ANXA5 and acute lymphoblastic leukemia: For B-ALL cell lines, we observed an increase in the proportion of sensitive RS(4, 11) cells in early apoptosis (Annexin V+/PI- cells, ~15%) and late apoptosis (Annexin V+/PI+ cells, ~32%) 24 h after exposure to ASNase and this increase was detectable even at low doses (e.g. 5 × 10−5/ml).