BCL2 and B-cell chronic lymphocytic leukemia: Unlike the increase in Bcl-2 expression observed in CLL cells from treatment naïve patients ex vivo (Fig. 4b, center), we here observed a very slight decrease in Bcl-2 expression at week 8 compared to baseline, while there was a further reduction at progression (week 16), followed by an increase again off study (week 36) (Fig. 5k, right).