lncRNA 00312 Attenuates Cell Proliferation and Invasion and Promotes Apoptosis in Renal Cell Carcinoma via miR-34a-5p/ASS1 Axis

Exosomes in renal cell carcinoma: challenges and opportunities

Renal cell carcinoma (RCC) is the most common type of kidney cancer that accounts for approximately 2-3% of adult malignancies. Among the primary treatment methods for this type of cancer are surgery and targeted treatment. Still, due to less than optimal effectiveness, there are problems such as advanced distant metastasis, delayed diagnosis, and drug resistance that continue to plague patients. In recent years, therapeutic advances have increased life expectancy and effective treatment in renal cell carcinoma patients. One of these methods is the use of stem cells. Although the therapeutic effects of stem cells, especially mesenchymal stem cells, are still impressive, today, extracellular vesicles (EVs) as carrying molecules and various mediators in intercellular communications, having a central role in tumorigenesis, metastasis, immune evasion, and drug response, and on the other hand, due to its low immunogenicity and strong regulatory properties of the immune system, has received much attention from researchers and doctors. Despite the increasing interest in exosomes as the most versatile type of EVs, the heterogeneity of their efficacy presents challenges and, on the other hand, exciting opportunities for diagnostic and clinical interventions.In the upcoming article, we will review the various aspects of exosomes' effects in the prevention, treatment, and progress of renal cell carcinoma and also ways to optimize them to strengthen their positive sides.

Amino acid metabolism regulated by lncRNAs: the propellant behind cancer metabolic reprogramming

Metabolic reprogramming is one of the main characteristics of cancer cells and plays pivotal role in the proliferation and survival of cancer cells. Amino acid is one of the key nutrients for cancer cells and many studies have focused on the regulation of amino acid metabolism, including the genetic alteration, epigenetic modification, transcription, translation and post-translational modification of key enzymes in amino acid metabolism. Long non-coding RNAs (lncRNAs) are composed of a heterogeneous group of RNAs with transcripts of more than 200 nucleotides in length. LncRNAs can bind to biological molecules such as DNA, RNA and protein, regulating the transcription, translation and post-translational modification of target genes. Now, the functions of lncRNAs in cancer metabolism have aroused great research interest and significant progress has been made. This review focuses on how lncRNAs participate in the reprogramming of amino acid metabolism in cancer cells, especially glutamine, serine, arginine, aspartate, cysteine metabolism. This will help us to better understand the regulatory mechanism of cancer metabolic reprogramming and provide new ideas for the development of anti-cancer drugs. Video Abstract.

Renal Cell Carcinoma as a Metabolic Disease: An Update on Main Pathways, Potential Biomarkers, and Therapeutic Targets

Clear cell renal cell carcinoma (ccRCC) is the most frequent histological kidney cancer subtype. Over the last decade, significant progress has been made in identifying the genetic and metabolic alterations driving ccRCC development. In particular, an integrated approach using transcriptomics, metabolomics, and lipidomics has led to a better understanding of ccRCC as a metabolic disease. The metabolic profiling of this cancer could help define and predict its behavior in terms of aggressiveness, prognosis, and therapeutic responsiveness, and would be an innovative strategy for choosing the optimal therapy for a specific patient. This review article describes the current state-of-the-art in research on ccRCC metabolic pathways and potential therapeutic applications. In addition, the clinical implication of pharmacometabolomic intervention is analyzed, which represents a new field for novel stage-related and patient-tailored strategies according to the specific susceptibility to new classes of drugs.

A new CCCH-type zinc finger-related lncRNA signature predicts the prognosis of clear cell renal cell carcinoma patients

Background: Clear cell renal cell carcinoma (ccRCC) is the main component of renal cell carcinoma (RCC), and advanced ccRCC frequently indicates a poor prognosis. The significance of the CCCH-type zinc finger (CTZF) gene in cancer has been increasingly demonstrated during the past few years. According to studies, targeted radical therapy for cancer treatment may be a revolutionary therapeutic approach. Both lncRNAs and CCCH-type zinc finger genes are essential in ccRCC. However, the predictive role of long non-coding RNA (lncRNA) associated with the CCCH-type zinc finger gene in ccRCC needs further elucidation. This study aims to predict patient prognosis and investigate the immunological profile of ccRCC patients using CCCH-type zinc finger-associated lncRNAs (CTZFLs).

