YAP1 and pancreatic ductal adenocarcinoma: In human monocytic cells (THP-1), YAP-silencing only reduces the expression level of M2 markers (70); In hepatocytes, YAP-activating only promotes the polarization of TAMs into M2 phenotype (67); In pancreatic ductal adenocarcinoma (PDAC), YAP-deleting only promotes the polarization of TAMs into M1 phenotype (71); In colon cancer cells, down-regulation of YAP expression is not only inhibiting tumor development but also reducing the expression of IL-4 and IL-13 (70), which are vital inducers of M2 polarization, thereby inhibiting the polarization of TAMs into M2 phenotype.