To this end, we carried out quantitative PCR (qPCR) for mRNA from fresh-frozen non-small cell lung cancer (NSCLC) patient tissues and found that the levels of both PD1 and PD-L1 are higher in fresh-frozen patient tumors compared to the normal adjacent tissues (n = 30) (Fig 1A). This evidence concerns the gene CD274 and non-small cell lung carcinoma.