To correlate the observations obtained in HCC patients with those obtained in HepG2, we studied the subcellular localization of IRS-4 in HepG2 cells using immunofluorescence microscopy in basal conditions (in absence of FBS during 72 h) and after incubation with IGF-1 (25 nM) or with EGF (20 ng/mL) for 30 min (Figure 5E). Here, IRS4 is linked to hepatocellular carcinoma.