Testican 3 expression in adult T-cell leukemia.

Adult T-cell leukemia (ATL) is an aggressive disease characterized by visceral invasion, and ATL regulates matrix metalloproteinase (MMP) activities of the endothelial cells. The controlling system of MMP activities in ATL is regulated by various factors such as Emmprin and tissue inhibitor of MMP. In this study, we demonstrated that Testican 3 expression in ATL decreased the activity of MMP. Furthermore, we showed that the expression of Testican 3 was regulated by activating transcriptional factor 3 in human T-lymphotropic virus type I-related cell lines. Thus, Testican 3 is a novel regulator to reduce the activity of MMP in ATL.