IGFBP2 from a novel copper metabolism-associated biomarker promoted glioma progression and response to immunotherapy.

Introduction: Copper metabolism encompasses all cellular metabolic processes involving copper ions and plays a significant role in the pathogenesis of diseases, including cancer. Furthermore, copper is intricately involved in various processes related to nucleotide metabolism. However, a comprehensive analysis of copper metabolism in gliomas remains lacking despite its importance. Methods: To address this gap, glioma patients were stratified based on the expression levels of copper metabolism-related genes. By utilizing machine learning techniques, a novel copper metabolism-associated biomarker was developed. The potential of this biomarker in prognosis, mutation analysis, and predicting immunotherapy response efficiency in gliomas was systematically investigated. Results: Notably, IGFBP2, identified as a glioma tumor promoter, was found to promote disease progression and influence immunotherapy response. Additionally, glioma-derived IGFBP2 was observed to enhance microglial migration. High IGFBP2 expression in GBM cells facilitated macrophage interactions through the EGFR, CD63, ITGB1, and CD44 signaling pathways. Discussion: Overall, the copper metabolism-associated biomarker shows promising potential to enhance the clinical management of gliomas, offering valuable insights into disease prognosis and treatment strategies.

GPX8 regulates pan-apoptosis in gliomas to promote microglial migration and mediate immunotherapy responses.

Introduction: Gliomas have emerged as the predominant brain tumor type in recent decades, yet the exploration of non-apoptotic cell death regulated by the pan-optosome complex, known as pan-apoptosis, remains largely unexplored in this context. This study aims to illuminate the molecular properties of pan-apoptosis-related genes in glioma patients, classifying them and developing a signature using machine learning techniques. Methods: The prognostic significance, mutation features, immunological characteristics, and pharmaceutical prediction performance of this signature were comprehensively investigated. Furthermore, GPX8, a gene of interest, was extensively examined for its prognostic value, immunological characteristics, medication prediction performance, and immunotherapy prediction potential. Results: Experimental techniques such as CCK-8, Transwell, and EdU investigations revealed that GPX8 acts as a tumor accelerator in gliomas. At the single-cell RNA sequencing level, GPX8 appeared to facilitate cell contact between tumor cells and macrophages, potentially enhancing microglial migration. Conclusions: The incorporation of pan-apoptosis-related features shows promising potential for clinical applications in predicting tumor progression and advancing immunotherapeutic strategies. However, further in vitro and in vivo investigations are necessary to validate the tumorigenic and immunogenic processes associated with GPX8 in gliomas.

Integrating machine learning and bioinformatics analysis to m6A regulator-mediated methylation modification models for predicting glioblastoma patients' prognosis and immunotherapy response.

BACKGROUND: Epigenetic regulations of immune responses are essential for cancer development and growth. As a critical step, comprehensive and rigorous explorations of m6A methylation are important to determine its prognostic significance, tumor microenvironment (TME) infiltration characteristics and underlying relationship with glioblastoma (GBM). METHODS: To evaluate m6A modification patterns in GBM, we conducted unsupervised clustering to determine the expression levels of GBM-related m6A regulatory factors and performed differential analysis to obtain m6A-related genes. Consistent clustering was used to generate m6A regulators cluster A and B. Machine learning algorithms were implemented for identifying TME features and predicting the response of GBM patients receiving immunotherapy. RESULTS: It is found that the m6A regulatory factor significantly regulates the mutation of GBM and TME. Based on Europe, America, and China data, we established m6Ascore through the m6A model. The model accurately predicted the results of 1206 GBM patients from the discovery cohort. Additionally, a high m6A score was associated with poor prognoses. Significant TME features were found among the different m6A score groups, which demonstrated positive correlations with biological functions (i.e., EMT2) and immune checkpoints. CONCLUSIONS: m6A modification was important to characterize the tumorigenesis and TME infiltration in GBM. The m6Ascore provided GBM patients with valuable and accurate prognosis and prediction of clinical response to various treatment modalities, which could be useful to guide patient treatments.

circ_PTN contributes to -cisplatin resistance in glioblastoma via PI3K/AKT signaling through the miR-542-3p/PIK3R3 pathway.

