Long non-coding RNA NORAD inhibition upregulates microRNA-323a-3p to suppress tumorigenesis and development of breast cancer through the PUM1/eIF2 axis

Construction of an immune-related prognostic signature and lncRNA-miRNA-mRNA ceRNA network in acute myeloid leukemia

The progression of acute myeloid leukemia (AML) is influenced by the immune microenvironment in the bone marrow and dysregulated intracellular competing endogenous RNA (ceRNA) networks. Our study utilized data from UCSC Xena, The Cancer Genome Atlas Program, the Gene Expression Omnibus, and the Immunology Database and Analysis Portal. Using Cox regression analysis, we identified an immune-related prognostic signature. Genomic analysis of prognostic messenger RNA (mRNA) was conducted through Gene Set Cancer Analysis (GSCA), and a prognostic ceRNA network was constructed using the Encyclopedia of RNA Interactomes. Correlations between signature mRNAs and immune cell infiltration, checkpoints, and drug sensitivity were assessed using R software, gene expression profiling interactive analysis (GEPIA), and CellMiner, respectively. Adhering to the ceRNA hypothesis, we established a potential long noncoding RNA (lncRNA)/microRNA (miRNA)/mRNA regulatory axis. Our findings pinpointed 9 immune-related prognostic mRNAs (KIR2DL1, CSRP1, APOBEC3G, CKLF, PLXNC1, PNOC, ANGPT1, IL1R2, and IL3RA). GSCA analysis revealed the impact of copy number variations and methylation on AML. The ceRNA network comprised 14 prognostic differentially expressed lncRNAs (DE-lncRNAs), 6 prognostic DE-miRNAs, and 3 prognostic immune-related DE-mRNAs. Correlation analyses linked these mRNAs' expression to 22 immune cell types and 6 immune checkpoints, with potential sensitivity to 27 antitumor drugs. Finally, we identified a potential LINC00963/hsa-miR-431-5p/CSRP1 axis. This study offers innovative insights for AML diagnosis and treatment through a novel immune-related signature and ceRNA axis. Identified novel biomarkers, including 2 mRNAs (CKLF, PNOC), 1 miRNA (hsa-miR-323a-3p), and 10 lncRNAs (SNHG25, LINC01857, AL390728.6, AC127024.5, Z83843.1, AP002884.1, AC007038.1, AC112512, AC020659.1, AC005921.3) present promising candidates as potential targets for precision medicine, contributing to the ongoing advancements in the field.

COP9 signalosome component CSN-5 stabilizes PUF proteins FBF-1 and FBF-2 in Caenorhabditis elegans germline stem and progenitor cells

RNA-binding proteins FBF-1 and FBF-2 (FBFs) are required for germline stem cell maintenance and the sperm/oocyte switch in Caenorhabditis elegans, although the mechanisms controlling FBF protein levels remain unknown. We identified an interaction between both FBFs and CSN-5), a component of the constitutive photomorphogenesis 9 (COP9) signalosome best known for its role in regulating protein degradation. Here, we find that the Mpr1/Pad1 N-terminal metalloprotease domain of CSN-5 interacts with the Pumilio and FBF RNA-binding domain of FBFs and the interaction is conserved for human homologs CSN5 and PUM1. The interaction between FBF-2 and CSN-5 can be detected in vivo by proximity ligation. csn-5 mutation results in the destabilization of FBF proteins, which may explain previously observed decrease in the numbers of germline stem and progenitor cells, and disruption of oogenesis. The loss of csn-5 does not decrease the levels of a related PUF protein PUF-3, and csn-5(lf) phenotype is not enhanced by fbf-1/2 knockdown, suggesting that the effect is specific to FBFs. The effect of csn-5 on oogenesis is largely independent of the COP9 signalosome and is cell autonomous. Surprisingly, the regulation of FBF protein levels involves a combination of COP9-dependent and COP9-independent mechanisms differentially affecting FBF-1 and FBF-2. This work supports a previously unappreciated role for CSN-5 in the stabilization of germline stem cell regulatory proteins FBF-1 and FBF-2.

