We also found that there was a positive correlation between the expressions of GRP75 and XIAP in HCC tissues, and that, knockdown of GRP75 decreased the phosphorylation of XIAP at Ser87 site (a classical phosphorylation site, enhancing the stability of XIAP) and its mRNA levels in both HepG2B[a]P and HuH7B[a]P cells (Fig. 5C and Supplementary Fig. S10). Here, XIAP is linked to hepatocellular carcinoma.