MiR-205-5p-Mediated MAGI1 Inhibition Attenuates the Injury Induced by Diabetic Nephropathy.

INTRODUCTION: Membrane-associated guanylate kinase with an inverted domain structure-1 (MAGI1) is dysregulated in diabetes; however, its role in diabetic nephropathy (DN) remains unclear. In this study, we determined the function and associated mechanisms of MAGI1 in DN. METHODS: Serum samples from 28 patients with DN and 28 normal volunteers were collected. High-glucose (HG)-treated human renal mesangial cells (HRMCs) and streptozotocin-treated rats were used as cell and animal models of DN, respectively. MAGI1 mRNA expression was measured by quantitative reverse transcription polymerase chain reaction. An 5-Ethynyl-2'-deoxyuridine assay was used to assess cell proliferation, whereas Western blot analysis was performed to quantitate the levels of markers associated with proliferation, the extracellular matrix (ECM), and inflammation. These included collagens I, collagen IV, cyclin D1, AKT, phosphorylated-AKT (p-AKT), PI3K, and phosphorylated-PI3K (p-PI3K). The predicted binding of miR-205-5p with the MAGI1 3'UTR was verified using a luciferase assay. RESULTS: MAGI1 expression was increased in serum samples from DN patients and in HRMCs treated with HG. MAGI1 knockdown attenuated excessive proliferation, ECM accumulation, and inflammation in HG-induced HRMCs as well as injury to DN rats. MiR-205-5p potentially interacted with the 3'UTR of MAGI1 and binding was verified using a dual-luciferase reporter assay. Moreover, miR-205-5p repression offset the inhibitory influence of MAGI1 knockdown on proliferation, collagen deposition, and inflammation in HG-treated HRMCs. CONCLUSION: MAGI1 contributes to injury caused by DN. Furthermore, miR-205-5p binds to MAGI1 and suppresses MAGI1 function. These findings suggest that miR-205-5p-mediates MAGI1 inhibition, which represents a potential treatment for DN.

Glioma stem cell-derived exosomes induce the transformation of astrocytes via the miR-3065-5p/DLG2 signaling axis.

Tumor-associated astrocytes (TAAs) in the glioblastoma microenvironment play an important role in tumor development and malignant progression initiated by glioma stem cells (GSCs). In the current study, normal human astrocytes (NHAs) were cultured and continuously treated with GSC-derived exosomes (GSC-EXOs) induction to explore the mechanism by which GSCs affect astrocyte remodeling. This study revealed that GSC-EXOs can induce the transformation of NHAs into TAAs, with relatively swollen cell bodies and multiple extended processes. In addition, high proliferation, elevated resistance to temozolomide (TMZ), and increased expression of TAA-related markers (TGF-ß, CD44, and tenascin-C) were observed in the TAAs. Furthermore, GSC-derived exosomal miR-3065-5p could be delivered to NHAs, and miR-3065-5p levels increased significantly in TAAs, as verified by miRNA expression profile sequencing and Reverse transcription polymerase chain reaction. Overexpression of miR-3065-5p also enhanced NHA proliferation, elevated resistance to TMZ, and increased the expression levels of TAA-related markers. In addition, both GSC-EXO-induced and miR-3065-5p-overexpressing NHAs promoted tumorigenesis of GSCs in vivo. Discs Large Homolog 2 (DLG2, downregulated in glioblastoma) is a direct downstream target of miR-3065-5p in TAAs, and DLG2 overexpression could partially reverse the transformation of NHAs into TAAs. Collectively, these data demonstrate that GSC-EXOs induce the transformation of NHAs into TAAs via the miR-3065-5p/DLG2 signaling axis and that TAAs can further promote the tumorigenesis of GSCs. Thus, precisely blocking the interactions between astrocytes and GSCs via exosomes may be a novel strategy to inhibit glioblastoma development, but more in-depth mechanistic studies are still needed.

Long non-coding RNAs PTENP1, GNG12-AS1, MAGI2-AS3 and MEG3 as tumor suppressors in breast cancer and their associations with clinicopathological parameters.

