The effect of the non-ionic surfactant brij 30 on the cytotoxicity of adriamycin in monolayer, spheroid and clonogenic culture systems

The effects of a non-ionic polyoxyethylated lauryl ether surfactant (Brij 30) on monolayer uptake and spheroid penetration of adriamycin have been studied. Co-incubation of adriamycin with Brij 30 increases intracellular adriamycin levels by 2-3-fold. Although, in the concentrations used, Brij 30 alone is not cytotoxic, adriamycin and Brij 30 mixtures are significantly more cytotoxic (monlayer id₉₀ = 0.6 μg/ml; disaggregated spheroid id₃₀ = 1.9 μg/ml) and induce significantly longer spheroid growth delay than adriamycin alone (monolayer id₉₀ = 2.1 μg/ml; disaggregated spheroid id₅₀ = 3.3 μg/ml). Adriamycin is equally cytotoxic to mouse normal granulocytes and chronic myeloid leukaemic (M1 cell line) cells in agar clonogenic cultures. The addition of Brij 30 appears to enhance preferentially the activity of adriamycin against these tumour cells relative to the normal granulocytes.