Circ_0009910 sponges miR-491-5p to promote acute myeloid leukemia progression through modulating B4GALT5 expression and PI3K/AKT signaling pathway

Ginsenoside 20(S)-Rg3 Hinders Esophageal Squamous Cell Carcinoma Cells Malignant Behaviors by miR-210-3p/B4GALT5 Axis

Ginsenoside 20(S)-Rg3 (20(S)-Rg3) belongs to a natural chemical with an anti-tumor function, but its potential function and underlying mechanism in esophageal squamous cell carcinoma (ESCC) are unknown. Several reports have manifested that microRNA (miRNA) miR-210-3p functions as a tumor repressor in tumors, but its biofunction in ESCC remains obscure. Herein, the role and interaction of 20(S)-Rg3 and miR-210-3p in ESCC cells were investigated. We performed a series of functional experiments to validate that 20(S)-Rg3 notably restrained ESCC cell proliferation and migration while promoting cell apoptosis. Besides, miR-210-3p was found to be lowly expressed in ESCC cells. Overexpressing miR-210-3p suppressed the malignant behaviors of ESCC cells. More importantly, 20(S)-Rg3 could upregulate miR-210-3p expression in ESCC cells. MiR-210-3p knockdown offset the inhibitive impacts of 20(S)-Rg3 treatment on ESCC cell growth and migration. Furthermore, through luciferase reporter assay, beta-1,4-galactosyltransferase 5 (B4GALT5) was certified to be targeted by miR-210-3p. B4GALT5 upregulation neutralized the suppressive function of 20(S)-Rg3 on ESCC progression. Overall, 20(S)-Rg3 attenuated malignant behaviors of ESCC cells by modulating miR-210-3p/B4GALT5 axis, indicating 20(S)-Rg3 has therapeutic potential for ESCC.

Prognostic value of circular RNAs expression and their correlation with clinicopathological features in acute myeloid leukemia: a systematic review and meta-analysis

Acute myeloid leukemia (AML) prognosis is affected by unique factors to each individual and studies have indicated that dysregulated expression of circRNAs may serve as prognostic biomarkers for AML. Therefore, we conducted this study to assess the prognostic value of circRNAs expression and it's correlation with clinicopathological features. Comprehensive search was conducted in WOS, Scopus, PubMed, Google Scholar, ProQuest, and grey literature. The certainty of evidence was assessed using the modified GRADE approach for prognostic and clinicopathological meta-analysis. The hazard ratio (HR) was employed to assess the prognostic value of dysregulated expression of circRNAs in patient survival, while the risk ratio (RR) was utilized to analyze the correlation between circRNAs and clinicopathological features. Our results demonstrated that dysregulation of circRNAs expression was associated with poor prognosis related to overall survival (OS) indicator (HR:2.05; 95%CI: 1.75-2.40) and also related to non-OS indicators such as (EFS, LFS, RFS, and DFS) (HR:2.09, 95%CI: 1.47-2.97). Priori and post-hoc subgroup analysis was conducted to describe variables that potentially affected heterogeneity and effect size. We also evaluated the association between dysregulated expression of circRNAs and 19 clinicopathological parameters. Our results show that there is significant relationship between the dysregulated expression of circRNAs and the mentioned parameters: type M6 vs. other types (RR:1.51, 95% CI:1.12-2.03), FLT3-ITD mutation (RR:1.17, 95%CI: 1.00-1.36), and risk status (RR:1.35, 95% CI: 1.13-1.60). This systematic review and meta-analysis suggest that the investigation of circRNAs expression changes can serve as valuable biomarkers for the assessment of prognosis in AML patients.

