IUBMB Life最新文献

Exosomes, the cargo of circRNA, are crucial in cancer cell–tumor microenvironment communication. circSMARCC1 exerts a pro-tumor effect. However, this role has not been previously reported in gastric cancer (STAD). This study explores the role of STAD cell-derived exosomal circSMARCC1 in promoting macrophage M2 polarization. In this study, exosomes from the peripheral blood of STAD patients and AGS cells were extracted and identified. THP-1 cells were differentiated into macrophages with phorbol 12-myristate 13-acetate (PMA) and polarized to the M2 phenotype by IL-4 and IL-13. circSMARCC1 expression was analyzed in STAD tissues, cell lines, and patient-derived exosomes. The biological function of circSMARCC1 in STAD cells was evaluated by CCK-8, EdU, and Transwell assays. The role of circSMARCC1 and U2 small nuclear RNA auxiliary factor 2 (U2AF2) in regulating macrophage M2 polarization was verified by bioinformatics methods, qRT-PCR, Western blot, ELISA, and a nude mouse tumor-bearing model. Our findings demonstrated that circSMARCC1 was upregulated in STAD and associated with macrophage immune infiltration. circSMARCC1 knockdown suppressed the malignant phenotypes of STAD cells and M2 macrophage polarization, whereas its overexpression led to the contrary result. Animal experiments further confirmed circSMARCC1 regulated tumor growth and macrophage M2 polarization. Importantly, exosomal circSMARCC1 in STAD patients was increased. Knockdown of circSMARCC1 in AGS cells reduced its level in secreted exosomes and inhibited M2 polarization, whereas overexpression produced the opposite effect. Mechanistically, circSMARCC1 upregulated U2AF2 expression through exosomes to promote macrophage M2 polarization. Collectively, STAD cell-derived exosomes induced macrophage M2 polarization to promote STAD progression through circSMARCC1.

All-trans retinoic acid (ATRA), a bioactive metabolite of vitamin A, is vital for cell development and gene transcription. Coronary artery calcium (CAC) is a risk factor for cardiovascular events but lacks predictive biomarkers and effective treatments. We investigated the correlation between serum ATRA levels and CAC scores in patients, and the potential of ATRA supplementation to alleviate vascular calcification. Proteomic analysis was conducted on rat primary vascular smooth muscle cells (VSMCs) cultured under calcifying conditions. Serum samples from 88 patients with/without CAC were analyzed for ATRA levels and CAC scores. In vivo, vascular classification was established in mice fed a high-fat and high-purine diet with vitamin D3 injection. In vitro, VSMCs were cultured with medium containing 10 mM phosphorus and 3 mM calcium with/without TGF-β (20 and 5 μg/mL) to induce calcification. Single-cell RNA sequencing was performed on mouse aortas. Proteomics showed synchronous downregulation in enzymes involved in ATRA synthesis under calcifying conditions. Serum ATRA levels were negatively correlated with CAC scores in patients. ROC curve analysis revealed an AUC of 0.9135 for ATRA (sensitivity: 73.9%, specificity: 93.3%, and optimal cutoff value: 96.64 pg/mL). In vivo, ATRA alleviated aortic calcification and downregulated RUNX2 and BMP2. In vitro, ATRA reduced calcium deposition and TNF-α and IL-6 in VSMCs. Single-cell RNA sequencing revealed that ATRA downregulated the TNF-α signaling pathways in VSMCs. Our results suggest that low serum ATRA levels may serve as an indicator of vascular calcification, and ATRA supplementation could be an effective therapy.

