ObjectiveTo establish the diagnostic model of glioblastoma multiforme (GBM) based on random forest algorithm and artificial neural network (ANN). MethodsThe datasets of GSE4290 and GSE50161 from the GEO database were downloaded as training set, and the datasets of GSE66354, GSE11650, and GSE15824 were downloaded as validation set. Differentially expressed genes (DEGs) were screened from GBM brain tissues samples and normal brain tissues samples in the training set by employing the R language 4.2.1 software. The Metascape online tool was used for cluster analysis on DEGs, and the R language 4.2.1 software was employed to perform Gene Ontology (GO) functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis on DEGs. Key genes were screened by the random forest algorithm based on DEGs, and then the ANN model for diagnosing GBM was established through the key genes. The receiver operating characteristic (ROC) curve was drawn, and internal and external validation on ANN model were performed by using the training set and the validation set, respectively. ResultsA total of 461 DEGs were screened. The results of cluster analysis revealed that DEGs were mainly enriched in trans-synaptic signaling, neuronal system, and regulation of chemical synaptic transmission, etc.; in addition, the results of GO functional enrichment analysis indicated that DEGs were mainly involved in biological processes including the regulation of trans-synaptic signaling and transport of neurotransmitters, etc., involved in cellular compositions mainly including glutamatergic synapses and ion channel complexes, etc., and mainly involved in molecular functions containing γ-aminobutyric acid (GABA)-A receptor activity and GABA-gated chloride channel activity, etc. The results of KEGG pathway enrichment analysis interpreted that DEGs were mainly enriched in signaling pathways in terms of regulating chemical synaptic transmission, regulating trans-synaptic signaling, and transporting neurotransmitters. A total of 6 key genes were screened, namely KIAA0101, DnaJ (Hsp40) homolog subfamily C member 6 (DNAJC6), coagulation factor Ⅱ thrombin receptor (F2R), leucine rich repeat and immunoglobulin domain containing 2 (LINGO2), minichromosome maintenance complex component (MCM)2, and corticotropin-releasing hormone (CRH). Areas under the curve of ANN model established based on aforementioned 6 key genes for diagnosing GBM were 0.952-1.000. ConclusionThere are six key DEGs related to GBM, namely KIAA0101, DNAJC6, F2R, LINGO2, MCM2, and CRH, respectively, and the ANN model established based on these genes for GBM exerts relatively high diagnostic efficiency.