LncRNA MAGI2-AS3 inhibits tumor progression and angiogenesis by regulating ACY1 via interacting with transcription factor HEY1 in clear cell renal cell carcinoma

Genome-wide analysis of long noncoding RNAs as cis-acting regulators of transcription factor-encoding genes in IgA nephropathy

BACKGROUND

IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis in the world, but the disease pathogenesis noncoding is yet to be elucidated. Previous studies have revealed regulatory functions for long noncoding RNA (lncRNA) in various diseases; however, the roles of lncRNA in IgAN and regulation of transcription factors (TFs) have been scarcely investigated.

METHODS

Renal tissue samples (n = 5) from patients with IgAN and control samples (n = 4) were collected and RNA sequencing (RNA-seq) was performed. Four software programs were employed for lncRNA prediction. GO (Gene Ontology)/KEGG (Kyoto Encyclopedia of Genes and Genomes) were employed for analysis of the identified differentially expressed genes (DEGs). A regulatory network model of DE lncRNA-TF-DEG was developed, and the levels of expression of key lncRNAs, TFs, and corresponding target genes were assessed using qRT-PCR and immunofluorescence.

RESULTS

The current study identified 674 upregulated and 1,011 downregulated DE mRNAs and 260 upregulated and 232 downregulated DE lncRNAs in IgAN samples compared with control samples. The upregulated DE mRNAs showed enrichment in cell adhesion and collagen glial fiber organization pathways. The DE lncRNAs-DE mRNAs showing co-expression are associated with transmembrane transport. A novel regulatory network model of lncRNA-TF-DEG has been developed. This study identified seven TFs that are cis-regulated by 6 DE lncRNAs, and show co-expression with 132 DEGs (correlation coefficient ≥ 0.8, P ≤ 0.01), generating 158 pairs that showed co-expression. The lncRNAs NQO1-DT and RP5-1057120.6 were found to be highly expressed in IgAN samples. The TFs vitamin D Receptor (VDR) and NFAT5, along with their target genes were also aberrantly expressed.

CONCLUSION

Key lncRNAs and TFs centrally associated with IgAN have been identified in this study. A regulatory network model of lncRNA-TF-mRNA was constructed. Further studies on the genes identified herewith could provide insight into the pathogenesis of IgAN.

LINC00645 inhibits renal cell carcinoma progression by interacting with HNRNPA2B1 to regulate the ROCK1 mRNA stability

The lncRNA plays an important role in tumorigenesis and the progression of renal cell carcinoma (RCC). LINC00645 is one of the most different expressed lncRNA between RCC and normal renal tissue. However, the regulatory mechanism of LINC00645 in RCC remains unknown. Our results indicated that LINC00645 inhibited RCC proliferation, migration, and invasion. Mechanistically, HNRNPA2B1 directly bound to ROCK1 mRNA and strengthened its stability. LINC00645 competitively bound to the RRM1 domain, which is responsible for interacting with ROCK1 mRNA, reducing ROCK1 mRNA level by affecting posttranscriptional destabilization. The expression of LINC00645 was significantly reduced in RCC cells, significantly upregulating ROCK1 by abolishing the interaction with HNRNPA2B1, finally promoting RCC proliferation, migration, and invasion. Moreover, RCC cells with lower LINC00645 expression were more sensitive to the ROCK1 inhibitor Y-27632. Our study indicates that decreased expression of LINC00645 promotes the RCC progression via HNRNPA2B1/ROCK1 axis, providing a promising treatment strategy for RCC patients with decreased LINC00645 expression.

LOXL1-AS1 inhibits JAK2 ubiquitination and promotes cholangiocarcinoma progression through JAK2/STAT3 signaling

This study thoroughly investigated the role of the long non-coding RNA LOXL1-AS1 in the pathogenesis of cholangiocarcinoma (CCA). Through bioinformatics analysis and tissue samples validation, the study found that LOXL1-AS1 was significantly elevated in CCA, with its high expression closely tied to clinical pathological features and prognosis. In vitro and in vivo experiments revealed that LOXL1-AS1 was crucial in regulating CCA cell apoptosis, proliferation, migration, and invasion. Further investigations using FISH, subcellular localization experiments, RNA pull down, and RIP uncovered that LOXL1-AS1 primarily resided in the cytoplasm and influenced CCA progression by modulating the JAK2/STAT3 signaling pathway. Notably, LOXL1-AS1 might regulate the activity of JAK2 through modulating its ubiquitination and degradation. YY1 had also been found to act as an upstream transcription factor of LOXL1-AS1 to impact CCA cell malignancy. These findings shed light on the pivotal role of LOXL1-AS1 in CCA and offered potential directions for novel therapeutic strategies, providing a fresh perspective on tumor pathogenesis.