The increase in the expression of circRNAs may contributes to a poor prognosis in acute myeloid leukemia: A systematic review and meta-analysis

OBJECTIVE

The primary methods for defining the prognostic risk of AML patients are cytogenetic and molecular analysis at the time of diagnosis. However, the prognosis of intermediate-risk patients is still not well assessed for biomarkers. The main objective of this meta-analysis is to evaluate the relationship between circRNAs and AML prognosis, to provide a theoretical basis for finding effective prognostic indicators in intermediate-risk patients, and to provide an important scientific basis for the development or revision of WHO practice guidelines and ELN risk classification, and to highlight the importance of continuing to focus on and evaluate the prognostic impact of circRNAs on AML in future studies.

METHODS

We performed a comprehensive literature search across PubMed, the Cochrane Library, and Web of Science databases for studies published up to September 15, 2024. Articles were selected based on inclusion criteria. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of studies. The outcome measure of overall survival (OS) was used, and hazard ratios (HR) and 95 % confidence intervals (CI) were pooled to estimate the relationship between circRNA expression and prognosis in AML using STATA 17.0 software.

RESULTS

A total of 13 studies involving 1401 AML patients were included. The studies showed a significantly increased hazard ratio (HR) of upregulated CircRNA expression for OS (HR=1.87, 95 % CI=1.51-2.32, P < 0.001). The results of subgroups analysis showed a significant increase in the hazard ratio (HR) for upregulation of CircRNA expression in EFS and circ_0012152（HR= 1.66, 95 % CI= 1.19-2.32, P < 0.005 and HR= 2.26,95 % CI= 1.27-4.00, P < 0.005), respectively. No significant heterogeneity or publication bias was detected.

CONCLUSION

Upregulated circRNA expression is significantly associated with poor prognosis in AML patients and may serve as a prognostic marker for AML.

Immune checkpoints and ncRNAs: pioneering immunotherapy approaches for hematological malignancies

Hematological malignancies are typically treated with chemotherapy and radiotherapy as the first-line conventional therapies. However, non-coding RNAs (ncRNAs) are a rapidly expanding field of study in cancer biology that influences the growth, differentiation, and proliferation of tumors by targeting immunological checkpoints. This study reviews the results of studies (from 2012 to 2024) that consider the immune checkpoints and ncRNAs in relation to hematological malignancies receiving immunotherapy. This article provides a summary of the latest advancements in immunotherapy for treating hematological malignancies, focusing on the role of immune checkpoints and ncRNAs in the immune response and their capacity for innovative strategies. The paper also discusses the function of immune checkpoints in maintaining immune homeostasis and how their dysregulation can contribute to developing leukemia and lymphoma. Finally, this research concludes with a discussion on the obstacles and future directions in this rapidly evolving field, emphasizing the need for continued research to fully harness the capacity of immune checkpoints and ncRNAs in immunotherapy for hematological malignancies.

The suppression of OTUD7B by miR-491-5p enhances the ubiquitination of VEGFA to suppress vascular mimicry in non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) is the main type of lung cancer with high morbidity and mortality. Vascular mimicry (VM), a distinct microcirculation model in tumors that differs from classical angiogenesis, is strongly associated with poor clinical outcomes in cancer patients. miR-491-5p has been reported to prevent NSCLC progression, including proliferation, metastasis, and angiogenesis. However, the effect and mechanism of miR-491-5p on VM have not been studied in NSCLC.

METHODS

The expression of miR-491-5p was detected by quantitative reverse transcription PCR (qPCR) and fluorescence in situ hybridization (FISH). Cell counting kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) staining assays were used to examine cell growth. Tube formation assay was used to assess VM in NSCLC cells. Immunohistochemistry (IHC) and western blot were performed to detect protein expression. Immunoprecipitation was used to confirm the interaction between OTU deubiquitinase 7B (OTUD7B) and vascular endothelial growth factor A (VEGFA), and the level of ubiquitinated VEGFA. A nude mouse tumorigenesis model was used to evaluate the carcinogenic capacity of NSCLC cells in vivo. Luciferase reporter assay was used to identify the potential target of miR-491-5p.

