Search Results (3,965)

Type 2 diabetes mellitus (T2DM) is known to increase the risk of fragility fractures; however, the underlying mechanism is still elusive. Reduced miR-155 and elevated RHOA are known to drive bone resorption, but their role in T2DM remains unclear. This study investigates bone remodeling imbalances in T2DM through miR-155 and RHOA expression profiling. Three-month-old female Wistar rats were fed a high-calorie diet for 3 weeks, followed by intraperitoneal injections of two lower doses of streptozotocin at weekly intervals to induce T2DM. Bone analysis from diabetic rats tested using qRT-PCR showed significantly reduced miR-155 levels and elevated RHOA. Histological analysis showed a 12.65% increase in Tb.Sp, 10.07% decrease in Tb.Th, and significant increase (p < 0.05) in apoptotic osteocytes. The bone turnover marker CTx-1 level was increased by 20.84%, and RANKL levels were significantly increased in T2DM. IL-1β and TNF-α were increased in T2DM. Bone resorption is more likely to occur in T2DM as both IL-1β and TNF-α work synergistically to promote osteoclastogenesis. MiR-155 could be an important modulator of bone remodeling in T2DM and a potential therapeutic target for diabetic osteopathy. Full article

This study aims to investigate the molecular mechanisms underlying germ cell tumors (GCTs), focusing specifically on seminomas and teratomas. By analyzing gene expression profiles and miRNA interactions, the goal is to identify key regulatory miRNAs and signaling pathways that differentiate these tumor types and could serve as important regulators for therapy development. Raw data for seminomas and teratomas were extracted from the GEO database, and gene hubs were identified using STRING and Gephi. Signaling pathways and functional annotations were analyzed using miRPathDB, while miRNA–gene interactions were explored via miRWalk. Hub miRNAs were filtered and confirmed using miRDB. This study highlights significant changes in gene expression diversity between tumor and normal gonadal tissues, providing insights into the molecular dynamics of seminomas and teratomas. Distinctions between seminomas and teratomas were identified, shifting the focus toward miRNAs to discover more precise and novel therapeutic approaches. The hub genes of seminomas and teratomas were identified separately. MiRNAs targeting these hub genes were also determined and confirmed. These miRNAs collectively influence essential oncogenic pathways—confirming hsa-miR-138-5p as a regulator of pathways such as Hippo signaling, transcriptional misregulation in cancer, and microRNA cancer signaling in seminomas, and hsa-miR-200b-3p as a regulator of p53 signaling, T cell receptor signaling, and pathways including PI3K/AKT, MAPK/ERK, and Wnt/β-catenin in teratomas—confirming their potential as promising candidates for subtype-specific therapeutic intervention. MiRNAs identified through bioinformatics analyses, and their predicted regulatory roles in key oncogenic pathways, represent potential therapeutic targets or regulators of biological processes. However, further experimental validation is needed to confirm these findings. Full article

Background/Objectives: Despite advances in diagnosis and treatment, colorectal cancer (CRC) remains one of the most prevalent and challenging malignancies worldwide. The dysregulation of microRNAs (miRNAs) has emerged as a critical factor in CRC onset, progression, and therapeutic resistance. This study aims to provide an overview of global research trends on miRNAs in CRC, (i) identifying the most studied miRNAs, (ii) exploring under-investigated areas, and (iii) highlighting emerging themes and potential future directions. Methods: To assess the evolution of the global miRNA–CRC research trends, we conducted a bibliometric analysis of 828 CRC–miRNA-focused articles published between 2008 and 2024, sourced from the Scopus database. Bibliometric mapping was performed using the R/Bibliometrix package and by leveraging a customized Python-based pipeline, which is useful for extracting and validating miRNA identifiers (miRNA IDs) based on the miRBase database. This miRNA ID-related approach enabled us to systematically identify the most frequently studied miRNAs over time while highlighting underexplored miRNA. Results: The analysis revealed a substantial and accelerating publication growth rate, delineating three major phases in CRC–miRNA research. China emerged as the leading contributor in terms of the publication volume. miR-21, miR-34a, and miR-195-5p were among the most frequently studied miRNAs, underscoring their relevance to CRC biology and therapy. Keyword and citation analyses identified key thematic areas, such as cell proliferation, epithelial–mesenchymal transition, and chemoresistance, especially to oxaliplatin and 5-fluorouracil. Emerging research frontiers included ferroptosis, ceRNA networks, and exosome-mediated miRNA transport. An analysis of the collaborations indicated strong intra-national collaborations, with room for expanding international research networks. Conclusions: This study provides an in-depth bibliometric landscape of the CRC-related miRNA research by highlighting influential studies and journals while identifying gaps and underexplored topics. These insights offer valuable guidance for future translational and clinical research on this topic. Full article