Role of ferroptosis and ferroptosis-related long non'coding RNA in breast cancer

Ferroptosis, a therapeutic strategy for tumours, is a regulated cell death characterised by the increased accumulation of iron-dependent lipid peroxides (LPO). Tumour-associated long non-coding RNAs (lncRNAs), when combined with traditional anti-cancer medicines or radiotherapy, can improve efficacy and decrease mortality in cancer. Investigating the role of ferroptosis-related lncRNAs may help strategise new therapeutic options for breast cancer (BC). Herein, we briefly discuss the genes and pathways of ferroptosis involved in iron and reactive oxygen species (ROS) metabolism, including the XC-/GSH/GPX4 system, ACSL4/LPCAT3/15-LOX and FSP1/CoQ10/NAD(P)H pathways, and investigate the correlation between ferroptosis and LncRNA in BC to determine possible biomarkers related to ferroptosis.

Suppression of circular RNA serum and glucocorticoid-induced kinase 1 elevates antioxidant molecules and angiogenesis in trophoblast cells to attenuate preeclampsia via microRNA-508-3p to target and restrain PUM homolog 1

AIM

Preeclampsia (PE) is a pregnancy-specific syndrome characterized by hypertension and proteinuria. Recently, multiple circular RNAs (circRNAs) were considered latent clinical diagnostic markers or therapeutic targets. This study was to explore the impact of circRNA serum and glucocorticoid-induced kinase 1 (SGK1) on PE via influencing the microRNA (miR)-508-3p/PUM homolog 1 (PUM1) axis.

METHODS

Placental tissues of 34 pregnant women with PE and 34 normal pregnant women were collected to measure circRNA SGK1 (circSGK1), miR-508-3p, and PUM1. Human placental trophoblasts HTR-8/SVneo were transfected with plasmids, thereafter to observe proliferation, migration, invasion, and apoptosis, analyze antioxidant molecules Troxerutin (TXN), Glutamate-cysteine ligase catalytic subunit (GCLC), NAD (P) H-quinone oxidoreductase 1 (NQO1), and determine angiogenesis. After the construction of the PE rat model, antioxidant molecules TXN, GCLC, and NQO1, vascular-associated factor vascular endothelial growth factor A (VEGF-A), and histopathological conditions were tested. Examination of the binding of circSGK1 and miR-508-3p with PUM1 was performed.

RESULTS

Our data showed that circSGK1 expression was elevated in the placenta of patients with PE. Silenced circSGK1 or elevated miR-508-3p promoted the growth and antioxidant molecules and angiogenesis in trophoblast cells; CircSGK1 combined with miR-508-3p, and miR-508-3p targeted PUM1.

CONCLUSIONS

In summary, suppression of circSGK1 augments antioxidant molecules and angiogenesis in trophoblast cells to attenuate PE via miR-508-3p to target PUM1.

Non-coding RNAs and angiogenesis in cardiovascular diseases: a comprehensive review

Non-coding RNAs (ncRNAs) have key roles in the etiology of many illnesses, including heart failure, myocardial infarction, stroke, and in physiological processes like angiogenesis. In transcriptional regulatory circuits that control heart growth, signaling, and stress response, as well as remodeling in cardiac disease, ncRNAs have become important players. Studies on ncRNAs and cardiovascular disease have made great progress recently. Here, we go through the functions of non-coding RNAs (ncRNAs) like circular RNAs (circRNAs), and microRNAs (miRNAs) as well as long non-coding RNAs (lncRNAs) in modulating cardiovascular disorders.

