The bioinformatics toolbox for circRNA discovery and analysis

METTL3 mediates m6A modification of hsa_circ_0072380 to regulate the progression of gestational diabetes mellitus

BACKGROUND

m6A modification plays a vital role in gestational diabetes mellitus (GDM) progression. However, the role of METTL3 and differential m6A-modified circRNAs in GDMremainsto be investigated.

METHODS

Placental tissue samples from GDM patients and normal controls (NC) were collected to measure changes in m6A modification levels. MeRIP-seq on placental tissue was performed to detect differential m6A-modified circRNAs.High glucose (HG)-treated JEG3 cells were used to establish the GDM cell model. Differentially expressed circRNAs levels in GDM and NC groups were measured by qRT-PCR. We knocked down METTL3 to study its function. Additionally, we conducted functional recovery experiments. Dot blot assay was utilized to assess changes in m6A levels. MeRIP-qPCR was performed to evaluate the effect of knocking down METTL3 on m6A modification of hsa_circ_0072380 in JEG3 cells.

RESULTS

Compared with the NC group, the GDM group exhibited increased levels of m6A modification and METTL3 expression. Differences in m6A modification of circRNAs exist between the GDM and NC groups. Hsa_circ_0000994, hsa_circ_0058733, and hsa_circ_0072380 were significantly down-regulated in the GDM group while hsa_circ_0036376, hsa_circ_0000471, and hsa_circ_0001173 showed no significant differences between two groups. HG treatment promoted METTL3 expression and m6A level of JEG3 cells, and inhibited cell proliferation, migration, and invasion abilities. Knocking down METTL3 reversed these effects. After HG treatment, hsa_circ_0072380 was significantly down-regulated. Knocking down METTL3 led to up-regulation of hsa_circ_0072380, while knocking down hsa_circ_0072380 restored the function of SiMETTL3. Additionally, knocking down METTL3 significantly reduced the m6A modification of hsa_circ_0072380.

CONCLUSION

METTL3 mediated m6A modification of hsa_circ_0072380 to regulate GDM progression.

Therapeutic importance and diagnostic function of circRNAs in urological cancers: from metastasis to drug resistance

Circular RNAs (circRNAs) are a member of non-coding RNAs with no ability in encoding proteins and their aberrant dysregulation is observed in cancers. Their closed-loop structure has increased their stability, and they are reliable biomarkers for cancer diagnosis. Urological cancers have been responsible for high mortality and morbidity worldwide, and developing new strategies in their treatment, especially based on gene therapy, is of importance since these malignant diseases do not respond to conventional therapies. In the current review, three important aims are followed. At the first step, the role of circRNAs in increasing or decreasing the progression of urological cancers is discussed, and the double-edged sword function of them is also highlighted. At the second step, the interaction of circRNAs with molecular targets responsible for urological cancer progression is discussed, and their impact on molecular processes such as apoptosis, autophagy, EMT, and MMPs is highlighted. Finally, the use of circRNAs as biomarkers in the diagnosis and prognosis of urological cancer patients is discussed to translate current findings in the clinic for better treatment of patients. Furthermore, since circRNAs can be transferred to tumor via exosomes and the interactions in tumor microenvironment provided by exosomes such as between macrophages and cancer cells is of importance in cancer progression, a separate section has been devoted to the role of exosomal circRNAs in urological tumors.

Circular RNA circPHF16 enhances IL-17A expression and secretion by sequestering miR-378a-3p to activate the IL6ST axis in Graves' disease

Interleukin-17A (IL-17A) plays a pivotal role in the pathogenesis of Graves' disease (GD), an autoimmune disorder affecting thyroid function, but the detailed regulatory mechanisms remain elusive. Circular RNAs (circRNAs) have emerged as key regulators of IL-17A expression and secretion in autoimmune diseases, yet their specific role in GD, especially within CD4 + T lymphocytes, are not well understood. In this study, a circRNA, circPHF16 (hsa_circ_0090364) was found to be highly expressed in the peripheral blood mononuclear cells and serum of GD patients. In vitro experiments in Jurkat T cells revealed that silencing of circPHF16 suppressed IL-17A expression and secretion, while overexpression of circPHF16 had the opposite effect. Furthermore, bioinformatics analysis demonstrated a circPHF16/miR-378a-3p/IL6ST pathway, in which circPHF16 regulates IL6ST expression, which, in turn, influences IL-17A expression and secretion by interacting with miR-378a-3p. In vivo studies in a mouse model of GD showed similar trends in molecular expression levels, consistent with competitive endogenous RNA interactions. Together the results of the study identify circPHF16 as a potential target in the development of new strategies for GD diagnosis and treatment, and thus, offer a theoretical foundation for clinical therapeutic approaches in GD.

Therapeutic SHPRH-146aa encoded by circ-SHPRH dynamically upregulates P21 to inhibit CDKs in neuroblastoma

Recent research has underscored the significance of circular RNAs (circRNAs) in various cancers, including neuroblastoma (NB). Specifically, circ-SHPRH, a unique circRNA, has been revealed to inhibit tumor growth by sequestering miRNAs or producing the SHPRH-146aa protein. To explore circ-SHPRH's involvement in NB and its potential application in gene therapy, this study examined circ-SHPRH expression in 94 NB tissues and cell lines (SK-N-BE(2), SH-SY5Y) using real-time PCR and fluorescence in situ hybridization (FISH). Functional assays encompassing both overexpression and knockdown experiments in NB cell lines, as well as in vivo investigations, were conducted. RNA-seq analysis revealed a correlation between circ-SHPRH and the pathway of P21 (CDKN1A), a pivotal cell cycle regulator. Validation through PCR and other techniques confirmed that circ-SHPRH upregulated P21 expression. Furthermore, the regulatory role of circ-SHPRH in the P21-CDK pathway was corroborated through SHPRH-146aa expression analysis. Notably, adenovirus-mediated circ-SHPRH overexpression effectively curbed NB tumor growth in NSG mice, while combining circ-SHPRH with everolimus exhibited potential for NB treatment. This study elucidates the remarkable significance of circ-SHPRH in NB and its prospective utility in gene therapy, thereby paving the way for innovative therapeutic approaches.

CircXPO6 promotes breast cancer progression through competitively inhibiting the ubiquitination degradation of c-Myc

The number of breast cancer (BC) patients is increasing year by year, which is severely endangering to human life and health. c-Myc is a transcription factor, studies have shown that it is a very significant factor in tumor progression, but how it is regulated in BC is still not well understood. Here, we used the RIP microarray sequencing to confirm circXPO6, which had a high affinity with c-Myc and highly expressed in triple-negative breast cancer (TNBC) tissues and cells. CircXPO6 overexpression promoted tumor growth in vivo and in vitro. Furthermore, circXPO6 largely promoted the expression of genes related to glucose metabolism, such as GLUT1, HK2, and MCT4 in TNBC cells. Finally, high levels of circXPO6 expression were found to be closely associated with malignant pathological factors, such as tumor size, lymph node metastasis, TNM staging, and histopathological grading of TNBC. Mechanistically, circXPO6 interacted with c-Myc to prevent speckle-type POZ-mediated c-Myc ubiquitination and degradation, thus promoting TNBC progression. Through the regulation of c-Myc-mediated signal transduction, circXPO6 plays a key role in TNBC progresses. This discovery can provide new ideas for TNBC molecular targeted therapy.

Levosimendan mediates the BMP/Smad axis through upregulation of circUSP34-targeted miR-1298 to alleviate pulmonary hypertension

BACKGROUND

Pulmonary hypertension (PH) is a long-term disease that impacts approximately 1% of the world's population. Currently, levosimendan (Lev) is proposed for PH treatment. However, the mechanism of Lev in the treatment of PH is unknown.

METHODS

We used hypoxia-induced pulmonary artery smooth muscle cells (PASMCs) to establish a PH cell model. A number of cell biology methods were performed to assay alterations in cell proliferation, migration and apoptosis after Lev treatment. qRT-PCR and WB were performed to test the levels of circUSP34 and miR-1298, and BMP/Smad protein respectively. In addition, the regulatory relationship between circUSP34 or BMPR2 with miR-1298 was verified through the use of double luciferase as well as RIP assay. In addition, we explored the regulatory effect of Lev on the circUSP34/miR-1298/BMP/Smad axis using a rat PH model.

RESULTS

Our results demonstrate that Lev inhibited PASMCs cell proliferation, migration and promoted apoptosis exposed to hypoxia. In hypoxia-treated PASMCs, circUSP34 expression got downregulated while miR-1298 upregulated, whereas the addition with Lev resulted in upregulation of circUSP34 expression and downregulation of miR-1298 expression, indicating that circUSP34 can target and regulate miR-1298. In addition, miR-1298 targets and regulates the expression of BMPR2. In a rat PH model induced by hypoxia combined with SU5416, Lev upregulated circUSP34 targeting miR-1298-mediated BMP/Smad axis to alleviate the PH phenotype.

CONCLUSION

We have shown that Lev can be used as a therapeutic drug for PH patients, which works through the circUSP34/miR-1298/BMP/Smad axis to alleviate PH symptoms.

An updated resource for the detection of protein-coding circRNA with CircProPlus

Protein-encoding circular RNAs (circRNAs) are newly identified RNA molecules characterized by intense interaction with translating ribosome. Emerging evidence has implicated physiological and pathological significance of these non-canonical RNAs, yet a large body of them remains unidentified. Due to limited tools at hand, we developed CircProPlus, an automated computational pipeline for de novo detection of translated circRNAs. In comparison to previously established CircPro, CircProPlus adjusts the overall workflow and integrates more robust implements for achieving easier accessibility, higher flexibility and productivity. In present study, we tested the performance of CircProPlus when using different circRNA-detecting implements (i.e., CIRI2, CirComPara2) in the evaluation of coding ability of circRNAs. Results showed that CirComPara2, a state-of-the-art algorithm, consistently outperformed CIRI2 when coupled with CircProPlus in testing real data collected from different RNA libraries and species, which highlighted its potency in data mining of circRNAs with protein-coding potential.

