For example, upon treatment of hepatoma cells and primary human macrophages with IL-6-type cytokines (e.g. IL-6 or OncostatinM) STAT1 phosphorylation can be observed but most of the phosphorylated STAT1 is rather trapped in STAT1/STAT3 heterodimeric complexes [10]. Here, STAT1 is linked to hepatocellular carcinoma.