Regulation of Angiogenesis by Non-Coding RNAs in Cancer

Non-coding RNAs, including microRNAs, long non-coding RNAs, and circular RNAs, have been identified as crucial regulators of various biological processes through epigenetic regulation, transcriptional regulation, and post-transcriptional regulation. Growing evidence suggests that dysregulation and activation of non-coding RNAs are closely associated with tumor angiogenesis, a process essential for tumor growth and metastasis and a major contributor to cancer-related mortality. Therefore, understanding the molecular mechanisms underlying tumor angiogenesis is of utmost importance. Numerous studies have documented the involvement of different types of non-coding RNAs in the regulation of angiogenesis. This review provides an overview of how non-coding RNAs regulate tumor angiogenesis. Additionally, we discuss emerging strategies that exploit non-coding RNAs for anti-angiogenic therapy in cancer treatment. Ultimately, this review underscores the crucial role played by non-coding RNAs in tumor angiogenesis and highlights their potential as therapeutic targets for anti-angiogenic interventions against cancer.

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.

Exploring the lncRNA-VEGF axis: Implications for cancer detection and therapy

Cancer is a complicated illness that spreads indefinitely owing to epigenetic, genetic, and genomic alterations. Cancer cell multidrug susceptibility represents a severe barrier in cancer therapy. As a result, creating effective therapies requires a better knowledge of the mechanisms driving cancer development, progress, and resistance to medications. The human genome is predominantly made up of long non coding RNAs (lncRNAs), which are currently identified as critical moderators in a variety of biological functions. Recent research has found that changes in lncRNAs are closely related to cancer biology. The vascular endothelial growth factor (VEGF) signalling system is necessary for angiogenesis and vascular growth and has been related to an array of health illnesses, such as cancer. LncRNAs have been identified to alter a variety of cancer-related processes, notably the division of cells, movement, angiogenesis, and treatment sensitivity. Furthermore, lncRNAs may modulate immune suppression and are being investigated as possible indicators for early identification of cancer. Various lncRNAs have been associated with cancer development and advancement, serving as cancer-causing or suppressing genes. Several lncRNAs have been demonstrated through research to impact the VEGF cascade, resulting in changes in angiogenesis and tumor severity. For example, the lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) has been shown to foster the formation of oral squamous cell carcinoma and the epithelial-mesenchymal transition by stimulating the VEGF-A and Notch systems. Plasmacytoma variant translocation 1 (PVT1) promotes angiogenesis in non-small-cell lung cancer by affecting miR-29c and boosting the VEGF cascade. Furthermore, lncRNAs regulate VEGF production and angiogenesis by interacting with multiple downstream signalling networks, including Wnt, p53, and AKT systems. Identifying how lncRNAs engage with the VEGF cascade in cancer gives beneficial insights into tumor biology and possible treatment strategies. Exploring the complicated interaction between lncRNAs and the VEGF pathway certainly paves avenues for novel ways to detect better accurately, prognosis, and cure cancers. Future studies in this area could open avenues toward the creation of innovative cancer therapy regimens that enhance the lives of patients.

The Talented LncRNAs: Meshing into Transcriptional Regulatory Networks in Cancer

As a group of diseases characterized by uncontrollable cell growth, cancer is highly multifaceted in how it overrides checkpoints controlling proliferation. Amongst the regulators of these checkpoints, long non-coding RNAs (lncRNAs) can have key roles in why natural biological processes go haywire. LncRNAs represent a large class of regulatory transcripts that can localize anywhere in cells. They were found to affect gene expression on many levels from transcription to mRNA translation and even protein stability. LncRNA participation in such control mechanisms can depend on cell context, with given transcripts sometimes acting as oncogenes or tumor suppressors. Importantly, the tissue-specificity and low expression levels of lncRNAs make them attractive therapeutic targets or biomarkers. Here, we review the various cellular processes affected by lncRNAs and outline molecular strategies they use to control gene expression, particularly in cancer and in relation to transcription factors.

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.

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.

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.