High-throughput transcriptomic analyses have identified numerous candidate miRNA–mRNA and long non-coding RNA (lncRNA) regulatory networks in teleosts, but most remain without systematic functional validation or mechanistic definition. Here, by interrogating miRNA–lncRNA networks in rainbow trout (Oncorhynchus mykiss) gonads, we define their roles in meiotic progression and gonadal development. From preliminary screening, we identified lncRNA74687 as a central node and characterised its function. Subcellular localisation showed predominant nuclear enrichment of lncRNA74687 in gonadal cells. Dual-luciferase assays confirmed miR-15a-5p targeting of Cyclin E (CCNE1) and lncRNA74687. Functional studies showed that concurrent overexpression of lncRNA74687 and inhibition of miR-15a-5p synergistically increased the CCNE1 protein to maximal levels. 5-ethynyl-2′-deoxyuridine (EdU) assays showed that knockdown of lncRNA74687 and CCNE1 in rainbow trout gonadal (RTG-2) cells reduced proliferation by 36.4% and 41.2%, respectively (p < 0.05). Immunofluorescence indicated that lncRNA74687 increased Synaptonemal Complex Protein 1 (SYCP1) signalling 6.93-fold in gonadal cells via CCNE1. In vivo, lncRNA74687 knockdown increased miR-15a-5p expression 6.34-fold relative to the wild-type controls (p < 0.01). Transcriptomic profiling revealed broad downregulation of meiosis-related genes in lncRNA74687-deficient gonads, with the strongest reduction in mstrg1 expression, indicating a key role of lncRNA74687 in germ-cell meiotic progression. Together, these data show that lncRNA74687 enhances CCNE1 mRNA and the CCNE1 protein in rainbow trout by competitively binding miR-15a-5p. This lncRNA74687–miR-15a-5p–CCNE1 axis regulates gonadal cell proliferation and meiotic gene expression during gonadal development. Full article

Background: Excessive formation of neutrophil extracellular traps (NETs) leads to NETosis, accompanied by the release of citrullinated histone H3 (CitH3), a key mediator of septic inflammation. However, the role of CitH3 in sterile inflammation, such as acute myocardial infarction (MI) and post-MI heart failure, remains incompletely understood. Methods and Results: We investigated the role of CitH3, a byproduct of NETosis, in myocardial ischemia/reperfusion (I/R) injury using a murine MI model. C57BL/6J mice were subjected to left coronary artery (LCA) occlusion followed by reperfusion and treated with either a humanized anti-CitH3 monoclonal antibody (hCitH3-mAb) or control human IgG. In mice undergoing 40 min of LCA occlusion and 24 h of reperfusion, hCitH3-mAb administered 10 min before reperfusion significantly reduced infarct size by 36% compared to control (p < 0.05). Plasma levels of CitH3, IL-1β, and interferon-β were significantly elevated following MI but were attenuated by hCitH3-mAb. In addition, plasma and cardiac tissue from treated mice showed significantly lower levels of citrate synthase, a marker of mitochondrial injury, suggesting that hCitH3-mAb preserved mitochondrial integrity after MI. In mice undergoing 50 min of LCA occlusion and 21 days of reperfusion, longitudinal echocardiography revealed preservation of left ventricular ejection fraction (LVEF) in hCitH3-mAb-treated mice, with significant improvement observed on days 7, 14, and 21 post-MI (p < 0.05 vs. control). hCitH3-mAb also mitigated myocardial fibrosis and preserved tissue architecture. Conclusions: These findings demonstrated CitH3 as a critical mediator of myocardial injury and adverse remodeling following acute MI. Neutralization of CitH3 via hCitH3-mAb attenuates I/R injury and preserves cardiac function by mitigating inflammation and protecting mitochondrial integrity. Targeting CitH3 represents a promising therapeutic strategy to prevent heart failure following MI. Full article

