PDCD1 and lung cancer: Consistently, the results of qPCR (Fig 1B) and Western blot (Fig 1C) revealed that, compared to normal lung fibroblast MRC-5, the NSCLC and SCLC cancer cell lines, H1975, A549, H1650, H460, H69 and H82, had higher expression of PD1 and PD-L1, in agreement with previous findings that PD1 and PD-L1 are upregulated in lung cancer cells [25–27].