TABLE 2.

Effect of transient overexpression of Trx or dnTrx and down-regulation of Trx on RNR activity in hypoxia

MCF-7 cells were transfected with AdenoX constructs containing Trx or dnTrx cDNA as mentioned under “Experimental Procedures,” and after 48 h Trx enzyme-linked immunosorbent assay was performed on some samples. The transfected cells were exposed to normoxia or hypoxia for 24 h, and RNR activity assay was performed as described under “Experimental Procedures.” In some experiments nontargeting siRNA or Trx RNA was transfected into MCF-7 cells, and RNR activity was determined as described under “Experimental Procedures.” The experiment was performed in triplicate.

	Trx	CDP reduction		p value
		21% O2	0.2% O2
	pg/mg protein	pmol/mg/h
AdenoX LacZ	742 ± 44	287 ± 52	251 ± 91	0.29
AdenoX Trx	1643 ± 85	327 ± 43	290 ± 76	0.25
AdenoX dnTrx	2375 ± 96	242 ± 84	109 ± 33	0.03
MCF (NT siRNA)		479 ± 58	521 ± 27	0.84
MCF Trx siRNA		496 ± 72	322 ± 65	0.01