Exosome-mediated circGMPS facilitates the development of gastric cancer cells through miR-144-3p/PUM1

In recent years, gastric cancer (GC) is still one of the major public health burdens in the world. It is reported that exosome circular RNA (circRNA) is involved in the GC progression. However, the function and potential mechanism of circGMPS in GC remains unclear and needs further exploration. In this study, we isolated and identified exosomes from serum by TEM, NTA analysis and Western blot. RNA expression was evaluated by qRT-PCR. Western blot was employed to examine protein expression. Cell proliferation was measured using CCK-8. Transwell assay was adopted to analyze cell migration and invasion. The relationship between genes was explored through bioinformatics analysis, dual-luciferase reporter gene assay and spearman correlation coefficient. We found that circGMPS was elevated in GC exosomes, tissues and cells. Poor prognosis of GC patients was related to high circGMPS expression. Both exosome co-culture with cells and insertion of circGMPS clearly promoted cell progression. Mechanically, circGMPS sponged miR-144-3p to regulate PUM1. Inhibition of PUM1 or miR-144-3p overexpression inhibited the malignant GC cell progression. Our data confirmed that exosome-derived circGMPS boosted malignant progression by miR-144-3p/PUM1 axis in GC cells, providing strong evidences for circGMPS as a clinical biomarker of GC treatment.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10616-023-00597-9.

NORAD-Regulated Signaling Pathways in Breast Cancer Progression

Long non-coding RNA activated by DNA damage (NORAD) has recently been associated with pathologic mechanisms underlying cancer progression. Due to NORAD's extended range of interacting partners, there has been contradictory data on its oncogenic or tumor suppressor roles in BC. This review will summarize the function of NORAD in different BC subtypes and how NORAD impacts crucial signaling pathways in this pathology. Through the preferential binding to pumilio (PUM) proteins PUM1 and PUM2, NORAD has been shown to be involved in the control of cell cycle, angiogenesis, mitosis, DNA replication and transcription and protein translation. More recently, NORAD has been associated with PUM-independent roles, accomplished by interacting with other ncRNAs, mRNAs and proteins. The intricate network of NORAD-mediated signaling pathways may provide insights into the potential design of novel unexplored strategies to overcome chemotherapy resistance in BC treatment.

[Research Progress in the Role of Liquid-Liquid Phase Separation in Human Cancer]

Liquid-liquid phase separation (LLPS) is a reversible process, during which biological macromolecules, including proteins and nucleic acids, condense into liquid membraneless organelles under the influence of weak multivalent interactions. Currently, fluorescence recovery after photobleaching is the primary method used to detect the phase separation of biological macromolecules. Recent studies have revealed the link between abnormal LLPS and the pathogenesis and development of various human cancers. Through phase separation or abnormal phase separation, tumor-related biological macromolecules, such as mRNA, long noncoding RNAs (lncRNAs), and tumor-related proteins, can affect transcriptional translation and DNA damage repair, regulate the autophagy and ferroptosis functions of cells, and thus regulate the development of various tumors. In this review, we summarized the latest research findings on the mechanism of LLPS in the pathogenesis and progression of tumors and elaborated on the promotion or inhibition of autophagy, tumor immunity, DNA damage repair, and cell ferroptosis after abnormal phase separation of biomolecules, including mRNA, lncRNA, and proteins, which subsequently affects the pathogenesis and progression of tumors. According to published findings, many biological macromolecules can regulate transcriptional translation, expression, post-transcriptional modification, cell signal transduction, and other biological processes through phase separation. Therefore, further expansion of the research field of phase separation and in-depth investigation of its molecular mechanisms and regulatory processes hold extensive research potential.

Diagnostic implications of lncRNA NORAD in breast cancer

This study aimed to assess the expression levels of non-coding RNA activated by DNA damage (NORAD) in the cells, tissues, and serum of breast cancer (BRCA) patients and benign breast nodules and investigate its association with clinicopathological characteristics and prognosis in BRCA. NORAD was analyzed using TCGA-BRCA, GSE77308, Cellminer, and Sangerbox databases, revealing its significance in BRCA prognosis, immune microenvironment, and cell function. Serum samples from 38 BRCA patients, 80 patients with benign breast nodules (50 fibroadenoma and 30 breast adenosis cases), and 42 healthy individuals were collected from Zhejiang Xiaoshan Hospital. NORAD expression was quantified using quantitative reverse transcription PCR (RT-qPCR). Differential NORAD expression between benign and malignant breast nodules and its relationship to clinicopathological characteristics were assessed. NORAD demonstrated elevated expression in BRCA patient serum compared to healthy individuals and those with benign breast nodules (P < 0.05). Moreover, its expression correlated with TNM-stage, lymph node metastasis, and luminal classification. These findings highlight the elevated NORAD expression in BRCA patient serum and its correlation with clinicopathological characteristics, providing insights into its potential as a diagnostic biomarker or therapeutic target.