BACKGROUND: Breast cancer is the most commonly occurring cancer worldwide and is the main cause of death from cancer in women. Novel biomarkers are highly warranted for this disease. OBJECTIVE: Evaluation of novel long non-coding RNAs biomarkers for breast cancer. METHODS: The study comprised the analysis of the expression of 71 candidate lncRNAs via screening, six of which (four underexpressed, two overexpressed) were validated and analyzed by qPCR in tumor tissues associated with NST breast carcinomas, compared with the benign samples and with respect to their clinicopathological characteristics. RESULTS: The results indicated the tumor suppressor roles of PTENP1, GNG12-AS1, MEG3 and MAGI2-AS3. Low levels of both PTENP1 and GNG12-AS1 were associated with worsened progression-free and overall survival rates. The reduced expression of GNG12-AS1 was linked to the advanced stage. A higher grade was associated with the lower expression of PTENP1, GNG12-AS1 and MAGI2-AS3. Reduced levels of both MEG3 and PTENP1 were linked to Ki-67 positivity. The NRSN2-AS1 and UCA1 lncRNAs were overexpressed; higher levels of UCA1 were associated with multifocality. CONCLUSIONS: The results suggest that the investigated lncRNAs may play important roles in breast cancer and comprise a potential factor that should be further evaluated in clinical studies.

G protein-coupled estrogen receptor (GPER)/GPR30 forms a complex with the ß1-adrenergic receptor, a membrane-associated guanylate kinase (MAGUK) scaffold protein, and protein kinase A anchoring protein (AKAP) 5 in MCF7 breast cancer cells.

G protein-coupled receptor 30 (GPR30), also named G protein-coupled estrogen receptor (GPER), and the ß1-adrenergic receptor (ß1AR) are G protein-coupled receptors (GPCR) that are implicated in breast cancer progression. Both receptors contain PSD-95/Discs-large/ZO-1 homology (PDZ) motifs in their C-terminal tails through which they interact in the plasma membrane with membrane-associated guanylate kinase (MAGUK) scaffold proteins, and in turn protein kinase A anchoring protein (AKAP) 5. GPR30 constitutively and PDZ-dependently inhibits ß1AR-mediated cAMP production. We hypothesized that this inhibition is a consequence of a plasma membrane complex of these receptors. Using co-immunoprecipitation, confocal immunofluorescence microscopy, and bioluminescence resonance energy transfer (BRET), we show that GPR30 and ß1AR reside in close proximity in a plasma membrane complex when transiently expressed in HEK293. Deleting the GPR30 C-terminal PDZ motif (-SSAV) does not interfere with the receptor complex, indicating that the complex is not PDZ-dependent. MCF7 breast cancer cells express GPR30, ß1AR, MAGUKs, and AKAP5 in the plasma membrane, and co-immunoprecipitation revealed that these proteins exist in close proximity also under native conditions. Furthermore, expression of GPR30 in MCF7 cells constitutively and PDZ-dependently inhibits ß1AR-mediated cAMP production. AKAP5 also inhibits ß1AR-mediated cAMP production, which is not additive with GPR30-promoted inhibition. These results argue that GPR30 and ß1AR form a PDZ-independent complex in MCF7 cells through which GPR30 constitutively and PDZ-dependently inhibits ß1AR signaling via receptor interaction with MAGUKs and AKAP5.

Lactate promoted cisplatin resistance in NSCLC by modulating the m6A modification-mediated FOXO3/MAGI1-IT1/miR-664b-3p/IL-6R axis.

BACKGROUND: Cisplatin resistance is one of the major obstacles in non-small cell lung cancer (NSCLC) treatment. Intriguingly, elevated lactate levels were observed in cisplatin-resistant cells, which spurred further investigation into their underlying biological mechanisms. METHODS: Lactate levels were measured by lactate detection kit. Cisplatin-resistance NSCLC cells were established using progressive concentration of cisplatin. Cell viability, proliferation, and apoptosis were detected by CCK-8, EdU, and flow cytometry, respectively. Cell proliferation in vivo was determined by immunohistochemistry of Ki67 and apoptotic cells were calculated by the TUNEL. MeRIP-PCR was used to measure FOXO3 m6A levels. The interactions of genes were analyzed via RIP, ChIP, Dual-luciferase reporter, and RNA pull-down, respectively. RESULTS: Elevated lactate levels were observed in both NSCLC patients and cisplatin-resistance cells. Lactate treatment increased cisplatin-resistance cell viability in vitro and promoted tumor growth in vivo. Mechanistically, lactate downregulated FOXO3 by YTHDF2-mediated m6A modification. FOXO3 transcriptionally reduced MAGI1-IT1 expression. FOXO3 overexpression inhibited the lactate-induced promotion of cisplatin resistance in NSCLC, which were reversed by MAGI1-IT1 overexpression. MAGI1-IT1 and IL6R competitively bound miR-664b-3p. FOXO3 overexpression or MAGI1-IT1 knockdown repressed lactate-mediated cisplatin resistance in vivo. CONCLUSION: Lactate promoted NSCLC cisplatin resistance through regulating FOXO3/MAGI1-IT1/miR-664b-3p/IL6R axis in YTHDF2-mediated m6A modification.

