Figure 3

Hypoxia promotes proliferation of T-ALL cells by reducing the G0/G1 phase of the cell cycle. (A) Jurkat and Sup-T1 cells were cultured in hypoxia for up to 72 h, causing increased cell growth compared with normoxia. *, P < 0.01. Results are an average of three independent experiments. (B) After exposure to normoxia (a, c) or hypoxia (b, d) for 48 h, T-ALL cells were stained with PI and analyzed for their DNA content using FACS Calibur. The percentage of cells in G1/G0, S and G2/M in each group is shown in (C). *, P < 0.01. Data plotted are mean ± SD of three separate experiments. (D) Representative Western blot of cell cycle regulators Cyclin D1, CDK2 and p21 in cells cultured under hypoxic conditions for 48 h. Results shown are representative of at least three independent experiments.