Methods: From the Cancer Genome Atlas database, RNA-seq and corresponding clinical and prognostic data of ccRCC patients were downloaded. Univariate and multivariate Cox regression analyses were conducted to acquire CTZFLs for constructing prediction models. The risk model was verified using receiver operating characteristic curve analysis. The Kaplan-Meier method was used to analyze the overall survival (OS) of high-risk and low-risk groups. Multivariate Cox and stratified analyses were used to assess the prognostic value of the predictive feature in the entire cohort and different subgroups. In addition, the relationship between risk scores, immunological status, and treatment response was studied.

Results: We constructed a signature consisting of eight CTZFLs (LINC02100, AC002451.1, DBH-AS1, AC105105.3, AL357140.2, LINC00460, DLGAP1-AS2, AL162377.1). The results demonstrated that the prognosis of ccRCC patients was independently predicted by CTZFLs signature and that the prognosis of high-risk groups was poorer than that of the lower group. CTZFLs markers had the highest diagnostic adequacy compared to single clinicopathologic factors, and their AUC (area under the receiver operating characteristic curve) was 0.806. The overall survival of high-risk groups was shorter than that of low-risk groups when patients were divided into groups based on several clinicopathologic factors. There were substantial differences in immunological function, immune cell score, and immune checkpoint expression between high- and low-risk groups. Additionally, Four agents, including ABT737, WIKI4, afuresertib, and GNE 317, were more sensitive in the high-risk group.

Conclusion: The Eight-CTZFLs prognostic signature may be a helpful prognostic indicator and may help with medication selection for clear cell renal cell carcinoma.

Argininosuccinate synthase 1, arginine deprivation therapy and cancer management

Metabolic reprogramming is an emerging hallmark of tumor cells. In order to survive in the nutrient-deprived environment, tumor cells rewire their metabolic phenotype to provide sufficient energy and build biomass to sustain their transformed state and promote malignant behaviors. Amino acids are the main compositions of protein, which provide key intermediate substrates for the activation of signaling pathways. Considering that cells can synthesize arginine via argininosuccinate synthase 1 (ASS1), arginine is regarded as a non-essential amino acid, making arginine depletion as a promising therapeutic strategy for ASS1-silencing tumors. In this review, we summarize the current knowledge of expression pattern of ASS1 and related signaling pathways in cancer and its potential role as a novel therapeutic target in cancer. Besides, we outline how ASS1 affects metabolic regulation and tumor progression and further discuss the role of ASS1 in arginine deprivation therapy. Finally, we review approaches to target ASS1 for cancer therapies.

Regulatory mechanisms and potential medical applications of HNF1A-AS1 in cancers

Long noncoding RNAs (lncRNAs) are defined as a class of non-protein-coding RNAs that are longer than 200 nucleotides. Previous studies have shown that lncRNAs play a vital role in the progression of multiple diseases, which highlights their potential for medical applications. The lncRNA hepatocyte nuclear factor 1 homeobox A (HNF1A) antisense RNA 1 (HNF1A-AS1) is known to be abnormally expressed in multiple cancers. HNF1A-AS1 exerts its oncogenic roles through a variety of molecular mechanisms. Moreover, aberrant HNF1A-AS1 expression is associated with diverse clinical features in cancer patients. Therefore, HNF1A-AS1 is a promising biomarker for tumor diagnosis and prognosis and thus a potential candidate for tumor therapy. This review summarizes current studies on the role and the underlying mechanisms of HNF1A-AS1 various cancer types, including gastric cancer, liver cancer, glioma, lung cancer, colorectal cancer, breast cancer, bladder cancer, osteosarcoma, esophageal adenocarcinoma, hemangioma, oral squamous cell carcinoma, laryngeal squamous cell carcinoma, cervical cancer, as well as gastroenteropancreatic neuroendocrine neoplasms. We also describe the diagnostic, prognostic, and therapeutic value of HNF1A-AS1 for multiple cancer patients.

