was confirmed by luciferase reporter assay, ChIP and RIP. Finally, orthotopic mouse models were established to examine the effect of HNF1A-AS1 in vivo. In the current study, we analyzed clinical samples to show that the HNF1A-AS1 expression is upregulated and associated with poor patient survival in GBM. Functional studies revealed that HNF1A-AS1 knockdown markedly inhibits malignant phenotypes of GBM cells, whereas overexpression of HNF1A-AS1 exerts opposite effect. Mechanistically, the transcription factor EGR1 forced the HNF1A-AS1 expression by directly binding the promoter region of HNF1A-AS1. Furthermore, combined bioinformatics analysis with our mechanistic work, using luciferase reporter assays and RIP, we first demonstrated that HNF1A-AS1 functions as a competing endogenous RNA (ceRNA) with miR-22-3p to regulate ENO1 expression in GBM cells. HNF1A-AS1 directly binds to miR-22-3p and significantly inhibits miR-22-3p expression, while ENO1 expression was increased. miR-22-3p inhibitor offsets the HNF1A-AS1 silencing induced suppression in malignant behaviors of GBM cells. ENO1 was verified as a direct target of miR-22-3p and its expression levels was negatively with the prognosis in GBM patients. Taken together, our study illuminated the definite mechanism of HNF1A-AS1 in promoting GBM malignancy, and provided a novel therapeutic target for further clinical application.

Regulatory interplay between microRNAs and WNT pathway in glioma

Glioma is one of the most common neoplasms of the central nervous system with a poor survival. Due to the obstacles in treating this disease, a part of recent studies mainly focuses on identifying the underlying molecular mechanisms that contribute to its malignancy. Altering microRNAs (miRNAs) expression pattern has been identified obviously in many cancers. Through regulating various targets and signaling pathways, miRNAs play a pivotal role in cancer progression. As one of the essential signaling pathways, WNT pathway is dysregulated in many cancers, and a growing body of evidence emphasis its dysregulation in glioma. Herein, we provide a comprehensive review of miRNAs involved in WNT pathway in glioma. Moreover, we show the interplay between miRNAs and WNT pathway in regulating different processes such as proliferation, invasion, migration, radio/chemotherapy resistance, and epithelial-mesenchymal-transition. Then, we introduce several drugs and treatments against glioma, which their effects are mediated through the interplay of WNT pathway and miRNAs.

SCAMP2/5 as diagnostic and prognostic markers for acute myeloid leukemia

The secretory carrier-associated membrane proteins (SCAMPs) are associated with the development of multiple human cancers. The role of SCAMPs in acute myeloid leukemia (AML), however, remains to be identified. In the present study, we explored expression patterns and prognostic value of SCAMPs and network analysis of SCAMPs-related signaling pathways in AML using Oncomine, GEPIA, cBioPortal, LinkedOmics, DAVID and Metascape databases. Genetic alteration analysis revealed that the mutation rate of SCAMP genes was below 1% (9/1272) in AML, and there was no significant correlation between SCAMPs gene mutation and AML prognosis. However, the SCAMP2/5 mRNA levels were significantly higher in AML patients than in healthy controls. Moreover, high mRNA expressions of SCAMP2/4/5 were associated with poor overall survival, which might be due to that SCAMP2/4/5 and their co-expressed genes were associated with multiple pathways related to tumorigenesis and progression, including human T-cell leukemia virus 1 infection, acute myeloid leukemia, mTOR and NF-kappa B signaling pathways. These results suggest that SCAMP2/4/5 are potential prognostic markers for AML, and that SCAMP2 and SCAMP5 individually or in combination may be used as diagnostic markers for AML.

NLRC5: A Potential Target for Central Nervous System Disorders

Nucleotide oligomerization domain-like receptors (NLRs), a class of pattern recognition receptors, participate in the host’s first line of defense against invading pathogenic microorganisms. NLR family caspase recruitment domain containing 5 (NLRC5) is the largest member of the NLR family and has been shown to play an important role in inflammatory processes, angiogenesis, immunity, and apoptosis by regulating the nuclear factor-κB, type I interferon, and inflammasome signaling pathways, as well as the expression of major histocompatibility complex I genes. Recent studies have found that NLRC5 is also associated with neuronal development and central nervous system (CNS) diseases, such as CNS infection, cerebral ischemia/reperfusion injury, glioma, multiple sclerosis, and epilepsy. This review summarizes the research progress in the structure, expression, and biological characteristics of NLRC5 and its relationship with the CNS.

