The results of OS and DSS analysis showed that high KCNH2 gene expression was associated with a poor prognosis in three tumour types [GBM (HR 1.20 in OS, HR 1.27 in DSS), LIHC (HR 1.34 in OS, HR 1.26 in DSS), and THCA (HR 1.90 in OS, HR 2.41 in DSS)], while low expression was associated with a poor prognosis in 2 tumour types [PAAD (HR 0.72 in OS, HR 0.70 in DSS) and ACC (HR 0.76 in OS, HR 0.78 in DSS)] (Additional file 1: Fig. S1). This evidence concerns the gene KCNH2 and glioblastoma.