A Prognostic Signature for Clear Cell Renal Cell Carcinoma Based on Ferroptosis-Related lncRNAs and Immune Checkpoints

Background: Ferroptosis is a potential target for cancer therapy, and lncRNAs can also affect ferroptosis by regulating related genes. The pathogenesis of clear cell renal cell carcinoma (ccRCC) regarding the regulation of ferroptosis by lncRNAs is still unknown.

Methods: We constructed a risk model based on data in ccRCC patients obtained from the TCGA database and validated the diagnostic and prognostic value of the model. In addition, immune function and immune checkpoint variability analysis validated the association of ferroptosis with ccRCC tumor immunity.

Results: The characteristics of ferroptosis-related lncRNAs (FRLs) were significantly correlated with the prognosis of ccRCC patients. The prognostic characteristics of FRLs were independent prognostic factors in ccRCC patients. Gene function in the high-risk group was associated with oxygen metabolic processes and immune pathways. Immune checkpoint variability analysis showed that HAVCR2, NRP1, and HHLA2 were upregulated in the low-risk group, while CD44, TNFRSF18, TNFSF14, TNFRSF8, CD276, and TNFRSF25 were upregulated in the high-risk group.

Conclusions: The prognostic characteristics of FRLs can effectively predict the prognosis of ccRCC patients and provide a new direction for clinical treatment.

PGAM1 regulation of ASS1 contributes to the progression of breast cancer through the cAMP/AMPK/CEBPB pathway

Phosphoglycerate mutase 1 (PGAM1) is a crucial glycolytic enzyme, and its expression status has been confirmed to be associated with tumor progression and metastasis. However, the precise role and other biological functions of PGAM1 remain unclear. Here, we report that PGAM1 expression is upregulated and related to poor prognosis in patients with breast cancer (BC). Functional experiments showed that knockdown of PGAM1 could suppress the proliferation, invasion, migration, and epithelial–mesenchymal transition of BC cells. Through RNA sequencing, we found that argininosuccinate synthase 1 (ASS1) expression was markedly upregulated in BC cells following PGAM1 knockdown, and it is required to suppress the malignant biological behavior of BC cells. Importantly, we demonstrated that PGAM1 negatively regulates ASS1 expression through the cAMP/AMPK/CEBPB axis. In vivo experiments further validated that PGAM1 promoted tumor growth in BC by altering ASS1 expression. Finally, immunohistochemical analysis showed that downregulated ASS1 levels were associated with PGAM1 expression and poor prognosis in patients with BC. Our study provides new insight into the regulatory mechanism of PGAM1‐mediated BC progression that might shed new light on potential targets and combination therapeutic strategies for BC treatment.

Effects of IncRNA PROX1-AS1 on Proliferation, Migration, Invasion and Apoptosis of Lung Cancer Cells by Regulating MiR-1305