LncRNA-NNT-AS1 contributes to the progression of glioma by miR-582-5p/EZH2 axis

Increasing studies have shown that long non-coding RNAs (lncRNAs) had crucial regulatory roles in many diseases. Nevertheless, the biological relevance and mechanisms of the NNT-AS1 in gliom remain poorly understood. In the present study, NNT-AS1 expression was up-regulated in the glioma cell lines. Functional assays demonstrated that depletion of NNT-AS1 could notably suppress the proliferation, migration, invasion and EMT of U87MG and A172 cells. In addition, miR-582-5p was predicted to be a target of NNT-AS1 and EZH2 was predicted to be a target of miR-582-5p by bioinformatics software, which was further confirmed by luciferase reporter assay. Additionally, results of recue assays proofed that NNT-AS1/miR-582-5p/EZH2 axis aggravated the malignant behaviors of glioma. Ultimately, our findings revealed that NNT-AS1 contributes to progression via targeting miR-582-5p/EZH2 axis, revealing NNT-AS1 as a latent effective target for the diagnosis and treatment of glioma patients.

GJA1 rs2071165 A > G Variant Increased Gastric Cancer Risk in Females of Northwest China: A Case-Control Study

Gastric cancer (GC) is one of the most common malignancies, and its incidence rates vary widely between men and women. Previous studies have suggested that connexin 43 (Cx43, encoded by gap junction protein alpha 1 (GJA1)) and secretory carrier membrane protein 1 (SCAMP1) are key functional proteins in tumors. Herein, the association between GJA1 and SCAMP1 polymorphisms and GC susceptibility and prognosis was evaluated. A total of three single-nucleotide polymorphisms among 681GC patients and 756 controls were tested using the Agena MassARRAY RS1000 system, including GJA1 rs2071165, SCAMP1 rs4530741, and SCAMP1 rs6874309. The strength of the association with GC risk was assessed by the odds ratios (ORs) and 95% confidence intervals (CIs) generated from the logistic regression model. Kaplan–Meier curve, long-rank tests, and a multivariate Cox proportional hazard model were used for prognosis analysis. The expression of GJA1 was assessed by immunohistochemistry. The GJA1 rs2071165 AA/AG genotype significantly increased the risk of GC in the female Chinese population (OR = 1.55, 95% CI = 1.03–2.32, p=0.034). Furthermore, the risk effect of GJA1 rs2071165 was more evident in the subgroups of female patients with GC, stratified by age, clinical stage, tumor size, and recurrence/metastasis. However, no obvious differences in Cx43 expression in GC tissues were observed between males and females. Furthermore, no significant association between SCAMP1 rs4530741 and rs6874309 polymorphisms and GC risk or prognosis was observed. In conclusion, this study suggests for the first time that the GJA1 rs2071165 polymorphism is associated with increased GC risk in females, revealing a potential new clinical marker for assessing GC risk in females.

Upregulation of miR-499a-5p Decreases Cerebral Ischemia/Reperfusion Injury by Targeting PDCD4