The expression of lncRNAs CASC2, NEAT1, LINC00299 in breast cancer tissues and their relationship with the XBP1 splicing rate in Iranian patients during 2014-2019: A cross-sectional study

Background and Aims

Breast cancer is a leading cause of incidence and mortality in women globally. Identifying new molecular markers can aid in cancer diagnosis, targeted therapy, and treatment monitoring. This study aimed to measure the expression of the X-box binding protein 1 (XBP1) gene, an index of the unfolded protein response (UPR), and long noncoding RNAs (lncRNAs), including Nuclear Enriched Abundant Transcript 1 (NEAT1), Cancer Susceptibility Candidate 2 (CASC2), and Long Intergenic Nonprotein Coding RNA 299 (LINC00299), as possible regulators of the UPR pathway.

Methods

Total RNA was extracted from 40 samples of breast tumor tissues and their respective controls. The expression level of lncRNAs CASC2, NEAT1, and LINC00299 was quantified using reverse transcription-polymerase chain reaction (RT-PCR). The ratio of the spliced form of XBP1 to its unspliced form (XBP1u) was determined by PCR and electrophoresis.

Results

The results showed a 2.8-fold increase in the ratio of XBP1s/u in breast cancer tissues compared to adjacent nonmalignant samples (p < 0.05). Additionally, the level of lncRNAs NEAT1, CASC2, and LINC00299 in breast tumor tissues increased significantly by twofold, 1.5-fold, and 2.3-fold, respectively, compared to adjacent nonmalignant samples (p < 0.05).

Conclusions

Based on the association between the expression of lncRNAs CASC2, LINC00299, and NEAT1 and the XBP1s/u ratio, these lncRNAs could be potential regulators of the UPR pathway. Also, CASC2 and NEAT1 genes could be suggested as suitable biomarkers to distinguish cancerous tissue from noncancerous breast tissue due to their significant increase in expression in cancerous samples compared to adjacent noncancerous.

m6A Modification Mediates Exosomal LINC00657 to Trigger Breast Cancer Progression Via Inducing Macrophage M2 Polarization

BACKGROUND

Exosome-mediated transfer of long noncoding RNAs (lncRNAs) is critical for the cell-cell crosstalk in the tumor microenvironment. Nevertheless, the role of breast cancer (BC) cell-derived exosomal lncRNA in macrophage polarization during the development of BC remains unclear.

METHODS

The key lncRNAs carried by BC cell-derived exosomes were identified by RNA-seq. CCK-8, flow cytometry, and transwell assay were conducted to analyze the role of LINC00657 in BC cells. In addition, immunofluorescence, qRT-PCR, western blot, and MeRIP-PCR were used to evaluate the function and underlying mechanism of exosomal LINC00657 in macrophage polarization.

RESULTS

LINC00657 was distinctly upregulated in BC-derived exosomes and it was associated with increased m6A methylation modification levels. In addition, the depletion of LINC00657 significantly diminished the proliferative activity, migration and invasion potential of BC cells, and it also accelerated cell apoptosis. Exosomal LINC00657 from MDA-MB-231 cells could facilitate macrophage M2 activation, thus stimulating BC development in turn. Furthermore, LINC00657 activated the TGF-β signaling pathway by sequestering miR-92b-3p in macrophages.

CONCLUSION

Exosomal LINC00657 secreted by BC cells could induce macrophage M2 activation, and these macrophages preferentially contributed to the malignant phenotype of BC cells. These results improve our understanding of BC and suggest a new therapeutic strategy for patients with BC.