CircRNA hsa_circ_0003528/miR-215 is considered a potential target for predictive prognosis and therapy for triple-negative breast cancer

BACKGROUND

Within the subtypes of breast cancer pathologies, triple-negative breast cancer (TNBC) exhibits the highest degree of malignancy and unfavorable outcome, which has great significance in exploring the molecular mechanisms underlying TNBC. This study especially investigated the expression and function of hsa_circ_0003528 in TNBC.

METHODS

The expression changes of hsa_circ_0003528 were identified from the GEO database (GSE101123) and validated by RT-qPCR. The clinical significance of hsa_circ_0003528 was evaluated using χ2 tests and Kaplan-Meier curve analysis. Bioinformatic analysis and dual-luciferase reporter assay were used to identify the potential downstream miRNA of hsa_circ_0003528. The cellular experiments were conducted to evaluate the impact of hsa_circ_0003528 or/and miR-215 on TNBC cells.

RESULTS

The hsa_circ_0003528 was selected from the circRNA profile in breast cancer obtained from the GSE101123 dataset. hsa_circ_0003528 expression levels were increased in breast cancer tissues, especially in TNBC tissues. The elevated expression of hsa_circ_0003528 was negatively associated with TNBC patients' overall survival. Silencing of hsa_circ_0003528 hindered the proliferative potential, migration abilities, and invasive capacities of TNBC cells, while downregulation of miR-215 partially diminished the effects of si-hsa_circ_0003528 on TNBC cells.

CONCLUSION

hsa_circ_0003528 is upregulated in TNBC and can facilitate aggressive cellular behaviors by regulating miR-215 expression, hinting at its potential as a biomarker and therapeutic target in the treatment of TNBC.

Circular RNA ACVR2A promotes the progression of hepatocellular carcinoma through mir-511-5p targeting PI3K-Akt signaling pathway

Circular RNA (circRNA) is thought to mediate the occurrence and development of human cancer and usually acts as a tiny RNA (miRNA) sponge to regulate downstream gene expression. However, it is not clear whether and how circACVR2A (hsa_circ_0001073) is involved in the progression of HCC. The purpose of this study is to clarify the potential role and molecular mechanism of circACVR2A in regulating the progression of hepatocellular carcinoma cells (HCC). The abundance of related proteins in circACVR2A, microRNA (miR511-5p) and PI3K-Akt signaling pathway was determined by quantitative reverse transcriptase polymerase chain reaction (RT-PCR) or Western blotting. Cell viability, invasion and apoptosis were analyzed by CCK-8, Transwell analysis and Tunel staining, respectively. The interaction between circACVR2A and microRNA was evaluated by double luciferase reporter gene assay. The results showed that circACVR2A was highly expressed in hepatocellular carcinoma cell lines. Our in vivo and in vitro data showed that circACVR2A promoted the proliferation, migration and invasion of HCC. In terms of mechanism, we found that circACVR2A can directly interact with miR511-5p and act as a miRNA sponge to regulate the expression of related proteins in PI3K-Akt signaling pathway.In HCC, circACVR2A can mediate miR-511-5p/mRNA network to activate PI3K signal pathway. This shows that the molecular regulatory network with circACVR2A as the core is a new potential target for diagnosis and treatment of hepatocellular carcinoma.

CD105+CAF-derived exosomes CircAMPK1 promotes pancreatic cancer progression by activating autophagy

Previous studies have shown that the heterogeneity of tumor-associated fibroblasts (CAFs) in the tumor microenvironment may play a critical role in tumorigenesis; however, the biological function of CAFs in pancreatic cancer is still controversial. In this study, we found that CD105-positive (CD105+) CAF-derived exosomes significantly promoted the proliferative and invasive metastatic abilities of pancreatic cancer cells. Furthermore, RNA-seq and qRT‒PCR experiments revealed circAMPK1 as a key molecule in exosomes from CD105+ CAFs that mediates the malignant progression of pancreatic cancer. Furthermore, we demonstrated that circAMPK1 encodes a novel protein (AMPK1-360aa) in pancreatic cancer cells. This protein competes with AMPK1 to bind to the ubiquitination ligase NEDD4, which inhibits AMPK1 protein degradation and ubiquitination and thereby increases AMPK1 levels. Finally, we demonstrated that AMPK1-360aa induces cellular autophagy via NEDD4/AMPK1 to promote the proliferation and invasion of pancreatic cancer cells. In summary, circAMPK1 in CD105+ CAF-derived exosomes may mediate pancreatic cancer cell proliferation and invasive metastasis by inducing autophagy in target cells. Moreover, circAMPK1 may competitively bind to ubiquitinating enzymes through the encoded protein AMPK1-360aa, which in turn inhibits the ubiquitination-mediated degradation of AMPK1 and contributes to the upregulation of AMPK1 expression, thus inducing cellular autophagy to mediate the malignant progression of pancreatic cancer.

Glioma stem cells remodel immunotolerant microenvironment in GBM and are associated with therapeutic advancements

Glioma is the most common primary tumor of the central nervous system (CNS). Glioblastoma (GBM) is incurable with current treatment strategies. Additionally, the treatment of recurrent GBM (rGBM) is often referred to as terminal treatment, necessitating hospice-level care and management. The presence of the blood-brain barrier (BBB) gives GBM a more challenging or "cold" tumor microenvironment (TME) than that of other cancers and gloma stem cells (GSCs) play an important role in the TME remodeling, occurrence, development and recurrence of giloma. In this review, our primary focus will be on discussing the following topics: niche-associated GSCs and macrophages, new theories regarding GSC and TME involving pyroptosis and ferroptosis in GBM, metabolic adaptations of GSCs, the influence of the cold environment in GBM on immunotherapy, potential strategies to transform the cold GBM TME into a hot one, and the advancement of GBM immunotherapy and GBM models.

Transcriptome Analysis of Hypothalamic-Pituitary-Ovarian Axis Reveals circRNAs Related to Egg Production of Bian Chicken

The hypothalamic-pituitary-ovarian (HPO) axis plays a pivotal role in the regulation of egg production in chickens. In addition to the traditional understanding of the HPO axis, emerging research highlights the significant role of circRNAs in modulating the functions of this axis. In the study, we collected hypothalamus, pituitary, and ovarian tissues from low-yielding and high-yielding Bian chickens for transcriptome sequencing. We identified 339, 339, and 287 differentially expressed (DE) circRNAs with p_value < 0.05 and |log2 (fold change)| ≥ 1 in hypothalamus, pituitary, and ovarian tissues. The Gene Ontology (GO) enrichment analysis for the source genes of DE circRNAs has yielded multiple biological process (BP) entries related to cell development, the nervous system, and proteins, including cellular component morphogenesis, cell morphogenesis, nervous system development, neurogenesis, protein modification process, and protein metabolic process. In the top 30 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, we observed the enrichment of the GnRH signaling pathway in both the hypothalamus and the pituitary, solely identified the GnRH secretion pathway in the pituitary, and discovered the pathway of oocyte meiosis in the ovary. Furthermore, given that circRNA primarily functions through the ceRNA mechanism, we constructed ceRNA regulatory networks with DE circRNAs originating from the GnRH signaling pathway, GnRH secretion, ovarian steroidogenesis, steroid hormone biosynthesis, and the estrogen signaling pathway. Finally, several important ceRNA regulatory networks related to reproduction were discovered, such as novel_circ_003662-gga-let-7b/miR-148a-3p/miR-146a-5p/miR-146b-5p and novel_circ_003538-gga-miR-7464-3p-SLC19A1. This study will contribute to advancements in understanding the involvement of circRNAs in the HPO axis, potentially leading to innovations in improving egg production and poultry health.

Advances in noncoding RNA in children allergic rhinitis

BACKGROUND

A chronic condition that significantly reduces a child's quality of life is allergic rhinitis (AR). The environment and allergens that the body is regularly exposed to can cause inflammatory and immunological reactions, which can change the expression of certain genes Epigenetic changes are closely linked to the onset and severity of allergy disorders according to mounting amounts of data. Noncoding RNAs (ncRNAs) are a group of RNA molecules that cannot be converted into polypeptides. The three main categories of ncRNAs include microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs). NcRNAs play a crucial role in controlling gene expression and contribute to the development of numerous human diseases.

METHODS

Articles are selected based on Pubmed's literature review and the author's personal knowledge. The largest and highest quality studies were included. The search selection is not standardized.

RESULTS

Recent findings indicate that various categories of ncRNAs play distinct yet interconnected roles and actively contribute to intricate gene regulatory networks.

CONCLUSION

This article demonstrates the significance and progress of ncRNAs in children's AR. The database covers three key areas: miRNAs, lncRNAs, and circRNAs. Additionally, potential avenues for future research to facilitate the practical application of ncRNAs as therapeutic targets and biomarkers will be explore.

Non-coding RNAs Function in Periodontal Ligament Stem Cells

Non-coding RNA has many types which has rich functions and plays an important role in the study of basic molecular mechanisms. Many non-coding RNA have important implications for pluripotent stem cells and embryonic stem cells. It has been found to affect the self-renewal and osteogenesis of many types of stem cells. They have also been found to regulate stem cell proliferation and induct bone differentiation. Periodontal ligament stem cells are essential for the regeneration of periodontal tissue. In recent years, in the field of stomatology, studies have found that many non-coding RNA also have significant regulatory effects on the proliferation and differentiation of periodontal stem cells and may become potential therapeutic targets for many common periodontal diseases such as periodontitis, bone/tooth/soft tissue loss and orthodontic treatment. Therefore, we summarized the current research status of non-coding RNA in the field of molecular mechanism of periodontal ligament stem cells and prospected its future progress.