MiR-499a-5p was significantly downregulated in degenerative tissues and correlated with apoptosis. Nonetheless, the biological function of miR-499a-5p in acute ischemic stroke has been still unclear. In this study, we found that the plasma levels of miR-499a-5p were significantly downregulated in 64 ischemic stroke patients and negatively correlated with the National Institutes of Health Stroke Scale score. Then, we constructed cerebral ischemia/reperfusion (I/R) injury in rats after middle cerebral artery occlusion and subsequent reperfusion and oxygen-glucose deprivation and reoxygenation (OGD/R)-treated SH-SY5Y cell model. Transfection with miR-499a-5p mimic was accomplished by intracerebroventricular injection in the in vivo I/R injury model. We further found that miR-499a-5p overexpression decreased infarct volumes and cell apoptosis in the in vivo I/R stroke model using TTC and TUNEL staining. PDCD4 was a direct target of miR-499a-5p by luciferase report assay and Western blotting. Knockdown of PDCD4 reduced the infarct damage and cortical neuron apoptosis caused by I/R injury. MiR-499a-5p exerted neuroprotective roles mainly through inhibiting PDCD4-mediated apoptosis by CCK-8 assay, LDH release assay, and flow cytometry analysis. These findings suggest that miR-499a-5p might represent a novel target that regulates brain injury by inhibiting PDCD4-mediating apoptosis.

Non-coding RNAs related to angiogenesis in gynecological cancer

Gynecological cancer affects the female reproductive system, including ovarian, uterine, endometrial, cervical, vulvar, and vaginal tumors. Non-coding RNAs (ncRNAs), and in particular microRNAs, function as regulatory molecules, which can control gene expression in a post-transcriptional manner. Normal physiological processes like cellular proliferation, differentiation, and apoptosis, and pathological processes such as oncogenesis and metastasis are regulated by microRNAs. Numerous reports have shown a direct role of microRNAs in the modulation of angiogenesis in gynecological cancer, via targeting pro-angiogenic factors and signaling pathways. Understanding the molecular mechanism involved in the regulation of angiogenesis by microRNAs may lead to new treatment options. Recently the regulatory role of some long non-coding RNAs in gynecological cancer has also been explored, but the information on this function is more limited. The aim of this article is to explore the pathways responsible for angiogenesis, and to what extent ncRNAs may be employed as biomarkers or therapeutic targets in gynecological cancer.

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

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

Overexpression of long non-coding RNA XIST promotes IL-1β-induced degeneration of nucleus pulposus cells through targeting miR-499a-5p

BACKGROUND

Long non-coding RNA X-interactive specific transcript (XIST) is implicated in many diseases. However, its role and interaction with microRNA (miR)-499a-5p in intervertebral disc degeneration (IDD) remained unclear.

METHODS

Nucleus pulposus (NP) tissue samples were collected and nucleus pulposus cells (NPCs) were isolated for Interleukin-1β (IL-1β) treatment and identification. XIST and miR-499a-5p expressions in the tissue were measured with quantitative real-time polymerase chain reaction (qRT-PCR). After IL-1β treatment, NPC apoptosis was detected by flow cytometry. The potential binding sites of XIST and miR-499a-5p were predicted by starBase and confirmed by dual-luciferase reporter assay. Relative expressions of tissue inhibitor of metalloproteinases-3 (TIMP-3), Matrix metalloproteinases-3 (MMP-3), MMP-13, Collagen II, Aggrecan and apoptosis-related proteins (Bcl-2 associated X protein, Bax; B-cell lymphoma 2, Bcl-2; cleaved caspase-3) were measured by qRT-PCR and Western blot as needed.

RESULTS

XIST expression was upregulated in the NP tissues of patients with IDD, and IL-1β treatment resulted in a degradation of NPCs. Overexpressed XIST promoted the effects of IL-1β on increasing NPC apoptosis and expressions of XIST, MMP-3, MMP-13, Bax and Cleaved caspase-3, but down-regulated TIMP-3, Collagen II, Aggrecan and Bcl-2 expressions. Silencing XIST, however, showed the opposite effects to its overexpression. MiR-499a-5p expression was downregulated in NP tissues of IDD patients and could bind with XIST, while its upregulation reversed the effects of overexpressed XIST in the IL-1β-treated NPCs.

CONCLUSION

Overexpressed XIST caused NPC degeneration through promoting apoptosis and extracellular matrix degradation of IL-1β-treated NPCs through targeting miR-499a-5p, and therefore can serve as a potential treatment for IDD.

