Knockdown of thymidylate synthase (TS) induces programmed death-ligand 1 (PD-L1) expression in non-small-cell lung cancer (NSCLC) cells and decreases the production of interleukin-2 (IL-2) by activated T cells in the NSCLC and T cell coculture system. (A–D), CL1-5 or CL141 cells transfected with control-siRNA (siCtrl) or TS -siRNA (siTS) oligonucleotides were lysed and analyzed by qRT-PCR (A), flow cytometry (B), or immunoblotting (C, D) 72 hours after transfection. Data are shown as means and SD for three independent experiments (n=3). (E, F) CL1-5 or CL141 cells transfected with control-siRNA (siCtrl), TS-siRNA (siTS) and RelA-siRNA (siRelA) oligonucleotides in different combination were lysed and analyzed by qRT-PCR (E) or immunoblotting (F), 72 hours after transfection. (G, H) CL1-5 or CL141 cells were transfected with siCtrl or siTS siRNA oligonucleotides for 24 hours and followed by cocultured with Jurkat T-cells or PBMCs at different cancer to T cell ratios in the presence of the 1×T cell stimulation cocktail for additional 48 hours. (G) IL-2 levels were measured by ELISA. (H) The levels of CD69 and intracellular IL-2 produced by Jurkat T-cells or PBMCs were measured by flow cytometry. **P
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