Bibliometric Analysis of Global Research on Circular RNA: Current Status and Future Directions

Circular RNAs (circRNAs) have gained significant attention in recent years. This bibliometric analysis aimed to provide insights into the current state and future trends of global circRNA research. The scientific output on circRNAs from 2010 to 2022 was retrieved from the Web of Science Core Collection with circRNA-related terms as the subjects. Key bibliometric indicators were calculated and evaluated using CiteSpace. A total of 7385 studies on circRNAs were identified. The output and citation number have increased rapidly after 2015. China, the USA, and Germany were top three publishing countries. Currently, circCDR1as, circHIPK3, circPVT1, circSHPRH, and circZNF609 are the most studied circRNAs; and all are related to cancer. The theme of research have shifted from transcript, exon circularization and miRNA sponge topics to the transcriptome, tumor suppressor, and biomarkers, indicating that research interests have evolved from basic to applied research. CircRNAs will continue to be a highly active research area in the near future. From the current understanding of circRNA characterization and regulatory mechanisms as miRNA sponges in cancer, future directions may examine potential diagnostic and therapeutic roles of circRNAs in cancers or the function and mechanism of circRNAs in other diseases.

Circular RNA NFIX Functions as an Oncogene in Non-Small Cell Lung Cancer by Modulating the miR-214-3p/TRIAP1 Axis

BACKGROUND

circRNA NFIX has been shown to exist as an oncogene in glioma. But its expression and role in NSCLC (non-small cell lung cancer) are still unclear. This research aimed to discover the expression and function of circRNA NFIX in NSCLC.

METHODS

In this research, qRT-PCR was utilized to investigate the expression levels of circRNA NFIX, miRNA-214-3p, and TRIAP1 in NSCLC tissues and cell lines. The binding sites between circRNA NFIX/TRIAP1 and miRNA-214-3p were predicted using the Starbase. These interactions were further validated using a double luciferase reporter assay. Cell proliferation and apoptosis were assessed through MTT and flow cytometry, respectively. The expression of apoptosis-related proteins was measured by western blot assay.

RESULTS

miRNA-214-3p could link with circRNA NFIX. circRNA NFIX was upregulated, while miRNA-214-3p was downregulated in NSCLC cell lines and clinical samples. Besides, suppression of circRNA NFIX repressed cell proliferation and induced apoptosis in NSCLC cells by upregulating miRNA-214-3p expression. Besides, the data indicated that TRIAP1 was a target of miRNA-214-3p, and it was negatively regulated by miRNA-214-3p in NSCLC cells. The excessive expression of miRNA-214-3p suppressed NSCLC cell proliferation and increased apoptosis. In addition, overexpression of TRIAP1 significantly reversed the effects on NSCLC cells caused by miRNA-214-3p mimic.

CONCLUSION

circRNA NFIX silencing repressed the proliferation of NSCLC cells and induced cell apoptosis by regulating the miR-214-3p/TRIAP1 axis, which was a potential diagnostic and therapeutic target for NSCLC.

circADAMTS6 via stabilizing CAMK2A is involved in smoking-induced emphysema through driving M2 macrophage polarization

Cigarette smoke (CS), an indoor environmental pollutant, is a prominent risk factor for emphysema, which is a pathological feature of chronic obstructive pulmonary disease (COPD). Emerging function of circRNAs in immune responses and disease progression shed new light to explore the pathogenesis of emphysema. In this research, we demonstrated, by single-cell RNA sequencing (scRNAseq), that the ratio of M2 macrophages were increased in lung tissues of humans and mice with smoking-related emphysema. Further, our data showed that circADAMTS6 was associated with cigarette smoke extract (CSE)-induced M2 macrophage polarization. Mechanistically, in macrophages, circADAMTS6 stabilized CAMK2A mRNA via forming a circADAMTS6/IGF2BP2/CAMK2A RNA-protein ternary complex to activate CREB, which drives M2 macrophage polarization and leads to emphysema. In addition, in macrophages of mouse lung tissues, downregulation of circADAMTS6 reversed M2 macrophage polarization, the proteinase/anti-proteinase imbalance, and the elastin degradation, which protecting against CS-induced emphysema. Moreover, for macrophages and in a model with co-cultured lung organoids, the target of circADAMTS6 restored the growth of lung organoids compared to CSE-treated macrophages. Our results also demonstrated that, for smokers and COPD smokers, elevation of circADAMTS6 negatively correlated with lung function. Overall, this study reveals a novel mechanism for circADAMTS6-driven M2 macrophage polarization in smoking-related emphysema and postulates that circADAMTS6 could serve as a diagnostic and therapeutic marker for smoking-related emphysema.

Circular RNAs and the JAK/STAT pathway: New frontiers in cancer therapeutics

Circular RNAs, known as circRNAs, have drawn more attention to cancer biology in the last few years. Novel functions of circRNAs in cancer therapy open promising prospects for personalized medicine. This review focuses on the molecular properties and potential of circRNAs as biomarkers or therapeutic targets in cancer treatment. Unique properties of circular RNAs associated with a circular form provide stability and resilience to RNA exonuclease degradation. Circular RNAs' most important characteristic is that they are involved in the JAK/STAT pathway associated with oncogenesis. Notably, their deregulation has been reported in multiple carcinomas due to involvement in JAK/STAT signaling cascade modulation. Increased knowledge about circRNAs' interaction with the JAK/STAT pathway leads to the emergence of new possibilities for targeted cancer therapy. In addition, since circRNAs demonstrate tissue-relatedness of expression, they may be a reliable biomarker for predicting and diagnosing cancer. With the development of new technologies for targeting circRNAs, novel therapeutics can be produced that offer more personalized cancer treatment options based on the nature of the patient. The present review explores the exciting prospects of circRNAs for transforming cancer treatment into personalized medicine. It describes the current understanding of circRNA biology, its relationship to tumorigenesis, and possible targeting methods.

Comprehensive analysis of circRNA-miRNA-mRNA network related to angiogenesis in recurrent implantation failure

BACKGROUND

Abnormal endometrial blood flow causes a decrease in endometrial receptivity and is considered a relatively independent risk factor for recurrent implantation failure (RIF). This study aimed to explore the potentially functional circRNA-miRNA-mRNA network in RIF, and further explore its mechanism.

METHODS

Datasets were downloaded from the GEO database to identify differentially expressed circRNAs, miRNAs and mRNAs. The circRNA-miRNA-mRNA and PPI networks were constructed using Cytoscape 3.6.0 and the STRING database, the hub genes were identified with the cytoHubba plug-in, and a circRNA-miRNA-hub mRNA regulatory sub-network was constructed. Then, GO and KEGG pathway enrichment analyses of the hub genes were performed to comprehensively analyze the mechanism of hub mRNAs in RIF. Due to the results of circRNAs-miRNAs-hub mRNAs regulatory network, we verified the expression of circRNA_0001721, circRNA_0000714, miR-17-5p, miR-29b-3p, HIF1A and VEGFA in the RIF mouse model by qRT‒PCR and western blotting.

RESULTS

We initially identified 175 DEmRNAs, 48 DEmiRNAs and 56 DEcircRNAs in RIF associated with angiogenesis and constructed a circRNA-miRNA‒mRNA network and PPI network. We further identified six hub genes in the acquired network. Based on these genes, functional enrichment analysis revealed that the HIF-1 signaling pathway plays a vital role in endometrial angiogenesis in RIF. In addition, the interaction networks of circRNA_0001721/miR-17-5p/HIF1A and the circRNA_0000714/miR-29b-3p/VEGFA axis were predicted. In the RIF mouse model, circRNA_0001721, circRNA_0000714, HIF1A and VEGFA were down-regulated, whereas miR-17-5p and miR-29b-3p were up-regulated according to qRT‒PCR and western blotting.

CONCLUSION

This study revealed that the HIF-1 signaling pathway plays a vital role in endometrial angiogenesis in RIF. The circRNA_0001721/miR-17-5p/HIF1A and circRNA_0000714/miR-29b-3p/VEGFA axes might play a role in the pathogenesis of endometrial angiogenesis in RIF.

Advances in CircRNAs in the Past Decade: Review of CircRNAs Biogenesis, Regulatory Mechanisms, and Functions in Plants

Circular RNA (circRNA) is a type of non-coding RNA with multiple biological functions. Whole circRNA genomes in plants have been identified, and circRNAs have been demonstrated to be widely present and highly expressed in various plant tissues and organs. CircRNAs are highly stable and conserved in plants, and exhibit tissue specificity and developmental stage specificity. CircRNAs often interact with other biomolecules, such as miRNAs and proteins, thereby regulating gene expression, interfering with gene function, and affecting plant growth and development or response to environmental stress. CircRNAs are less studied in plants than in animals, and their regulatory mechanisms of biogenesis and molecular functions are not fully understood. A variety of circRNAs in plants are involved in regulating growth and development and responding to environmental stress. This review focuses on the biogenesis and regulatory mechanisms of circRNAs, as well as their biological functions during growth, development, and stress responses in plants, including a discussion of plant circRNA research prospects. Understanding the generation and regulatory mechanisms of circRNAs is a challenging but important topic in the field of circRNAs in plants, as it can provide insights into plant life activities and their response mechanisms to biotic or abiotic stresses as well as new strategies for plant molecular breeding and pest control.

circPTP4A2 knockdown suppresses NSCLC progression via regulating proliferation and activating anti-tumor immunity

BACKGROUND

With a considerable variety of cancer subtypes, Non-small cell lung cancer (NSCLC) poses a substantial threat to public health, affecting a large number of individuals and resulting in a high mortality rate. Circular RNA (circRNA) has been applied in various diseases, including cancers. This study aims to investigate the clinial significance and functional role of circPTP4A2 in NSCLC.