DLG2 intragenic exonic deletions reinforce the link to neurodevelopmental disorders and suggest a potential association with congenital anomalies and dysmorphism.

PURPOSE: Multiple studies suggest an association between DLG2 and neurodevelopmental disorders and indicate the haploinsufficiency of this gene; however, few cases have been thoroughly described. We performed additional studies to confirm this clinical association and DLG2 haploinsufficiency. METHODS: Chromosomal microarray analysis was performed on 11,107 patients at the Cytogenetics Laboratory at the University of Alabama at Birmingham. The Database of Genomic Variants-Gold Standard Variants and the Genome Aggregation Database were selected for the association analysis. Fifty-nine patients from the literature and DECIPHER, all having DLG2 intragenic deletions, were included for comprehensive analysis of the distribution of these deletions. RESULTS: A total of 13 patients with DLG2 intragenic deletions, from 10 families in our cohort, were identified. Nine of 10 probands presented with clinical features of neurodevelopmental disorders. Congenital anomalies and dysmorphism were common in our cohort of patients. Association analysis showed that the frequency of DLG2 deletions in our cohort is significantly higher than those in the Database of Genomic Variants-Gold Standard Variants and the Genome Aggregation Database. Most of DLG2 intragenic deletions identified in 69 unrelated patients from our cohort, the literature, and DECIPHER map to the 5' region of the gene, with a hotspot centered around HPin7, exon 8, and HPin8. CONCLUSION: Our findings reinforce the link between DLG2 intragenic deletions and neurodevelopmental disorders, strongly support the haploinsufficiency of this gene, and indicate that these deletions might also have an association with congenital anomalies and dysmorphism.

LncRNA MAGI2-AS3 inhibites tumor progression by up-regulating STAM via interacting with miR-142-3p in clear cell renal cell carcinoma.

Revealing the role of non-coding RNAs (ncRNAs) in inducing dysregulated pathological responses to external signals may identify therapeutic targets for inhibiting the progression of clear cell renal cell carcinoma (ccRCC). Non-coding RNAs belong to a class of RNA molecules that do not encode proteins but possess diverse biological functions, playing essential roles in the occurrence and development of metastatic and proliferative tumors. To investigate the impact of the upstream interaction between miR-142-3p and lncRNA MAGI2-AS3 on the tumor-suppressive activity of the STAM gene, we firstly conducted bioinformatics analysis to predict the upstream miRNAs of STAM and the upstream lncRNAs of the miRNAs through online databases (miRanda, miRDB, TargetScan, LncBase v2), which were further validated by the starBasev2.0 database. Subsequently, multiple experimental techniques were employed to validate these findings, including RT-qPCR, Western blotting, measurement of cellular functional activity, and luciferase reporter assays. Through these experimental methods, we provided compelling evidence regarding the role of miR-142-3p and MAGI2-AS3 in regulating STAM gene expression and functionality, revealing their potential significance in tumor suppression. Our research demonstrates the importance of the MAGI2-AS3/miR-142-3p/STAM signaling pathway axis in ccRCC. MAGI2-AS3 competes for binding with miR-142-3p, resulting in upregulated STAM gene expression. This upregulation inhibits tumor proliferation and metastasis in ccRCC cells. Conversely, overexpression of miR-142-3p or silencing of MAGI2-AS3 promotes tumor behavior, while downregulation of miR-142-3p inhibits the development of ccRCC. Targeting the MAGI2-AS3/miR-142-3p/STAM axis holds promise as a therapeutic strategy for ccRCC treatment.

Screening of m6A gene-related lncRNAs in colon adenocarcinoma and construction of a prognostic prediction model.