Hsa-miR-323a-3p functions as a tumor suppressor and targets STAT3 in neuroblastoma cells

Background

Studies conducted in the last decades have revealed a role for the non-coding microRNAs (miRNAs) in cancer development and progression. Several miRNAs within the chromosome region 14q32, a region commonly deleted in cancers, are associated with poor clinical outcome in the childhood cancer neuroblastoma. We have previously identified miR-323a-3p from this region to be downregulated in chemotherapy treated neuroblastoma cells compared to pre-treatment cells from the same patients. Furthermore, in neuroblastoma tumors, this miRNA is downregulated in advanced stage 4 disease compared to stage 1-2. In this study, we attempt to delineate the unknown functional roles of miR-323a-3p in neuroblastoma.

Methods

Synthetic miRNA mimics were used to overexpress miR-323a-3p in neuroblastoma cell lines. To investigate the functional roles of miR-323a-3p, cell viability assay, flow cytometry, reverse transcription-quantitative polymerase chain reaction, luciferase reporter assay and western blot were conducted on the neuroblastoma cell lines Kelly, SH-SY5Y and SK-N-BE(2)-C.

Results

Ectopic expression of miR-323a-3p resulted in marked reduction of cell viability in Kelly, SH-SY5Y and SK-N-BE(2)-C by causing G1-cell cycle arrest in Kelly and SH-SY5Y and apoptosis in all the cell lines tested. Furthermore, mRNA and protein levels of signal transducer and activator of transcription 3 (STAT3) were reduced upon miR-323a-3p overexpression. A direct binding of the miR-323a-3p to the 3'UTR of STAT3 was experimentally validated by luciferase reporter assay, where miR-323a-3p reduced luminescent signal from full length STAT3 3'UTR luciferase reporter, but not from a reporter with mutation in the predicted seed sequence.

Conclusions

miR-323a-3p inhibits growth of neuroblastoma cell lines through G1-cell cycle arrest and apoptosis, and the well-known oncogene STAT3 is a direct target of this miRNA.

The Potential of NORAD-PUMILIO-RALGAPB Regulatory Axis as a Biomarker in Breast Cancer

Introduction: Long non-coding RNAs (LncRNA) represent a heterogeneous family of RNAs that have emerged as regulators of various biological processes through their association with proteins in ribonucleoproteins complexes. The dynamic of these interactions can affect cell metabolism, including cancer development. Annually, breast cancer causes thousands of deaths worldwide, and searching for new biomarkers is pivotal for better diagnosis and treatment. Methods: Based on in silico prediction analysis, we focus on LncRNAs that have binding sites for PUMILIO, an RBP family involved in post-transcriptional regulation and associated with cancer progression. We compared the expression levels of these LncRNAs in breast cancer and non-tumor samples from the TCGA database. We analyzed the impact of overall and disease-free survival associated with the expression of the LncRNAs and co-expressed genes and targets of PUMILIO proteins. Results: Our results found NORAD as the most relevant LncRNA with a PUMILIO binding site in breast cancer, differently expressed between Luminal A and Basal subtypes. Additionally, NORAD was co-expressed in a Basal-like subtype (0.55) with the RALGAPB gene, a target gene of PUMILIO related to chromosome stability during cell division. Conclusion: These data suggest that this molecular axis may provide insights for developing novel therapeutic strategies for breast cancer.

Modulation and function of Pumilio proteins in cancer

Post-transcriptional regulation is involved in tumorigenesis, and in this control, RNA-binding proteins are the main protagonists. Pumilio proteins are highly conserved RNA-binding proteins that regulate many aspects of RNA processing. The dysregulation of Pumilio expression is associated with different types of cancer. This review summarizes the roles of Pumilio 1 and Pumilio 2 in cancer and discusses the factors that account for their distinct biological functions. Pumilio levels seem to be related to tumor progression and poor prognoses in some kinds of tumors, such as lung, pancreatic, prostate, and cervical cancers. Pumilio 1 is associated with cancer proliferation, migration, and invasion, and so is Pumilio 2, although there are contradictory reports regarding the latter. Furthermore, the circular RNA, circPUM1, has been described as a miRNAs sponge, regulating miRNA involved in the cell cycle. The expression and function of Pumilio proteins depend on the fine adjustment of a set of modulators, including miRNAs, lncRNAs, and circRNAs; this demonstrates that Pumilio plays an important role in tumorigenesis through a variety of regulatory axes.