Background: Epigenetic mechanisms and RNA signalling profoundly impact body growth during the early stages of embryonic development. RNA molecules, like microRNAs, play a vital role in early embryonic development, laying the groundwork for future growth and function. miR-124-3p microinjected into mouse fertilised eggs (miR-124-3p*) exhibited a significantly overgrowth phenotype. Behavioural test results showed that miR-124-3p mice were more physically active, as indicated by total distance and movement velocity. However, the molecular mechanism leading to these phenotypic changes mediated by miR-124-3p remains a mystery. This study aimed to investigate the role of epidermal growth factor (EGF) in developing an overgrowth phenotype in miR-124-3p* mice. Results: In this research, we preferred to work with neurospheres (NSs) due to the challenges of handling a single embryo, as NSs exhibit similar features, especially regarding cell growth, differentiation, and capacity for self-renewal. We examined the mRNA expression levels of Sox8, Sox9, Sox10, Doublecortin (Dcx), and Neurod1 genes, which are linked to a tiny phenotype in knockout mice, in total embryos at E7.5 and hippocampal cells isolated from E19.5-day fetus and neurospheres aged 12 and 21 days, which were derived from these hippocampal cells through primary cell culture. These genes are significantly overexpressed in miR-124-3p* NSs, but not in the E7.5 total embryos or the hippocampus of the E19.5 fetus. Conclusions: These findings suggest a possible link between miR-124-3p microinjection and EGF activation, which may be associated with early neurogenesis and neuronal differentiation in embryos. This molecular shift might contribute to the development of mice exhibiting increased physical activity and enlarged body size, although these observations remain correlative and require further validation. Full article

Background: This study investigates the expression of microRNAs (miRNAs) in the semitendinosus muscle of cattle breeds with varying intramuscular fat (IMF) deposition to identify key miRNA regulators of beef marbling, utilizing Hereford (HER; higher IMF) and Holstein-Friesian (HF; moderate IMF) bulls, and Limousin (LIM; low IMF) bulls with lower IMF in the semitendinosus muscle. Methods: MicroRNA profiling used custom bovine microarrays and the Agilent software. The selected miRNAs, miR-34a, miR-149-5p, miR-208b, miR-499, miR-660, and miR-1343-5p, were chosen for validation using real-time PCR, confirming their differential expression. Target prediction utilized miRWalk, while functional and pathway analyses were conducted using the DAVID database to interpret biological relevance. Results: Microarray analysis identified 51 differentially expressed miRNAs. Among these, 24 exhibited consistent expression patterns in high-marbling breeds compared to the low-marbling LIM breed. Bioinformatic analysis of the 4941 predicted target genes of these 24 miRNAs revealed significant enrichment in pathways crucial for marbling, including the adipocytokine, AMPK, MAPK, and PI3K-Akt signaling pathways, as well as biological processes such as cell differentiation and lipid homeostasis. Notably, miR-34a and miR-149-5p emerged as significant regulators, with miR-34a targeting genes like SIRT1, HMGA2, PTPN11, VEGFA, FGF1, FGF2, and BRAF, and miR-149-5p influencing adipogenesis and lipid metabolism through its association with crucial KEGG pathways such as PI3K–Akt, MAPK, PPAR, TGF-β, cAMP, and Wnt signaling, all of which collectively influence adipocyte differentiation, lipid metabolism, cell cycle control, and angiogenesis. Conclusions: The findings underscore identified miRNAs’ possible coordinated regulatory role, particularly miR-34a and miR-149-5p, in the complex molecular mechanisms governing IMF deposition in cattle, providing potential targets for improving beef quality. Full article

