The pathogenesis of NSCLC is very intricate, involving the abnormal transduction of many signaling pathways, including WNT, tyrosine kinase, Notch, EGFR, Hedgehog, etc. EGFR, which promotes malignant proliferation, metastasis, and angiogenesis of cancer cells by activating intracellular RAS/RAF/MEK/MAPK, PI3K/PTEN/AKT and STAT3 signaling pathways, and inhibits apoptosis of cancer cells, is expressed in over 60% of lung cancer and regarded as an important target for prognosis evaluation and treatment of NSCLC [11]. The gene discussed is STAT3; the disease is cancer.