RESULTS

MiR-491-5p was found downregulated in NSCLC tissues, and miR-491-5p deficiency was strongly associated with angiogenesis. miR-491-5p mimics suppressed cell viability, migration, and VM. Conversely, an inhibitor of miR-491-5p had the opposite effect. OTUD7B, a deubiquitinase, was identified as a downstream target of miR-491-5p. A luciferase reporter assay indicated that miR-491-5p directly binds to the 3'UTR of OTUD7B. Moreover, mimics of miR-491-5p caused a significant reduction in the OTUD7B protein in NSCLC cells, and an inhibitor of miR-491-5p stabilized the OTUD7B protein. In addition, overexpression of OTUD7B promoted cell proliferation, migration, and VM, similar to the effects of an inhibitor of miR-491-5p. Further exploration revealed that OTUD7B interacts with VEGFA and that the miR-491-5p-OTUD7B axis modulates the ubiquitination of VEGFA. The rescue experiment indicated that OTUD7B compromised the inhibitory effects of miR-491-5p on the cellular function of NSCLC cells.

CONCLUSIONS

Overall, our study first proved that miR-491-5p impedes VM by suppressing OUTD7B and promoting the ubiquitination of VEGFA. The miR-491-5p/OTUD7B axis may be a novel target for antiangiogenic therapy in NSCLC.

Circular RNA as Diagnostic and Prognostic Biomarkers in Hematological Malignancies:Systematic Review

Objectives: While various serum and tissue biomarkers have been explored for tumor diagnosis, the sensitivity and specificity have not yield optimal results. Circular RNAs (circRNAs) are more stable, conserved, and tissue-specific than linear RNA. Recent reports indicate that circRNAs could serve as potential biomarkers in the diagnosis or/and prognosis of tumors. In this study, we systematically examined the relationship between circRNA expression and diagnostic and prognostic outcomes in patients with hematological tumors. Methods: We searched several databases, including Google Scholar, MEDLINE, Scopus, PubMed, Embase, ScienceDirect, Ovid-Medline, Chinese National Knowledge Infrastructure, WanFang and SinoMed, with a cutoff date of June 12, 2024. The study protocol was PROSPERO (CRD42020188627). Result: A total of 73 studies were included in our review, comprising 39 diagnostic studies and 65 prognostic studies. Clinical parameters were assessed based on pooled adds ratios and 95% confidence intervals (CIs). Overall survival (OS) was evaluated using hazard ratios (HRs) and 95% CIs. The pooled area under the curve was 0.86, indicating the potential to identify hematological tumor patients, with sensitivity and specificity of 79% each. The diagnostic score for circRNAs related to hematological malignancies was 2.12. Notably, different hematological malignancies subgroups displayed varying prognoses. Specifically, lymphoid leukemia circRNA showed a negative impacct on prognosis (HR = 1.25, 95% CI: 1.10-1.43, P < 0.001). Conclusion: Our findings provide compelling evidence that circRNA may be serve as a promising alternative for the diagnosis and prognosis of hematological tumors.

New insight into circRNAs: characterization, strategies, and biomedical applications

Circular RNAs (circRNAs) are a class of covalently closed, endogenous ncRNAs. Most circRNAs are derived from exonic or intronic sequences by precursor RNA back-splicing. Advanced high-throughput RNA sequencing and experimental technologies have enabled the extensive identification and characterization of circRNAs, such as novel types of biogenesis, tissue-specific and cell-specific expression patterns, epigenetic regulation, translation potential, localization and metabolism. Increasing evidence has revealed that circRNAs participate in diverse cellular processes, and their dysregulation is involved in the pathogenesis of various diseases, particularly cancer. In this review, we systematically discuss the characterization of circRNAs, databases, challenges for circRNA discovery, new insight into strategies used in circRNA studies and biomedical applications. Although recent studies have advanced the understanding of circRNAs, advanced knowledge and approaches for circRNA annotation, functional characterization and biomedical applications are continuously needed to provide new insights into circRNAs. The emergence of circRNA-based protein translation strategy will be a promising direction in the field of biomedicine.

