STAT3 and lung carcinoma: Ota et al. showed that an MEK inhibitor (U0126) and a PI3K inhibitor (LY294002), but not a STAT3 inhibitor (S3I–201), decrease PD-L1 expression in EGFR-mutant and EML4-ALK-positive lung cancer cells, as determined by qRT-PCR and flow cytometry [13].