Increasing evidence suggests that ion channels not only regulate electric signaling in excitable cells but also play important roles in the development of human cancer. However, the roles of ion channels in glioma remain controversial. We systematically analyzed the expression patterns of ion channel genes in a cohort of Chinese patients with glioma using whole-genome mRNA expression profiling. First, a molecular signature comprising 47 ion channel genes (IC47) was identified using Spearman's rank correlation test conducted between tumor grade and gene expression. We assigned a risk score based on IC47 to each glioma patient. We demonstrated that the risk score effectively predicted overall survival in glioma patients. Next, we screened IC47 in different molecular glioma subtypes. IC47 showed a Mesenchymal subtype and wild-type IDH1 preference. Gene ontology (GO) analysis and gene set variation analysis (GSVA) for the functional annotation of IC47 showed that patients with high-risk scores tended to exhibit the decreased expression of proteins associated with the apoptosis and cell adhesion, and higher expression of proteins associated with the cell cycle and cell proliferation. These results suggest that ion channel gene expression could improve the subtype classification in gliomas at the molecular level. The findings in the present study have been validated in two independent cohorts.
Keywords: Glioma; IDH1 mutation; Ion channel genes; Risk score; Whole-genome mRNA expression.