This paper aims to explore the lncRNA PROX1-AS1 effect on proliferation, migration, invasion, and apoptosis of lung cancer cells together with its targeted regulation on miR-1305. To adopt qRT-PCR to test PROX1-AS1 and miR-1305 expression levels in lung cancer tissues and adjacent tissues. Lung cancer cells A549 were cultured in vitro and randomly divided into several groups, which are si-NC, si-PROX1-AS1, miR-NC, miR-1305, si-PROX1-AS1 plus anti-miR-NC, and si-PROX1-AS1 plus anti-miR-1305. To adopt the CCK-8 method to test cell proliferation and to adopt the Transwell chamber experiment to test cell migration and invasion. To adopt the flow cytometry method to test the apoptosis rate. Through a dual luciferase experiment, we decided to find out the targeting relationship between PROX1-AS1 and miR-1305. Then we adopted the western blot method to test CyclinD1, MMP-2, MMP-9, Bcl-2, p21, and Bax expression levels. Compared with adjacent tissues (P < 0.05), the expression of PROX1-AS1 in lung cancer tissue was remarkably higher, while the expression of miR-1305 was remarkably lower (P < 0.05). After PROX1-AS1 knockdown expression or miR-1305 overexpression, cell activity, migration, and invasion ability were outstandingly lowered (P < 0.05), but the apoptosis rate was obviously raised (P < 0.05), CyclinD1, MMP-2, Bcl-2, and MMP-9 protein data were remarkably reduced (P < 0.05), but p21 and Bax protein conditions were outstandingly enhanced (P < 0.05). The dual luciferase experiment confirmed that PROX1-AS1 had a targeting relationship with miR-1305. After cotransfection with si-PROX1-AS1 and anti-miR-1305, the cell viability, migration and invasion ability were remarkably enhanced (P < 0.05), the apoptosis rate was remarkably reduced (P < 0.05), CyclinD1, MMP-2, Bcl-2, and MMP-9 protein were increased remarkably (P < 0.05), and p21 or Bax protein was lowered remarkably (P < 0.05). On the one hand, PROX1-AS1 can promote lung cancer proliferation, migration, and invasion. On the other hand, it may restrain apoptosis, possibly through inhibiting miR-1305 expression.

N(6)-adenosine-methyltransferase-14 promotes glioma tumorigenesis by repressing argininosuccinate synthase 1 expression in an m6A-dependent manner

Glioma is one of the leading causes of tumor-related deaths worldwide, but its potential mechanism remains unclear. This study aimed to explore the biological role and potential mechanism of argininosuccinate synthase 1 (ASS1) in glioma. The relative expression levels of ASS1 in glioma specimens and cell lines were calculated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting. The biological functions of ASS1 were demonstrated using the 5-ethynyl-2'-deoxyuridine (EdU) assay, transwell assay, and in vivo experiments. In addition, methylated RNA immunoprecipitation (MeRIP), RNA immunoprecipitation (RIP), and luciferase reporter assays were performed to explore the molecular mechanism of ASS1 in glioma. ASS1 expression levels were found to be downregulated in glioma specimens and cell lines. Functionally, we confirmed that ASS1 inhibited glioma cell proliferation, migration, invasion, and growth both. Furthermore, we found that ASS1 was a target of N(6)-adenosine-methyltransferase-14 (METTL14)-mediated N6-methyladenosine (m6A) modification. Overexpression of METTL14 markedly elevated ASS1 mRNA m6A modification and suppressed ASS1 mRNA expression. We also revealed that METTL14-mediated ASS1 mRNA degradation relied on the YTH m6A RNA-binding protein 2 (YTHDF2)-dependent pathway. We confirmed that decreased ASS1 expression promoted the cell proliferation, migration, and invasion in glioma, and that the METTL14/ASS1/YTHDF2 regulatory axis may be an effective therapeutic target for glioma.

E2F transcription factor 1/small nucleolar RNA host gene 18/microRNA-338-5p/forkhead box D1: an important regulatory axis in glioma progression

This study aims to probe the biological functions of long non-coding RNA small nucleolar RNA host gene 18 (SNHG18) on glioma cells and its underlying mechanism. In this study, SNHG18 expression in glioma tissues was quantified employing GEPIA database; quantitative real-time PCR was adopted to examine the expressions of SNHG18, microRNA-338-5p (miR-338-5p) and forkhead box D1 (FOXD1) mRNA in glioma tissues and cell lines; cell proliferation, migration and invasion were detected utilizing cell counting kit-8, EdU and Transwell assays; Western blot was utilized to quantify the protein expressions of E-cadherin, N-cadherin, Vimentin and FOXD1; dual-luciferase reporter gene and RNA immunoprecipitation experiments were utilized to validate the targeting relationships between SNHG18 and miR-338-5p, as well as miR-338-5p and FOXD1 mRNA 3ʹUTR; dual-luciferase reporter gene and chromatin immunoprecipitation assays were utilized to verify the binding of E2F transcription factor 1 (E2F1) to the SNHG18 promoter region. It was revealed that, SNHG18 expression in glioma was up-regulated and associated with unfavorable prognosis of the patients; knockdown of SNHG18 repressed the malignant biological behaviors of glioma cells, enhanced E-cadherin expression and repressed N-cadherin and Vimentin expressions. MiR-338-5p was a target of SNHG18, and SNHG18 promoted the expression of FOXD1 by decoying miR-338-5p. Additionally, E2F1 could bind to the promoter of SNHG18 to elevate its expression. In conclusion, SNHG18 accelerates glioma progression via regulating the miR-338-5p/FOXD1 axis.

