In order to study whether TGF‐β2 induces mesenchymal transition of the primary TECs derived from human tumor xenograft model, we isolated endothelial cells from the tumors arisen from the highly metastatic A375SM human melanoma cells subcutaneously transplanted to immune‐deficient nude mice, followed by establishment of TECs (Maishi et al., 2016). Here, TGFB2 is linked to melanoma.