WBP-2, a putative ligand that binds to the WW-domain of Yes kinase-associated protein 1(YAP1) with relatively high affinity and specificity through PPXY motifs, acts as a coactivator of gene transcription regulation (e.g., estrogen receptor (ER)/ progesterone receptor (PR) transactivation pathway) and it may play important roles in diverse pathological conditions, such as cancer, inherited genetic diseases, and inflammation (Chan et al., 2011; Chen et al., 2017). This evidence concerns the gene PGR and cancer.