OBJECTIVE: We aimed to screen the long non-coding RNAs (lncRNAs) related to N6-methyladenosine (m6A) gene and build the prognostic prediction model of colon adenocarcinoma (COAD). MATERIALS AND METHODS: The RNA sequencing data of 435 COAD cases with clinical survival and prognosis information and the GSE39582 dataset were obtained from TCGA and GEO, respectively. The lncRNAs related to the m6A gene with significant independent prognosis were identified. We used Cox regression analyses to acquire the lncRNAs associated with prognosis. Moreover, we built a prognostic prediction model of COAD. The Cox regression analyses were applied to obtain the independent prognostic clinical factors. Furthermore, we built the ceRNA regulation network of COAD, and the gene ontology (GO) and Kyoto Encyclopedia of Genes (KEGG) enrichment analysis for the lncRNAs was applied. RESULTS: Overall, 5 lncRNAs (MAGI1-IT1, CSNK1G2-AS1, ALMS1-IT1, LINC01341, LOXL1-AS1) related to m6A gene with significant independent prognosis were acquired. A prognostic prediction model of COAD was built, and 4 correlation-independent prognostic factors were found. In addition, the ceRNA regulation network of COAD was built, and mRNAs were significantly enriched in the 15 GO biological processes (such as regulation of transcription) and in 14 KEGG pathways (such as taurine). CONCLUSIONS: We identified 5 lncRNAs related to the m6A gene with significant independent prognosis. The ceRNA regulation network of COAD was built, which has great significance for identifying the biomarkers associated with m6A in COAD.

Long Noncoding RNA MAGI2-AS3 Represses Cell Progression in Clear Cell Renal Cell Carcinoma by Modulating the miR-629-5p/PRDM16 Axis.

The objective of this study was to determine the regulatory mechanism of MAGI2-AS3 in clear cell renal cell carcinoma (ccRCC), thereby supplying a new insight for ccRCC treatment. Expression data in TCGA-KIRC were obtained. Target gene lncRNA for research was determined using expression analysis and clinical analysis. lncRNA's downstream regulatory miRNA and mRNA were predicted by bioinformatics databases. ccRCC cell malignant phenotypes were detected via CCK-8, colony formation, Transwell migration, and invasion assays. The targeting relationship between genes was assessed through dual-luciferase reporter gene analysis. Kaplan-Meier (K-M) analysis was carried out to verify the effect of MAGI2-AS3, miR-629-5p, and PRDM16 on the survival rate of ccRCC patients. MAGI2-AS3 expression in ccRCC tissue and cells was shown to be markedly decreased and its expression to continuously decline with tumor progression. MAGI2-AS3 suppresses ccRCC proliferation and migration. Dual-luciferase assay showed that MAGI2-AS3 binds miR-629-5p and that miR-629-5p binds PRDM16. In addition, functional experiments showed that MAGI2-AS3 facilitates PRDM16 expression by repressing miR-629-5p expression, thereby suppressing ccRCC cell aggression. K-M analysis showed that upregulation of either MAGI2-AS3 or PRDM16 significantly improves ccRCC patient survival, while upregulation of miR-629-5p has no significant impact. MAGI2-AS3 sponges miR-629-5p to modulate PRDM16 to mediate ccRCC development. Meanwhile, the MAGI2-AS3/miR-629-5p/PRDM16 axis, as a regulatory pathway of ccRCC progression, may be a possible therapeutic target and prognostic indicator of ccRCC.

Targeting MAGI2-AS3-modulated Akt-dependent ATP-binding cassette transporters as a possible strategy to reverse temozolomide resistance in temozolomide-resistant glioblastoma cells.

Drug resistance is a major impediment to the successful treatment of glioma. This study aimed to elucidate the effects and mechanisms of the long noncoding RNA membrane-associated guanylate kinase inverted-2 antisense RNA 3 (MAGI2-AS3) on temozolomide (TMZ) resistance in glioma cells. MAGI2-AS3 expression in TMZ-resistant glioblastoma (GBM) cells was analyzed using the Gene Expression Omnibus data set GSE113510 and quantitative real-time PCR (qRT-PCR). Cell viability and TMZ half-maximal inhibitory concentration values were determined using the MTT assay. Apoptosis and cell cycle distribution were evaluated using flow cytometry. The expression of multidrug resistance 1 (MDR1), ATP-binding cassette superfamily G member 2 (ABCG2), protein kinase B (Akt), and phosphorylated Akt was detected using qRT-PCR and/or western blot analysis. MAGI2-AS3 was expressed at low levels in TMZ-resistant GBM cells relative to that in their parental cells. MAGI2-AS3 re-expression alleviated TMZ resistance in TMZ-resistant GBM cells. MAGI2-AS3 overexpression also accelerated TMZ-induced apoptosis and G2/M phase arrest. Mechanistically, MAGI2-AS3 overexpression reduced MDR1 and ABCG2 expression and inhibited the Akt pathway, whereas Akt overexpression abrogated the reduction in MDR1 and ABCG2 expression induced by MAGI2-AS3. Moreover, activation of the Akt pathway inhibited the effects of MAGI2-AS3 on TMZ resistance. MAGI2-AS3 inhibited tumor growth and enhanced the suppressive effect of TMZ on glioma tumorigenesis in vivo. In conclusion, MAGI2-AS3 reverses TMZ resistance in glioma cells by inactivating the Akt pathway.

