Since the increased volume of hepatoma in Atg7ΔHepFgf21−/− mice compared to Atg7ΔHepFgf21+/+ mice suggested increased proliferation of autophagy-deficient tumor due to the absence of FGF21, we next studied whether the proliferation of autophagy-deficient tumor in Atg7ΔHep mice was affected by FGF21. The gene discussed is FGF21; the disease is hepatocellular carcinoma.