The MHC Class-I Transactivator NLRC5: Implications to Cancer Immunology and Potential Applications to Cancer Immunotherapy

The immune system constantly monitors the emergence of cancerous cells and eliminates them. CD8⁺ cytotoxic T lymphocytes (CTLs), which kill tumor cells and provide antitumor immunity, select their targets by recognizing tumor antigenic peptides presented by MHC class-I (MHC-I) molecules. Cancer cells circumvent immune surveillance using diverse strategies. A key mechanism of cancer immune evasion is downregulation of MHC-I and key proteins of the antigen processing and presentation machinery (APM). Even though impaired MHC-I expression in cancers is well-known, reversing the MHC-I defects remains the least advanced area of tumor immunology. The discoveries that NLRC5 is the key transcriptional activator of MHC-I and APM genes, and genetic lesions and epigenetic modifications of NLRC5 are the most common cause of MHC-I defects in cancers, have raised the hopes for restoring MHC-I expression. Here, we provide an overview of cancer immunity mediated by CD8⁺ T cells and the functions of NLRC5 in MHC-I antigen presentation pathways. We describe the impressive advances made in understanding the regulation of NLRC5 expression, the data supporting the antitumor functions of NLRC5 and a few reports that argue for a pro-tumorigenic role. Finally, we explore the possible avenues of exploiting NLRC5 for cancer immunotherapy.

MiRNA-128-3p Restrains Malignant Melanoma Cell Malignancy by Targeting NTRK3

The functions of non-coding RNA, including microRNA (miRNA), have attracted considerable attention in the field of oncology, In this report, we examined the roles and molecular mechanisms of miR-128-3p, as related to the biological behaviors of malignant melanoma (MM). We found that miR-128-3p was expressed in low levels in these MM cells and may serve as a tumor suppressor by inhibiting proliferation, migration, and invasion, as well as inducing apoptosis in these MM cells. Moreover, neurotrophin receptor 3 (NTRK3), which serves as an oncogene that can enhance malignant behaviors of MM cells, was up-regulated in MM cells. Our current survey disclosed a complementary binding between miR-128-3p and the NTRK3 3' untranslated regions (3'-UTR), while luciferase activities of NTRK3 3'-UTR were restrained by miR-128-3p in 293T cells. The effects of pre-miR-128-3p and sh-NTRK3 as well as anti-miR-128-3p and NTRK3(+) appeared to function synergistically in producing malignant progression. Moreover, there were possible to have counteracted effects for pre-miR-128-3p and NTRK3(+) in malignant progression. These findings established that miR-128-3p can function as a tumor suppressor by inhibiting carcinogenesis of the oncogene, NTRK3. Collectively, miR-128-3p and NTRK3 genes participate in modulating the malignant behavior of MM, and may represent new therapeutic targets for MM.

Expression and prognostic analyses of SCAMPs in pancreatic adenocarcinoma

Due to the difficulties in early diagnosis of pancreatic adenocarcinoma (PAAD), many patients fail to receive optimal therapeutic regimens. The Secretory-Carrier-Membrane-Proteins (SCAMPs) are known to be dysregulated in a range of human diseases due to their characterized roles in mammalian cell exocytosis inferred from their functions as integral membrane proteins. However, the expression and prognostic value of SCAMPs in PAAD is poorly characterized. We compared cancer vs. healthy tissue and found that the expression of SCAMPs1-4 was upregulated in PAAD compared to normal tissue. In contrast, SCAMP5 expression was downregulated in PAAD. Moreover, the expression of SCAMPs1-4 was enhanced in PAAD cell lines according to Cancer Cell Line public database. Furthermore, the HPA, GEPIA databases and immunohistochemical analysis from 238 patients suggested that the loss of SCAMP1 led to improved overall survival (OS), whilst lower SCAMP5 levels led to a poorer OS. The univariate and multivariate analysis showed that SCAMP1 and SCAMP5 expression were independent prognostic factors of PAAD. In addition, the cBioPortal for Cancer Genomics, LinkedOmics datasets, and the GEPIA were used to identify the co-expression genes of SCAMP1,5 and the correlation between SCAMPs members. We conclude that SCAMPs 1 and 5 significantly represent promising diagnosis and prognostic biomarkers.