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.

circAMOTL1L Suppresses Renal Cell Carcinoma Growth by Modulating the miR-92a-2-5p/KLLN Pathway

Accumulating evidence indicates that the dysregulation of circular RNAs (circRNAs) contributes to tumor progression; however, the regulatory functions of circRNAs in renal cell carcinoma (RCC) remain largely unknown. In this study, the function and underlying mechanism of circAMOTL1L in RCC progression were explored. qRT-PCR showed the downregulation of circAMOTL1L in RCC tissues and cell lines. The decrease in circAMOTL1L expression correlated with the tumor stage, metastasis, and poor prognosis in patients with RCC. Functional experiments revealed that circAMOTL1L inhibited cell proliferation and increased apoptosis in RCC cells. Subcutaneous implantation with circAMOTL1L-overexpressing cells in nude mice decreased the growth ability of the xenograft tumors. Mechanistically, circAMOTL1L served as a sponge for miR-92a-2-5p in upregulating KLLN (killin, p53-regulated DNA replication inhibitor) expression validated by bioinformatics analysis, oligo pull-down, and luciferase assays. Further, reinforcing the circAMOTL1L-miR-92a-2-5p-KLLN axis greatly reduced the growth of RCC in vivo. Conclusively, our findings demonstrate that circAMOTL1L has an antioncogenic role in RCC growth by modulating the miR-92a-2-5p-KLLN pathway. Thus, targeting the novel circAMOTL1L-miR-92a-2-5p-KLLN regulatory axis might provide a therapeutic strategy for RCC.

LncRNA SNHG17 promotes tumor progression and predicts poor survival in human renal cell carcinoma via sponging miR-328-3p

Accumulating data shows that dysregulation of long non-coding RNAs (lncRNAs) are involved in human tumors' occurrence and progression. Small nucleolar RNA host genes (SNHGs) are recently revealed to play a carcinogenic role in various human neoplasms. However, the functions and underlying mechanisms of lncRNA SNHG17 in renal cell carcinoma (RCC) are still elusive. We analyzed the relationship between SNHG17 expression levels and clinicopathologic characteristics and prognosis in patients with RCC according to TCGA RNA-sequencing data and our cohort data. Loss-of-function and gain-of-function experiments were conducted to examine the biological behaviors of SNHG17 on RCC cell proliferation, migration, invasion, apoptosis, and tumor growth in vivo. The interaction between SNHG17, miR-328-3p, and Histone’sH2Avariant (H2AX) was verified by bioinformatics, dual-luciferase reporter gene, and RNA immunoprecipitation (RIP). Highly expressed SNHG17 was evident in RCC tissue samples and cell lines, and SNHG17 overexpression was related to advanced TNM stage and reduced relapse-free and overall survival of patients with RCC. Knockdown of SNHG17 prohibited malignant phenotypes, whereas ectopic SNHG17 expression showed the opposite effects. More importantly, SNHG17 could upregulate the expression of H2AX by acting as a miR-328-3p sponge. In vivo experiments confirmed that SNHG17 promoted the growth of RCC tumors. SNHG17/miR-328-3p/H2AXaxis might be involved in RCC progression, which provided a potential therapeutic target for RCC.

