To gain insight into the lymphocyte functional response, we analyzed the expression of checkpoint molecules PD-1 and LAG-3 on CD3+ T cells in the two areas of GBM specimens, both at diagnosis and at relapse, and observed a steady high frequency of T cells expressing PD-1 in both cases, but a lower expression of LAG-3 on T cells in relapsing tumors (Figure 3A,B). Here, LAG3 is linked to glioblastoma.