MAGI1 Prevents Senescence and Promotes the DNA Damage Response in ER+ Breast Cancer.

MAGI1 acts as a tumor suppressor in estrogen receptor-positive (ER+) breast cancer (BC), and its loss correlates with a more aggressive phenotype. To identify the pathways and events affected by MAGI1 loss, we deleted the MAGI1 gene in the ER+ MCF7 BC cell line and performed RNA sequencing and functional experiments in vitro. Transcriptome analyses revealed gene sets and biological processes related to estrogen signaling, the cell cycle, and DNA damage responses affected by MAGI1 loss. Upon exposure to TNF-α/IFN-γ, MCF7 MAGI1 KO cells entered a deeper level of quiescence/senescence compared with MCF7 control cells and activated the AKT and MAPK signaling pathways. MCF7 MAGI1 KO cells exposed to ionizing radiations or cisplatin had reduced expression of DNA repair proteins and showed increased sensitivity towards PARP1 inhibition using olaparib. Treatment with PI3K and AKT inhibitors (alpelisib and MK-2206) restored the expression of DNA repair proteins and sensitized cells to fulvestrant. An analysis of human BC patients' transcriptomic data revealed that patients with low MAGI1 levels had a higher tumor mutational burden and homologous recombination deficiency. Moreover, MAGI1 expression levels negatively correlated with PI3K/AKT and MAPK signaling, which confirmed our in vitro observations. Pharmacological and genomic evidence indicate HDACs as regulators of MAGI1 expression. Our findings provide a new view on MAGI1 function in cancer and identify potential treatment options to improve the management of ER+ BC patients with low MAGI1 levels.

Extracellular vesicles carrying miR-6836 derived from resistant tumor cells transfer cisplatin resistance of epithelial ovarian cancer via DLG2-YAP1 signaling pathway.

Background: Chemotherapy resistance is a significant cause for poor prognosis of epithelial ovarian cancer (EOC). However, the molecular mechanism of chemo-resistance remains unclear, and developing available therapies and effective biomarkers for resistant EOC is in urgent demand. Stemness of cancer cells directly results in chemo-resistance. Exosomal miRNAs rebuild tumor microenvironment (TME) and act as widely used clinical liquid biopsy markers. Methods: In our study, high throughput screenings and comprehensive analysis were performed to screen for miRNAs, which were both up-regulated in resistant EOC tissues and related to stemness, and miR-6836 was identified accordingly. Results: Clinically, high miR-6836 expression was closely correlated with poor chemotherapy response and survival for EOC patients. Functionally, miR-6836 promoted EOC cell cisplatin resistance by increasing stemness and suppressing apoptosis. Mechanistically, miR-6836 directly targeted DLG2 to enhance Yap1 nuclear translocation, and was regulated by TEAD1 forming the positive feedback loop: miR-6836-DLG2-Yap1-TEAD1. Furthermore, miR-6836 could be packaged into secreted exosomes in cisplatin-resistant EOC cells and exosomal miR-6836 was able to be delivered into cisplatin-sensitive EOC cells and reverse their cisplatin response. Conclusion: Our study revealed the molecular mechanisms of chemotherapy resistance, and identified miR-6836 as the possible therapeutic target and effective biopsy marker for resistant EOC.

The human discs large protein 1 interacts with and maintains connexin 43 at the plasma membrane in keratinocytes.

