Patients with high PAK1 and PAK2 expression had significantly shorter median RFS than those with low PAK1 and PAK2 expression...The PAK inhibitors PF and FRAX597 demonstrated strong anti-tumor activity in vitro (Table 2). Both inhibitors suppressed cell proliferation in a time- and dose-dependent manner (Figure 5)....PAK1 and PAK2 play certain roles in the occurrence and recurrence of T-LBL, and their potential as novel biomarkers deserves further exploring. Our results underscore the potential of PAK inhibitor as effective target therapy for T-LBL.