Figure 1. Investigations on the PD-L1 and NKG2D ligand levels in lung cancer cells after radiation treatment.

(A) qPCR analyses of PD-L1 mRNA expressions in A549 and H157 cells after radiation; at various time points (upper panel) and various radiation doses (lower panel). Total mRNAs were extracted from non-radiated and radiated cells, cDNA converted, and expressions of PD-L1 were analyzed. (B) qPCR analyses of PD-L1 levels after treated radiation with 6, 12, and 18 Gy (accumulated) radiation. A549 and H157 cells were treated with radiation (6 Gy) and the survived cells after radiation were further treated with more radiation (6 Gy, one week interval to a total of 12 Gy or 18 Gy), qPCR analyses were performed similarly. (C) qPCR analyses of five NKG2D ligands, ULBP1, ULBP2, ULBP3, MICA, and MICB in irradiated and non-irradiated A549 and H157 cells. *p < 0.05, **p < 0.01, ***p < 0.001