Gap junction channels, composed of connexins, allow direct cell-to-cell communication. Connexin 43 (Cx43; also known as GJA1) is widely expressed in tissues, including the epidermis. In a previous study of human papillomavirus-positive cervical epithelial tumour cells, we identified Cx43 as a binding partner of the human homologue of Drosophila Discs large (Dlg1; also known as SAP97). Dlg1 is a member of the membrane associated-guanylate kinase (MAGUK) scaffolding protein family, which is known to control cell shape and polarity. Here, we show that Cx43 also interacts with Dlg1 in uninfected keratinocytes in vitro and in keratinocytes, dermal cells and adipocytes in normal human epidermis in vivo. Depletion of Dlg1 in keratinocytes did not alter Cx43 transcription but was associated with a reduction in Cx43 protein levels. Reduced Dlg1 levels in keratinocytes resulted in a reduction in Cx43 at the plasma membrane with a concomitant reduction in gap junctional intercellular communication and relocation of Cx43 to the Golgi compartment. Our data suggest a key role for Dlg1 in maintaining Cx43 at the plasma membrane in keratinocytes.

Role of MAGI2-AS3 in malignant and non-malignant disorders.

MAGI2 Antisense RNA 3 (MAGI2-AS3) is a long non-coding RNA (lncRNA) transcribed from a locus on 7q21.11. This lncRNA has been described to be abnormally expressed in a variety of malignancies in correlation with many clinical characteristics. Moreover, it might participate in the pathogenesis of congenital diaphragmatic hernia, Alzheimer's disease and intervertebral disc degeneration. Mechanistically, MAGI2-AS3 can serve as a molecular sponge for miR-142-3p, miR-424-5p, miR-15b, miR-233, miR-452-5p, miR-629-5p, miR-25, miR-155, miR-23a-3p, miR-519c-3p, miR-374b-5p, miR-374a, miR-31-5p, miR-3163, miR-525-5p, miR-15-5p, miR-374a-5p, miR-374b-5p, miR-218-5p, miR-141-3p and miR-200a-3p to regulate expression of their mRNA targets. The current review summarizes the role of MAGI2-AS3 in different disorders to highlight its importance in their pathophysiology.

Secretory MPP3 reinforce myeloid differentiation trajectory and amplify myeloid cell production.

Hematopoietic stem cells (HSC) and downstream lineage-biased multipotent progenitors (MPP) tailor blood production and control myelopoiesis on demand. Recent lineage tracing analyses revealed MPPs to be major functional contributors to steady-state hematopoiesis. However, we still lack a precise resolution of myeloid differentiation trajectories and cellular heterogeneity in the MPP compartment. Here, we found that myeloid-biased MPP3 are functionally and molecularly heterogeneous, with a distinct subset of myeloid-primed secretory cells with high endoplasmic reticulum (ER) volume and FcγR expression. We show that FcγR+/ERhigh MPP3 are a transitional population serving as a reservoir for rapid production of granulocyte/macrophage progenitors (GMP), which directly amplify myelopoiesis through inflammation-triggered secretion of cytokines in the local bone marrow (BM) microenvironment. Our results identify a novel regulatory function for a secretory MPP3 subset that controls myeloid differentiation through lineage-priming and cytokine production and acts as a self-reinforcing amplification compartment in inflammatory stress and disease conditions.

MAGI2-AS3 and miR-374b-5p as Putative Regulators of Multiple Sclerosis via Modulating the PTEN/AKT/IRF-3/IFN-ß Axis: New Clinical Insights.

Multiple sclerosis (MS) is a chronic disease and one of the leading causes of disability in young adults. The current study aims to investigate the pathogenesis of MS via studying the regulatory role of novel lncRNA MAGI2-AS3 in miR-374b-5p and their downstream targets PTEN/AKT/IRF-3/IFN-ß and the relationship of this pathway with disease severity. Moreover, it aims to assess the role of MAGI2-AS3/miR-374b-5p as diagnostic and/or prognostic biomarkers for MS. Overall, 150 contributors were recruited: 100 patients with MS and 50 healthy volunteers. Gene expression of MAGI2-AS3, miR-374b-5p, PTEN, AKT, and IRF-3 were assessed using RT-qPCR, and IFN-ß was measured by ELISA. Compared with the healthy control group, serum MAGI2-AS3 and PTEN were downregulated in MS patients, whereas miR-374b-5p, PI3K, AKT, IRF-3, and IFN-ß were upregulated in MS patients. Furthermore, MAGI2-AS3 was downregulated, while miR-374b-5p was upregulated in MS patients with an expanded disability status scale (EDSS) ≥3.5, compared to patients with an EDSS <3.5. Receiver-operating-characteristic curve analysis revealed that MAGI2-AS3 and miR-374b-5p can be used in the diagnosis of MS. Remarkably, multivariate logistic analysis revealed that MAGI2-AS3, miR-374b-5p, PTEN, and AKT act as independent variables in MS. Moreover, MAGI2-AS3 was directly correlated with PTEN and inversely correlated with miR-374b-5p, AKT, and EDSS. Regarding miR-374b-5p, it was positively correlated with AKT and EDSS. In conclusion, the study showed for the first time that the crosstalk between MAGI2-AS3 and miR-374b-5p could affect the AKT/IRF3/IFN-ß axis in MS. Interestingly, MAGI2-AS3 and miR-374b-5p could be genetic noninvasive biomarkers for MS.

