CD274 and breast cancer: As shown in Fig. 2B, the 5T4 expression was detectable at sufficient (reliable absorbance values ≥ 0.1) levels on the surface of A-549, MDA-MB-231, and Li-7 cell lines derived from lung, breast cancer, and hepatocellular carcinoma, respectively, whereas PD-L1 was expressed at higher levels on A-549 and MDA-MB-231 than Li-7 cells.