LncRNAs in cancer: Regulatory and therapeutic implications

Long noncoding RNAs (lncRNAs) comprise a class of RNAs that do not code for proteins but are critical in regulating diverse cellular processes and maintaining cell function. In doing so, they have, in recent years, added a potentially new and significant layer of biological regulation. These are more than 200 nucleotides in length and are implicated in a range of diseases and therefore have emerged as potential tools for possible therapeutic intervention. For a disease as complex as cancer, emerging technologies suggest the presence of mutations on genomic loci that do not encode proteins, but give rise to lncRNAs. Aberrant signatures of lncRNAs are now a consistent feature of almost all types of cancers and their associated complications. Analysis and characterisation of functional pathways that lncRNAs are involved with suggest that lncRNAs interact with the chromatin, the protein or with the RNA to demonstrate their cellular effects to modulate proliferation, migration, differentiation, apoptosis and cell death. This review summarizes the current knowledge of lncRNAs, their implications in diverse types of cancer and their possible therapeutic utility.

Linc00475 promotes the progression of glioma by regulating the miR-141-3p/YAP1 axis

Glioma is the most prevalent and lethal primary brain tumour. Abundant long non‐coding RNAs ( lncRNAs) are aberrant and play crucial roles in the oncogenesis of glioma. The exact functions of linc00475 in glioma remain blurred. Here, we analysed the expression levels of linc00475 by qRT‐PCR and discovered that linc00475 was up‐regulated in glioma and predicted a poor prognosis in patients with glioma. Besides, inhibiting linc00475 restrained the progression of glioma in vitro and in vivo. Further experiments confirmed that linc00475 regulated the progression of glioma by acting as a sponge for miR‐141‐3p. Moreover, we detected the binding sites of linc00475 and miR‐141‐3p, the YAP1‐ 3′UTR and miR‐141‐3p by luciferase reporters. The rescue assays confirmed that inhibiting linc00475 restrained the progression of glioma through the miR‐141‐3p/YAP1 pathway. Collectively, our research demonstrates the key roles of linc00475 in glioma, which could be a promising therapeutic target.

LncRNA TMPO-AS1 Promotes Proliferation and Invasion by Sponging miR-383-5p in Glioma Cells

Purpose

Glioma is one of the most common malignant tumors affecting human health. Long non-coding RNA (lncRNA) TMPO-AS1 participates in the pathogenesis of various cancers. However, the role of lncRNA TMPO-AS1 in glioma remains largely unknown. This study aims to uncover the role of TMPO-AS1 and explore its potential mechanism in glioma.

Methods

Expression levels of TMPO-AS1 and miR-383-5p in glioma cell lines were measured by real-time quantitative PCR (RT-qPCR). CCK-8, colony formation, wound-healing, and Transwell assays were conducted to determine cell proliferation, migration and invasion abilities, respectively. Western blotting was applied to detect the expression of corresponding proteins. Immunofluorescence assay was performed to measure the expression of Ki67. The binding condition between TMPO-AS1 and miR-383-5p was verified by dual-luciferase reporter assay.

Results

We found that TMPO-AS1 was up-regulated while miR-383-5p was down-regulated in glioma cell lines, and knockdown of TMPO-AS1 significantly suppressed glioma cell proliferation, migration and invasion abilities. miR-383-5p was demonstrated to be a direct target of TMPO-AS1. Besides, inhibition of miR-383-5p abolished the effects of TMPO-AS1 knockdown on glioma cells.

Conclusion

In summary, our study revealed that inhibition of lncRNA TMPO-AS1 could suppress glioma progression through targeting miR-383-5p. TMPO-AS1 might be used as a therapeutic target for glioma treatment.

lncRNA CTBP1-AS2 promotes proliferation and migration of glioma by modulating miR-370-3p-Wnt7a-mediated epithelial-mesenchymal transition