Studies have shown that Legumain (LGMN) is a potential protease for immunosuppression in glioblastoma multiforme (GBM). Moreover, the elevated expression of LGMN in different types of cancers is linked to an unfavorable prognosis. However, it is still not clear about the expression of LGMN in gliomas, its links with clinical situations, the ways of immune infiltration, and its significance for the prognosis. The glioma data were obtained from online databases. We verified the expression, clinical correlation, immune microenvironment, and prognostic model of LGMN by combining RNA-seq, genomic data, spatial transcriptomics (ST-seq), proteomics data, scRNA-seq data, and RT-qPCR experiments. Moreover, we explored the biological processes of LGMN through enrichment analysis and conducted immunological analysis. In comparison with normal tissues, glioma tissues show enhanced expression of LGMN both at the gene and protein levels. The experimental findings indicated that the mRNA expression of LGMN was markedly increased in U87 and U251 cells compared with those in NHA cells. Glioma patients' overall survival (OS) may be reliably predicted by the expression of LGMN. Based on a functional enrichment study, LGMN is linked to biological functions such as cell signal transduction and immunology. LGMN has a positive relationship with immune checkpoints in glioma and is additionally related to immune infiltration. scRNA-seq analysis revealed LGMN expression in cell types like Mono/Macrophages, microglia, and malignant cells. LGMN expressed in glioma is intricately linked to molecular pathology, and has significant bearings on clinical prognosis. Meanwhile, there is a connection between LGMN expression and glioma immunity. Therefore, LGMN is a novel target for independent prognosis and immunotherapy strategies in glioma.

PIWI-interacting RNAs (piRNAs) have emerged as key gene regulators in diverse biological processes. Earlier believed to be germline-specific, these endogenous small non-coding RNAs (~26–32 nucleotides) have now been identified to play an active role in non-gonadal tissues as well. piRNAs in association with PIWI proteins bind to their targets and form the piRISC complex that especially regulates transposable elements (TEs) in the germline. However, after further experiments, piRNAs have been found to target and modulate the expression of non-TEs as well. Several high-throughput technologies have identified piRNA target sites in different cells and tissues of various model organisms, but all these studies have demonstrated discrete patterns of sequence complementarity between piRNA and its target. This indicates that the principle of piRNA targeting is not uniform, unlike miRNAs, due to the lack of precise knowledge regarding their targets. Further, the co-evolution of the piRNA pathway and its targeted transposons in a species-specific manner has created distinct differences in the piRNA targeting features between different species, specifically invertebrates and mammals. In this review, we focus on the current high-throughput techniques that have been used to understand the sequence-specific features that influence structural conformations favoring piRNA-target duplex formation and target cleavage. Overall, it has been observed that modulation in the degree of sequence-based complementarity between piRNA and its target sequence choreographs piRNA target interaction, which in turn enables PIWI to leverage the vast pool of piRNAs in restricting TE escape from surveillance in a sophisticated manner.

Accumulating evidence has confirmed that snoRNAs exert a role in a variety of cancers; however, the role of SNORA33 in clear cell renal cell carcinoma (ccRCC) remains unclear. This study was aimed at elucidating the role and mechanism of SNORA33 in the tumorigenesis and progression of ccRCC. The snoRNAs expression matrices were obtained from the public TCGA and SNORic databases. Kaplan–Meier analysis was employed to investigate the survival of patients with ccRCC presenting different SNORA33 expression. The prognostic value of SNORA33 in ccRCC was examined using Cox univariate and multivariate analyses. A series of in vitro experiments were conducted to explore the functional role of SNORA33 in ccRCC. Gene set enrichment analysis (GSEA) and western blot were used to explore and validate the involved mechanisms. SNORA33 was highly expressed in patients with ccRCC and was correlated with poor prognosis. In addition, SNORA33 was intimately associated with the infiltration of diverse immune cells and positively correlated with the immune score as well as the expression levels of multiple immune checkpoint molecules, serving as a potential biomarker for immunotherapy prediction. The findings of in vitro experiments indicated that SNORA33 was capable of promoting the proliferation, invasion, migration, and resistance to sunitinib in ccRCC. SNORA33 was highly expressed in ccRCC and indicated an adverse prognosis. SNORA33 was capable of facilitating the progression, invasion, metastasis, and resistance to sunitinib of ccRCC cells through mediating the JAK/STAT pathway.

