Zhang et al show that serine protease 50 (TSP50) binds to glucose‐6‐phosphate dehydrogenase (G6PD) and inhibits its acetylation at the K171 site in the cytoplasm of hepatocellular carcinoma (HCC) cells, by which TSP50 enhances lipid synthesis and promotes cell proliferation. The gene discussed is PRSS50; the disease is hepatocellular carcinoma.