lncRNA MAGI2-AS3 suppresses castration-resistant prostate cancer proliferation and migration via the miR-106a-5p/RAB31 axis.

Prostate cancer (PCa) is a common malignant cancer in elderly males in Western countries. Whole-genome sequencing confirmed that long non-coding RNAs (lncRNAs) are frequently altered in castration-resistant prostate cancer (CRPC) and promote drug resistance to cancer therapy. Therefore, elucidating the prospective role of lncRNAs in PCa oncogenesis and progression is of remarkable clinical significance. In this study, gene expression in prostate tissues was determined using RNA-sequencing datasets, and the gene diagnostic and prognostic values of CRPC were analyzed using bioinformatics. Further, the expression levels and clinical significance of MAGI2 Antisense RNA 3 (MAGI2-AS3) in PCa clinical specimens were evaluated. The tumor-suppressive activity of MAGI2-AS3 was functionally explored in PCa cell lines and animal xenograft models. MAGI2-AS3 was found to be aberrantly decreased in CRPC and was negatively correlated with Gleason score and lymph node status. Notably, low MAGI2-AS3 expression positively correlated with poorer survival in patients with PCa. The overexpression of MAGI2-AS3 significantly inhibited the proliferation and migration of PCa in vitro and in vivo. Mechanistically, MAGI2-AS3 could play a tumor suppressor function in CRPC through a novel miR-106a-5p/RAB31 regulatory network and could be a target for future cancer therapy.

Hypermethylation-Mediated lncRNA MAGI2-AS3 Downregulation Facilitates Malignant Progression of Laryngeal Squamous Cell Carcinoma via Interacting With SPT6.

Long noncoding RNAs (lncRNAs) have an effect on the occurrence and progression of a considerable number of diseases, especially cancer. Existing research has suggested that MAGI2 antisense RNA 3 (MAGI2-AS3) takes on a critical significance in the development of hepatocellular carcinoma and lung cancer. However, the functions of MAGI2-AS3 in laryngeal squamous cell carcinoma (LSCC) remain unclear. In this study, MAGI2-AS3 expression level in LSCC tissue and cell lines was detected, and the effect of MAGI2-AS3 overexpressed on LSCC phenotypes and the possible influence mechanisms were examined. MAGI2-AS3 was downregulated in the tissues of LSCC patients versus non-tumor tissues, and it was correlated with advanced TNM (tumor, node, metastasis) stage and lymph node metastases, as indicated by the results of this study. MAGI2-AS3 inhibited the proliferation, migration, and invasion of LSCC cells in vitro and in vivo. Furthermore, the hypermethylation level of the MAGI2-AS3 promoter region was indicated by bisulfite genomic sequencing and methylation-specific polymerase chain reaction, such that MAGI2-AS3 expression was downregulated. Besides, MAGI2-AS3 promoter hypermethylation was regulated by DNA methyltransferase 1 (DNMT1), and MAGI2-AS3 expression was reversed by 5-Aza-2'-deoxycytidine (5-Aza). Moreover, the result of the RNA pull-down experiment suggested that 38 proteins were enriched in the MAGI2-AS3 group versus the control group in TU177 cells. To be specific, SPT6 (ie, a conserved protein) was enriched by fold change >10. SPT6 knockdown reduced the antitumor effect of MAGI2-AS3 in TU177 and AMC-HN-8 cells. Meanwhile, SPT6 overexpression inhibited the proliferation, metastasis, and invasion of TU177 and AMC-HN-8 cells. As revealed by the above findings, DNMT1-regulated MAGI2-AS3 promoter hypermethylation led to downregulated MAGI2-AS3 expression, such that the presence and progression of LSCC were inhibited in an SPT6 binding-dependent manner.

