Fig. 5.

Circ-HSP90A riggers CD8⁺ T cells apoptosis through PD-1/PD-L1 immune checkpoint. A, B CD8⁺ T cells were co-cultured with two NSCLC cells with circ-HSP90A down-regulation. Flow cytometry analysis assessed CD8⁺ T cell percentage and apoptosis. C, D RT-qPCR and western blot detected PD-L1 mRNA and protein levels in two NSCLC cells with circ-HSP90A silence. E, F RT-qPCR and western blot verified the elevation efficiency of PD-L1 in two NSCLC cells. G, H CD8⁺ T cells were co-cultured with two NSCLC cells and then transfected with sh-NC, sh-circ-HSP90A#1, and sh-circ-HSP90A#1 + pcDNA3.1/PD-L1. Flow cytometry analysis assessed CD8⁺ T cell percentage and apoptosis. **P < 0.01