The LINC01260 Functions as a Tumor Suppressor via the miR-562/CYLD/NF-κB Pathway in Non-Small Cell Lung Cancer

PURPOSE

Recently, long noncoding RNAs (lncRNAs) have been identified as novel and potential therapeutic targets in various cancer types. Nonetheless, the levels and biological effects of lncRNAs in non-small cell lung cancer (NSCLC) remain largely unknown. In this study, we aimed to identify the effects of lncRNA-LINC01260 throughout the progression of NSCLC and explore the underlying mechanism.

METHODS

Quantitative real-time PCR (qRT-PCR) and Western blot were performed to measure LINC01260, miR-562, and CYLD expression and protein levels. Luciferase reporter assay was employed to investigate the relationship between LINC01260 and miR-562, and miR-562 and CYLD, respectively. The viability and migration of cells were evaluated using CCK-8, colony formation, and transwell assays. The effects of LINC01260 were identified through tumorigenesis in vivo. ELISA was performed to detect the activity of NF-κB and p65 expression.

RESULTS

In NSCLC tissues and cell lines, LINC01260 expression was downregulated, which corresponded to a lower survival rate of patients with NSCLC. Knockdown of LINC01260 accelerated the proliferation, colony formation, and migration of NSCLC cells. Moreover, downregulation of LINC01260 inhibited apoptosis of NSCLC cells by regulating the expression of Bcl-2 and Bax proteins in vitro. In vivo, the downregulation of LINC01260 promoted tumor growth. miR-562 was identified as the target gene of LINC01260, which was upregulated in NSCLC tumors. Furthermore, CYLD was identified as the target gene of miR-562. The effects of LINC01260 were exerted by regulating CYLD via sponging miR-562. ELISA confirmed that the upregulation of CYLD inhibited NF-κB activity; however, the co-transfection of sh-LINC01260 partly reversed the inhibition. Additionally, CYLD reduced p65 expression; however, downregulation of LINC01260 slightly increased the expression level.

CONCLUSION

This study revealed a novel LINC01260/miR-562/CYLD/NF-κB pathway in the pathogenesis of NSCLC and suggested a potential therapeutic target for NSCLC.

Long noncoding RNA SNHG4 promotes renal cell carcinoma tumorigenesis and invasion by acting as ceRNA to sponge miR-204-5p and upregulate RUNX2

Background

Long noncoding RNAs (lncRNAs) are involved in the tumorigenesis and progression of human cancers, including renal cell carcinoma (RCC). Small nucleolar RNA host gene 4 (SNHG4) is reported to play an essential role in tumor growth and progression. However, the molecular mechanisms and function of SNHG4 in RCC remain undocumented.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to examine expression levels of SNHG4 in RCC tissue samples and cell lines. Cell counting kit-8, western blotting, activities of caspase-3, -8, and -9, wound-healing, and transwell invasion assays were performed to explore cell proliferation, apoptosis, migration, and invasion. The interaction among SNHG4, miR-204-5p, and RUNX2 was verified by bioinformatic analysis, a luciferase gene report, qRT-PCR, western blot analysis, and RNA immunoprecipitation assays. Xenograft mouse models were carried out to examine the role of SNHG4 in RCC in vivo.

Results

SNHG4 was highly expressed in RCC tissue samples and cell lines, and its upregulation was significantly involved in node involvement, distant metastasis, and reduced overall and relapse-free survival of patients with RCC. SNHG4 acted as an oncogenic lncRNA with promoted RCC cell proliferation, migration, invasion, and inhibited apoptosis. SNHG4 boosted tumor growth in xenograft mouse models. Mechanistically, SNHG4 functioned as a competing endogenous RNA (ceRNA) for sponging miR-204-5p, leading to the upregulation of its target RUNX2 to promote RCC cell proliferation and invasion.

Conclusion

SNHG4 and miR-204-5p might be indicated in RCC progression via RUNX2, suggesting the potential use of SNHG4/miR-204-5p/RUNX2 axis in RCC treatment.