title: Enhancement of antineoplastic effect and attenuation of sister chromatid exchanges by prostaglandin E2 in Ehrlich ascites tumour cells treated with cyclophosphamide in vivo.
abstract: Reduced sister chromatid exchanges (SCE) frequency in response to cyclophosphamide (CP) was observed when Ehrlich ascites tumour (EAT) cells were exposed in vivo to 2 micrograms/g body weight of prostaglandin E2 (PGE2). 1 h before i.p. injection of 5-bromodeoxyuridine (BrdUrd) adsorbed to activated charcoal, EAT-bearing mice treated i.p. with CP appeared to have increased SCE rates and cell division delays. PGE2 had no effect on survival and in inhibiting tumour growth. CP had only a slight non-significant effect on survival and in inhibiting tumour growth. In mice treated with the combined CP (5 micrograms/g bd wt) plus PGE2 (2 micrograms/g bd wt) a significant enhancement (P < 0.01) of survival time was accompanied by inhibition of tumour growth (P < 0.01) in comparison with the untreated controls. These data imply that SCEs might result from errors in a repair process which might involve a PGE2 sensitive step.
authors.affiliation: Department of General Biology and Genetics, Faculty of Medicine, Aristotelian University, Thessaloniki, Greece.
authors.forename: D
authors.initials: D
authors.lastname: Mourelatos
authors.forename: Z
authors.initials: Z
authors.lastname: Kritsi
authors.forename: E
authors.initials: E
authors.lastname: Mioglou
authors.forename: J
authors.initials: J
authors.lastname: Dozi-Vassiliades
mesh_terms: D000818:Animals; D001973:Bromodeoxyuridine; D002286:Carcinoma, Ehrlich Tumor / Q000188:drug therapy* / Q000235:genetics; D003520:Cyclophosphamide / Q000494:pharmacology*; D015232:Dinoprostone / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D012854:Sister Chromatid Exchange / Q000187:drug effects*; D014407:Tumor Cells, Cultured
chemical_list: D003520:Cyclophosphamide; D001973:Bromodeoxyuridine; D015232:Dinoprostone