METHODS

The serum and tissue samples were collected for detecting circPTP4A2 expression in NSCLC using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Actinomycin D was used to treat NSCLC cells to detect circPTP4A2 stability. The CCK-8 and Transwell assays were utilized to assess the effects of circPTP4A2 in NSCLC cells. The ELISA assay and cytotoxicity analysis were used to detect the roles of circPTP4A2 in immune escape.

RESULTS

The serum and tissue circPTP4A2 expression was upregulated in NSCLC. The high circPTP4A2 had a relatively high value in differentiating NSCLC patients from healthy individuals. The proliferation, invasion, and immune escape were repressed by circPTP4A2 knockdown.

CONCLUSIONS

High circPTP4A2 has the potential to be a diagnostic biomarker in NSCLC. Silencing of circPTP4A2 receded the progression of NSCLC and enhanced antitumor immunity, which might provide potential targets and new ideas for improving the diagnosis and effect of immunotherapy in NSCLC patients.

Circular RNA Circ_0122396 Regulates Human Lens Epithelial Cell Progression by Regulating miR-23a-3p and MMP16 in Age-Related Cataract

BACKGROUND

CircRNA plays a regulatory role in multiple life processes. Circ_0122396 could participate in the regulation of age-related cataract (ARC) progression. However, the precise molecular mechanisms of circ_0122396 In ARC remain enigmatic.

METHODS

Circ_0122396, microRNA (miR)-23a-3p, and matrix metalloprotease (MMP)-16 (MMP16) expression levels were detected via quantitative real-time polymerase chain reaction. Western blot was used to detect the levels of MMP16 and apoptosis-related proteins. Cell counting kit-8 analysis and 5-ethynyl-2'-deoxyuridine assay were used to assess human lens epithelial cells (HLECs) proliferation. Flow cytometry was performed to determine cell apoptosis. Levels of malondialdehyde (MDA) and glutathione peroxidase (GSH-PX) were measured using commercial kits. Luciferase reporter assay, RNA immunoprecipitation (RIP) assay, and RNA pull-down assay were used to examine the interaction among circ_0122396, miR-23a-3p, and MMP16.

RESULTS

Circ_0122396 and MMP16 were down-regulated while miR-23a-3p was up-regulated in ARC. H2O2 constrained proliferation and GSH-PX level, promotes apoptosis and MDA level in HLECs, and overexpression of circ_0122396 attenuated these effects. miR-23a-3p was a direct target of circ_0122396, and MMP16 was a direct target of miR-23a-3p. The effect of circ_0122396 overexpression on H2O2-induced HLECs was reversed by miR-23a-3p, and MMP16 elevation overturned the impacts of miR-23a-3p in H2O2-induced HLECs.

CONCLUSIONS

Circ_0122396 may regulate the progression of ARC via the miR-23a-3p/MMP16 pathway in H2O2-stimulated HLECs, which may serve as a potentially valuable biomarker and novel therapeutic target for ARC.

Exposure of benzo[a]pyrene induces HCC exosome-circular RNA to activate lung fibroblasts and trigger organotropic metastasis

BACKGROUND

Benzo[a]pyrene (B[a]P), a carcinogen pollutant produced by combustion processes, is present in the western diet with grilled meats. Chronic exposure of B[a]P in hepatocellular carcinoma (HCC) cells promotes metastasis rather than primary proliferation, implying an unknown mechanism of B[a]P-induced malignancy. Given that exosomes carry bioactive molecules to distant sites, we investigated whether and how exosomes mediate cancer-stroma communications for a toxicologically associated microenvironment.

METHOD

Exosomes were isolated from B[a]P stimulated BEL7404 HCC cells (7404-100Bap Exo) at an environmental relevant dose (100 nmol/L). Lung pre-education animal model was prepared via injection of exosomes and cytokines. The inflammatory genes of educated lungs were evaluated using quantitative reverse transcription PCR array. HCC LM3 cells transfected with firefly luciferase were next injected to monitor tumor burdens and organotropic metastasis. Profile of B[a]P-exposed exosomes were determined by ceRNA microarray. Interactions between circular RNA (circRNA) and microRNAs (miRNAs) were detected using RNA pull-down in target lung fibroblasts. Fluorescence in situ hybridization and RNA immunoprecipitation assay was used to evaluate the "on-off" interaction of circRNA-miRNA pairs. We further developed an adeno-associated virus inhalation model to examine mRNA expression specific in lung, thereby exploring the mRNA targets of B[a]P induced circRNA-miRNA cascade.

RESULTS

Lung fibroblasts exert activation phenotypes, including focal adhesion and motility were altered by 7404-100Bap Exo. In the exosome-educated in vivo model, fibrosis factors and pro-inflammatory molecules of are up-regulated when injected with exosomes. Compared to non-exposed 7404 cells, circ_0011496 was up-regulated following B[a]P treatment and was mainly packaged into 7404-100Bap Exo. Exosomal circ_0011496 were delivered and competitively bound to miR-486-5p in recipient fibroblasts. The down-regulation of miR-486-5p converted fibroblast to cancer-associated fibroblast via regulating the downstream of Twinfilin-1 (TWF1) and matrix metalloproteinase-9 (MMP9) cascade. Additionally, increased TWF1, specifically in exosomal circ_0011496 educated lungs, could promote cancer-stroma crosstalk via activating vascular endothelial growth factor (VEGF). These modulated fibroblasts promoted endothelial cells angiogenesis and recruited primary HCC cells invasion, as a consequence of a pre-metastatic niche formation.

CONCLUSION

We demonstrated that B[a]P-induced tumor exosomes can deliver circ_0011496 to activate miR-486-5p/TWF1/MMP9 cascade in the lung fibroblasts, generating a feedback loop that promoted HCC metastasis.

CircVDAC3 sequesters microRNA-592 and elevates EIF4E3 expression to inhibit the progression of gastric cancer

BACKGROUND

Accumulating evidence has shown that circular RNAs (circRNAs) are involved in gastric cancer (GC) tumorigenesis. However, specific functional circRNAs in GC remain to be discovered, and their underlying mechanisms remain to be elucidated.

METHODS

CircRNAs that were differentially expressed between GC tissues and controls were analyzed using a circRNA microarray dataset. The expression of circVDAC3 in GC was determined using quantitative real-time PCR (qRT-PCR), and the structural features of circVDAC3 were validated. Cell function assays and animal experiments were conducted to explore the effects of circVDAC3 on GC. Finally, bioinformatics analysis, fluorescent in situ hybridization, and dual luciferase assays were used to analyze the downstream mechanisms of circVDAC3.

RESULTS

Our results showed that circVDAC3 was downregulated in GC and inhibited the proliferation and metastasis of GC cells. Mechanistically, circVDAC3 acts as a competing endogenous RNA (ceRNA) of miR-592 and deregulates the repression of EIF4E3 by miR-592. EIF4E3 is downregulated in GC and overexpression of miR-592 or knockdown of EIF4E3 in circVDAC3-overexpressing cells weakens the anticancer effect of circVDAC3.

CONCLUSION

Our study provides evidence that circVDAC3 affects the growth and metastasis of GC cells via the circVDAC3/miR-592/EIF4E3 axis. Our findings offer valuable insights into the mechanisms underlying GC tumorigenesis and suggest novel therapeutic strategies.

Exosomal circ50547 as a potential marker and promotor of gastric cancer progression via miR-217/HNF1B axis

BACKGROUND

Exosomes, one of small extracellular vesicles, play a vital role in cell to cell communication and contribute to the advancement of tumors through their cargo molecules. Exosomal circRNAs have emerged as significant players in various types of tumors. Thus, this study aimed to investigate how exosomal circRNAs are involved in the diagnosis and progression of gastric cancer (GC).

METHODS

Serum exosomes were characterized using transmission electron microscopy, nanoparticle tracking analysis and Western blot. CCK-8, colony formation and transwell assays were conducted to study the function of hsa_circ_0050547 (named as circ50547). qRT-PCR was used to quantify the expression of circ50547 in GC tissues and serum exosomes. Fluorescence in situ hybridization was applied to detect the cellular distribution of circ50547. Stemness and drug-resistance were detected by sphere formation, WB, flow cytometry and half-maximal inhibitory concentration analyses. Bioinformatic analyses, luciferase experiments, qRT-PCR and WB were used to investigate molecular mechanisms.

RESULTS

We discovered for the first time a new type of GC-derived exosomal circRNA, circ50547. We found that circ50547 is highly expressed in both GC tissues and serum exosomes. Interestingly, we observed that the diagnostic value of exosomal circ50547 is superior to that of serum circ50547. Circ50547 overexpression enhanced the proliferation, migration, invasion, stemness and drug resistance of GC cells, while knockdown of circ50547 showed the opposite effect. Mechanistically, circ50547 acted as a sponge for miR-217 to regulate the expression of HNF1B, which promoted gastric cancer progression.

