Another approach to boost the activity of CD19-specific CAR-T cells against B-cell lymphoma cells with enhanced resistance to CAR-T-cell cytotoxicity relies on the selective cyclooxygenase (COX)-2 inhibitor celecoxib (Figure 2), which could substantially restore the cytotoxicity of CAR-T cells to lymphoma cells by partially reversing the resistance to TRAIL-mediated apoptosis [36]. Here, CD19 is linked to lymphoma.