MAPK9 and hepatocellular carcinoma: First, we determined whether or not JNK is activated in the liver of 2-year-old HBV transgenic mice, which developed HCC, and non-transgenic control mice by analyzing the levels of JNK1, JNK2 and their activated forms (i.e., p-JNK1 and p-JNK2) by Western blot (Fig. 1A).