Previous studies showed that leptin promoted viability and metastasis of renal cell carcinoma cells via activating the ERK1/2 and JAK/STAT3 signaling which could be partially abolished by ERK phosphorylation inhibitor U0126 and STAT3 phosphorylation inhibitor AG490, respectively (Li et al., 2008). The gene discussed is MAPK3; the disease is renal cell carcinoma.