CASP3 and B-cell chronic lymphocytic leukemia: Cases reported in Table 2 have been selected based on several criteria: (1) to show that the effects of quercetin in enhancing DR-induced cell death in terms of decrease in cell viability, caspase-3 activation, and Annexin V positivity are more than additive (arrows), supporting the apoptogenic sensitising capacity of quercetin (CLL-55, 56, 44, and 11); (2) to show that a limited percentage of samples (about 10%) isolated from B-CLL patients neither respond to quercetin, nor to the combined treatment (CLL-42), even if a transient increase in caspase-3 was detected.