Discovering Common miRNA Signatures Underlying Female-Specific Cancers via a Machine Learning Approach Driven by the Cancer Hallmark ERBB

Big data processing, using omics data integration and machine learning (ML) methods, drive efforts to discover diagnostic and prognostic biomarkers for clinical decision making. Previously, we used the TCGA database for gene expression profiling of breast, ovary, and endometrial cancers, and identified a top-scoring network centered on the ERBB2 gene, which plays a crucial role in carcinogenesis in the three estrogen-dependent tumors. Here, we focused on microRNA expression signature similarity, asking whether they could target the ERBB family. We applied an ML approach on integrated TCGA miRNA profiling of breast, endometrium, and ovarian cancer to identify common miRNA signatures differentiating tumor and normal conditions. Using the ML-based algorithm and the miRTarBase database, we found 205 features and 158 miRNAs targeting ERBB isoforms, respectively. By merging the results of both databases and ranking each feature according to the weighted Support Vector Machine model, we prioritized 42 features, with accuracy (0.98), AUC (0.93–95% CI 0.917–0.94), sensitivity (0.85), and specificity (0.99), indicating their diagnostic capability to discriminate between the two conditions. In vitro validations by qRT-PCR experiments, using model and parental cell lines for each tumor type showed that five miRNAs (hsa-mir-323a-3p, hsa-mir-323b-3p, hsa-mir-331-3p, hsa-mir-381-3p, and hsa-mir-1301-3p) had expressed trend concordance between breast, ovarian, and endometrium cancer cell lines compared with normal lines, confirming our in silico predictions. This shows that an integrated computational approach combined with biological knowledge, could identify expression signatures as potential diagnostic biomarkers common to multiple tumors.

MiR-323a regulates ErbB3/EGFR and blocks gefitinib resistance acquisition in colorectal cancer

The rapid onset of resistance to epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) limits its clinical utility in colorectal cancer (CRC) patients, and pan-erb-b2 receptor tyrosine kinase (ErbB) treatment strategy may be the alternative solution. The aim of this study was to develop a possible microRNA multi-ErbB treatment strategy to overcome EGFR-TKI resistance. We detect the receptor tyrosine kinase activity in gefitinib-resistant colorectal cancer cells, ErbB3/EGFR is significantly activated and provides a potential multi-ErbB treatment target. MiR-323a-3p, a tumor suppressor, could target both ErbB3 and EGFR directly. Apoptosis is the miR-323a-3p inducing main biological process by functional enrichment analysis, and The EGFR and ErbB signaling are the miR-323a-3p inducing main pathway by KEGG analysis. MiR-323a-3p promotes CRC cells apoptosis by targeting ErbB3-phosphoinositide 3‐kinases (PI3K)/PKB protein kinase (Akt)/glycogen synthase kinase 3 beta (GSK3β)/EGFR-extracellular regulated MAP kinase (Erk1/2) signaling directly. And miR-323a-3p, as a multi-ErbBs inhibitor, increase gefitinib sensitivity of the primary cell culture from combination miR-323a-3p and gefitinib treated subcutaneous tumors. MiR-323a-3p reverses ErbB3/EGFR signaling activation in gefitinib-resistant CRC cell lines and blocks acquired gefitinib resistance.

Suppression of lncRNA NORAD may affect cell migration and apoptosis in gastric cancer cells

BACKGROUND

Gastric cancer (GC) is a major malignancy that threatens people's lives worldwide. Long noncoding RNA (lncRNA) non-coding RNA activated by DNA damage (NORAD) is known to be a potential oncogene in many cancers and may promote cell migration and metastasis, and decrease apoptosis rate.

MATERIAL AND METHODS

NORAD expression was measured in 70 pairs of GC tissues and their adjacent normal tissues (ANTs) by quantitative real-time polymerase chain reaction. Si-NORAD gene knockdown study and cellular assays were conducted to assess the correlation between NORAD expression and cell viability, apoptosis, migration, and metastasis.