CONCLUSION

Exosomal circ50547 may be a promising marker for the diagnosis and prognosis prediction of GC. These findings suggest that it plays an oncogenic role through miR-217/HNF1B signaling pathway in GC.

circIARS: a potential plasma biomarker for diagnosing non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is one of the most prevalent cancers in the world, and early diagnosis can effectively improve patient survival. Here, differentially expressed circIARS genes are screened from the sequencing results, and their molecular characteristics are examined by Sanger sequencing, RNase R assay, agarose gel electrophoresis (AGE), and fluorescence in situ hybridization (FISH). Real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) is performed to detect the expression level of circIARS. The diagnostic value of the signature is analyzed using a subject operating characteristic (ROC) curve. Moreover, plasma is collected from postsurgical, chemotherapy, and relapse patients to investigate the prognostic value of circIARS in NSCLC. The expression of circIARS is greater in both the plasma and tissues of NSCLC patients than in those of healthy individuals, and could be used to distinguish NSCLC patients from patients with benign pulmonary disease (BPD), small cell lung cancer (SCLC) patients, and healthy individuals. The expression level of circIARS relatively decreases after antitumor therapy, such as chemotherapy, and relatively increases after recurrence. ROC analysis reveals that circIARS has better detection efficiency than traditional markers. In addition, circIARS expression level is strongly correlated with several clinicopathological parameters. Finally, we tentatively predict the downstream miRNAs or RBP that might bind to circIARS. Plasma circIARS is significantly greater in NSCLC patients and has good stability and specificity as a diagnostic marker, which could aid in the adjuvant diagnosis and dynamic monitoring of NSCLC.

Hsa_circ_0010023 promotes the development of papillary thyroid carcinoma by sponging miR-1250-5p

BACKGROUND

Papillary thyroid cancer (PTC) is the most common thyroid tumor (TC). However, there is still a lack of effective indicators for PTC detection and prognosis. We intended to find a novel tumor marker for the progression of PTC.

METHODS

The expression of circRNAs was measured by quantitative real-time polymerase chain reaction (qRT-PCR). SiRNA transfection was used to knockdown the expression of hsa_circ_0010023 in K1 cells. Cell proliferation was evaluated using cell counting and CCK8. Cell apoptosis was analyzed using flow cytometry. Hsa_circ_0010023 downstream pathways were predicted with bio-informatics analysis. The miR-1250-5p and MAPK1 were measured by qRT-PCR. The interaction between miR-1250-5p and hsa_circ_0010023 was vertified by dual-luciferase reporter assay.

RESULTS

Among the four circRNAs screened, only hsa_circ_0010023 and hsa_circ_0128482 were highly expressed in PTC (P < 0.05). The expression of hsa_circ_0010023 was significantly correlated with lymph node metastasis and extrathyroid infiltration (P < 0.05). Compared with the control group, the cell proliferation of the si-circ-0010023 group was significantly inhibited (P < 0.05). Knockdown of hsa_circ_0010023 promotes apoptosis of K1 cells (P < 0.001). The expression of hsa_circ_0010023 was negatively correlated with miR-1250-5p and positively correlated with MAPK1. MiR-1250-5p overexpression significantly reduced the luciferase activity of wild type plasmid (hsa_circ_0010023 WT), but not that of mutant type plasmid (hsa_circ_0010023 MUT).

CONCLUSION

The expression level of hsa_circ_0010023 was positive related to the progression of PTC, and hsa_circ_0010023 may promote PTC through sponging miR-1250-5p. Hsa_circ_0010023 may be a potential bio-marker for the diagnosis of PTC.

Circ-USP9X accelerates deep vein thrombosis after fracture by acting as a miR-148b-3p sponge and upregulates SRC kinase signaling inhibitor 1

OBJECTIVES

This study aims to elucidate the role of circUSP9X (Circular RNA Ubiquitin Specific Peptidase 9 X-Linked) in the development of venous thrombosis in the lower extremities.

METHODS

An animal model of Deep Vein Thrombosis (DVT) and a hypoxic model of Human Umbilical Vein Endothelial Cells (HUVECs) treated with Cobalt (II) Chloride (CoCl2) were developed. The expression levels of circUSP9X, microRNA-148b-3p (miR-148b-3p), and SRC Kinase Signaling Inhibitor 1 (SRCIN1) were quantified using quantitative reverse transcription Polymerase Chain Reaction and Western blot analysis. Cell cytotoxicity, viability, apoptosis, and inflammation in HUVECs were assessed via Lactate Dehydrogenase (LDH) assay, MTT assay, flow cytometry, Enzyme-Linked Immunosorbent Assay, and Western blot, respectively. Hematoxylin and Eosin staining were employed for histopathological examination of the venous tissues in the animal model. The interaction between circUSP9X, miR-148b-3p, and SRCIN1 was further explored through dual-luciferase reporter assays and RNA Immunoprecipitation experiments.

RESULTS

The present findings reveal a significant upregulation of circUSP9X and SRCIN1 and a concurrent downregulation of miR-148b-3p in DVT cases. Knockdown of circUSP9X or overexpression of miR-148b-3p ameliorated CoCl2-induced apoptosis in HUVECs, reduced LDH release, enhanced cellular viability, and mitigated inflammation. Conversely, overexpression of circUSP9X intensified CoCl2's cytotoxic effects. The effects of manipulating circUSP9X expression were counteracted by the corresponding modulation of miR-148b-3p and SRCIN1 levels. Additionally, circUSP9X knockdown effectively inhibited the formation of DVT in the mouse model. A competitive binding mechanism of circUSP9X for miR-148b-3p, modulating SRCIN1 expression, was identified.

CONCLUSION

circUSP9X promotes the formation of DVT through the regulation of the miR-148b-3p/SRCIN1 axis.

Identification and characterization of Varicella Zoster Virus circular RNA in lytic infection

This study investigates the role of circular RNAs (circRNAs) in the context of Varicella-Zoster Virus (VZV) lytic infection. We employ two sequencing technologies, short-read sequencing and long-read sequencing, following RNase R treatment on VZV-infected neuroblastoma cells to identify and characterize both cellular and viral circRNAs. Our large scanning analysis identifies and subsequent experiments confirm 200 VZV circRNAs. Moreover, we discover numerous VZV latency-associated transcripts (VLTs)-like circRNAs (circVLTslytic), which contain multiple exons and different isoforms within the same back-splicing breakpoint. To understand the functional significance of these circVLTslytic, we utilize the Bacteria Artificial Chromosome system to disrupt the expression of viral circRNAs in genomic DNA location. We reveal that the sequence flanking circVLTs' 5' splice donor plays a pivotal role as a cis-acting element in the formation of circVLTslytic. The circVLTslytic is dispensable for VZV replication, but the mutation downstream of circVLTslytic exon 5 leads to increased acyclovir sensitivity in VZV infection models. This suggests that circVLTslytic may have a role in modulating the sensitivity to antiviral treatment. The findings shed new insight into the regulation of cellular and viral transcription during VZV lytic infection, emphasizing the intricate interplay between circRNAs and viral processes.

Circular RNA regulatory role in pathological cardiac remodelling

Cardiac remodelling involves structural, cellular and molecular alterations in the heart after injury, resulting in progressive loss of heart function and ultimately leading to heart failure. Circular RNAs (circRNAs) are a recently rediscovered class of non-coding RNAs that play regulatory roles in the pathogenesis of cardiovascular diseases, including heart failure. Thus, a more comprehensive understanding of the role of circRNAs in the processes governing cardiac remodelling may set the ground for the development of circRNA-based diagnostic and therapeutic strategies. In this review, the current knowledge about circRNA origin, conservation, characteristics and function is summarized. Bioinformatics and wet-lab methods used in circRNA research are discussed. The regulatory function of circRNAs in cardiac remodelling mechanisms such as cell death, cardiomyocyte hypertrophy, inflammation, fibrosis and metabolism is highlighted. Finally, key challenges and opportunities in circRNA research are discussed, and orientations for future work to address the pharmacological potential of circRNAs in heart failure are proposed.

Hsa_circ_0000069 Accelerates Cervical Cancer Progression by Sponging miR-1270 to Facilitate CPEB4 Expression

The critical importance of circular RNAs (circRNAs) in human cancers, including cervical cancer (CC), has been discovered in recent years. However, the function and mechanism of hsa_circ_0000069 (circ_0000069) in CC have been fully understood. The expression levels of circ_0000069, microRNAs (miR-1270, miR-1276 and miR-620) and cytoplasmic polyadenylation element binding protein 4 (CPEB4) mRNA were detected by quantitative real time polymerase chain reaction (qRT-PCR). Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, wound healing, transwell and tube formation assays were used to clarify the effects of circ_0000069 on the functional behaviors of CC cells. The binding relationships among miR-1270, circ_0000069 and CPEB4 were detected by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. A xenograft tumor model was established to explore the effect of circ_0000069 on tumor growth in vivo. Circ_0000069 was upregulated in CC clinical samples and cell lines, and its expression was associated with the clinical stage of CC patients. Circ_0000069 knockdown significantly decreased cell proliferation, invasion, migration, and tube formation and increased cell apoptosis in vitro. Moreover, miR-1270 was a direct target of circ_0000069, and CPEB4 was the downstream target of miR-1270. Knockdown of miR-1270 reversed the inhibitory effect of circ_0000069 knockdown on CC progression, and CPEB4 overexpression overturned the effect of miR-1270 on CC progression. In xenograft experiments, the oncogenic effect of circ_0000069 on tumor growth was verified. Altogether, circ_0000069 adsorbed miR-1270 to upregulate CPEB4 expression, thereby promoting the malignant phenotypes of CC cells. Circ_0000069 might be a potential target for treatment of CC.