The non-coding competing endogenous RNAs in acute myeloid leukemia: biological and clinical implications

Acute myeloid leukemia (AML) is a hematologic carcinoma that has seen a considerable improvement in patient prognosis because of genetic diagnostics and molecularly-targeted therapies. Nevertheless, recurrence and drug resistance remain significant obstacles to leukemia treatment. It is critical to investigate the underlying molecular mechanisms and find solutions. Non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), circular RNAs, long non-coding RNAs, and pseudogenes, have been found to be crucial components in driving cancer. The competing endogenous RNA (ceRNA) mechanism has expanded the complexity of miRNA-mediated gene regulation. A great deal of literature has shown that ncRNAs are essential to the biological functions of the ceRNA network (ceRNET). NcRNAs can compete for the same miRNA response elements to influence miRNA-target RNA interactions. Recent evidence suggests that ceRNA might be a potential biomarker and therapeutic strategy. So far, however, there have been no comprehensive studies on ceRNET about AML. What is not yet clear is the clinical application of ceRNA in AML. This study attempts to summarize the development of research on the related ceRNAs in AML and the roles of ncRNAs in ceRNET. We also briefly describe the mechanisms of ceRNA and ceRNET. What's more significant is that we explore the clinical value of ceRNAs to provide accurate diagnostic and prognostic biomarkers as well as therapeutic targets. Finally, limitations and prospects are considered.

Circadian Genes MBOAT2/CDA/LPCAT2/B4GALT5 in the Metabolic Pathway Serve as New Biomarkers of PACA Prognosis and Immune Infiltration

Pancreatic cancer (PACA) is a highly malignant tumor with a poor prognosis. Recent studies have discovered substantial differences in the expression levels of several circadian genes in PACA samples compared to normal samples. The goal of this research was to find differentially expressed rhythm genes (DERGs) in PACA samples and determine their role in the development of PACA. A total of 299 DERGs were identified in PACA, including 134 downregulated genes and 165 upregulated genes. DERGs were significantly abundant in the metabolic pathway and immune response pathways, according to GO and KEGG analyses. Survival analyses showed that PACA patients who had higher expression levels of MBOAT2/CDA/LPCAT2/B4GALT5 had shorter overall survival times. Using cell assay verification, the mRNA levels of MBOAT2/CDA/LPCAT2/B4GALT5 in Patu-8988 and PNAC-1 cells were found to be significantly higher than those in HPDE6-C7 cells, which was in line with previous studies on PACA patient data. Through conducting univariate Cox analysis, it was determined that MBOAT2/CDA/LPCAT2/B4GALT5 expression, age and grade were all high-risk factors. The MBOAT2/CDA/LPCAT2/B4GALT5 genes were independently correlated with overall survival, according to the multivariate Cox analysis. The proportion of immune cells in PACA and normal samples significantly changed, according to the immune infiltration analysis. Furthermore, MBOAT2/CDA/LPCAT2/B4GALT5 expression levels were significantly related to the level of immune cell infiltration. The protein-protein interaction network of the MBOAT2/CDA/LPCAT2/B4GALT5 genes included 54 biological nodes and 368 interacting genes. In conclusion, the finding of these DERGs adds to the investigation of the molecular processes underlying the onset and progression of PACA. In the future, DERGs may serve as prognostic and diagnostic biomarkers as well as drug targets for chronotherapy in PACA patients.

