Enhancement of cytogenetic damage and of antineoplastic effect in lymphoid L1210 leukemia cells treated with prostaglandin E2 and cyclophosphamide in vivo.

An enhanced frequency of sister-chromatid exchanges (SCEs) and increased cell division delays induced by cyclophosphamide (CP) were observed when lymphoid L1210 leukemia cells were post-treated in vivo with prostaglandin E2 (PGE2). CP gave a slight, non-significant increase in survival while PGE2 gave a slight, non-significant decrease in survival. However, PGE2 in combination with CP was found to have a non-significant potentiating effect on survival in comparison with mice treated with CP alone. In mice treated with the combined CP (5 micrograms/g b.w.) plus PGE2 (2 micrograms/g b.w.) treatment, a significant (P < 0.01) enhancement of survival time in comparison with the untreated controls was observed.