Glioma is one of the most common and aggressive malignant primary brain tumors, with a poor 5-year survival rate. The long noncoding RNA (lncRNA) CTBP1-AS2 has been shown to be correlated with the prognosis of cancer, but the role of CTBP1-AS2 in glioma and its concrete mechanism is fully unknown. The clinical data and tissues of glioma patients were analyzed. Cell viability and migration assays were performed. Western blotting and qRT-PCR were adopted for investigation of target protein expressions. Double luciferase assay was used to investigate the interaction between different elements. The lncRNA CTBP1-AS2 had increased expression profiles in tumor tissues, which is associated with poor prognosis. In detail, CTBP1-AS2 knockdown decreased proliferation and migration phenotypes in both U87-MG and LN229 cells. Moreover, CTBP1-AS2 knockdown suppressed the key epithelial-mesenchymal transition (EMT) markers by downregulating Wnt7a-mediated signaling. Furthermore, miR-370-3p functioned as a link that could be absorbed by CTBP1-AS2, thus regulating Wnt7a expression. Lastly, the CTBP1-AS2-miR-370-3p-Wnt7a axis modulated EMT in glioma cells in vitro and in vivo. This study provides new insights that a novel lncRNA, CTBP1-AS2, regulates EMT of glioma by modulating the miR-370-3p-Wnt7a axis.

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.

Strategies to target long non-coding RNAs in cancer treatment: progress and challenges

Background

Long non-coding RNAs are important regulators of gene expression and diverse biological processes. Their aberrant expression contributes to a verity of diseases including cancer development and progression, providing them with great potential to be diagnostic and prognostic biomarkers and therapeutic targets. Therefore, they can have a key role in personalized cancer medicine.

This review aims at introducing possible strategies to target long ncRNAs therapeutically in cancer. Also, chemical modification of nucleic acid-based therapeutics to improve their pharmacological properties is explained. Then, approaches for the systematic delivery of reagents into the tumor cells or organs are briefly discussed, followed by describing obstacles to the expansion of the therapeutics.

Main text

Long ncRNAs function as oncogenes or tumor suppressors, whose activity can modulate all hallmarks of cancer. They are expressed in a very restricted spatial and temporal pattern and can be easily detected in the cells or biological fluids of patients. These properties make them excellent targets for the development of anticancer drugs. Targeting methods aim to attenuate oncogenic lncRNAs or interfere with lncRNA functions to prevent carcinogenesis. Numerous strategies including suppression of oncogenic long ncRNAs, alternation of their epigenetic effects, interfering with their function, restoration of downregulated or lost long ncRNAs, and recruitment of long ncRNAs regulatory elements and expression patterns are recommended for targeting long ncRNAs therapeutically in cancer. These approaches have shown inhibitory effects on malignancy. In this regard, proliferation, migration, and invasion of tumor cells have been inhibited and apoptosis has been induced in different cancer cells in vitro and in vivo. Downregulation of oncogenic long ncRNAs and upregulation of some growth factors (e.g., neurotrophic factor) have been achieved.

Conclusions

Targeting long non-coding RNAs therapeutically in cancer and efficient and safe delivery of the reagents have been rarely addressed. Only one clinical trial involving lncRNAs has been reported. Among different technologies, RNAi is the most commonly used and effective tool to target lncRNAs. However, other technologies need to be examined and further research is essential to put lncRNAs into clinical practice.

Long non-coding RNA EWSAT1 contributes to the proliferation and invasion of glioma by sponging miR-152-3p

Long non-coding RNAs (lncRNA) are a type of ncRNA with a length ranging from 200-1,000 nucleotides. Previous studies have confirmed that the lncRNA Ewing sarcoma associated transcript 1 (EWSAT1) exerts regulatory roles in cancer development and progression. However, its clinical significance in glioma remains unknown. In the present study, RNA-sequencing data from the Gene Expression Omnibus database and The Cancer Genome Atlas was explored to investigate the association between EWSAT1 expression and prognosis in patients with glioma. Increased EWSAT1 was associated with the presence of necrosis on magnetic resonance imaging scans in patients with glioma. Furthermore, knockdown of EWSAT1 was indicated to suppress the proliferative and invasive abilities of glioblastoma cell lines using Cell Counting Kit-8 and Transwell assays. Additionally, microRNA (miR)-152-3p was identified as a potential target of EWSAT1. The present study demonstrated that EWSAT1 interacted directly with miR-152-3p, and rescue experiments confirmed that EWSAT1 participated in glioma development by suppressing miR-152-3p. These results indicated that EWSAT1 is involved in the occurrence and progression of glioma, and may serve as a novel target and potential prognostic biomarker of glioma treatment.

