MAPK3 and hepatocellular carcinoma: To suppress the tumorigenic phenotypes of HCC cells, SPINK6 has to be secreted into extracellular space, where it likely triggers regulation of signaling pathways, affecting at least an intracellular signaling molecules, ERK1/2, the regulated activity of which probably further suppresses a series of intracellular and extracellular factors implicated in tumorigenesis.