Since IL-6, through JAK/STAT3 signaling, might be involved in EMT in lung adenocarcinoma, and metformin can inhibit EMT and STAT3 phosphorylation in other cancer types, we hypothesized that metformin might be able to inhibit IL-6-induced EMT and growth and metastasis in lung adenocarcinoma. The gene discussed is STAT3; the disease is cancer.