Streptococcus suis type 2 (SS2) is a pathogen causing diseases like meningitis and septicaemia worldwide. While microRNAs (miRNAs) are acknowledged for their role in post-transcriptional regulation of gene expression and influence on immune responses, their exact functions in hosts during SS2 infection remain elusive. This study aims to explore the role of miR-7a-5p in macrophages during SS2 infection. Our findings reveal that SS2 infection in J774A.1 cells triggers upregulation of the NLRP3 inflammasome signaling pathways, evidenced by enhanced mRNA expression of pro-inflammatory cytokines (IL-6, IL-18, IL-23, TNF-α) and elevated protein levels of NLRP3, caspase-1, and IL-1β. Concurrently, SS2 infection reduces miR-7a-5p expression. Dual-luciferase reporter assays confirm that miR-7a-5p directly targets the 3′UTR of NLRP3 mRNA. Notably, miR-7a-5p overexpression in SS2-infected J774A.1 cells suppresses NLRP3 inflammasome activation and downstream signaling, as demonstrated by reduced mRNA levels of inflammatory mediators and decreased protein levels of NLRP3, caspase-1, IL-1β, and IL-18. Conversely, miR-7a-5p inhibition produces effects opposite to those of overexpression. In mice, administration of miR-7a-5p mimics mitigates SS2-induced lung, liver, and spleen damage, reducing histological scores in these organs. Collectively, these results show that miR-7a-5p alleviates SS2-induced inflammation by inhibiting the NLRP3 inflammasome, underscoring its potential as a therapeutic target for SS2-associated diseases. Full article

Adipose tissue development plays a critical role in determining carcass quality and meat production efficiency in swine; however, the regulatory mechanisms governing fat deposition remain incompletely understood. Circular RNAs (circRNAs), characterized by high stability and resistance to RNase R degradation, have emerged as important epigenetic regulators of livestock traits. This study investigated the regulatory role of circIDH2 in adipogenic differentiation of porcine preadipocytes and the underlying molecular mechanisms. Functional assays revealed that silencing circIDH2 markedly promoted preadipocyte proliferation while inhibiting differentiation and lipid accumulation; conversely, circIDH2 overexpression produced the opposite effects. Mechanistically, circIDH2 acted as a molecular sponge for miR-193a-5p through complementary base pairing, thereby relieving the repression of its target gene RASGRP4, a positive regulator of adipogenesis. Furthermore, this study demonstrated that miR-193a-5p promoted proliferation but suppressed the differentiation of porcine preadipocytes, whereas RASGRP4 inhibited proliferation while promoting adipogenic differentiation. Rescue experiments further confirmed the regulatory relationship among circIDH2, miR-193a-5p, and RASGRP4. In summary, the findings indicated that circIDH2 functioned as a key regulator of adipogenesis by modulating the miR-193a-5p/RASGRP4 axis, thereby suppressing preadipocyte proliferation and promoting adipogenic differentiation. These results provide a theoretical foundation for future investigations into the regulatory mechanisms of adipose tissue development. Full article