RESULTS

NORAD was significantly overexpressed in GC tissues compared to ANTs (P value < 0.0001). The receiver operating characteristic curve indicated the AUC of 0.721 with the sensitivity and specificity of 78.57 and 61.43, respectively (P value < 0.0001). NORAD downregulation leads to decreased cell viability (P value < 0.001) and migration (P value < 0.01), increased apoptosis rate (P value < 0.0001), and increased protein level for PTEN, E-cadherin, and Bax, but decreased protein level for Bcl-2.

CONCLUSION

Generally, NORAD may serve as a potential diagnostic biomarker in GC.

Identification of serum exosomal miR-98-5p, miR-183-5p, miR-323-3p and miR-19b-3p as potential biomarkers for glioblastoma patients and investigation of their mechanisms

BACKGROUND

Exosomal miRNAs have attracted increasing interest as potential biomarkers and treatment targets for cancers, however, glioblastoma (GBM)-related exosomal miRNAs remain rarely reported. The study aimed to screen crucial serum exosomal miRNAs in GBM patients and explored their possible mechanisms.

METHODS

Serum exosomal miRNA profile datasets of GBM patients and normal controls were downloaded from the Gene Expression Omnibus database (GSE112462 and GSE122488). The differentially expressed miRNAs (DEMs) were identified using the limma method. Their diagnostic values were assessed by receiver operating characteristic (ROC) curve analysis. The target genes of DEMs were predicted by the miRwalk 2.0 database. Function enrichment analysis was performed using the DAVID database. The expression and prognosis of target genes were validated using TCGA sequencing data and immunohistochemistry.

RESULTS

Seven DEMs were shared in two datasets, among which hsa-miR-183-5p and hsa-miR-98-5p as well as has-miR-323-3p or has-miR-19b-3p constituted a diagnostic signature to distinguish GBM from controls, with the area under the ROC curve nearly approximate to 1. MAPK8IP1/FAM175B, OSMR/CASP3, PTPN2 and FBXO32 may be underlying targets for hsa-miR-183-5p, hsa-miR-98-5p, has-miR-323-3p and has-miR-19b-3p, respectively. Function analysis showed all of these target genes were involved in cell proliferation and related signaling pathways [positive regulation of cell proliferation (OSMR), negative regulation of transcription from RNA polymerase II promoter (PTPN2), cell division (FAM175B), regulation of transcription, DNA-templated (MAPK8IP1), hsa05200:Pathways in cancer (CASP3) and hsa04068:FoxO signaling pathway (FBXO32)]. The protein and (or mRNA) expression levels of OSMR, CASP3, PTPN2 and FBXO32 were validated to be upregulated, while MAPK8IP1 and FAM175B were downregulated in GBM tissues. Also, OSMR, CASP3, PTPN2 and FBXO32 were associated with patients' prognosis.

CONCLUSION

These findings suggest these four exosomal miRNAs may represent potential diagnostic biomarkers and therapeutic targets for GBM.

Non-coding RNA Activated by DNA Damage: Review of Its Roles in the Carcinogenesis

Long intergenic non-coding RNA 00657 (LINC00657) or "non-coding RNA activated by DNA damage" (NORAD) is an extremely conserved and copious long non-coding RNA (lncRNA). This transcript has pivotal role in the preservation of genome integrity. Several researches have appraised the role of NORAD in the evolution of human cancers with most of them indicating an oncogenic role for this lncRNA. Several miRNAs such as miR-199a-3p, miR-608, miR-155-5p, miR-590-3p, miR-495-3p, miR-608, miR-202-5p, miR-125a-3p, miR-144-3p, miR-202-5p, and miR-30a-5p have been recognized as targets of NORAD in different cancer cell lines. In addition, NORAD has interactions with cancer-related pathways, particularly STAT, TGF-β, Akt/mTOR, and PI3K/AKT pathway. Over-expression of NORAD has been related with poor clinical outcome of patients with diverse types of neoplasms. Collectively, NORAD is a prospective marker and target for combating cancer.