Bestatin (Ubenimex)

Bestatin inhibits proliferation of all the human leukemic cell lines except KG1. Bestatin induces DNA fragmentation quantitatively and DNA ladder and enhances caspase-3 activity in U937 cells. Bestatin dose-dependently induces DNA fragmentation in human leukemic cell lines. ^[1] Bestatin dose-dependently inhibits the invasion of SN12M cells into reconstituted basement membrane (Matrigel). Bestatin inhibits the degradation of type IV collagen by tumor cells, but not by tumor-conditioned medium (TCM), in a concentration-dependent manner. Bestatin inhibits hydrolysing activities towards substrates of aminopeptidases in SN12M cells. ^[2] Bestatin inhibits the tube-like formation of human umbilical vein endothelial cells (HUVECs) in vitro. ^[3] Bestatin exerts a direct stimulating effect on lymphocytes (and monocytes) via its fixation on cell surface leucine-aminopeptidase, and an indirect effect on monocytes (and lymphocytes) via aminopeptidase B inhibition of tuftsin catabolism. ^[4]

Bestatin significantly inhibits the melanoma cell-induced angiogenesis in a mouse dorsal air sac assay. Bestatin reduces the number of vessels oriented towards the established primary tumor mass on the dorsal side of mice implantated of B16-BL6 melanoma cells. ^[3] Bestatin statistically significantly inhibits leukotriene B4 biosynthesis in the esophageal tissues of EGDA rats and reduces the incidence of EAC in the EGDA rats from 57.7% (15 of 26 rats) to 26.1% (6 of 23 rats). ^[5]