Among the available PP2A regulatory subunits in hand, we identified that the B55β subunit remarkably reduced the level of p‐XPO5 in both HEK‐293T and HCC cell lines (Figure 2A and B), and further confirmed the involvement of B55β in XPO5 dephosphorylation via immunoprecipitation of XPO5 upon B55 augmentation and examination of the phosphorylated status of the recovered protein (Figure 2C). This evidence concerns the gene PTPA and hepatocellular carcinoma.