To investigate the role and potential mechanism of has_circ_RBMS3 in bone metastasis of breast cancer based on bioinformatics

Circular RNAs (circRNAs) play a crucial regulatory role in malignant tumor metastasis. This study focused on the role of bone metastasis-related circRBMS3 in breast cancer. Two circRNA microarray datasets were obtained from the GEO database and overlapped bone metastasis-related circRNAs in breast cancer. CircRBMS3 expression was validated in bone metastasis tissues by RT-qPCR. Cellular CCK-8 assay and Transwell assays were performed to measure the effect of circRBMS3 in breast cancer cells. Bioinformatic analyses were performed to identify the binding miRNAs of circRBMS3 and downstream mRNAs. Online database STRING and Cytoscape software were used to analyze PPI interaction and conduct the ceRNA network. GEO database analysis showed that circRBMS3 was one of the upregulated circRNAs among all the metastatic cells. CircRBMS3 was increased in bone metastasis breast cancer tissues compared to non-bone metastasis tissues and associated with poor 3-year overall survival. CircRBMS3 knockdown repressed breast cancer cell proliferation, migration, and invasion, as well as bone resorption gene and osteoclast phenotype gene expression. CircRBMS3 was found to bind withmiR-654-3p. Subsequently, downstream mRNAs were predicted, and the circRBMS3 miR-654-3p-mRNA network was established. In conclusion, circRBMS3 expression was upregulated in bone metastasis breast cancer and might be a potential prognostic marker for patients. Silencing circRBMS3 restrained breast cancer cell proliferation, migration, and invasion, as well as associated with bone metastasis. The circRBMS3-miR-654-3p-mRNAs network elucidated potential mechanisms underlying bone metastasis in breast cancer.

A comprehensive evaluation of serum circCSPP1 as a novel diagnostic and prognostic biomarker for gastric cancer

PURPOSE

Gastric cancer (GC) has high incidence and mortality due to its low early screening efficiency. Circular RNAs (CircRNAs) are a new class of non-coding RNAs which is closely related to GC. Nevertheless, the clinical application value of circRNAs in GC are largely unknown. Therefore, we studied the role of a novel circRNA named circCSPP1 in patients with GC.

METHODS

CircRNA sequencing was performed to screen out the target molecule. Real-time fluorescent quantitative PCR (RT-qPCR) was utilized to detect the expression level of circCSPP1 in GC tissues, cells, and serum. Gel and Sanger sequencing were utilized to verify the ring structure of circCSPP1. RNase R enzyme digestion experiment and actinomycin D experiment were verifed the advantage of circCSPP1 as a diagnostic biomarker in patients with GC when that compared with linear RNA. The correlation between the expression level of serum circCSPP1 and clinicopathological data of GC patients was further analyzed. Receiver operating characteristic curve (ROC) and the area under ROC curve (AUC) were utilied to evaluate the diagnostic performance.

RESULTS

CircCSPP1 has a circular structure which with resistance to RNA exonuclease digestion and long half-life compared with linear RNA. In our study, circCSPP1 was first found up-regulated in patients with GC. Serum circCSPP1 level was decreased significantly after surgical resection whereas increased after recurrence. High expression of circCSPP1 was associated with poor survival rates. The expression level of circCSPP1 was significantly correlated to tumor size, T stage, lymph node metastasis, and TNM stage. The AUC of serum circCSPP1 was 0.834, with high sensitivity and specificity in discriminating patients with GC from healthy donors. More importantly, the combined diagnosis of circCSPP1, CEA, and CA19-9 achieved the superior AUC of 0.882, with the highest specificity.

CONCLUSION

Serum circCSPP1 may prove to be a potential non-invasive auxiliary diagnostic biomarker for patients with GC.

DEAD-Box Helicase 17 circRNA (circDDX17) Reduces Sorafenib Resistance and Tumorigenesis in Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the most common type of liver malignancy. Despite significant progress in HCC treatment, resistance to chemotherapy and tumor metastasis are the main reasons for the unsatisfactory prognosis of HCC. Circular RNAs (circRNAs) have been extensively documented to play a role in the development of various types of cancer.

AIMS

Here, we investigated the role of DEAD-box helicase 17 circRNA (circDDX17) in HCC and its underlying molecular mechanisms.

METHODS

Our research employed various techniques including reverse transcription-quantitative polymerase chain reaction (RT-qPCR), cell counting kit-8 (CCK-8), flow cytometry, dual luciferase reporter assay, RNA immunoprecipitation (RIP), and western blot analysis. Additionally, we conducted a tumor xenograft assay to investigate the in vivo function of circDDX17.

RESULTS

Firstly, the expression of circDDX17 was downregulated in HCC tissues and cells. Through functional experiments, it was observed that the overexpression of circDDX17 enhanced the sensitivity of sorafenib, promoted apoptosis, and inhibited the process of epithelial-mesenchymal transition (EMT) in vitro. Additionally, in vivo studies revealed that circDDX17 reduced tumor growth and increased sorafenib sensitivity. Mechanically, circDDX17 competitively combined miR-21-5p to suppress PTEN expression and activate the PI3K/AKT pathway. Furthermore, our rescue assays demonstrated that circDDX17 act as a tumor suppressor by blocking sorafenib resistance and tumorigenesis, while the inhibitory effect caused by circDDX17 upregulation was neutralized when miR-21-5p was overexpressed, PTEN was silenced, or the PI3K/AKT pathway was activated.

CONCLUSION

Our findings firstly confirmed that circDDX17 suppressed sorafenib resistance and HCC progression by regulating miR-21-5p/PTEN/PI3K/AKT pathway, which may provide novel biomarkers for the diagnosis, treatment and prognosis of HCC.

Decoding the neurotoxic effects of propofol: insights into the RARα-Snhg1-Bdnf regulatory cascade

The potential neurotoxic effects of propofol, an extensively utilized anesthetic, underline the urgency to comprehend its influence on neuronal health. Insights into the role of the retinoic acid receptor-α, small nucleolar RNA host gene 1, and brain-derived neurotrophic factor (RARα-Snhg1-Bdnf) network can offer significant advancements in minimizing these effects. The study targets the exploration of the RARα and Snhg1 regulatory network's influence on Bdnf expression in the realm of propofol-induced neurotoxicity. Harnessing the Gene Expression Omnibus (GEO) database and utilizing JASPAR and RNA-Protein Interaction Prediction (RPISeq) database for projections, the study embarks on an in-depth analysis employing both in vitro and in vivo models. The findings draw a clear link between propofol-induced neurotoxicity and the amplification of RAR signaling pathways, impacting hippocampal development and apoptosis and leading to increased RARα and Snhg1 and decreased Bdnf. Propofol is inferred to accentuate neurotoxicity by heightening RARα and Snhg1 interactions, culminating in Bdnf suppression.NEW & NOTEWORTHY This study aimed to decode propofol's neurotoxic effects on the regulatory cascade, provide insights into the RARα-Snhg1-Bdnf interaction, apply extensive validation techniques, provide a detailed analysis and exploration of propofol's neurotoxicity, and offer a comprehensive approach to understanding molecular interactions.

Characteristics of phosgene aspiration lung injury analyzed based on transcriptomics and proteomics

Background

Phosgene is a chemical material widely used worldwide. No effective method has been developed to reverse its pathological injuries. Some studies have shown that neuronal inflammation in lung tissue is involved, but the specific mechanism has not been reported.

Objective

To analyze the expression alterations of whole transcriptome gene sequencing bioinformatics and protein expression profile in lung tissue after phosgene aspiration lung injury (P-ALI) and find the main factors and pathways affecting the prognosis of P-ALI.

Methods

Rat models of P-ALI were made by phosgene. Rats were divided into a P-ALI group and a blank group. Hematoxylin-eosin (HE) staining and lung wet/dry ratio measurement were used to evaluate the lung injury. The levels of inflammatory factors were measured by ELISA. High-throughput sequencing was used to measure the expression profile of each gene. Protein expression profiles were determined by label-free relative quantification of the differential proteome.

Results

Lung injury such as the disordered structure of alveolar wall and inflammatory factors (IL-1β, IL-18, and IL-33) were significantly increased in the P-ALI group (p < 0.05). There were 225 differentially expressed lncRNAs, including 85 upregulated and 140 downregulated genes. They were also the genomes with the most significant changes in transcriptome gene expression, mainly constituting cytoplasmic, synaptic structures and transporters, and involved in amino acid and carbon metabolism. There were 42 differentially expressed circRNAs, including 25 upregulated genes and 17 downregulated genes, mainly involved in cell composition, growth, differentiation, and division. There were only 10 differentially expressed miRNAs genes, all upregulated and mainly involved in the inflammatory response pathway. Proteome identification showed 79 differentially expressed proteins. KEGG enrichment analysis showed that it was mainly involved in the N-glycan biosynthesis pathway.

Conclusion

We discovered that differentially regulated genes (lncRNAs, circRNAs, and miRNAs) were primarily associated with neuronal reflexes and synaptic signaling, including neurotransmitter transmission, ion signaling pathway conduction, neuronal projection, and synaptic vesicle circulation. They affected inflammatory factors and other metabolic pathways. This finding could be explored in future studies.

The mmu_circ_003062, hsa_circ_0075663/miR-490-3p/CACNA1H axis mediates apoptosis in renal tubular cells in association with endoplasmic reticulum stress following ischemic acute kidney injury

BACKGROUND

While recent studies have suggested a potential involvement of circRNAs in acute kidney injury (AKI) after ischemia, mmu_circ_003062 role is undetermined.

METHODS

The levels of mmu_circ_003062, miR-490-3p, CACNA1H, GRP78, CHOP and hsa_circ_0075663 were detected by Relative qPCR in Boston University mouse proximal tubule (BUMPT) cells, mouse kidneys, and human renal tubular epithelial (HK-2) cells. Moreover, the levels of hsa_circ_0075663 in serum and urine of patients with AKI following cardiopulmonary resuscitation (CPR) were detected by absolute quantitative PCR. Western blot was used to detect the relative expression of the protein. The function and regulatory mechanism of mmu_circ_003062 and hsa_circ_0075663 were investigated through a series of in vitro and in vivo experiments, including bioinformatic prediction, luciferase reporter assays, FISH, FCM, TUNEL staining, and H&E staining.