Construction of a Necroptosis-Related lncRNA Signature for Predicting Prognosis and Immune Response in Kidney Renal Clear Cell Carcinoma

Necroptosis is a new type of programmed cell death and involves the occurrence and development of various cancers. Moreover, the aberrantly expressed lncRNA can also affect tumorigenesis, migration, and invasion. However, there are few types of research on the necroptosis-related lncRNA (NRL), especially in kidney renal clear cell carcinoma (KIRC). In this study, we analyzed the sequencing data obtained from the TGCA-KIRC dataset, then applied the LASSO and COX analysis to identify 6 NRLs (AC124854.1, AL117336.1, DLGAP1-AS2, EPB41L4A-DT, HOXA-AS2, and LINC02100) to construct a risk model. Patients suffering from KIRC were divided into high- and low-risk groups according to the risk score, and the patients in the low-risk group had a longer OS. This signature can be used as an indicator to predict the prognosis of KIRC independent of other clinicopathological features. In addition, the gene set enrichment analysis showed that some tumor and immune-associated pathways were more enriched in a high-risk group. We also found significant differences between the high and low-risk groups in the infiltrating immune cells, immune functions, and expression of immune checkpoint molecules. Finally, we use the "pRRophetic" package to complete the drug sensitivity prediction, and the risk score could reflect patients' response to 8 small molecule compounds. In general, NRLs divided KIRC into two subtypes with different risk scores. Furthermore, this signature based on the 6 NRLs could provide a promising method to predict the prognosis and immune response of KIRC patients. To some extent, our findings helped give a reference for further research between NRLs and KIRC and find more effective therapeutic drugs for KIRC.

Integrated Analysis of the Role of Enolase 2 in Clear Cell Renal Cell Carcinoma

Enolase 2 (ENO2) has increasingly been documented in multiple cancers in recent years. However, the role of ENO2 in clear cell renal carcinoma (ccRCC) has not been fully explored. In the present study, open-access data were downloaded from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and the Human Protein Atlas (HPA) databases. All statistical analyses were performed in R and GraphPad Prism 8 softwares. Results showed that ENO2 was overexpressed in ccRCC tissues and cell lines and correlated with worse clinical features and prognosis. In vitro experiments indicated that the inhibition of ENO2 could hamper the malignant behaviors of ccRCC cells. Gene Set Enrichment Analysis showed that epithelial-mesenchymal transition, KRAS signaling, inflammatory response, angiogenesis, hypoxia, and WNT/β-catenin pathways were upregulated in the ENO2 high-expression group; whereas adipogenesis, DNA repair, and androgen response pathways were downregulated. Immune infiltration analysis indicated that patients with high ENO2 levels might have higher M2 macrophages and lower γβ T cells in the tumor microenvironment, which may account to some extent for the worse prognosis of ENO2. Moreover, it was found that patients with low and high ENO2 expression might be more sensitive to PD-1 therapy and CTLA-4 therapy, respectively. In addition, patients with high ENO2 expression showed lower sensitivity to common chemotherapy drugs for ccRCC, including axitinib, cisplatin, gemcitabine, pazopanib, sunitinib, and temsirolimus. Overall, these results suggest that ENO2 is a potential prognosis biomarker of ccRCC and could affect the malignant biological behavior of cancer cells, highlighting its value as a potential therapeutic target.

Overexpressed lncRNA FTX promotes the cell viability, proliferation, migration and invasion of renal cell carcinoma via FTX/miR‑4429/UBE2C axis

