Recently, it has been reported that TIPRL is overexpressed in hepatocellular carcinoma, and that knockdown of TIPRL by small interfering RNA causes sustained activation of MKK7 (mitogen-activated protein kinase kinase 7) and JNK (c-Jun N-terminal kinase) by increasing MKK7 phosphorylation (12). Here, MAPK8 is linked to hepatocellular carcinoma.