TAT-PDHPS1 is a peptide inhibitor targeting Yes-associated protein (YAP) signaling, composed of the endogenous peptide PDHPS1 and the cell-penetrating peptide sequence TAT. It operates by binding to protein phosphatase 2 phosphatase activator (PTPA), thereby activating protein phosphatase 2A (PP2A). This activation precipitates the phosphorylation of YAP, culminating in the suppression of genes targeted by YAP. Demonstrated to inhibit the proliferation of ovarian cancer cells in vitro and reduce ovarian tumor growth in a subcutaneous xenograft mouse model, TAT-PDHPS1 presents a potent approach to managing ovarian malignancies.