RESULTS

It was found that mmu_circ_003062, hsa_circ_0075663 mediated apoptosis after ischemia/reperfusion (I/R) by interaction with miR-490-3p to enhance CACNA1H expression, thereby leading to the upregulation of endoplasmic reticulum stress (ERS)-relevant proteins GRP78 and CHOP. Ultimately, mmu_circ_003062 downregulation significantly ameliorated ischemic AKI by modulating the miR-490-3p/CACNA1H/GRP78 and CHOP pathway. Furthermore, the plasma and urinary levels of hsa_circ_0075663 in patients with AKI following CPR were significantly higher than non-AKI patients, exhibited a strongly correlation with serum creatinine.

CONCLUSION

The involvement of mmu_circ_003062, hsa_circ_0075663/miR-490-3p/CACNA1H/GRP78 and CHOP axis is significant in the development of ischemic AKI. Moreover, hsa_circ_0075663 has potential as an early diagnostic biomarker.

circ_PPAPDC1A promotes Osimertinib resistance by sponging the miR-30a-3p/ IGF1R pathway in non-small cell lung cancer (NSCLC)

BACKGROUND

Recent evidence has demonstrated that abnormal expression and regulation of circular RNA (circRNAs) are involved in the occurrence and development of a variety of tumors. The aim of this study was to investigate the effects of circ_PPAPDC1A in Osimertinib resistance in NSCLC.

METHODS

Human circRNAs microarray analysis was conducted to identify differentially expressed (DE) circRNAs in Osimertinib-acquired resistance tissues of NSCLC. The effect of circ_PPAPDC1A on cell proliferation, invasion, migration, and apoptosis was assessed in both in vitro and in vivo. Dual-luciferase reporter assay, RT-qPCR, Western-blot, and rescue assay were employed to confirm the interaction between circ_PPAPDC1A/miR-30a-3p/IGF1R axis.

RESULTS

The results revealed that circ_PPAPDC1A was significantly upregulated in Osimertinib acquired resistance tissues of NSCLC. circ_PPAPDC1A reduced the sensitivity of PC9 and HCC827 cells to Osimertinib and promoted cell proliferation, invasion, migration, while inhibiting apoptosis in Osimertinib-resistant PC9/OR and HCC829/OR cells, both in vitro and in vivo. Silencing circ_PPAPDC1A partially reversed Osimertinib resistance. Additionally, circ_PPAPDC1A acted as a competing endogenous RNA (ceRNA) by targeting miR-30a-3p, and Insulin-like Growth Factor 1 Receptor (IGF1R) was identified as a functional gene for miR-30a-3p in NSCLC. Furthermore, the results confirmed that circ_PPAPDC1A/miR-30a-3p/IGF1R axis plays a role in activating the PI3K/AKT/mTOR signaling pathway in NSCLC with Osimertinib resistance.

CONCLUSIONS

Therefore, for the first time we identified that circ_PPAPDC1A was significantly upregulated and exerts an oncogenic role in NSCLC with Osimertinib resistance by sponging miR-30a-3p to active IGF1R/PI3K/AKT/mTOR pathway. circ_PPAPDC1A may serve as a novel diagnostic biomarker and therapeutic target for NSCLC patients with Osimertinib resistance.

The potential role of circular RNAs -regulated PI3K signaling in non-small cell lung cancer: Molecular insights and clinical perspective

Non-small cell lung cancer (NSCLC), accounting for more than 80% of all cases, is the predominant form of lung cancer and the leading cause of cancer-related deaths worldwide. Significant progress has been made in diagnostic techniques, surgical interventions, chemotherapy protocols, and targeted therapies at the molecular level, leading to enhanced treatment outcomes in patients with NSCLC. Extensive evidence supports the use of circular RNAs (circRNAs), a specific category of naturally occurring non-coding small RNAs (ncRNAs), for the diagnosis, monitoring of treatment efficacy, and assessment of survival in NSCLC. CircRNAs have been identified to play significant roles in various aspects of cancer formation, either as tumor suppressors or tumor promoters, contributing to cancer development through several signaling pathways, including the phosphoinositide 3-kinases (PI3Ks) pathway. This pathway is well-established because of its regulatory role in essential cellular processes. CircRNAs regulate the PI3K/AKT pathway by targeting diverse cellular elements. This review aims to provide insight into the involvement of several circRNAs linked to the PI3K/AKT pathway in NSCLC.

Human circular RNA hsa_circ_0000231 clinical diagnostic effectiveness as a new tumor marker in gastric cancer

BACKGROUND

Owing to the subtlety of initial symptoms associated with gastric cancer (GC), the majority of patients are diagnosed at later stages. Given the absence of reliable diagnostic markers, it is imperative to identify novel markers that exhibit high sensitivity and specificity. Circular RNA, a non-coding RNA, plays an important role in tumorigenesis and development and is well expressed in body fluids.

AIMS

In this study, we aimed to identify hsa_circ_0000231 as a new biomarker for the diagnosis of GC and to assess its clinical diagnostic value in serum.

METHODS AND RESULTS

The stability and correctness of hsa_circ_0000231 was determined by agarose gel electrophoresis, Rnase R assay and Sanger sequencing. Real-time quantitative polymerase chain reaction (qRT-PCR) was designed to discover the expression level of hsa_circ_0000231 and whether it has dynamic serum monitoring capability. The correlation between hsa_circ_0000231 and clinicopathological parameters was analyzed by collecting clinical and pathological data from GC patients. In addition, diagnostic efficacy was assessed by constructing receiver operating characteristic curves (ROC). Hsa_circ_0000231 exhibits a stable and consistently expressed structure. In GC serum, cells, and tissues, it demonstrates reduced expression levels. Elevated expression levels observed postoperatively suggest its potential for dynamic monitoring. Additionally its expression level correlates with TNM staging and neuro/vascular differentiation. The area under ROC curve (AUC) for hsa_circ_0000231 is 0.781, indicating its superior diagnostic value compared to CEA, CA19-9, and CA72-4. The combination of these four indicators enhances diagnostic accuracy, with an AUC of 0.833.

CONCLUSIONS

The stable expression of hsa_circ_0000231 in the serum of gastric cancer patients holds promise as a novel biomarker for both the diagnosis and dynamic monitoring of GC.

Current advances in circular RNA detection and investigation methods: Are we running in circles?

Circular RNAs (circRNAs), characterized by their closed-loop structure, have emerged as significant transcriptomic regulators, with roles spanning from microRNA sponging to modulation of gene expression and potential peptide coding. The discovery and functional analysis of circRNAs have been propelled by advancements in both experimental and bioinformatics tools, yet the field grapples with challenges related to their detection, isoform diversity, and accurate quantification. This review navigates through the evolution of circRNA research methodologies, from early detection techniques to current state-of-the-art approaches that offer comprehensive insights into circRNA biology. We examine the limitations of existing methods, particularly the difficulty in differentiating circRNA isoforms and distinguishing circRNAs from their linear counterparts. A critical evaluation of various bioinformatics tools and novel experimental strategies is presented, emphasizing the need for integrated approaches to enhance our understanding and interpretation of circRNA functions. Our insights underscore the dynamic and rapidly advancing nature of circRNA research, highlighting the ongoing development of analytical frameworks designed to address the complexity of circRNAs and facilitate the assessment of their clinical utility. As such, this comprehensive overview aims to catalyze further advancements in circRNA study, fostering a deeper understanding of their roles in cellular processes and potential implications in disease. This article is categorized under: RNA Methods > RNA Nanotechnology RNA Methods > RNA Analyses in Cells RNA Methods > RNA Analyses In Vitro and In Silico.

METTL3 modification of circStk4 affects mouse glomerular messangial cell autophagy, proliferation and apotosis by regulating miR-133a-3p/C1 axis

OBJECTIVE

The study aimed to explore the impact of N6-methyladenosine (m6A) modification in circStk4 on glomerular mesangial cells (GMCs) autophagy, proliferation and apoptosis.

METHODS

The interactions between circStk4 and miR-133a-3p, miR-133a-3p and C1 were demonstrated through luciferase reporter assays. The circStk4 localization was analyzed using fluorescence in situ hybridization and nuclear/cytosol fractionation assays. Colorimetric assays, MeRIP-qPCR, and western blot (WB) were employed to confirm the m6A modification of circStk4 and identify the key methylation enzyme. RT-qPCR was conducted to determine the impact of METTL3 on the circStk4 RNA expression. Additionally, CCK-8, flow cytometry, transmission electron microscopy, immunofluorescence, WB and RT-qPCR were employed to investigate the effects of METTL3 or circStk4 on the proliferation, autophagy and apoptosis of GMCs. Enzyme-linked immunosorbent assay was utilized to assess the inflammatory factors.

RESULTS

m6A modifications were found in circStk4 and METTL3 was a key methylating enzyme. Furthermore, it was observed that circStk4 competitively bound miR-133a-3p and increased C1 levels. Silencing circStk4 resulted in decreased GMCs proliferation, increased autophagy and apoptosis, and reduced inflammation levels. Additionally, METTL3 played a role in inhibiting GMCs proliferation and promoting autophagy and apoptosis by regulating the circStk4 expression. On verifying the interplay between autophagy, proliferation and apoptosis, and found that the inhibition of autophagy led to an increase in cell proliferation and a decrease in apoptosis.

CONCLUSION

m6A modification of circStk4 mediated by METTL3 influenced circStk4 expression and impacted autophagy, proliferation and apoptosis in GMCs via the miR-133a-3p/C1 axis. This discovery introduces a novel therapeutic approach for CGN treatment.

The therapeutic potential of circular RNA in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is among the most aggressive subtypes of the disease that does not express estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. Circular RNAs (circRNAs) are a type of non-coding RNA with a circular shape formed by non-standard splicing or reverse splicing. Numerous circRNAs exhibit abnormal expression in various malignancies, showing their critical role in the emergence and growth of tumors. Recent studies have shown evidence supporting the idea that certain circRNAs regulate the proliferation and metastasis of TNBC. In addition, circRNAs alter metabolism and the immune microenvironment to promote or inhibit the development of TNBC. Notably, circRNAs may affect the efficacy of clinical drug therapy, serve as therapeutic targets, and be used as molecular biomarkers in the future. Herein, we will first summarize the biogenesis and function of circRNAs. Then, we will explain current research on circRNAs related to TNBC and their potential to serve as therapeutic targets or biomarkers for future drug development, providing a new direction and idea for TNBC therapy.