Vascular calcification (VC) is a significant pathological feature of atherosclerosis, contributing to cardiovascular morbidity and mortality, particularly in populations with diabetes and chronic kidney disease (CKD). This review examines the pivotal role of macrophages in the development and progression of VC within atherosclerotic plaques. We explore the diverse phenotypes of macrophages, particularly the pro-inflammatory M1 and anti-inflammatory M2 types, and their distinct functions in modulating vascular smooth muscle cell (VSMC) behavior. M1 macrophages promote osteogenic signaling through the secretion of pro-inflammatory cytokines and growth factors, such as oncostatin M (OSM) and bone morphogenetic proteins (BMP), which facilitate VSMC transdifferentiation and calcification. Conversely, M2 macrophages exhibit protective properties that may mitigate excessive calcification. Furthermore, we discuss the intricate balance of these macrophage populations in atherosclerotic lesions and their influence on osteoclastic differentiation, which can either enhance or inhibit the resorption of calcified deposits. Recent findings on the involvement of microRNAs (miRNAs) in regulating macrophage activation and their impact on VC highlight potential therapeutic targets for mitigating this process. By elucidating the cellular and molecular mechanisms underpinning macrophage-mediated calcification, this review aims to provide insights into the dual roles of macrophages in atherosclerosis and their significance as potential therapeutic targets. Understanding these dynamics may lead to innovative strategies for preventing VC and improving cardiovascular health outcomes, particularly in patients with diabetes and CKD.

Metabolic dysfunction-associated fatty liver disease (MAFLD), defined by fat accumulation in more than 5% of hepatocytes, is a common metabolic syndrome worldwide. However, 30%–40% of MAFLD cases progress to metabolic dysfunction-associated steatohepatitis (MASH), increasing the importance of the disease. MicroRNAs (miRNAs), non-coding RNA molecules approximately 21 nucleotides long, are used as biomarkers in many diseases and play a crucial role in regulating cellular processes by affecting gene expression. It is also known that miRNAs are effective in the progression of MASH and its profile depends on the stage of the disease. Therefore, we determined the relationship between MASH and miRNA profiles in an in vivo trial using an established model of cholesterol-induced MASH in rabbits. We also evaluated the impact of α-tocopherol, which is known to have a protective effect in MAFLD/MASH transition, on miRNA profiles. Regarding the limited information using rabbits, we first performed miRNA screening and identified miRNAs that are already described in rabbits or other organisms as well as the putative ones. Among those, two putative miRNAs (miR-230 and miR-1146) determined by sequencing may be important in the diagnosis and treatment of the disease. Furthermore, levels of five miRNAs (miR-122-5p, miR-199-5p, miR-145-5p, miR-27b-3p, miR-34a-5p) and their relevance in the pathogenesis of MASH were determined by RT-PCR and target gene prediction, respectively. In conclusion, the present study provides novel information regarding dysregulated miRNAs in high-cholesterol diet-induced MASH and the impact of α-tocopherol.

Lung injury and fibrosis involve a complex interplay between inflammation and coagulation, with tissue factor (TF/CF-III/Thromboplastin/CD142) acting as a crucial mediator. Despite its known role in initiating the extrinsic coagulation cascade, TF's contribution to fibrin deposition in lung injury remains underexplored. This study examines the dysregulation of the extrinsic coagulation cascade and its pathological implications in lung injury, contributing to the progression of pulmonary fibrosis (PF). Utilizing bleomycin (BLM), transforming growth factor-β (TGF-β), and TF models, we systematically investigate coagulation-driven inflammatory responses in lung pathology. By integrating in vitro (A549 and Beas2b epithelial cell models) and in vivo (C57BL/6 murine models) approaches, this study elucidates TF-mediated molecular mechanisms driving inflammation, fibrin deposition, endothelial dysfunction, and fibrotic remodeling. Protein-protein interaction (PPI) network analysis highlights functional associations between coagulation factors (CFs) and inflammatory mediators, reinforcing their involvement in lung homeostasis. Also, gene enrichment analysis identifies key biological processes, including coagulation, fibrinolysis, and immune activation, emphasizing their role in disease progression. In A549 and Beas2b epithelial cells, CF-III, CF-VII, and CF-X expression increased significantly, with A549 cells exhibiting a heightened pro-coagulant response. Elevated IL-6, TNF-α, and IL-1β levels suggest an inflammatory amplification tied to TF activation. Immunofluorescence analysis demonstrates marked TF upregulation and TNF-α activation, reinforcing the interplay between coagulation pathways and inflammatory cytokine signaling. Histological assessments (H&E, and Masson Trichrome [MT] staining) in murine lung tissues confirm fibrotic and inflammatory changes, reinforcing TF's pathogenic role. Our findings establish TF as a key molecular driver of thrombo-inflammatory lung injury, providing potential therapeutic targets to mitigate fibrosis and improve patient outcomes.