Mechanisms of Anthracycline-Enhanced Reactive Oxygen Metabolism in Tumor Cells

Table 10

Effect of oxygen radical scavengers on doxorubicin-enhanced formaldehyde production by detergent-treated Ehrlich tumor cells. Hydroxyl radical production by Ehrlich carcinoma cells was determined exactly as described in Table 9; data have been expressed as the of formaldehyde production for the 2 hr reaction interval in each experimental group, and the total number of experiments () has been given in parentheses.

Experimental conditions	Formaldehyde production (nmol/10^7 cells)
Doxorubicin (250 μM)	(6)^a
Plus SOD (20 μg/ml)	(6)^b
Plus heat-denatured SOD (20 μg/ml)^c	(3)
Plus catalase (3000 units/ml)	(3)^d
Plus heat-denatured catalase (3000 units/ml)	(3)
Plus sodium benzoate (100 mM)	(3)^b
Plus mannitol
100 mM	(3)^b
200 mM	(3)^d
Plus diethylurea (100 mM)	(3)^b
Plus dimethylthiourea (100 mM)	(3)^d
Plus urea (100 mM)	(3)

^a; ^bsignificantly different from samples treated with doxorubicin alone (); ^cSOD and catalase were autoclaved for 60 min; ^dsignificantly different from samples treated with doxorubicin alone ().