Data for B-CLL samples and patients are summarized (N = number tested). For 13q14LOH, ex vivo chemosensitivity, spontaneous apoptosis, and Rai stage, the frequency of patients in each response category is indicated, as well as the percentage of patients who were positive for 13q14LOH, exhibited sensitivity to drugs in vitro, had high rates of spontaneous apoptosis, or who had low Rai stage.

Densitometry scores were dichotomized into high- and low-expression groups based on direct comparisons with R11846 cells (“high” ≥1.0 vs “low” <1.0. For Bcl-2, two different cutoffs were employed.

13q14 LOH based on nine microsatellite markers.33 

In vitro resistance to fludarabine defined as IC₅₀>10⁻⁵ mol/L.

High spontaneous apoptosis defined as 20% or more.