In vitro, r-irisin inhibited the proliferation, migration, invasion, and epithelial-to-mesenchymal transition (EMT) in lung cancer (11), epithelial ovarian cancer (107), and pancreatic cancer (PC) (108) cells by inhibiting PI3K/Akt- and Signal transducer and activator of transcription 3 (STAT3)-mediated (109) downstream Snail expression (an important role in stimulating EMT). This evidence concerns the gene STAT3 and lung cancer.