Circ_0003945: an emerging biomarker and therapeutic target for human diseases

Due to the rapid development of RNA sequencing techniques, a circular non-coding RNA (ncRNA) known as circular RNAs (circRNAs) has gradually come into focus. As a distinguished member of the circRNA family, circ_0003945 has garnered attention for its aberrant expression and biochemical functions in human diseases. Subsequent studies have revealed that circ_0003945 could regulate tumor cells proliferation, migration, invasion, apoptosis, autophagy, angiogenesis, drug resistance, and radio resistance through the molecular mechanism of competitive endogenous RNA (ceRNA) during tumorigenesis. The expression of circ_0003945 is frequently associated with some clinical parameters and implies a poorer prognosis in the majority of cancers. In non-malignant conditions, circ_0003945 also holds considerable importance in diseases pathogenesis. This review aims to recapitulate molecular mechanism of circ_0003945 and elucidates its potential as a diagnostic and therapeutic target in neoplasms and other diseases.

Qingjie Huagong decoction inhibits pancreatic acinar cell pyroptosis by regulating circHipk3/miR-193a-5p/NLRP3 pathway

BACKGROUND

Safer and more effective drugs are needed for the treatment of acute pancreatitis (AP). Qingjie Huagong decoction (QJHGD) has been applied to treat AP for many years and has shown good clinical effects. However, the potential mechanism has not yet been determined.

PURPOSE

To investigate the role and underlying mechanism of the effects of QJHGD on AP both in vitro and in vivo.

METHODS

QJHGD was characterized by UHPLC-Q-Orbitrap-MS. The protective effect of QJHDG and the underlying mechanism were investigated in MPC-83 cells in vitro. A caerulein-induced AP model was established to evaluate the protective effect of QJHGD in mice. CCK-8 assays were used to detect cell viability. The contents of inflammatory mediators were determined by ELISA. Expression levels of circRNA, miRNA and mRNA were determined by qRT-PCR. Protein expression was determined using Western blot. Pancreatic tissues were assessed by hematoxylin and eosin staining as well as immunohistochemical and immunofluorescence analyses. Pull-down and luciferase activity assays were performed to determine the regulatory relationships of circHipk3, miR-193a-5p and NLRP3.

RESULTS

Our results confirmed that mmu-miR-193a-5p was sponged by mmu-circHipk3, and NLRP3 was a target of miR-193a-5p. In vitro experiments showed that QJHGD enhanced MPC-83 cell viability by regulating circHipk3 sponging mir-193a-5 targeting NLRP3 and inhibiting pyroptosis-related factors. Finally, we showed that QJHGD ameliorated pancreatic tissue injury in AP mice via this pathway.

CONCLUSION

This study demonstrate that QJHDG exerted its anti-AP effects via the circHipk3/miR-193a-5p/NLRP3 pathway, revealing a novel mechanism for the therapeutic effect of QJHDG on AP.

Hsa_circ_0010882 facilitates hepatocellular carcinoma progression by modulating M1/M2 macrophage polarization

Hepatocellular carcinoma (HCC) is one common malignant tumour with a high immunosuppressive tumour microenvironment and poor outcomes. This study investigated the influence of hsa_circ_0010882 on M1/M2 macrophage polarization in the progression of HCC. A total of 125 paired tissue specimens from HCC patients who underwent hepatectomy were collected. M1 and M2 phenotypes macrophages were induced using THP-1. After co-cultured with macrophages and transfected HCC cells, the viability, migration and invasion of HCC cells were detected by cellular experiments. Bioinformatic databases and dual-luciferase reporter assays were used to predict and validate the interaction between circ_0010882 and miR-382. Expression of circ_0010882 was increased in HCC tissues and associated with shorter overall survival outcomes. The mRNA expression of M2 macrophage markers Arg-1, CD163 and CD206 were elevated in HCC tissues. Interfering with circ_0010882 increased M1-type macrophage markers (TNF-α and iNOS) while decreasing M2-type macrophage markers (Arg-1 and CD206). Silencing of circ_0010882 strengthened the capacity of M1 macrophages to suppress HCC cell viability, migration capacities and invasion potential while reducing the ability of M2 macrophages to promote above cellular abilities. MiR-382 was a direct target miRNA of circ_0010882. The circ_0010882 expression was increased in HCC tissues and associated with poor prognosis of HCC patients. Silencing of circ_0010882 inhibits macrophage M2 polarization in HCC progression by regulating miR-382 expression. Circ_0010882 may serve as a biomarker to provide novel strategies for the treatment of HCC and patient rehabilitation, thereby improving the prognosis of patients.

Role of circPSEN1 in carbon black and cadmium co-exposure induced autophagy-dependent ferroptosis in respiratory epithelial cells

Carbon black and cadmium (Cd) are important components of atmospheric particulate matter and cigarette smoke that are closely associated with the occurrence and development of lung diseases. Carbon black, particularly carbon black nanoparticles (CBNPs), can easily adsorbs metals and cause severe lung damage and even cell death. Therefore, this study aimed to explore the mechanisms underlying the combined toxicity of CBNPs and Cd. We found that the combined exposure to CBNPs and Cd promoted significantly greater autophagosome formation and ferroptosis (increased malonaldehyde (MDA), reactive oxygen species (ROS), and divalent iron ions (Fe2+) levels and altered ferroptosis-related proteins) compared with single exposure in both 16HBE cells (human bronchial epithelioid cells) and mouse lung tissues. The levels of ferroptosis proteins, transferrin receptor protein 1 (TFRC) and glutathione peroxidase 4 (GPX4), were restored by CBNPs-Cd exposure following treatment with a 3-MA inhibitor. Additionally, under CBNPs-Cd exposure, circPSEN1 overexpression inhibited increases in the autophagy proteins microtubule-associated protein 1 light chain 3 (LC3II/I) and sequestosome-1 (P62). Moreover, increases in TFRC and Fe2+, and decreases in GPX4were inhibited. Knockdown of circPSEN1 reversed these effects. circPSEN1 interacts with autophagy-related gene 5 (ATG5) protein and upregulates nuclear receptor coactivator 4 (NCOA4), the co-interacting protein of ATG5, thereby degrading ferritin heavy chain 1 (FTH1) and increasing Fe2+ in 16HBE cells. These results indicated that the combined exposure to CBNPs and Cd promoted the binding of circPSEN1 to ATG5, thereby increasing autophagosome synthesis and ATG5-NCOA4-FTH1 axis activation, ultimately inducing autophagy-dependent ferroptosis in 16HBE cells and mouse lung tissues. This study provides novel insights into the toxic effects of CBNPs and Cd in mixed pollutants.

Allicin inhibits the biological activities of cervical cancer cells by suppressing circEIF4G2

Allicin is a safe herbal extract believed to have antitumor effects, which, however, remain unclear. The aim of the present work was to discuss Allicin antitumor effects on cervical cancer using cell experiments. Using Hela and Siha to our research objectives in our study, first step, difference concentration of Allicin (20, 40, and 80 μM) treated Hela and Siha cell lines, and next step, discuss circEIF4G2 effects in Allicin antitumor effects in Hela and Siha cell lines; the cell proliferation and EdU-positive cell number by CCK-8 and EdU staining; cell apoptosis rate by flow cytometry; invasion cell number by transwell assay; wound healing rate by wound healing assay; and relative mRNA and protein levels using qRT-PCR and WB assay. With Allicin supplement, the cell proliferation and EdU-positive cell number were significantly depressed with cell apoptosis rate significantly increasing; invasion cell number and wound healing rate significantly suppressed with circEIF4G2 mRNA expression significantly down-regulation (p < .05, respectively). However, there was no significant difference among Allicin, si-circEIF4G2, and Allicin+si-circEIF4G2 in cell biological activities including cell proliferation, apoptosis, invasion and migration, and relative gene and protein expression. Allicin depresses biological activities of cervical cancer cells through down-regulating circEIF4G2/HOXA1/AKT/mTOR.

Botulinum Toxin Type A Alleviates Androgenetic Alopecia by Inhibiting Apoptosis of Dermal Papilla Cells via Targeting circ_0135062/miR-506-3p/Bax Axis

Botulinum toxin type A (BTXA) has the potential to treat androgenetic alopecia (AGA); however, its impact on the apoptosis of dermal papillary cells (DPCs) is not yet fully understood. Noncoding RNAs play a crucial role in AGA. In this study, we investigated the potential mechanism by which BTXA alleviates apoptosis induced by dihydrotestosterone (DHT) in DPCs. We assessed the mRNA levels of circ_0135062, miR-506-3p, and Bax using qRT-PCR. Binding interactions were analyzed using RNA pulldown and dual-luciferase assays. Cell viability was determined using a cell counting kit-8 assay, and cell apoptosis was assessed using flow cytometry, TUNEL assays, and western blotting. Our findings revealed that BTXA inhibited the apoptosis of DPCs treated with DHT. Moreover, circ_0135062 overexpression counteracted the protective effect of BTXA on DHT-treated DPCs. MiR-506-3p was found to interact with Bax and inhibit apoptosis in DPCs by suppressing Bax expression in response to DHT-induced damage. Furthermore, circ_0135062 acted as a sponge for miR-506-3p, thereby inhibiting the targeting of Bax expression by miR-506-3p. In conclusion, BTXA exhibited an antiapoptotic effect on DHT-induced DPC injury via the circ_0135062/miR-506-3p/Bax axis.Level of Evidence II This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .