Ubenimex

Ubenimex (Bestatin) is an inhibitor of aminopeptidase B, leukotriene A4 hydrolase, aminopeptidase N (Ki = 0.001 - 90 mM). Ubenimex inhibits enkephalin metabolism and leukotriene A4 hydrolase. Bestatin also inhibits tumor cell proliferation. Bestatin induced cell growth inhibition and phenotypic changes of HL-60 and HL-60R cell lines. In vitro, the upregulation of CD13/aminopeptidase N was found after 1 hr, however, the downregulation was observed after 3 hrs incubation with Ubenimex (Bestatin). On the other hand, the downregulation of CD15 and CD33 was observed after both one and 3 hrs incubation. Ubenimex may also be an effective anti-leukemic agent in vivo.