ERBB4 and central nervous system cancer: Interestingly, a Kaplan-Meier survival curve demonstrates statistical significance among the stratified groups based on PLCβ1 expression in glioma and its subclass astrocytoma, while a Kaplan-Meier survival curve based on different ERBB4 expression levels only shows statistical significance among stratified glioma cases, but fails to show statistical significance among astrocytoma cases (Supplement S4).