The change in the proportion of annexin V-positive apoptotic cells under normoxic and hypoxic conditions after treatment with chemotherapy drugs.

<p>The proportion of annexin V-positive apoptotic cells(lower right quadrant) was evaluated by flow cytometry using annexin V allophycocyanin (APC) and propidium iodide (PI) staining of LoVo MCS after treatment with (B) ADR (25 µg/ml), (C) VCR (25 µg/ml), (D) 5-FU (200 µg/ml) and (E) CPT-11 (200 µg/ml). Untreated cells were used as negative control. Data of each statistical graph of Annexin V-APC/PI staining is expressed in % of cells in the lower right quadrant and represent the mean ± SD of three independent experiments. The bar charts at the bottom of the flow cytometry scatterplots represent the % of cells undergoing apoptosis in the lower right quadrant (**<i>p</i><0.01, N: normoxia, H: hypoxia).