Long Noncoding RNA SCAMP1 Targets miR-137/CXCL12 Axis to Boost Cell Invasion and Angiogenesis in Ovarian Cancer

Ovarian cancer (OC) is one of gynecological malignancies that seriously affects women's health. Mounting evidence demonstrated that long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and messenger RNAs (mRNAs) play important roles in various biological processes related to the pathogenesis of OC. This research aimed to investigate the regulatory mechanism of lncRNA SCAMP1/miR-137/CXCL12 (C-X-C motif chemokine ligand 12) axis on OC progression. In this study, we found that SCAMP1 was highly expressed in OC cells, which promoted OC cell invasion and angiogenesis. In addition, our research confirmed that SCAMP1 could bind with miR-137, and SCAMP1 sponged miR-137 to accelerate the progression of OC. We also observed that CXCL12 was a downstream target gene for miR-137, and miR-137 targeted CXCL12 to participate in the regulation of OC. Finally, through TCGA database, we found that SCAMP1 (or CXCL12) was upregulated as well as miR-137 was downregulated in OC tissues, and high (or low) level of them was associated with poor prognosis. miR-137 expression was negatively correlated with SCAMP1 (or CXCL12) expression, and SCAMP1 expression was positively correlated with CXCL12 expression in OC. In summary, our study clarified the role of SCAMP1/miR-137/CXCL12 axis in OC, and this finding may provide a potential therapeutic target of OC.

An upstream open reading frame regulates vasculogenic mimicry of glioma via ZNRD1-AS1/miR-499a-5p/ELF1/EMI1 pathway

Increasing evidence has suggested that gliomas can supply blood through vasculogenic mimicry. In this study, the expression and function of ZNRD1‐AS1‐144aa‐uORF (144aa‐uORF) and some non‐coding RNAs in gliomas were assessed. Real‐time quantitative PCR or Western blot was used to discover the expression of 144aa‐uORF, ZNRD1‐AS1, miR‐499a‐5p, ELF1 and EMI1 in gliomas. In addition, RIP and RNA pull‐down assays were applied to explore the interrelationship between 144aa‐uORF and ZNRD1‐AS1. The role of the 144aa‐uORF\ZNRD1‐AS1\miR‐499a‐5p\ELF1\EMI1 axis in vasculogenic mimicry formation of gliomas was analysed. This study illustrates the reduced expression of the 144aa‐uORF in glioma tissues and cells. Up‐regulation of 144aa‐uORF inhibits proliferation, migration, invasion and vasculogenic mimicry formation within glioma cells. The up‐regulated 144aa‐uORF can increase the degradation of ZNRD1‐AS1 through the nonsense‐mediated RNA decay (NMD) pathway. Knockdown of ZNRD1‐AS1 inhibits vasculogenic mimicry in glioma cells by modulating miR‐499a‐5p. At the same time, miR‐499a‐5p is down‐regulated and has a tumour‐suppressive effect in gliomas. In addition, ZNRD1‐AS1 serves as a competitive endogenous RNA (ceRNA) and regulates the expression of ELF1 by binding to miR‐499a‐5p. Notably, ELF1 binds to the promoter region of EMI1 and up‐regulates EMI1 expression, while simultaneously promoting vasculogenic mimicry in glioma cells. This study suggests that the 144aa‐uORF\ZNRD1‐AS1\miR‐499a‐5p\ELF1\EMI1 axis takes key part in regulating the formation of vasculogenic mimicry in gliomas and may provide a potential target for glioma treatment.

NLRC5: new cancer buster?

Recent decades, there is significant progress in understanding the mechanisms of tumor progression and immune evasion. The newly discovered protein NLRC5 is demonstrated to participate in regulating cancer immune escape through enhancing MHC class I genes expression in certain tumors. Nevertheless, increasing evidence has revealed that NLRC5 is up-regulated in some other tumors and promote tumor development and progression. The purpose of this review is to describe the role of NLRC5 in tumors and discuss whether NLRC5 can be a potential target in cancer treatment.

