Anti-tumor-promoting effects of glycoglycerolipid analogues on two-stage mouse skin carcinogenesis

Four glycoglycerolipid analogues, 1-O-hexanoyl-2-O-β-D-glucopyranosyl-sn-glycerol (1), 1-O-hexanoyl-2-O-β-D-galactopyranosyl-sn-glycerol (2), 2-O-(6-O-hexanoyl-β-D-galactopyranosyl)-sn-glycerol (3) and 2-O-(6-O-hexanoyl-α-D-galactopyranosyl)-sn-glycerol (4), potent in vitro inhibitors of 12-O-tetradecanoylphorbol-13-acetate (TPA) induced Epstein-Barr virus early antigen (EBV-EA) activation, were submitted to an in vivo two-stage mouse skin carcinogenesis test, using dimethylbenz[a]anthracene (DMBA) and TPA. The study was extended to two deacylated galactosylglycerol structures, 1-O-β-D-galactopyranosyl-sn-glycerol (5) and 3-O-β-D-galactopyranosyl-sn-glycerol (6). All the tested compounds exhibited remarkable anti-tumor-promoting effects on mouse skin tumor promotion, the 1-hexanoate 2 being the most active among the glycoglycerolipids until now studied. (C) 2000 Elsevier Science Ireland Ltd.