The present study aimed to explore the role of long non‑coding (lnc)RNA FTX and ubiquitin‑conjugating enzyme E2C (UBE2C) in promoting the progression of renal cell carcinoma (RCC) and the underlying regulatory mechanism. Relative levels of lncRNA FTX, UBE2C, AKT, CDK1 and CDK6 in RCC cell lines were detected by reverse transcription‑quantitative (RT‑q). Expression levels of UBE2C, phosphorylated (p)‑AKT/AKT, p‑CDK1/CDK1 and p‑CDK6/CDK6 in RCC and paracancerous specimens and RCC cells were measured by western blot or immunohistochemistry assay. In addition, the proliferative rate, cell viability, cell cycle progression, migratory rate and invasive rate of RCC cells overexpressing lncRNA FTX by lentivirus transfection were determined by a series of functional experiments, including the colony formation assay, MTT assay, flow cytometry, Transwell assay and wound healing assay. The targeted binding relationship in the lncRNA FTX/miR‑4429/UBE2C axis was validated by dual‑luciferase reporter assay. By intervening microRNA (miR)‑4492 and UBE2C by the transfection of miR‑4429‑mimics or short interfering UBE2C‑2, the regulatory effect of lncRNA FTX/miR‑4429/UBE2C axis on the progression of RCC was evaluated. Finally, a xenograft model of RCC in nude mice was established by subcutaneous implantation, thus evaluating the in vivo function of lncRNA FTX in the progression of RCC. The results showed that lncRNA FTX and UBE2C were upregulated in RCC specimens and cell lines. The overexpression of lncRNA FTX in RCC cells upregulated UBE2C. In addition, the overexpression of lncRNA FTX promoted the cell viability and proliferative, migratory and invasive capacities of RCC cells and accelerated the cell cycle progression. A dual‑luciferase reporter assay validated that lncRNA FTX exerted the miRNA sponge effect on miR‑4429, which was bound to UBE2C 3'UTR. Knockdown of UBE2C effectively reversed the regulatory effects of overexpressed lncRNA FTX on the abovementioned phenotypes of RCC cells. In the xenograft model of RCC, the mice implanted with RCC cells overexpressing lncRNA FTX showed a larger tumor size and higher tumor weight than those of controls, while the in vivo knockdown of UBE2C significantly reduced the size of RCC lesions, indicating the reversed cancer‑promoting effect of lncRNA FTX. Overall, the present study showed that lncRNA FTX was upregulated in RCC and could significantly promote the proliferative, migratory and invasive capacities, enhancing the viability and accelerating the cell cycle progression of RCC cells by exerting the miRNA sponge effect on miR‑4429 and thus upregulating UBE2C. lncRNA FTX and UBE2C are potential molecular biomarkers and therapeutic targets of RCC.

LncRNAs in the Regulation of Genes and Signaling Pathways through miRNA-Mediated and Other Mechanisms in Clear Cell Renal Cell Carcinoma

The fundamental novelty in the pathogenesis of renal cell carcinoma (RCC) was discovered as a result of the recent identification of the role of long non-coding RNAs (lncRNAs). Here, we discuss several mechanisms for the dysregulation of the expression of protein-coding genes initiated by lncRNAs in the most common and aggressive type of kidney cancer-clear cell RCC (ccRCC). A model of competitive endogenous RNA (ceRNA) is considered, in which lncRNA acts on genes through the lncRNA/miRNA/mRNA axis. For the most studied oncogenic lncRNAs, such as HOTAIR, MALAT1, and TUG1, several regulatory axes were identified in ccRCC, demonstrating a number of sites for various miRNAs. Interestingly, the LINC00973/miR-7109/Siglec-15 axis represents a novel agent that can suppress the immune response in patients with ccRCC, serving as a valuable target in addition to the PD1/PD-L1 pathway. Other mechanisms of action of lncRNAs in ccRCC, involving direct binding with proteins, mRNAs, and genes/DNA, are also considered. Our review briefly highlights methods by which various mechanisms of action of lncRNAs were verified. We pay special attention to protein targets and signaling pathways with which lncRNAs are associated in ccRCC. Thus, these new data on the different mechanisms of lncRNA functioning provide a novel basis for understanding the pathogenesis of ccRCC and the identification of new prognostic markers and targets for therapy.

A New Story of the Three Magi: Scaffolding Proteins and lncRNA Suppressors of Cancer

Scaffolding molecules exert a critical role in orchestrating cellular response through the spatiotemporal assembly of effector proteins as signalosomes. By increasing the efficiency and selectivity of intracellular signaling, these molecules can exert (anti/pro)oncogenic activities. As an archetype of scaffolding proteins with tumor suppressor property, the present review focuses on MAGI1, 2, and 3 (membrane-associated guanylate kinase inverted), a subgroup of the MAGUK protein family, that mediate networks involving receptors, junctional complexes, signaling molecules, and the cytoskeleton. MAGI1, 2, and 3 are comprised of 6 PDZ domains, 2 WW domains, and 1 GUK domain. These 9 protein binding modules allow selective interactions with a wide range of effectors, including the PTEN tumor suppressor, the β-catenin and YAP1 proto-oncogenes, and the regulation of the PI3K/AKT, the Wnt, and the Hippo signaling pathways. The frequent downmodulation of MAGIs in various human malignancies makes these scaffolding molecules and their ligands putative therapeutic targets. Interestingly, MAGI1 and MAGI2 genetic loci generate a series of long non-coding RNAs that act as a tumor promoter or suppressor in a tissue-dependent manner, by selectively sponging some miRNAs or by regulating epigenetic processes. Here, we discuss the different paths followed by the three MAGIs to control carcinogenesis.