Novel Phenazine 5,10-Dioxides Release ^•OH in Simulated Hypoxia and Induce Reduction of Tumour Volume In Vivo

Table 1

PDO cytotoxic effects in simulated hypoxia and normoxia on different conditions and cellular systems.

Comp.	Dose (μM)	SF^a,b,c in simulated hypoxia		SF^a,b,c in normoxia
		−vitC^d	+vitC	−vitC	+vitC
PDO2	5	3 ± 1	0 ± 0	87 ± 5	83 ± 4
PDO3	20	11 ± 2	8 ± 2	61 ± 3	74 ± 2
PDO4	5	4 ± 1	0 ± 0	67 ± 3	80 ± 5
Comp.	Dose (μM)	SFahypoxia^,b		SFaoxia^,b
	20	0 ± 0		5 ± 1	MCF-7
PDO2	5	0 ± 0		34 ± 3
	20	0 ± 0		26 ± 3	TK-10
	20	0 ± 0		18 ± 2	HT-29

^aSF: survival fractions (%).^bValues are means of two different experiments. The assays were done by duplicate and using at least three repetitions, and standard errors were not greater than 2 % for most assays. ^cUsing V79 cells. ^dvitC: vitamin C (pretreatment during 25 min with equimolecular amount of vitamin).