Glioblastoma has been identified as the most common and aggressive primary brain tumor in adults. Recently, it has been found that cisplatin (DDP) treatment is a common chemotherapeutic method for GBM patients. circ_PTN (ID number: hsa_circ_0003949) is a newly found circular (circRNA) which has been proved to be highly expressed in GBM cells, while its role in GBM remains unclear. Therefore, our study focused on investigating the role of circ_PTN in the DDP resistance of GBM cells. The expression of circ_PTN in DDP-sensitive and DDP-resistant GBM cells was detected in our assay. Functional experiments were utilized to unveil the effects of circ_PTN on the DDP resistance of GBM cells. Moreover, mechanism assays were conducted to confirm the mechanism of how circ_PTN affected the DDP resistance of GBM cells. According to the results, we found that circ_PTN promoted the DDP resistance of GBM cells through activation of the PI3K/AKT pathway. Moreover, circ_PTN silencing inhibited the DDP resistance of GBM tumors in vivo. To conclude, our study unveiled the influence of circ_PTN on the DDP resistance of GBM cells, which might provide a therapeutic target for GBM treatment via DDP.

[Curcumin suppresses invasiveness and migration of human glioma cells in vitro by inhibiting HDGF/ß-catenin complex].

OBJECTIVE: To investigate the effect of curcumin on the invasion and migration of human glioma cells in vitro and explore the molecular mechanisms. METHODS: MTT assay was used for screening the optimal curcumin concentrations. The effects of curcumin on the invasion and metastasis of human glioma cell lines U251 and LN229 were tested using Transwell assay, Boyden assay and wound-healing assays. The expression of the related proteins and their interactions were determined using Western blotting and coimmunoprecipitation assay. RESULTS: Curcumin at the concentration of 20 µmol/L for 48 h was used as the optimal condition for subsequent cell treatment. In the two glioma cell lines, curcumin significantly suppressed the invasion and migration of the cells (P < 0.05) and lowered the expressions of hepatoma-derived growth factor (HDGF), Ncadherin, vimentin, Snail and Slug, but increased the expression of E-cadherin. Interference of HDGF in curcumin-treated glioma cells synergistically inhibited the epithelial-mesenchymal transition (EMT) signals, while overexpression of HDGF significantly reversed the inhibitory effect of curcumin on EMT; curcumin treatment could significantly reduce the binding of HDGF to ß-catenin. CONCLUSIONS: Curcumin suppresses EMT signal by reducing HDGF/ß-catenin complex and thereby lowers the migration and invasion abilities of human glioma cells in vitro.

The expression of MMP19 and its clinical significance in glioma.

AIMS: The expression of phosphoglycerate kinase 1 (MMP19) is elevated in some cancers. However, the clinical features and prognostic value of glioma patients with MMP19 expression are unclear. In this study, the expression level of MMP19 and the correlation between the level of MMP19 expression and the clinicopathologic data in glioma patients including survival were examined. METHODS AND RESULTS: Using real-time PCR, the mRNA expression of MMP19 was examined in 61 fresh glioma tissues and 32 brain samples. The result indicated that MMP19 mRNA was obviously elevated in glioma tissues compared to brain tissues. Further, we observed that MMP19 mRNA was much higher in stage III patients than it was in stage I-II patients. The expression of the MMP19 protein was determined by immunohistochemical analysis in 156 paraffin-embedded glioma samples and 35 normal paraffin-embedded brain samples. The MMP19 protein level was significantly increased in glioma tissues compared to brain tissues (P = 0.008). Furthermore, we observed that a high expression of MMP19 protein was positively associated with clinical stage (P = 0.008) but did not correlate with age, gender, or histological type. An increased MMP19 protein expression was associated with poor overall survival rates (P = 0.001). A stratified analysis showed that patients with high MMP19 protein expression indicated a worse prognosis occurring in WHO III-IV stages (P = 0.001). A Multivariate analysis indicated that a high expression of the MMP19 protein was an independent prognostic indicator of patient survival (P = 0.009). CONCLUSIONS: MMP19 is overexpressed and plays a significant role in disease progression and poor outcome in glioma patients.