Circulating microRNAs (miRNAs) have emerged as non-invasive biomarkers that may be associated with cancer risk, but their role in the development of colon cancer is still not well understood. We conducted a nested case-control study within the EPIC-Italy cohort to investigate the association between pre-diagnostic serum levels of eight candidate miRNAs (Let7, Mir21, Mir155, Mir181, Mir222, Mir145, Mir92, and Mir20) and subsequent colon cancer occurrence. A total of 104 incident colon cancer cases were matched to 104 controls by center, sex, age, recruitment date, and vital status. miRNA expression was quantified using RT-qPCR and normalized to Mir484. Logistic regression models were applied to estimate odds ratios, 95% confidence intervals, and p-values, adjusting for age at recruitment, smoking status, body mass index, physical activity, adherence to a Mediterranean diet, and socioeconomic position. Elevated expression of Let7 (OR = 0.91; 95% CI: 0.84–1.00; p = 0.04) was associated with slightly lower odds of colon cancer in unadjusted models. Mir21 and Mir222 showed borderline associations (p = 0.07 and p = 0.09, respectively), but these did not remain significant after Bonferroni correction. This result was consistent in the multivariate logistic model: higher levels of Let7 (OR = 0.91; 95% CI: 0.82–1.00; p = 0.06) and Mir222 (OR = 0.75; 95% CI: 0.57–1.00; p = 0.05) are suggestive of an association with lower odds of colon cancer. Our findings highlight the challenges of using circulating miRNAs as very early biomarkers, particularly when samples are collected nearly a decade before diagnosis. Future studies with larger sample sizes, serial blood collections, and integration with inflammatory and immune markers will be crucial to clarify the temporal dynamics of circulating miRNA alterations and their potential role in risk-adapted screening strategies. Full article

Renal urate deposition is a pathological inflammatory condition characterized by the accumulation of urate crystals in the kidneys, resulting from uric acid supersaturation. Cichorium intybus L. (chicory) is a traditional medicinal herb recognized for its efficacy in treating hyperuricemia and gout; however, its effectiveness and underlying mechanisms in mitigating renal urate deposition remain inadequately understood. This study investigates the role of the ATP-binding cassette sub-family G member 2 (ABCG2) transporter and the lncRNA H19/miR-21-3p in renal urate deposition, while also validating the therapeutic effects and mechanisms of chicory extract. Renal urate deposition was induced in rats through the administration of potassium oxonate, adenine, yeast extract, and lipopolysaccharide. The levels of serum uric acid (SUA), urate deposition, inflammation, renal function, and histological changes were analyzed. Dual-luciferase assays, reverse transcription quantitative polymerase chain reaction (RT-qPCR), and immunohistochemistry were utilized to elucidate the relationship among ABCG2, lncRNA H19, and miR-21-3p. The chemical composition and active ingredients of chicory were analyzed using UPLC-LTQ-Orbitrap-MS, along with molecular docking and cell experiments. In rats with renal urate deposition, serum UA levels were elevated, renal UA excretion was reduced, and levels of low inflammatory factors, such as interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and hypersensitivity C-reactive protein (hs-CRP), were increased. Additionally, significant renal tissue damage accompanied the urate deposition. Notably, these abnormalities were substantially reversed following treatment with chicory extract. A dual-luciferase reporter assay confirmed the regulatory relationships among miR-21-3p, lncRNA H19, and ABCG2. Immunohistochemical analysis and RT-qPCR demonstrated a significant upregulation of miR-21-3p expression, alongside a downregulation of lncRNA H19, ABCG2 mRNA, and ABCG2 expression in the kidney tissue of rats with renal urate deposition. Chicory extract may exert its inhibitory effect on renal urate deposition by regulating the lncRNA H19/miR-21-3p axis to enhance ABCG2 expression. Furthermore, UPLC-LTQ-Orbitrap-MS identified 69 components in the chicory extract, including scopoletin, quercetin-3-O-β-D-glucuronide, 11β,13-dihydrolactucopicrin, and kaempferol-3-O-β-D-glucuronide, which were absorbed into the blood of both normal rats and those with renal urate deposition. Molecular docking and cell experiment further validated the effective regulation of 11β,13-dihydrolactucopicrin in ABCG2 and the lncRNA H19/miR-21-3p axis. The downregulation of ABCG2, mediated by the lncRNA H19/miR-21-3p axis, may represent a critical pathogenic mechanism in renal urate deposition. Chicory alleviates this deposition by modulating the lncRNA H19/miR-21-3p axis to enhance ABCG2 expression, potentially through its component, 11β,13-dihydrolactucopicrin, thereby revealing novel therapeutic insights for renal urate deposition. Full article

