To test whether PAPPA might be indeed responsible for activation and auto-regulation of the NFκB pathway, we assessed NFκB activity in stimulated HCC cells and observed a striking correlation of PAPPA levels in conditioned medium (CM) from the 15 different HSCs with NFκB activity induced in HCC cells upon incubation with these different CMs (Fig 5A). Here, PAPPA is linked to hepatocellular carcinoma.