MT1JP inhibits glioma progression via negative regulation of miR-24

Long noncoding RNAs have been reported to be dysregulated and have pivotal roles in various human malignancies, including glioma. Previous studies revealed that metallothionein 1J (MT1JP) has important regulatory functions in the development of gastric cancer. However, the biological role and potential mechanism of MT1JP in glioma remain unknown. The present study suggested that MT1JP expression was significantly downregulated in glioma tissues and glioma cell lines, and the decreased expression of MT1JP was associated with glioma progression and poor survival of patients with glioma. Additionally, overexpression of MT1JP significantly inhibited the proliferation and invasion of glioma cells. Furthermore, it was revealed that MT1JP interacted with microRNA-24 (miR-24), which has previously been reported as an oncogene in glioma, negatively regulating its expression level. Rescue experiments revealed that the tumor suppressive functions of MT1JP may be mediated by the negative regulation of miR-24. Collectively, the data suggested that MT1JP inhibited the progression of glioma by negatively regulating miR-24 and may serve as a novel diagnostic biomarker and therapeutic target for glioma.

Long noncoding RNA FLVCR1-AS1 aggravates biological behaviors of glioma cells via targeting miR-4731-5p/E2F2 axis

Long noncoding RNAs (lncRNAs) display essential roles in cancer progression. FLVCR1-AS1 is a rarely investigated lncRNAs involved in various human cancers, such as hepatocellular carcinoma and lung cancer. However, its function in glioma has not been clarified. In our study, we found that FLVCR1-AS1 was highly expressed in glioma tissues and cell lines. And upregulation of FLVCR1-AS1 predicted poor prognosis in patients with glioma. Moreover, FLVCR1-AS1 knockdown inhibited proliferation, migration and invasion of glioma cells. Through bioinformatics analysis, we identified that FLVCR1-AS1 was a sponge for miR-4731-5p to upregulate E2F2 expression. Moreover, rescue assays indicated that FLVCR1-AS1 modulated E2F2 expression to participate in glioma progression. Altogether, our research demonstrates that the FLVCR1-AS1/miR-4731-5p/E2F2 axis is a novel signaling in glioma and may be a potential target for tumor therapy.

Knockdown of LncRNA SCAMP1 suppressed malignant biological behaviours of glioma cells via modulating miR-499a-5p/LMX1A/NLRC5 pathway

Dysregulation of long non‐coding RNAs (lncRNAs) confirm that it plays a crucial role in tumourigenesis and malignant progression of glioma. The present study demonstrated that LncRNA secretory carrier membrane protein 1 (SCAMP1) was up‐regulated and functioned as an oncogene in glioma cells. In addition, miR‐499a‐5p was down‐regulated meanwhile exerted tumour‐suppressive function in glioma cells. Subsequently, inhibition of SCAMP1 significantly restrained the cell proliferation, migration and invasion, as well as promoted apoptosis by acting as a molecular sponge of miR‐499a‐5p. Transcription factor LIM homeobox transcription factor 1, alpha (LMX1A) was overexpressed in glioma tissues and cells. Moreover, miR‐499a‐5p targeted LMX1A 3′‐UTR in a sequence‐specific manner. Hence, down‐regulation of SCAMP1 remarkably reduced the expression level of LMX1A, indicating that LMX1A participated in miR‐499a‐5p‐induced tumour‐suppressive effects on glioma cells. Furthermore, knockdown of LMX1A decreased NLR family, CARD domain containing 5 (NLRC5) mRNA and protein expression levels through directly binding to the NLRC5 promoter region. Down‐regulation of NLRC5 obviously inhibited malignant biological behaviours of glioma cells through attenuating the activity of Wnt/β‐catenin signalling pathway. In conclusion, our study clarifies that SCAMP1/miR‐499a‐5p/LMX1A/NLRC5 axis plays a critical role in modulating malignant progression of glioma cells, which provide a novel therapeutic strategy for glioma treatment.