Protein phosphorylation is the most common type of posttranslationalmodification and can affect various cellular activities (34). Moststudies of protein phosphorylation mainly focused on kinases, actuallyphosphatases can also be used as regulatory targets. PP2A is the mostimportant serine/threonine protein phosphatase that regulates thedephosphorylation of most phosphorylated serine and phosphorylatedthreonine in the body, and plays an important role in the activity ofplentiful tumor-related proteins (35). Our study confirmed that PDHPS1 can bind to PTPA, the activator of PP2A, and affect thephosphorylation level of YAP, an important regulator of tumor. Theregulatory effect of PDHPS1 on the phosphorylation level of YAPconfirms the important role of phosphatase in the regulation ofphosphorylated proteins, and meanwhile suggests that PDHPS1 mayalso have a potential therapeutic effect in other YAP-related tumors.