HMGB1 and glioblastoma: These correlations were also observed in the subgroup of GBM patients; the negative correlation of HMGB1 with the percentage of CD14+ TREM-1+ cells had a P value of 0.016 and for negative correlation of HMGB1 with the TREM-1/TREM-2 ratio, the P value was 0.008 (Table 2, Figure 8).