Table 1.

Impact of acute and chronic hypoxia on PC-3 cell proliferation and cell death

	Normoxia	Hypoxia
		2 h†	6 h†	24 h††	48 h§
Cell proliferation (%)||	100.0 ± 0.0	99.8 ± 1.7	98.5 ± 3.1	89.1 ± 3.3**	75.5 ± 3.7***
Cell death (%)¶	2.5 ± 1.3	2.7 ± 1.5	2.7 ± 2.1	4.8 ± 2.1	17.3 ± 5.1***

Note:

^†Cells were cultured under hypoxic conditions (1% O₂) for 2 or 6 h, and re-cultured under 20% O₂ for 22 or 18 h, respectively. For cell proliferation, † and †† were compared with 24 h normoxia, and § was compared with 48 h normoxia.

^||Relative cell number under 24 h or 48 h normoxia was defined as 100%.

^¶Cell death was expressed as the average number of trypan blue-positive cells after culturing under 20% O₂ for 24 h and 48 h (there is no difference on trypan blue-positive cell number with these two durations). Data are presented as mean ± SD (n=3).

^**p < 0.01;

^***p < 0.001 vs. normoxia (t-test).