Convenient and Sensitive Measurement of Lactosylceramide Synthase Activity Using Deuterated Glucosylceramide and Mass Spectrometry

Lactosylceramide is necessary for the biosynthesis of almost all classes of glycosphingolipids and plays a relevant role in pathways involved in neuroinflammation. It is synthesized by the action of galactosyltransferases B4GALT5 and B4GALT6, which transfer galactose from UDP-galactose to glucosylceramide. Lactosylceramide synthase activity was classically determined in vitro by a method based on the incorporation of radiolabeled galactose followed by the chromatographic separation and quantitation of the product by liquid scintillation counting. Here, we used deuterated glucosylceramide as the acceptor substrate and quantitated the deuterated lactosylceramide product by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). We compared this method with the classical radiochemical method and found that the reactions have similar requirements and provide comparable results in the presence of high synthase activity. Conversely, when the biological source lacked lactosylceramide synthase activity, as in the case of a crude homogenate of human dermal fibroblasts, the radiochemical method failed, while the other provided a reliable measurement. In addition to being very accurate and sensitive, the proposed use of deuterated glucosylceramide and LC-MS/MS for the detection of lactosylceramide synthase in vitro has the relevant advantage of avoiding the costs and discomforts of managing radiochemicals.

Circular RNAs and Untranslated Regions in Acute Myeloid Leukemia

Before the advent of next-generation sequencing, research on acute myeloid leukemia (AML) mostly centered on protein-coding genes. In recent years, breakthroughs in RNA sequencing technologies and whole transcriptome analysis have led to the discovery that approximately 97.5% of the human genome is transcribed into non-coding RNAs (ncRNAs). This paradigm shift has led to an explosion of research interest in different classes of non-coding RNAs, such as circular RNAs (circRNAs) as well as non-coding untranslated regions (UTRs) of protein-coding messenger RNAs. The critical roles of circRNAs and UTRs in AML pathogenesis have become increasingly apparent. In this review, we discuss the cellular mechanisms of circRNAs and summarize recent studies that reveal their biological roles in AML. Furthermore, we also review the contribution of 3'UTRs to disease progression. Finally, we discuss the potential of circRNAs and 3'UTRs as new biomarkers for disease stratification and/or the prediction of treatment response and targets for the development of RNA-directed therapeutic applications.

Circular RNAs: pivotal role in the leukemogenesis and novel indicators for the diagnosis and prognosis of acute myeloid leukemia

Acute myeloid leukemia (AML) is an aggressive hematological malignancy and affected patients have poor overall survival (OS) rates. Circular RNAs (circRNAs) are a novel class of non-coding RNAs (ncRNAs) with a unique loop structure. In recent years, with the development of high-throughput RNA sequencing, many circRNAs have been identified exhibiting either up-regulation or down-regulation in AML patients compared with healthy controls. Recent studies have reported that circRNAs regulate leukemia cell proliferation, stemness, and apoptosis, both positively and negatively. Additionally, circRNAs could be promising biomarkers and therapeutic targets in AML. In this study, we present a comprehensive review of the regulatory roles and potentials of a number of dysregulated circRNAs in AML.

The Mutual Relationship between Glycosylation and Non-Coding RNAs in Cancer and Other Physio-Pathological Conditions

Glycosylation, which consists of the enzymatic addition of sugars to proteins and lipids, is one of the most important post-co-synthetic modifications of these molecules, profoundly affecting their activity. Although the presence of carbohydrate chains is crucial for fine-tuning the interactions between cells and molecules, glycosylation is an intrinsically stochastic process regulated by the relative abundance of biosynthetic (glycosyltransferases) and catabolic (glycosidases) enzymes, as well as sugar carriers and other molecules. Non-coding RNAs, which include microRNAs, long non-coding RNAs and circRNAs, establish a complex network of reciprocally interacting molecules whose final goal is the regulation of mRNA expression. Likewise, these interactions are stochastically regulated by ncRNA abundance. Thus, while protein sequence is deterministically dictated by the DNA/RNA/protein axis, protein abundance and activity are regulated by two stochastic processes acting, respectively, before and after the biosynthesis of the protein axis. Consequently, the worlds of glycosylation and ncRNA are closely interconnected and mutually interacting. In this paper, we will extensively review the many faces of the ncRNA-glycosylation interplay in cancer and other physio-pathological conditions.