SLC5A8 is a protein coded by the SLC5A8 gene, and has been proposed as a tumor suppressor and iodide transporter. Its expression is reduced in papillary thyroid carcinoma (PTC), yet the mechanisms underlying this phenomenon are largely unknown. We hypothesized that SLC5A8 expression in PTC is reduced by microRNAs and can be modulated by their inhibition. We used real-time PCR to analyze the expression of SLC5A8 and the microRNAs of interest in a set of 49 PTC/normal tissue pairs. We used an in silico approach to identify microRNAs upregulated in PTC and putatively binding to the SLC5A8 transcript. Luciferase assays were performed to confirm the direct binding of synthetic microRNAs to the 3′UTR of SLC5A8. Subsequently, using mir-expressing plasmids and microRNA sponges, including a microRNA sponge designed to simultaneously inhibit three selected microRNAs, we checked the impact of the modulation of microRNAs on endogenous SLC5A8. Finally, we investigated if modulation of SLC5A8 induces changes in transcriptomes. We confirmed the downregulation of SLC5A8 in PTC. In silico analysis revealed microRNAs potentially targeting SLC5A8. Luciferase assay confirmed direct binding between the 3′UTR of SLC5A8 and miR-181a-5p, miR-182-5p, and miR-494-3p. MiR-181a-5p and miR-182-5p were upregulated in PTC. In HEK293 cell lines, transfection with mir-181a- and mir-182-expressing plasmids decreased endogenous SLC5A8 mRNA, while silencing of miR-181a-5p, miR-182-5p, miR-494-3p, and all three microRNAs simultaneously increased SLC5A8 expression; however, only simultaneous inhibition was able to induce changes visible for SLC5A8 protein. Changes in SLC5A8 expression did not alter the whole transcriptome significantly. This study shows microRNA-dependent regulation of SLC5A8 expression and underlines the potential effectiveness of simultaneous inhibition of a few microRNAs to derepress their common target. Full article

Background: Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of urothelial carcinoma (UC); however, their efficacy varies among patients. Identifying reliable biomarkers to predict response to ICIs remains challenging. We aimed to explore urinary microRNAs (miRNAs) as potential biomarkers for predicting ICI efficacy in patients with UC. Methods: We prospectively collected urinary samples from patients with UC before ICI initiation and investigated the predictive value of urinary miRNAs in patients with UC receiving ICIs. The expression levels of these miRNAs in pretreated urine samples were analyzed using next-generation sequencing. The patients were categorized as responders (those with stable disease or better for >6 months) or nonresponders (those who experienced disease progression within 6 months of treatment initiation). Urinary miRNA levels were compared between the groups to assess their potential as predictive biomarkers. Results: Elevated expression of miR-185-5p and miR-425-5p in the responder group was significantly associated with improved overall and progression-free survival in patients with bladder cancer treated with ICIs (p < 0.05). Conversely, higher levels of miR-30a-5p and miR-542-3p in the nonresponder group were correlated with a poorer response to ICIs, suggesting a potential role in immune resistance. Conclusions: miR-185-5p and miR-425-5p can serve as predictive biomarkers of favorable ICI efficacy in bladder cancer, whereas miR-30a-5p and miR-542-3p could be associated with resistance mechanisms. These findings highlight the potential of miRNA-based biomarkers, particularly those found in urine samples, to guide personalized immunotherapeutic strategies for UC treatment. Full article

