STAT3 and hepatocellular carcinoma: In addition, due to the scarcity of quantitative data on kinetics rates and initial conditions of IL-6 induced STAT3, Akt, and ERK activation in endothelial cells, we used parameters that govern IL-6 induced STAT3 pathway in human hepatoma cells52 and VEGF- and FGF-induced Akt and ERK pathways in endothelial cells70 as our initial guess to tune the parameters for IL-6 induced endothelial signaling, although the model was calibrated and validated using HUVEC data44.