The regulatory roles of circular RNAs via autophagy in ischemic stroke

Ischemic stroke (IS) is a severe disease with a high disability, recurrence, and mortality rates. Autophagy, a highly conserved process that degrades damaged or aging organelles and excess cellular components to maintain homeostasis, is activated during IS. It influences the blood–brain barrier integrity and regulates apoptosis. Circular RNAs (circRNAs) are novel non-coding RNAs involved in IS-induced autophagy and participate in various pathological processes following IS. In addition, they play a role in autophagy regulation. This review summarizes current evidence on the roles of autophagy and circRNA in IS and the potential mechanisms by which circRNAs regulate autophagy to influence IS injury. This review serves as a basis for the clinical application of circRNAs as novel biomarkers and therapeutic targets in the future.

Circular RNA-regulated autophagy is involved in cancer progression

Circular RNAs (circRNAs) are a sort of long, non-coding RNA molecules with a covalently closed continuous ring structure without 5'-3' polarity and poly-A tail. The modulative role of circRNAs in malignant diseases has been elucidated by many studies in recent years via bioinformatics and high-throughput sequencing technologies. Generally, circRNA affects the proliferative, invasive, and migrative capacity of malignant cells via various mechanisms, exhibiting great potential as novel biomarkers in the diagnoses or treatments of malignancies. Meanwhile, autophagy preserves cellular homeostasis, serving as a vital molecular process in tumor progression. Mounting studies have demonstrated that autophagy can not only contribute to cancer cell survival but can also induce autophagic cell death in specific conditions. A growing number of research studies have indicated that there existed abundant associations between circRNAs and autophagy. Herein, we systemically reviewed and discussed recent studies on this topic in different malignancies and concluded that the circRNA–autophagy axis played crucial roles in the proliferation, metastasis, invasion, and drug or radiation resistance of different tumor cells.

The Tumor Suppressor Roles and Mechanisms of MiR-491 in Human Cancers

MicroRNAs (miRNAs) are short non-coding RNAs that bind to the 3' untranslated region (3'' UTR) of target mRNAs to control gene expression post-transcriptionally. Recent indications have highlighted their important roles in a variety of pathophysiological conditions as well as human malignancies. Dysregulated miRNAs act as tumor suppressor genes or oncogenes in a variety of cancers. MiR-491 has been shown to have a major effect on tumorigenesis in multiple malignancies through binding to specific genes and signaling cascades, thereby preventing cancer progression. This review provides an overview of miR-491 expression in regulatory mechanisms and biological procedures of tumor cells, as well as the prospective possible treatment effects of various types of human cancers.

Glycosyltransferases in Cancer: Prognostic Biomarkers of Survival in Patient Cohorts and Impact on Malignancy in Experimental Models

Background: Glycosylation changes are a main feature of cancer. Some carbohydrate epitopes and expression levels of glycosyltransferases have been used or proposed as prognostic markers, while many experimental works have investigated the role of glycosyltransferases in malignancy. Using the transcriptomic data of the 21 TCGA cohorts, we correlated the expression level of 114 glycosyltransferases with the overall survival of patients. Methods: Using the Oncolnc website, we determined the Kaplan−Meier survival curves for the patients falling in the 15% upper or lower percentile of mRNA expression of each glycosyltransferase. Results: Seventeen glycosyltransferases involved in initial steps of N- or O-glycosylation and of glycolipid biosynthesis, in chain extension and sialylation were unequivocally associated with bad prognosis in a majority of cohorts. Four glycosyltransferases were associated with good prognosis. Other glycosyltransferases displayed an extremely high predictive value in only one or a few cohorts. The top were GALNT3, ALG6 and B3GNT7, which displayed a p < 1 × 10−9 in the low-grade glioma (LGG) cohort. Comparison with published experimental data points to ALG3, GALNT2, B4GALNT1, POFUT1, B4GALT5, B3GNT5 and ST3GAL2 as the most consistently malignancy-associated enzymes. Conclusions: We identified several cancer-associated glycosyltransferases as potential prognostic markers and therapeutic targets.