Figure 4b shows that among all groups, the average PLCβ1 signal strengths were the highest in the nontumor controls (n = 23), followed by the grade II (n = 7), grade III (n = 19), and grade IV (n = 81) astrocytoma groups (Fig. 4b). This evidence concerns the gene PLCB1 and astrocytoma (excluding glioblastoma).