Background/Objectives: Colorectal cancer (CRC) is one of the most common malignancies worldwide. microRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression post-transcriptionally and have emerged as important regulators in cancer biology. This study aimed to investigate the roles of miR-379-5p and miR-519a-3p in CRC using Quantitative Real-Time PCR (RT-qPCR) and comprehensive bioinformatic analyses. Methods: Tumor tissues and matched adjacent normal tissues were collected from 54 patients with CRC. The expression levels of miR-379-5p and miR-519a-3p in these tissues were determined using the RT-qPCR method. To investigate the functional roles of differently expressed miRNAs, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to construct miRNA–transcription factor (TF)–target gene–disease interaction networks. Results: It was found that the expression level of miR-379-5p was statistically significantly increased in tumor tissues compared to normal tissues, while miR-519a-3p was decreased (p < 0.05). GO analysis revealed enrichment in several important biological processes, including cellular protein metabolic processes, biosynthetic processes, response to stress, and nucleic acid binding TF activity. KEGG analysis exhibited that dysregulated miRNAs were associated with important pathways related to carcinogenesis, such as p53 signaling, TGF-beta signaling, and FoxO signaling pathways. Additionally, the miRNAs-TFs-Genes-Diseases Networks analysis identified ESR1 and FOXA1 as common target TFs of dysregulated miRNAs. Network analyses showed that dysregulated miRNAs interact with CRC-associated genes (Caspase 3 (CASP3), Adenomatous polyposis coli (APC), and AKT serine/threonine kinase 3 (AKT3)). Conclusions: The present study indicates that miR-379-5p and miR-519a-3p may be involved in CRC progression, with miR-379-5p being upregulated and miR-519a-3p being downregulated in tumor tissues. However, further functional studies are required to clarify their potential roles in tumor biology. The findings of the study suggest that miR-379-5p and miR-519a-3p may be associated with regulatory pathways related to CRC. These miRNAs have the potential to serve as diagnostic biomarkers or therapeutic targets in CRC. Full article

Astrocytic tumors are a heterogeneous group of glial neoplasms characterized by marked differences in biological behavior and patient prognosis. Transforming growth factor-beta (TGF-β) signaling plays a pivotal role in astrocytoma pathogenesis; however, the extent and mechanisms of its epigenetic regulation remain poorly understood. This study aimed to investigate how promoter methylation and microRNA-mediated mechanisms regulate key genes within the TGF-β signaling pathway across various astrocytoma grades. Tumor tissue samples from 65 patients with WHO grade II–IV astrocytomas were analyzed using Affymetrix gene expression and microRNA microarrays. Promoter methylation of TGF-β signaling genes was assessed using methylation-specific polymerase chain reaction (MSP). Gene expression was validated by reverse transcription quantitative polymerase chain reaction (RT-qPCR), and protein levels were quantified using enzyme-linked immunosorbent assay (ELISA). MicroRNA targets were predicted using bioinformatic tools, and survival analyses were conducted using Kaplan–Meier and Cox regression models. Six genes—SMAD1, SMAD3, SKIL, BMP2, SMAD4, and MAPK1—showed significant upregulation in high-grade tumors (fold change > 5.0, p < 0.05), supported by RT-qPCR and protein-level data. Promoter hypomethylation and reduced expression of regulatory microRNAs (e.g., hsa-miR-145-5p targeting SMAD3) were more common in higher-grade tumors. Protein–protein interaction analysis indicated strong functional interconnectivity among the overexpressed genes. High protein levels of SMAD1, SMAD3, and SKIL were significantly associated with shorter overall survival (p < 0.001). This multi-level analysis reveals that astrocytic tumor progression involves epigenetic derepression and microRNA-mediated dysregulation of TGF-β signaling. Elevated expression of SMAD1, SMAD3, and SKIL emerged as strong prognostic indicators, underscoring their potential as biomarkers and therapeutic targets in astrocytic tumors. Full article