GBM is an aggressive primary intracranial malignant tumor, accounting for approximately 14.5% and 48.6% of all tumors and malignant tumors, respectively.10 It is generally associated with a high rate of recurrence, significant mortality, and poor clinical prognosis.11 Existing chemotherapeutic agents, including temozolomide, exhibit limited therapeutic potential and drug resistance is often encountered in clinical practice. Despite the development of various treatment options, overall outcomes have remained unsatisfactory. Thus, identifying novel target genes affecting the prognosis of GBM and understanding their molecular mechanisms are essential for improving clinical outcomes. Traditional Chinese medicine has shown efficacy in preventing and treating GBM, with advantages mainly in alleviating toxic side effects, enhancing the effects of radiotherapy and chemotherapy, improving quality of life, reducing recurrence rates, and extending patient survival.
In this study, we used network pharmacology and bioinformatic analyses to identify reliable target genes for GBM. Initially, BCA targets were identified using online pharmacology databases. Subsequently, genes expressed in GBM were screened from the DisGeNet, GeneCards, and TTD databases. DEGs for GBM were sourced from GEPIA and analyzed using VolcaNoseR. By integrating data from drug, disease, and DEG interaction networks, we identified 63 crossover target genes for GBM treatment. PPI network analysis revealed four key target genes—AKT1, EGFR, CASP3, and MMP9— as highly relevant to treatment. These genes are associated with the occurrence, development, and prognosis of GBM. GO enrichment analysis showed that these targets are involved in processes, such as cell migration, proliferation, apoptosis, and other multicellular biological processes pertinent to GBM's onset and progression. In the MF category, the genes were associated with protein binding and protein serine/ /tyrosine/ threonine kinase activity. KEGG pathway enrichment analysis revealed that these genes were mainly involved in the PI3K-Akt and MAPK signalling pathways. Additionally, molecular docking analysis confirmed the feasibility of the binding modes, demonstrating that BCA had a high affinity for these four key target genes.
Subsequently, we conducted a comprehensive and integrated bioinformatics analysis to discern the biological functions and potential regulatory pathways of hub genes in GBM. We aimed to assess the expression and prognostic value of AKT1, EGFR, CASP3, and MMP9 in GBM. We found that these hub genes were notably upregulated in GBM samples and correlated with tumor grade, and that high expression levels were closely linked to poor overall survival and disease-free survival in patients with GBM. Additionally, we observed that the expression of AKT1 was positively correlated with that of EGFR, CASP3, and MMP9. These results strongly manifest that these four genes are significantly related to prognosis and could serve as hub genes in the BCA treatment of GBM.
AKT1 is a serine/threonine protein kinase that modulates protein synthesis and transcription. While the expression of AKT1 in the GBM group was not more than twice as high as that in the control group, the difference between the two groups was still statistically significant. Growing evidence indicates that AKT1 plays a key role in the progression and aggressiveness of GBM. It is a key protein involved in processes, such as cell proliferation, apoptosis, and migration. In various types of cancer, including GBM, elevated AKT1 expression has been observed during disease progression. Consequently, AKT1 is viewed as a critical factor in tumor advancement.12 It has been confirmed that inhibiting the Akt/mTOR signalling pathway triggers both autophagy and apoptosis in glioma cells.13
EGFR is a transmembrane glycoprotein and a member of the ErbB family of receptor tyrosine kinases. It is overexpressed and mutated in GBM as well as in many other types of cancers, where it promotes GBM proliferation, invasion, and drug resistance.14 EGFR serves as a promising candidate target in advanced precision medicine for patients with central nervous system tumors.15 Zhou's research has shown that inhibiting the EGFR/SRC/STAT3 signalling pathway suppresses cell proliferation, induces apoptosis, and block cell cycle in the G2/M phase of gliomas.16
CASP3 is renowned for being activated during apoptosis upon cellular exposure to drugs and radiotherapy and is often considered a marker of cancer treatment efficacy.17 Recent studies have revealed that CASP3 also plays non-apoptotic roles, such as promoting tumor migration, invasion, and relapse. CASP3 interacts with DNA and stimulates angiogenesis by inducing the expression of proangiogenic genes and activating pathways that promote endothelial cell activation, tumor recurrence, and chemotherapy resistance.18 Tumor cells with CASP3 knockout are highly sensitive to radiotherapy and chemotherapy due to inhibited epithelial-mesenchymal transition.19
MMP9 was notably overexpressed among the DEGs in GBM according to the TCGA database. MMP9 plays a critical role in degrading the extracellular matrix and is instrumental in promoting tumor tissue invasion and metastasis.20 Elevated MMP9 levels are positively correlated with GBM cancer progression, and high levels in brain tumor tissues indicate a poor prognosis.21 It has been established that blue light-activated curcumin induces apoptosis in GBM through ROS-dependent downregulation of MMP pathways.22
In this study, we explored the potential correlation between immune regulation and hub genes and found that tumor-infiltrating immune cells play a significant role in molecular mechanisms related to prognosis, thereby promoting tumor progression and therapeutic resistance. We speculate that targeting these four newly identified genes could influence the immune microenvironment of GBM.