Exosomal long noncoding RNAs MAGI2-AS3 and CCDC144NL-AS1 in oral squamous cell carcinoma development via the PI3K-AKT-mTOR signaling pathway.

BACKGROUND: Long noncoding RNAs (lncRNAs) are essential and critical components of signal and transduction, regulating the intracellular microenvironment. Serum exosomes (SEs) are involved in rearranging the intercellular functional lncRNAs, which may also play a role in oral squamous cell carcinoma (OSCC). The function of lncRNAs at the transcription level in SEs of patients with OSCC is partially understood. MATERIALS AND METHODS: The lncRNA expression profiles were examined derived from SEs from patients with OSCC with lymph node metastasis (OSCC-LNM), OSCC with no LNM (OSCC-NLNM), postoperative metastasis and recurrence OSCC (rOSCC) and healthy controls (HCs). Bioinformatics analysis was used to analyse differentially expressed lncRNAs (DE lncRNAs) and a total of 150 subjects were enrolled for RT-PCR verifications. The correlations of four lncRNAs and clinicopathologic factors, biochemical indexes were evaluated. MAGI2-AS3 and CCDC144NL-AS1 were overexpressed or silenced in oral cancer (OC) cells. The proliferation, invasion, and migration were evaluated to investigate the effect of MAGI2-AS3 and CCDC144NL-AS1 on the development of OSCC. The related proteins of PI3K-AKT-mTOR signal pathway were also detected. RESULTS: The expressions of the lncRNAs, namely MAGI2-AS3 and CCDC144NL-AS1, were significantly upregulated in rOSCC and OSCC-LNM. MAGI2-AS3 was overexpressed in cancer tissue compared to other control groups. AC109587.1 and AC010978.1 were significantly associated with the clinical stage, and CCDC144NL-AS1 was significantly associated with aging. MAGI2-AS3 and CCDC144NL-AS1 might promote cell proliferation, invasion, and migration in OSCC cells by regulating the PI3K-AKT-mTOR pathway. CONCLUSIONS: our results suggest that MAGI2-AS3 an d CCDC144NL-AS1 may have clinical applications in the treatment of OSCC.

Identification and Verification of a Novel MAGI2-AS3/miRNA-374-5p/FOXO1 Network Associated with HBV-Related HCC.

BACKGROUND: Hepatocellular carcinoma (HCC) is a very common neoplasm worldwide, and competitive endogenous RNA (ceRNA) plays an important role in the development of HCC. The purpose of this study is to investigate the molecular mechanisms of ceRNAs in HCC. METHODS: This study detects potential ceRNAs from HCC through whole genome analysis of lncRNA, miRNA and mRNA expression. We then performed high-throughput sequencing of tissues from five hepatitis B related HCC patients to screen ceRNAs and those screened ceRNAs expressions were verified on tissues from an independent group of six patients. Finally, the function of ceRNAs of interest was illustrated in vitro. RESULT: Functional and pathway analysis of The Cancer Genome Atlas revealed ceRNA networks. The high-throughput sequencing identified 985 upregulated and 1612 downregulated lncRNAs and 887 upregulated and 1116 downregulated mRNAs in HCC patients. Differentially expressed genes were parallel to cancer-associated processes, comprising 18 upregulated and 35 downregulated significantly enriched pathways including alcoholism and viral carcinogenesis. Among them, a potential ceRNA network was detected and verified in six HCC patients. CeRNAs of the lncRNA MAGI2-AS3/miR-374-5p/FOXO1 pathway were significantly dysregulated in HCC, and validation in vitro showed that FOXO1 is positively regulated by MAGI2-AS3 through the induction of miR-374a/b-5p in HCC cells. In addition, the overexpression of FOXO1 is associated with proliferation, migration, and invasion of HCC cells and increases apoptosis of HCC cells. MiR-374a/b-5p caused an opposite effect by directly suppressing FOXO1 in HCC cells. CONCLUSION: CeRNA networks were found in HCC and aberrantly expressed ceRNAs of lncRNA MAGI2-AS3/miR-374-5p/FOXO1 plays a crucial role in HCC, assisting in diagnosis and providing a method for treatment.